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Sample records for grazing pastures fertilized

  1. Forage mineral concentration, animal performance, and mineral status of heifers grazing cereal pastures fertilized with sulfur.

    PubMed

    Hardt, P F; Ocumpaugh, W R; Greene, L W

    1991-06-01

    Thirty yearling Santa Gertrudis-sired heifers (average initial weight 238 kg) were continuously grazed (five heifers/pasture) on six 2-ha oat-wheat small grain pastures for 112 d to determine the effect of fertilization of pastures with urea (U) vs ammonium sulfate (AS) on mineral status and performance of heifers. Pastures were fertilized with either U, at 200 kg/ha, or AS, at 438 kg/ha, to provide 92 kg of N/ha in November 1987 and March 1988. Ammonium sulfate provided 107 kg of S/ha. Forage samples were collected during each month. Heifers were initially weighed following an overnight fast and at the end of four consecutive 28-d intervals (Periods 1 to 4). Serum and ruminal fluid were collected on d 56 and 112. Pastures fertilized with AS had a greater (P less than .10) in vitro dry matter disappearance during Periods 2 and 3. Ammonium sulfate-fertilized pastures had greater than (P less than .05) S concentrations from January 29 through termination of the trial. There were no differences in ADG (P less than .28) or gain/ha (GPH; P less than .43) over 112 d; however, heifer ADG was greater (P less than .08) in Period 3 and tended to be greater (P less than .16) in Period 2 for those animals grazing U-fertilized pastures. Pastures receiving AS produced less (P less than .04) GPH during Period 2. Ammonium sulfate fertilization in this trial had no effect on forage K, Ca, P, Mg, Cu, or Mo mineral concentrations or on serum mineral and ruminal VFA concentrations, but it did result in an increase in IVDMD and a trend for decreased ADG apparently associated with a decrease in forage intake. PMID:1653192

  2. Alkyl Phenols and Diethylhexyl Phthalate in Tissues of Sheep Grazing Pastures Fertilized with Sewage Sludge or Inorganic Fertilizer

    PubMed Central

    Rhind, Stewart M.; Kyle, Carol E.; Telfer, Gillian; Duff, Elizabeth I.; Smith, Alistair

    2005-01-01

    We studied selected tissues from ewes and their lambs that were grazing pastures fertilized with either sewage sludge (treated) or inorganic fertilizer (control) and determined concentrations of alkylphenols and phthalates in these tissues. Mean tissue concentrations of alkylphenols were relatively low (< 10–400 μg/kg) in all animals and tissues. Phthalates were detected in tissues of both control and treated animals at relatively high concentrations (> 20,000 μg/kg in many tissue samples). The use of sludge as a fertilizer was not associated with consistently increased concentrations of either alkylphenols or phthalates in the tissues of animals grazing treated pastures relative to levels in control animal tissues. Concentrations of the two classes of chemicals differed but were of a similar order of magnitude in liver and muscle as well as in fat. Concentrations of each class of compound were broadly similar in tissues derived from ewes and lambs. Although there were significant differences (p < 0.01 or p < 0.001) between years (cohorts) in mean tissue concentrations of both nonylphenol (NP) and phthalate in each of the tissues from both ewes and lambs, the differences were not attributable to either the age (6 months or 5 years) of the animal or the duration of exposure to treatments. Octylphenol concentrations were generally undetectable. There was no consistent cumulative outcome of prolonged exposure on the tissue concentrations of either class of pollutant in any ewe tissue. Mean tissue concentrations of phthalate were higher (p < 0.001) in the liver and kidney fat of male compared with female lambs. We suggest that the addition of sewage sludge to pasture is unlikely to cause large increases in tissue concentrations of NP and phthalates in sheep and other animals with broadly similar diets and digestive systems (i.e., domestic ruminants) grazing such pasture. PMID:15811823

  3. Effects of nitrogen fertilization on soil nutrient concentration and phosphatase activity and forage nutrient uptake from a grazed pasture system.

    PubMed

    Dillard, Sandra Leanne; Wood, Charles Wesley; Wood, Brenda Hall; Feng, Yucheng; Owsley, Walter Frank; Muntifering, Russell Brian

    2015-05-01

    Over a 3-year period, the effect of differing N-application regimes on soil extractable-P concentration, soil phosphatase activity, and forage P uptake in a P-enriched grazed-pasture system was investigated. In the fall of each year, six 0.28-ha plots were overseeded with triticale ( × Triticosecale rimpaui Wittm.) and crimson clover (Trifolium incarnatum) into a tall fescue (Lolium arundinacea)/bermudagrass (Cynodon dactylon) sod and assigned to 1 of 3 N-fertilizer treatments (n = 2): 100% of N recommendation in a split application (100N), 50% in a single application (50N), and 0% of N recommendation (0N) for triticale. Cattle commenced grazing the following spring and grazed until May. In the summer, plots were overseeded with cowpea (Vigna unguiculata), fertilized at the same rates by reference to N recommendations for bermudagrass, and grazed by cattle until September. There were no effects of N fertilization on soil phosphatase activity, electrical conductivity, or concentrations of water-soluble P. Concentrations of extractable P decreased in plots receiving 50N, but increasing N fertilization to 100N resulted in no further reduction in extractable P. Forage biomass, foliar P concentrations, and forage P mass were not affected by N fertilization rates at the plant-community level, but responses were observed within individual forage species. Results are interpreted to mean that N fertilization at 50% of the agronomic recommendation for the grass component can increase forage P mass of specific forages and decrease soil extractable P, thus providing opportunity for decreasing P losses from grazed pasture.

  4. Effects of nitrogen fertilization on soil nutrient concentration and phosphatase activity and forage nutrient uptake from a grazed pasture system.

    PubMed

    Dillard, Sandra Leanne; Wood, Charles Wesley; Wood, Brenda Hall; Feng, Yucheng; Owsley, Walter Frank; Muntifering, Russell Brian

    2015-05-01

    Over a 3-year period, the effect of differing N-application regimes on soil extractable-P concentration, soil phosphatase activity, and forage P uptake in a P-enriched grazed-pasture system was investigated. In the fall of each year, six 0.28-ha plots were overseeded with triticale ( × Triticosecale rimpaui Wittm.) and crimson clover (Trifolium incarnatum) into a tall fescue (Lolium arundinacea)/bermudagrass (Cynodon dactylon) sod and assigned to 1 of 3 N-fertilizer treatments (n = 2): 100% of N recommendation in a split application (100N), 50% in a single application (50N), and 0% of N recommendation (0N) for triticale. Cattle commenced grazing the following spring and grazed until May. In the summer, plots were overseeded with cowpea (Vigna unguiculata), fertilized at the same rates by reference to N recommendations for bermudagrass, and grazed by cattle until September. There were no effects of N fertilization on soil phosphatase activity, electrical conductivity, or concentrations of water-soluble P. Concentrations of extractable P decreased in plots receiving 50N, but increasing N fertilization to 100N resulted in no further reduction in extractable P. Forage biomass, foliar P concentrations, and forage P mass were not affected by N fertilization rates at the plant-community level, but responses were observed within individual forage species. Results are interpreted to mean that N fertilization at 50% of the agronomic recommendation for the grass component can increase forage P mass of specific forages and decrease soil extractable P, thus providing opportunity for decreasing P losses from grazed pasture. PMID:25728918

  5. Chronic copper poisoning in sheep grazing pastures fertilized with swine manure

    SciTech Connect

    Kerr, L.A.; McGavin, H.D. )

    1991-01-01

    Several pregnant ewes developed an acute hemolytic crisis and died. Liver and kidney copper concentrations were high, confirming chronic copper poisoning as the cause of death. Feed and water samples that the affected ewes had been consuming did not contain excess copper. Because swine manure slurry had been applied to the pasture where the sheep had grazed, a copper analysis was conducted on soil and forage samples from this field. High copper concentrations were detected in the soil and forage samples from the slurry pasture. Most sheep producers are aware of the catastrophic consequences that result when feeds containing copper and insufficient amounts of molybdenum are fed to sheep. However, producers and veterinarians often are unaware of some of the subtle sources of copper. Most of the copper that is added to swine and poultry feeds as growth promotants passes through the gastrointestinal tract unabsorbed and remains in the waste material. Pastures that have copper-containing waste material, but no molybdenum applied, can produce the same fatal results as giving sheep feed supplemented with copper but containing no molybdenum.

  6. Effects of stocking and nitrogen fertilization rates on steers grazing dallisgrass-dominated pasture.

    PubMed

    Gunter, S A; Beck, P A; Hutchison, S; Phillips, J M

    2005-09-01

    To compare the performance of steer calves managed under different stocking rates (SR; 3.7, 6.2, 8.6, and 11.1 steers/ha for 140 d; chi(I1)) and N fertilization rates (112, 224, and 336 kg of N/ha; chi(I2)) in May 1996, 1997, and 1998, 72 steer calves (BW = 231 +/- 2.5 kg) were assigned randomly to one of 12 0.81-ha dallisgrass (51%)/common bermudagrass (32%) pastures. One-third of the fertilizer was applied in the form of ammonium nitrate in May, June, and August to achieve the prescribed totals. Treatments were separated using a polynomial regression equation: gammai = beta0 + beta1chi(I1) + beta2chi(I2) + beta(11)chi2(I1) + beta(12)chi2(I2) + beta(12)chi(i1)chi(i2) + epsilonI, with years as replicates. Within the range of the data, ADG and BW gain per steer were greatest at a stocking rate of 3.7 steers/ha and 336 kg/ha of N. Body weight gain per hectare peaked at 701 kg when cattle were stocked at 8.9 steers/ha and the pasture was fertilized with 336 kg/ha of N. The least cost of production was at a stocking rate of 3.7 steers/ha, with 112 kg/ha of fertilizer N applied, and the greatest cost of production was at a stocking rate of 11.1 steers/ha with 336 kg/ha of fertilizer N applied. Fertilization at 336 kg/ha of N produced the most profitable stocking rate at 7.3 steers/ha and returned 355.64 dollars. The optimal stocking rate for net return was 79, 81, and 82% of that for maximum BW gain per hectare for 112, 224, and 336 kg/ha of N, respectively. Under the assumptions made in the financial analysis, these data show that the economically optimal carrying capacity of similar pastures can be increased with N fertilizer up to at least 336 kg/ha annually.

  7. Pasture quality variation throughout the grazing season

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It is important for dairy producers and their nutritionists to have an idea of the nutritional quality of the pasture they are providing to their cows. This article uses data gathered from several on-going pasture research projects to demonstrate how pasture quality varies during the grazing season,...

  8. Nitrogen Isotopes as an Indicator of Long-Term N Cycling in a Grazed Temperate Pasture Receiving Different Rates of Superphosphate Fertilizer and Irrigation for ~50 Years

    NASA Astrophysics Data System (ADS)

    Mudge, P. L.; Schipper, L. A.; Ghani, A.; Baisden, W. T.; Dodd, M.

    2010-12-01

    Pastoral agriculture is the dominant land use in New Zealand and intensification (as a result of fertilizer inputs and in some areas irrigation) has led to increased nitrogen (N) losses to the wider environment. An indicator that could identify soils which are vulnerable to N loss would be useful for the development of management practices and regulations aimed at reducing unwanted N losses. The natural abundance of 15N relative to 14N (δ15N) in soils is one potential indicator. Most N cycle processes associated with N losses (e.g. nitrification, denitrification, and volatilisation) discriminate against 15N and therefore soil δ15N could provide an indication of cumulative N losses. In this study we measured δ15N in archived soils from two long-term field trials receiving different rates of superphosphate fertilizer and irrigation. Both trials were in mid-Canterbury, New Zealand and were grazed by sheep. The fertilizer trial began in 1952, and treatments used were the control (nilP), 376 kg superphosphate ha-1 y-1 (376PA) and a treatment where 376 kg superphosphate ha-1 y-1 was applied between 1952 and 1957, no fertilizer from 1958 to 1979 and then 250 kg superphosphate ha-1 y-1 from 1980 to 2009 (376-0-250PA). The irrigation trial was initiated in 1949 and ceased in 2002. The dryland treatment and treatments irrigated when soil moisture was 10% and 20% were used in this study. From 1958, soil samples (0-75 mm depth) were taken annually from each trial, air dried and archived. Soil samples at four year intervals were analysed for this study. Pasture production varied considerably between treatments, with higher rates of fertilizer and irrigation promoting greater pasture growth and therefore higher grazing intensities. Initially δ15N was about the same (3.3‰) in all treatments of both trials. δ15N in the 376PA treatment of the fertilizer trial increased gradually with time and by 2009 was 4.5‰. In the 376-0-250PA treatment, δ15N stayed constant until about

  9. Carbon budgets for an irrigated intensively grazed dairy pasture and an unirrigated winter-grazed pasture

    NASA Astrophysics Data System (ADS)

    Hunt, John E.; Laubach, Johannes; Barthel, Matti; Fraser, Anitra; Phillips, Rebecca L.

    2016-05-01

    Intensification of pastoral agriculture is occurring rapidly across New Zealand, including increasing use of irrigation and fertiliser application in some regions. While this enables greater gross primary production (GPP) and livestock grazing intensity, the consequences for the net ecosystem carbon budget (NECB) of the pastures are poorly known. Here, we determined the NECB over one year for an irrigated, fertilised and rotationally grazed dairy pasture and a neighbouring unirrigated, unfertilised, winter-grazed pasture. Primary terms in the NECB calculation were: net ecosystem production (NEP), biomass carbon removed by grazing cows and carbon (C) input from their excreta. Annual NEP was measured using the eddy-covariance method. Carbon removal was estimated with plate-meter measurements calibrated against biomass collections, pre- and post-grazing. Excreta deposition was calculated from animal feed intake. The intensively managed pasture gained C (NECB = 103 ± 42 g C m-2 yr-1) but would have been subject to a non-significant C loss if cattle excreta had not been returned to the pasture. The unirrigated pasture was C-neutral (NECB = -13 ± 23 g C m-2 yr-1). While annual GPP of the former was almost twice that of the latter (2679 vs. 1372 g C m-2 yr-1), ecosystem respiration differed by only 68 % between the two pastures (2271 vs. 1352 g C m-2 yr-1). The ratio of GPP to the total annual water input of the irrigated pasture was 37 % greater than that of the unirrigated pasture, i.e. the former used the water input more efficiently than the latter to produce biomass. The NECB results agree qualitatively with those from many other eddy-covariance studies of grazed grasslands, but they seem to be at odds with long-term carbon-stock studies of other New Zealand pastures.

  10. Pasture growth and decomposition under continuous and rotational grazing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Past research has shown that grazing management can affect both pasture growth and litter decomposition. The objective of this study was to compare forage appearance (growth) and forage disappearance (decomposition) on both continuous and rotational grazed beef cattle pasture in Ohio. Data was colle...

  11. Improvement of natural pastures using liquid organic fertilizers

    NASA Astrophysics Data System (ADS)

    Ghambashidze, Giorgi; Gabedava, Giorgi; Abuladze, Paata

    2016-04-01

    Nowadays natural pastures remains the main source to supply livestock with fresh feed material in Georgia. Due to that common pasturelands are under continues grazing pressure and normally no measures are taken in order to improve pasture productivity and to protect soil from erosion. Unregulated stocking rate leads to overutilization of natural pastures causing reduction in productivity and soil fertility. It is especially evident in arid regions, where bare soil after removal of vegetation dries out and is subject to wind erosion. In many areas even with regulated stocking rate plant available soil nutrient pool is already diminished and vegetation cannot be recovered easily after grazing. Therefore it is essential to improve soil fertility, which provide adequate amount of nutrients to plants to regenerate. Ongoing study aims to compare effect of different types of organic fertilizers on natural pastures in combination with pasture rotation scheme in order to maintain soil fertility and prepare the basis for its gradual improvement. Initial results shows positive impact of liquid organic fertilizers which increased aboveground biomass production by 200-300 kg per hectare.

  12. Pasture-scale measurement of methane emissions of grazing cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Quantifying methane emission of cattle grazing on southern Great Plains pastures using micrometeorology presents several challenges. Cattle are elevated, mobile point sources of methane, so that knowing their location in relation to atmospheric methane concentration measurements becomes critical. St...

  13. Conversion of Grazed Pastures to Energy Cane as a Biofuel Feedstock Alters Soil GHG Fluxes

    NASA Astrophysics Data System (ADS)

    Gomez-Casanovas, N.; DeLucia, N.; Bernacchi, C.; DeLucia, E. H.

    2013-12-01

    Changes in land use profoundly affect climate through variations in soil Greenhouse Gas (GHG) exchange. The need for alternative energies is accelerating land use change as marginal land or managed ecosystems are being converted to highly productive second-generation bioenergy crops such as energy cane (Saccharum spp. L). Although the deployment of energy cane is a promising strategy to meet global bioenergy industry demands, few studies have investigated soil GHG fluxes in these crops and sub-tropical low-intensity grazing pasture (bahiagrass, Paspalum notatum L., as forage for cattle, Bos taurus L.) with which they are competing for land. Here, we showed that soil N2O fluxes in bioenergy crops were higher (>250%) than those observed in pastures following fertilization when soil moisture and temperature were high. In the absence of recent fertilization, the N2O source strength in energy cane and pasture sites was similar. Under drier and cooler soil conditions, both pastures and bioenergy crops were weak sources of N2O even when energy cane plots were recently fertilized. Soils on grazed pastures were sources of CH4 during the wet season but became sinks under drier, colder conditions. Energy cane plantations were weak sources of CH4 over a complete wet-dry seasonal cycle. The heterotrophic component of soil respiration was larger (139-155%) in pastures than in energy cane crops, suggesting lower decomposition of SOC in bioenergy crops. In terms of global warming potential, grazed pastures were stronger (120-150%) soil GHG emitters than energy cane crops over a complete wet-dry seasonal cycle. Moreover, pastures became a substantial source of GHG emitters when including estimates of CH4 flux from cattle. Our results suggest that the conversion of pasture to energy cane will be beneficial in relation to GHGs emitted from soils and cattle. Improved understanding of land use impact on soil GHG dynamics will provide valuable information for decision makers debating

  14. Management intensive grazing and continuous grazing of hill pasture by beef cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Management Intensive Grazing (MIG) is an increasingly used practice that can offer producers many benefits including higher profit. The main objective of this study was to compare MIG and Continuous Grazing (CG)practices on pastures in Appalachian Ohio. The study was conducted at the North Appalac...

  15. Polioencephalomalacia in adult sheep grazing pastures with prostrate pigweed

    PubMed Central

    2005-01-01

    Abstract Polioencephalomalacia was diagnosed in 2 animals from different farms. In apparently healthy animals from same farms, fecal thiaminase and a significant reduction in erythrocyte transketolase activity was observed. The presence of thiaminase in Amaranthus blitoides could have contributed to the development of polioencephalomalacia in sheep grazing on natural pastures. PMID:15759830

  16. EFFECTS OF FERTILIZER TYPE (CHICKEN LITTER VS. INORGANIC FERTILIZER) AND CATTLE GRAZING ON THE SOIL MICROBIAL COMMUNITY

    EPA Science Inventory

    Pasture plots included unharvested, hayed, light and heavy cattle grazing pressure, fertilized with either inorganic N-P-K or broiler litter. Total phospholipid fatty acids (PLFAs) followed a seasonal trend and were higher in grazed plots than hayed & unharvested plots. Fungi a...

  17. Soil fertility management on natural pastures in Eastern Georgia

    NASA Astrophysics Data System (ADS)

    Ghambashidze, Giorgi; Jolokhava, Tamar; Kenchiashvili, Naira; Tarkhnishvili, Maia

    2015-04-01

    The development of livestock production in Georgia is mainly based on productivity of natural common pasturelands as it is the cheapest way to keep animals. Therefore it is crucial to manage those pastures in order to supply domestic animals with adequate amount of green grass during whole grazing season. The problems associated with poor grassland management is especially evident under limited rainfall conditions. Usually farmers do not consider suitability of existing stocking rates with pasture productivity leading to overutilization of pastureland causing reduction of palatable plant species and total grass cover stimulating soil erosion processes, which deflates soil nutrients and soil organic matter. Intensification of negative processes may result in loss of soil fertility and poor grass regrowth capacities. Current study aims to evaluate existing grazing system on a selected plots from common pasturelands in Eastern Georgia and to develop a proper soil fertility management plan accepted in organic agriculture taking into account local soil-climatic conditions, pasture vegetation stand and its richness with palatable plant species.

  18. Grazing Stategy To Decrease Dietary Crude Protien Wastage In Stocker Calves Grazing Winter Wheat Pasture.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Annual cool-season grasses, primarily winter wheat, provide high quality forage for stocker calves during the fall, winter and spring grazing seasons for stocker enterprises in the southern Great Plains. The crude protein (CP) content of winter wheat pasture exceeds the stocker calf’s daily CP requi...

  19. Herbage intake, methane emissions and animal performance of steers grazing dwarf elephant grass v. dwarf elephant grass and peanut pastures.

    PubMed

    Andrade, E A; Almeida, E X; Raupp, G T; Miguel, M F; de Liz, D M; Carvalho, P C F; Bayer, C; Ribeiro-Filho, H M N

    2016-10-01

    Management strategies for increasing ruminant legume consumption and mitigating methane emissions from tropical livestock production systems require further study. The aim of this work was to evaluate the herbage intake, animal performance and enteric methane emissions of cattle grazing dwarf elephant grass (DEG) (Pennisetum purpureum cv. BRS Kurumi) alone or DEG with peanut (Arachis pintoi cv. Amarillo). The experimental treatments were the following: DEG pastures receiving nitrogen fertilization (150 kg N/ha as ammonium nitrate) and DEG intercropped with peanut plus an adjacent area of peanut that was accessible to grazing animals for 5 h/day (from 0700 to 1200 h). The animals grazing legume pastures showed greater average daily gain and herbage intake, and shorter morning and total grazing times. Daily methane emissions were greater from the animals grazing legume pastures, whereas methane emissions per unit of herbage intake did not differ between treatments. Allowing animals access to an exclusive area of legumes in a tropical grass-pasture-based system can improve animal performance without increasing methane production per kg of dry matter intake.

  20. Herbage intake, methane emissions and animal performance of steers grazing dwarf elephant grass v. dwarf elephant grass and peanut pastures.

    PubMed

    Andrade, E A; Almeida, E X; Raupp, G T; Miguel, M F; de Liz, D M; Carvalho, P C F; Bayer, C; Ribeiro-Filho, H M N

    2016-10-01

    Management strategies for increasing ruminant legume consumption and mitigating methane emissions from tropical livestock production systems require further study. The aim of this work was to evaluate the herbage intake, animal performance and enteric methane emissions of cattle grazing dwarf elephant grass (DEG) (Pennisetum purpureum cv. BRS Kurumi) alone or DEG with peanut (Arachis pintoi cv. Amarillo). The experimental treatments were the following: DEG pastures receiving nitrogen fertilization (150 kg N/ha as ammonium nitrate) and DEG intercropped with peanut plus an adjacent area of peanut that was accessible to grazing animals for 5 h/day (from 0700 to 1200 h). The animals grazing legume pastures showed greater average daily gain and herbage intake, and shorter morning and total grazing times. Daily methane emissions were greater from the animals grazing legume pastures, whereas methane emissions per unit of herbage intake did not differ between treatments. Allowing animals access to an exclusive area of legumes in a tropical grass-pasture-based system can improve animal performance without increasing methane production per kg of dry matter intake. PMID:27101877

  1. Grazing alters the net C sink strength and the net global warming potential of a subtropical pasture

    NASA Astrophysics Data System (ADS)

    Gomez-Casanovas, N.; DeLucia, N.; DeLucia, E. H.; Boughton, E. H.; Keel, E.; Bernacchi, C.

    2014-12-01

    Grazing profoundly affects climate by altering the exchange of greenhouse gases (GHG; CO2 and CH4) between terrestrial ecosystems and the atmosphere. Little is known about how this disturbance affects the GHG exchange from subtropical pastures although they account for a substantial portion of global grazing lands. Here, we investigated how cattle grazing affect net ecosystem CO2 exchange (NEE) and CH4 emissions in subtropical semi-native pasture using the eddy covariance technique. Soil moisture was greater under grazed than ungrazed pastures but soil temperature was similar between treatments. By removing aboveground biomass, grazing reduced gross primary productivity (GPP, 16%). While ungrazed pastures had higher GPP than grazed pastures, they also had higher ecosystem respiration (Re, 20%) along with higher heterotrophic respiration. As a result, annual sums of NEE were similar in grazed and ungrazed pastures and both systems were net sinks for CO2 (-86 ± 5 gC m-2 yr-1 in grazed pasture, and -76 ± 6 gC m-2 yr-1 in ungrazed pasture). Including C removal by grazers in the C budget, grazing reduced the C sink strength (250%) and grazed pasture became a net source of C to the atmosphere. Increased soil wetness and CH4 production from enteric ruminant fermentation enhanced net ecosystem CH4 emissions (16%) in grazed than in ungrazed pastures. The net global warming potential (GWP) was higher (34%) in grazed than in ungrazed pastures, but both systems were net sources of GHGs when accounting for the radiative forcing of CH4. Our results suggest that grazing reduces the net C sink strength and increases the net GWP of subtropical pastures. Improved understanding of how grazing affects ecosystem GHG fluxes is essential to predicting the role of pastures on the global C cycle.

  2. High intensity, short duration rotational grazing on reclaimed cool season tall fescue/legume pastures: II. Forage production, soil and plant tissue comparisons between grazed and ungrazed pastures

    SciTech Connect

    Carlson, K.E.; Erickson, W.R.; Bonine, R.C.

    1995-09-01

    The Midway Mine is located 50 miles south of Kansas City, Kansas straddling the border of Kansas and Missouri. The Pittsburg & Midway Coal Mining Co. mined the area until 1989, when the mine was closed and reclaimed. Approximately 3,750 acres were topsoiled and revegetated with a cool season tall fescue/legume pasture. High intensity, short duration rotational grazing has become the preferred management practice on these pastures. This study evaluated soil and vegetation data collected on 1,250 acres of pasture which was grazed by about 550 cow/calf units. Ongoing monitoring programs are evaluating the effects of rotational grazing. Soil testing includes macro-nutrients, micro-nutrients and microbial activity. Plant tissue analyses monitor levels of principal macro-nutrients and micro-nutrients. Vegetation monitoring consists of measuring forage production. Results were contrasted between pregrazing and postgrazing, and grazed and ungrazed pasture. Agronomic data from the grazed versus ungrazed treatments documented the following results: (1) higher levels of plant tissue nitrate, phosphorus, potassium, calcium, magnesium, sodium and sulfur; (2) higher microbial activity; (3) similar levels of soil nitrate, phosphorus, potassium, calcium, magnesium, sodium and sulfur; and (4) increased biomass production.

  3. Meta-analysis of the effect of pregrazing pasture mass on pasture intake, milk production, and grazing behavior of dairy cows strip-grazing temperate grasslands.

    PubMed

    Pérez-Prieto, L A; Delagarde, R

    2012-09-01

    Grazing management is a key factor in pasture-based dairy systems, which can be improved given advanced knowledge of the effects of pregrazing pasture mass (PM) on the performance of dairy cows. The aim of this study was to quantify the effects of PM on the pasture intake, milk production, milk composition, and grazing behavior of strip- or rotational-grazing dairy cows, based on a meta-analysis of published research papers. A database was created that included experiments in which the effects of PM on pasture intake and milk production of dairy cows were studied. Papers were selected only if at least 2 PM were compared under similar experimental conditions, particularly the same pasture allowance (SPA). The final database included 15 papers with 27 PM comparisons. For analytical purposes, the database was subdivided into 3 subsets that varied according to the estimation height at which pasture allowance was determined; that is, where PM were compared at the SPA above ground level (SPA(0) subset), above 2 to 3 cm (SPA(3) subset), and above 4 to 5 cm (SPA(5) subset). Statistical analyses were conducted on the entire database (global analysis) and within each subset using linear model procedures. An interaction between PM and estimation height was found for pasture intake and milk production in the global analysis. On the basis of the predictive equations, pasture intake increased by 1.58 kg of dry matter/d per tonne increase in PM when PM were compared at SPA(0), was not affected by PM when PM were compared at SPA(3), and decreased by 0.65 kg of dry matter/d per tonne increase in PM when PM were compared at SPA(5). This is consistent with the effect of PM on milk production, which was positive and negative (1.04 and -0.79 kg/t of PM, respectively) when PM were compared at SPA(0) and SPA(5), respectively. Grazing time was only slightly affected by PM, irrespective of estimation height, because the effect of PM on pasture intake was mainly dependent on the variation

  4. Assessment of Prior Grazing Experiences on Adaption to Pasture and Performance of Dairy Heifers.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to evaluate how previous grazing experience affects animal behavior on pasture. Animal behavior was monitored in 32 Holstein (n = 21) and Holstein-Jersey (n = 11) yearlings. Two heifer groups (n = 8 per group) had been exposed to pasture from August through October 20...

  5. Riparian land-use and stream bank erosion within grazed pastures in southern Iowa, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Riparian land-uses such as cropping and grazing are major agricultural practices that have impacts on stream bank erosion. The aim of this study is to assess the effects of riparian land use considered in both field and catchment scale on stream bank erosion within grazed riparian pasture sites in t...

  6. Intensive cattle grazing affects pasture litter-fall: an unrecognized nitrous oxide source.

    PubMed

    Pal, Pranoy; Clough, Tim J; Kelliher, Francis M; van Koten, Chikako; Sherlock, Robert R

    2012-01-01

    The rationale for this study came from observing grazing dairy cattle dropping freshly harvested plant material onto the soil surface, hereafter called litter-fall. The Intergovernmental Panel on Climate Change (IPCC) guidelines include NO emissions during pasture renewal but do not consider NO emissions that may result from litter-fall. The objectives of this study were to determine litter-fall rates and to assess indicative NO emission factors (EFs) for the dominant pasture species (perennial ryegrass [ L.] and white clover [ L.]). Herbage was vacuumed from intensively managed dairy pastures before and after 30 different grazing events when cows (84 cows ha) grazed for 24 h according to a rotational system; the interval between grazing events ranged from 21 to 30 d. A laboratory incubation study was performed to assess potential EF values for the pasture species at two soil moisture contents. Finely ground pasture material was incubated under controlled laboratory conditions with soil, and the NO emissions were measured until rates returned to control levels. On average, pre- and postgrazing dry matter yields per grazing event were 2516 ± 636 and 1167 ± 265 kg DM ha (±SD), respectively. Pregrazing litter was absent, whereas postgrazing fresh and senesced litter-fall rates were 53 ± 24 and 19 ± 18 kg DM ha, respectively. Annually, the rotational grazing system resulted in 12 grazing events where fresh litter-fall equaed to 16 kg N ha yr to the soil. Emission factors in the laboratory experiment indicated that the EF for perennial ryegrass and white clover ranged from 0.7 to 3.1%. If such EF values should also occur under field conditions, then we estimate that litter-fall induces an NO emission rate of 0.3 kg NO ha yr. Litter-fall as a source of NO in grazed pastures requires further assessment.

  7. Meta-analysis of the effect of pasture allowance on pasture intake, milk production, and grazing behavior of dairy cows grazing temperate grasslands.

    PubMed

    Pérez-Prieto, L A; Delagarde, R

    2013-10-01

    Daily pasture allowance (PA) is defined as the product of pregrazing pasture mass and offered area, and is the major grazing management factor determining pasture utilization per unit area and daily performance of grazing dairy cows. The objective of the present study was to perform a meta-analysis reviewing the effect of PA on pasture intake, milk production, milk composition, and grazing behavior of dairy cows. Experiments studying the effect of PA on pasture intake or milk production, which eventually included milk composition or grazing behavior data, or both, were selected to create a database. Papers were selected only if at least 2 PA were compared under the same experimental conditions, particularly the same pasture mass (i.e., where PA levels were only obtained through changes in daily offered area). The final database included 97 PA comparisons reported in 56 papers. For analytical purposes, the database was subdivided into 3 subsets that varied according to the estimation height (EH) at which PA was determined; that is, PA above ground level (PA₀ subset), PA above 2.5 to 3.5 cm (PA₃ subset), and PA above 4 to 5 cm (PA₅ subset). Statistical analyses were conducted independently on the PA₀, PA₃, and PA₅ subsets and on the whole database (global analysis) by using linear and nonlinear mixed-model procedures. The curves, either exponential, quadratic, or linear, describing the effects of PA on pasture intake, milk production, or grazing behavior of dairy cows are conceptually similar, whatever the EH. The equations describing these curves are, however, specific for each EH. Accordingly, from typical low to high PA, the increase in pasture intake (0.13 vs. 0.21 vs. 0.28 kg/kg of PA), milk production (0.11 vs. 0.17 vs. 0.24 kg/kg of PA), and milk solids production (0.008 vs. 0.010 vs. 0.013 kg/kg of PA) per kilogram of increase in PA was lower for PA₀ than for PA₃, and for PA₃ than for PA₅. Grazing time increased from low to medium PA and

  8. FORAGES AND PASTURES SYMPOSIUM: Improving soil health and productivity on grasslands using managed grazing of livestock.

    PubMed

    Russell, J R; Bisinger, J J

    2015-06-01

    Beyond grazing, managed grasslands provide ecological services that may offer economic incentives for multifunctional use. Increasing biodiversity of plant communities may maximize net primary production by optimizing utilization of available light, water, and nutrient resources; enhance production stability in response to climatic stress; reduce invasion of exotic species; increase soil OM; reduce nutrient leaching or loading in surface runoff; and provide wildlife habitat. Strategically managed grazing may increase biodiversity of cool-season pastures by creating disturbance in plant communities through herbivory, treading, nutrient cycling, and plant seed dispersal. Soil OM will increase carbon and nutrient sequestration and water-holding capacity of soils and is greater in grazed pastures than nongrazed grasslands or land used for row crop or hay production. However, results of studies evaluating the effects of different grazing management systems on soil OM are limited and inconsistent. Although roots and organic residues of pasture forages create soil macropores that reduce soil compaction, grazing has increased soil bulk density or penetration resistance regardless of stocking rates or systems. But the effects of the duration of grazing and rest periods on soil compaction need further evaluation. Because vegetative cover dissipates the energy of falling raindrops and plant stems and tillers reduce the rate of surface water flow, managing grazing to maintain adequate vegetative cover will minimize the effects of treading on water infiltration in both upland and riparian locations. Through increased diversity of the plant community with alterations of habitat structure, grazing systems can be developed that enhance habitat for wildlife and insect pollinators. Although grazing management may enhance the ecological services provided by grasslands, environmental responses are controlled by variations in climate, soil, landscape position, and plant community

  9. FORAGES AND PASTURES SYMPOSIUM: Improving soil health and productivity on grasslands using managed grazing of livestock.

    PubMed

    Russell, J R; Bisinger, J J

    2015-06-01

    Beyond grazing, managed grasslands provide ecological services that may offer economic incentives for multifunctional use. Increasing biodiversity of plant communities may maximize net primary production by optimizing utilization of available light, water, and nutrient resources; enhance production stability in response to climatic stress; reduce invasion of exotic species; increase soil OM; reduce nutrient leaching or loading in surface runoff; and provide wildlife habitat. Strategically managed grazing may increase biodiversity of cool-season pastures by creating disturbance in plant communities through herbivory, treading, nutrient cycling, and plant seed dispersal. Soil OM will increase carbon and nutrient sequestration and water-holding capacity of soils and is greater in grazed pastures than nongrazed grasslands or land used for row crop or hay production. However, results of studies evaluating the effects of different grazing management systems on soil OM are limited and inconsistent. Although roots and organic residues of pasture forages create soil macropores that reduce soil compaction, grazing has increased soil bulk density or penetration resistance regardless of stocking rates or systems. But the effects of the duration of grazing and rest periods on soil compaction need further evaluation. Because vegetative cover dissipates the energy of falling raindrops and plant stems and tillers reduce the rate of surface water flow, managing grazing to maintain adequate vegetative cover will minimize the effects of treading on water infiltration in both upland and riparian locations. Through increased diversity of the plant community with alterations of habitat structure, grazing systems can be developed that enhance habitat for wildlife and insect pollinators. Although grazing management may enhance the ecological services provided by grasslands, environmental responses are controlled by variations in climate, soil, landscape position, and plant community

  10. Pasture soils contaminated with fertilizer-derived cadmium and fluorine: livestock effects.

    PubMed

    Loganathan, Paripurnanda; Hedley, Mike J; Grace, Neville D

    2008-01-01

    Fertilizers are indispensable for ensuring sustainability of agricultural production, thereby achieving food and fiber security. Nitrogen, sulfur, and potassium fertilizers are relatively free of impurities, but phosphorus (P) fertilizers, the main fertilizer input for the economic production of legume-based pastures, contain several contaminants, of which F and Cd are considered to be of most concern because they have potentially harmful effects on soil quality, livestock health, and food safety. Incidences of fluorosis in grazing livestock, and accumulation of Cd in the edible offal products of livestock, above the maximum permissible concentration set by food authorities have been reported in many countries. The majority of Cd and F applied to pastures in many countries continues to accumulate in the biologically active topsoil due to strong adsorption to soil constituents. However, the rate of Cd accumulation in the last decade has slowed as a result of selective use of low-Cd fertilizers. Cd and F adsorption in soils increase with increased contents of iron and aluminium oxides, layer silicates and allophane in soils, and increased soil pH. Cadmium adsorption also increases with increased Mn oxides and organic matter in soil. However, some Cd will be released during decomposition of plant and animal remains and organic matter. In most pastoral soils the majority of Cd and F added in fertilizers remains in the topsoil and little moves below 20-30 cm, and therefore these are unlikely to contaminate groundwater. However, F may pose a risk to shallow groundwater in very acidic low-P-fixing soils, and Cd may pose a risk in very acidic soils containing low organic matter and clay contents, or in soils with high chloride concentrations. Research is required both to test whether groundwater beneath farms with long histories of P fertilizer use is contaminated by these elements and also to examine their mechanisms of movement. Cd intake by grazing livestock occurs

  11. Pasture intake and milk production of dairy cows rotationally grazing on multi-species swards.

    PubMed

    Roca-Fernández, A I; Peyraud, J L; Delaby, L; Delagarde, R

    2016-09-01

    Increasing plant species diversity has been proposed as a means for enhancing annual pasture productivity and decreasing seasonal variability of pasture production facing more frequent drought scenarios due to climate change. Few studies have examined how botanical complexity of sown swards affects cow performance. A 2-year experiment was conducted to determine how sward botanical complexity, from a monoculture of ryegrass to multi-species swards (MSS) (grasses-legumes-forb), affect pasture chemical composition and nutritive value, pasture dry matter (DM) intake, milk production and milk solids production of grazing dairy cows. Five sward species: perennial ryegrass (L as Lolium), white clover and red clover (both referred to as T as Trifolium because they were always sown together), chicory (C as Cichorium) and tall fescue (F as Festuca) were assigned to four grazing treatments by combining one (L), three (LT), four (LTC) or five (LTCF) species. Hereafter, the LT swards are called mixed swards as a single combination of ryegrass and clovers, whereas LTC and LTCF swards are called MSS as a combination of at least four species from three botanical families. The experimental area (8.7 ha) was divided into four block replicates with a mineral nitrogen fertilisation of 75 kg N/ha per year for each treatment. In total, 13 grazing rotations were carried out by applying the same grazing calendar and the same pasture allowance of 19 kg DM/cow per day above 4 cm for all treatments. Clover represented 20% of DM for mixed and MSS swards; chicory represented 30% of DM for MSS and tall fescue represented 10% of DM for LTCF swards. Higher milk production (+1.1 kg/day) and milk solids production (+0.08 kg/day) were observed for mixed swards than for ryegrass swards. Pasture nutritive value and pasture DM intake were unaffected by the inclusion of clover. Pasture DM, organic matter and NDF concentrations were lower for MSS than for mixed swards. Higher milk production (+0.8 kg

  12. Effects of grazing intensity and chemical seedhead suppression on steers grazing tall fescue pastures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The first year of a 2 yr grazing study was conducted to evaluate use of Chaparral™ to suppress reproductive growth in tall fescue grazed with low and moderate grazing intensities. Chaparral applications (0 and 2.0 oz/acre) and grazing intensities were arranged as RCBD with three replications. Variab...

  13. Reduction of nitrate leaching with haying or grazing and omission of nitrogen fertilizer.

    PubMed

    Owens, L B; Bonta, J V

    2004-01-01

    In some high-fertility, high-stocking-density grazing systems, nitrate (NO(3)) leaching can be great, and ground water NO(3)-N concentrations can exceed maximum contaminant levels. To reduce high N leaching losses and concentrations, alternative management practices need to be used. At the North Appalachian Experimental Watershed near Coshocton, OH, two management practices were studied with regard to reducing NO(3)-N concentrations in ground water. This was following a fertilized, rotational grazing management practice from which ground water NO(3)-N concentrations exceeded maximum contaminant levels. Using four small watersheds (each approximately 1 ha), rotational grazing of a grass forage without N fertilizer being applied and unfertilized grass forage removed as hay were used as alternative management practices to the previous fertilized pastures. Ground water was sampled at spring developments, which drained the watershed areas, over a 7-yr period. Peak ground water NO(3)-N concentrations before the 7-yr study period ranged from 13 to 25.5 mg L(-1). Ground water NO(3)-N concentrations progressively decreased under each watershed and both management practices. Following five years of the alternative management practices, ground water NO(3)-N concentrations ranged from 2.1 to 3.9 mg L(-1). Both grazing and haying, without N fertilizer being applied to the forage, were similarly effective in reducing the NO(3)-N levels in ground water. This research shows two management practices that can be effective in reducing high NO(3)-N concentrations resulting from high-fertility, high-stocking-density grazing systems, including an option to continue grazing. PMID:15254104

  14. The potential for avermectins to affect the nutrient economy of grazed pastures.

    PubMed

    King, K L

    1993-06-01

    This examination of the potential ecotoxic effects of the avermectins in temperature pastures grazed by sheep is based on a community approach and is focussed on one important aspect of ecosystem function, the nutrient cycle. Data on the amount and distribution of sheep dung on pastures grazed at different stocking rates indicated that areas of high stocking and sheep camps would be affected by avermectin residues to the greatest extent. Mineral losses from sheep dung which does not contain ivermectin, have been examined to provide a background against which the potential effects of avermectins on nutrient cycling can be appraised. The source of the diet is important; for example, dung from sheep grazing on improved pasture loses sulphur faster, and has higher microbial activity, than that of native pasture, regardless of whether it is fresh or old. Dung-dwelling fauna such as dung beetles and microarthropods are most abundant in areas of high dung concentration and microbial activity is greatest in sheep camps where a large quantity of excreta is voided. However, while there is evidence that avermectin does affect certain of the larger dung-dwelling fauna, little is known of its effects on the smaller invertebrate biota such as free-living nematodes and microarthropods. Calculations for phosphorus budgets on both native and improved pastures indicate that the amount of phosphorus recycled in these systems could be reduced by up to 5% the dosage levels currently recommended for the drug. PMID:8346639

  15. Grazing management effects on stream bank erosion and phosphorus delivery to a pasture stream

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pasture lands may deliver significant sediment and phosphorus (P) to surface waters. To determine the effects of beef (Bos taurus) grazing practices on stream bank erosion and P losses, three treatments [rotational stocking (RS), continuous stocking with restricted stream access (CSR), and continuou...

  16. Yield and soil carbon sequestration in grazed pastures sown with two or five forage species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing plant species richness is often associated with an increase in productivity and associated ecosystem services such as soil C sequestration. In this paper we report on a nine-year experiment to evaluate the relative forage production and C sequestration potential of grazed pastures sown to...

  17. Streambank Erosion from Grazed Pastures, Grass Filters and Forest Buffers Over a Six-Year Period

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In agricultural landscapes, streambank erosion, as a source of non-point water pollution, is one of the major contributors to stream habitat degradation. Streambank erosion rates from riparian forest buffers, grass filters and grazed pastures (stocking rates ranged from 0.23 to 1.15 cow-days ha-1 m-...

  18. Carbon sequestration potential of grazed pasture depends on prior management history

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Grazed pastures are often assumed to be net sinks for removing carbon dioxide from the atmosphere and thus, are promoted as a management practice that can help mitigate climate change. The ability to serve as a C sink is especially pronounced following a history of tillage and row crop production. I...

  19. Forage intake and digestion by cattle grazing midgrass prairie rangeland or sideoats grama/sweetclover pasture.

    PubMed

    Gunter, S A; McCollum, F T; Gillen, R L; Krysl, L J

    1993-12-01

    In mid-May, beef cattle fitted with esophageal (four steers/pasture) or ruminal and duodenal cannulas (six heifers/pasture; 274 +/- 6 kg BW +/- SE) grazed midgrass prairie (excellent range condition; PRAIRIE) or a seeded mixture of sideoats grama (48% of pasture DM) and sweetclover (6% of pasture DM; Bouteloua curtipendula [Michx.] Torr./Melilotus officinalis [L.] Lam.; PASTURE). Masticate NDF, ADF, and in vitro OM disappearance did not differ (P > .11) between forage types (average = 66.6, 36.1, and 58.8% of OM). Only N differed (P = .02) between PRAIRIE (2.1) and PASTURE (2.4% of OM). Extents of in situ OM and N disappearance were greater (P < .05) and rate of N disappearance between 12 and 36 h was slower (P < .10) from PRAIRIE than from PASTURE masticate. Based on in situ data, the ruminally degraded N: ruminally degraded OM (grams/kilogram) ratio differed (P < .05) between PRAIRIE (22) and PASTURE (25). Ruminal ammonia N concentration (milligrams/deciliter) was less (P = .02) for PRAIRIE (2.8) than for PASTURE (3.8). Forage OM intake and fecal OM output did not differ (P > .72; average = 8,207 and 3,380 g/d), but duodenal OM flow tended (P = .13) to be greater (PRAIRIE = 4,892, PASTURE = 5,170 g/d) in cattle grazing PASTURE. Apparent and true ruminal OM digestion did not differ between forage types (P > .18; average = 38.3 and 48.5%). Nitrogen intake, nonammonia N, and forage N flow at the duodenum were greater (P < .04) for PASTURE (198 vs 171, 242 vs 210, and 162 vs 135 g/d) than for PRAIRIE. Microbial N flow (average = 78 g/d) and microbial efficiency (average = 20 g of microbial N/kg of OM truly fermented) did not differ (P > .25) between forage types. Apparent and true ruminal N digestion did not differ (P > .65; average = -26.6 and 19.3%) between forage types. Flow of nonammonia N was in excess relative to digestible OM intake; hence, digestible OM intake seemed to be first-limiting for performance by cattle grazing either forage type.

  20. CO2 balance of an intensively grazed temperate pasture during pasture renewal via cultivation or direct drilling

    NASA Astrophysics Data System (ADS)

    Rutledge, Susanna; Mudge, Paul; Wall, Aaron; Campbell, Dave; Schipper, Louis

    2015-04-01

    The management practice of pasture renewal (PR, also referred to as 'restoration') of permanent pastures offers the opportunity to replace low producing pasture, remove weeds and pests, improve drainage, and introduce improved pasture varieties, thereby increasing pasture production. PR can consist of a range of practices including spraying existing pasture with herbicide, followed by direct drilling or full cultivation (ploughing). Although PR is common in some farming systems, little is known about the impact of PR of permanent pastures on soil C and CO2 dynamics. Here we report on the CO2 balance following four PR events of intensively grazed permanent pastures in temperate New Zealand. Three events of PR followed the same method which included two herbicide sprays and a full cultivation (CULT). PR events took place in either spring or autumn, which meant soil moisture conditions varied greatly between PR events. For the fourth PR event, pasture was sprayed only once, and was not cultivated but instead seeds were directly drilled (DD) into the sprayed-off pasture. Chambers and the eddy covariance technique were used to measure the CO2 exchange before, during and after PR. In addition to the direct loss of CO2 measured during the PR events, we also quantified the 'net impact of PR' which we defined as the difference between net CO2 exchange of the pasture that underwent PR and that of an undisturbed pasture which served as a control. This way, we also accounted for the temporary lack of photosynthetic carbon inputs when plants were absent during the PR events. Both the rate of direct CO2 respiratory losses and the 'net impact of PR' appeared highly dependent on soil moisture status, with the lowest rate of loss measured under severe drought conditions and the highest rate of loss measured in spring when ample moisture was present. Because the rate of CO2 loss did not decrease over time during PR, the longer the soil was bare, the more CO2 was lost. The duration

  1. Grazing alters net ecosystem C fluxes and the net global warming potential of a subtropical pasture

    NASA Astrophysics Data System (ADS)

    Gomez-Casanovas, N.; DeLucia, N.; DeLucia, E. H.; Boughton, E.; Garrett, J. C.; Keel, E.; Bernacchi, C.

    2015-12-01

    The impact of grazing on CO2 and CH4 fluxes from subtropical pastures and thus on the climate system is uncertain, although these systems account for a substantial portion of global carbon storage. We investigated how cattle grazing affects net ecosystem CO2 exchange (NEE) and CH4 emissions in subtropical pastures using the eddy covariance technique over two complete wet-dry seasonal cycles. Grazing increased soil wetness but did not affect soil temperature. By removing aboveground biomass, grazing consistently decreased gross primary productivity (16% and 8 % in 2013-2014 and 2014-2015) and reduced ecosystem respiration (Re, 20% and 38% in 2013-2014 and 2014-2015). Lower Re in grazed (GP) than in ungrazed pasture (UP) was also explained by decreased soil and heterotrophic respiration and root biomass. Grazing increased the net CO2 sink strength of the pasture (-86 ± 5 gC m-2 yr-1 in GP vs. -76 ± 6 gC m-2 yr-1 in UP in 2013-2014; -118 ± 9 gC m-2 yr-1 in GP vs. +142 ± 6 gC m-2 yr-1 UP in 2014-2015). Over both wet-dry seasonal cycles, both ecosystems were net sources of CH4, and variations in fluxes without cattle present were driven by changes in soil wetness and temperature. The presence of cattle and greater soil moisture cased by the removal of aboveground biomass, caused greater total net ecosystem CH4 emissions from GP than from UP (16% and 8 % in 2013-2014 and 2014-2015). Wetter soils under GP were responsible for 21-56% of the difference in net CH4 emissions between pastures, suggesting that enhanced CH4 production from wetter soils due to cattle presence can be a major contributor to annual CH4 fluxes. Combining CO2 and CH4 to calculate a C budget revealed that grazing increased the net C sink strength of the pasture (-72 gC m-2 yr-1 in GP vs. -66 gC m-2 yr-1 in UP in 2013-2014; -114 gC m-2 yr-1 in GP vs. +144 gC m-2 yr-1 in UP in 2014-2015). Accounting for NEE and the radiative forcing of CH4, grazing increased the net global warming potential (GWP) of

  2. Comparison of management intensive grazing and continuous grazing in beef cattle pasture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Management intensive grazing (MIG) offers the potential to increase the financial profitability and productivity of grazing beef and dairy farms in Appalachian Ohio, with minimum environmental impacts. The objective of the project was to compare MIG with conventional continuous grazing (CG) and rela...

  3. Pasture-scale methane emissions of grazing cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Grazing cattle are mobile point sources of methane and present challenges to quantify emissions using noninterfering micrometeorological methods. Stocking density is low and cattle can bunch up or disperse over a wide area, so knowing cattle locations is critical. The methane concentration downwind ...

  4. Impacts of Rotational Grazing on Soil Carbon in Native Grass-Based Pastures in Southern Australia.

    PubMed

    Sanderman, Jonathan; Reseigh, Jodie; Wurst, Michael; Young, Mary-Anne; Austin, Jenet

    2015-01-01

    Rotational grazing management strategies have been promoted as a way to improve the sustainability of native grass-based pasture systems. From disturbance ecology theory, rotational grazing relative to continuous grazing can increase pasture productivity by allowing vegetation to recover after short intense grazing periods. This project sought to assess whether soil organic carbon (SOC) stocks would also increase with adoption of rotational grazing management. Twelve pairs of rotationally and continuously grazed paddocks were sampled across a rainfall gradient in South Australia. Pasture productivity approximated as the normalized difference vegetation index (NDVI) was on average no different between management categories, but when the data from all sites were aggregated as log response ratios (rotational/continuous) a significant positive trend of increasing NDVI under rotational grazing relative to continuous grazing was found (R2 = 0.52). Mean SOC stocks (0-30 cm) were 48.3 Mg C ha-1 with a range of 20-80 Mg C ha-1 across the study area with no differences between grazing management categories. SOC stocks were well correlated with rainfall and temperature (multiple linear regression R2 = 0.61). After removing the influence of climate on SOC stocks, the management variables, rest periods, stocking rate and grazing days, were found to be significantly correlated with SOC, explaining 22% of the variance in SOC, but there were still no clear differences in SOC stocks at paired sites. We suggest three reasons for the lack of SOC response. First, changes in plant productivity and turnover in low-medium rainfall regions due to changes in grazing management are small and slow, so we would only expect at best small incremental changes in SOC stocks. This is compounded by the inherent variability within and between paddocks making detection of a small real change difficult on short timescales. Lastly, the management data suggests that there is a gradation in

  5. How to determine the GHG budget of a pasture field with grazing animals

    NASA Astrophysics Data System (ADS)

    Ammann, Christof; Neftel, Albrecht; Felber, Raphael

    2016-04-01

    Up to now the scientific investigation and description of the agriculture related greenhouse gas (GHG) exchange has been largely separated into (i) direct animal related and (ii) ecosystem area related processes and measurement methods. An overlap of the two usually separated topics occurs for grazed pastures, where direct animal and pasture area emissions are relevant. In the present study eddy covariance (EC) flux measurements on the field scale were combined with a source location attribution (footprint) model and with GPS position measurements of the individual animals. The experiment was performed on a pasture field in Switzerland under a rotational full grazing regime with dairy cows. The exchange fluxes of CH4, CO2, and N2O were measured simultaneously over the entire year. The observed CH4 emission fluxes correlated well with the presence of cows in the flux footprint. When converted to average emission per cow, the results agreed with published values from respiration chamber experiments with similar cows. For CO2 a sophisticated partitioning algorithm was applied to separate the pasture and animal contributions, because both were in the same order of magnitude. The N2O exchange fully attributable to the pasture soil showed considerable and continuous emissions through the entire seasonal course mainly modulated by soil moisture and temperature. The resulting GHG budget shows that the largest GHG effect of the pasture system was due to enteric CH4 emissions followed by soil N2O emissions, but that the carbon storage change was affected by a much larger uncertainty. The results demonstrate that the EC technique in combination with animal position information allows to consistently quantify the exchange of all three GHG on the pasture and to adequately distinguish between direct animal and diffuse area sources (and sinks). Yet questions concerning a standardized attribution of animal related emissions to the pasture GHG budget still need to be resolved.

  6. Keratinophilic fungi isolated from soils of long-term fold-grazed, degraded pastures in national parks of Slovakia.

    PubMed

    Javoreková, Soňa; Labuda, Roman; Maková, Jana; Novák, Ján; Medo, Juraj; Majerčíková, Kamila

    2012-09-01

    A total of 939 isolates of 11 genera representing 15 species of keratinophilic fungi were isolated and identified from the soils of three long-term fold-grazed pastures in national parks of Slovakia (Pod Ploskou, Strungový príslop, and Pod Kečkou) and one non-fold-grazed pasture in sierra Stolicke vrchy (Diel) using the hair-baiting technique. Keratinophilic fungi were present in all soil samples with a prevalence of Trichophyton ajelloi and Paecilomyces lilacinus. These fungi were more abundant in soil from fold-grazed pasture (Strungový príslop) compared to non-fold-grazed pasture (Diel). The occurrence of the other keratinophilic fungi was substantially lower, likely because of low pH in some soils.

  7. [Photosensitization in cattle grazing on pastures of Brahciaria decumbens Stapf infested with Pithomyces chartarum (Berk. & Curt.) M.B. Ellis].

    PubMed

    Andrade, S O; da Silva Lopes, H O; de Almeida Barros, M; Leite, G G; Dias, S M; Saueressig, M; Nobre, D; Temperini, J A

    1978-01-01

    Aspects of photosensitization in bovines grazing on pastures of Brachiaria decumbens Stapf infested with Pithomyces chartarum (Berk. & Curt.) M.B. Ellis infested all pastures 45(2):117-136, 1978. This paper reports experimental studies on photosensitization in bovines grazing on different pastures of Brachiaria decumbens Stapf in the "Cerrados" region (Planaltina, DF). Climatic conditions, zinc content and occurence of fungi on pastures were investigated. Pithomyces chartarum (Berk. & Curt.) M.B. Ellis infested all pastures examined. Photosensitization was observed in one animal maintained on a pasture of B. decumbens formed with seeds from Australia. Clinical and necropsy data were similar to those related in literature for sporidesmin-intoxicated animals. An isolate of P. chartarum and samples of bovine bile were assayed for sporidesmin presence.

  8. [Photosensitization in cattle grazing on pastures of Brahciaria decumbens Stapf infested with Pithomyces chartarum (Berk. & Curt.) M.B. Ellis].

    PubMed

    Andrade, S O; da Silva Lopes, H O; de Almeida Barros, M; Leite, G G; Dias, S M; Saueressig, M; Nobre, D; Temperini, J A

    1978-01-01

    Aspects of photosensitization in bovines grazing on pastures of Brachiaria decumbens Stapf infested with Pithomyces chartarum (Berk. & Curt.) M.B. Ellis infested all pastures 45(2):117-136, 1978. This paper reports experimental studies on photosensitization in bovines grazing on different pastures of Brachiaria decumbens Stapf in the "Cerrados" region (Planaltina, DF). Climatic conditions, zinc content and occurence of fungi on pastures were investigated. Pithomyces chartarum (Berk. & Curt.) M.B. Ellis infested all pastures examined. Photosensitization was observed in one animal maintained on a pasture of B. decumbens formed with seeds from Australia. Clinical and necropsy data were similar to those related in literature for sporidesmin-intoxicated animals. An isolate of P. chartarum and samples of bovine bile were assayed for sporidesmin presence. PMID:573108

  9. Eddy covariance methane flux measurements over a grazed pasture: effect of cows as moving point sources

    NASA Astrophysics Data System (ADS)

    Felber, R.; Münger, A.; Neftel, A.; Ammann, C.

    2015-06-01

    Methane (CH4) from ruminants contributes one-third of global agricultural greenhouse gas emissions. Eddy covariance (EC) technique has been extensively used at various flux sites to investigate carbon dioxide exchange of ecosystems. Since the development of fast CH4 analyzers, the instrumentation at many flux sites has been amended for these gases. However, the application of EC over pastures is challenging due to the spatially and temporally uneven distribution of CH4 point sources induced by the grazing animals. We applied EC measurements during one grazing season over a pasture with 20 dairy cows (mean milk yield: 22.7 kg d-1) managed in a rotational grazing system. Individual cow positions were recorded by GPS trackers to attribute fluxes to animal emissions using a footprint model. Methane fluxes with cows in the footprint were up to 2 orders of magnitude higher than ecosystem fluxes without cows. Mean cow emissions of 423 ± 24 g CH4 head-1 d-1 (best estimate from this study) correspond well to animal respiration chamber measurements reported in the literature. However, a systematic effect of the distance between source and EC tower on cow emissions was found, which is attributed to the analytical footprint model used. We show that the EC method allows one to determine CH4 emissions of cows on a pasture if the data evaluation is adjusted for this purpose and if some cow distribution information is available.

  10. Relationship between pasture nutritive measurements and plasma urea nitrogen in lambs grazing silvopasture or open pasture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The relationship of herbage energy content relative to crude protein (CP) is an important aspect in nitrogen use efficiency of grazing livestock. Plasma urea nitrogen (PUN) is an excellent indicator of animal nitrogen status, increasing when excessive nitrogen is available in the diet, and resultin...

  11. Animal and pasture responses to grazing management of chemically suppressed tall fescue in mixed pastures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Treatment of toxic endophyte-infected tall fescue [Lolium arundinaceum (Schreb.) Darbysh] with metsulfuran-methyl can mitigate fescue toxicosis and enhance forage nutritive value by suppressing seedhead emergence. A grazing experiment was conducted with steers (2013) and heifers (2014) to evaluate a...

  12. Eddy covariance methane flux measurements over a grazed pasture: effect of cows as moving point sources

    NASA Astrophysics Data System (ADS)

    Felber, R.; Münger, A.; Neftel, A.; Ammann, C.

    2015-02-01

    Methane (CH4) from ruminants contributes one third to global agricultural greenhouse gas emissions. Eddy covariance (EC) technique has been extensively used at various flux sites to investigate carbon dioxide exchange of ecosystems. Since the development of fast CH4 analysers the instrumentation at many flux sites have been amended for these gases. However the application of EC over pastures is challenging due to the spatial and temporal uneven distribution of CH4 point sources induced by the grazing animals. We applied EC measurements during one grazing season over a pasture with 20 dairy cows (mean milk yield: 22.7 kg d-1) managed in a rotational grazing system. Individual cow positions were recorded by GPS trackers to attribute fluxes to animal emissions using a footprint model. Methane fluxes with cows in the footprint were up to two orders of magnitude higher than ecosystem fluxes without cows. Mean cow emissions of 423 ± 24 g CH4 head-1 d-1 (best guess of this study) correspond well to animal respiration chamber measurements reported in the literature. However a systematic effect of the distance between source and EC tower on cow emissions was found which is attributed to the analytical footprint model used. We show that the EC method allows to determine CH4 emissions of grazing cows if the data evaluation is adjusted for this purpose and if some cow distribution information is available.

  13. Effect of pre-grazing herbage mass on dairy cow performance, grass dry matter production and output from perennial ryegrass (Lolium perenne L.) pastures.

    PubMed

    Wims, C M; Delaby, L; Boland, T M; O'Donovan, M

    2014-01-01

    A grazing study was undertaken to examine the effect of maintaining three levels of pre-grazing herbage mass (HM) on dairy cow performance, grass dry matter (DM) production and output from perennial ryegrass (Lolium perenne L.) pastures. Cows were randomly assigned to one of three pre-grazing HM treatments: 1150 - Low HM (L), 1400 - Medium HM (M) or 2000 kg DM/ha - High HM (H). Herbage accumulation under grazing was lowest (P<0.01) on the L treatment and cows grazing the L pastures required more grass silage supplementation during the grazing season (+73 kg DM/cow) to overcome pasture deficits due to lower pasture growth rates (P<0.05). Treatment did not affect daily milk production or pasture intake, although cows grazing the L pastures had to graze a greater daily area (P<0.01) and increase grazing time (P<0.05) to compensate for a lower pre-grazing HM (P<0.01). The results indicate that, while pre-grazing HM did not influence daily milk yield per cow, adapting the practise of grazing low HM (1150 kg DM/ha) pasture reduces pasture DM production and at a system level may increase the requirement for imported feed.

  14. Using normalized difference vegetation index to estimate carbon fluxes from small rotationally grazed pastures

    USGS Publications Warehouse

    Skinner, R.H.; Wylie, B.K.; Gilmanov, T.G.

    2011-01-01

    Satellite-based normalized difference vegetation index (NDVI) data have been extensively used for estimating gross primary productivity (GPP) and yield of grazing lands throughout the world. However, the usefulness of satellite-based images for monitoring rotationally-grazed pastures in the northeastern United States might be limited because paddock size is often smaller than the resolution limits of the satellite image. This research compared NDVI data from satellites with data obtained using a ground-based system capable of fine-scale (submeter) NDVI measurements. Gross primary productivity was measured by eddy covariance on two pastures in central Pennsylvania from 2003 to 2008. Weekly 250-m resolution satellite NDVI estimates were also obtained for each pasture from the moderate resolution imaging spectroradiometer (MODIS) sensor. Ground-based NDVI data were periodically collected in 2006, 2007, and 2008 from one of the two pastures. Multiple-regression and regression-tree estimates of GPP, based primarily on MODIS 7-d NDVI and on-site measurements of photosynthetically active radiation (PAR), were generally able to predict growing-season GPP to within an average of 3% of measured values. The exception was drought years when estimated and measured GPP differed from each other by 11 to 13%. Ground-based measurements improved the ability of vegetation indices to capture short-term grazing management effects on GPP. However, the eMODIS product appeared to be adequate for regional GPP estimates where total growing-season GPP across a wide area would be of greater interest than short-term management-induced changes in GPP at individual sites.

  15. Green leaf allowance and dairy ewe performance grazing on tropical pasture.

    PubMed

    De Souza, J; Batistel, F; Ticiani, E; Sandri, E C; Pedreira, C G S; Oliveira, D E

    2014-06-01

    pattern in responses to GLA levels as reported in the literature with temperate pastures, the magnitude of the process changed and the maximum response in milk yield from lactating dairy ewes grazing a tropical pasture would be achieved with higher forage allowances than in temperate pastures. Overall, Aruana guineagrass grazed by lactating dairy ewes should be managed to provide 7 to 10 GLA in kg DM/100 kg BW according to the production goals.

  16. High intensity, short duration rotational grazing on reclaimed cool season fescue/legume pastures: I. System development

    SciTech Connect

    Erickson, W.R.; Carlson, K.E.

    1995-09-01

    The Pittsburg & Midway Coal Mining Co.`s ({open_quotes}P&M{close_quotes}) Midway Mine lies 50 miles south of Kansas City, Kansas, straddling the border of Kansas and Missouri. P&M actively mined the area until 1989, when the mine was closed and reclaimed. Approximately 3,750 acres of surface mined land were topsoiled and revegetated to cool season fescue/legume pasture. Various pasture management methods are being utilized to meet reclamation success standards and achieve final bond release. The effectiveness and costs of various cool season fescue/legume pasture management methods are evaluated and contrasted. These methods include sharecropping, bush hogging, burning and livestock grazing. It presents guidelines used to develop a site specific rotational livestock grazing programs with land owners or contractors, and local, state and federal agencies. Rotational grazing uses both cow/calf or feeder livestock operations. Key managerial elements used to control grazing activities, either by the landowner or a contractor, are reviewed. Methods used to determine stocking levels for successful rotational grazing on this type of pasture are presented. Rotational grazing of livestock has proven to be the most effective method for managing established cool season fescue/legume pastures at this site. Initial stocking rates of 1 A.U.M. per 5 acres have been modified to a current stocking rate of 1 A.U.M. per 2.5 acres. Supporting physical and chemical data are presented and discussed.

  17. Urea metabolism in beef steers grazing bermudagrass, caucasian bluestem, or gamagrass pastures varying in plant morphology, protein content, and protein composition.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our objective was to evaluate pastures of bermudagrass (Cynodon dactylon, BG), caucasian bluestem (Bothriochloa caucasica, CBS), and gamagrass (Tripsacum dactyloides, GG) from the perspectives of forage composition, selection during grazing, and N metabolism in beef steers. All pastures were ferti...

  18. Case study of a commercial sheep flock under extensive mountain grazing: Pasture derived lipid compounds in milk and cheese.

    PubMed

    Valdivielso, I; Bustamante, M A; Aldezabal, A; Amores, G; Virto, M; Ruiz de Gordoa, J C; de Renobales, M; Barron, L J R

    2016-04-15

    Terpenoid, fat-soluble antioxidant and fatty acid (FA) composition of pasture as well as those of milk and cheese from a commercial sheep flock managed under extensive mountain grazing in the east region of the Cantabrian mountain (Northern Spain) was investigated. The grazing period lasted for 2 months and ewes were at late lactation stage. Plants, feces, bulk milk and cheese samples were collected on two sampling dates. The abundance of the dominating botanical families in the mountain pasture prevailed in the sheep diet of the commercial flock. Major terpenoids and tocols in the pasture appeared as major ones in milk and cheese, whereas C18 unsaturated FAs in milk and cheese were derived from the intake of C18 polyunsaturated FAs which were prevalent in the pasture. No carotene was detected in the dairy samples but retinol (free or esterified), derived from the intake of β-carotene present in pasture plants, was found in milk and cheese.

  19. Combining multi-spectral proximal sensors and digital cameras for monitoring grazed tropical pastures

    NASA Astrophysics Data System (ADS)

    Handcock, R. N.; Gobbett, D. L.; González, L. A.; Bishop-Hurley, G. J.; McGavin, S. L.

    2015-11-01

    Timely and accurate monitoring of pasture biomass and ground-cover is necessary in livestock production systems to ensure productive and sustainable management of forage for livestock. Interest in the use of proximal sensors for monitoring pasture status in grazing systems has increased, since such sensors can return data in near real-time, and have the potential to be deployed on large properties where remote sensing may not be suitable due to issues such as spatial scale or cloud cover. However, there are unresolved challenges in developing calibrations to convert raw sensor data to quantitative biophysical values, such as pasture biomass or vegetation ground-cover, to allow meaningful interpretation of sensor data by livestock producers. We assessed the use of multiple proximal sensors for monitoring tropical pastures with a pilot deployment of sensors at two sites on Lansdown Research Station near Townsville, Australia. Each site was monitored by a Skye SKR-four-band multi-spectral sensor (every 1 min), a digital camera (every 30 min), and a soil moisture sensor (every 1 min), each operated over 18 months. Raw data from each sensor were processed to calculate a number of multispectral vegetation indices. Visual observations of pasture characteristics, including above-ground standing biomass and ground cover, were made every 2 weeks. A methodology was developed to manage the sensor deployment and the quality control of the data collected. The data capture from the digital cameras was more reliable than the multi-spectral sensors, which had up to 63 % of data discarded after data cleaning and quality control. We found a strong relationship between sensor and pasture measurements during the wet season period of maximum pasture growth (January to April), especially when data from the multi-spectral sensors were combined with weather data. RatioNS34 (a simple band ratio between the near infrared (NIR) and lower shortwave infrared (SWIR) bands) and rainfall since 1

  20. Grazing management effects on sediment, phosphorus, and pathogen loading of streams in cool-season grass pastures.

    PubMed

    Schwarte, Kirk A; Russell, James R; Kovar, John L; Morrical, Daniel G; Ensley, Steven M; Yoon, Kyoung-Jin; Cornick, Nancy A; Cho, Yong Il

    2011-01-01

    Erosion and runoff from pastures may lead to degradation of surface water. A 2-yr grazing study was conducted to quantify the effects of grazing management on sediment, phosphorus (P), and pathogen loading of streams in cool-season grass pastures. Six adjoining 12.1-ha pastures bisected by a stream in central Iowa were divided into three treatments: continuous stocking with unrestricted stream access (CSU), continuous stocking with restricted stream access (CSR), and rotational stocking (RS). Rainfall simulations on stream banks resulted in greater ( < 0.10) proportions of applied precipitation and amounts of sediment and P transported in runoff from bare sites than from vegetated sites across grazing treatments. Similar differences were observed comparing vegetated sites in CSU and RS pastures with vegetated sites in CSR pastures. Bovine enterovirus was shed by an average of 24.3% of cows during the study period and was collected in the runoff of 8.3 and 16.7% of runoff simulations on bare sites in CSU pastures in June and October of 2008, respectively, and from 8.3% of runoff simulations on vegetated sites in CSU pastures in April 2009. Fecal pathogens (bovine coronavirus [BCV], bovine rotavirus group A, and O157:H7) shed or detected in runoff were almost nonexistent; only BCV was detected in feces of one cow in August of 2008. Erosion of cut-banks was the greatest contributor of sediment and P loading to the stream; contributions from surface runoff and grazing animals were considerably less and were minimized by grazing management practices that reduced congregation of cattle by pasture streams.

  1. Mountain pastures of Qilian Shan: plant communities, grazing impact and degradation status (Gansu province, NW China)

    NASA Astrophysics Data System (ADS)

    Baranova, Alina; Schickhoff, Udo; Shunli, Wang; Ming, Jin

    2015-04-01

    Qilian Mountains are the water source region for the low arid reaches of HeiHe river basin (Gansu province, NW China). Due to overstocking and overgrazing during the last decades adverse ecological ef¬fects, in particular on soil properties and hydrological cycle, are to be expected in growing land areas. Vegetation cover is very important to prevent erosion process and to sustain stable subsurface runoff and ground water flow. The aim of this research is to identify plant communities, detecting grazing-induced and spatially differentiated changes in vegetation patterns, and to evaluate status of pasture land degradation.The study area is located in the spring/autumn pasture area of South Qilian Mountains between 2600-3600 m a.s.l., covering five main vegetation types: spruce forest, alpine shrubland, shrubby grassland, mountain grassland, degraded mountain grassland. In order to analyze gradual changes in vegetation patterns along altitudinal and grazing gradients and to classify related plant communities, quantitative and qualitative relevé data were collected (coverage, species composition, abundance of unpalatable plants, plant functional types, etc.). Vegetation was classified using hierarchical cluster analyses. Indirect Detrended Correspondence Analysis (DCA) was used to analyze variation in relationships between vegetation, environmental factors, and grazing impact. According to DCA results, distribution of the plant communities was strongly affected by altitude and exposition. Grassland floristic gradients showed greater dependence on grazing impact, which correlated contrarily with soil organic content, soil moisture and pH. Highest numbers of species richness and alpha diversity were detected in alpine shrubland vegetation type. Comparing the monitoring data for the recent nine years, a trend of deterioration, species successions and shift in dominant species becomes obvious. Species indicating degrading site environmental conditions were identified

  2. Performance of Angus and Brangus cow-calf pairs grazing Alicia bermudagrass and common bermudagrass-dallisgrass pastures.

    PubMed

    Wyatt, W E; Gates, R N; Blouin, D C; Saxton, A M; Nelson, B D

    1997-07-01

    This research was designed to examine genotype x environment interactions in cow-calf growth performance of grazing animals. Angus and Brangus cow-calf pairs (minimum of six per breed) were allowed to rotationally graze (14-d intervals) treatment pastures from approximately May through early October in each of 2 yr. Treatment pastures contained relatively pure stands of Alicia bermudagrass (AP) or a mixed stand of common bermudagrass and dallisgrass (CDP). Forage allowance was equalized, using "put-and-take" cow-calf pairs, among forage and breed types at the initiation of each 14-d grazing interval. Forage samples were obtained in each paddock at the initiation of each grazing interval. Forage CP concentration was greater (P < .05; 13.5 vs 11.6%) and NDF concentration was less (P < .05; 63.8 vs 70.6%) for CDP than for AP. Daily weight loss was similar for Angus and Brangus cows, but it was greater (P < .05) for cows grazing AP than for cows grazing CDP. Calf ADG during the grazing season was 35% greater (P < .05) for CDP than for AP pastures and was 23% greater (P < .01) for Brangus than for Angus calves. Relative performance of Angus and Brangus cow-calf pairs was consistent between forages; no breed x forage interactions were observed.

  3. Performance of Angus and Brangus cow-calf pairs grazing Alicia bermudagrass and common bermudagrass-dallisgrass pastures.

    PubMed

    Wyatt, W E; Gates, R N; Blouin, D C; Saxton, A M; Nelson, B D

    1997-07-01

    This research was designed to examine genotype x environment interactions in cow-calf growth performance of grazing animals. Angus and Brangus cow-calf pairs (minimum of six per breed) were allowed to rotationally graze (14-d intervals) treatment pastures from approximately May through early October in each of 2 yr. Treatment pastures contained relatively pure stands of Alicia bermudagrass (AP) or a mixed stand of common bermudagrass and dallisgrass (CDP). Forage allowance was equalized, using "put-and-take" cow-calf pairs, among forage and breed types at the initiation of each 14-d grazing interval. Forage samples were obtained in each paddock at the initiation of each grazing interval. Forage CP concentration was greater (P < .05; 13.5 vs 11.6%) and NDF concentration was less (P < .05; 63.8 vs 70.6%) for CDP than for AP. Daily weight loss was similar for Angus and Brangus cows, but it was greater (P < .05) for cows grazing AP than for cows grazing CDP. Calf ADG during the grazing season was 35% greater (P < .05) for CDP than for AP pastures and was 23% greater (P < .01) for Brangus than for Angus calves. Relative performance of Angus and Brangus cow-calf pairs was consistent between forages; no breed x forage interactions were observed. PMID:9222851

  4. Methane Emission and Milk Production of Dairy Cows Grazing Pastures Rich in Legumes or Rich in Grasses in Uruguay

    PubMed Central

    Dini, Yoana; Gere, José; Briano, Carolina; Manetti, Martin; Juliarena, Paula; Picasso, Valentin; Gratton, Roberto; Astigarraga, Laura

    2012-01-01

    Simple Summary GHGs emissions are relevant in evaluating environmental impact of farming systems. Methane (CH4) produced by enteric fermentation accounts for half of all anthropogenic emissions of GHGs in Uruguay, where ruminant production is based on year round grazing of forages. Here we compared milk production and CH4 emissions by dairy cows grazing two contrasting mixed pastures (rich in legumes or rich in grasses) using the SF6 tracer technique adapted to collect breath samples over 5-days periods. There were no differences in milk or CH4 production between the contrasting pastures, probably because of the high herbage allowance that enabled selective grazing by cows. Abstract Understanding the impact of changing pasture composition on reducing emissions of GHGs in dairy grazing systems is an important issue to mitigate climate change. The aim of this study was to estimate daily CH4 emissions of dairy cows grazing two mixed pastures with contrasting composition of grasses and legumes: L pasture with 60% legumes on Dry Matter (DM) basis and G pasture with 75% grasses on DM basis. Milk production and CH4 emissions were compared over two periods of two weeks during spring using eight lactating Holstein cows in a 2 × 2 Latin square design. Herbage organic matter intake (HOMI) was estimated by chromic oxide dilution and herbage organic matter digestibility (OMD) was estimated by faecal index. Methane emission was estimated by using the sulfur hexafluoride (SF6) tracer technique adapted to collect breath samples over 5-day periods. OMD (0.71) and HOMI (15.7 kg OM) were not affected by pasture composition. Milk production (20.3 kg/d), milk fat yield (742 g/d) and milk protein yield (667 g/d) were similar for both pastures. This may be explained by the high herbage allowance (30 kg DM above 5 cm/cow) which allowed the cows to graze selectively, in particular in grass sward. Similarly, methane emission expressed as absolute value (368 g/d or 516 L/d) or expressed as

  5. Adjusting homestead feeding to requirements and nutrient intake of grazing goats on semi-arid, subtropical highland pastures.

    PubMed

    Dickhoefer, U; Mahgoub, O; Schlecht, E

    2011-03-01

    Intensive livestock grazing can largely deplete the natural fodder resources in semi-arid, subtropical highlands and together with the low nutritional quality of the pasture vegetation limit the growth and production of grazing animals. To evaluate the contribution of homestead feeding of grazing goats to rangeland conservation and animal nutrition, two researcher-managed on-farm trials were conducted in a mountain oasis of Northern Oman. Goats' feed intake on pasture in response to four rations containing different levels of locally available green fodder and concentrate feeds was determined in six male goats each (35 ± 10.2 kg body weight (BW)). Total feed intake was estimated using titanium dioxide as external fecal marker as well as the diet organic matter (OM) digestibility derived from fecal crude protein concentration. The nutritional quality of selected fodder plants on pasture was analyzed to determine the animals' nutrient and energy intake during grazing. The pasture vegetation accounted for 0.46 to 0.65 of the goats' total OM intake (87 to 107 g/kg0.75 BW), underlining the importance of this fodder resource for the husbandry system. However, metabolizable energy (7.2 MJ/kg OM) and phosphorus concentrations (1.4 g/kg OM) in the consumed pasture plants were low. Homestead feeding of nutrient and energy-rich by-products of the national fishery and date palm cultivation to grazing goats increased their daily OM intake (R2 = 0.36; P = 0.005) and covered their requirements for growth and production. While the OM intake on pasture was highest in animals fed a concentrate-based diet (P = 0.003), the daily intake of 21 g OM/kg0.75 BW of cultivated green fodder reduced the animals' feed intake on pasture (R2 = 0.44; P = 0.001). Adjusting homestead supplementation with locally available feedstuffs to the requirements of individual goats and to the nutritional quality of the pasture vegetation improves animal performance and eases the grazing pressure exerted on

  6. Adjusting homestead feeding to requirements and nutrient intake of grazing goats on semi-arid, subtropical highland pastures.

    PubMed

    Dickhoefer, U; Mahgoub, O; Schlecht, E

    2011-03-01

    Intensive livestock grazing can largely deplete the natural fodder resources in semi-arid, subtropical highlands and together with the low nutritional quality of the pasture vegetation limit the growth and production of grazing animals. To evaluate the contribution of homestead feeding of grazing goats to rangeland conservation and animal nutrition, two researcher-managed on-farm trials were conducted in a mountain oasis of Northern Oman. Goats' feed intake on pasture in response to four rations containing different levels of locally available green fodder and concentrate feeds was determined in six male goats each (35 ± 10.2 kg body weight (BW)). Total feed intake was estimated using titanium dioxide as external fecal marker as well as the diet organic matter (OM) digestibility derived from fecal crude protein concentration. The nutritional quality of selected fodder plants on pasture was analyzed to determine the animals' nutrient and energy intake during grazing. The pasture vegetation accounted for 0.46 to 0.65 of the goats' total OM intake (87 to 107 g/kg0.75 BW), underlining the importance of this fodder resource for the husbandry system. However, metabolizable energy (7.2 MJ/kg OM) and phosphorus concentrations (1.4 g/kg OM) in the consumed pasture plants were low. Homestead feeding of nutrient and energy-rich by-products of the national fishery and date palm cultivation to grazing goats increased their daily OM intake (R2 = 0.36; P = 0.005) and covered their requirements for growth and production. While the OM intake on pasture was highest in animals fed a concentrate-based diet (P = 0.003), the daily intake of 21 g OM/kg0.75 BW of cultivated green fodder reduced the animals' feed intake on pasture (R2 = 0.44; P = 0.001). Adjusting homestead supplementation with locally available feedstuffs to the requirements of individual goats and to the nutritional quality of the pasture vegetation improves animal performance and eases the grazing pressure exerted on

  7. Methane Emission and Milk Production of Dairy Cows Grazing Pastures Rich in Legumes or Rich in Grasses in Uruguay.

    PubMed

    Dini, Yoana; Gere, José; Briano, Carolina; Manetti, Martin; Juliarena, Paula; Picasso, Valentin; Gratton, Roberto; Astigarraga, Laura

    2012-01-01

    Understanding the impact of changing pasture composition on reducing emissions of GHGs in dairy grazing systems is an important issue to mitigate climate change. The aim of this study was to estimate daily CH₄ emissions of dairy cows grazing two mixed pastures with contrasting composition of grasses and legumes: L pasture with 60% legumes on Dry Matter (DM) basis and G pasture with 75% grasses on DM basis. Milk production and CH₄ emissions were compared over two periods of two weeks during spring using eight lactating Holstein cows in a 2 × 2 Latin square design. Herbage organic matter intake (HOMI) was estimated by chromic oxide dilution and herbage organic matter digestibility (OMD) was estimated by faecal index. Methane emission was estimated by using the sulfur hexafluoride (SF6) tracer technique adapted to collect breath samples over 5-day periods. OMD (0.71) and HOMI (15.7 kg OM) were not affected by pasture composition. Milk production (20.3 kg/d), milk fat yield (742 g/d) and milk protein yield (667 g/d) were similar for both pastures. This may be explained by the high herbage allowance (30 kg DM above 5 cm/cow) which allowed the cows to graze selectively, in particular in grass sward. Similarly, methane emission expressed as absolute value (368 g/d or 516 L/d) or expressed as methane yield (6.6% of Gross Energy Intake (GEI)) was not affected by treatments. In conclusion, at high herbage allowance, the quality of the diet selected by grazing cows did not differ between pastures rich in legumes or rich in grasses, and therefore there was no effect on milk or methane production. PMID:26486922

  8. Volatile compounds and sensory properties of Montasio cheese made from the milk of Simmental cows grazing on alpine pastures.

    PubMed

    Bovolenta, S; Romanzin, A; Corazzin, M; Spanghero, M; Aprea, E; Gasperi, F; Piasentier, E

    2014-12-01

    The aim of this study was to analyze the volatile compounds, physicochemical characteristics, and sensory properties of Montasio, a semicooked pressed cheese, produced from the milk of the dual-purpose Italian Simmental cows grazing on alpine pastures. A total of 72 cows grazing on 2 pastures, which differed in botanical composition (nutrient-rich pasture vs. nutrient-poor pasture), received 2 different levels of supplementation (3.0 vs 1.5 kg/head per day). The experimental cheeses were produced from whole, raw milk and ripened for 60 d. Sixty-one volatile compounds, including alcohols (11), aldehydes (6), ketones (10), lactones (2), esters (6), hydrocarbons (3), carboxylic acids (6), phenolic compounds (4), monoterpenes (7), sesquiterpenes (1), sulfur compounds (4), and amines (1), were detected. The main families in terms of relative weight appeared to be carboxylic acids, esters, and alcohols. A panel of trained assessors described the experimental cheeses as having an intense color; small and evenly distributed eyes; an intense odor and flavor of milk-sour, milk, and cow; and a tender and creamy texture. The pasture type affected the volatile fraction, particularly ketones, phenolic compounds, and terpenes, which are overall higher in nutrient-poor pastures. A slight effect on the sensory analyses, in particular the effect of the cow attribute on odor and flavor, was perceived by the panelists. The cheeses produced on nutrient-rich pasture had higher b* (yellowness) index. These results were consistent with the color evaluation of the sensory panel. In addition, the pasture affected some textural attributes (adhesivity, creaminess, and granules) as perceived by the panelists. Concentrate supplementation, which is required to meet the feeding requirements of grazing cows, had no clear effect on either the volatile compounds or the sensory properties of the cheeses. Thus, at least within levels of integration adopted, it is expected not to alter the organoleptic

  9. Time of daily supplementation for steers grazing dormant intermediate wheatgrass pasture.

    PubMed

    Barton, R K; Krysl, L J; Judkins, M B; Holcombe, D W; Broesder, J T; Gunter, S A; Beam, S W

    1992-02-01

    To compare the effects of time of daily protein supplementation on grazing behavior, forage intake, digesta kinetics, ruminal fermentation, and serum hormones and metabolites, 12 ruminally cannulated Holstein steers (449 and 378 kg average initial and final BW, respectively) were allotted to three groups. Treatments consisted of CON = no supplement, AM = cottonseed meal (.25% of BW) at 0600, and PM = cottonseed meal (.25% of BW) at 1200. Steers grazed a dormant (1.1% N) intermediate wheatgrass (Thinopyrum intermedium Host) pasture. Sampling trials occurred in December, January, and February. Supplementation altered (P = .01) time spent grazing; CON steers grazed approximately 1.5 h longer than supplemented steers. Supplemented steers lost less (P = .02) BW (-40 kg) than CON steers (-75 kg) did. Supplementation did not alter (P greater than .15) forage OM intake; however, total OM intake was greater (P = .01) for supplemented steers (22.3 g/kg of BW) than for CON (18.4 g/kg of BW) steers. Supplementation did not affect (P greater than .15) digesta kinetics. Extent of in situ NDF (96 h) and rate (%/h) of disappearance for supplemented steers was greater (P = .01) than for CON steers. Across all periods, ruminal NH3 N and total VFA concentrations were lower (P = .01) for CON steers than for supplemented steers. Serum insulin (ng/mL) concentration was lower (P = .03) and concentration of serum growth hormone (ng/mL) was higher (P = .02) for CON steers than for supplemented steers. Cottonseed meal supplementation enhanced utilization of intermediate wheatgrass; however, supplementation time had minimal effects on the variables measured.

  10. Relative impacts of land-use, management intensity and fertilization on microbial community structure in agricultural systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Effects of agricultural land management practices on soil prokaryotic diversity have not been well described. Soil microbial communities under three agricultural management systems (conventionally tilled cropland, hayed pasture, and grazed pasture) and two fertilizer systems [inorganic fertilizer (I...

  11. CO2 and Carbon Balance of an Intensively Grazed Temperate Pasture: Response to Cultivation

    NASA Astrophysics Data System (ADS)

    Rutledge, S.; Mudge, P. L.; Wallace, D.; Campbell, D.; Wall, A.; Hosking, C. L.; Schipper, L. A.

    2012-12-01

    Recent soil resampling studies have shown that soils on flat land used for intensive dairy farming in New Zealand have lost large amounts of carbon (~1 t C ha-1y-1) over the past few decades, and the causes of these losses are poorly understood. One of the management practices potentially contributing to the C losses from these dairy soils is the periodic cultivation commonly associated with pasture renewal or the rotation through summer or winter crops. Here we report the results of three experiments aimed at quantifying the effect of cultivation as part of pasture renewal on the CO2 and C balances of permanent pastures. In the first experiment, the net ecosystem CO2 exchange (NEE) of an intensively grazed dairy pasture was measured before, during and after cultivation using eddy covariance (EC) from 2008 to 2011 at a dairy farm in the Waikato region on the North Island of New Zealand. The net ecosystem carbon balance (NECB) was determined by combining NEE data with measurements and estimates of other C imports (feed) and C exports (milk, methane, silage and leaching). The other two experiments took place on the same farm and monitored two different cultivation events in 2008. We made chamber measurements of soil CO2 losses between spraying and seedling emergence. One of the cultivations took place in summer 2008 during a drought, whereas the other took place in spring 2008 when soil water was not limiting. For the first two years of experiment 1 the site was under permanent pasture and it was a sink for both CO2 (1.6 and 2.3 t C ha-1y-1 for 2008 and 2009, respectively) and C (0.59 and 0.90 t C ha-1y-1 for 2008 and 2009, respectively), despite a severe drought in summer 2008 which had led to a loss of approximately 1.1 t C ha-1 as CO2 over the three summer months. Pasture renewal took place in March 2010 and CO2 losses during this event were approximately 1.7 t C ha-1. However, the site seemed to recover quickly and was a sink of CO2 at an annual time scale of

  12. Soil-extractable phosphorus and phosphorus saturation threshold in beef cattle pastures as affected by grazing management and forage type.

    PubMed

    Sigua, Gilbert C; Chase, Chad C; Albano, Joseph

    2014-02-01

    Grazing can accelerate and alter the timing of nutrient transfer, and could increase the amount of extractable phosphorus (P) cycle from soils to plants. The effects of grazing management and/or forage type that control P cycling and distribution in pasture's resources have not been sufficiently evaluated. Our ability to estimate the levels and changes of soil-extractable P and other crop nutrients in subtropical beef cattle pastures has the potential to improve our understanding of P dynamics and nutrient cycling at the landscape level. To date, very little attention has been paid to evaluating transfers of extractable P in pasture with varying grazing management and different forage type. Whether or not P losses from grazed pastures are significantly greater than background losses and how these losses are affected by soil, forage management, or stocking density are not well understood. The objective of this study was to evaluate the effect of grazing management (rotational versus "zero" grazing) and forage types (FT; bahiagrass, Paspalum notatum, Flugge versus rhizoma peanuts, Arachis glabrata, Benth) on the levels of extractable soil P and degree of P saturation in beef cattle pastures. This study (2004-2007) was conducted at the Subtropical Agricultural Research Station, US Department of Agriculture-Agricultural Research Service located 7 miles north of Brooksville, FL. Soil (Candler fine sand) at this location was described as well-drained hyperthermic uncoated Typic Quartzipsamments. A split plot arrangement in a completely randomized block design was used and each treatment was replicated four times. The main plot was represented by grazing management (grazing vs. no grazing) while forage types (bahiagrass vs. perennial peanut) as the sub-plot treatment. Eight steel exclosures (10 × 10 m) were used in the study. Four exclosures were placed and established in four pastures with bahiagrass and four exclosures were established in four pastures with rhizoma

  13. Diet quality and ruminal digestion in beef cattle grazing midgrass prairie rangeland or plains bluestem pasture throughout the summer.

    PubMed

    Gunter, S A; McCollum, F T; Gillen, R L; Krysl, L J

    1995-04-01

    Beef cattle fitted with esophageal (four steers/pasture) or ruminal and duodenal (six calves/pasture; beginning BW +/- SE = 267 +/- 6 kg) cannulas grazed midgrass prairie rangeland (excellent range condition; MIDGRASS) or plains bluestem (Bothriochloa ischaemum var. Plains) pasture (BLUESTEM) in mid-May, late-June, mid-August, and mid-October of 1990 and 1991. Nitrogen in masticate samples collected from MIDGRASS was lowest (P < .05) in June and August across both years. The N in BLUESTEM masticate peaked (P < .05) in August 1990, but N was lowest (P < .05) in August 1991. The detergent fiber content of masticate from both forages increased (P < .05) as the grazing season advanced from May through August; fall regrowth in October occasionally resulted in a small decrease (P < .05) in fiber content. In vitro OM disappearance (IVOMD) followed a pattern similar to N content. The IVOMD of BLUESTEM masticate was greater (P < .05) than that of MIDGRASS masticate. The ruminal ammonia N concentration (milligrams/deciliter) in cattle grazing BLUESTEM (4.5) usually was greater (P < .05) than in cattle grazing MIDGRASS (3.3). In situ OM and N disappearance was greater (P < .05) from BLUESTEM masticate than from MIDGRASS masticate in May, June, and August. The ruminally degraded N:ruminally degraded OM ratio (grams/kilograms) estimated from in situ digestion suggested that cattle grazing MIDGRASS during the mid-summer of both years and BLUESTEM in August 1991 may have been marginally deficient in ruminally degraded N. Plains bluestem pasture would complement MIDGRASS by providing better quality grazing during the mid-summer.

  14. Changes in soil carbon cycling accompanying conversion of row-crop fields to grazing dairy pastures

    NASA Astrophysics Data System (ADS)

    Thompson, A.; Kramer, M. G.; Hill, N.; Machmuller, M. B.; Cyle, K.

    2011-12-01

    Increasingly, the dairy industry in the eastern US is transitioning from total confinement dairy systems (TCD) toward pasture-based, management intensive grazing dairy (MiGD) systems. This transition is driven by the fact that MiGDs require substantially less operating capital and are more economically efficient than TCD systems. Consequently, the impact of this transition and shift in land-use practice on carbon dynamics may be considerable. Land-use in a Management intensive Grazing Dairy (MiGD) system is fundamentally different than conventional confinement dairies and conventional no-till pastures. The forage system involves rotational grazing at optimal digestibility, when the plants are immature (~20-days) and consequently protein-rich. MiGD cows spend >90% of their time in the field and deposit > 90% of their waste directly to the soil surface. Thus, little above ground plant residues are directly returned to the soil, but rather substantial C inputs derive from bovine manure. We sampled a MiGD-chronosequence of row-crop to MiGD conversion established in 2007 in eastern Georgia. All soils across the MiGD-chronosequence, all occur in relative (40 km) close proximity to one another, are deep, well-drained, fine and fine sandy loam Ultisols formed on Coastal Plain sediments. Prior to MiGD established, the soils were farmed for > 50 yrs using conventional tillage techniques. Our current sampling to 1m depths captures fields at 0, 2, 3, and 5 yrs since conversion. Total soil carbon (C) and the carbon concentration of the clay fraction increased following conversion, with the greatest increases occurring between 3 and 5 yrs since conversion. These C increases were limited to the upper 40cm of the soil, with minimal change occurring at depth. Characterization of the protein and ligand content of these soils via 13C NMR and chemolytic techniques as a function of soil particle density and size is in progress and will be presented along with estimates of carbon

  15. Leaf economics spectrum-productivity relationships in intensively grazed pastures depend on dominant species identity.

    PubMed

    Mason, Norman W H; Orwin, Kate; Lambie, Suzanne; Woodward, Sharon L; McCready, Tiffany; Mudge, Paul

    2016-05-01

    Plant functional traits are thought to drive variation in primary productivity. However, there is a lack of work examining how dominant species identity affects trait-productivity relationships. The productivity of 12 pasture mixtures was determined in a 3-year field experiment. The mixtures were based on either the winter-active ryegrass (Lolium perenne) or winter-dormant tall fescue (Festuca arundinacea). Different mixtures were obtained by adding forb, legume, and grass species that differ in key leaf economics spectrum (LES) traits to the basic two-species dominant grass-white clover (Trifolium repens) mixtures. We tested for correlations between community-weighted mean (CWM) trait values, functional diversity, and productivity across all plots and within those based on either ryegrass or tall fescue. The winter-dormant forb species (chicory and plantain) had leaf traits consistent with high relative growth rates both per unit leaf area (high leaf thickness) and per unit leaf dry weight (low leaf dry matter content). Together, the two forb species achieved reasonable abundance when grown with either base grass (means of 36% and 53% of total biomass, respectively, with ryegrass tall fescue), but they competed much more strongly with tall fescue than with ryegrass. Consequently, they had a net negative impact on productivity when grown with tall fescue, and a net positive effect when grown with ryegrass. Strongly significant relationships between productivity and CWM values for LES traits were observed across ryegrass-based mixtures, but not across tall fescue-based mixtures. Functional diversity did not have a significant positive effect on productivity for any of the traits. The results show dominant species identity can strongly modify trait-productivity relationships in intensively grazed pastures. This was due to differences in the intensity of competition between dominant species and additional species, suggesting that resource-use complementarity is a

  16. Effects of supplementing Leucaena leucocephala and conserved forages from natural pasture on the performance of grazing calves.

    PubMed

    Ojo, Victoria Olubunmi A; Aina, Ayobami B J; Fasae, Oladapo A; Oni, Adebayo O; Aderinboye, Ronke Y; Dele, Peter A; Idowu, Oluwaseun J; Adelusi, Oludotun O; Shittu, Olalekan O; Okeniyi, Funmilayo A; Jolaosho, Alaba O

    2014-01-01

    Twelve white Fulani × N'dama cross-bred calves weighing 83.79 ± 1.16 kg were used in an 84-day experiment to investigate the utilization of forage resources from natural grazing land. The experimental diets were sole grazing, grazing + hay, grazing + silage and grazing + Leucaena leucocephala leaves. The calves were divided into four groups of three animals each and were randomly assigned to the four experimental diets. Crude protein (CP) contents of the forages ranged from 59 to 171 g/kg dry matter (DM). Neutral detergent fibre (NDF) and acid detergent fibre (ADF) contents of the forages ranged from 560 to 705 g/kg DM and 363 to 440 g/kg DM, respectively. Significantly (P < 0.05) higher values in mineral contents (Ca, K, P and Mg) were recorded for L. leucocephala leaves compared to other forage resources. Variations (P < 0.05) were observed in the average daily gain. Animals on grazing + L. leucocephala leaves diet had the highest (113 g/day) average daily gain, while those on sole grazing showed the least value (26.2 g/day). Packed cell volume (PCV), total serum protein, urea and calcium concentration showed significant differences (P < 0.05). Effective utilization of forage resources from the natural pasture by the calves was attained on supplementation with conserved forages and L. leucocephala leaves without any deleterious effects on the haematological and serum parameters. PMID:24077958

  17. Fatty acid profile of plasma, muscle and adipose tissues in Chilota lambs grazing on two different low quality pasture types in Chiloé Archipelago (Chile).

    PubMed

    Gallardo, Maria A; Dannenberger, Dirk; Rivero, Jordana; Pulido, Ruben; Nuernberg, Karin

    2014-11-01

    There is no information about the effect of different pasture types on tissue fatty acid profiles of a native rustic lamb breed of the Chiloe Archipelago, the Chilota. Eight Chilota lambs were grazed on a 'Calafatal' pasture (CP), a typical secondary succession of Chiloé Archipelago (Chile) and eight Chilota lambs were located to graze on naturalized pasture (NP) of Chiloé. Botanical, chemical and lipid composition of the two types of pastures and of different lamb tissues (muscle, subcutaneous - and tail adipose tissues) and plasma were performed. Both pasture types induced high n-3 polyunsaturated fatty acids (PUFA) and CLAcis-9,trans-11 proportions in Chilota meat. Thus, in muscle, Chilota lambs grazing CP showed higher sum PUFA, sum n-6 PUFA proportion and n-6/n-3 PUFA ratio compared with Chilota lambs grazing NP. In tail fats of Chilota lambs grazing CP significantly higher proportions of 18:3n-3, sum saturated fatty acids, sum PUFA, n-3 and n-6 PUFA were detected compared with Chilota lambs grazing NP. Feeding of different pasture types (CP vs. NP) caused significant differences in fatty acid composition of muscle and the two fat depots in Chilota lambs, but also point to tissue-specific responses of de novo synthesized fatty acid deposition in the tissues.

  18. Growth performances of F1 Angus Plus calves grazing on pasture in Hawaii's tropical climate.

    PubMed

    Yang, J; Ferreira, R; Duponte, M W; Fukumoto, G K; Zhao, B

    2009-04-01

    Angus Plus cattle offer advantages for heat tolerance and forage utilization by introduction of Brangus and Brahman to Angus. To evaluate its adaptability in Hawaii Islands, we reported the growth performances of 213 F1 Angus Plus calve grazing on pasture. Least-square means of pre-weaning ADG ranged from 1,087 to 1,167 g in bull calves and from 1,030 to 1,048 g in heifer calves. The 205 d-adjusted weaning weight were 226 to 285 kg in bulls and 214 to 252 kg in heifers. The birth weight and hip height at birth were significantly correlated with weaning weight, 205 d-adjusted weaning weight, hip height at weaning and pre-weaning ADG (P < 0.01). Sire group significantly influenced pre-weaning growth performances through interaction with sex of calf. Bull calves from sire group of high growth were 1.0-3.8 kg heavier in birth weight than the bull calves from other sires (P < 0.001). Sire group x sex interaction was significant (P < 0.05) for calf birth weight, 205-d adjusted weaning weight and pre-weaning ADG. Sire group also played a significant role in hip height at birth (P < 0.05). Selections of the sires preferable for growth significantly improved calf pre-weaning growth performances. PMID:18759132

  19. Trace gas responses of tropical forest and pasture soils to N and P fertilization

    NASA Astrophysics Data System (ADS)

    Steudler, Paul A.; Garcia-Montiel, Diana C.; Piccolo, Marisa C.; Neill, Christopher; Melillo, Jerry M.; Feigl, Brigitte J.; Cerri, Carlos C.

    2002-05-01

    We measured the responses of nitric oxide (NO), nitrous oxide (N2O) and carbon dioxide (CO2) to nitrogen (N) and/or phosphorus (P) fertilization in a mature moist tropical forest and an 11-year-old pasture in the Brazilian Amazon. Nitrogen was applied in two forms, ammonium (NH4+) and nitrate (NO3-). In the forest, NO emissions increased by 4 to 9 times the controls in the NH4+ amended plots. Nitrous oxide emissions showed a small response only in the NH4+ amended plots. In the pasture, NO emissions during the first 7 days after fertilization with either form of N were about twice those in the control plots. Nitrous oxide emissions increased more than 18 times the controls in the NO3- amended plots 1 day after fertilization. The estimated yields of total nitrogen oxide loss from the forest were between 0.2 and 1.6% of the applied nitrogen, predominately as NO. Pasture yields were greater, up to 2.8% of the applied nitrogen, predominately as N2O. In the context of Rondônia and other regions in the Amazon Basin, pasture management practices are changing to include increased use of fertilizer, particularly in older pastures that have lower NO and N2O emissions than the original intact forests. This may lead to large short-term releases of N2O and alter the future N2O emissions from the Basin.

  20. Trace gas responses of tropical forest and pasture soils to N and P fertilization

    NASA Astrophysics Data System (ADS)

    Steudler, Paul A.; Garcia-Montiel, Diana C.; Piccolo, Marisa C.; Neill, Christopher; Melillo, Jerry M.; Feigl, Brigitte J.; Cerri, Carlos C.

    2002-06-01

    We measured the responses of nitric oxide (NO), nitrous oxide (N2O) and carbon dioxide (CO2) to nitrogen (N) and/or phosphorus (P) fertilization in a mature moist tropical forest and an 11-year-old pasture in the Brazilian Amazon. Nitrogen was applied in two forms, ammonium (NH4+) and nitrate (NO3-). In the forest, NO emissions increased by 4 to 9 times the controls in the NH4+ amended plots. Nitrous oxide emissions showed a small response only in the NH4+ amended plots. In the pasture, NO emissions during the first 7 days after fertilization with either form of N were about twice those in the control plots. Nitrous oxide emissions increased more than 18 times the controls in the NO3- amended plots 1 day after fertilization. The estimated yields of total nitrogen oxide loss from the forest were between 0.2 and 1.6% of the applied nitrogen, predominately as NO. Pasture yields were greater, up to 2.8% of the applied nitrogen, predominately as N2O. In the context of Rondônia and other regions in the Amazon Basin, pasture management practices are changing to include increased use of fertilizer, particularly in older pastures that have lower NO and N2O emissions than the original intact forests. This may lead to large short-term releases of N2O and alter the future N2O emissions from the Basin.

  1. Effects of different strategies for feeding supplements on milk production responses in cows grazing a restricted pasture allowance.

    PubMed

    Auldist, M J; Marett, L C; Greenwood, J S; Hannah, M; Jacobs, J L; Wales, W J

    2013-02-01

    Milk production responses of grazing cows offered supplements in different ways were measured. Holstein-Friesian cows, averaging 227 d in milk, were allocated into 6 groups of 36, with 2 groups randomly assigned to each of 3 feeding strategies: (1) cows grazed perennial ryegrass pasture supplemented with milled barley grain fed in the milking parlor and pasture silage offered in the paddock (control); (2) same pasture and allotment supplemented with the same amounts of milled barley grain and pasture silage, but presented as a mixed ration after each milking (PMR 1); and (3) same pasture and allotment, supplemented with a mixed ration of milled barley grain, alfalfa hay, corn silage, and crushed corn grain (PMR 2). For all strategies, supplements provided the same metabolizable energy and grain:forage ratio. [75:25, dry matter (DM) basis]. Each group of 36 cows was further allocated into 4 groups of 9, which were assigned to receive 6, 8, 10, or 12 kg of supplement DM/cow per day. Thus, there were 2 replicated groups per supplement amount per dietary strategy. The experiment had a 14-d adaptation period and an 11-d measurement period. Pasture allotment was approximately 14 kg of DM/d for all cows and was offered in addition to the supplement. Positive quadratic responses to increasing amounts of supplement were observed for yield of milk, energy-corrected milk (ECM), and fat and protein, and positive linear responses for concentrations of fat and protein for cows on all 3 supplement feeding strategies. No difference existed between feeding strategy groups in yield of milk, ECM, or protein at any amount of supplement offered, but yield and concentration of fat was higher in PMR 2 cows compared with control and PMR 1 cows at the highest amounts of supplementation. Responses in marginal ECM production per additional kilogram of supplement were also greater for PMR 2 than control and PMR 1 cows when large amounts of supplement were consumed. For all diets, marked daily

  2. Management effects on the distribution of soil characteristics of two pasture types in Oklahoma

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pastures of native prairie and winter wheat are among the primary resources used to graze cattle in central Oklahoma. These pastures are subject to numerous stressors that affect land condition including grazing, climate, soil fertility, and farming operations. Understanding responses of soil charac...

  3. Achieving model-data harmony by viewing C and N isotopes through the same window: grazed pasture irrigation treatments over 42 years in New Zealand

    NASA Astrophysics Data System (ADS)

    Baisden, T. W.; Schipper, L. A.; Sanderman, J.; Keller, E. D.; Mudge, P. L.; Dodd, M. B.

    2013-12-01

    Carbon (C) and nitrogen (N) form the skeleton of soil organic matter, and are central to the interaction of land use and global change. Both the C and N cycles are considered to be complex, but are often treated in somewhat different ways - particularly in simple models. Thus, highly simplified models often lack consistency with complex data, while models containing many details are often criticized for being poorly constrained. Viewing C and N with a moderate level of complexity appears to offer a promising opportunity to delivery more harmonious interpretations, enabling improved model-data consistency. In grazed pasture trials operated at Winchmore in Canterbury, New Zealand (43°S) we overlay a 12-point Δ14C dataset on recently published records of total C, N and δ15N. The record obtained from archived, replicated samples spans the period from 1959-2002, and compares dryland pasture with pastures irrigated when soil moisture reaches 10% and 20%. The C and N concentrations increased in all treatments, and show that the 20% irrigation treatment stored less C and N compared to the 10% and dryland treatments. The δ15N increases in the treatments followed the pattern: 20%>10%>dryland. The lower storage of C and N under higher levels of irrigation at a site with a long-term record of pasture productivity provides the ideal opportunity to examine whether decomposition rates have been enhanced by irrigation, or rates of organic matter stabilization have slowed, or both. Using two and three pool models with and without steady-state assumptions, we examine the 12-point Δ14C records, and conclude that a decline in the amount of organic matter stabilized under high levels of irrigation is the most likely reason for the treatment comparison. This conclusion is compatible with higher δ15N values in the 20% irrigation treatment reflecting more complete microbial decomposition processes operating in the soil. Noting that irrigation is an adaptive response to climate

  4. Bartonella chomelii is the most frequent species infecting cattle grazing in communal mountain pastures in Spain.

    PubMed

    Antequera-Gómez, M L; Lozano-Almendral, L; Barandika, J F; González-Martín-Niño, R M; Rodríguez-Moreno, I; García-Pérez, A L; Gil, H

    2015-01-01

    The presence of Bartonella spp. was investigated in domestic ungulates grazing in communal pastures from a mountain area in northern Spain, where 18.3% (17/93) of cattle were found to be positive by PCR combined with a reverse line blot (PCR/RLB), whereas sheep (n = 133) or horses (n = 91) were found not to be infected by this pathogen. Bartonella infection was significantly associated with age, since older animals showed a higher prevalence than heifers and calves. In contrast to other studies, B. chomelii was the most frequent species found in cattle (14/17), while B. bovis was detected in only three animals. Moreover, 18 B. chomelii isolates and one B. bovis isolate were obtained from nine animals. Afterwards, B. chomelii isolates were characterized by a multilocus sequence typing (MLST) method which was adapted in this study. This method presented a high discrimination power, identifying nine different sequence types (STs). This characterization also showed the presence of different STs simultaneously in the same host and that STs had switched over time in one of the animals. In addition, B. chomelii STs seem to group phylogenetically in two different lineages. The only B. bovis isolate was characterized with a previously described MLST method. This isolate corresponded to a new ST which is located in lineage I, where the B. bovis strains infecting Bos taurus subsp. taurus are grouped. Further studies on the dynamics of Bartonella infection in cattle and the potential ectoparasites involved in the transmission of this microorganism should be performed, improving knowledge about the interaction of Bartonella spp. and domestic ungulates.

  5. Milk from cows grazing on cool-season pastures provides an enhanced profile of bioactive fatty acids compared to those grazed on a monoculture of pearl millet.

    PubMed

    Bainbridge, Melissa L; Egolf, Emily; Barlow, John W; Alvez, Juan P; Roman, Joe; Kraft, Jana

    2017-02-15

    The demand for dairy products from grass-fed cows is driven, in part, by their more desirable fatty acid (FA) profile, containing more n-3 FA and conjugated linoleic acids (CLA) than conventionally produced dairy products. This study investigated the effects of pearl millet (PM) vs. cool-season pasture (CSP) on animal performance and milk FA in a grazing system. Eight Holstein dairy cows were used in a repeated measures design with four-week periods. Forage type had no effect on animal performance (estimated dry matter intake, milk production, fat, or protein). The contents of CLA and n-3 FA in a serving of whole milk (3.25% fat) increased when cows grazed CSP compared to PM. A serving of whole milk from cows grazing PM had a higher content of saturated FA and branched-chain FA. In conclusion, the contents of various bioactive FA were higher in milk fat of cows grazing a CSP compared to PM. PMID:27664694

  6. Pasture size effects on the ability of off-stream water or restricted stream access to alter the spatial/temporal distribution of grazing beef cows.

    PubMed

    Bisinger, J J; Russell, J R; Morrical, D G; Isenhart, T M

    2014-08-01

    For 2 grazing seasons, effects of pasture size, stream access, and off-stream water on cow distribution relative to a stream were evaluated in six 12.1-ha cool-season grass pastures. Two pasture sizes (small [4.0 ha] and large [12.1 ha]) with 3 management treatments (unrestricted stream access without off-stream water [U], unrestricted stream access with off-stream water [UW], and stream access restricted to a stabilized stream crossing [R]) were alternated between pasture sizes every 2 wk for 5 consecutive 4-wk intervals in each grazing season. Small and large pastures were stocked with 5 and 15 August-calving cows from mid May through mid October. At 10-min intervals, cow location was determined with Global Positioning System collars fitted on 2 to 3 cows in each pasture and identified when observed in the stream (0-10 m from the stream) or riparian (0-33 m from the stream) zones and ambient temperature was recorded with on-site weather stations. Over all intervals, cows were observed more (P ≤ 0.01) frequently in the stream and riparian zones of small than large pastures regardless of management treatment. Cows in R pastures had 24 and 8% less (P < 0.01) observations in the stream and riparian zones than U or UW pastures regardless of pasture size. Off-stream water had little effect on the presence of cows in or near pasture streams regardless of pasture size. In 2011, the probability of cow presence in the stream and riparian zones increased at greater (P < 0.04) rates as ambient temperature increased in U and UW pastures than in 2010. As ambient temperature increased, the probability of cow presence in the stream and riparian zones increased at greater (P < 0.01) rates in small than large pastures. Across pasture sizes, the probability of cow presence in the stream and riparian zone increased less (P < 0.01) with increasing ambient temperatures in R than U and UW pastures. Rates of increase in the probability of cow presence in shade (within 10 m of tree

  7. The effect of sustained release boli with ammoniumiron(III)-hexacyanoferrate(II) on radiocesium accumulation in sheep grazing contaminated pasture

    SciTech Connect

    Hansen, H.S.; Hove, K.; Barvik, K.

    1996-11-01

    Sustained release boli with the cesium binder ammoniumiron(III)-hexacyanoferrate(II) (AFCF) were tested under practical conditions for sheep grazing on pastures contaminated with radiocesium ({sup 134}Cs+{sup 137}Cs) from the Chernobyl fallout. Two types of AFCF boli were developed: boli without a protective surface coating intended to last 4-8 wk; and boli coated by a wax-mixture with an extended duration of 10-12 wk. From 1989 to 1993 we measured the effect of wax-coated and uncoated boli administered at various times during the grazing season to a total of 3,248 animals. Reductions in radiocesium levels in meat of sheep were measured by in vivo monitoring. Administration of AFCF boli without a wax-coating reduced the mean radiocesium levels in lambs by 42-75% over a 408 wk period, and administration of the wax-coated AFCF boli reduced the mean radiocesium levels by 48-65% over a 9-11 wk period. The coefficients of variation in meat radiocesium levels were similar in treated and control groups at the end of the observation period, showing that the reduction of meat radiocesium values was homogeneous throughout the treated groups. The boli giving sustained release of AFCF is a labor-saving and cost effective counter-measure for sheep grazing radiocesium contaminated pastures. 16 refs., 4 figs., 4 tabs.

  8. Additive effects of growth promoting technologies on performance of grazing steers and economics of the wheat pasture enterprise.

    PubMed

    Beck, P; Hess, T; Hubbell, D; Hufstedler, G D; Fieser, B; Caldwell, J

    2014-03-01

    This research was designed to evaluate the effect of monensin (Elanco Animal Health, Greenfield, IN) supplementation via mineral or pressed protein block with or without a growth-promoting implant on performance of steers grazing wheat pasture in Arkansas over 2 yr. Preconditioned steers (n = 360, BW = 238 ± 5.1 kg) grazed 15 1.6-ha wheat pastures in the fall (n = 60 steers each fall, stocking rate of 2.5 steers/ha) or 30 0.8-ha wheat pastures in the spring (n = 120 steers each spring, stocking rate of 5 steers/ha). Steers in each pasture were given free-choice access to nonmedicated mineral (CNTRL; MoorMan's WeatherMaster Range Minerals A 646AAA; ADM Alliance Nutrition, Inc., Quincy, IL), or were supplemented with monensin (Elanco Animal Health, Greenfield, IN) via mineral containing 1.78 g monensin/kg (RMIN; MoorMan's Grower Mineral RU-1620 590AR; ADM Alliance Nutrition, Inc.), or pressed protein block containing 0.33 g monensin/kg (RBLCK; MoorMan's Mintrate Blonde Block RU; ADM Alliance Nutrition, Inc.). Additionally, one-half of the steers in each pasture were implanted (IMPL) with 40 mg trenbolone acetate and 8 mg estradiol (Component TE-G with Tylan; Elanco Animal Health). There was no interaction (P ≥ 0.71) between supplement treatment and growth-promoting implants, and ADG for RMIN and RBLCK were increased (P < 0.01) over CNTRL by 0.07 to 0.09 kg/d, respectively. Implanting steers with Component TE-G increased (P < 0.01) ADG by 0.14 kg/d. The combination of these growth-promoting technologies are a cost-effective means of increasing beef production by 22% without increasing level of supplementation or pasture acreage. Utilizing ionophores and implants together for wheat pasture stocker cattle decreased cost of gain by 26%. Utilizing both IMPL and monensin increased net return by $30 to $54/steer for RMIN or $18 to $43/steer for RBLCK compared with UNIMPL CNTRL at Low and High values of BW gain, respectively.

  9. Verification of fresh grass feeding, pasture grazing and organic farming by cows farm milk fatty acid profile.

    PubMed

    Capuano, Edoardo; van der Veer, Grishja; Boerrigter-Eenling, Rita; Elgersma, Anjo; Rademaker, Jan; Sterian, Adriana; van Ruth, Saskia M

    2014-12-01

    The present study investigated the use of fatty acid (FA) profiling in combination with chemometric modelling to verify claims for cow milk in terms of fresh grass feeding, pasture grazing and organic/biodynamic farming. The FA profile was determined for 113 tank milk samples collected in the Netherlands from 30 farms over four different months, and used to develop classification models based on the PLS-DA algorithm. Milk from cows with daily rations of fresh grass could be successfully distinguished from milk from cows with no fresh grass in their diet. Milk from cows at pasture could easily be distinguished from milk from stabled cows without fresh grass in the diet, but the correct prediction of milk from stabled cows fed fresh grass indoors proved difficult. The FA profile of organic/biodynamic milk was different compared to conventional milk but an unequivocal discrimination was not possible either in summer or in winter.

  10. Low Spatial and Inter-Annual Variability in Evaporation from an Intensively Grazed Temperate Pasture System in New Zealand

    NASA Astrophysics Data System (ADS)

    Pronger, J.; Campbell, D.; Clearwater, M.; Rutledge, S.; Wall, A.; Schipper, L. A.

    2015-12-01

    Ecosystem scale measurements of evaporation (E) from intensively managed pasture systems are scarce and are important for informing water resource decision making, drought forecasting, and validation of Earth system models and remote sensing. We measured E from intensively grazed, unirrigated, ryegrass and clover pasture in New Zealand using eddy covariance (EC) for three years (2012 - 2014). Spatial variation in E was less than 3% during the initial study period when up to three sites were operating simultaneously. Inter-annual variability was also less than 3% over the three consecutive years (710 - 730 mm) at one site. The absence of spatial and inter-annul variation largely occurred because E was strongly controlled by net radiation (daytime half-hourly data r2 = 0.83, p < 0.01) which was relatively consistent between sites and years. However, soil moisture decreased surface conductance during seasonal drought constraining E relative to net radiation. Variation in drought severity between years caused variation in seasonal E between years, for example, a relatively severe autumn drought in 2013 reduced E over autumn by 13% compared to 2012. Coincidentally, two unusually large spring and early summer rainfall events during warm conditions later in 2013 increased summer E by 12% compared to 2012 and therefore similar annual totals were measured between years. The FAO56 Penman-Monteith model was able to accurately predict daily E over an annual cycle (r2 = 0.81) to within 5 % of measured cumulative E with a crop factor of 0.96 (determined under non water-limiting conditions) and a water stress coefficient to account for soil moisture restrictions. Intensive grazing events, that remove a large fraction of standing pasture biomass, were found to have no effect on evaporation. The absence of a grazing effect suggests that leaf area was not an important control of E, likely because increases in soil E were able to compensate for decreased transpiration.

  11. Mixed grazing systems of goats with cattle in tropical conditions: an alternative to improving animal production in the pasture.

    PubMed

    d'Alexis, S; Periacarpin, F; Jackson, F; Boval, M

    2014-08-01

    Mixed grazing systems combining sheep and cattle have shown better growth performance for one or both species. This observation has been attributed to their complementary feeding behaviour and the reduced host infection by gastrointestinal nematodes. Less attention has been paid to mixed grazing systems combining goats and cattle. Here, continuously grazing goats mixed with cattle (M) were compared with control goats reared alone (C) under tropical conditions. The comparison was conducted with gastrointestinal nematode-infected (I) and non-infected (nI) goats. Thus, the four treatments were cattle with gastrointestinal nematode-infected goats (MI), gastrointestinal nematode-infected goats alone (CI), cattle with non-infected goats (MnI) and non-infected goats (CnI). Average daily gain (ADG, g/day) and grass production were measured for the four groups of animals (six goats and two heifers treated with MI or MnI) grazing for 3 months on 4 subplots. Monthly measurements were performed over 5-day periods. This pattern was replicated in space for a second set of four subplots and in time for six successive cohorts of animals (bands 1 to 6). The ADG of goats in mixed grazing conditions was higher than controls irrespective of the infection status (32.6 v. 18.4 g/day for MI v. CI; 44.2 v. 33.5 g/day for MnI v. CnI). Concomitantly, the average biomass was lower for mixed grazing animals compared with controls (174 v. 170 for MI and MnI; 235 v. 208 for CI and CnI, respectively), suggesting better use of the sward. For daily BW gain (g/kg DM), mixed grazing also yielded better results than the control (1.88 v. 0.52 g BW/kg DM per day for MI v. CI; 2.08 v. 1.47 g BW/kg DM per day for MnI and CnI). Mixed grazing of goats and heifers offers a promising alternative for increasing goat and overall animal production as well as improving the management of pastures.

  12. Soil organic carbon stocks and composition under grazed and ungrazed Kobresia pygmaea pasture of the Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Breidenbach, Andreas; Schleuß, Per; Kuzyakov, Yakov; Guggenberger, Georg

    2015-04-01

    Kobresia pastures represent the world's largest alpine ecosystem and an important sink but also a potential source of CO2. Specific features of Kobresia root mats provide unique mechanisms protecting against degradation even by moderate overgrazing and leading to large carbon storage in soil. Thus it is necessary to analyse how management- and/or climate-induced changes in above and belowground litter production affect the OC stock and composition in these grassland soils. We analyzed soils from a grazing exclosure experiment to study alterations using elemental analysis and analysis of solvent extractable as well as hydrolysable aliphatic lipids (e.g. n-alkanes, n-alkanols, n-alkanoic acids, as well as cutin- and suberin-derived hydroxy-fatty acids). We investigated bulk soils and density fractions taken from three different depth increments (0-5 cm, 5-15 cm and 15-35 cm) from two grazed and two ungrazed plots. Grazing exclosure resulted in an OC gain up to 1.0 kg m-2 at the site where plant community changes after grazing cessation were most pronounced. These OC gains were caused by increased stocks of OC in the particulate fraction of the two deeper soil increments whereas the OC of the mineral associated fraction and the depth increment 0-5 cm showed no changes. Moreover, the concentration of solvent extractable C16 and C18 acids decreased in the particulate fraction whereas the concentration of C24 and C26 acids increased. Our results show that seven years of grazing cessation increased the OC-pool with short turnover rates and changed its chemical composition, but had no major impact on the more stable OC pools of the mineral soil.

  13. Forage intake by and site and extent of digestion in beef cattle grazing midgrass prairie rangeland or plains bluestem pasture throughout the summer.

    PubMed

    Gunter, S A; McCollum, F T; Gillen, R L

    1997-02-01

    Eight beef steers fitted with esophageal (four steers/pasture) and 12 beef calves fitted ruminal and duodenal (six calves/pasture; beginning BW = 267 +/- 6 kg) cannulas grazed either midgrass prairie rangeland (excellent range condition; MIDGRASS) or plains bluestem (Bothriochloa ischaemum var. Plains) pasture (BLUESTEM) during mid-May, late June, mid-August, and mid-October of 1990 and 1991 in order to compare nutrient intake and digestion. Forage OM intake (OMI) by cattle grazing MIDGRASS or BLUESTEM was similar (P > .05) in June and August. In May and October, cattle grazing MIDGRASS consumed more (P < .05) OM than cattle grazing BLUESTEM. The extent of true ruminal OM digestion was similar (P > .05) between forage types except in October 1991, when the extent of digestion for BLUESTEM was greater (P < .05) than for MIDGRASS. The N intake by cattle interacted by year and forage (P < .05). Nitrogen intake by cattle grazing MIDGRASS tended to be lower in June and August than in May and October. The N intake by cattle grazing BLUESTEM peaked (P < .05) in August during 1990; however, N intake was lowest (P < .05) in August during 1991. Duodenal non-ammonia N (NAN) flow was higher (P < .05) in cattle grazing BLUESTEM than in cattle grazing MIDGRASS from May through August; however, duodenal NAN flow in cattle grazing BLUESTEM was lower (P < .05) in October 1991. Duodenal microbial N synthesis (grams/day) responded quadratically (P < .05) to total ruminal OM digestion (kilograms/day). Extent of true ruminal N digestion of both forages decreased (P < .05) as forage became more mature and lower in total N. Midgrass prairie seemed superior to BLUESTEM in May and October because of higher energy intakes and BLUESTEM seemed to be a good alternative to MIDGRASS during June through August, suggesting that these forages would make excellent complements. Furthermore, these data suggest that, in cattle grazing either forage, duodenal NAN flow was disproportionately high

  14. Genotype x environment interactions for postweaning performance in crossbred calves grazing winter wheat pasture or dormant native prairie.

    PubMed

    Phillips, W A; Brown, M A; Brown, A H; Coleman, S W

    2001-06-01

    Data from 403 calves from Angus, Brahman, and reciprocal-cross cows sired by Polled Hereford bulls were used to evaluate the impact of postweaning backgrounding forages on postweaning BW, gains, and carcass traits. Calves were born (spring of 1991 through 1994) and reared on either endophyte-infected tall fescue or common bermudagrass pastures. After weaning, calves were transported 360 km to the Grazinglands Research Laboratory, west of El Reno, OK, and, within breed and preweaning forage, were assigned to one of the following winter stocker treatments: 1) winter wheat pasture or 2) dormant native prairie plus supplemental CP. In March, winter stocker treatments were ended and calves were grazed as a single group on cool-season grasses until early July (1992, 1993, and 1994) or late May (1995), when the feedlot phase began. In the feedlot, calves were fed a high concentrate diet for an average of 120 d until a backfat thickness of > 10 mm was reached. Calves were shipped in truck load lots to Amarillo, TX (350 km), for processing and collection of carcass data. Averaged over calf breed group, calves wintered on wheat pasture gained faster (P < 0.01) during the stocker phase (0.71 vs 0.43 kg); had heavier (P < 0.01) final feedlot weights (535 vs 512 kg); lower feedlot (P < 0.01) ADG (1.37 vs 1.53 kg); heavier (P < 0.01) carcass weights (337 vs 315 kg); larger (P < 0.01) longissimus muscle (84.9 vs 81.8 cm2); higher percentage (P < 0.01) of kidney, heart, and pelvic fat (2.32 vs 2.26); and higher (P < 0.01) dressing percentage (62.2 vs 61.3) than calves backgrounded on native prairie. Maternal heterosis for stocker ADG was evident in calves backgrounded on native prairie but not on winter wheat (P < 0.10), but the two environments were similar in maternal heterosis for feedlot ADG and carcass traits. Calves wintered on native prairie were restricted in growth and expressed compensatory gain during the feedlot phase but not during the spring stocker phase. Dormant

  15. Genotype x environment interactions for postweaning performance in crossbred calves grazing winter wheat pasture or dormant native prairie.

    PubMed

    Phillips, W A; Brown, M A; Brown, A H; Coleman, S W

    2001-06-01

    Data from 403 calves from Angus, Brahman, and reciprocal-cross cows sired by Polled Hereford bulls were used to evaluate the impact of postweaning backgrounding forages on postweaning BW, gains, and carcass traits. Calves were born (spring of 1991 through 1994) and reared on either endophyte-infected tall fescue or common bermudagrass pastures. After weaning, calves were transported 360 km to the Grazinglands Research Laboratory, west of El Reno, OK, and, within breed and preweaning forage, were assigned to one of the following winter stocker treatments: 1) winter wheat pasture or 2) dormant native prairie plus supplemental CP. In March, winter stocker treatments were ended and calves were grazed as a single group on cool-season grasses until early July (1992, 1993, and 1994) or late May (1995), when the feedlot phase began. In the feedlot, calves were fed a high concentrate diet for an average of 120 d until a backfat thickness of > 10 mm was reached. Calves were shipped in truck load lots to Amarillo, TX (350 km), for processing and collection of carcass data. Averaged over calf breed group, calves wintered on wheat pasture gained faster (P < 0.01) during the stocker phase (0.71 vs 0.43 kg); had heavier (P < 0.01) final feedlot weights (535 vs 512 kg); lower feedlot (P < 0.01) ADG (1.37 vs 1.53 kg); heavier (P < 0.01) carcass weights (337 vs 315 kg); larger (P < 0.01) longissimus muscle (84.9 vs 81.8 cm2); higher percentage (P < 0.01) of kidney, heart, and pelvic fat (2.32 vs 2.26); and higher (P < 0.01) dressing percentage (62.2 vs 61.3) than calves backgrounded on native prairie. Maternal heterosis for stocker ADG was evident in calves backgrounded on native prairie but not on winter wheat (P < 0.10), but the two environments were similar in maternal heterosis for feedlot ADG and carcass traits. Calves wintered on native prairie were restricted in growth and expressed compensatory gain during the feedlot phase but not during the spring stocker phase. Dormant

  16. More milk from forage: Milk production, blood metabolites, and forage intake of dairy cows grazing pasture mixtures and spatially adjacent monocultures.

    PubMed

    Pembleton, Keith G; Hills, James L; Freeman, Mark J; McLaren, David K; French, Marion; Rawnsley, Richard P

    2016-05-01

    There is interest in the reincorporation of legumes and forbs into pasture-based dairy production systems as a means of increasing milk production through addressing the nutritive value limitations of grass pastures. The experiments reported in this paper were undertaken to evaluate milk production, blood metabolite concentrations, and forage intake levels of cows grazing either pasture mixtures or spatially adjacent monocultures containing perennial ryegrass (Lolium perenne), white clover (Trifolium repens), and plantain (Plantago lanceolata) compared with cows grazing monocultures of perennial ryegrass. Four replicate herds, each containing 4 spring-calving, cross-bred dairy cows, grazed 4 different forage treatments over the periods of early, mid, and late lactation. Forage treatments were perennial ryegrass monoculture (PRG), a mixture of white clover and plantain (CPM), a mixture of perennial ryegrass, white clover, and plantain (RCPM), and spatially adjacent monocultures (SAM) of perennial ryegrass, white clover, and plantain. Milk volume, milk composition, blood fatty acids, blood β-hydroxybutyrate, blood urea N concentrations, live weight change, and estimated forage intake were monitored over a 5-d response period occurring after acclimation to each of the forage treatments. The acclimation period for the early, mid, and late lactation experiments were 13, 13, and 10 d, respectively. Milk yield (volume and milk protein) increased for cows grazing the RCPM and SAM in the early lactation experiment compared with cows grazing the PRG, whereas in the mid lactation experiment, milk fat increased for the cows grazing the RCPM and SAM when compared with the PRG treatments. Improvements in milk production from grazing the RCPM and SAM treatments are attributed to improved nutritive value (particularly lower neutral detergent fiber concentrations) and a potential increase in forage intake. Pasture mixtures or SAM containing plantain and white clover could be a

  17. Beef heifer growth and reproductive performance following two levels of pasture allowance during the fall grazing period.

    PubMed

    Bailey, B L; Griggs, T C; Rayburn, E B; Krause, K M

    2014-08-01

    The objective of this study was to compare heifer growth and reproductive performance following 2 levels of stockpiled fall forage allowance of orchardgrass (30.5%) and tall fescue (14.1%). Spring-born heifers (n = 203 and BW = 246 ± 28.9 kg) of primarily Angus background were allocated to 2 grazing treatments during the fall period (November 12 to December 17 in yr 1, November 7 to January 4 in yr 2, and November 7 to January 14 in yr 3) each replicated 3 times per year for 3 yr. Treatments consisted of daily pasture DM allowance of 3.5% of BW (LO) or daily pasture DM allowance of 7.0% of BW (HI) under strip-grazing management. Throughout the winter feeding period, mixed grass-legume haylage and soybean hulls were fed. Heifers were grazed as 1 group under continuous stocking after the winter period. Heifers in the LO group gained less than heifers in the HI group during the fall grazing period (0.12 vs. 0.40 kg/d; P < 0.0001). For each 1 10 g increase in NDF/kg fall pasture (DM basis), fall ADG decreased 0.14 kg (P = 0.01). During winter feeding, ADG was 0.30 and 0.39 kg/d for LO vs. HI heifers, respectively (P = 0.0008). During the spring grazing period (April 16 to May 24 in yr 1, April 22 to May 26 in yr 2, and April 5 to May 16 in yr 3), LO heifers had numerically greater ADG than HI heifers (1.38 vs. 1.30 kg/d; P = 0.64). Hip height (122.7 vs. 121.4 cm; P = 0.0055), BCS (5.8 vs. 5.6; P = 0.0057), and BW (356 vs. 335 kg; P < 0.0001) at the end of spring grazing was greater for HI than LO heifers. Heifers in the LO group compensated with greater summer ADG than heifers in the HI group (0.74 vs. 0.66 kg/d; P = 0.03). Total ADG from treatment initiation (November) through pregnancy diagnosis (August) was greater for HI than LO heifers (0.61 vs. 0.55 kg/d; P < 0.001) as was BW at pregnancy diagnosis (415 vs. 402 kg; P = 0.0055). Percentage of heifers reaching puberty by the time of AI was 34% for both groups (P = 0.93). Percentage of heifers becoming pregnant to

  18. Effects of nitrogen application rate and a nitrification inhibitor dicyandiamide on methanotroph abundance and methane uptake in a grazed pasture soil.

    PubMed

    Dai, Yu; Di, Hong J; Cameron, Keith C; He, Ji-Zheng

    2013-12-01

    Methane-oxidizing bacteria (methanotrophs) in the soil are a unique group of methylotrophic bacteria that utilize methane (CH4) as their sole source of carbon and energy which limit the flux of methane to the atmosphere from soils and consume atmospheric methane. A field experiment was conducted to determine the effect of nitrogen application rates and the nitrification inhibitor dicyandiamide (DCD) on the abundance of methanotrophs and on methane flux in a grazed pasture soil. Nitrogen (N) was applied at four different rates, with urea applied at 50 and 100 kg N ha(-1) and animal urine at 300 and 600 kg N ha(-1). DCD was applied at 10 kg ha(-1). The results showed that both the DNA and selected mRNA copy numbers of the methanotroph pmoA gene were not affected by the application of urea, urine or DCD. The methanotroph DNA and mRNA pmoA gene copy numbers were low in this soil, below 7.13 × 10(3) g(-1) soil and 3.75 × 10(3) μg(-1) RNA, respectively. Daily CH4 flux varied slightly among different treatments during the experimental period, ranging from -12.89 g CH4 ha(-1) day(-1) to -0.83 g CH4 ha(-1) day(-1), but no significant treatment effect was found. This study suggests that the application of urea fertilizer, animal urine returns and the use of the nitrification inhibitor DCD do not significantly affect soil methanotroph abundance or daily CH4 fluxes in grazed grassland soils.

  19. In-vivo estimates for the uptake of caesium-137 by cattle grazing contaminated pasture around the ESK and IRT estuaries, Cumbria, U.K.

    PubMed

    Sumerling, T J

    1981-12-01

    Sea water contaminated with diluted radioactive effluent from the Windscale nuclear complex in Cumbria periodically floods low-lying grazing pasture around the estuaries of the rivers Esk, Irt and Mite near Ravenglass. During 1979, an experiment was carried out to measure the transfer of caesium-137 from grass to muscle in cows grazing these pastures. Grass samples were taken in a vivo external gamma-ray measurements were made on cattle. A very low transfer coefficient was found, less than 9 X 10-4 days kg-1 with a best estimate of 4 X 10-4 days kg-1, compared with a more usual value of around 3 X 10-2 days kg-1. The low transfer seems to occur because the bulk of the caesium-137 on the grass is bound to resuspended estuarine surface sediment deposited during flooding. In this form, the caesium-137 is only poorly absorbed across the gut of the grazing cattle.

  20. Plant Identity Exerts Stronger Effect than Fertilization on Soil Arbuscular Mycorrhizal Fungi in a Sown Pasture.

    PubMed

    Zheng, Yong; Chen, Liang; Luo, Cai-Yun; Zhang, Zhen-Hua; Wang, Shi-Ping; Guo, Liang-Dong

    2016-10-01

    Arbuscular mycorrhizal (AM) fungi play key roles in plant nutrition and plant productivity. AM fungal responses to either plant identity or fertilization have been investigated. However, the interactive effects of different plant species and fertilizer types on these symbiotic fungi remain poorly understood. We evaluated the effects of the factorial combinations of plant identity (grasses Avena sativa and Elymus nutans and legume Vicia sativa) and fertilization (urea and sheep manure) on AM fungi following 2-year monocultures in a sown pasture field study. AM fungal extraradical hyphal density was significantly higher in E. nutans than that in A. sativa and V. sativa in the unfertilized control and was significantly increased by urea and manure in A. sativa and by manure only in E. nutans, but not by either fertilizers in V. sativa. AM fungal spore density was not significantly affected by plant identity or fertilization. Forty-eight operational taxonomic units (OTUs) of AM fungi were obtained through 454 pyrosequencing of 18S rDNA. The OTU richness and Shannon diversity index of AM fungi were significantly higher in E. nutans than those in V. sativa and/or A. sativa, but not significantly affected by any fertilizer in all of the three plant species. AM fungal community composition was significantly structured directly by plant identity only and indirectly by both urea addition and plant identity through soil total nitrogen content. Our findings highlight that plant identity has stronger influence than fertilization on belowground AM fungal community in this converted pastureland from an alpine meadow.

  1. Effect of grazing seedhead-suppressed tall fescue pasture on the vasoactivity of serotonin receptors

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous research has demonstrated that exposure to ergot alkaloids reduces vasoactivity of serotonin (5HT) receptors. Chemical suppression of tall fescue seedhead production is a tool to reduce the level of exposure to ergot alkaloids by a grazing animal. Therefore, the objective was to evaluate co...

  2. The behavior of sheep and goats co-grazing on pasture with different types of vegetation in the karst region.

    PubMed

    Bojkovski, D; Štuhec, I; Kompan, D; Zupan, M

    2014-06-01

    The Slovenian karst region and similar types of land are difficult to cultivate and often exposed to the process of being abandoned and overgrown with shrubs, trees, and brushwood. Co-grazing in a mixed group may be a way to optimize the management of sheep and goat flocks in such areas. To obtain more knowledge of the natural behavior of small ruminants, the experiment was designed on pasture in the mountain karst region. The experimental area was divided in 6 paddocks, of which 3 paddocks were covered with grass, herbs, and legumes (i.e., grassy paddock [GP]). In the other 3 paddocks the area was additionally overgrown with hazel, beech trees, and bushes (i.e., woody paddock [WP]). In a mixed flock of 40 Slovenian local sheep breed (Istrian Pramenka) and 10 crossbreed goats (Saanen × Alpine goat), 10 animals per species were focally observed during daylight (0500-2100 h). The natural behavior was scored on 12 d, 2 consecutive days in each of the paddocks. Animals were rotated between 6 paddocks according to the balanced schedule. They stayed at each paddock for 5 or 6 d. Observations started on the third day after moving the animals into a specific paddock, following 2 d of adaptation. The results indicated that botanically diverse paddock together with climate conditions affected the behavior. Goats were grazing more (P < 0.001) whereas sheep less in the WP (P = 0.05). In sheep, drinking and salt consumption were higher (both P < 0.001) in the WP, suggesting that salt triggered additional water consumption. The WP enabled conditions where more comfort behavior, that is, autogrooming (both species P < 0.001) and object grooming (both species P < 0.001), was performed. On the second day of observation, animals grazed more compared to the first day (both species P < 0.001), most likely due to lower forage availability. Goats drank (P < 0.001) and consumed more salt on the second day (P < 0.001). With higher temperature sheep and goats grazed less (P < 0.05 and P

  3. The behavior of sheep and goats co-grazing on pasture with different types of vegetation in the karst region.

    PubMed

    Bojkovski, D; Štuhec, I; Kompan, D; Zupan, M

    2014-06-01

    The Slovenian karst region and similar types of land are difficult to cultivate and often exposed to the process of being abandoned and overgrown with shrubs, trees, and brushwood. Co-grazing in a mixed group may be a way to optimize the management of sheep and goat flocks in such areas. To obtain more knowledge of the natural behavior of small ruminants, the experiment was designed on pasture in the mountain karst region. The experimental area was divided in 6 paddocks, of which 3 paddocks were covered with grass, herbs, and legumes (i.e., grassy paddock [GP]). In the other 3 paddocks the area was additionally overgrown with hazel, beech trees, and bushes (i.e., woody paddock [WP]). In a mixed flock of 40 Slovenian local sheep breed (Istrian Pramenka) and 10 crossbreed goats (Saanen × Alpine goat), 10 animals per species were focally observed during daylight (0500-2100 h). The natural behavior was scored on 12 d, 2 consecutive days in each of the paddocks. Animals were rotated between 6 paddocks according to the balanced schedule. They stayed at each paddock for 5 or 6 d. Observations started on the third day after moving the animals into a specific paddock, following 2 d of adaptation. The results indicated that botanically diverse paddock together with climate conditions affected the behavior. Goats were grazing more (P < 0.001) whereas sheep less in the WP (P = 0.05). In sheep, drinking and salt consumption were higher (both P < 0.001) in the WP, suggesting that salt triggered additional water consumption. The WP enabled conditions where more comfort behavior, that is, autogrooming (both species P < 0.001) and object grooming (both species P < 0.001), was performed. On the second day of observation, animals grazed more compared to the first day (both species P < 0.001), most likely due to lower forage availability. Goats drank (P < 0.001) and consumed more salt on the second day (P < 0.001). With higher temperature sheep and goats grazed less (P < 0.05 and P

  4. The Influence of Climate, Soil and Pasture Type on Productivity and Greenhouse Gas Emissions Intensity of Modeled Beef Cow-Calf Grazing Systems in Southern Australia

    PubMed Central

    Bell, Matthew J.; Cullen, Brendan R.; Eckard, Richard J.

    2012-01-01

    Simple Summary Livestock production systems and the agricultural industries in general face challenges to meet the global demand for food, whilst also minimizing their environmental impact through the production of greenhouse gas (GHG) emissions. Livestock grazing systems in southern Australia are low input and reliant on pasture as a low-cost source of feed. The balance between productivity and GHG emission intensity of beef cow-calf grazing systems was studied at sites chosen to represent a range of climatic zones, soil and pasture types. While the climatic and edaphic characteristics of a location may impact on the emissions from a grazing system, management to efficiently use pasture can reduce emissions per unit product. Abstract A biophysical whole farm system model was used to simulate the interaction between the historical climate, soil and pasture type at sites in southern Australia and assess the balance between productivity and greenhouse gas emissions (expressed in carbon dioxide equivalents, CO2-eq.) intensity of beef cow-calf grazing systems. Four sites were chosen to represent a range of climatic zones, soil and pasture types. Poorer feed quality and supply limited the annual carrying capacity of the kikuyu pasture compared to phalaris pastures, with an average long-term carrying capacity across sites estimated to be 0.6 to 0.9 cows/ha. A relative reduction in level of feed intake to productivity of calf live weight/ha at weaning by feeding supplementary feed reduced the average CO2-eq. emissions/kg calf live weight at weaning of cows on the kikuyu pasture (18.4 and 18.9 kg/kg with and without supplementation, respectively), whereas at the other sites studied an increase in intake level to productivity and emission intensity was seen (between 10.4 to 12.5 kg/kg without and with supplementary feed, respectively). Enteric fermentationand nitrous oxide emissions from denitrification were the main sources of annual variability in emissions intensity

  5. Substitution rate and milk yield response to corn silage supplementation of late-lactation dairy cows grazing low-mass pastures at 2 daily allowances in autumn.

    PubMed

    Pérez-Prieto, L A; Peyraud, J L; Delagarde, R

    2011-07-01

    Feed costs in dairy production systems may be decreased by extending the grazing season to periods such as autumn when grazing low-mass pastures is highly probable. The aim of this autumn study was to determine the effect of corn silage supplementation [0 vs. 8 kg of dry matter (DM) of a mixture 7:1 of corn silage and soybean meal] on pasture intake (PI), milk production, and grazing behavior of dairy cows grazing low-mass ryegrass pastures at 2 daily pasture allowances (PA; low PA=18 vs. high PA=30 kg of DM/cow above 2.5 cm). Twelve multiparous Holstein cows were used in a 4 × 4 Latin square design with 14-d periods. Pre-grazing pasture mass and pre-grazing plate meter pasture height averaged 1.8 t of DM/ha (above 2.5 cm) and 6.3 cm, respectively. The quality of the offered pasture (above 2.5 cm) was low because of dry conditions before and during the experiment (crude protein=11.5% of DM; net energy for lactation=5.15 MJ/kg of DM; organic matter digestibility=61.9%). The interaction between PA and supplementation level was significant for PI but not for milk production. Supplementation decreased PI from 11.6 to 7.6 kg of DM/d at low PA and from 13.1 to 7.3 kg of DM/d at high PA. The substitution rate was, therefore, lower at low than at high PA (0.51 vs. 0.75). Pasture intake increased with increasing PA in unsupplemented treatments, and was not affected by PA in supplemented treatments. Milk production averaged 13.5 kg/d and was greater at high than at low PA (+1.4 kg/d) and in supplemented than unsupplemented treatments (+5.2 kg/d). Milk fat concentration averaged 4.39% and was similar between treatments. Milk protein concentration increased from 3.37 to 3.51% from unsupplemented to supplemented treatments, and did not vary according to PA. Grazing behavior parameters were only affected by supplementation. On average, daily grazing time decreased (539 vs. 436 min) and daily ruminating time increased (388 vs. 486 min) from 0 to 8 kg of supplement DM. The PI

  6. Effects of stocking rate and corn gluten feed supplementation on performance of young beef cows grazing winter-stockpiled tall fescue-red clover pasture.

    PubMed

    Driskill, R; Russell, J R; Strohbehn, D R; Morrical, D G; Barnhart, S K; Lawrence, J D

    2007-06-01

    A winter grazing experiment was conducted to evaluate the effects of stocking rate and corn gluten feed supplementation on forage mass and composition and the BW and BCS of bred 2-yr-old cows grazing stockpiled forage during winter. Two 12.2-ha blocks containing Fawn, endophyte-free, tall fescue and red clover were each divided into 4 pastures of 2.53 or 3.54 ha. Hay was harvested from the pastures in June and August of 2003 and 2004, and N was applied at 50.5 kg/ha at the initiation of stockpiling in August. On October 22, 2003, and October 20, 2004, twenty-four 30-mo-old Angus-Simmental and Angus cows were allotted by BW and BCS to strip-graze for 147 d at 0.84 or 1.19 cow/ha. Eight similar cows were allotted to 2 dry lots and fed tall fescue-red clover hay ad libitum. Corn gluten feed was fed to cows in 2 pastures to maintain a mean BCS of 5 (9-point scale) at each stocking rate and in the dry lots (high supplementation level) or when weather prevented grazing (low supplementation level) in the remaining 2 pastures at each stocking rate. Mean concentrations of CP in yr 1 and 2 and IVDMD in yr 2 were greater (P < 0.10) in hay than stockpiled forage over the winter. At the end of grazing, cows fed hay in dry lots had greater (P < 0.05) BCS in yr 1 and greater (P < 0.10) BW in yr 2 than grazing cows. Grazing cows in the high supplementation treatment had greater (P < 0.10) BW than cows grazing at the low supplementation level in yr 1. Cows in the dry lots were fed 2,565 and 2,158 kg of hay DM/cow. Amounts of corn gluten feed supplemented to cows in yr 1 and 2 were 46 and 60 kg/ cow and did not differ (P = 0.33, yr 1; P = 0.50, yr 2) between cows fed hay or grazing stockpiled forage in either year. Estimated production costs were greater for cows in the dry lots because of hay feeding.

  7. Methane emission measurements in a cattle grazed pasture: a comparison of four methods

    NASA Astrophysics Data System (ADS)

    Tallec, T.; Klumpp, K.; Hensen, A.; Rochette, Y.; Soussana, J.-F.

    2012-10-01

    Methane (CH4) is considered to be the second main contributor to the global greenhouse gas effect, with major CH4 emissions originating from livestock. Accurate measurements from ruminating herds are required to improve emission coefficients used in national emission inventories, and to evaluate mitigation strategies. Previous measurements of enteric methane emissions from domestic animals have been carried out in artificial conditions such as laboratory chambers, or by fitting individual animals with capillary tubes and using SF6 as a tracer. Here we evaluated the reliability of eddy covariance technique (EC), already used for CO2 fluxes, for continuous CH4 measurements over a grazed field plot. Analyzer accuracy and reliability of eddy covariance technique were tested against field scale measurements with the SF6 tracer technique, Gaussian plume model and emission factors (i.e. IPCC). Results indicate a better agreement between EC and SF6 method when grazing heifers were parked close to the EC setup. However, a systematic underestimation of EC data appeared and even more when the distance between the source (ruminating heifers) and EC setup (mast) was increased. A two-dimensional footprint density function allowed to correct for the dilution effect on measured CH4 and led to a good agreement with results based on the SF6 technique (on average 231 and 252 g CH4 ha-1 over the grazing experiment, respectively). Estimations of the CH4 budgets for the whole grazing season were in line with estimates (i.e. emission factor coefficients) based on feed intake and animal live weight as well as SF6 technique. IPCC method Tier 2, however, led to an overestimation of CH4 fluxes on our site.

  8. Methane emission measurements in a cattle grazed pasture: A comparison of four methods

    NASA Astrophysics Data System (ADS)

    Tallec, Tiphaine; Klumpp, Katja; Darsonville, Olivier; Hensen, Adrian; Rochette, Yvanne

    2015-04-01

    Methane (CH4) is considered to be the second main contributor to the global greenhouse gas effect, with major CH4 emissions originating from livestock. Accurate measurements from ruminating herds are required to improve emission coefficients used in national emission inventories, and to evaluate mitigation strategies. Here we evaluated the reliability of eddy covariance technique (EC), for continuous CH4 measurements over a grazed field plot. Analyzer reliability of eddy covariance technique was tested against field scale measurements with the SF6 tracer technique [1], Gaussian plume model [2] and emission factors [3]. Results indicate a good agreement between methods. However, a systematic underestimation of EC data appeared when the distance between the source (ruminating heifers) and EC set-up (mast) was increased. A two-dimensional footprint density function allowed to correct for the dilution effect on measured CH4 and led to a good agreement with results based on the SF6 technique (on average 74 and 78 g CH4 head-1 day-1 (24 h) over the grazing experiment, respectively). Estimations of the CH4 budgets for the whole grazing season were in line with estimates (i.e. emission coefficients) based on feed intake and animal live weight as well as SF6 technique.

  9. Plant Identity Exerts Stronger Effect than Fertilization on Soil Arbuscular Mycorrhizal Fungi in a Sown Pasture.

    PubMed

    Zheng, Yong; Chen, Liang; Luo, Cai-Yun; Zhang, Zhen-Hua; Wang, Shi-Ping; Guo, Liang-Dong

    2016-10-01

    Arbuscular mycorrhizal (AM) fungi play key roles in plant nutrition and plant productivity. AM fungal responses to either plant identity or fertilization have been investigated. However, the interactive effects of different plant species and fertilizer types on these symbiotic fungi remain poorly understood. We evaluated the effects of the factorial combinations of plant identity (grasses Avena sativa and Elymus nutans and legume Vicia sativa) and fertilization (urea and sheep manure) on AM fungi following 2-year monocultures in a sown pasture field study. AM fungal extraradical hyphal density was significantly higher in E. nutans than that in A. sativa and V. sativa in the unfertilized control and was significantly increased by urea and manure in A. sativa and by manure only in E. nutans, but not by either fertilizers in V. sativa. AM fungal spore density was not significantly affected by plant identity or fertilization. Forty-eight operational taxonomic units (OTUs) of AM fungi were obtained through 454 pyrosequencing of 18S rDNA. The OTU richness and Shannon diversity index of AM fungi were significantly higher in E. nutans than those in V. sativa and/or A. sativa, but not significantly affected by any fertilizer in all of the three plant species. AM fungal community composition was significantly structured directly by plant identity only and indirectly by both urea addition and plant identity through soil total nitrogen content. Our findings highlight that plant identity has stronger influence than fertilization on belowground AM fungal community in this converted pastureland from an alpine meadow. PMID:27423979

  10. Reproduction Symposium: does grazing on biosolids-treated pasture pose a pathophysiological risk associated with increased exposure to endocrine disrupting compounds?

    PubMed

    Evans, N P; Bellingham, M; Sharpe, R M; Cotinot, C; Rhind, S M; Kyle, C; Erhard, H; Hombach-Klonisch, S; Lind, P M; Fowler, P A

    2014-08-01

    Biosolids (processed human sewage sludge), which contain low individual concentrations of an array of contaminants including heavy metals and organic pollutants such as polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB), and polychlorinated dibenzodioxins/polychlorinated dibenzofurans known to cause physiological disturbances, are increasingly being used as an agricultural fertilizer. This could pose a health threat to both humans and domestic and wild animal species. This review summarizes results of a unique model, used to determine the effects of exposure to mixtures of environmentally relevant concentrations of pollutants, in sheep grazed on biosolids-treated pastures. Pasture treatment results in nonsignificant increases in environmental chemical (EC) concentrations in soil. Whereas EC concentrations were increased in some tissues of both ewes and their fetuses, concentrations were low and variable and deemed to pose little risk to consumer health. Investigation of the effects of gestational EC exposure on fetal development has highlighted a number of issues. The results indicate that gestational EC exposure can adversely affect gonadal development (males and females) and that these effects can impact testicular morphology, ovarian follicle numbers and health, and the transcriptome and proteome in adult animals. In addition, EC exposure can be associated with altered expression of GnRH, GnRH receptors, galanin receptors, and kisspeptin mRNA within the hypothalamus and pituitary gland, gonadotroph populations within the pituitary gland, and regional aberrations in thyroid morphology. In most cases, these anatomical and functional differences do not result in altered peripheral hormone concentrations or reproductive function (e.g., lambing rate), indicating physiological compensation under the conditions tested. Physiological compensation is also suggested from studies that indicate that EC effects may be greater when exposure occurs either

  11. Systemic granulomatous disease in Brazilian cattle grazing pasture containing vetch (Vicia spp).

    PubMed

    Fighera, Rafael A; Barros, Claudio S L

    2004-04-01

    Vetch associated disease (hairy vetch poisoning) was observed in 8 herds of dairy cows in the state of Rio Grande do Sul, southern Brazil. In the pasture where 4 of these 8 herds were, Vicia villosa was the only vetch species represented, while cattle in the remaining 4 herds had access to both V villosa and V sativa but with large predominance of the former. Observed clinical signs included fever, dramatic drop in milk yield, thickening and wrinkling of the skin with multifocal plaques of alopecia, pruritus, conjunctivitis, nasal and ocular serous discharge, loss of weight and diarrhea. The mean morbidity in the 8 affected herds, representing 219 cattle, was 11.1% and the mortality was 100%. The duration of the clinical disease varied from 10 to 30 d. Gross lesions consisted of multifocal to coalescing grey-white soft to moderately firm nodules which infiltrated several organs, but were particularly prominent in lymph nodes, adrenal, renal cortex, spleen, liver, and myocardium. Microscopically the lesions consisted of extensive cellular infiltration composed of variable proportions of epithelioid macrophages, lymphocytes, plasma cells, and multinucleated giant cells; variable numbers of eosinophils were present in the inflammatory foci of several organs, but they were more prominent in the myocardium.

  12. Does long-term pasture management influence spatial distribution of soil characteristics in Oklahoma

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Native prairie and winter wheat pastures are among the primary resources used to graze cattle in central Oklahoma. These forage resources are subject to numerous stressors that affect land condition including grazing, climate, soil fertility, and farming operations. Understanding responses of soil c...

  13. Why is Mineral-Associated Organic Matter Enriched in 15N? Evidence from Grazed Pasture Soil

    NASA Astrophysics Data System (ADS)

    Baisden, W. T.; Wells, N. S.; Mudge, P. L.; Clough, T. J.; Schipper, L. A.; Ghani, A.; Stevenson, B.

    2014-12-01

    Throughout the scientific literature, measurements across soil depth and density fractions suggest that, with few exceptions, mineral-associated organic matter (OM) has higher δ15N than non-mineral-associated OM. This implies that the δ15N difference between N inputs and mineral-stabilized OM may characterize the microbial processes involved in stabilization and mineral association. Yet current understanding of observed N isotope fractionation in terrestrial ecosystems suggests the large isotope effects are expressed during inorganic N transformations from NH4 to gaseous loss pathways of NH3 volatilization and denitrification. How can the relative importance of N isotope fractionation during OM stabilization versus loss pathways be resolved? We recently examined N isofluxes when a temporary nitrogen excess is created by urine deposition in a New Zealand dairy pasture. We found that the N isotopic composition of volatilized NH3, and NO3 available for leaching or denitrification could not be linked back to the added N using Rayleigh distillation models. Instead, the results imply that the added N was immobilized, and the N available for losses was increasingly derived from mineralization of organic matter during the course of the experiment. These results are consistent with recent evidence of enhanced OM mineralization in urine patches, understanding of N isotope mass balances and long-standing evidence that gross mineralization and immobilization fluxes greatly exceed net mineralization and nitrification, except at very high N saturation. These results suggest that where 15N enrichment occurs due to fractionating loss pathways, the isotope effects are primarily transmitted to immobilized N, forming 15N enriched stabilized OM. This further explains earlier findings that the δ15N of soil OM represents an integrated indicator of losses, reflecting the intensity and duration of pastoral agriculture. We suggest that development of an indicator based on δ15N in

  14. Energetic efficiency of milk synthesis in dual-purpose cows grazing tropical pastures.

    PubMed

    Aguilar-Pérez, Carlos Fernando; Ku-Vera, Juan Carlos; Magaña-Monforte, Juan Gabriel

    2011-04-01

    The aim of this study was to assess the energetic efficiency of milk synthesis by grazing dual-purpose cows with or without a starch-based supplement in tropical South Mexico. Forty-six Holstein × Zebu cows were used in a 2 × 2 × 2 factorial design. Factors analysed were diet (supplemented, unsupplemented), age (young: 1-2 calvings, mature: >3 calvings) and day of lactation (21 and 84 days post-calving). The supplement represented about 30% of estimated dry matter (DM) intake. Grass intake was measured using the n-alkane technique at 21 and 84 days post-calving when calculations of efficiency were performed. Efficiency for milk synthesis was reported as feed conversion efficiency (FCE, kilograms of milk per kilogram of DM intake), gross energetic efficiency (GEE, milk energy output/metabolisable energy (ME) intake) and efficiency of ME use for lactation (k(l), adjusted to zero energy balance). There were no interactions between factors. FCE and GEE were not different between diets, but supplemented cows had a lower (p < 0.01) k(l) value (0.62) than unsupplemented cows (0.67), suggesting a diverted partition of nutrients towards body tissue. Mature cows were more efficient (p < 0.001) than young cows in terms of FCE (1.13 vs 0.87) and GEE (0.34 vs 0.26), but equal in terms of k(l) (0.65). FCE (1.10 vs 0.90) and GEE (0.34 vs 0.27) were both higher on day 21 compared with day 84 post-calving, with a trend for a higher k(l) in early lactation. Dual-purpose cows used tropical grasses efficiently for milk synthesis, and higher milk yield observed in supplemented cows was due to a higher intake of nutrients rather than a higher energetic efficiency.

  15. The importance of ingested soils in supplying fluorine and lead to sheep grazing contaminated pastures in the Peak District mining area of Derbyshire, UK.

    PubMed

    Abrahams, Peter W; Blackwell, Nia L

    2013-12-01

    For sheep grazing pastures in areas of mineralisation and former metalliferous mining activity, an excessive intake of potentially harmful elements (PHEs) such as fluorine (F) and lead (Pb) can result in clinical and subclinical toxicity. The prime aim of our work was to calculate the intakes of both of these PHEs by sheep grazing pastures in the mineralised/mined Peak District area of Derbyshire. The bi-monthly sampling of topsoils (0-15 cm depth) and the faeces of sheep from fields at seven farms was undertaken for a 1-year period. These samples were analysed for titanium that allowed the rates of soil ingestion (and hence also herbage ingestion since we assume that the sheep have an overall diet of 1 kg dry matter (DM)/day) to be determined. Our findings were then combined with previously published soil and soil-free pasture herbage F and Pb concentrations determined from the seven farms to calculate the intakes of both PHEs. The results show seasonal variations of soil ingestion at the seven farms ranging from <0.1 to 20.1 % of the DM intake (median=3 %), with the highest rates of ingestion being associated with the winter-spring (i.e. December-April) period. Our calculations show that at some farms, sheep can be exposed to dietary concentrations in excess of recommended guidelines potentially throughout the whole year, though livestock movement to less-contaminated pastures would lessen any toxic impact. Because the soil concentrations are greater than those associated with soil-free pasture herbage, ingested soils are the main dietary source of Pb and (especially) F to sheep. However, subjecting freshly sampled topsoils to sequential extraction procedures undertaken in the laboratory indicates that the majority of Pb and (especially) F may not be readily soluble in the ovine digestion system, so reducing the quantities of both PHEs available for absorption.

  16. Inorganic fertilizer and poultry-litter manure amendments alter the soil microbial communities in agricultural systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of agricultural land management practices on soil prokaryotic diversity are not well described. We investigated three land usage systems (row cropped, ungrazed pasture, and cattle-grazed pasture) and two fertilizer systems (inorganic fertilizer or IF and poultry-litter or PL) and compare...

  17. Performance, forage utilization, and ergovaline consumption by beef cows grazing endophyte fungus-infected tall fescue, endophyte fungus-free tall fescue, or orchardgrass pastures.

    PubMed

    Peters, C W; Grigsby, K N; Aldrich, C G; Paterson, J A; Lipsey, R J; Kerley, M S; Garner, G B

    1992-05-01

    Two 120-d trials (May to September, 1988 and 1989) determined the effects of grazing tall fescue (two varieties) or orchardgrass on forage intake and performance by beef cows. Each summer, 48 cow-calf pairs grazed endophyte-infected Kentucky-31 tall fescue (KY-31), endophyte-free Mozark tall fescue (MOZARK), or Hallmark orchardgrass (OG) pastures (16 pairs/treatment). Forage OM intakes and digestibilities were determined during June and August each year. Cow and calf BW and milk production were determined every 28 d. During June of both years, OM intakes did not differ (P greater than .10) among treatments. During August of 1988, intakes were 18% lower (P less than .05) by KY-31 cows (1.6% of BW) than by MOZARK or OG cows (average 1.95% of BW); however, no differences (P greater than .10) were measured in August of 1989. Estimates of ergovaline consumption during June from KY-31 were between 4.2 (1988) and 6.0 mg/d (1989), whereas August estimates were between 1.1 (1988) and 2.8 mg/d (1989). Ergovaline in MOZARK estrusa was below detection limits, except in August of 1989. Cows that grazed KY-31 lost three times (P less than .01) more BW than cows that grazed MOZARK or OG (42 vs 9 and 13 kg, respectively). Milk production by KY-31 cows was 25% lower (P less than .01) than that by cows that grazed MOZARK or OG (6.0 vs average of 8.0 kg/d). Similarly, slower (P less than .01) calf gains were noted for KY-31 than for MOZARK or OG (.72 vs .89 and .88 kg/d, respectively). Cows grazing KY-31 experienced accelerated BW loss and reduced milk production and weaned lighter calves than did cows grazing MOZARK or OG. Decreased performance was not explained by consistently reduced forage intakes; hence, altered nutrient utilization was suspected.

  18. Influence of fresh alfalfa supplementation on fat skatole and indole concentration and chop odour and flavour in lambs grazing a cocksfoot pasture.

    PubMed

    Devincenzi, T; Prunier, A; Meteau, K; Nabinger, C; Prache, S

    2014-12-01

    We investigated the influence of the level of fresh alfalfa supplementation on fat skatole and indole concentration and chop sensory attributes in grazing lambs. Four groups of nine male Romane lambs grazing a cocksfoot pasture were supplemented with various levels of alfalfa for at least 60days before slaughter. Perirenal fat skatole concentration was higher for lambs that consumed alfalfa than for those that consumed only cocksfoot. The intensity of 'animal' odour in the lean part of the chop and of 'animal' flavour in both the lean and fat parts of the chop, evaluated by a trained sensory panel, increased from the lowest level of alfalfa supplementation onwards and did not increase further with increasing levels of alfalfa supplementation. The outcome of this study therefore suggests that these sensory attributes may reach a plateau when perirenal fat skatole concentration is in the range 0.16-0.24μg/g of liquid fat. PMID:25089784

  19. Impact of US Brown Swiss genetics on milk quality from low-input herds in Switzerland: interactions with grazing intake and pasture type.

    PubMed

    Stergiadis, S; Bieber, A; Franceschin, E; Isensee, A; Eyre, M D; Maurer, V; Chatzidimitriou, E; Cozzi, G; Bapst, B; Stewart, G; Gordon, A; Butler, G

    2015-05-15

    This study investigated the effect of, and interactions between, contrasting crossbreed genetics (US Brown Swiss [BS] × Improved Braunvieh [BV] × Original Braunvieh [OB]) and feeding regimes (especially grazing intake and pasture type) on milk fatty acid (FA) profiles. Concentrations of total polyunsaturated FAs, total omega-3 FAs and trans palmitoleic, vaccenic, α-linolenic, eicosapentaenoic and docosapentaenoic acids were higher in cows with a low proportion of BS genetics. Highest concentrations of the nutritionally desirable FAs, trans palmitoleic, vaccenic and eicosapentaenoic acids were found for cows with a low proportion of BS genetics (0-24% and/or 25-49%) on high grazing intake (75-100% of dry matter intake) diets. Multivariate analysis indicated that the proportion of OB genetics is a positive driver for nutritionally desirable monounsaturated and polyunsaturated FAs while BS genetics proportion was positive driver for total and undesirable individual saturated FAs. Significant genetics × feeding regime interactions were also detected for a range of FAs.

  20. The effects of protein supplement on leptin concentrations in lambs and meat goat kids grazing Bermudagrass pastures in Central Oklahoma

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lambs and kids weaned and pastured on bermudagrass (BG; Cynodon dactylon) may not receive enough protein to reach maximal growth during mid to late summer when protein in BG pastures declines. As an indicator of physiological status, leptin is an adipocyte-derived hormone that increases as body cond...

  1. Runoff phosphorus in a small rotationally-grazed pasture in Georgia with no history of broiler litter application

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pastures are sources of phosphorus (P) into water sources and can contribute to eutrophication and impairment. Close to 4 million ha of land in the Southern Coastal Plain and the Southern Piedmont in eastern USA is used for pasture and hay production. We present an 11-yr (1999 to 2009) of dissolved ...

  2. Upscaling NZ-DNDC using a regression based meta-model to estimate direct N2O emissions from New Zealand grazed pastures.

    PubMed

    Giltrap, Donna L; Ausseil, Anne-Gaëlle E

    2016-01-01

    The availability of detailed input data frequently limits the application of process-based models at large scale. In this study, we produced simplified meta-models of the simulated nitrous oxide (N2O) emission factors (EF) using NZ-DNDC. Monte Carlo simulations were performed and the results investigated using multiple regression analysis to produce simplified meta-models of EF. These meta-models were then used to estimate direct N2O emissions from grazed pastures in New Zealand. New Zealand EF maps were generated using the meta-models with data from national scale soil maps. Direct emissions of N2O from grazed pasture were calculated by multiplying the EF map with a nitrogen (N) input map. Three meta-models were considered. Model 1 included only the soil organic carbon in the top 30cm (SOC30), Model 2 also included a clay content factor, and Model 3 added the interaction between SOC30 and clay. The median annual national direct N2O emissions from grazed pastures estimated using each model (assuming model errors were purely random) were: 9.6GgN (Model 1), 13.6GgN (Model 2), and 11.9GgN (Model 3). These values corresponded to an average EF of 0.53%, 0.75% and 0.63% respectively, while the corresponding average EF using New Zealand national inventory values was 0.67%. If the model error can be assumed to be independent for each pixel then the 95% confidence interval for the N2O emissions was of the order of ±0.4-0.7%, which is much lower than existing methods. However, spatial correlations in the model errors could invalidate this assumption. Under the extreme assumption that the model error for each pixel was identical the 95% confidence interval was approximately ±100-200%. Therefore further work is needed to assess the degree of spatial correlation in the model errors.

  3. Field trial assessment of biological, chemical, and physical responses of soil to tillage intensity, fertilization, and grazing.

    PubMed

    Vargas Gil, Silvina; Becker, Analia; Oddino, Claudio; Zuza, Mónica; Marinelli, Adriana; March, Guillermo

    2009-08-01

    Soil microbial populations can fluctuate in response to environmental changes and, therefore, are often used as biological indicators of soil quality. Soil chemical and physical parameters can also be used as indicators because they can vary in response to different management strategies. A long-term field trial was conducted to study the effects of different tillage systems (NT: no tillage, DH: disc harrow, and MP: moldboard plough), P fertilization (diammonium phosphate), and cattle grazing (in terms of crop residue consumption) in maize (Zea mays L.), sunflower (Heliantus annuus L.), and soybean (Glycine max L.) on soil biological, chemical, and physical parameters. The field trial was conducted for four crop years (2000/2001, 2001/2002, 2002/2003, and 2003/2004). Soil populations of Actinomycetes, Trichoderma spp., and Gliocladium spp. were 49% higher under conservation tillage systems, in soil amended with diammonium phosphate (DAP) and not previously grazed. Management practices also influenced soil chemical parameters, especially organic matter content and total N, which were 10% and 55% higher under NT than under MP. Aggregate stability was 61% higher in NT than in MP, 15% higher in P-fertilized soil, and also 9% higher in not grazed strips, bulk density being 12% lower in NT systems compared with MP. DAP application and the absence of grazing also reduced bulk density (3%). Using conservation tillage systems, fertilizing crops with DAP, and avoiding grazing contribute to soil health preservation and enhanced crop production. PMID:19533217

  4. Field Trial Assessment of Biological, Chemical, and Physical Responses of Soil to Tillage Intensity, Fertilization, and Grazing

    NASA Astrophysics Data System (ADS)

    Vargas Gil, Silvina; Becker, Analia; Oddino, Claudio; Zuza, Mónica; Marinelli, Adriana; March, Guillermo

    2009-08-01

    Soil microbial populations can fluctuate in response to environmental changes and, therefore, are often used as biological indicators of soil quality. Soil chemical and physical parameters can also be used as indicators because they can vary in response to different management strategies. A long-term field trial was conducted to study the effects of different tillage systems (NT: no tillage, DH: disc harrow, and MP: moldboard plough), P fertilization (diammonium phosphate), and cattle grazing (in terms of crop residue consumption) in maize ( Zea mays L.), sunflower ( Heliantus annuus L.), and soybean ( Glycine max L.) on soil biological, chemical, and physical parameters. The field trial was conducted for four crop years (2000/2001, 2001/2002, 2002/2003, and 2003/2004). Soil populations of Actinomycetes, Trichoderma spp., and Gliocladium spp. were 49% higher under conservation tillage systems, in soil amended with diammonium phosphate (DAP) and not previously grazed. Management practices also influenced soil chemical parameters, especially organic matter content and total N, which were 10% and 55% higher under NT than under MP. Aggregate stability was 61% higher in NT than in MP, 15% higher in P-fertilized soil, and also 9% higher in not grazed strips, bulk density being 12% lower in NT systems compared with MP. DAP application and the absence of grazing also reduced bulk density (3%). Using conservation tillage systems, fertilizing crops with DAP, and avoiding grazing contribute to soil health preservation and enhanced crop production.

  5. Effects of nitrogen application rate and a nitrification inhibitor dicyandiamide on ammonia oxidizers and N2O emissions in a grazed pasture soil.

    PubMed

    Dai, Yu; Di, Hong J; Cameron, Keith C; He, Ji-Zheng

    2013-11-01

    Ammonia oxidizers, including ammonia oxidizing bacteria (AOB) and ammonia oxidizing archaea (AOA) are important drivers of a key step of the nitrogen cycle - nitrification, which affects the production of the potent greenhouse gas, nitrous oxide (N2O). A field experiment was conducted to determine the effect of nitrogen application rates and the nitrification inhibitor dicyandiamide (DCD) on the abundance of AOB and AOA and on N2O emissions in a grazed pasture soil. Nitrogen (N) was applied at four different rates, with urea applied at 50 and 100 kg N ha(-1) and animal urine at 300 and 600 kg N ha(-1). DCD was applied to some of the N treatments at 10 kg ha(-1). The results showed that the AOB amoA gene copy numbers were greater than those of AOA. The highest ratio of the AOB to AOA amoA gene copy numbers was 106.6 which occurred in the urine-N 600 treatment. The AOB amoA gene copy numbers increased with increasing nitrogen application rates. DCD had a significant impact in reducing the AOB amoA gene copy numbers especially in the high nitrogen application rates. N2O emissions increased with the N application rates. DCD had the most significant effect in reducing the daily and total N2O emissions in the highest nitrogen application rate. The greatest reduction of total N2O emissions by DCD was 69% in the urine-N 600 treatment. The reduction in the N2O emission factor by DCD ranged from 58% to 83%. The N2O flux and NO3(-)-N concentrations were significantly correlated to the growth of AOB, rather than AOA. This study confirms the importance of AOB in nitrification and the effect of DCD in inhibiting AOB growth and in decreasing N2O emissions in grazed pasture soils under field conditions.

  6. Insect habitat management in pasture systems

    NASA Astrophysics Data System (ADS)

    Martin, P. B.

    1983-01-01

    Two important habitat management strategies in pasture systems involve controlled burning and effective grazing manipulation schemes to maintain native climax grassland vegetation These climax grasslands have historically suffered less insect pest pressure than imported systems However, these types of grasslands are difficult to reestablish after relatively severe disruption by man Also, the proper diversity and stability is difficult to capture in developing imported systems. Imported pastures can exhibit substantial yields per land unit but are often composed of vegetation that rapidly mines nutrients stored by the native vegetation, and often need considerable inputs of fossil fuel, manufactured fertilizers and pesticides, because they are or become very susceptible to pestiferous insects. Habitat manipulation efforts can be effective in regulating forage pest populations below economic levels in imported pasture systems Such efforts include: 1) land use (coupled with plant diversity, grazing, and harvest manipulations), 2) sanitation (including controlled burning), 3) planting dates and harvest times (including grazing manipulations), 4) tillage methods, 5) fertilization, 6) trap crops, 7) water management, and 8) fire management for insect pest suppression and augmentation of natural enemies.

  7. Effect of nitrogen and phosphorus fertilization on the composition of rhizobacterial communities of two Chilean Andisol pastures.

    PubMed

    Jorquera, Milko A; Martínez, Oscar A; Marileo, Luis G; Acuña, Jacquelinne J; Saggar, Surinder; Mora, María L

    2014-01-01

    The effect of nitrogen (N) and phosphorus (P) fertilization on composition of rhizobacterial communities of volcanic soils (Andisols) from southern Chile at molecular level is poorly understood. This paper investigates the composition of rhizobacterial communities of two Andisols under pasture after 1- and 6-year applications of N (urea) and P (triple superphosphate). Soil samples were collected from two previously established sites and the composition of rhizobacterial communities was determined by denaturing gradient gel electrophoresis (PCR-DGGE). The difference in the composition and diversity between rhizobacterial communities was assessed by nonmetric multidimensional scaling (MDS) analysis and the Shannon-Wiener index. In Site 1 (fertilized for 1 year), PCR-DGGE targeting 16S rRNA genes and MDS analysis showed that moderate N application (270 kg N ha(-1) year(-1)) without P significantly changed the composition of rhizobacterial communities. However, no significant community changes were observed with P (240 kg P ha(-1) year(-1)) and N-P application (270 kg N ha(-1) year(-1) plus 240 kg P ha(-1) year(-1)). In Site 2 (fertilized for 6 years with P; 400 kg P ha(-1) year(-1)), PCR-DGGE targeting rpoB, nifH, amoA and alkaline phosphatase genes and MDS analysis showed changes in rhizobacterial communities only at the highest rate of N application (600 kg N ha(-1) year(-1)). Quantitative PCR targeting 16S rRNA genes also showed higher abundance of bacteria at higher N application. In samples from both sites, the Shannon-Wiener index did not show significant difference in the diversity of rhizobacterial communities. The changes observed in rhizobacterial communities coincide in N fertilized pastures with lower soil pH and higher pasture yields. This study indicates that N-P application affects the soil bacterial populations at molecular level and needs to be considered when developing fertilizer practices for Chilean pastoral Andisols. PMID

  8. Application of a linear regression model to assess the influence of urbanised areas and grazing pastures on the microbiological quality of rural streams.

    PubMed

    McGrane, Scott J; Tetzlaff, Doerthe; Soulsby, Chris

    2014-11-01

    Faecal coliform (FC) bacteria were used as a proxy of faecal indicator organisms (FIOs) to assess the microbiological pollution risk for eight mesoscale catchments with increasing lowland influence across north-east Scotland. This study sought to assess the impact of urban areas on microbial contaminant fluxes. Fluxes were lowest in upland catchments where populations are relatively low. By contrast, lowland catchments with larger settlements and a greater number of grazing populations have more elevated FC concentrations throughout the year. Peak FC counts occurred during the summer months (April-September) when biological activity is at its highest. Lowland catchments experience high FC concentrations throughout the year whereas upland catchments exhibit more seasonal variations with elevated summer conditions and reduced winter concentrations. A simple linear regression model based on catchment characteristics provided scope to predict FC fluxes. Percentage of improved grazing pasture and human population explained 90 and 62 % of the variation in mean annual FC concentrations. This approach provides scope for an initial screening tool to predict the impact of urban space and agricultural practice on FC concentrations at the catchment scale and can aid in pragmatic planning and water quality improvement decisions. However, greater understanding of the short-term dynamics is still required which would benefit from higher resolution sampling than the approach undertaken here.

  9. Impact of US Brown Swiss genetics on milk quality from low-input herds in Switzerland: interactions with grazing intake and pasture type.

    PubMed

    Stergiadis, S; Bieber, A; Franceschin, E; Isensee, A; Eyre, M D; Maurer, V; Chatzidimitriou, E; Cozzi, G; Bapst, B; Stewart, G; Gordon, A; Butler, G

    2015-05-15

    This study investigated the effect of, and interactions between, contrasting crossbreed genetics (US Brown Swiss [BS] × Improved Braunvieh [BV] × Original Braunvieh [OB]) and feeding regimes (especially grazing intake and pasture type) on milk fatty acid (FA) profiles. Concentrations of total polyunsaturated FAs, total omega-3 FAs and trans palmitoleic, vaccenic, α-linolenic, eicosapentaenoic and docosapentaenoic acids were higher in cows with a low proportion of BS genetics. Highest concentrations of the nutritionally desirable FAs, trans palmitoleic, vaccenic and eicosapentaenoic acids were found for cows with a low proportion of BS genetics (0-24% and/or 25-49%) on high grazing intake (75-100% of dry matter intake) diets. Multivariate analysis indicated that the proportion of OB genetics is a positive driver for nutritionally desirable monounsaturated and polyunsaturated FAs while BS genetics proportion was positive driver for total and undesirable individual saturated FAs. Significant genetics × feeding regime interactions were also detected for a range of FAs. PMID:25577126

  10. In silico exploration of the impact of pasture larvae contamination and anthelmintic treatment on genetic parameter estimates for parasite resistance in grazing sheep.

    PubMed

    Laurenson, Y C S M; Kyriazakis, I; Bishop, S C

    2012-07-01

    A mathematical model was developed to investigate the impact of level of Teladorsagia circumcincta larval pasture contamination and anthelmintic treatment on genetic parameter estimates for performance and resistance to parasites in sheep. Currently great variability is seen for published correlations between performance and resistance, with estimates appearing to vary with production environment. The model accounted for host genotype and parasitism in a population of lambs, incorporating heritable between-lamb variation in host-parasite interactions, with genetic independence of input growth and immunological variables. An epidemiological module was linked to the host-parasite interaction module via food intake (FI) to create a grazing scenario. The model was run for a population of lambs growing from 2 mo of age, grazing on pasture initially contaminated with 0, 1,000, 3,000, or 5,000 larvae/kg DM, and given either no anthelmintic treatment or drenched at 30-d intervals. The mean population values for FI and empty BW (EBW) decreased with increasing levels of initial larval contamination (IL(0)), with non-drenched lambs having a greater reduction than drenched ones. For non-drenched lambs the maximum mean population values for worm burden (WB) and fecal egg count (FEC) increased and occurred earlier for increasing IL(0), with values being similar for all IL(0) at the end of the simulation. Drenching was predicted to suppress WB and FEC, and cause reduced pasture contamination. The heritability of EBW for non-drenched lambs was predicted to be initially high (0.55) and decreased over time with increasing IL(0), whereas drenched lambs remained high throughout. The heritability of WB and FEC for all lambs was initially low (∼0.05) and increased with time to ∼0.25, with increasing IL(0) leading to this value being reached at faster rates. The genetic correlation between EBW and FEC was initially ∼-0.3. As time progressed the correlation tended towards 0, before

  11. Performance of Stocker Cattle Fed Hay and Protein Supplements during the Winter and Grazed on Wheat Pasture during the Spring

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The southern Great Plains region perennial warm- and annual cool-season grasses are used to grow stocker cattle for the US beef industry. In the fall, when calves are readily available, producers may purchase not only those needed for winter grazing, but also calves to be used the following spring w...

  12. Postgraze assessment of toxicosis symptoms for steers grazed on toxic and novel endophyte-infected tall fescue pasture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A 2-yr pen experiment was conducted using 18 crossbred Angus steers each year to evaluate changes in body temperature, vasoconstriction, and prolactin concentrations in steers previously grazed on toxic endophyte (Neotyphodium coenophialum)-infected Kentucky 31 tall fescue (Lolium arundinaceum) as c...

  13. Effect of herbage depletion on short-term foraging dynamics and diet quality of steers grazing wheat pastures.

    PubMed

    Gregorini, P; Gunter, S A; Bowman, M T; Caldwell, J D; Masino, C A; Coblentz, W K; Beck, P A

    2011-11-01

    Two complementary experiments were completed to assess short-term foraging dynamics, diet quality, and ruminal degradation kinetics of herbage consumed by steers with 3 levels of herbage depletion. Experiment 1 was a behavioral study in which 2 ruminally cannulated steers were allocated to grazing scenarios simulating 3 levels of herbage depletion. These treatments included an ungrazed sward (control), as well as medium and high levels of herbage depletion. Grazing scenarios were sampled for sward surface height and amount of green leaf and stem before being grazed. Foraging dynamics were determined through measurements of bite rate, bite depth, eating step rate, eating distance, potential area consumed while grazing, and bites and intake per eating step. Also, quality of potential herbage consumed was estimated from hand-plucked herbage. In Exp. 2, ruminal degradation kinetics of DM for samples of herbage consumed (masticate) by steers during Exp. 1 were assessed in situ using 5 ruminally cannulated steers. The immediately soluble, degraded, and undegraded DM fractions were determined. The DM disappearance rate and lag times were determined from a nonlinear regression model, and the effective degradability of DM was calculated. Herbage depletion resulted in increased eating steps/minute, as well as the potential area harvested while grazing (P < 0.05) and reduced herbage intake/eating step (P < 0.05). Neither the herbage potentially consumed nor the ruminal degradation kinetics was affected by extent of depletion (P > 0.05). Under these experimental conditions, steers adapted their foraging dynamic and were able to sustain diet quality in the short term. These results imply that behavioral adaptations would make diet quality less sensitive to certain levels of herbage depletion.

  14. Relationship between Reproductive Allocation and Relative Abundance among 32 Species of a Tibetan Alpine Meadow: Effects of Fertilization and Grazing

    PubMed Central

    Niu, Kechang; Schmid, Bernhard; Choler, Philippe; Du, Guozhen

    2012-01-01

    Background Understanding the relationship between species traits and species abundance is an important goal in ecology and biodiversity science. Although theoretical studies predict that traits related to performance (e.g. reproductive allocation) are most directly linked to species abundance within a community, empirical investigations have rarely been done. It also remains unclear how environmental factors such as grazing or fertilizer application affect the predicted relationship. Methodology We conducted a 3-year field experiment in a Tibetan alpine meadow to assess the relationship between plant reproductive allocation (RA) and species relative abundance (SRA) on control, grazed and fertilized plots. Overall, the studied plant community contained 32 common species. Principal Findings At the treatment level, (i) RA was negatively correlated with SRA on control plots and during the first year on fertilized plots. (ii) No negative RA–SRA correlations were observed on grazed plots and during the second and third year on fertilized plots. (iii) Seed size was positively correlated with SRA on control plots. At the plot level, the correlation between SRA and RA were not affected by treatment, year or species composition. Conclusions/Significance Our study shows that the performance-related trait RA can negatively affect SRA within communities, which is possibly due to the tradeoffs between clonal growth (for space occupancy) and sexual reproduction. We propose that if different species occupy different positions along these tradeoffs it will contribute to biodiversity maintenance in local communities or even at lager scale. PMID:22536385

  15. Temporary alterations to postpartum milking frequency affect whole-lactation milk production and the energy status of pasture-grazed dairy cows.

    PubMed

    Phyn, C V C; Kay, J K; Rius, A G; Morgan, S R; Roach, C G; Grala, T M; Roche, J R

    2014-11-01

    This study investigated the immediate and long-term effects of temporary alterations to postpartum milking frequency (MF) on milk production, body condition score (BCS), and indicators of energy status in pasture-grazed cows supplemented with concentrates. Multiparous Holstein-Friesian cows (n = 150) were randomly assigned to 1 of 5 groups at calving: milked twice daily (2 ×) throughout lactation (control), or milked either once daily (1 ×) or 3 times daily (3 ×) for 3 or 6 wk immediately postpartum, and then 2 × for the remainder of lactation. During wk 1 to 3 postpartum, cows milked 1 × produced 15% less milk and 17% less energy-corrected milk (ECM) than cows milked 2 ×. This immediate production loss increased to 20% less milk and 22% less ECM during wk 4 to 6 postpartum for cows that remained on 1 × milking; these animals also produced less than 1 × cows switched to 2 × milking after 3 wk. During wk 8 to 32, when all cows were milked 2 ×, those previously milked 1 × had sustained reductions in milk (-6%) and ECM (-8%) yields, which were not affected by the duration of reduced postpartum MF. In contrast, cows milked 3 × postpartum had 7% greater milk yields during wk 1 to 6 compared with 2 × controls, irrespective of the duration of increased MF. Milk yields also remained numerically greater (+5%) during wk 8 to 32 in cows previously milked 3 ×. Nevertheless, yields of ECM were not increased by 3 × milking, because of lower milk fat and protein contents that persisted for the rest of lactation. In addition, indicators of cow energy status reflected an increasing state of negative energy balance with increasing MF. Cows milked 1 × postpartum had greater plasma glucose and lower plasma nonesterified fatty acid concentrations during the reduced MF, and plasma glucose remained lower for 2 wk after cows had switched to 2 × milking. Moreover, BCS was improved relative to 2 × controls from wk 5 to 6. In contrast, cows milked 3 × had lower plasma

  16. Quantification of reductions in ammonia emissions from fertiliser urea and animal urine in grazed pastures with urease inhibitors for agriculture inventory: New Zealand as a case study.

    PubMed

    Saggar, Surinder; Singh, J; Giltrap, D L; Zaman, M; Luo, J; Rollo, M; Kim, D-G; Rys, G; van der Weerden, T J

    2013-11-01

    Urea is the key nitrogen (N) fertiliser for grazed pastures, and is also present in excreted animal urine. In soil, urea hydrolyses rapidly to ammonium (NH4(+)) and may be lost as ammonia (NH3) gas. Unlike nitrous oxide (N2O), however, NH3 is not a greenhouse gas although it can act as a secondary source of N2O, and hence contribute indirectly to global warming and stratospheric ozone depletion. Various urease inhibitors (UIs) have been used over the last 30 years to reduce NH3 losses. Among these, N-(n-butyl) thiophosphoric triamide (nBTPT), sold under the trade name Agrotain®, is currently the most promising and effective when applied with urea or urine. Here we conduct a critical analysis of the published and non-published data on the effectiveness of nBTPT in reducing NH3 emission, from which adjusted values for FracGASF (fraction of total N fertiliser emitted as NH3) and FracGASM (fraction of total N from, animal manure and urine emitted as NH3) for the national agriculture greenhouse gas (GHG) inventory are recommended in order to provide accurate data for the inventory. We use New Zealand as a case study to assess and quantify the overall reduction in NH3 emission from urea and animal urine with the application of UI nBTPT. The available literature indicates that an application rate of 0.025% w/w (nBTPT per unit of N) is optimum for reducing NH3 emissions from temperate grasslands. UI-treated urine studies gave highly variable reductions (11-93%) with an average of 53% and a 95% confidence interval of 33-73%. New Zealand studies, using UI-treated urea, suggest that nBTPT (0.025% w/w) reduces NH3 emissions by 44.7%, on average, with a confidence interval of 39-50%. On this basis, a New Zealand specific value of 0.055 for FracGASF FNUI (fraction of urease inhibitor treated total fertiliser N emitted as NH3) is recommended for adoption where urea containing UI are applied as nBTPT at a rate of 0.025% w/w. Only a limited number of published data sets are

  17. Metal exposure in cows grazing pasture contaminated by iron industry: Insights from magnetic particles used as tracers.

    PubMed

    Ayrault, Sophie; Catinon, Mickaël; Boudouma, Omar; Bordier, Louise; Agnello, Gregory; Reynaud, Stéphane; Tissut, Michel

    2016-05-01

    Magnetic particles (MP) emitted by an iron smelter were used to investigate the exposure of cows grazing on a grassland polluted by these MP and by large amounts of potentially toxic elements (PTE). The morphology as well as the chemical composition of the MP separated from cow dung were studied. Large amounts of typical MP were found (1.1 g kg(-1) dry weight) in the cow dung sampled from the exposed site, whereas these particles were absent from the reference unpolluted site. The ingested MP were mainly technogenic magnetic particles (TMP) emitted by the smelter. Considering the MP concentration in the grazed grass on the exposed site, it was concluded that cows absorb the MP not only from the grass but also from the soil surface. The results of a mild acidic leaching of the MP suggested that the particles were possibly submitted to a superficial dissolution in the abomasum, pointing at a potential route of transfer of the PTE originating from the TMP and leading into food chains. TMP were only a small part of the anthropogenic contamination having affected the soil and the dung. However, due to their unequivocal signature, TMP are a powerful tracer of the distribution of PTE in the different compartments constituting the food chains and the ecosystems. Furthermore, the measurement of the particle sizes gave evidence that a noticeable proportion of the MP could enter the respiratory tract. PMID:26986087

  18. Metal exposure in cows grazing pasture contaminated by iron industry: Insights from magnetic particles used as tracers.

    PubMed

    Ayrault, Sophie; Catinon, Mickaël; Boudouma, Omar; Bordier, Louise; Agnello, Gregory; Reynaud, Stéphane; Tissut, Michel

    2016-05-01

    Magnetic particles (MP) emitted by an iron smelter were used to investigate the exposure of cows grazing on a grassland polluted by these MP and by large amounts of potentially toxic elements (PTE). The morphology as well as the chemical composition of the MP separated from cow dung were studied. Large amounts of typical MP were found (1.1 g kg(-1) dry weight) in the cow dung sampled from the exposed site, whereas these particles were absent from the reference unpolluted site. The ingested MP were mainly technogenic magnetic particles (TMP) emitted by the smelter. Considering the MP concentration in the grazed grass on the exposed site, it was concluded that cows absorb the MP not only from the grass but also from the soil surface. The results of a mild acidic leaching of the MP suggested that the particles were possibly submitted to a superficial dissolution in the abomasum, pointing at a potential route of transfer of the PTE originating from the TMP and leading into food chains. TMP were only a small part of the anthropogenic contamination having affected the soil and the dung. However, due to their unequivocal signature, TMP are a powerful tracer of the distribution of PTE in the different compartments constituting the food chains and the ecosystems. Furthermore, the measurement of the particle sizes gave evidence that a noticeable proportion of the MP could enter the respiratory tract.

  19. Effects of increasing levels of grain supplementation on rumen environment and lactation performance of dairy cows grazing grass-legume pasture.

    PubMed

    Reis, R B; Combs, D K

    2000-12-01

    The impact of supplemental energy on nutrient utilization, fiber digestion, rumen fermentation, and lactation performance was evaluated in dairy cows grazing pastures composed of brome, orchardgrass, red clover, and alfalfa. Three amounts [0, 5, and 10 kg dry matter (DM)/d] of ground dry shelled corn-based concentrate were supplemented to nine rumen cannulated Holstein cows in a 3 x 3 Latin square replicated three times. Cows were on average 84+/-13 d in milk and producing 41.6+/-5.9 kg of milk/d at the beginning of the study. An increase in amounts of concentrate in the diets was associated with an increase in milk production, solids-corrected milk, and concentrations of milk protein and SNF. Milk fat percentage and milk urea nitrogen concentration decreased linearly with supplementation. Milk production and protein percentage were 21.8, 26.8, and 30.4 kg/d, and 2.85, 2.95, and 3.05% for the increasing levels of concentrate, respectively. Intake and digestibility of DM and organic matter (OM) increased as grain supplementation increased. Ruminal pH and total volatile fatty acid concentration (VFA) were not affected by supplementation or the amount of concentrate. Ruminal ammonia concentration was reduced by supplementation, presumably due to a decrease in N intake and greater use of ammonia-N for rumen microbial protein synthesis. Rumen fermentation varied throughout the day, with lower mean pH and higher VFA concentrations at night. Supplementation increased total OM intake, decreased forage OM intake, and increased the proportion of OM that was digested in the intestines. Total DM intake by grazing dairy cows can be increased using ground dry shelled corn-based concentrate without causing negative effects on forage digestion.

  20. Intake and Performance of Yearling Steers Grazing Guineagrass (Panicum maximum cv. Tanzânia) Pasture Supplemented with Different Energy Sources

    PubMed Central

    Santana, M. C. A.; Euclides, V. B. P.; Mancio, A. B.; Medeiros, S. R.; Costa, J. A. R.; Oliveira, R. L.

    2013-01-01

    The aim of this study was to evaluate the efficiency of supplements containing different energy sources in relation to mineral supplementation of steers grazing guineagrass (Panicum maximum cv Tanzânia) pasture, during the dry season. The experimental design was a randomized block with three treatments and four replications. The treatments consisted of a mineral supplementation and two other supplements, one based on corn seed and the other based on soybean hulls, and provided at 0.8% of body weight. Forty-eight, 12 month-old crossbred steers with an average initial body weight of 267 kg, were assigned to twelve paddocks (1,125 ha) of guineagrass. The animals that were fed with soybean hulls and corn seed presented a greater average daily gain (0.982 and 0.937) when compared with the mineral supplementation. Soybean hulls can be used as a satisfactory food source, replacing corn as an energy source in the supplementation of beef cattle without compromising animal performance. PMID:25049797

  1. Water quality and the grazing animal.

    PubMed

    Hubbard, R K; Newton, G L; Hill, G M

    2004-01-01

    Grazing animals and pasture production can affect water quality both positively and negatively. Good management practices for forage production protect the soil surface from erosion compared with conventionally produced crops. Grazing animals and pasture production can negatively affect water quality through erosion and sediment transport into surface waters, through nutrients from urine and feces dropped by the animals and fertility practices associated with production of high-quality pasture, and through pathogens from the wastes. Erosion and sediment transport is primarily associated with high-density stocking and/or poor forage stands. The two nutrients of primary concern relating to animal production are N and P. Nitrogen is of concern because high concentrations in drinking water in the NO(3) form cause methemoglobinemia (blue baby disease), whereas other forms of N (primarily nitrite, NO(2)) are considered to be potentially carcinogenic. Phosphorus in the PO(4) form is of concern because it causes eutrophication of surface water bodies. The effect of grazing animals on soil and water quality must be evaluated at both the field and watershed scales. Such evaluation must account for both direct input of animal wastes from the grazing animal and also applications of inorganic fertilizers to produce quality pastures. Watershed-scale studies have primarily used the approach of nutrient loadings per land area and nutrient removals as livestock harvests. A number of studies have measured nutrient loads in surface runoff from grazed land and compared loads with other land uses, including row crop agriculture and forestry. Concentrations in discharge have been regressed against standard grazing animal units per land area. Watersheds with concentrated livestock populations have been shown to discharge as much as 5 to 10 times more nutrients than watersheds in cropland or forestry. The other major water quality concern with grazing animals is pathogens, which may move

  2. Water quality and the grazing animal.

    PubMed

    Hubbard, R K; Newton, G L; Hill, G M

    2004-01-01

    Grazing animals and pasture production can affect water quality both positively and negatively. Good management practices for forage production protect the soil surface from erosion compared with conventionally produced crops. Grazing animals and pasture production can negatively affect water quality through erosion and sediment transport into surface waters, through nutrients from urine and feces dropped by the animals and fertility practices associated with production of high-quality pasture, and through pathogens from the wastes. Erosion and sediment transport is primarily associated with high-density stocking and/or poor forage stands. The two nutrients of primary concern relating to animal production are N and P. Nitrogen is of concern because high concentrations in drinking water in the NO(3) form cause methemoglobinemia (blue baby disease), whereas other forms of N (primarily nitrite, NO(2)) are considered to be potentially carcinogenic. Phosphorus in the PO(4) form is of concern because it causes eutrophication of surface water bodies. The effect of grazing animals on soil and water quality must be evaluated at both the field and watershed scales. Such evaluation must account for both direct input of animal wastes from the grazing animal and also applications of inorganic fertilizers to produce quality pastures. Watershed-scale studies have primarily used the approach of nutrient loadings per land area and nutrient removals as livestock harvests. A number of studies have measured nutrient loads in surface runoff from grazed land and compared loads with other land uses, including row crop agriculture and forestry. Concentrations in discharge have been regressed against standard grazing animal units per land area. Watersheds with concentrated livestock populations have been shown to discharge as much as 5 to 10 times more nutrients than watersheds in cropland or forestry. The other major water quality concern with grazing animals is pathogens, which may move

  3. Effect of fertility on the economics of pasture-based dairy systems.

    PubMed

    Shalloo, L; Cromie, A; McHugh, N

    2014-05-01

    There are significant costs associated with reproductive inefficiency in pasture-based dairy herds. This study has quantified the economic effect of a number of key variables associated with reproductive inefficiency in a dairy herd and related them to 6-week calving rate for both cows and heifers. These variables include: increased culling costs, the effects of sub optimum calving dates, increased labour costs and increased artificial insemination (AI) and intervention costs. The Moorepark Dairy Systems Model which is a stochastic budgetary simulation model was used to simulate the overall economic effect at farm level. The effect of change in each of the components was simulated in the model and the costs associated with each component was quantified. An analysis of national data across a 4-year period using the Irish Cattle Breeding Federation database was used to quantify the relationship between the 6-week calving rate of a herd with survivability (%), calving interval (days) and the level of AI usage. The costs associated with increased culling (%), calving date slippage (day), increased AI and intervention costs (0.1 additional inseminations), as well as, increased labour costs (10%) were quantified as €13.68, €3.86, €4.56 and €29.6/cow per year. There was a statistically significant association between the 6-week calving rate and survivability, calving interval and AI usage at farm level. A 1% change in 6-week calving rate was associated with €9.26/cow per annum for cows and €3.51/heifer per annum for heifers. This study does not include the indirect costs such as reduced potential for expansion, increased costs associated with failing to maintain a closed herd as well as the unrealised potential within the herd. PMID:24679449

  4. Effect of fertility on the economics of pasture-based dairy systems.

    PubMed

    Shalloo, L; Cromie, A; McHugh, N

    2014-05-01

    There are significant costs associated with reproductive inefficiency in pasture-based dairy herds. This study has quantified the economic effect of a number of key variables associated with reproductive inefficiency in a dairy herd and related them to 6-week calving rate for both cows and heifers. These variables include: increased culling costs, the effects of sub optimum calving dates, increased labour costs and increased artificial insemination (AI) and intervention costs. The Moorepark Dairy Systems Model which is a stochastic budgetary simulation model was used to simulate the overall economic effect at farm level. The effect of change in each of the components was simulated in the model and the costs associated with each component was quantified. An analysis of national data across a 4-year period using the Irish Cattle Breeding Federation database was used to quantify the relationship between the 6-week calving rate of a herd with survivability (%), calving interval (days) and the level of AI usage. The costs associated with increased culling (%), calving date slippage (day), increased AI and intervention costs (0.1 additional inseminations), as well as, increased labour costs (10%) were quantified as €13.68, €3.86, €4.56 and €29.6/cow per year. There was a statistically significant association between the 6-week calving rate and survivability, calving interval and AI usage at farm level. A 1% change in 6-week calving rate was associated with €9.26/cow per annum for cows and €3.51/heifer per annum for heifers. This study does not include the indirect costs such as reduced potential for expansion, increased costs associated with failing to maintain a closed herd as well as the unrealised potential within the herd.

  5. Effect of soil type and fertilization level on mineral concentration of pasture: potential relationships to ruminant performance and health.

    PubMed

    Soder, K J; Stout, W L

    2003-06-01

    A three-year study was conducted to measure the effects of varying levels of dairy slurry application on mineral concentration of forages from three soils types. Slurry was applied to orchardgrass (Dactylis glomerata [L.] cv. Pennlate) growing in 60-cm diameter drainage lysimeters to measure the effect of four levels of slurry (urine and feces) N application (0, 168, 336, and 672 kg of N.ha-1.yr-1) on mineral (P, K, Ca, Mg) concentration of the forage on three soil types (Hagerstown, Hartleton, and Rayne). The results were then related to potential effects on performance and health of grazing ruminants. Forage P was not affected by slurry application (mean = 0.46% of DM). Forage grown on the Hartleton soil had the highest (P < 0.05) P concentration (0.6% of DM). Forage K increased (P < 0.05) with increased slurry (2.50, 2.85, 3.22, and 3.45% of DM, respectively), and was lowest (P < 0.05) for forage grown on the Rayne soil (2.69% of DM). Forage Ca decreased (P < 0.05) with increased slurry (0.59, 0.56, 0.50, and 0.49% of DM, respectively) and was not affected by soil type. Forage Mg also decreased (P < 0.05) with increased slurry (0.25, 0.24, 0.24, and 0.23% of DM, respectively), and was highest (P < 0.05) for the Hartleton soil (0.27% of DM). The variable results in mineral concentration associated with soil type may have, in part, been due to prior soil fertility. The P and Mg concentrations in all treatments were generally adequate for grazing ruminants. The K concentrations were high in relation to NRC recommendations for prepartum dairy cows, which might predispose them to milk fever. The Ca concentrations were inadequate for lactating dairy cows. Comprehensive forage testing and diet formulation based on individual farm situations is the best strategy to ensure proper mineral nutrition of grazing animals.

  6. Restricting daily time at pasture at low and high pasture allowance: effects on pasture intake and behavioral adaptation of lactating dairy cows.

    PubMed

    Pérez-Ramírez, E; Peyraud, J L; Delagarde, R

    2009-07-01

    In pasture-based dairy systems, daily time at pasture is restricted during several periods of the year. The aim of this experiment was to evaluate the effect of restricting time at pasture on milk yield, pasture dry matter (DM) intake, and grazing behavior of dairy cows according to pasture allowance (PA), which partly defines pasture availability. The experiment was carried out in spring on strip-grazed perennial ryegrass pastures. The 6 treatments consisted of 3 durations of daily time at pasture [U: unrestricted day and night grazing (22 h at pasture); R9: 1 grazing session restricted to 9 h between the 2 milkings; R5: 2 grazing sessions of 2.75 h after each milking) compared at low and high PA (13 and 24 kg of DM/d per cow >5 cm, respectively). Eighteen mid-lactation Holstein dairy cows were used according to a 6 x 4 incomplete Latin square design replicated 3 times with four 14-d periods. Pasture DM intake was measured by the ytterbium-fecal index method and grazing behavior from portable devices. On average, restricting time at pasture from U to R (mean of R5 + R9) decreased pasture intake by 2.9 kg of DM, milk yield by 1.3 kg, and milk protein concentration by 0.11%, and increased milk fat concentration by 0.20%. Pasture intake and milk yield did not differ significantly between R9 and R5. The reduction of pasture intake and milk yield with decreasing time at pasture was greater at high compared with low PA. Grazing times were 536, 414, and 305 min, representing proportions of time spent grazing of 0.40, 0.77, and 0.93 for treatments U, R9, and R5, respectively. The reduction of grazing time with decreasing time at pasture was greater at high compared with low PA. Pasture intake rate greatly increased with decreasing time at pasture, but mainly on R5 (29.8, 31.6, and 42.1 g of DM/min for U, R9, and R5, respectively). The effect of time at pasture on pasture intake rate was unaffected by PA. In conclusion, the effect of restriction of time at pasture on

  7. Treatment with a nonsteroidal antiinflammatory drug after calving did not improve milk production, health, or reproduction parameters in pasture-grazed dairy cows.

    PubMed

    Meier, S; Priest, N V; Burke, C R; Kay, J K; McDougall, S; Mitchell, M D; Walker, C G; Heiser, A; Loor, J J; Roche, J R

    2014-05-01

    Previous research results have indicated an increase in pregnancy rate in pasture-grazed cows treated with a nonsteroidal antiinflammatory drug (NSAID) 3 to 4 wk postcalving, when a high proportion of nucleated cells from within the uterus were polymorphonucleated; however, no effect on milk production was detected. It was hypothesized that this lack of effect on milk production was because the administration of the NSAID was too late after calving. The aims of the current study were to evaluate the timing of administering a propionic acid-derived NSAID (i.e., carprofen) on milk production, metabolic status, uterine health, and reproductive performance. Six-hundred and thirty-nine cows (134 primiparous and 505 multiparous) calving between July 4 and September 5, 2012, in 2 herds (herd 1: n=228; herd 2: n=411) were enrolled. Using a randomized block design, cows were allocated to 1 of 3 treatment groups as they calved: (1) no treatment (control; n=221), (2) NSAID administered on d 1, 3, and 5 postcalving (early; n=214), and (3) NSAID administered on d 19, 21, and 23 postcalving (late; n=204). Milk production and composition, and body condition were determined weekly. Blood was sampled at 4 time points (1 precalving and 3 postcalving) to determine the effects of treatment on indicators of metabolic health and energy status. Uterine health was determined by measuring the proportion of nucleated cells that were polymorphonucleated following cytobrush sampling of the uterus between d 13 to 24 and d 30 to 49 postcalving. Irrespective of timing of application, NSAID did not affect milk production, body weight, or body condition during early lactation. Treatment with an NSAID 19 to 23 d postcalving increased the proportion of cows submitted for breeding during the first 3 wk of the seasonal breeding program (control: 85%, early: 83%, and late: 92%), but did not affect conception or pregnancy rates. No detectable effect of treatment on uterine health or circulating

  8. The Effects of Steroid Implant and Dietary Soybean Hulls on Estrogenic Activity of Sera of Steers Grazing Toxic Endophyte-Infected Tall Fescue Pasture

    PubMed Central

    Shappell, Nancy W.; Flythe, Michael D.; Aiken, Glen E.

    2015-01-01

    Soybean hulls (SBHs) have been fed to cattle pasturing on endophyte-infected tall fescue in attempts to increase rate of gain. Literature reports indicated some symptoms associated with fescue toxicosis were ameliorated by the use of steroidal implants containing estradiol (E2) and progesterone [implantation (IMP)], feeding SBHs, or the combination of the two. While the mechanism for amelioration was unclear, the SBHs were postulated as acting as a diluent of the toxic factors of the fescue. Alternatively, estradiol and phytoestrogens of SBHs might be acting through relaxation of the persistent vasoconstriction found in animals ingesting ergot alkaloids of endophyte-infected fescue. If so, estrogenic activity of serum of steers receiving SBHs, IMP, or a combination of the two should be elevated. Using the cellular proliferation assay of estrogenicity (E-Screen), estradiol equivalents (E2Eqs) were determined on both SBHs and the serum of steers from a previously reported study. Range of SBHs was 5.0–8.5 ng Eqs g−1 DM (mean 6.5, n = 4 from different commercial sources of SBHs). At the rate fed, theoretically calculated blood E2Eq could be physiologically relevant (~80 pg mL−1, based on 2.3 kg SBHs d−1, 300 kg steer, 5.7% blood volume, and 10% absorption). Serum E2Eqs did increase in steers (P ≤ 0.05) with steroidal implants or fed SBHs by 56 and 151% over control, respectively, and treatments were additive (211% increase). Serum prolactin was also greatest for the SBH + IMP group (188 ng mL−1, P < 0.05), concentrations comparable to values reported for steers grazing endophyte-free fescue. Prolactin in the SBH group was higher than IMP or control groups (146 versus 76 and 60 ng mL−1, respectively). Still unknown is if additional E2Eqs from dietary phytoestrogens or exogenous sources of estradiol can further reduce symptoms of fescue toxicosis. The E-Screen assay was an effective tool in monitoring serum for estrogenic effects

  9. Nitrous oxide emissions and herbage accumulation in smooth bromegrass pastures with nitrogen fertilizer and ruminant urine application

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural soils contribute significantly to nitrous oxide (N2O) emissions, but little data is available on N2O emissions from smooth bromegrass (Bromus inermis Leyss.) pastures. This study evaluated soil N2O emissions and herbage accumulation from smooth bromegrass pasture in eastern Nebraska, US...

  10. Studies of pasture production in Extremadura (Spain)

    NASA Astrophysics Data System (ADS)

    Murillo Vilanova, M.; González López, F.; Paredes Galán, J.; Prieto Macías, P. M.; Blanco, V. Maya

    2009-04-01

    The region of Extremadura covers more than four million hectares in the South West of Spain, with dehesas occupying almost 1.5 million hectares of its surface. This agro-silvo-pastoral land use system constitutes the most recommendable model for extensive exploitation in Mediterranean areas in which the semiarid climate and the poor, shallow soils are constraints on any other type of agricultural use. It is characterized by a grassland with a disperse cover of oak trees and shrubs, where the main production is extensive livestock combined with agriculture and forestry. The pastures are the basis for animal breeding in the dehesas being these ecosystems of great economic, social as well as environmental value in the southwestern Iberian Peninsula. These facts justify the investigation on pasture improvement and the study on spatial and temporal variations of pasture production in the whole region. Pasture production is quite variable, highly determined by soil and climate conditions. Rainfall variability produces large seasonal and annual variations, with the highest production in spring, low production in autumn and very scarce in winter. During summer, while pastures are wilting, hard seeds stay latent in the soil and gradually germinate in consecutive months. But variability of pasture production in such a heterogeneous ecosystem does not only depend on edaphic and climate conditions, but also on other factors, such as grazing management, improvement measures, fertilization, exploitation infrastructures, stocking rates, etc. The present study, carried out in the framework of the "Montado/Dehesa" INTERREG project, aimed to sample pasture production in Extremadura, in order to provide a large amount of real data for determining the influence of the different factors involved, which will constitute the basis for the developement of a production model. The latter will be integrated into a tool helping to decide on the best practice of dehesa management. Pastures were

  11. Temperate grass response to timing of grazing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Grazing management has a significant impact on pasture growth. We determined how timing of grazing influences grass productivity, yield distribution, and persistence. Meadow fescue [Schedonorus pratensis (Huds.) P. Beauv.], orchardgrass (Dactylis glomerata L.), quackgrass [Elymus repens (L.) Gould...

  12. Thermal comfort and lactation yields of dairy cows grazed on farms in a pasture-based feed system in eastern New South Wales, Australia

    NASA Astrophysics Data System (ADS)

    Dragovich, D.

    1981-06-01

    A temperature-humidity index (THI) was used to associate varying degrees of “thermal comfort” for livestock with milk yields from dairy herds in eastern New South Wales. A pasture-based feed system was used on farms in the various environments occurring between 28°S and 37°S Lat. Low dairy cow productivity was registered in high-stress (high THI) areas, where the indirect effects of climate on pasture quality and availability compounded the direct stress on livestock; districts recording high lactation yields were located in low-stress areas, as anticipated by the biometeorological index. Fluctuations in lactation yields at THI values between the high and low stress areas were explained in terms of rainfall and temperature effects on pasture species and pasture growth patterns.

  13. Application of nitrogen from swine lagoon effluent to bermudagrass pastures: seasonal changes in forage nitrogenous constituents and effects of energy and escape protein supplementation on beef cattle performance.

    PubMed

    Rogers, J R; Harvey, R W; Poore, M H; Mueller, J P; Barker, J C

    1996-05-01

    A 2-yr study was conducted to evaluate 1) the effects of nitrogen level from swine lagoon effluent on forage composition and animal performance and 2) the effects of supplemental escape protein (EP) on performance by steers grazing pastures fertilized with swine lagoon effluent. Bermudagrass (Cynodon dactylon) pastures were fertilized via sprinkler irrigation with either 448 or 896 kg/ha of N from swine lagoon effluent (two pasture replications/treatment). Within each pasture, four supplement treatments were evaluated using electronic Calan gates (8 steers.pasture-1.yr-1). The treatments were 1) negative control (pasture only); 2) energy control, which supplied 79.9 g of EP.hd-1.d-1; 3) 159 g of EP.hd-1.d-1, and 4) 239 g of EP.hd-1.d-1. Gains were increased (P < .05) an average of .15 kg/d by supplementation, with no differences in gain among supplements. Forage samples representative of that grazed by steers (CONSUM) and representative of all available forage (AVAIL) were obtained at 14-d intervals. Total CP content of CONSUM and AVAIL samples were slightly higher (P < .20 and P < .15, respectively) from pastures fertilized with 896 compared with 448 kg/ha of N (20.8 vs 20.0% for CONSUM and 15.2 vs 14.2% for AVAIL). Concentrations of nonprotein N and soluble true protein (% of CP) in both AVAIL and CONSUM samples were higher (P < .06) from pastures fertilized with the higher N level. Total N uptake by the plant, based on CP content and animal grazing days/ha, was essentially the same for both N treatments. PMID:8726746

  14. The effects of steroid implant and dietary soybean hulls on estrogenic activity of sera of steers grazing toxic endophyte-infected tall fescue pasture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean hulls (SBHs), a co-product of soybean meal milling, have been fed to cattle pasturing on endophyte-infected tall fescue in attempts to increase rate of gain. Literature reports indicated some symptoms associated with fescue toxicosis were ameliorated by the use of steroidal implants contain...

  15. Response of a southeastern U.S. bahiagrass pasture to elevated atmospheric CO2 and N fertilization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the Southeastern US both managed and unmanaged pasture systems remain understudied agro-ecosystems in terms of the effects of elevated atmospheric CO2 concentration. Therefore, we initiated a long-term study of bahiagrass (Paspalum notatum Flüggé) response to elevated CO2 using open top field cha...

  16. Effects of elevated atmospheric CO2 and N fertilization on bahiagrass pastures in the Southeastern U.S.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of elevated atmospheric CO2 on pasture systems remain understudied in the Southeastern US. A 10-year study of bahiagrass (Paspalum notatum Flüggé) response to elevated CO2 was established in 2005 using open top field chambers on a Blanton loamy sand (loamy siliceous, thermic, Grossarenic...

  17. Hypoglycin A Content in Blood and Urine Discriminates Horses with Atypical Myopathy from Clinically Normal Horses Grazing on the Same Pasture.

    PubMed

    Bochnia, M; Ziegler, J; Sander, J; Uhlig, A; Schaefer, S; Vollstedt, S; Glatter, M; Abel, S; Recknagel, S; Schusser, G F; Wensch-Dorendorf, M; Zeyner, A

    2015-01-01

    Hypoglycin A (HGA) in seeds of Acer spp. is suspected to cause seasonal pasture myopathy in North America and equine atypical myopathy (AM) in Europe, fatal diseases in horses on pasture. In previous studies, this suspicion was substantiated by the correlation of seed HGA content with the concentrations of toxic metabolites in urine and serum (MCPA-conjugates) of affected horses. However, seed sampling was conducted after rather than during an outbreak of the disease. The aim of this study was to further confirm the causality between HGA occurrence and disease outbreak by seed sampling during an outbreak and the determination of i) HGA in seeds and of ii) HGA and MCPA-conjugates in urine and serum of diseased horses. Furthermore, cograzing healthy horses, which were present on AM affected pastures, were also investigated. AM-pastures in Germany were visited to identify seeds of Acer pseudoplatanus and serum (n = 8) as well as urine (n = 6) from a total of 16 diseased horses were analyzed for amino acid composition by LC-ESI-MS/MS, with a special focus on the content of HGA. Additionally, the content of its toxic metabolite was measured in its conjugated form in body fluids (UPLC-MS/MS). The seeds contained 1.7-319.8 μg HGA/g seed. The content of HGA in serum of affected horses ranged from 387.8-8493.8 μg/L (controls < 10 μg/L), and in urine from 143.8-926.4 μg/L (controls < 10 μg/L), respectively. Healthy cograzing horses on AM-pastures showed higher serum (108.8 ± 83.76 μg/L) and urine concentrations (26.9 ± 7.39 μg/L) compared to control horses, but lower concentrations compared to diseased horses. The range of MCPA-carnitine and creatinine concentrations found in diseased horses in serum and urine were 0.17-0.65 mmol/L (controls < 0.01), and 0.34-2.05 μmol/mmoL (controls < 0.001), respectively. MCPA-glycine levels in urine of cograzing horses were higher compared to controls. Thus, the causal link between HGA intoxication and disease outbreak could be

  18. Hypoglycin A Content in Blood and Urine Discriminates Horses with Atypical Myopathy from Clinically Normal Horses Grazing on the Same Pasture

    PubMed Central

    Bochnia, M.; Ziegler, J.; Sander, J.; Uhlig, A.; Schaefer, S.; Vollstedt, S.; Glatter, M.; Abel, S.; Recknagel, S.; Schusser, G. F.; Wensch-Dorendorf, M.; Zeyner, A.

    2015-01-01

    Hypoglycin A (HGA) in seeds of Acer spp. is suspected to cause seasonal pasture myopathy in North America and equine atypical myopathy (AM) in Europe, fatal diseases in horses on pasture. In previous studies, this suspicion was substantiated by the correlation of seed HGA content with the concentrations of toxic metabolites in urine and serum (MCPA-conjugates) of affected horses. However, seed sampling was conducted after rather than during an outbreak of the disease. The aim of this study was to further confirm the causality between HGA occurrence and disease outbreak by seed sampling during an outbreak and the determination of i) HGA in seeds and of ii) HGA and MCPA-conjugates in urine and serum of diseased horses. Furthermore, cograzing healthy horses, which were present on AM affected pastures, were also investigated. AM-pastures in Germany were visited to identify seeds of Acer pseudoplatanus and serum (n = 8) as well as urine (n = 6) from a total of 16 diseased horses were analyzed for amino acid composition by LC-ESI-MS/MS, with a special focus on the content of HGA. Additionally, the content of its toxic metabolite was measured in its conjugated form in body fluids (UPLC-MS/MS). The seeds contained 1.7–319.8 μg HGA/g seed. The content of HGA in serum of affected horses ranged from 387.8–8493.8 μg/L (controls < 10 μg/L), and in urine from 143.8–926.4 μg/L (controls < 10 μg/L), respectively. Healthy cograzing horses on AM-pastures showed higher serum (108.8 ± 83.76 μg/L) and urine concentrations (26.9 ± 7.39 μg/L) compared to control horses, but lower concentrations compared to diseased horses. The range of MCPA-carnitine and creatinine concentrations found in diseased horses in serum and urine were 0.17–0.65 mmol/L (controls < 0.01), and 0.34–2.05 μmol/mmoL (controls < 0.001), respectively. MCPA-glycine levels in urine of cograzing horses were higher compared to controls. Thus, the causal link between HGA intoxication and disease outbreak

  19. Hypoglycin A Content in Blood and Urine Discriminates Horses with Atypical Myopathy from Clinically Normal Horses Grazing on the Same Pasture.

    PubMed

    Bochnia, M; Ziegler, J; Sander, J; Uhlig, A; Schaefer, S; Vollstedt, S; Glatter, M; Abel, S; Recknagel, S; Schusser, G F; Wensch-Dorendorf, M; Zeyner, A

    2015-01-01

    Hypoglycin A (HGA) in seeds of Acer spp. is suspected to cause seasonal pasture myopathy in North America and equine atypical myopathy (AM) in Europe, fatal diseases in horses on pasture. In previous studies, this suspicion was substantiated by the correlation of seed HGA content with the concentrations of toxic metabolites in urine and serum (MCPA-conjugates) of affected horses. However, seed sampling was conducted after rather than during an outbreak of the disease. The aim of this study was to further confirm the causality between HGA occurrence and disease outbreak by seed sampling during an outbreak and the determination of i) HGA in seeds and of ii) HGA and MCPA-conjugates in urine and serum of diseased horses. Furthermore, cograzing healthy horses, which were present on AM affected pastures, were also investigated. AM-pastures in Germany were visited to identify seeds of Acer pseudoplatanus and serum (n = 8) as well as urine (n = 6) from a total of 16 diseased horses were analyzed for amino acid composition by LC-ESI-MS/MS, with a special focus on the content of HGA. Additionally, the content of its toxic metabolite was measured in its conjugated form in body fluids (UPLC-MS/MS). The seeds contained 1.7-319.8 μg HGA/g seed. The content of HGA in serum of affected horses ranged from 387.8-8493.8 μg/L (controls < 10 μg/L), and in urine from 143.8-926.4 μg/L (controls < 10 μg/L), respectively. Healthy cograzing horses on AM-pastures showed higher serum (108.8 ± 83.76 μg/L) and urine concentrations (26.9 ± 7.39 μg/L) compared to control horses, but lower concentrations compared to diseased horses. The range of MCPA-carnitine and creatinine concentrations found in diseased horses in serum and urine were 0.17-0.65 mmol/L (controls < 0.01), and 0.34-2.05 μmol/mmoL (controls < 0.001), respectively. MCPA-glycine levels in urine of cograzing horses were higher compared to controls. Thus, the causal link between HGA intoxication and disease outbreak could be

  20. Inputs and losses by surface runoff and subsurface leaching for pastures managed by continuous or rotational stocking.

    PubMed

    Owens, L B; Barker, D J; Loerch, S C; Shipitalo, M J; Bonta, J V; Sulc, R M

    2012-01-01

    Pasture management practices can affect forage quality and production, animal health and production, and surface and groundwater quality. In a 5-yr study conducted at the North Appalachian Experimental Watershed near Coshocton, Ohio, we compared the effects of two contrasting grazing methods on surface and subsurface water quantity and quality. Four pastures, each including a small, instrumented watershed (0.51-1.09 ha) for surface runoff measurements and a developed spring for subsurface flow collection, received 112 kg N ha(-1) yr(-1) and were grazed at similar stocking rates (1.8-1.9 cows ha(-1)). Two pastures were continuously stocked; two were subdivided so that they were grazed with frequent rotational stocking (5-6 times weekly). In the preceding 5 yr, these pastures received 112 kg N ha(-1) yr(-1) after several years of 0 N fertilizer and were grazed with weekly rotational stocking. Surface runoff losses of N were minimal. During these two periods, some years had precipitation up to 50% greater than the long-term average, which increased subsurface flow and NO(3)-N transport. Average annual NO(3)-N transported in subsurface flow from the four watersheds during the two 5-yr periods ranged from 11.3 to 22.7 kg N ha(-1), which was similar to or less than the mineral-N received in precipitation. Flow and transport variations were greater among seasons than among watersheds. Flow-weighted seasonal NO(3)-N concentrations in subsurface flow did not exceed 7 mg L(-1). Variations in NO(3)-N leached from pastures were primarily due to variable precipitation rather than the effects of continuous, weekly rotational, or frequent rotational stocking practices. This suggests that there was no difference among these grazing practices in terms of NO(3)-N leaching. PMID:22218179

  1. National-Scale Changes in Soil Profile C and N in New Zealand Pastures are Determined by Land Use

    NASA Astrophysics Data System (ADS)

    Schipper, L. A.; Parfitt, R.; Ross, C.; Baisden, W. T.; Claydon, J.; Fraser, S.

    2010-12-01

    Grazed pasture is New Zealand’s predominant agricultural land-use and has been relatively recently developed from forest and native grasslands/shrub communities. From the 1850s onwards, land was cleared and exotic pastures established. Phosphorus fertilizer was increasingly used after 1950 which accelerated N fixation by clover. In the last two decades N fertilizers have been used, and grazing intensity has increased, thus affecting soil C and N. Re-sampling of 31 New Zealand soil profiles under grazed pasture measured surprisingly large losses of C and N over the last 2-3 decades (Schipper et al., 2007 Global Change Biology 13:1138-1144). These profiles were predominantly on the most intensively grazed flat land. We extended this re-sampling to 83 profiles (to 90 cm depth), to investigate whether changes in soil C and N stocks also occurred in less intensively managed pasture. Archived soils samples were analysed for total soil C and N alongside the newly collected samples. Intact cores were collected to determine bulk density through the profile. Over an average of 27 years, soils (0-30 cm) in flat dairy pastures significantly lost 0.73±0.16 Mg C ha-1y-1 and 57±16 kg N ha-1y-1 while we observed no change in soil C or N in flat pasture grazed by “dry stock” (e.g., sheep, beef), or in grazed tussock grasslands. Grazed hill country soils (0-30 cm) gained 0.52±0.18 Mg C ha-1y-1 and 66±18 kg N ha-1y-1. The losses of C and N were strongly correlated and C:N ratio has generally declined suggesting soils are becoming N saturated. Losses and gains also occurred in soil layers below 30 cm demonstrating that organic matter throughout the profile was responding to land use. The losses under dairying may be due to greater grazing pressure, fertilizer inputs and exports of C and N. There is evidence that grazing pressure reduces inputs of C below ground, reduces soil microbial C, and that dairy cow urine can mobilise C and N. Gains in hill country pastures may be due

  2. Sequestration of carbon and phosphorus in subtropical grazed historically isolated wetlands

    NASA Astrophysics Data System (ADS)

    Mitchell, J. D.; Jawitz, J. W.

    2009-12-01

    Hydrologic restoration of ditched and drained wetlands within the 12000 km2 Lake Okeechobee basin (LOB), FL is expected to promote carbon (C) accretion and phosphorus (P) retention. The majority of P loading to Lake Okeechobee is attributed to historical pasture fertilization and continued high density cattle activity which perpetuate elevated P transport to the lake from dairies and cow/calf operations. Isolated wetlands which dominate the LOB landscape have been historically ditched to increase pasture area for grazing. Current best management practices intended to reduce P transport to the lake include the option of fencing wetlands in cattle pastures to prevent cattle access. The objective of this study was to develop a predictive model of the dynamics of wetland biomass, soil accretion, C and P. The coupled effects of grazing intensity, highly transient water level, and seasonality were incorporated. The model was conditioned based on approximately three years of monitoring data from four isolated wetlands in the LOB. Drought-induced declining water table resulted in decreased wetland plant biomass in both grazed and ungrazed simulations but reduction was more severe in the grazed simulations. High intensity grazing during flooded conditions resulted in declines in wetland plant biomass due to disconnection between leaves and the air column. Standing biomass and C and P storage in vegetation increased with the exclusion of grazing in these wetlands. Although vegetation nutrient storage is short term, biomass turnover supports accretion of soil and associated C and P. Predicted implications for C and P sequestration at the watershed scale and reduction of P load to the lake are directly related to the wetland area that can be excluded from grazing.

  3. Reduction of phosphorus concentration in mineral supplement on fertility rate, maternal ability and costs of beef cows reared in pastures of Urochloa decumbens.

    PubMed

    Costa, Rogério Magnoli; Ponsano, Elisa Helena Giglio; de Souza, Vinícius Carneiro; Malafaia, Pedro

    2016-02-01

    Manufacturing and marketing of mineral mixtures with less than 40 g kg(-1) phosphorus (P) is prohibited under Brazilian regulations, although scientific evidence rejects this recommendation. Considering the hypothesis that P levels in commercial mineral supplements can be reduced without affecting animal performance and health, the objective of this experiment was to evaluate the effects of reducing the concentration of P in the mineral supplement (from 40 to 18 g kg(-1)) of a herd of beef cows grazing tropical pastures of signal grass (Urochloa decumbens). The experiment was carried out in the savanna region of Mato Grosso do Sul, Brazil, during the years 2011 to 2013. Variables analyzed included pregnancy rate, calving interval, weight of calves at weaning, and cost of mineral supplementation. There were no changes in the reproductive parameters of the herd and the weight at weaning of the calves. However, the cost of mineral supplementation was significantly lower when the herd was supplemented with the mineral mix containing only 18 g kg(-1) P. Phosphorus concentration of the forage was analyzed monthly during 1 year and averaged 1.9 ± 0.45 g kg(-1) DM. Thus, it appears possible to reduce P content and cost of mineral supplementation without any adverse effects on the health and productivity of beef cattle herds in the State of Mato Grosso do Sul. However, the final decision should be made based on the clinical-nutritional examination and by constant technical assistance to the farm.

  4. Reduction of phosphorus concentration in mineral supplement on fertility rate, maternal ability and costs of beef cows reared in pastures of Urochloa decumbens.

    PubMed

    Costa, Rogério Magnoli; Ponsano, Elisa Helena Giglio; de Souza, Vinícius Carneiro; Malafaia, Pedro

    2016-02-01

    Manufacturing and marketing of mineral mixtures with less than 40 g kg(-1) phosphorus (P) is prohibited under Brazilian regulations, although scientific evidence rejects this recommendation. Considering the hypothesis that P levels in commercial mineral supplements can be reduced without affecting animal performance and health, the objective of this experiment was to evaluate the effects of reducing the concentration of P in the mineral supplement (from 40 to 18 g kg(-1)) of a herd of beef cows grazing tropical pastures of signal grass (Urochloa decumbens). The experiment was carried out in the savanna region of Mato Grosso do Sul, Brazil, during the years 2011 to 2013. Variables analyzed included pregnancy rate, calving interval, weight of calves at weaning, and cost of mineral supplementation. There were no changes in the reproductive parameters of the herd and the weight at weaning of the calves. However, the cost of mineral supplementation was significantly lower when the herd was supplemented with the mineral mix containing only 18 g kg(-1) P. Phosphorus concentration of the forage was analyzed monthly during 1 year and averaged 1.9 ± 0.45 g kg(-1) DM. Thus, it appears possible to reduce P content and cost of mineral supplementation without any adverse effects on the health and productivity of beef cattle herds in the State of Mato Grosso do Sul. However, the final decision should be made based on the clinical-nutritional examination and by constant technical assistance to the farm. PMID:26685846

  5. From the lab bench: A systematic approach to grazing cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A column was written to discuss the use of grazing systems to overcome challenges of managing grazed pastures. Kentucky cattlemen must manage around summer slumps in growth of cool-season perennial grasses, periodic drought, and cattle markets that do not always cooperate with pasture growth patter...

  6. Effect of nitrogen fertilization rate and regrowth interval of grass herbage on methane emission of zero-grazing lactating dairy cows.

    PubMed

    Warner, D; Podesta, S C; Hatew, B; Klop, G; van Laar, H; Bannink, A; Dijkstra, J

    2015-05-01

    emission, but effects of N fertilization were generally most distinct with GH of 5 wk regrowth. The present results suggest that altering grass quality through an increase of N fertilization and a shorter regrowth interval can reduce CH4 emission in zero-grazing dairy cows, depending on the unit in which it is expressed. The larger amount of CH4 produced per day and cow with the more intensively managed GH is compensated by a higher feed digestibility and FPCM yield.

  7. Pasture Management Strategies for Sequestering Soil Carbon - Final Report

    SciTech Connect

    Franzluebbers, Alan J.

    2006-03-15

    Pasturelands account for 51 of the 212 Mha of privately held grazing land in the USA. Tall fescue is the most important cool-season perennial forage for many beef cattle producers in the humid region of the USA. A fungal endophyte, Neotyphodium coenophialum, infects the majority of tall fescue stands with a mutualistic association. Ergot alkaloids produced by the endophyte have negative impacts on cattle performance. However, there are indications that endophyte infection of tall fescue is a necessary component of productive and persistent pasture ecology. The objectives of this research were to characterize and quantify changes in soil organic carbon and associated soil properties under tall fescue pastures with and without endophyte infection of grass. Pastures with high endophyte infection had greater concentration of soil organic carbon, but lower concentration of biologically active soil carbon than pastures with low endophyte infection. A controlled experiment suggested that endophyte-infected leaf tissue may directly inhibit the activity of soil microorganisms. Carbon forms of soil organic matter were negatively affected and nitrogen forms were positively affected by endophyte addition to soil. The chemical compounds in endophyte-infected tall fescue (ergot alkaloids) that are responsible for animal health disorders were found in soil, suggesting that these chemicals might be persistent in the environment. Future research is needed to determine whether ergot alkaloids or some other chemicals are responsible for increases in soil organic matter. Scientists will be able to use this information to better understand the ecological impacts of animals grazing tall fescue, and possibly to identify and cultivate other similar associations for improving soil organic matter storage. Another experiment suggested that both dry matter production and soil microbial activity could be affected by the endophyte. Sampling of the cumulative effects of 20 years of tall fescue

  8. Open pasture, silvopasture, and sward herbage maturity effects on nutritive value and fermentation characteristics of cool-season pasture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In Appalachian USA, growing forages within woodlots offers promise of increased farm productivity. A synchronized, temporal understanding of open (OP) and silvopasture (SP) nutritive characteristics is essential for grazing system development. We examined pasture type nutritive value relationships w...

  9. Dietary selection by domestic grazing ruminants: Current state of knowledge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ruminants grazing biodiverse pasture face many choices, including when and where to graze and how much herbage to consume. Scientific research has led to considerable knowledge about some of these choices (e.g. herbage DMI), but other aspects of the complex decision-making process of a grazing rumin...

  10. Evaluating Attitudes towards Changes in Rural Landscape by Grazing Cattle on Abandoned Paddy Fields

    NASA Astrophysics Data System (ADS)

    Yasuhito, Kitai; Toshihiro, Hattori; Hiroshi, Takahashi

    The appearance of cattle grazing abandoned paddy fields can be used to evaluate attitudes towards this land-use change. The semantic differential (SD) method was used families of a university student to evaluate and compare attitudes towards five types of rural landscape: pasture, pasture grazed by cattle, rice paddy field, abandoned paddy field converted to pasture and abandoned paddy field converted to pasture grazed by cattle. Cattle grazing abandoned paddy fields were determined to have a positive effect on the landscape. However, all grazing cattle created a negative attitude because of the unclean appearance of the landscape. Grazing cattle at high stocking rates in small areas could create a negative attitude because of the oppressive appearance of the landscape. The acceptance of grazing cattle was lower if the animals ware newly introduced to the landscape.

  11. Winter-annual pasture as a supplement for beef cows.

    PubMed

    Gunter, S A; Cassida, K A; Beck, P A; Phillips, J M

    2002-05-01

    In each of two experiments, 120 pregnant beef cows were stratified by body condition score, BW, breed, and age, randomly divided into six groups of 20, and assigned to one of six 5.1-ha bermudagrass (Cynodon dactylon [L.] Pers.) pastures (two replicates/ treatment) in early January to evaluate the use of winter-annual pasture as a supplement. All cows in Exp. 1 and 2 had ad libitum access to bermudagrass/dallisgrass (Paspalum dilatatum Poir.) hay plus three treatments: 1) a concentrate-based supplement fed 3 d/wk, 2) limit grazing on winter-annual pasture 2 d/wk (7 hr/ d; 0.04 ha x cow(-1) x grazing d(-1)), or 3) limit grazing on winter-annual pasture 3 d/wk (7 hr/d; 0.04 ha x cow(-1) x grazing d(-1)) sod-seeded into a portion of the pasture until mid-May. The seeded portion of pastures in Exp. 1 was planted with a mixture of wheat (Triticum aestivum L.) and rye (Secale cereale L.), but annual ryegrass (Lolium multiflorum Lam.) was added to the seed mixture in Exp. 2. In mid-May, cows were blocked by treatment and the previous sorting factors, randomly assigned to six new groups of 20, and placed on the six perennial pastures until calves were weaned. Groups of cows were exposed to a bull for 60 d beginning in mid-May. In Exp. 1 and 2, limit-grazing winter-annual pasture compared to the concentrate-based supplement or limit grazing 2 vs 3 d/wk did not affect (P > 0.15) cow BW. In Exp. 1, cows limit grazed on winter-annual pasture had a lower (P = 0.05) body condition score than cows fed the concentrate-based supplement in the early spring. However, in Exp. 2, cows limit grazed on winter-annual pasture had higher (P < or = 0.07) body condition score than cows fed the concentrate-based supplement. The conception rate of cows in Exp. 1 and 2 did not differ (P > 0.22) between cows fed concentrate-based supplements and cows limit grazed on winter-annual pasture. In Exp. 2, cows limit grazed 2 d/wk tended to have a greater (P = 0.10) conception rate than cows limit

  12. Carbon flux assessment in cow-calf grazing systems.

    PubMed

    Chiavegato, M B; Rowntree, J E; Powers, W J

    2015-08-01

    Greenhouse gas (GHG) fluxes and soil organic carbon (SOC) accumulation in grassland ecosystems are intimately linked to grazing management. This study assessed the carbon equivalent flux (Ceq) from 1) an irrigated, heavily stocked, low-density grazing system, 2) a nonirrigated, lightly stocked, high-density grazing system, and 3) a grazing-exclusion pasture site on the basis of the GHG emissions from pasture soils and enteric methane emissions from cows grazing different pasture treatments. Soil organic carbon and total soil nitrogen stocks were measured but not included in Ceq determination because of study duration and time needed to observe a change in soil composition. Light- and heavy-stocking systems had 36% and 43% greater Ceq than nongrazed pasture sites, respectively ( < 0.01). The largest contributor to increased Ceq from grazing systems was enteric CH emissions, which represented 15% and 32% of the overall emissions for lightly and heavily stocked grazing systems, respectively. Across years, grazing systems also had increased nitrous oxide (N2O; < 0.01) and CH emissions from pasture soils ( < 0.01) compared with nongrazed pasture sites but, overall, minimally contributed to total emissions. Results indicate no clear difference in Ceqflux between the grazing systems studied when SOC change is not incorporated ( = 0.11). A greater stocking rate potentially increased total SOC stock ( = 0.02), the addition of SOC deeper into the soil horizon ( = 0.01), and soil OM content to 30 cm ( < 0.01). The incorporation of long-term annual carbon sequestration into the determination of Ceq could change results and possibly differentiate the grazing systems studied. PMID:26440199

  13. Reproductive Performance of Holstein Dairy Cows Grazing in Dry-summer Subtropical Climatic Conditions: Effect of Heat Stress and Heat Shock on Meiotic Competence and In vitro Fertilization.

    PubMed

    Pavani, Krishna; Carvalhais, Isabel; Faheem, Marwa; Chaveiro, Antonio; Reis, Francisco Vieira; da Silva, Fernando Moreira

    2015-03-01

    The present study was designed to evaluate how environmental factors in a dry-summer subtropical climate in Terceira-Azores (situated in the North Atlantic Ocean: 38° 43' N 27° 12' W) can affect dairy cow (Holstein) fertility, as well as seasonal influence on in vitro oocytes maturation and embryos development. Impact of heat shock (HS) effects on in vitro oocyte's maturation and further embryo development after in vitro fertilization (IVF) was also evaluated. For such purpose the result of the first artificial insemination (AI) performed 60 to 90 days after calving of 6,300 cows were recorded for one year. In parallel, climatic data was obtained at different elevation points (n = 5) from 0 to 1,000 m and grazing points from 0 to 500 m, in Terceira island, and the temperature humidity index (THI) was calculated. For in vitro experiments, oocytes (n = 706) were collected weekly during all year, for meiotic maturation and IVF. Further, to evaluate HS effect, 891 oocytes were collected in the cold moths (December, January, February and March) and divided in three groups treated to HS for 24 h during in vitro maturation at: C (Control = 38.5°C), HS1 (39.5°C) and HS2 (40.5°C). Oocytes from each group were used for meiotic assessment and IVF. Cleavage, morula and blastocyst development were evaluated respectively on day 2, 6, and 9 after IVF. A negative correlation between cow's conception rate (CR) and THI in grazing points (-91.3%; p<0.001) was observed. Mean THI in warmer months (June, July, August and September) was 71.7±0.7 and the CR (40.2±1.5%) while in cold months THI was 62.8±0.2 and CR was 63.8±0.4%. A similar impact was obtained with in vitro results in which nuclear maturation rate (NMR) ranged from 78.4% (±8.0) to 44.3% (±8.1), while embryos development ranged from 53.8% (±5.8) to 36.3% (±3.3) in cold and warmer months respectively. In vitro HS results showed a significant decline (p<0.05) on NMR of oocytes for every 1°C rising temperature (78

  14. Reproductive Performance of Holstein Dairy Cows Grazing in Dry-summer Subtropical Climatic Conditions: Effect of Heat Stress and Heat Shock on Meiotic Competence and In vitro Fertilization

    PubMed Central

    Pavani, Krishna; Carvalhais, Isabel; Faheem, Marwa; Chaveiro, Antonio; Reis, Francisco Vieira; da Silva, Fernando Moreira

    2015-01-01

    The present study was designed to evaluate how environmental factors in a dry-summer subtropical climate in Terceira-Azores (situated in the North Atlantic Ocean: 38° 43′ N 27° 12′ W) can affect dairy cow (Holstein) fertility, as well as seasonal influence on in vitro oocytes maturation and embryos development. Impact of heat shock (HS) effects on in vitro oocyte’s maturation and further embryo development after in vitro fertilization (IVF) was also evaluated. For such purpose the result of the first artificial insemination (AI) performed 60 to 90 days after calving of 6,300 cows were recorded for one year. In parallel, climatic data was obtained at different elevation points (n = 5) from 0 to 1,000 m and grazing points from 0 to 500 m, in Terceira island, and the temperature humidity index (THI) was calculated. For in vitro experiments, oocytes (n = 706) were collected weekly during all year, for meiotic maturation and IVF. Further, to evaluate HS effect, 891 oocytes were collected in the cold moths (December, January, February and March) and divided in three groups treated to HS for 24 h during in vitro maturation at: C (Control = 38.5°C), HS1 (39.5°C) and HS2 (40.5°C). Oocytes from each group were used for meiotic assessment and IVF. Cleavage, morula and blastocyst development were evaluated respectively on day 2, 6, and 9 after IVF. A negative correlation between cow’s conception rate (CR) and THI in grazing points (−91.3%; p<0.001) was observed. Mean THI in warmer months (June, July, August and September) was 71.7±0.7 and the CR (40.2±1.5%) while in cold months THI was 62.8±0.2 and CR was 63.8±0.4%. A similar impact was obtained with in vitro results in which nuclear maturation rate (NMR) ranged from 78.4% (±8.0) to 44.3% (±8.1), while embryos development ranged from 53.8% (±5.8) to 36.3% (±3.3) in cold and warmer months respectively. In vitro HS results showed a significant decline (p<0.05) on NMR of oocytes for every 1°C rising

  15. Biodiversity on Swedish pastures: estimating biodiversity production costs.

    PubMed

    Nilsson, Fredrik Olof Laurentius

    2009-01-01

    This paper estimates the costs of producing biological diversity on Swedish permanent grasslands. A simple model is introduced where biodiversity on pastures is produced using grazing animals. On the pastures, the grazing animals create a sufficient grazing pressure to lead to an environment that suits many rare and red-listed species. Two types of pastures are investigated: semi-natural and cultivated. Biological diversity produced on a pasture is estimated by combining a biodiversity indicator, which measures the quality of the land, with the size of the pasture. Biodiversity is, in this context, a quantitative measure where a given quantity can be produced either by small area with high quality or a larger area with lower quality. Two areas in different parts of Sweden are investigated. Box-Cox transformations, which provide flexible functional forms, are used in the empirical analysis and the results indicate that the biodiversity production costs differ between the regions. The major contribution of this paper is that it develops and tests a method of estimating biodiversity production costs on permanent pastures when biodiversity quality differs between pastures. If the method were to be used with cost data, that were more thoroughly collected and covered additional production areas, biodiversity cost functions could be estimated and used in applied policy work. PMID:18079049

  16. Biodiversity on Swedish pastures: estimating biodiversity production costs.

    PubMed

    Nilsson, Fredrik Olof Laurentius

    2009-01-01

    This paper estimates the costs of producing biological diversity on Swedish permanent grasslands. A simple model is introduced where biodiversity on pastures is produced using grazing animals. On the pastures, the grazing animals create a sufficient grazing pressure to lead to an environment that suits many rare and red-listed species. Two types of pastures are investigated: semi-natural and cultivated. Biological diversity produced on a pasture is estimated by combining a biodiversity indicator, which measures the quality of the land, with the size of the pasture. Biodiversity is, in this context, a quantitative measure where a given quantity can be produced either by small area with high quality or a larger area with lower quality. Two areas in different parts of Sweden are investigated. Box-Cox transformations, which provide flexible functional forms, are used in the empirical analysis and the results indicate that the biodiversity production costs differ between the regions. The major contribution of this paper is that it develops and tests a method of estimating biodiversity production costs on permanent pastures when biodiversity quality differs between pastures. If the method were to be used with cost data, that were more thoroughly collected and covered additional production areas, biodiversity cost functions could be estimated and used in applied policy work.

  17. Managing variations in dairy cow nutrient supply under grazing.

    PubMed

    Peyraud, J L; Delagarde, R

    2013-03-01

    Grazed pasture, which is the cheapest source of nutrients for dairy cows, should form the basis of profitable and low-input animal production systems. Management of high-producing dairy cows at pasture is thus a major challenge in most countries. The objective of the present paper is to review the factors that can affect nutrient supply for grazing dairy cows in order to point out areas with scope for improvement on managing variations in nutrient supply to achieve high animal performance while maintaining efficient pasture utilisation per hectare (ha). Reviewing the range in animal requirements, intake capacity and pasture nutritive values shows that high-producing cows cannot satisfy their energy requirements from grazing alone and favourable to unfavourable situations for grazing dairy cows may be classified according to pasture quality and availability. Predictive models also enable calculation of supplementation levels required to meet energy requirements in all situations. Solutions to maintain acceptable level of production per cow and high output per ha are discussed. Strategies of concentrate supplementation and increasing use of legumes in mixed swards are the most promising. It is concluded that although high-producing cow cannot express their potential milk production at grazing, there is scope to improve animal performance at grazing given recent developments in our understanding of factors influencing forage intake and digestion of grazed forages.

  18. Performance of lactating dairy cows fed varying levels of total mixed ration and pasture.

    PubMed

    Vibart, Ronaldo E; Fellner, Vivek; Burns, Joseph C; Huntington, Gerald B; Green, James T

    2008-11-01

    Two, 8-week experiments, each using 30 lactating Holstein cows, were conducted to examine performance of animals offered combinations of total mixed ration (TMR) and high-quality pasture. Experiment 1 was initiated in mid October 2004 and Experiment 2 was initiated in late March 2005. Cows were assigned to either a 100% TMR diet (100:00, no access to pasture) or one of the following three formulated partial mixed rations (PMR) targeted at (1) 85% TMR and 15% pasture, (2) 70% TMR and 30% pasture and (3) 55% TMR and 45% pasture. Based on actual TMR and pasture intake, the dietary TMR and pasture proportions of the three PMR in Experiment 1 were 79% TMR and 21% pasture (79:21), 68% TMR and 32% pasture (68:32), and 59% TMR and 41% pasture (59:41), respectively. Corresponding proportions in Experiment 2 were 89% TMR and 11% pasture (89:11), 79% TMR and 21% pasture (79:21) and 65% TMR and 35% pasture (65:35), respectively. Reducing the proportion of TMR in the diets increased pasture consumption of cows on all PMR, but reduced total dry matter intake compared with cows on 100:00. An increase in forage from pasture increased the concentration of conjugated linoleic acids and decreased the concentration of saturated fatty acids in milk. Although milk and milk protein yields from cows grazing spring pastures (Experiment 2) increased with increasing intakes of TMR, a partial mixed ration that was composed of 41% pasture grazed in the fall (Experiment 1) resulted in a similar overall lactation performance with increased feed efficiency compared to an all-TMR ration. PMID:18701000

  19. Atypical myopathy in grazing horses: a first exploratory data analysis.

    PubMed

    Votion, Dominique-M; Linden, Annick; Delguste, Catherine; Amory, Hélène; Thiry, Etienne; Engels, Patrick; van Galen, Gaby; Navet, Rachel; Sluse, Francis; Serteyn, Didier; Saegerman, Claude

    2009-04-01

    Over the last decade, atypical myopathy (AM) in grazing horses has emerged in several European countries. An exploratory analysis was conducted to determine horse- and pasture-level indicators or factors associated with AM in Belgium. Belgian cases of AM confirmed by histology (n=57) were compared to their healthy co-grazing horses (n=77) and to pastured horses not involved with AM as controls (n=386). The pastures where confirmed cases were grazing (42 pastures; 38 sites; 44 incidences of AM) were compared with those of the controls (216 pastures; 96 sites; no incidence of AM). Statistically significant (P< or =0.05) exploratory variables, identified by means of adjusted odds ratios, suggested that indicators or factors associated with individual horses (young age, inactivity, body condition poor to normal), management practices (permanent pasturing, spreading of manure) and pasture characteristics (humid, sloping pastures, accumulated dead leaves, presence of waterway) may increase the risk of AM. Specific interventions based on these factors might help to reduce the incidence of AM.

  20. Carbon balance of an intensively grazed permanent grassland in southern Belgium

    NASA Astrophysics Data System (ADS)

    Gourlez de la Motte, Louis; Jérôme, Elisabeth; Mamadou, Ossénatou; Beckers, Yves; Bodson, Bernard; Heineisch, Bernard; Aubinet, Marc

    2016-04-01

    Grasslands are an important component of the global carbon balance but their carbon storage potential is still highly uncertain. Especially, the impact of weather variability and management practices on grassland carbon budgets need to be assessed. This study investigates the carbon balance of an intensively managed permanent grassland (Dorinne Terrestrial Observatory (DTO)) and its uncertainties by combining 5-years of eddy covariance measurements and other organic carbon exchanges estimates. The specificities of this study lie in: (i) the age of the pasture, which has probably been established since more than one century; (ii) the intensive character of the management with a mean grazing pressure larger than 2 livestock unit ha-1 and stocking cycle including stocking and rest periods, (iii) the livestock production system, typical of Wallonia, farming intensively Belgian Blue breed of cattle in order to produce meat. The results showed that, despite the high stocking rate and the old age of the pasture and the high stocking rate, the site acted as a relatively stable carbon sink from year to year with a 5-year average Net Biome Productivity of ‒173 [‒128 ‒203] g C m-2 yr-1. The carbon sink behavior of the pasture was directly increased by management practices through food complementation and organic fertilization and indirectly by mineral fertilization. The relatively low carbon budget inter-annual variability could be explained both by: (i) grazing management of the farmer that regulated Growth Primary Productivity by adapting the stocking rate to the Leaf Area Index which itself depends on weather conditions, (ii) carbon imports through food complements only when grass regrowth was not sufficient to feed the cattle. The results suggest that management practices that tend to optimize forage availability for meat production could contribute to maintaining a carbon sink. Keywords : grassland, carbon budget, carbon dioxide flux, management, eddy covariance

  1. Purple Prairie Clover (Dalea purpurea Vent) Reduces Fecal Shedding of Escherichia coli in Pastured Cattle.

    PubMed

    Jin, L; Wang, Y; Iwaasa, A D; Li, Y; Xu, Z; Schellenberg, M P; Liu, X L; McAllister, T A; Stanford, K

    2015-08-01

    A 3-year (2009 to 2011) grazing study was conducted to assess the effects of purple prairie clover (PPC; Dalea purpurea Vent) on fecal shedding of total Escherichia coli in cattle. Three pasture types were used in the experiment: bromegrass (Check), mixed cool season grasses with PPC (Simple), and mixed cool and warm grasses with PPC (Complex). Pastures were rotationally grazed during a summer and fall grazing period. PPC was grazed in summer at the vegetative or early flower stage and at the flower or early seed stage during the fall. Fecal samples were collected for enumeration of E. coli and chemical analyses. Forage samples were collected throughout grazing for analysis. Condensed tannins (CT) were only detected in Simple and Complex pastures that contained PPC, with higher concentrations found in the fall than in the summer. Fecal counts of E. coli in cattle grazing Simple and Complex pastures linearly decreased (P < 0.05) over summer to fall in all 3 years, an outcome not observed in cattle grazing the Check pasture. Across the three grazing seasons, fecal E. coli was lower (P < 0.05) in cattle grazing Simple and Complex pastures than in those grazing the Check pasture during the fall. During the fall, feces collected from cattle grazing the Check pasture had higher (P < 0.05) values for pH, N, NH3-N, total volatile fatty acids, and branched-chain volatile fatty acids, but a lower (P < 0.05) acetate:propionate ratio than feces collected from cattle grazing Simple or Complex pastures. In a second experiment, two strains of E. coli were cultured in M9 medium containing 25 to 200 μg/ml of PPC CT. Growth of E. coli was linearly (P < 0.01) reduced by increasing levels of PPC CT. Scanning electron micrographs showed electron-dense filamentous material associated with the outer membrane of E. coli cells exposed to CT. Incorporation of PPC into forage reduced the fecal shedding of E. coli from grazing cattle, likely due to the anti-E. coli properties of PPC CT.

  2. Pasture diversity and management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Scientists at the USDA-ARS Pasture Systems and Watershed Management Research Unit have been collecting pasture plant biodiversity data for over ten years and across the northeastern United States. We have identified more than three hundred species of vascular plants. The average pasture in this regi...

  3. [Effect of grazing on sandy grassland ecosystem in Inner Mongolia].

    PubMed

    Zhao, Halin; Zhang, Tonghui; Zhao, Xueyong; Zhou, Ruilian

    2004-03-01

    This experiment was carried out for 5 years in Horqin sandy land, lnner Mongolia, which had 4 treatments: Non-grazing (NG), light grazing (LG), moderate grazing (MG) and over grazing (OG). The results showed that different grazing intensities resulted in different development trend of the pasture ecosystem, of which, the injury of OG on pasture ecosystem was very great. The plant diversity, vegetation coverage, plant height and primary productivity under continuous overgrazing for 5 year were 87.9%, 82.1%, 94.0% and 57.0%, respectively, lower than those in NG. The biomass on the OG pasture was only 2.1% of NG, and the contents of soil clay, C and N as well as the quantities of soil microbes and small animals in OG were respectively 6.0%, 31.9%, 25.0%, 95.0% and 75.9% lower than those in NG, but the soil hardness was raised by 274.0%. Especially, the secondary productivity of the pasture became negative from the third year, and the productive foundation of the pasture ecosystem was completely destroyed. Non-grazing was beneficial to pasture, and enclosure caused an increase in vegetation coverage, plant height and primary productivity. The vegetation coverage, plant height and soil status in LG and MG were not as good as those in NG, but were stable and didn't show worsening trend. Based on the above results, it's considered that on the sandy pasture in the semi-arid area of Inner Mongolia, the rational grass utilization ratio is 45%-50%, and the suitable loading capacity is 3-4 sheep unit.hm-2. PMID:15227991

  4. Reestablishing Chicory into Multi-Species Perennial Pastures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chicory (Cichorium intybus L.) has the potential to provide abundant, high quality forage during periods of drought stress, but poor persistence limits its usefulness in permanent pasture. This experiment compared the ability of three seeding methods to reestablish chicory into a grazed multi-specie...

  5. Heifer growth performance from fall-oat pastures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fall-grown oat has shown promise as an emergency fall forage option, or to extend the grazing season in Wisconsin. Our objectives for this project were: i) to assess the pasture productivity and forage characteristics of 2 fall-grown oat cultivars (Ogle and ForagePlus; OG and FP, respectively) using...

  6. Using lake dredged material to enhance pasture establishment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The cow-calf (Bos taurus) industry in subtropical United States and other parts of the world depends almost totally on grazed pastures. Establishment of complete, uniform stand of bahiagrass in a short time period is vital economically. Domestic wastewater sludge or sewage sludge, composted urban pl...

  7. Canopy-Coverage Method Compares Pasture and Prairie

    ERIC Educational Resources Information Center

    Jantzen, Paul G.

    1973-01-01

    Describes the procedures used by a high school biology class in an ecological study related to the degeneration of grasslands. The canopy-coverage method of vegetational analysis was used to compare a low-grade, over-grazed pasture with a nearby high-quality prairie. An interpretation of the results is also presented. (JR)

  8. Pasture improvement in Spanish Dehesas

    NASA Astrophysics Data System (ADS)

    Murillo Vilanova, M.; González López, F.

    2009-04-01

    In the south-west of the Iberian Peninsula, the dehesa is a widespread agro-silvo-pastoral land use system, characterized by a grassland with a disperse cover of oak trees and shrubs, where the main production is extensive livestock combined with agriculture and forestry. Many years of inappropriate management of dehesas (deforestation, overgrazing, excessive agricultural activities, etc.) has led to the degradation of vegetation and soils in extensive areas, causing reductions in biomass and biodiversity, affecting the permanence of plants and causing important losses of palatable species. As there is growing interest in these wooded rangeland ecosystems due to their economic importance and high environmental value, the recovery of the original pasture biodiversity and the increase of productivity, together with the conservation of the environment, are the main goals in these areas of low productive potential, degraded and subject to soil erosion. Soil and climate conditions have a great influence on grassland production, with rainfall producing strong seasonal and interannual variations. These natural pastures, mainly composed of summer withering annual species, reach maximum productions in spring and register low values in autumn, slowing down in winter. During the summer dry season, the wilting pastures can offer a good forage for animals. Autochthonous annual legumes play an important role because they are well adapted to local edaphic and climatic conditions and produce hard seeds which germinate in autumn. This helps them to survive the frequent droughts and offer a high quality forage, which is a valuable complement to other pasture plants with lower protein content. Therefore, for several decades, legume seeding combined with the application of phosphate fertilizer has been the most common strategy used to improve pastures in SW Spain, where dehesas cover an area of about four million hectares. This paper examines the whole process of pasture improvement

  9. Influence of grazing management on claw disorders in Swedish freestall dairies with mandatory grazing.

    PubMed

    Bergsten, C; Carlsson, J; Jansson Mörk, M

    2015-09-01

    Our hypothesis was that grazing time, the number of days (duration) and number of hours per day, affected claw health. From Swedish freestall herds that fulfilled our criteria of claw-trimming routines, 201 herds were randomly selected for a telephone interview regarding grazing management. Herd data were retrieved from the Swedish Official Milk Recording Scheme. Claw disorders to be analyzed were recorded at maintenance claw trimming before and after the grazing period and included mild and severe dermatitis, severe heel-horn erosion, and sole ulcer (including severe sole hemorrhage). Any remark included one or more of these recorded disorders. The odds for having a recorded claw disorder at the autumn trimming in relation to grazing management, as well as to herd- and cow-related parameters, was tested using multilevel logistic regression models. The final statistical analysis included 17,600 cows in 174 herds, which were distributed from the south to the north of Sweden with decreasing length of mandatory grazing period because of climate. Grazing duration was statistically associated with the risk of sole ulcer, but it was not linear. However, grazing duration was not statistically associated with the odds for any remark, dermatitis, or heel-horn erosion. The odds for dermatitis were lower with access to pasture for 24 h compared with either day or night access. Otherwise, the number of hours that the animals had access to grazing per day was not significantly associated with any of the other analyzed claw disorders. Higher pasture stocking density (number of cow hours per day per hectare) was associated with a higher odds for dermatitis and sole ulcer. For all recorded claw disorders, the highest odds for having a disorder after the grazing period were consistently when the cow had the same claw disorder before the release to pasture. The positive effects of grazing on claw health were less than expected, and the previous known effects of breed, days in milk

  10. Influence of grazing management on claw disorders in Swedish freestall dairies with mandatory grazing.

    PubMed

    Bergsten, C; Carlsson, J; Jansson Mörk, M

    2015-09-01

    Our hypothesis was that grazing time, the number of days (duration) and number of hours per day, affected claw health. From Swedish freestall herds that fulfilled our criteria of claw-trimming routines, 201 herds were randomly selected for a telephone interview regarding grazing management. Herd data were retrieved from the Swedish Official Milk Recording Scheme. Claw disorders to be analyzed were recorded at maintenance claw trimming before and after the grazing period and included mild and severe dermatitis, severe heel-horn erosion, and sole ulcer (including severe sole hemorrhage). Any remark included one or more of these recorded disorders. The odds for having a recorded claw disorder at the autumn trimming in relation to grazing management, as well as to herd- and cow-related parameters, was tested using multilevel logistic regression models. The final statistical analysis included 17,600 cows in 174 herds, which were distributed from the south to the north of Sweden with decreasing length of mandatory grazing period because of climate. Grazing duration was statistically associated with the risk of sole ulcer, but it was not linear. However, grazing duration was not statistically associated with the odds for any remark, dermatitis, or heel-horn erosion. The odds for dermatitis were lower with access to pasture for 24 h compared with either day or night access. Otherwise, the number of hours that the animals had access to grazing per day was not significantly associated with any of the other analyzed claw disorders. Higher pasture stocking density (number of cow hours per day per hectare) was associated with a higher odds for dermatitis and sole ulcer. For all recorded claw disorders, the highest odds for having a disorder after the grazing period were consistently when the cow had the same claw disorder before the release to pasture. The positive effects of grazing on claw health were less than expected, and the previous known effects of breed, days in milk

  11. Amazing Grazing.

    ERIC Educational Resources Information Center

    Peterson, Cris

    Countless acres of grasslands stretch across the American West. Centuries ago, bison roamed the range freely and lived off the grass. By the 19th century, herds of cattle grazed the same land. Over time, much of the original grassland was either plowed and planted or trampled to dust, causing the topsoil to dry up and blow away. Today many…

  12. Limitations of Vegetation Indices For Detecting Pasture Degradation: A Case Study of Montane Pastoral Systems in Central Asia

    NASA Astrophysics Data System (ADS)

    Eddy, I. M. S.; Gergel, S. E.

    2015-12-01

    Grazing is the most extensive land use on Earth. Widespread consequences of overgrazing pastures include long-term decreases in plant biomass and limited recovery of vegetation. Remotely-sensed vegetation indices linked to biomass (e.g. NDVI) are routinely used to monitor pasture health over broad areas to track pasture degradation and recovery over time. Unfortunately, overgrazing can impact vegetation in various other ways not easily evaluated using satellite imagery, such as by altering species composition. Furthermore, the response of vegetation to grazing may be influenced by underlying terrain and topographic gradients. We examined multi-decadal trends in pasture condition in Kyrgyzstan, a country where pasture degradation is of serious concern. Using a chronosequence of Moderate-Resolution Imaging Spectroradiometer (MODIS) imagery, we compared fifteen-year trends in NDVI with contemporary field-based measurements of pasture health in thirty 1-km 2 sites. Multivariate regression was used to discern the relationship between long-term NDVI trends and pasture health in pastures of differing terrain (areas of varying topographic wetness index and solar insolation). Preliminary results suggest that pasture degradation can be correlated with either positive or negative changes in NDVI depending upon the topographic position of the pasture. Furthermore, terrain characteristics explained a considerable portion of the observed variance in NDVI trends across the region. Improving our understanding of grazing impacts in montane systems is critical given their vulnerability to impending climate change.

  13. The impact of buffer strips and stream-side grazing on small mammals in southwestern Wisconsin

    USGS Publications Warehouse

    Chapman, Erik W.; Ribic, C.A.

    2002-01-01

    The practice of continuously grazing cattle along streams has caused extensive degradation of riparian habitats. Buffer strips and managed intensive rotational grazing (MIRG) have been proposed to protect and restore stream ecosystems in Wisconsin. However, the ecological implications of a switch from traditional livestock management to MIRG or buffer strip establishment have not been investigated. Differences in small mammal communities associated with riparian areas on continuously grazed and MIRG pastures, as well as vegetative buffer strips adjacent to row crops, were investigated in southwestern Wisconsin during May-September 1997 and 1998. More species (mean of 6-7) were found on the buffer sites than on the pasture sites (mean of 2-5). Total small mammal abundance on buffer sites was greater than on the pastures as well: there were 3-5 times as many animals on the buffer sites compared to the pasture sites, depending on year. There were no differences in species richness or total abundance between MIRG and continuously grazed pastures in either year. Total small mammal abundance was greater near the stream than away from the stream, regardless of farm management practice but there were no differences in species richness. Buffer strips appear to support a particularly rich and abundant small mammal community. Although results did not detect a difference in small mammal use between pasture types, farm-wide implications of a conversion from continuous to MIRG styles of grazing may benefit small mammals indirectly by causing an increase in the prevalence of pasture in the agricultural landscape.

  14. Restoration of the fire-grazing interaction in Artemisia filifolia shrubland

    USGS Publications Warehouse

    Winter, S.L.; Fuhlendorf, S.D.; Goad, C.L.; Davis, C.A.; Hickman, K.R.; Leslie, David M.

    2012-01-01

    Patterns of landscape heterogeneity are crucial to the maintenance of biodiversity in shrublands and grasslands, yet management practices in these ecosystems typically seek to homogenize landscapes. Furthermore, there is limited understanding of how the interaction of ecological processes, such as fire and grazing, affects patterns of heterogeneity at different spatial scales. We conducted research in Artemisia filifolia (Asteraceae) shrublands located in the southern Great Plains of North America to determine the effect of restoring the fire-grazing interaction on vegetation structure. Data were collected for 3years in replicated pastures grazed by cattle Bos taurus where the fire-grazing interaction had been restored (fire and grazing=treatment pastures) and in pastures that were grazed but remained unburned (grazing only, no fire=control pastures). The effect of the fire-grazing interaction on heterogeneity (variance) of vegetation structure was assessed at scales from 12??5m 2 to 609ha. Most measurements of vegetation structure within treatment pastures differed from control pastures for 1-3years after being burned but were thereafter similar to the values found in unburned control pastures. Treatment pastures were characterized by a lower amount of total heterogeneity and a lower amount of heterogeneity through time. Heterogeneity of vegetation structure tended to decrease as the scale of measurement increased in both treatment and control pastures. There was deviation from this trend, however, in the treatment pastures that exhibited much higher heterogeneity at the patch scale (mean patch size=202ha) of measurement, the scale at which patch fires were conducted. Synthesis and applications.Vegetation structure in A. filifolia shrublands of our study was readily altered by the fire-grazing interaction but also demonstrated substantial resilience to these effects. The fire-grazing interaction also changed the total amount of heterogeneity characterizing this

  15. Feeding strategy and pasture quality relative to nutrient requirements of dairy cows in the northeastern U.S.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pasture samples (n = 380) collected during the grazing season on 14 dairy farms from 2012 to 2014 were analyzed for nutritional composition to determine the frequency of pasture samples that met minimum net energy for lactation (NEl), crude protein (CP), and macro-mineral requirements according to t...

  16. Soil aggregates and their associated carbon and nitrogen content in winter annual pastures using different tillage management options

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Traditionally, winter annual pastures are established on grazing areas that are steeply sloping and not regarded as suitable for row-crop production. Using conventional (CT) tillage methods to prepare these fragile lands for winter annual pastures leads to increased erosion and rapid soil degradatio...

  17. Vegetation selection by Angus crossbred vs. Raramuri Criollo nursing cows grazing Chihuauan Desert rangeland in summer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We examined vegetation selection patterns of nursing Angus X Hereford crossbred (AH) and Raramuri Criollo (RC) cows grazing Chihuahuan Desert vegetation during the growing season. Eleven cows of each group grazed separately in two large pastures (1190ha, 1165ha) from mid-July until mid-August 2015 (...

  18. Effects of cultivar and grazing initiation date on fall-grown oat for replacement dairy heifers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fall-grown oat has shown promise for extending the grazing season in Wisconsin, but the optimum date for initiating grazing has not been evaluated. Our objectives for this project were: i) to assess the pasture productivity and nutritive value of 2 oat cultivars (Ogle and ForagePlus; OG and FP, resp...

  19. Chaparral Herbicide Application for Suppression of Seedhead Emergence in Tall Fescue Pastures and Possible Alleviation of Fescue Toxicosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chaparral® herbicide has shown in small-plot experiments to suppress seed head emergence in tall fescue. A two-yr grazing experiment is being conducted with steers grazed on endophyte-infected tall fescue pastures that are either treated or untreated with Chaparral® herbicide. The objective of the...

  20. Land use intensity trajectories on Amazonian pastures derived from Landsat time series

    NASA Astrophysics Data System (ADS)

    Rufin, Philippe; Müller, Hannes; Pflugmacher, Dirk; Hostert, Patrick

    2015-09-01

    Monitoring changes in land use intensity of grazing systems in the Amazon is an important prerequisite to study the complex political and socio-economic forces driving Amazonian deforestation. Remote sensing offers the potential to map pasture vegetation over large areas, but mapping pasture conditions consistently through time is not a trivial task because of seasonal changes associated with phenology and data gaps from clouds and cloud shadows. In this study, we tested spectral-temporal metrics derived from intra-annual Landsat time series to distinguish between grass-dominated and woody pastures. The abundance of woody vegetation on pastures is an indicator for management intensity, since the duration and intensity of land use steer secondary succession rates, apart from climate and soil conditions. We used the developed Landsat-based metrics to analyze pasture intensity trajectories between 1985 and 2012 in Novo Progresso, Brazil, finding that woody vegetation cover generally decreased after four to ten years of grazing activity. Pastures established in the 80s and early 90s showed a higher fraction of woody vegetation during their initial land use history than pastures established in the early 2000s. Historic intensity trajectories suggested a trend towards more intensive land use in the last decade, which aligns well with regional environmental policies and market dynamics. This study demonstrates the potential of dense Landsat time series to monitor land-use intensification on Amazonian pastures.

  1. Determination of pasture quality using airborne hyperspectral imaging

    NASA Astrophysics Data System (ADS)

    Pullanagari, R. R.; Kereszturi, G.; Yule, Ian J.; Irwin, M. E.

    2015-10-01

    Pasture quality is a critical determinant which influences animal performance (live weight gain, milk and meat production) and animal health. Assessment of pasture quality is therefore required to assist farmers with grazing planning and management, benchmarking between seasons and years. Traditionally, pasture quality is determined by field sampling which is laborious, expensive and time consuming, and the information is not available in real-time. Hyperspectral remote sensing has potential to accurately quantify biochemical composition of pasture over wide areas in great spatial detail. In this study an airborne imaging spectrometer (AisaFENIX, Specim) was used with a spectral range of 380-2500 nm with 448 spectral bands. A case study of a 600 ha hill country farm in New Zealand is used to illustrate the use of the system. Radiometric and atmospheric corrections, along with automatized georectification of the imagery using Digital Elevation Model (DEM), were applied to the raw images to convert into geocoded reflectance images. Then a multivariate statistical method, partial least squares (PLS), was applied to estimate pasture quality such as crude protein (CP) and metabolisable energy (ME) from canopy reflectance. The results from this study revealed that estimates of CP and ME had a R2 of 0.77 and 0.79, and RMSECV of 2.97 and 0.81 respectively. By utilizing these regression models, spatial maps were created over the imaged area. These pasture quality maps can be used for adopting precision agriculture practices which improves farm profitability and environmental sustainability.

  2. Soil nitrogen and carbon impacts of raising chickens on pasture

    NASA Astrophysics Data System (ADS)

    Ryals, R.; Leach, A.; Tang, J.; Hastings, M. G.; Galloway, J. N.

    2014-12-01

    Chicken is the most consumed meat in the US, and production continues to intensify rapidly around the world. Chicken manure from confined feeding operations is typically applied in its raw form to nearby croplands, resulting in hotspots of soil nitrous oxide (N2O) emissions. Pasture-raised chicken is an alternative to industrial production and is growing in popularity with rising consumer demand for more humanely raised protein sources. In this agricultural model, manure is deposited directly onto grassland soils where it is thought to increase pools of soil carbon and nitrogen. The fate of manure nitrogen from pasture-raised chicken production remains poorly understood. We conducted a controlled, replicated experiment on a permaculture farm in Charlottesville, Virginia (Timbercreek Organics) in which small chicken coops (10 ft x 12 ft) were moved daily in a pasture. We measured manure deposition rates, soil inorganic nitrogen pools, soil moisture, and soil N2O and CO2 emissions. Measurements were made for the 28-day pasture life of three separate flocks of chickens in the spring, summer, and fall. Each flock consisted of approximately 200-300 chickens occupying three to five coops (~65 chickens/coop). Measurements were also made in paired ungrazed control plots. Manure deposition rates were similar across flocks and averaged 1.5 kgdrywt ha-1 during the spring grazing event and 4.0 kgdrywt ha-1 during the summer and fall grazing events. Manure deposition was relatively constant over the four weeks pasture-lifetime of the chickens. Compared to control plots, grazed areas exhibited higher soil N2O and CO2 fluxes. The magnitude of these fluxes diminished significantly over the four-week span. Soil gas fluxes significantly increased following rainfall events. For a given rainfall event, higher fluxes were observed from transects that were grazed more recently. Soil gaseous reactive nitrogen losses were less in this pasture system compared to cultivated field amended

  3. Production and economic potentials of cattle in pasture-based systems of the western Amazon region of Brazil.

    PubMed

    Rueda, B L; Blake, R W; Nicholson, C F; Fox, D G; Tedeschi, L O; Pell, A N; Fernandes, E C M; Valentim, J F; Carneiro, J C

    2003-12-01

    Our objectives were to evaluate strategies to improve productivity and economic returns from beef and dual-purpose cattle systems based on data collected on one dual-purpose (Bos taurus x Bos indicus) and two beef (Nellore) cattle farms in the western Amazon region of Brazil. Forage chemical composition and digestion rates of carbohydrate fractions of grazed Brachiaria decumbens and Brachiaria brizantha cv. Marandu grasses and Pueraria phaseoloides (tropical kudzu) legume were measured monthly during a 9-mo period from the end of one dry season to the end of the subsequent rainy season. Measurements of milk and growth responses to grazing these forages were used to predict animal productivity responses to dietary nutrient availability throughout an annual cycle. The ME available for gain in our simulations was always more limiting than metabolizable protein. The predicted ME available for gain was 0.50 kg/d for steers grazing B. brizantha and 0.40 kg/d for finishing steers grazing B. decumbens. Grasses contained more NDF and neutral detergent insoluble protein and less ME (P < 0.05) in the rainiest months than in the less rainy season, which resulted in 20% less predicted weight gain by growing steers (P < 0.05). Supplementation with sorghum grain was required to increase milk production and growth by 25 or 50% per animal, respectively, but this strategy was less profitable than current forage-only diets. Greater productivity of land and labor from higher stocking indicated greater net margins for beef production, but not for milk. This study suggested that more intensive beef production by judicious fertilization of grass-legume pastures and greater stocking density is the preferable strategy for owners of these cattle systems to improve economic returns under current conditions. It also might help decrease the motivation for additional forest clearing.

  4. Mixed Grazing Systems Benefit both Upland Biodiversity and Livestock Production

    PubMed Central

    Fraser, Mariecia D.; Moorby, Jon M.; Vale, James E.; Evans, Darren M.

    2014-01-01

    Background With world food demand expected to double by 2050, identifying farming systems that benefit both agricultural production and biodiversity is a fundamentally important challenge for the 21st century, but this has to be achieved in a sustainable way. Livestock grazing management directly influences both economic outputs and biodiversity on upland farms while contributing to potentially damaging greenhouse gas emissions, yet no study has attempted to address these impacts simultaneously. Methods Using a replicated, landscape-scale field experiment consisting of five management ‘systems’ we tested the effects of progressively altering elements within an upland farming system, viz i) incorporating cattle grazing into an upland sheep system, ii) integrating grazing of semi-natural rough grazing into a mixed grazing system based on improved pasture, iii) altering the stocking ratio within a mixed grazing system, and iv) replacing modern crossbred cattle with a traditional breed. We quantified the impacts on livestock productivity and numbers of birds and butterflies over four years. Results, Conclusion and Significance We found that management systems incorporating mixed grazing with cattle improve livestock productivity and reduce methane emissions relative to sheep only systems. Systems that also included semi-natural rough grazing consistently supported more species of birds and butterflies, and it was possible to incorporate bouts of summer grazing of these pastures by cattle to meet habitat management prescriptions without compromising cattle performance overall. We found no evidence that the system incorporating a cattle breed popular as a conservation grazer was any better for bird and butterfly species richness than those based on a mainstream breed, yet methane emissions from such a system were predicted to be higher. We have demonstrated that mixed upland grazing systems not only improve livestock production, but also benefit biodiversity

  5. Sward structure and nutritive value of Alexandergrass fertilized with nitrogen.

    PubMed

    Salvador, Paulo R; Pötter, Luciana; Rocha, Marta G; Hundertmarck, Anelise P; Sichonany, Maria José O; Amaral Neto, Luiz G; Negrini, Mateus; Moterle, Paulo H

    2016-03-01

    This experiment evaluated forage production, sward structure, stocking rate, weight gain per area and nutritive value of forage as grazed by beef heifers on Alexandergrass (Urochloa plantaginea (Link) Hitch) pasture fertilized with nitrogen (N): 0; 100; 200 or 300 kg of N/ha. The experiment was a completely randomized design following a repeated measurement arrangement. The experimental animals were Angus heifers with initial age and weight of 15 months and 241.5±5 kg, respectively. The grazing method was continuous, with put-and-take stocking. N utilization, regardless of the level, increase by 25% the daily forage accumulation rate and the weight gain per area by 23%. The level of 97.2 kg N/ha leads to a higher leaf blade mass and increases by 20% the leaf:stem ratio. Alterations in sward structure changes the nutritive value of forage as grazed. The utilization of 112.7 kg of N/ha allows the highest stocking rate (2049.8 kg of BW/ha), equivalent to 7.5 heifers per hectare.

  6. Perspectives on pasture versus indoor feeding of dairy cows.

    PubMed

    Knaus, Wilhelm

    2016-01-15

    The dairy industry in many regions of the world has moved towards a high-input/high-output system maximising annual milk production per cow, primarily through increasing concentrate-based total mixed rations fed indoors year round, as opposed to allowing cows to feed on pasture. Pasture-based dairy systems in regions like New Zealand and Ireland are oriented towards maximum milk yield per unit of pasture, which has led to Holstein strains that are 50 to 100 kg lighter, exhibit a higher body condition score, and produce roughly half the annual amount of milk as compared to their Holstein counterparts kept in confinement in North America and Europe. Freedom from hunger might not be guaranteed when high-yielding dairy cows are kept on pasture without any supplemental feed, but at the same time no access to pasture can be considered an animal welfare concern, because pasturing is generally beneficial to the animals' health. On pasture, lighter-weight dairy cows with a medium milk production potential have proven to be superior with regard to feed efficiency and fertility. The year-round indoor feeding of high-yielding dairy cows with total mixed rations containing substantial amounts of human-edible crops from arable land puts global food security at risk and fails to utilise the evolutionary advantages of ruminants.

  7. Perspectives on pasture versus indoor feeding of dairy cows.

    PubMed

    Knaus, Wilhelm

    2016-01-15

    The dairy industry in many regions of the world has moved towards a high-input/high-output system maximising annual milk production per cow, primarily through increasing concentrate-based total mixed rations fed indoors year round, as opposed to allowing cows to feed on pasture. Pasture-based dairy systems in regions like New Zealand and Ireland are oriented towards maximum milk yield per unit of pasture, which has led to Holstein strains that are 50 to 100 kg lighter, exhibit a higher body condition score, and produce roughly half the annual amount of milk as compared to their Holstein counterparts kept in confinement in North America and Europe. Freedom from hunger might not be guaranteed when high-yielding dairy cows are kept on pasture without any supplemental feed, but at the same time no access to pasture can be considered an animal welfare concern, because pasturing is generally beneficial to the animals' health. On pasture, lighter-weight dairy cows with a medium milk production potential have proven to be superior with regard to feed efficiency and fertility. The year-round indoor feeding of high-yielding dairy cows with total mixed rations containing substantial amounts of human-edible crops from arable land puts global food security at risk and fails to utilise the evolutionary advantages of ruminants. PMID:26010136

  8. Reproductive performance of ewes grazing lucerne during different periods around mating.

    PubMed

    Robertson, S M; Clayton, E H; Friend, M A

    2015-11-01

    High intake of lucerne pastures or feeding of other high quality diets during early pregnancy may increase embryo mortality, negating any benefit of improved nutrition on ovulation rate in ewes. This study was conducted to determine whether grazing ewes on lucerne (Medicago sativa) pastures for 7 days prior to and throughout joining would result in greater foetal numbers than if ewes were removed 7 days after the commencement of joining, or if ewes grazed senescent pasture throughout the joining period. Merino ewes (300) were allocated to two replicates of three treatments, grazing pastures between Days -7 and 36 of an unsynchronised, natural autumn joining. Grazing lucerne to Day 7 of joining resulted in 30% more (P<0.05) foetuses per ewe than grazing senescent pasture (1.60±0.07 and 1.31±0.07, respectively), and 19% more lambs marked per ewe joined. Extending grazing of lucerne past Day 7 of joining did not result in additional foetuses per ewe (1.61±0.06) in comparison with only grazing lucerne to Day 7 of joining. Greater than 80% of ewes mated during the first 14 days of joining, and the proportions of ewes returning to oestrus and re-mating (0.18±0.022) and of non-pregnant (0.09±0.017) ewes were similar (P>0.05) among all treatment groups, suggesting no differences between treatments in embryo mortality. Grazing naturally cycling ewes on lucerne prior to and during joinings in autumn is recommended as a means to increase the number of lambs born, although additional gains may not be obtained by grazing past day seven of joining. PMID:26454684

  9. Objective indicators of pasture degradation from spectral mixture analysis of Landsat imagery

    NASA Astrophysics Data System (ADS)

    Davidson, Eric A.; Asner, Gregory P.; Stone, Thomas A.; Neill, Christopher; Figueiredo, Ricardo O.

    2008-03-01

    Degradation of cattle pastures is a management concern that influences future land use in Amazonia. However, "degradation" is poorly defined and has different meanings for ranchers, ecologists, and policy makers. Here we analyze pasture degradation using objective scalars of photosynthetic vegetation (PV), nonphotosynthetic vegetation (NPV), and exposed soil (S) derived from Landsat imagery. A general, probabilistic spectral mixture model decomposed satellite spectral reflectance measurements into subpixel estimates of PV, NPV, and S covers at ranches in western and eastern Amazonia. Most pasture management units at all ranches fell along a single line of decreasing PV with increasing NPV and S, which could be considered a degradation continuum. The ranch with the highest stocking densities and most intensive management had greater NPV and S than a less intensively managed ranch. The number of liming, herbiciding, and disking treatments applied to each pasture management unit was positively correlated with NPV and negatively correlated with PV. Although these objective scalars revealed signs of degradation, intensive management kept exposed soil to <40% cover and maintained economically viable cattle production over several decades. In ranches with few management inputs, the high PV cover in young pastures declined with increasing pasture age, while NPV and S increased, even where grazing intensity was low. Both highly productive pastures and vigorous regrowth of native vegetation cause high PV values. Analysis of spectral properties holds promise for identifying areas where grazing intensity has exceeded management inputs, thus increasing coverage of senescent foliage and exposed soil.

  10. Bison grazing ecology at the Rocky Mountain Arsenal National Wildlife Refuge, Colorado

    USGS Publications Warehouse

    Germaine, Stephen S.; Zeigenfuss, Linda C.; Schoenecker, Kathryn A.

    2013-01-01

    The Rocky Mountain Arsenal (RMA) National Wildlife Refuge reintroduced bison to a small pasture in 2007. Refuge managers needed information on the effects of bison grazing on vegetation communities in the bison pasture as well as information on how bison might affect other management priorities at RMA. In particular, RMA managers were interested in bison grazing effects on vegetation productivity, amount of vegetation utilization by bison, and habitat selection by bison to inform RMA herd managers and for potential expansion of bison range on the refuge. In 2007, U.S. Geological Survey (USGS) designed a study to investigate bison grazing effects through measurement of vegetation in the 600-hectare enclosure where the bison are currently pastured. This research was a collaborative effort between USGS and RMA refuge staff and had active field components in 2007 and 2010. We found that the effects and intensity of bison grazing on vegetation in the RMA bison pasture is linked to prairie dog presence. Where both species were present, they were removing a significant amount of biomass compared to areas where only bison were present. Also, prairie dogs appeared to enhance the greater production of native forbs, but we were not able to identify the mechanism for this increased production. We were not able, however, to generate an accurate vegetation map for the bison pasture, and this limited our ability to achieve the level of statistical precision necessary to identify grazing impacts and habitat selection of bison.

  11. Prescribed grazing as a secondary impact in a western riparian floodplain

    USGS Publications Warehouse

    Sedgwick, J.A.; Knopf, F.L.

    1991-01-01

    The effect of late-autumn cattle grazing on plant biomass was examined in a western Great Plains cottonwood riparian zone prone to catastrophic flooding every 5-8 years. Following 1 year of pre-treatment data collection in 1982, five 16-ha pastures were grazed from 1982 to 1984 and compared to 5 control pastures within the South Platte River floodplain in northeastern Colorado. At a prescribed grazing level of 0.46 ha/AUM, riparian vegetation proved to be resilient to the impacts of grazing. We detected only a few significant treatment effects for above-ground biomass after succeeding growing seasons. Willows (Salix spp.) responded negatively to grazing whereas biomass of prairie cordgrass (Spartina pectinata Link) was greater on grazed plots. Yearly changes in above-ground biomass, especially dramatic following a severe flood in 1983, suggest that periodic, catastrophic flooding is a major perturbation to the ecosystem, and in conjunction with our results on grazing impacts, indicate that dormant-season grazing within Soil Conservation Service (SCS) guidelines is a comparatively minor impact within the floodplain. In addition, grazing impacts were probably further mitigated by a major forage supplement of cottonwood leaves which was available at the time of cattle introductions. This local forage supplement ultimately created a lighter grazing treatment than that originally prescribed.

  12. Alterations in serotonin receptor-induced contractility of bovine lateral saphenous vein in cattle grazing endophyte-infected tall fescue

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As part of a large 2-year study documenting the physiologic impact of grazing endophyte-infected tall fescue on growing cattle, 2 experiments were conducted to characterize and evaluate the effects of grazing 2 levels of toxic endophyte-infected tall fescue pastures on vascular contractility and ser...

  13. Plant interspaces resulting from contrasting grazing management in northern mixed-grass prairie:Implications for ecosystem function

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We assessed plant basal gaps in July 2007 using continuous line intercepts in twice-replicated pastures of northern mixed-grass prairie with two grazing treatments: 1) long-term (25 years) heavily grazed, dominated by the bunchgrass blue grama (Bouteloua gracilis), and 2) ungrazed, dominated by the ...

  14. The influence of grazing on surface climatological variables of tallgrass prairie

    NASA Technical Reports Server (NTRS)

    Seastedt, T. R.; Dyer, M. I.; Turner, Clarence L.

    1992-01-01

    Mass and energy exchange between most grassland canopies and the atmosphere are mediated by grazing activities. Ambient temperatures can be increased or decreased by grazers. Data have been assembled from simulated grazing experiments on Konza Prairie Research Natural Area and observations on adjacent pastures grazed by cattle show significant changes in primary production, nutrient content, and bidirectional reflectance characteristics as a function of grazing intensity. The purpose of this research was to provide algorithms that would allow incorporation of grazing effects into models of energy budgets using remote sensing procedures. The approach involved: (1) linking empirical measurements of plant biomass and grazing intensities to remotely sensed canopy reflectance, and (2) using a higher resolution, mechanistic grazing model to derive plant ecophysiological parameters that influence reflectance and other surface climatological variables.

  15. Ryegrass pasture combined with partial total mixed ration reduces enteric methane emissions and maintains the performance of dairy cows during mid to late lactation.

    PubMed

    Dall-Orsoletta, Aline C; Almeida, João Gabriel R; Carvalho, Paulo C F; Savian, Jean V; Ribeiro-Filho, Henrique M N

    2016-06-01

    The inclusion of grazed pasture in dairy feeding systems based on a total mixed ration (TMR) reduces feed costs, benefits herd health, and reduces environmental impact. The present study aimed to evaluate the effect of ryegrass pasture combined with a partial TMR on enteric methane emissions, dry matter intake (DMI), and performance of dairy cows from mid to late lactation. The experimental treatments included 100% TMR (control), partial TMR + 6h of continuous grazing (0900-1500 h), and partial TMR + 6h of grazing that was divided into 2 periods of 3h each that took place after milking (0900-1200 h; 1530-1830 h). Twelve F1 cows (Holstein × Jersey; 132±44 DIM) were divided into 6 lots and distributed in a 3×3 Latin square design with 3 periods of 21 d (15 d of adaptation and 6 d of evaluation). Ryegrass (Lolium multiflorum Lam.) pasture was used, and the TMR was composed of 80% corn silage, 18% soybean meal, and 2% mineral and vitamin mixture, based on dry matter. The same mixture was used for cows with access to pasture. The total DMI, milk production, and 4% fat-corrected milk were similar for all cows; however, the pasture DMI (7.4 vs. 6.0kg/d) and grazing period (+ 40 min/d) were higher in cows that had access to pasture for 2 periods of 3h compared with those that grazed for a continuous 6-h period. Methane emission was higher (656 vs. 547g/d) in confined cows than in those that received partial TMR + pasture. The inclusion of annual ryegrass pasture in the diet of dairy cows maintained animal performance and reduced enteric methane emissions. The percentage of grazed forage in the cows' diet increased when access to pasture was provided in 2 periods after the morning and afternoon milking. PMID:27016830

  16. The status and importance of crude protein and macro minerals in native pastures growing on Vertisols of the central highlands of Ethiopia.

    PubMed

    Gizachew, Lemma; Smit, G N

    2012-01-01

    The effects of pasture management, season and soil nutrient status on crude protein (CP) and macro mineral concentration of native pasture was studied in the Vertisol areas of the central Ethiopian highland. Soil and herbage samples from 18 continuously grazed (CG) and 12 seasonally grazed (SG) pasture sites were analyzed for N, P, Ca, Mg, K and Na. Soil and dry season CG pasture samples were collected in January and February 2001 (dry season: November-February), while wet season CG and SG pasture samples were collected during September 2001 (wet season: April-October). The Potassium concentration (2.55%) of mixed herbage samples from SG pasture exceeded the K values (1.80%) from CG pasture (P < 0.01). Significant (P < 0.01) differences of CP and macro minerals concentrations were noted among forage species. The mean CP and K concentrations of herbage from CG pasture were higher (P < 0.01) during the wet than during the dry season (5.97 and 1.80% vs. 3.18 and 0.79%), while the opposite was true for Ca (0.49% vs. 0.61%) (P < 0.05). Regarding soil macro minerals and the corresponding herbage macro mineral concentrations, significant (P < 0.05) but inconsistent correlations were found for Ca, P, Mg and Na. The results suggest that pasture management, season and to some extend soil nutrient status, can affect herbage CP and macro mineral composition. The levels of CP in CG pasture and that of P and Na in both CG and SG pastures may fall below the requirements of grazing livestock. Resting at critical stages of the growth cycle of the forage species encouraged the recovery of desirable species. For this reason resting of pasture can contribute significantly to the quality of the native pastures of the Vertisols of the central Ethiopian highlands and should be encouraged.

  17. Seasonal and diurnal variation in simple sugar and fructan composition of orchardgrass pasture and hay in the Piedmont region of the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Laminitis, a disease that causes lameness in horses, is thought to result from grazing on grass high in carbohydrates. Consequently, knowing the amounts and types of carbohydrates in a pasture may help horse owners to manage grazing in a way that reduces the risk of laminitis. This study describes...

  18. Effect of stocking rate on milk and pasture productivity and supplementary feed use for spring calving pasture fed dairy systems.

    PubMed

    Patton, D; Pierce, K M; Horan, B

    2016-07-01

    The productivity of grazing systems is primarily limited by the scale and efficiency of systems applied to the grazable land platform adjacent to the milking parlor. The objective of this study was to compare forage production, utilization and quality, milk production, and requirement for supplementary feeds for 2 different grazing platform stocking rate (GPSR) treatments over 4 yr. Animals were randomly allocated to 1 of 2 GPSR treatments: high-closed (HC; 3.1 cows/ha) and high-open (HO; 4.5 cows/ha), which were designed to represent alternative GPSR in a post-European Union milk quota, spring calving, pasture-based milk production system. Animal production data were analyzed using Proc MIXED of SAS with GPSR, year, and parity included as fixed effects in the final model. Within a seasonal spring calving grazing system, at high GPSR and offering moderate amounts of additional supplements based on pasture supply deficits, both systems produced more milk and fat plus protein per hectare in comparison with Irish commercial dairy farms. Although requiring additional supplementation, increased GPSR resulted in increased milk production per hectare but also in an increased requirement for concentrate and forage supplementation during lactation. No significant influence of GPSR was found on body weight and body condition score or reproductive performance during the 4-yr study period. In addition, GPSR also had no effect on pasture production, utilization, or quality during the study period. The strategic use of additional supplements with restricted pasture availability at higher GPSR maintained milk production per cow and significantly increased milk production per hectare. PMID:27108176

  19. Feeding strategy and pasture quality relative to nutrient requirements of organic dairy cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pasture samples (n = 216) were collected during the grazing season from 14 certified northeastern organic dairy farms in 2012 and 2013 for nutritive composition (Dairy One). A Mixed model (SAS Inst., 1998) was used to test effect of year of sampling, month of sampling, and farm on crude protein (CP...

  20. Economic and environmental issues associated with confinement and pasture-based dairy systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Milk is produced in a continuum of dairy systems from full confinement to full pasture grazing. Climate, available feeds, and milk price: feed cost ratio influence the preferred system. All dairy systems have an environmental impact and inputs to maximise profit may lead to pollution levels unacce...

  1. Nutritive Value and Herbage Accumulation Rates of Pasture Sown to Grass, Legume, and Chicory

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Planting pastures to mixtures of forages may benefit herbage production; however, wide fluctuations in botanical composition could cause unstable nutritive value. A grazing study was conducted to examine how forage mixture complexity influenced nutritive value and accumulation rate during spring, su...

  2. Pasture-derived greenhouse gas emissions in cow-calf production systems.

    PubMed

    Chiavegato, M B; Powers, W J; Carmichael, D; Rowntree, J E

    2015-03-01

    There is a lack of information regarding carbon dioxide (CO), methane (CH), and nitrous oxide (NO) emissions from pasture soils and the effects of grazing. The objective of this study was to quantify greenhouse gas (GHG) fluxes from pasture soils grazed with cow-calf pairs managed with different stocking rates and densities. The central hypothesis was that irrigated low-density stocking systems (SysB) would result in greater GHG emissions from pasture soils than nonirrigated high-density stocking systems (SysA) and grazing-exclusion (GRE) pasture sites. The nonirrigated high-density stocking systems consisted of 120 cow-calf pairs rotating on a total of 120 ha (stocking rate 1 cow/ha, stocking density 112,000 kg BW/ha, rest period of 60 to 90 d). The irrigated low-density stocking systems consisted of 64 cow-calf pairs rotating on a total of 26 ha of pasture (stocking rate 2.5 cows/ha, stocking density 32,700 kg BW/ha, rest period of 18 to 30 d). Both systems consisted of mixed cool-season grass-legume pastures. Static chambers were randomly placed for collection of CO, CH, and NO samples. Soil temperature (ST), ambient temperature (temperature inside the chamber; AT), and soil water content (WC) were monitored and considered explanatory variables for GHG emissions. GHG fluxes were monitored for 3 yr (2011 to 2013) at the beginning (P1) and at the end (P2) of the grazing season, always postgrazing. Paddock was the experimental unit (3 pseudoreplicates per treatment), and chambers (30 chambers per paddock) were considered multiple measurements of each experimental unit. A completely randomized design considered the term year × period as a repeated measure and chamber nested within paddock and treatment as the random term. Generally, SysB had greater CO emissions than SysA and GRE pasture sites across years and periods ( < 0.01). Soil temperature, AT, and WC had effects on CO emissions. Methane and NO emissions were observed from pasture sites of the 3 systems, but

  3. Community responses of arthropods to a range of traditional and manipulated grazing in shortgrass steppe.

    PubMed

    Newbold, T A Scott; Stapp, Paul; Levensailor, Katherine E; Derner, Justin D; Lauenroth, William K

    2014-06-01

    Responses of plants to grazing are better understood, and more predictable, than those of consumers in North American grasslands. In 2003, we began a large-scale, replicated experiment that examined the effects of grazing on three important arthropod groups-beetles, spiders, and grasshoppers-in shortgrass steppe of north-central Colorado. We investigated whether modifications of the intensity and seasonality of livestock grazing alter the structure and diversity of macroarthropod communities compared with traditional grazing practices. Treatments represented a gradient of grazing intensity by cattle and native herbivores: long-term grazing exclosures; moderate summer grazing (the traditional regime); intensive spring grazing; intensive summer grazing; and moderately summer-grazed pastures also inhabited by black-tailed prairie dogs (Cynomys ludovicianus Ord). Beetles and spiders were the most common groups captured, comprising 60% and 21%, respectively, of 4,378 total pitfall captures. Grasshopper counts were generally low, with 3,799 individuals observed and densities <4 m(-2). Two years after treatments were applied, vegetation structure differed among grazing treatments, responding not only to long-term grazing conditions, but also to the short-term, more-intensive grazing manipulations. In response, arthropods were, in general, relatively insensitive to these grazing-induced structural changes. However, species-level analyses of one group (Tenebrionidae) revealed both positive and negative effects of grazing treatments on beetle richness and activity-density. Importantly, these responses to grazing were more pronounced in a year when spring-summer rainfall was low, suggesting that both grazing and precipitation-which together may create the greatest heterogeneity in vegetation structure-are drivers of consumer responses in this system.

  4. Community responses of arthropods to a range of traditional and manipulated grazing in shortgrass steppe.

    PubMed

    Newbold, T A Scott; Stapp, Paul; Levensailor, Katherine E; Derner, Justin D; Lauenroth, William K

    2014-06-01

    Responses of plants to grazing are better understood, and more predictable, than those of consumers in North American grasslands. In 2003, we began a large-scale, replicated experiment that examined the effects of grazing on three important arthropod groups-beetles, spiders, and grasshoppers-in shortgrass steppe of north-central Colorado. We investigated whether modifications of the intensity and seasonality of livestock grazing alter the structure and diversity of macroarthropod communities compared with traditional grazing practices. Treatments represented a gradient of grazing intensity by cattle and native herbivores: long-term grazing exclosures; moderate summer grazing (the traditional regime); intensive spring grazing; intensive summer grazing; and moderately summer-grazed pastures also inhabited by black-tailed prairie dogs (Cynomys ludovicianus Ord). Beetles and spiders were the most common groups captured, comprising 60% and 21%, respectively, of 4,378 total pitfall captures. Grasshopper counts were generally low, with 3,799 individuals observed and densities <4 m(-2). Two years after treatments were applied, vegetation structure differed among grazing treatments, responding not only to long-term grazing conditions, but also to the short-term, more-intensive grazing manipulations. In response, arthropods were, in general, relatively insensitive to these grazing-induced structural changes. However, species-level analyses of one group (Tenebrionidae) revealed both positive and negative effects of grazing treatments on beetle richness and activity-density. Importantly, these responses to grazing were more pronounced in a year when spring-summer rainfall was low, suggesting that both grazing and precipitation-which together may create the greatest heterogeneity in vegetation structure-are drivers of consumer responses in this system. PMID:24780073

  5. Influence of grazing management on the seasonal change in testicular morphology in Corriedale rams.

    PubMed

    Bielli, A; Pedrana, G; Gastel, M T; Castrillejo, A; Moraña, A; Lundeheim, N; Forsberg, M; Rodriguez-Martinez, H

    1999-06-28

    The present study was conducted: (a) to determine the degree of seasonal variation in testis stereology in Corriedale rams between autumn and winter; (b) to test the hypothesis that testis stereology of Corriedale rams grazing native pastures during autumn and winter would differ from those of Corriedale rams grazing sown pastures and supplemented with grain during the same period; and (c) to determine whether Sertoli cell numbers differ in adult rams between the breeding season (autumn) and the following non-breeding season (winter). Twenty experimental animals were studied. Six rams (autumn control group, C-A) that had been grazing on native pasture (stocking rate = 2-3 animals ha(-1)) were castrated at the beginning of the experiment (March, early autumn). Seven rams (winter control group, C-W) continued to graze on native pasture at the same stocking rate until the end of the experiment (August, late winter). Another seven rams (treated group, T) grazed on improved pasture (stocking rate = 1-2 animals ha(-1)) and were supplemented with 1 kg grain ram(-1) day(-1) until the end of the experiment. Live weight, scrotal circumference, serum testosterone concentration and selected testicular stereological parameters were measured. The treatment did not impede the winter reduction in testicular activity and reduced its magnitude slightly (group T) compared with controls (group C-W). Sertoli cell numbers were higher in autumn (group C-A) than in winter, both on native (group C-W) and sown pastures (group T). Diminishing Sertoli cell numbers between autumn and the following winter suggest the occurrence of that Sertoli cell death during this period. The results indicate that, although the reproductive activity of Corriedale rams is moderately seasonal, a restricted change in grazing and grain supplementation can only modify it to a limited extent. PMID:10463397

  6. Cool-season annual pastures with clovers to supplement wintering beef cows nursing calves.

    PubMed

    Gunter, Stacey A; Whitworth, Whitney A; Montgomery, T Gregory; Beck, Paul A

    2012-07-24

    In December of 3 years, 87 beef cows with nursing calves (594 ± 9.8 kg; calving season, September to November) at side were stratified by body condition score, body weight, cow age, and calf gender and divided randomly into 6 groups assigned to 1 of 6 cool-season annual pastures (0.45 ha/cow) that had been interseeded into a dormant common bermudagrass (Cynodon dactylon [L.] Pers.)/bahiagrass (Paspalum notatum Flugge) sod. Pastures contained 1 of the following 3 seeding mixtures (2 pastures/mixture): 1) wheat (Triticum aestivum L.) and ryegrass (Lolium multiflorum Lam., WRG), 2) wheat and ryegrass plus red clover (Trifolium pretense L., WRR), or 3) wheat and ryegrass plus white (Trifolium repens L.) and crimson clovers (Trifolium incarnatum L., WRW). All groups had ad libitum access to grass hay (12% crude protein; 58% total digestible nutrients). The second week in December, cow estrous cycles were synchronized and artificially inseminated. In late December, a bull was placed with each group for 60-d. Data were analyzed with an analysis of variance using a mixed model containing treatment as the fixed effect and year as the random effect. Body weight and condition scores did not differ (P ≥ 0.27) among cows between February and June. Calf birth weights or average daily gain did not differ (P ≥ 0.17) among treatments; however, calves grazing pastures with clovers did tend (P = 0.06) to weigh more than calves grazing grass only. Weaning weight per cow exposed to a bull was greater (P = 0.02) for WRR and WRW than WRG. Cows grazing winter-annual pastures containing clovers tended to wean more calf body weight per cow exposed to a bull than cows grazing the grass only pastures.

  7. Cool-season annual pastures with clovers to supplement wintering beef cows nursing calves

    PubMed Central

    2012-01-01

    In December of 3 years, 87 beef cows with nursing calves (594 ± 9.8 kg; calving season, September to November) at side were stratified by body condition score, body weight, cow age, and calf gender and divided randomly into 6 groups assigned to 1 of 6 cool-season annual pastures (0.45 ha/cow) that had been interseeded into a dormant common bermudagrass (Cynodon dactylon [L.] Pers.)/bahiagrass (Paspalum notatum Flugge) sod. Pastures contained 1 of the following 3 seeding mixtures (2 pastures/mixture): 1) wheat (Triticum aestivum L.) and ryegrass (Lolium multiflorum Lam., WRG), 2) wheat and ryegrass plus red clover (Trifolium pretense L., WRR), or 3) wheat and ryegrass plus white (Trifolium repens L.) and crimson clovers (Trifolium incarnatum L., WRW). All groups had ad libitum access to grass hay (12% crude protein; 58% total digestible nutrients). The second week in December, cow estrous cycles were synchronized and artificially inseminated. In late December, a bull was placed with each group for 60-d. Data were analyzed with an analysis of variance using a mixed model containing treatment as the fixed effect and year as the random effect. Body weight and condition scores did not differ (P ≥ 0.27) among cows between February and June. Calf birth weights or average daily gain did not differ (P ≥ 0.17) among treatments; however, calves grazing pastures with clovers did tend (P = 0.06) to weigh more than calves grazing grass only. Weaning weight per cow exposed to a bull was greater (P = 0.02) for WRR and WRW than WRG. Cows grazing winter-annual pastures containing clovers tended to wean more calf body weight per cow exposed to a bull than cows grazing the grass only pastures. PMID:22958279

  8. Positive effects of millennial grazing on soils in the western French Pyrenees

    NASA Astrophysics Data System (ADS)

    Leigh, David; Gragson, Ted; Coughlan, Michael

    2015-04-01

    Many hillslopes of the western French Pyrenees have been grazed for thousands of years following the introduction of sheep about 7500 years ago, yet little is known about the long-term effects of pastoral activities on soil properties and pedogenic processes in this humid-temperate mountain range. In the 13 square kilometer Basque commune of Larrau we compare the status of soils under old pastures to those under old-growth forests at elevations ranging from 1000 to 1600 masl. Four separate tracts of side-by-side pairs of pasture and old-growth forest were sampled to discriminate differences in physical and chemical soil properties. Five paired soil profile samples were taken from each vegetation type on each tract so that all factors of soil formation, except vegetation type, were similar for each pair. Animal trails were excluded from sampling. We also developed radiocarbon chronologies of sedimentation rates from colluvial deposits at four other pasture sites to evaluate possible differences in the magnitude of soil erosion and sedimentation before and after conversion to pastures during the Holocene. Results indicate pastured A horizons are about three times as thick as forested soils, have significantly lower soil bulk densities, and much finer and stronger structural development of soil aggregates. These traits favor much greater infiltration and water holding capacities of the pastured soils. Thus, very significant pedogenic reorganization occurred in the pastures that can be viewed as improvements in soil quality. Inorganic nutrients in the pastured soils have significantly lower concentrations than in forested soils, except that amorphous silica is more abundant within pastured soils presumably due to greater phytolith production. The amount of nutrient depletion does not appear to be a limiting factor for grass growth and biomass production. Sedimentation chronologies indicate that erosion and sedimentation rates slightly increased following the earliest

  9. Potential Pasture Nitrogen Concentrations and Uptake from Autumn or Spring Applied Cow Urine and DCD under Field Conditions

    PubMed Central

    Moir, Jim; Cameron, Keith; Di, Hong

    2016-01-01

    Nitrogen (N) cycling and losses in grazed grassland are strongly driven by urine N deposition by grazing ruminants. The objective of this study was to quantify pasture N concentrations, yield and N uptake following autumn and spring deposition of cow urine and the effects of fine particle suspension (FPS) dicyandiamide (DCD). A field plot study was conducted on the Lincoln University dairy farm, Canterbury, New Zealand from May 2003 to May 2005. FPS DCD was applied to grazed pasture plots at 10 kg·ha−1 in autumn and spring in addition to applied cow urine at a N loading rate of 1000 kg·N·ha−1, with non-urine control plots. Pasture N ranged between 1.9 and 4.8% with higher concentrations from urine. Results indicated that urine consistently increased N concentrations for around 220 days post deposition (mid December/early summer) at which point concentrations dropped to background levels. In urine patches, pasture yield and annual N uptake were dramatically increased on average by 51% for autumn and 28% for spring applied urine, in both years, when DCD was applied. This field experiment provides strong evidence that annual pasture N uptake is more strongly influenced by high urine N deposition than pasture N concentrations. FPS DCD has the potential to result in very high N uptake in urine patches, even when they are autumn deposited. PMID:27304974

  10. Effects on ground-water quality from irrigating pasture with sewage effluent near Lakeland, Florida

    USGS Publications Warehouse

    Reichenbaugh, R.C.

    1977-01-01

    Since 1969 an average of 25,000 gpd of domestic secondary-treated effluent has been used to supplement irrigation of 30 acres of grazed pasture north of Lakeland, Florida. Monitor wells were contructed near the effluent-irrigated pasture. The water table in the surficial aquifer under the pasture varied from 1.0 to 3.3 feet below land surface. Total nitrogen was less than 20 percent of the effluent content after percolating 8 feet; no increase in nitrogen was detected 20 feet below the surface, or in down-gradient ground water. There was no evidence of phosphorus or carbon contamination of ground water. Low numbers of bacteria (generally coliform) were noted in some samples from nine wells. Four wells sampled contained bacteria of probable fecal origin. Low-rate application of the effluent to the pasture apparently has had little effect on the soil and ground water. (Woodard-USGS)

  11. Carbon fluxes of Kobresia pygmaea pastures on the Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Babel, Wolfgang; Biermann, Tobias; Falge, Eva; Ingrisch, Johannes; Leonbacher, Jürgen; Schleuss, Per; Kuzyakov, Yakov; Ma, Yaoming; Miehe, Georg; Foken, Thomas

    2014-05-01

    With an approximate cover of 450,000 km² on the Tibetan Plateau (TP), the Cyperaceae Kobresia pygmaea forms he world's largest alpine ecosystem. This species, especially adapted to grazing pressure, grows to a height of only 2-6 cm and can be found in an altitudinal range of 4000 to 5960 m a.s.l. A special characteristic of this ecosystem is the stable turf layer, which is built up from roots and plays a significant role in protecting soil from erosion. This is of great importance since soils on the TP store 2.5 % of the global soil organic carbon stocks. The aim of the investigation was the study of the carbon storage and the impact of human-induced land use change on these Kobresia pygmaea pastures. We therefore applied eddy-covariance measurements and modelling as a long-term control of the fluxes between the atmosphere and the pastures and 13C labelling for the investigation of flux partitioning, and chamber measurements to investigate the degradation of the pastures. Combining CO2 budgets observed in 2010 with eddy-covariance measurements and relative partitioning of carbon fluxes estimated with 13C labelling enabled us to characterise the C turnover for the vegetation period with absolute fluxes within the plant-soil-atmosphere continuum. These results revealed that this ecosystem indeed stores a great amount of C in below-ground pools, especially in the root turf layer. To further investigate the importance of the root layer, the experiments in 2012 focused on flux measurements over the different surface types which make up the heterogeneity of the Kobresia pygmaea pastures and might result from degradation due to extensive grazing. The three surface types investigated with a LiCOR long-term monitoring chamber system include Kobresia pygmaea with intact turf layer (IRM), a surface type where the turf layer is still present but the vegetation is sparse and mainly consists of Cryptogam crusts (DRM) and finally areas without the turf layer (BS). According to

  12. Rewetting effects on soil CO2 flux and nutrients leaching in alpine Kobresia pasture on the Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Liu, Shibin; Schleuss, Per; Kuzyakov, Yakov

    2015-04-01

    Kobresia pygmaea pastures of the Tibetan Plateau are one of the most important ecosystems around the world due to its large grazing area and very high soil organic carbon storage. Since the last decades grasslands of the TP are highly affected by grassland degradation because of various sedimentary programs and strongly increase grazing pressure. Climate changes (e.g. increased precipitation and temperature) may accelerate this degradation processes by enhancing soil organic matter mineralization and nutrients leaching. We exposed repeated rewetting cycles to test the effects of increased precipitation frequency on CO2 fluxes and leaching on varying K. pygmaea root mats (including: intact root mats (KL); recently died root mats (KD); crust covered root mats (LI)). Two phases were conducted (a) to identify the response of nighttime CO2 flux to changing soil moisture and (b) to investigate the impacts of rewetting cycles on day-, night-, and full day CO2 fluxes together with leaching of carbon (C) and nitrogen (N). Nighttime CO2 fluxes correlated positively with soil moisture, indicating that increasing precipitation will accelerate SOC losses due to increasing mineralization rates. KD showed highest C losses as CO2 efflux and also the highest leaching compared to KL and LI. It indicates that dying of Kobresia root mats (as induced by overgrazing and continuously removal of photosynthetically active shoot biomass) will rapidly decrease SOC storage. The lowest C losses (from soil respiration and DOC leaching) were obtained in the crust covered root mats (LI), because most C losses have already occurred during the early period. Highest N losses (especially NO3-) were obtained in the highly degraded pasture (LI). Due to long-term SOM decomposition of crust covered root mats (LI) in situ, inorganic nitrogen (NO3-) was accumulated in and was leached out during the first rewetting cycles. In contrast, no losses of NH4+ and NO3- occurred for intact Kobresia root mats (KL

  13. Influence of grazing practices on cow milk quality: a case study on the Comarnic-Poieni bauxite quarry, Romania.

    PubMed

    Lorinţ, Csaba; Rădulescu, Monica; Buia, Grigore

    2012-04-01

    The current study represents a preliminary investigation made into the influence of cattle grazing in the area of a bauxite quarry (Comarnic-Poieni, Romania) on the cow milk chemistry. Weathering and surface runoff in the bauxite quarry contaminate the local chemistry of the soil, vegetation and water. During cattle transhumance, cyclic feeding patterns occur, with grazing alternating between clean pastures and the area of the quarry. Soil and water samples were collected from the contaminated area of the quarry. Raw milk samples were collected during two stages, corresponding to the periods of grazing on clean pasture and the quarry area, respectively. Based on the obtained data, the relationship between cattle grazing and the composition of milk was interpreted. Preliminary results indicated a direct correlation of increased concentration of Al in the milk, following grazing in the bauxite quarry.

  14. Effects of pasture management and off-stream water on temporal/spatial distribution of cattle and stream bank characteristics in cool-season grass pastures.

    PubMed

    Schwarte, K A; Russell, J R; Morrical, D G

    2011-10-01

    A 2-yr grazing experiment was conducted to assess the effects of grazing management on cattle distribution and pasture and stream bank characteristics. Six 12.1-ha cool-season grass pastures in central Iowa were allotted to 1 of 3 treatments: continuous stocking with unrestricted stream access (CSU), continuous stocking with stream access restricted to 4.9-m-wide stabilized crossings (CSR), or rotational stocking with stream access restricted to a riparian paddock (RP). Pastures were stocked with 15 fall-calving Angus cows (Bos taurus L.) from mid-May to mid-October for 153 d in 2008 and 2009. A global positioning system (GPS) collar recording cow position every 10 min was placed on at least 1 cow per pasture for 2 wk of each month from May through September. Off-stream water was provided to cattle in CSU and CSR treatments during the second of the 2 wk when GPS collars were on the cattle. A black globe temperature relative humidity index (BGTHI) was measured at 10-min intervals to match the time of the GPS measurements. Each month of the grazing season, forage characteristics (sward height, forage mass, and CP, IVDMD, and P concentrations) and bare and fecal-covered ground were measured. Stream bank erosion susceptibility was visually scored in May, August, and October (pre-, mid-, and post-stocking). Cattle in RP and CSR treatments spent less time (P < 0.10) within the stream zone (0 to 3 m from stream center) in June and August and in the streamside zone (0 to 33 m from stream zone) in May through August and May through September, respectively, than cattle in CSU pastures. However, off-stream water had no effect on cattle distribution. Compared with the CSU treatment, the CSR treatment reduced the probability (P < 0.10) that cattle were within the riparian zone (0 to 36 m from stream center) at BGTHI of 50 to 100. Bare ground was greater (P < 0.10) in pastures with the CSU than CSR and RP treatments in the stream and streamside zones in September and October and

  15. Evaluation of Brassicas in grazing systems for sheep: II. Blood composition and nutrient status.

    PubMed

    Cox-Ganser, J M; Jung, G A; Pushkin, R T; Reid, R L

    1994-07-01

    Blood composition of lambs grazing Brassicas and stockpiled grass or grass-clover pastures in the fall of 4 yr was monitored to assess possible effects of plant metabolites (e.g., glucosinolates, S-methyl cysteine sulfoxide) on health and performance. Serum thyroxine (T4) concentrations in lambs grazing Brassicas decreased upon initiation of grazing, with a subsequent recovery, and concentrations were increased by oral dosing with I or I+CuO. Serum triiodothyronine (T3) increased gradually with time and did not differ between lambs on Brassicas and on pasture at most time periods. In Exp. 3 and 4, T4 levels were lower in lambs grazing Tyfon chinese cabbage hybrid (Brassica rapa L. x B. pekinensis [Lour.] Rupr.) than in lambs on Forage Star hybrid turnip (B. rapa L.). Heinz body formation increased rapidly in lambs on Brassicas, with small decreases in packed cell volume (PCV); dosing with I+CuO reduced Heinz bodies in lambs on Tyfon and turnip pastures. In Exp. 2, I+CuO treatment increased liver Cu concentrations but had no effect on serum Cu. Serum cholesterol and urea N concentrations declined rapidly in lambs on Brassicas, with little change in lambs on stockpiled pastures. Decreases in serum triglycerides, and an increase in glucose concentration, were noted in Exp. 3 and 4 in lambs grazing Tyfon and Forage Star turnip. Although a number of differences related to plant composition were noted in blood of lambs grazing Brassica forages relative to stockpiled pastures, the changes did not seem sufficiently severe to affect animal performance.

  16. Trace Element Supplementation of Livestock in New Zealand: Meeting the Challenges of Free-Range Grazing Systems

    PubMed Central

    Grace, Neville D.; Knowles, Scott O.

    2012-01-01

    Managing the mineral nutrition of free-range grazing livestock can be challenging. On farms where grazing animals are infrequently yarded, there are limited opportunities to administer trace element supplements via feeds and concentrates. In New Zealand, where the majority of sheep, cattle, and deer graze pasture year round, inadequate intake of cobalt, copper, iodine and selenium is prevalent. Scientists and farmers have developed efficient strategies to monitor and treat these dietary deficiencies. Supplementation methods suited to grazing livestock include long-acting injections, slow-release intraruminal boluses, trace element-amended fertilisers, and reticulated water supplies on dairy farms. PMID:23316417

  17. Effect of time at pasture combined with restricted indoor feeding on production and behaviour in dairy cows.

    PubMed

    Kristensen, T; Oudshoorn, F; Munksgaard, L; Søegaard, K

    2007-03-01

    Extremely high nutrient loads have been reported in grazed grassland regimes compared with cutting regimes in some dairy systems that include the use of supplemental feeding. The aim of this study was, therefore, to investigate the effects on productivity and behaviour of high-yielding dairy cows with limited access to indoor feed and restriction in the time at pasture in a continuous stocking system. During a 6-week period from the start of the grazing season 2005, an experiment was conducted with the aim of investigating the effect of restrictive indoor feeding combined with limiting the time at pasture on the productivity and behaviour of high-yielding dairy cows (31.0 ± 5.4 kg energy-corrected milk) in a system based on continuous stocking. The herd was split into three groups allocated to three treatments consisting of 4, 6.5 and 9 h at pasture, respectively. Each group of cows grazed in separate paddocks with three replicates and was separately housed in a cubicle system with slatted floor during the rest of the day. All cows were fed the same amount of supplement, adjusted daily to meet the ad libitum indoor intake of the cows at pasture for nine hours. The herbage allowance was 1650 kg dry matter (DM) per ha, and the intake of supplemental feed was 9.1 kg DM per cow daily. The limitation of the time at pasture to 4 h in combination with restrictive indoor feeding reduced the daily milk, fat and protein yield and live weight compared with 9 h of access to pasture. The proportion of time during which the cows were grazing while at pasture increased from 0.64 to 0.86 and the estimated herbage intake per h at pasture decreased from 2547 g DM to1398 g DM, when time at pasture changed from 4 to 9 h. It can be concluded, that in systems with a high herbage allowance, the cow was able to compensate for 0.8 of the reduction in time at pasture by increasing the proportion of time spent grazing and presumably also both the bite rate and mass, although the

  18. Simulated grazing responses on the proposed prairies National Park

    NASA Astrophysics Data System (ADS)

    Parton, William J.; Wright, R. Gerald; Risser, Paul G.

    1980-03-01

    The tallgrass prairie version of the ELM Grassland Model was used to evaluate the potential impact of establishing a tallgrass prairie National Park in the Flint Hills region of Kansas. This total ecosystem model simulates ( a) the flow of water, heat, nitrogen, and phosphorus through the ecosystem and( b) the biomass dynamics of plants and consumers. It was specifically developed to study the effects of levels and types of herbivory, climatic variation, and fertilization upon grassland ecosystems. The model was used to simulate the impact of building up herds of bison, elk, antelope, and wolves on a tallgrass prairie. The results show that the grazing levels in the park should not be decreased below the prepark grazing levels (moderate grazing with cattle) and that the final grazing levels in the park could be maintained at a slightly higher level than the prepark grazing levels.

  19. Estimating nitrogen excretion and deposition in grazing dairy systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current approaches to improve nutrient management on Australian dairy farms target the application of fertilizer nutrients to pastures. However, increasing animal densities and greater reliance on purchased feeds means that nutrient inputs in the form of feeds and therefore manure have increased. A ...

  20. MONITORING GRAZING LANDS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An important step in developing a ranch or allotment management plan for grazing lands is defining a rangeland monitoring program to evaluate progress toward achieving management objectives. A monitoring program can: 1) help determine the benefits gained from changes in grazing management or invest...

  1. Changes in vegetation and grazing capacity following honey mesquite control

    USGS Publications Warehouse

    McDaniel, Kirk C.; Brock, John H.; Haas, Robert H.

    1982-01-01

    Honey mesquite kill and suppression, vegetation response, and changes in grazing use and capacity were evaluated following brush control in north-central Texas. Tree grubbing was most effective for eliminating honey mesquite, but because of soil and plant damage the treatment did not increase grazing capacity or improve range condition compared to nontreated rangeland. Aerial application of 2,4,5-T + picloram was more effective in klllmg and defoliating honey mesquite than 2,4,5-T alone, but both treatments significantly increased forage production. The 2,4,5-T + picloram and 2,4,5-T sprays provided a 7 to 16% increase in grazing capacity over a 4-year period on light and heavy honey mesquite infested pastures, respectively.

  2. Grazing effects on species composition in different vegetation types (La Palma, Canary Islands)

    NASA Astrophysics Data System (ADS)

    Arévalo, J. R.; de Nascimento, L.; Fernández-Lugo, S.; Mata, J.; Bermejo, L.

    2011-05-01

    Grazing management is probably one of the most extensive land uses, but its effects on plant communities have in many cases been revealed to be contradictory. Some authors have related these contradictions to the stochastic character of grazing systems. Because of that, it is necessary to implement specific analyses of grazing effects on each community, especially in natural protected areas, in order to provide the best information to managers. We studied the effects of grazing on the species composition of the main vegetation types where it takes place (grasslands, shrublands and pine forests) on the island of La Palma, Canary Islands. We used the point-quadrat intersect method to study the species composition of grazed and ungrazed areas, which also were characterized by their altitude, distance to farms, distance to settlements, year of sampling, herbaceous aboveground biomass and soil organic matter. The variables organic matter, productivity and species richness were not significantly affected by grazing. The species composition of the analyzed plant communities was affected more by variables such as altitude or distance to farms than by extensive grazing that has been traditionally carried out on the island of La Palma involving certain practices such as continuous monitoring of animals by goat keepers, medium stocking rates adjusted to the availability of natural pastures, supplementation during the dry season using local forage shrubs or mown pastures and rotating animals within grazing areas Although some studies have shown a negative effect of grazing on endangered plant species, these results cannot be freely extrapolated to the traditional grazing systems that exert a low pressure on plant communities (as has been found in this study). We consider extensive grazing as a viable way of ensuring sustainable management of the studied ecosystems.

  3. Whole-farm phosphorus loss from grazing-based dairy farms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) loss from agricultural farms persists as a water quality impairment issue. For dairy farms, P can be lost from cropland, pastures, and open-air lots. We used interview surveys to document land use, cattle herd characteristics, and manure management for four grazing-based dairy farms i...

  4. Using the Q10 model to simulate E. coli survival in cowpats on grazing lands

    EPA Science Inventory

    Microbiological quality of surface waters can be affected by microbial load in runoff from grazing lands. This effect, with other factors, depends on the survival of microorganisms in animal waste deposited on pastures. Since temperature is a leading environmental parameter affec...

  5. Development of a lifetime merit-based selection index for US dairy grazing systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pasture-based dairy producers in the US face costs, revenues and management challenges that differ from those associated with conventional dairy production systems. Three Grazing Merit indexes (GM$1, GM$2, and GM$3), parallel to the US Lifetime Net Merit (NM$) index, were constructed using economic ...

  6. Spatial behavior and distribution of cattle grazing riparian zones in northeastern Oregon

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this research is to document and quantify the spatial movement of cattle grazing riparian pastures so that accurate assessment of use and ecological interaction can be made. Track logs with 1 second data collection intervals indicate that cows spent about 63% of their time stationar...

  7. MODELING THE POTENTIAL SPATIAL DISTRIBUTION OF BEEF CATTLE GRAZING USING A GEOGRAPHIC INFORMATION SYSTEM

    EPA Science Inventory

    Data regarding grazing utilization in the western United States are typically compiled within administrative boundaries(e.g. allotment,pasture). For large areas, an assumption of uniform distribution is seldom valid. Previous studies show that vegetation type, degree of slope, an...

  8. From the Lab Bench: The crazy notion of supplemental feeding of cattle grazing lush green forage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A column was written to discuss the reasons you may want to supplemental feed cattle grazing green and lush pastures. We know there are those times of the year when forage is actively growing, but can this forage be counted on to meet your goals in cattle production? We assume the green forage can...

  9. The effect of extended grazing time and supplementary forage on the dry matter intake and foraging behaviour of cattle kept under traditional african grazing systems.

    PubMed

    Smith, D G; Cuddeford, D; Pearson, R A

    2006-01-01

    An experiment was carried out at Alemaya University in Ethiopia to investigate the effect of night kraaling on the dry matter intake (DMI), live weight gain (LWG) and foraging behaviour of Ogaden cattle. Three groups of four animals were given either 7 h access to pasture per day, simulating traditional grazing (TG) practice; extended grazing (EG) access for 11 h per day; or traditional grazing access plus a nocturnal forage supplement (TF). Live weight gain, DMI and foraging behaviour were measured during the late dry season (EP1) and the wet season (EP2). None of the treatments had any significant effect on either DMI or LWG during EP1 or EP2. Extending pasture access time from 7 h to 11 h did not significantly increase the amount time spent grazing, but grazing intensity was significantly (p < 0.05) reduced during the non-common grazing hours. Step rate was significantly lower (p < 0.01) during EP2 than during EP1 and bites per step were significantly higher (p < 0.001) during EP2 than EP1, indicating that animals had to travel a shorter distance before selecting material to eat during the wet season (EP2). Providing supplementary forage (TF) had no significant effect on any measured parameter. In this study neither of the two low-cost methods (EG and TF) of improving access to forage had any beneficial effect on cattle productivity. It is concluded that, under the prevailing conditions, the traditional grazing practices of this part of Ethiopia do provide sufficient pasture access time to achieve daily voluntary food intake.

  10. Pasture management effects on diet composition and cattle performance on continuously stocked rhizoma peanut-mixed grass swards.

    PubMed

    Valencia, E; Williams, M J; Chase, C C; Sollenberger, L E; Hammond, A C; Kalmbacher, R S; Kunkle, W E

    2001-09-01

    In Florida, rhizoma peanut (RP; Arachis glabrata Benth.), a tropical legume, combines the attributes of excellent nutritive value, competitive ability with tropical grasses, and high animal performance. The objective of this study was to determine the effects of spring N fertilization (0 vs 35 kg/ha) and summer stocking rate (1.5 and 2.5 bulls/ha) on herbage mass, nutritive value, herbage allowance, and diet botanical composition of grazed RP-grass swards and their interaction with growth and development of bulls (Senepol, and Brahman or Angus). The study was conducted in 1995 and 1996 at the USDA, ARS, Subtropical Agriculture Research Station in Brooksville, FL. Nitrogen was applied in April of each year, and all pastures were stocked with 1.5 bulls/ha until approximately July of each year, when stocking rate was increased on half the pastures to 2.5 bulls/ha. Herbage mass (HM, kg/ha), herbage allowance (HA, kg/kg BW), nutritive value (CP and in vitro organic matter digestibility [IVOMD]), and diet botanical composition (fecal microhistological) readings were determined. Animal measurements included total and seasonal (spring vs summer), ADG, hip height (cm), scrotal circumference (SC, cm), and plasma urea nitrogen (PUN, mg/dL). Herbage mass (3.0 +/- 0.12 Mg/ha and 3.4 +/- 0.13 Mg/ha in 1995 and 1996, respectively) was not affected by nitrogen fertilization or stocking rate but was affected by season (P < 0.05) due to increased plant growth rate associated with summer rainfall. Stocking rate did affect herbage availability, but it never fell below 3 kg/kg BW, indicating herbage availability was never limiting. Crude protein (200 to 140 g/kg) and IVOMD (650 to 540 g/kg) were not affected by treatment, but declined (P < 0.001) from spring until fall. Treatments also had no effect on diet botanical composition. Summer ADG averaged about 0.2 kg/d lower than spring ADG, due, in part, to seasonal declines in nutritive value. Because herbage allowance was never limiting

  11. Grazing season and forage type influence goat milk composition and rennet coagulation properties.

    PubMed

    Inglingstad, R A; Steinshamn, H; Dagnachew, B S; Valenti, B; Criscione, A; Rukke, E O; Devold, T G; Skeie, S B; Vegarud, G E

    2014-01-01

    Two different types of pasture (cultivated and rangeland) and 2 different hay qualities (high and low quality) were examined for their effects on goat milk composition and rennet coagulation properties. Furthermore, the effect of dietary treatments in both the early and late grazing season was studied. As lactation stage is known to influence milk composition, the goats in the early and late grazing season were in the same lactation stage at the start of the experiment. The milk composition was influenced both by dietary treatment and season. Milk from goats on pasture was superior to those on hay by containing a higher content of protein and casein, and the goats on cultivated pasture had the highest milk yield. Casein composition was significantly influenced by forage treatment. Goats grazing on cultivated pasture had higher contents of αs1-casein and also of κ-casein compared with the other treatments, whereas goats grazing on rangeland had the highest content of β-casein. Factors such as milk yield, casein micelle size, αs2-casein, and calcium content were reduced in late compared with early season. More favorable rennet coagulation properties were achieved in milk from the early grazing season, with shorter firming time and higher curd firmness compared with milk from the late grazing season, but the firming time and curd firmness were not prominently influenced by forage treatment. The content of αs2-casein and calcium in the milk affected the firming time and the curd firmness positively. The influence of season and forage treatment on especially milk yield, casein content, and rennet coagulation properties is of economic importance for both the dairy industry and goat milk farmers. PMID:24704223

  12. Improved grazing management may increase soil carbon sequestration in temperate steppe.

    PubMed

    Chen, Wenqing; Huang, Ding; Liu, Nan; Zhang, Yingjun; Badgery, Warwick B; Wang, Xiaoya; Shen, Yue

    2015-07-03

    Different grazing strategies impact grassland plant production and may also regulate the soil carbon formation. For a site in semiarid temperate steppe, we studied the effect of combinations of rest, high and moderate grazing pressure over three stages of the growing season, on the process involved in soil carbon sequestration. Results show that constant moderate grazing (MMM) exhibited the highest root production and turnover accumulating the most soil carbon. While deferred grazing (RHM and RMH) sequestered less soil carbon compared to MMM, they showed higher standing root mass, maintained a more desirable pasture composition, and had better ability to retain soil N. Constant high grazing pressure (HHH) caused diminished above- and belowground plant production, more soil N losses and an unfavorable microbial environment and had reduced carbon input. Reducing grazing pressure in the last grazing stage (HHM) still had a negative impact on soil carbon. Regression analyses show that adjusting stocking rate to ~5SE/ha with ~40% vegetation utilization rate can get the most carbon accrual. Overall, the soil carbon sequestration in the temperate grassland is affected by the grazing regime that is applied, and grazing can be altered to improve soil carbon sequestration in the temperate steppe.

  13. Improved grazing management may increase soil carbon sequestration in temperate steppe

    NASA Astrophysics Data System (ADS)

    Chen, Wenqing; Huang, Ding; Liu, Nan; Zhang, Yingjun; Badgery, Warwick B.; Wang, Xiaoya; Shen, Yue

    2015-07-01

    Different grazing strategies impact grassland plant production and may also regulate the soil carbon formation. For a site in semiarid temperate steppe, we studied the effect of combinations of rest, high and moderate grazing pressure over three stages of the growing season, on the process involved in soil carbon sequestration. Results show that constant moderate grazing (MMM) exhibited the highest root production and turnover accumulating the most soil carbon. While deferred grazing (RHM and RMH) sequestered less soil carbon compared to MMM, they showed higher standing root mass, maintained a more desirable pasture composition, and had better ability to retain soil N. Constant high grazing pressure (HHH) caused diminished above- and belowground plant production, more soil N losses and an unfavorable microbial environment and had reduced carbon input. Reducing grazing pressure in the last grazing stage (HHM) still had a negative impact on soil carbon. Regression analyses show that adjusting stocking rate to ~5SE/ha with ~40% vegetation utilization rate can get the most carbon accrual. Overall, the soil carbon sequestration in the temperate grassland is affected by the grazing regime that is applied, and grazing can be altered to improve soil carbon sequestration in the temperate steppe.

  14. Improved grazing management may increase soil carbon sequestration in temperate steppe

    PubMed Central

    Chen, Wenqing; Huang, Ding; Liu, Nan; Zhang, Yingjun; Badgery, Warwick B.; Wang, Xiaoya; Shen, Yue

    2015-01-01

    Different grazing strategies impact grassland plant production and may also regulate the soil carbon formation. For a site in semiarid temperate steppe, we studied the effect of combinations of rest, high and moderate grazing pressure over three stages of the growing season, on the process involved in soil carbon sequestration. Results show that constant moderate grazing (MMM) exhibited the highest root production and turnover accumulating the most soil carbon. While deferred grazing (RHM and RMH) sequestered less soil carbon compared to MMM, they showed higher standing root mass, maintained a more desirable pasture composition, and had better ability to retain soil N. Constant high grazing pressure (HHH) caused diminished above- and belowground plant production, more soil N losses and an unfavorable microbial environment and had reduced carbon input. Reducing grazing pressure in the last grazing stage (HHM) still had a negative impact on soil carbon. Regression analyses show that adjusting stocking rate to ~5SE/ha with ~40% vegetation utilization rate can get the most carbon accrual. Overall, the soil carbon sequestration in the temperate grassland is affected by the grazing regime that is applied, and grazing can be altered to improve soil carbon sequestration in the temperate steppe. PMID:26137980

  15. Improved grazing management may increase soil carbon sequestration in temperate steppe.

    PubMed

    Chen, Wenqing; Huang, Ding; Liu, Nan; Zhang, Yingjun; Badgery, Warwick B; Wang, Xiaoya; Shen, Yue

    2015-01-01

    Different grazing strategies impact grassland plant production and may also regulate the soil carbon formation. For a site in semiarid temperate steppe, we studied the effect of combinations of rest, high and moderate grazing pressure over three stages of the growing season, on the process involved in soil carbon sequestration. Results show that constant moderate grazing (MMM) exhibited the highest root production and turnover accumulating the most soil carbon. While deferred grazing (RHM and RMH) sequestered less soil carbon compared to MMM, they showed higher standing root mass, maintained a more desirable pasture composition, and had better ability to retain soil N. Constant high grazing pressure (HHH) caused diminished above- and belowground plant production, more soil N losses and an unfavorable microbial environment and had reduced carbon input. Reducing grazing pressure in the last grazing stage (HHM) still had a negative impact on soil carbon. Regression analyses show that adjusting stocking rate to ~5SE/ha with ~40% vegetation utilization rate can get the most carbon accrual. Overall, the soil carbon sequestration in the temperate grassland is affected by the grazing regime that is applied, and grazing can be altered to improve soil carbon sequestration in the temperate steppe. PMID:26137980

  16. Nutritional management of grazing beef cows.

    PubMed

    Mathis, Clay P; Sawyer, Jason E

    2007-03-01

    In grazing operations, forage quality and availability are sometimes limited, and cattle are unable to consume enough nutrients from pasture forage to fulfill requirements. During such situations, supplemental or replacement feeding is necessary to meet production goals. A fundamental understanding of ruminant nutrition and forage management is helpful in deciding which feed or supplement type (ie, energy versus protein) best fits the goals of a specific beef production system. It is important to choose a delivery method and supplement form that provide the targeted amount of desired nutrients to each animal in the herd and that minimize input costs. The objective of this article is to serve as a resource for veterinarians as they provide nutritional management support to beef cow producers. PMID:17382837

  17. Spatial variation in spoil and vegetative characteristics of pastures on reclaimed surface mined land

    SciTech Connect

    Teutsch, C.D.; Collins, M.; Ditsch, D.C.

    1999-07-01

    Kentucky has large areas of reclaimed surface mined land that could provide grazing for livestock. Research is needed to determine optimal stocking densities and to evaluate the sustainability of such grazing systems for this region. A long-term grazing study was initiated in 1997 on 151 ha of reclaimed land near Chavies, KY to determine spatial and temporal variation with stocking densities of 0, 0.28, 0.42, or 0.83 beef cow-calf units/ha. Global Positioning System and GIS technologies were used to establish pasture boundaries, locate permanent sampling markers at a density of 1 per 0.4 ha, and interpolate maps of physical, spoil, and vegetable pasture characteristics. Herbage and spoil samples were collected around the permanent markers in May of 1997. Stepwise regression was used to determine factors affecting the vegetative characteristics of the sites. Biomass density ranged from 0 to 2500 kg/ha with a mean of 570 kg/ha. Factors affecting biomass included legume and weed proportions in the sward, grazing activity, soil potassium, elevation, and potential acidity, cumulatively accounting for 32% of the variation. Ground cover ranged from 10 to 100% with an average of 74%. Soil pH, potassium, and grass in the sward accounted for 14% of the variation in ground cover. Legumes made up 0 to 61% of the sward with a mean of 13% over the pasture area. Variables affecting the amount of legume in the sward included biomass density, slope, elevation, pH, and stocking density, together accounting for 21% of the variation. Spatial variation in the physical, spoil, and vegetative characteristics of the pastures was large. Overall, regression accounted for a limited amount of the variation in the vegetative characteristics of the site indicating that other important variables exist.

  18. Controlling herbaceous competition in pasture planted with loblolly pine seedlings. Forest Service research note

    SciTech Connect

    Haywood, J.D.

    1995-09-01

    Three treatments designed to control herbaceous vegetation competing with loblolly pine (Pinus taeda L.) seedlings planted in grazed and ungrazed pasture were tested. Effects of the treatments on seedling survival and growth during the first 3 years after planting were determined. The treatments were directed application of herbicides (glyphosate in the first 2 years and hexazinone in the third year), rotary mowing, and mulching with pine straw around individual pine seedlings.

  19. Discerning the cows from the pasture when determining annual NEE and carbon budget

    NASA Astrophysics Data System (ADS)

    Ammann, Christof; Felber, Raphael; Neftel, Albrecht

    2015-04-01

    The CO2 exchange of ecosystems and the resulting annual net ecosystem exchange (NEE) and total carbon budget (soil carbon sequestration) is commonly investigated using the eddy covariance (EC) technique. For the carbon budget of managed ecosystems also the import and export of organic carbon has to be taken into account. Grazed pasture systems represent a special challenge because their respiration can considerably contribute to the measured CO2 flux, but this contribution depends on the spatial distribution of the cows relative to the footprint and thus is variable in time. This has implications for the gap filling of CO2 flux time series necessary to determine annual NEE. In few existing studies two procedures have been suggested to determine the NEE of grazed pasture: (a) discarding all cases with cows in the footprint and gap-filling the remaining dataset; (b) treating the cow respiration as part of total ecosystem respiration and gap fill the entire flux dataset including cow contributions. Both approaches rely on idealized assumptions and have limitations. In our study we evaluated and compared the two approaches (for the first time to our knowledge) for a grazed pasture in Switzerland. For this purpose, the grazing cows were equipped with GPS sensors to monitor their position relative to the flux footprint. We found that the resulting annual NEE strongly depends on the flux data selection (e.g. u* filtering) and the applied gap filling procedure. Using an optimized procedure, the annual NEE with approach (b) was several times larger than the result of approach (a), but the difference agreed fairly well with independent estimates of cow respiration. Necessary assumptions and requirements of the two approaches for the determination of the pasture carbon budget will be discussed.

  20. Intensive soil organic carbon losses by degradation of alpine Kobresia pasture on the Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Schleuss, Per-Marten; Heitkamp, Felix; Seeber, Elke; Spielvogel, Sandra; Miehe, Georg; Guggenberger, Georg; Kuzyakov, Yakov

    2015-04-01

    Kobresia grasslands of the Tibetan Plateau cover an area of ca. 450,000 km2. They are of high global and regional importance as they store large amounts of carbon (C) and nitrogen (N) and provide food for grazing animals. However, intensive grassland degradation in recent decades destroyed mainly the upper root-mat/soil horizon. This has dramatic consequences for SOC storage against the background of climate change and further grazing pressure. We investigated the impact of pasture degradation on SOC storage and hypothesized that SOC stocks strongly decreased due to a reduction of C-input by roots as consequence of vegetation cover loss by overgrazing, SOM decomposition and soil erosion. We selected a sequence of six degradation stages (DS1-6). As initial trigger of grassland degradation, the high grazing pressure reduces the ability of Kobresia pastures to recover from disturbances (e.g. by freezing and drying events, herbivory, trampling). Once the root mats are destroyed, the occurring root-mat cracks increase due to soil erosion, SOC decomposition and trampling activities of livestock. The SOC stocks and contents decreased along the degradation sequence from intact to highly disturbed stages. Carbon stocks declined from intact Kobresia root mats (DS1) to bare soil patches (DS6) by about 70%. The thickness of the upper soil horizons strongly declined from DS1 to DS6. Considering the bare soil patches (DS6) on average 10 cm of the most fertile topsoil were removed. This clearly suggests that soil erosion strongly contributed to SOC losses, especially from topsoil with highest SOC contents. A strong decrease of the vegetation cover (mainly K. pygmaea) demonstrated that soil degradation also resulted in die-back of K. pygmaea. Consequently, root biomass decreased along the degradation sequence (DS1-2 > DS3-4 > DS5-6), indicating lower belowground C input from roots. We found decreasing δ13C values with increasing degradation stages within the upper 20 cm of soil

  1. Dairy heifers benefit from the presence of an experienced companion when learning how to graze.

    PubMed

    Costa, J H C; Costa, W G; Weary, D M; Machado Filho, L C P; von Keyserlingk, M A G

    2016-01-01

    Pasture remains important on many dairy farms, but the age of first contact with pasture varies depending on the month of birth, weaning age, and farm management. Regardless of age, naïve dairy heifers must learn to graze when first introduced to pasture. This study investigated whether being grouped with experienced dairy cows would affect the development of grazing behaviors. Sixty-three Holstein heifers (mean ± SD 14.2 ± 1.3 mo; 546 ± 60.7 kg) and 21 dry Holstein cows (2.6 ± 0.8 lactations; 751 ± 53.9 kg) were assigned into 7 groups of 12 animals (3 dry cows and 9 naïve heifers), and each was divided and assigned to an experienced (3 cows and 3 heifers) and nonexperienced (6 heifers) sub-group. Sub-groups were introduced to pasture in different paddocks without visual contact with any other cattle. No difference was found in the time after introduction to the paddock for heifers to first attempt to nibble grass [experienced: 0:23 (0:17-0:43) vs. nonexperienced 0:40 (0:35-0:46); median (quartile 1 - quartile 3), h:mm]. However, heifers grouped with experienced cows showed a shorter latency to begin grazing [experienced: 0:47 (0:28-00:52) vs. nonexperienced 2:13 (1:25-2:30)]. During the first hour after introduction to pasture, heifers in the experienced treatment showed fewer stomping events [experienced: 2.5 (1.25-4) vs. nonexperienced: 6.5 (4-8)] and vocalized less often [experienced: 3.5 (1.25-5.75) vs. nonexperienced: 7 (5-8.75)]. After this initial period, animals in both subgroups began to graze normally; treatments did not differ in grazing behaviors over the 3-d observation period. These results indicate that grouping heifers with pasture-experienced cows improves grazing behavior of dairy heifers in the first hours following introduction to pasture. PMID:26547655

  2. Spatial distribution of nitrogen on grazed karst landscapes.

    PubMed

    Boyer, D G; Alloush, G A

    2001-11-27

    The impact on water quality by agricultural activity in karst terrain is an important consideration for resource management within the Appalachian region. Karst areas comprise about 18% of the region"s land area. An estimated one-third of the region"s farms, cattle, and agricultural market value are located on karst terrain. Mean nitrate concentrations in several karst springs in southeastern West Virginia exhibit a strong linear relationship with the percentage of agriculture land cover. Development of best management practices for efficient nitrogen (N) use and reduction of outflow of N to water from karst areas requires knowledge about N dynamics on those landscapes. Water extractable NO3-N and NH4-N were measured along transects at four soil depths in two grazed sinkholes and one wooded sinkhole. Distribution of soil NO3-N and NH4-N were related to frequency of animal presence and to topographic and hydrologic redistribution of soil and fecal matter in the grazed sinkholes. Karst pastures are characterized by under drainage and funneling of water and contaminants to the shallow aquifer. Control of NO3-N leaching from karst pasture may depend on management strategies that change livestock grazing behavior in sinkholes and reduce the opportunity for water and contaminants to quickly reach sinkhole drains.

  3. ASAS Centennial Paper: utilization of pasture and forages by ruminants: a historical perspective.

    PubMed

    Burns, J C

    2008-12-01

    Pastures, forages, and grasslands dominate the landscape across the United States and support a large ruminant population that supplies the nation with value-added animal products. A historical perspective is presented of the innovations as they occurred in the Journal of Animal Science over the past 100 yr in pasture and forage research. Consideration was given to both animal and pasture perspectives. Areas given consideration from the animal perspective were schemes for feedstuff analysis, experimental design and statistics, forage sample preservation, indirect methods of measuring intake and digestion, TDN and energy, nutritive value, harvested forage, and innovations in the grazing environment. Areas given consideration from the forage perspective were a framework for forage-animal interface research, determining pasture yield, choice of stocking method, grazing management, partitioning of forage DM, near-infrared reflectance spectroscopy technology, antiquality constituents, and forage sample preservation. Finally, the importance was discussed of applying research results from the forage-animal interface to general ruminant nutrition research beyond the interface that is focused on altered diets.

  4. Sound management may sequester methane in grazed rangeland ecosystems.

    PubMed

    Wang, Chengjie; Han, Guodong; Wang, Shiping; Zhai, Xiajie; Brown, Joel; Havstad, Kris M; Ma, Xiuzhi; Wilkes, Andreas; Zhao, Mengli; Tang, Shiming; Zhou, Pei; Jiang, Yuanyuan; Lu, Tingting; Wang, Zhongwu; Li, Zhiguo

    2014-03-24

    Considering their contribution to global warming, the sources and sinks of methane (CH4) should be accounted when undertaking a greenhouse gas inventory for grazed rangeland ecosystems. The aim of this study was to evaluate the mitigation potential of current ecological management programs implemented in the main rangeland regions of China. The influences of rangeland improvement, utilization and livestock production on CH4 flux/emission were assessed to estimate CH4 reduction potential. Results indicate that the grazed rangeland ecosystem is currently a net source of atmospheric CH4. However, there is potential to convert the ecosystem to a net sink by improving management practices. Previous assessments of capacity for CH4 uptake in grazed rangeland ecosystems have not considered improved livestock management practices and thus underestimated potential for CH4 uptake. Optimal fertilization, rest and light grazing, and intensification of livestock management contribute mitigation potential significantly.

  5. Traditional cattle grazing in a mosaic alkali landscape: effects on grassland biodiversity along a moisture gradient.

    PubMed

    Török, Péter; Valkó, Orsolya; Deák, Balázs; Kelemen, András; Tóthmérész, Béla

    2014-01-01

    Extensively managed pastures are of crucial importance in sustaining biodiversity both in local- and landscape-level. Thus, re-introduction of traditional grazing management is a crucial issue in grassland conservation actions worldwide. Traditional grazing with robust cattle breeds in low stocking rates is considered to be especially useful to mimic natural grazing regimes, but well documented case-studies are surprisingly rare on this topic. Our goal was to evaluate the effectiveness of traditional Hungarian Grey cattle grazing as a conservation action in a mosaic alkali landscape. We asked the following questions: (i) How does cattle grazing affect species composition and diversity of the grasslands? (ii) What are the effects of grazing on short-lived and perennial noxious species? (iii) Are there distinct effects of grazing in dry-, mesophilous- and wet grassland types? Vegetation of fenced and grazed plots in a 200-ha sized habitat complex (secondary dry grasslands and pristine mesophilous- and wet alkali grasslands) was sampled from 2006-2009 in East-Hungary. We found higher diversity scores in grazed plots compared to fenced ones in mesophilous- and wet grasslands. Higher cover of noxious species was typical in fenced plots compared to their grazed counterparts in the last year in every studied grassland type. We found an increasing effect of grazing from the dry- towards the wet grassland types. The year-to-year differences also followed similar pattern: the site-dependent effects were the lowest in the dry grassland and an increasing effect was detected along the moisture gradient. We found that extensive Hungarian Grey cattle grazing is an effective tool to suppress noxious species and to create a mosaic vegetation structure, which enables to maintain high species richness in the landscape. Hungarian Grey cattle can feed in open habitats along long moisture gradient, thus in highly mosaic landscapes this breed can be the most suitable livestock type.

  6. Impacts of rotational grazing and riparian buffers on physicochemical and biological characteristicsof southeastern Minnesota, USA, streams.

    PubMed

    Sovell, L A; Vondracek, B; Frost, J A; Mumford, K G

    2000-12-01

    We assessed the relationship between riparian management and stream quality along five southeastern Minnesota streams in 1995 and 1996. Specifically, we examined the effect of rotationally and continuously grazed pastures and different types of riparian buffer strips on water chemistry, physical habitat, benthic macroinvertebrates, and fish as indicators of stream quality. We collected data at 17 sites under different combinations of grazing and riparian management, using a longitudinal design on three streams and a paired watershed design on two others. Continuous and rotational grazing were compared along one longitudinal study stream and at the paired watershed. Riparian buffer management, fenced trees (wood buffer), fenced grass, and unfenced rotationally grazed areas were the focus along the two remaining longitudinal streams. Principal components analysis (PCA) of water chemistry, physical habitat, and biotic data indicated a local management effect. The ordinations separated continuous grazing from sites with rotational grazing and sites with wood buffers from those with grass buffers or rotationally grazed areas. Fecal coliform and turbidity were consistently higher at continuously grazed than rotationally grazed sites. Percent fines in the streambed were significantly higher at sites with wood buffers than grass and rotationally grazed areas, and canopy cover was similar at sites with wood and grass buffers. Benthic macroinvertebrate metrics were significant but were not consistent across grazing and riparian buffer management types. Fish density and abundance were related to riparian buffer type, rather than grazing practices. Our study has potentially important implications for stream restoration programs in the midwestern United States. Our comparisons suggest further consideration and study of a combination of grass and wood riparian buffer strips as midwestern stream management options, rather than universally installing wood buffers in every instance

  7. Traditional Cattle Grazing in a Mosaic Alkali Landscape: Effects on Grassland Biodiversity along a Moisture Gradient

    PubMed Central

    Török, Péter; Valkó, Orsolya; Deák, Balázs; Kelemen, András; Tóthmérész, Béla

    2014-01-01

    Extensively managed pastures are of crucial importance in sustaining biodiversity both in local- and landscape-level. Thus, re-introduction of traditional grazing management is a crucial issue in grassland conservation actions worldwide. Traditional grazing with robust cattle breeds in low stocking rates is considered to be especially useful to mimic natural grazing regimes, but well documented case-studies are surprisingly rare on this topic. Our goal was to evaluate the effectiveness of traditional Hungarian Grey cattle grazing as a conservation action in a mosaic alkali landscape. We asked the following questions: (i) How does cattle grazing affect species composition and diversity of the grasslands? (ii) What are the effects of grazing on short-lived and perennial noxious species? (iii) Are there distinct effects of grazing in dry-, mesophilous- and wet grassland types? Vegetation of fenced and grazed plots in a 200-ha sized habitat complex (secondary dry grasslands and pristine mesophilous- and wet alkali grasslands) was sampled from 2006–2009 in East-Hungary. We found higher diversity scores in grazed plots compared to fenced ones in mesophilous- and wet grasslands. Higher cover of noxious species was typical in fenced plots compared to their grazed counterparts in the last year in every studied grassland type. We found an increasing effect of grazing from the dry- towards the wet grassland types. The year-to-year differences also followed similar pattern: the site-dependent effects were the lowest in the dry grassland and an increasing effect was detected along the moisture gradient. We found that extensive Hungarian Grey cattle grazing is an effective tool to suppress noxious species and to create a mosaic vegetation structure, which enables to maintain high species richness in the landscape. Hungarian Grey cattle can feed in open habitats along long moisture gradient, thus in highly mosaic landscapes this breed can be the most suitable livestock type

  8. Spatial Simulation of the Dynamics of Establishment of Secondary Forest in Abandoned Pasture in the Central Amazon

    NASA Astrophysics Data System (ADS)

    Rebel, K. T.; Riha, S. J.; Rondon, M. A.; Feldpausch, T. R.; Fernandes, E. C.

    2001-05-01

    In the Amazon, approximately 35 million hectares of primary forest that was converted to pasture is now being abandoned. This represents about 70% of all pastureland that was previously established. The dynamics of reconversion of this land to secondary forest is of interest because the length of time required for pasture to convert to secondary forest will impact net primary productivity and the amount of carbon being stored on abandoned pastures. In addition, the length of time required for pasture to convert to secondary forest may depend on the size of the pasture, whether it is surrounded by primary or secondary forest, and on pasture productivity at the time of abandonment. Pasture productivity at the time of abandonment will depend primarily on the age structure of the pasture grasses and on weediness, which are influenced by grazing and fire history. Also, an understanding of the dynamics of conversion of pastureland to forest can serve as the basis for management strategies to inhibit pasture conversion. A spatial, dynamic model of the conversion of pasture to secondary forest was developed using the PCRaster Dynamic Modeling Package. This software provides a computer language specially developed for modeling temporal and spatial processes in a GIS, and is well suited for the development of ecological, dynamic models. The model of pasture conversion is implemented for the central Amazon. We assume that succession involves only three plant types: pasture grass, weeds and woody plants. The pasture grass is parameterized for Brachiaria (brizantha, humidicola), the weeds for Borreria and Rolandra, and the woody plants for Vismia spp. The model uses a 1m x 1m grid and 2-month time step. Each initial plant and each surviving propagule is referred to as a plant and only occupies one grid cell. A number of values are calculated for each grid cell for each time-step. These include whether vegetation is present and, if so, which species, the age of the species, the

  9. Herbivory and Competition of Tibetan Steppe Vegetation in Winter Pasture: Effects of Livestock Exclosure and Plateau Pika Reduction.

    PubMed

    Harris, Richard B; Wenying, Wang; Badinqiuying; Smith, Andrew T; Bedunah, Donald J

    2015-01-01

    Rangeland degradation has been identified as a serious concern in alpine regions of western China on the Qinghai-Tibetan plateau (QTP). Numerous government-sponsored programs have been initiated, including many that feature long-term grazing prohibitions and some that call for eliminating pastoralism altogether. As well, government programs have long favored eliminating plateau pikas (Ochotona curzoniae), assumed to contribute to degraded conditions. However, vegetation on the QTP evolved in the presence of herbivory, suggesting that deleterious effects from grazing are, to some extent, compensated for by reduced plant-plant competition. We examined the dynamics of common steppe ecosystem species as well as physical indicators of rangeland stress by excluding livestock and reducing pika abundance on experimental plots, and following responses for 4 years. We established 12 fenced livestock exclosures within pastures grazed during winter by local pastoralists, and removed pikas on half of these. We established paired, permanent vegetation plots within and outside exclosures and measured indices of erosion and biomass of common plant species. We observed modest restoration of physical site conditions (reduced bare soil, erosion, greater vegetation cover) with both livestock exclusion and pika reduction. As expected in areas protected from grazing, we observed a reduction in annual productivity of plant species avoided by livestock and assumed to compete poorly when protected from grazing. Contrary to expectation, we observed similar reductions in annual productivity among palatable, perennial graminoids under livestock exclusion. The dominant grass, Stipa purpurea, displayed evidence of density-dependent growth, suggesting that intra-specific competition exerted a regulatory effect on annual production in the absence of grazing. Complete grazing bans on winter pastures in steppe habitats on the QTP may assist in the recovery of highly eroded pastures, but may not

  10. Herbivory and Competition of Tibetan Steppe Vegetation in Winter Pasture: Effects of Livestock Exclosure and Plateau Pika Reduction

    PubMed Central

    Harris, Richard B.; Wenying, Wang; Badinqiuying; Smith, Andrew T.

    2015-01-01

    Rangeland degradation has been identified as a serious concern in alpine regions of western China on the Qinghai-Tibetan plateau (QTP). Numerous government-sponsored programs have been initiated, including many that feature long-term grazing prohibitions and some that call for eliminating pastoralism altogether. As well, government programs have long favored eliminating plateau pikas (Ochotona curzoniae), assumed to contribute to degraded conditions. However, vegetation on the QTP evolved in the presence of herbivory, suggesting that deleterious effects from grazing are, to some extent, compensated for by reduced plant-plant competition. We examined the dynamics of common steppe ecosystem species as well as physical indicators of rangeland stress by excluding livestock and reducing pika abundance on experimental plots, and following responses for 4 years. We established 12 fenced livestock exclosures within pastures grazed during winter by local pastoralists, and removed pikas on half of these. We established paired, permanent vegetation plots within and outside exclosures and measured indices of erosion and biomass of common plant species. We observed modest restoration of physical site conditions (reduced bare soil, erosion, greater vegetation cover) with both livestock exclusion and pika reduction. As expected in areas protected from grazing, we observed a reduction in annual productivity of plant species avoided by livestock and assumed to compete poorly when protected from grazing. Contrary to expectation, we observed similar reductions in annual productivity among palatable, perennial graminoids under livestock exclusion. The dominant grass, Stipa purpurea, displayed evidence of density-dependent growth, suggesting that intra-specific competition exerted a regulatory effect on annual production in the absence of grazing. Complete grazing bans on winter pastures in steppe habitats on the QTP may assist in the recovery of highly eroded pastures, but may not

  11. Effect of stocking rate on pasture production, milk production, and reproduction of dairy cows in pasture-based systems.

    PubMed

    Macdonald, K A; Penno, J W; Lancaster, J A S; Roche, J R

    2008-05-01

    Ninety-four cows were randomly allocated to 1 of 5 stocking rates (2.2, 2.7, 3.1, 3.7, and 4.3 cows/ha) in a completely randomized design for 3 years. Herds were seasonal calving, with only minor differences in grazing management to optimize the profitability of each stocking rate (SR). Pasture production and quality data, milk and milk component data, and reproduction data were collected, averaged for SR treatment, and linear and quadratic contrasts on SR were evaluated. In addition, the Wilmink exponential model (y(t) = a + b x e((-0.05t) )+ c x t) was fitted to milk yield within lactation, and the parameters were averaged by SR treatment and analyzed as above. The median variation explained by the function for individual lactations was 84%. The amount of pasture grown tended to increase, and the quality of the pasture on offer increased linearly with increasing SR, reducing some of the negative impact of SR on the availability of pasture per cow. Milk production per cow declined linearly with increasing SR, although there was a tendency for most production variables to decline quadratically, with the negative effect of SR declining with increasing SR. The effect on milk production per cow was primarily because of a lower peak milk yield and a greater post-peak decline (less persistent milk profile), although a decline in lactation length with increasing SR was responsible for 24% of the effect of SR on milk yield. Milk production per hectare increased linearly with increasing SR, and there was only a small difference (approximately 3%/cow per ha) in the efficiency of converting feed dry matter into milk energy. Stocking rate did not affect reproductive success. The data are consistent with the need for a more robust measure of SR than cows per hectare because farms will differ in the genetic merit of their cows and in the potential to produce pasture. We introduce the concept of a comparative SR, whereby the carrying capacity of the farm is defined by the BW of

  12. Grazing management as it affects nutrition, animal production and economics of beef production.

    PubMed

    Parsons, S D; Allison, C D

    1991-03-01

    Until recently, the nutritional fate of the grazing animal has been largely ignored by both animal and range scientists despite the economic dependence of the extensive livestock industry on nutrition from grass. Of the three factors that can be manipulated to improve profit gross margin per animal, is one that is directly affected by nutrition and, hence, grazing management. The relationship between economics and grazing management may be summarized as: Gross margin = f(Animal Performance); Animal Performance = f(nutrition); Nutrition = f(grazing). Economical beef production must consider the needs of the animal and the forage plant at the same time. The health of the sward must be maintained while improving individual animal performance and simultaneously increasing stocking rate. Generally, plants that have been defoliated require a period of recovery before again being grazed. A sward is kept in a vigorous state by preventing repetitive defoliation at the one extreme, and avoiding excessive shading (mature growth) of photosynthetic material at the other. This state is best achieved where livestock grazing is controlled. For any individual paddock, periods of grazing are followed by periods that allow adequate physiologic recovery of the plants. A grazing regimen that keeps the plant in a healthy state is fortuitously also well suited to the nutritional requirements of the animal. Animals on overgrazed pastures are likely to suffer from inadequate feed intake because of deficiencies in feed quantity. Conversely, on over-rested pastures, intake deficiency results from paucity in feed quality. On most unmanaged ranges, overgrazed and over-rested plants are likely to be found side by side. By controlling duration of the rest period as well as duration of the grazing period through pasture subdivision, requirements of both the plant and the animal can be met. With artificially high economic demands placed on animal production, some form of supplementation is

  13. Fecal coliform concentrations in runoff from a grazed, reclaimed surface mine

    SciTech Connect

    Boyer, D.G.; Perry, H.D.

    1987-10-01

    The relatively scarcity of flat or moderately sloping land in Central Appalachia make reclaimed surface mined lands attractive for agricultural uses. A reclaimed surface coal mine in southern West Virginia was placed under grazing management during the 1984 and 1985 grown seasons. Discharge was collected from summer-grazed watersheds of about 2.8 ha and 8.9 ha and analyzed, by the membrane-filtration method, for fecal coliforms (FC). Prior to grazing in 1984, FC counts were < 200/100 ml. During the grazing season, FC ranged from < 0/100 ml to > 1000/100 ml in 1984 and from 0/100 ml to > 2500/100 ml in 1985. FC counts remained high during warm periods for several months after grazing ceased. It was concluded that the bacteriological quality of receiving streams was impacted by grazing the reclaimed area and recommended standards for point sources were often exceeded; however, the FC counts did not appear to be any greater than what would have been expected from grazed, undisturbed areas. Reclaimed surface mines areas in Appalachia have the potential to be a valuable flat land resource and grazing appears to be an alternative post mine land use that affects bacteriological water quality in a similar manner as natural pastures. However, good management practices may be necessary to avoid bacterial contamination of adjacent bodies of water.

  14. A Case Study of Behaviour and Performance of Confined or Pastured Cows During the Dry Period.

    PubMed

    Black, Randi A; Krawczel, Peter D

    2016-01-01

    The objectives of this study were to determine the effect of the dry cow management system (pasture or confined) on: (1) lying behaviour and activity; (2) feeding and heat stress behaviours; (3) intramammary infections, postpartum. Non-lactating Holstein cows were assigned to either deep-bedded, sand freestalls ( n = 14) or pasture ( n = 14) using rolling enrollment. At dry-off, cows were equipped with an accelerometer to determine daily lying time (h/d), lying bouts (bouts/d), steps (steps/d) and divided into periods: far-off (60 to 15 d prepartum), close-up (14 to 1 d prepartum), calving (calving date) and postpartum (1 to 14 d postpartum). Respiration rates were recorded once weekly from dry off to calving from 1300 to 1500 h. Feeding displacements were defined as one cow successfully displacing another from the feed bunk and were recorded once per week during the 2 h period, immediately after feeding at 800 h. Pastured cows were fed a commercial dry cow pellet during far-off and total mixed ration during close-up, with free access to hay and grazing. Freestall housed cows were fed a total mixed ration at far-off and close-up. Cows housed in freestalls were moved to a maternity pen with a mattress at commencement of labour. Pastured cows calved in pasture. After calving, all cows were commingled in a pen identical to the freestall housing treatment. Cows housed in freestalls laid down for longer during far-off and close-up periods, had fewer lying bouts during the calving period and took fewer steps throughout the study period when compared to pastured cows. Freestall housed cows experienced more displacements after feeding than did pastured cows. Respiration rates increased with an increasing temperature humidity index, more in pastured cows than in freestall housed cows. Pastured cows altered their lying behaviour and activity, suggesting a shift in time budget priorities between pastured and confined dry cows. Pastured cows also experienced less aggression

  15. The carbon footprint of pasture-based milk production: can white clover make a difference?

    PubMed

    Yan, M-J; Humphreys, J; Holden, N M

    2013-02-01

    Carbon footprint (CF) calculated by life cycle assessment (LCA) was used to compare greenhouse gas emissions from pasture-based milk production relying mainly on (1) fertilizer N (FN), or (2) white clover (WC). Data were sourced from studies conducted at Solohead Research Farm in Ireland between 2001 and 2006. Ten FN pastures stocked between 2.0 and 2.5 livestock units (LU)/ha with fertilizer N input between 180 and 353 kg/ha were compared with 6 WC pastures stocked between 1.75 and 2.2 LU/ha with fertilizer N input between 80 and 99 kg/ha. The WC-based system had 11 to 23% lower CF compared with FN (average CF was 0.86 to 0.87 and 0.97 to 1.13 kg of CO(2)-eq/kg of energy-corrected milk, respectively, 91% economic allocation). Emissions of both N(2)O and CO(2) were lower in WC, whereas emissions of CH(4) (per kg of energy-corrected milk) were similar in both systems. Ratio sensitivity analysis indicated that the difference was not caused by error due to modeling assumptions. Replacing fertilizer N by biological nitrogen fixation could lower the CF of pasture-based milk production.

  16. Optimising stocking rate and grazing management to enhance environmental and production outcomes for native temperate grasslands

    NASA Astrophysics Data System (ADS)

    Badgery, Warwick; Zhang, Yingjun; Huang, Ding; Broadfoot, Kim; Kemp, David; Mitchell, David

    2015-04-01

    Stocking rate and grazing management can be altered to enhance the sustainable production of grasslands but the relative influence of each has not often been determined for native temperate grasslands. Grazing management can range from seasonal rests through to intensive rotational grazing involving >30 paddocks. In large scale grazing, it can be difficult to segregate the influence of grazing pressure from the timing of utilisation. Moreover, relative grazing pressure can change between years as seasonal conditions influence grassland production compared to the relative constant requirements of animals. This paper reports on two studies in temperate native grasslands of northern China and south eastern Australia that examined stocking rate and regionally relevant grazing management strategies. In China, the grazing experiment involved combinations of a rest, moderate or heavy grazing pressure of sheep in spring, then moderate or heavy grazing in summer and autumn. Moderate grazing pressure at 50% of the current district average, resulted in the better balance between maintaining productive and diverse grasslands, a profitable livestock system, and mitigation of greenhouse gases through increased soil carbon, methane uptake by the soil, and efficient methane emissions per unit of weight gain. Spring rests best maintained a desirable grassland composition, but had few other benefits and reduced livestock productivity due to lower feed quality from grazing later in the season. In Australia, the grazing experiment compared continuous grazing to flexible 4- and 20-paddock rotational grazing systems with sheep. Stocking rates were adjusted between systems biannually based on the average herbage mass of the grassland. No treatment degraded the perennial pasture composition, but ground cover was maintained at higher levels in the 20-paddock system even though this treatment had a higher stocking rate. Overall there was little difference in livestock production (e.g. kg

  17. Effect of application of fluidized bed combustion residue to reclaimed mine pastures on forage yield, composition, animal performance, and mineral status

    SciTech Connect

    Smedley, K.O.

    1985-01-01

    Reclaimed surface mined soils in Appalachia are typically infertile and must be amended for optimum vegetative growth. Fluidized bed combustion residue (FBCR) has high levels of Ca, S, Zn, Fe, and Al, and 50% of the neutralizing capacity of limestone. Three treatments were applied to three capacity of limestone. Three treatments were applied to three replicated 0.81 ha reclaimed mine pastures: (A) control (no amendment), (B) 6760 kg FBCR/ha, and (C) 3380 kg limestone/ha. Based on forage availability, six steers were rotationally grazed on pastures receiving each treatment. Steers were weighed and blood samples collected at 14-d intervals and all animals were sacrificed for tissue sampling at the end of the 114-d trial. B and C increased soil pH above control levels. Forage yield and steer gain were not significantly affected by treatment. Forage samples collected during the trial indicated that B and C amendments elevated forage ash, Ca, Mg, S, Cu, and Ca:P ratio and depressed cellulose and NDF. The forage sampled the following spring was lower in hemicellulose, Zn, Mn and Ni; and higher in ash, Ca, S, the Ca:P ratio in the B and C pastures. Mean serum mineral levels of steers were not affected by pasture treatment. The blood packed cell volume was higher in cattle grazing pastures. Liver levels of Fe, Mn, Ni, and Na and bile levels of Mn were depressed in cattle grazing B and C and serum was at deficiency levels and was not detectable in bile, regardless of treatment. Kidney levels of Ca, Mg and P were higher, hair Zn was higher, rib Cr and long bone Cd levels were lower in animals grazing the pastures. This study suggests that FBCR amendment enhances nutrient quality of forage and minerals status of animals at least as well as limestone application to acidic reclaimed mine pastures.

  18. Cadmium concentrations in new zealand pastures: relationships to soil and climate variables.

    PubMed

    Reiser, René; Simmler, Michael; Portmann, Denise; Clucas, Lynne; Schulin, Rainer; Robinson, Brett

    2014-05-01

    Cadmium (Cd) is a nonessential element that occurs at above-background concentrations in many New Zealand (NZ) soils. Most of this Cd is due to the historical application of single superphosphate that was made from Nauru phosphate rock containing between 400 and 600 mg Cd kg P. Pasture Cd uptake exacerbates the entry of Cd into animal products. We sought to determine the critical environmental factors affecting Cd uptake in NZ pastures and to calculate the likely Cd intake of sheep and cattle. We tested 69 pastures throughout NZ for a range of variables, including Cd. Soil Cd and pasture Cd were positively correlated with soil P and soil concentrations of other elements found in phosphate fertilizers. We found that no single environmental variable adequately predicted pasture Cd uptake. Nevertheless, pseudo-total soil Cd and Cd extracted using a 0.05 mol L Ca(NO) solution were positively correlated with pasture Cd. Although soil pH, soil Fe, and soil Cd provided an excellent predictor of the Ca(NO)-extractable soil Cd fraction, regression models explained just 38% of the variation of the Cd concentration in pasture grasses. Incorporating the effect of pasture species composition is a crucial next step in improving these models. A calculation of the likely exposure to Cd of sheep and cattle revealed that no pastures tested resulted in sheep and cattle ingesting Cd at a rate that would result in breaching muscle-tissue food standards. For offal products, which the NZ meat industry does not sell for human consumption, food safety standards exceedence was calculated in a few cases. PMID:25602820

  19. Changes in nutrient dynamics throughout water transfers in a Tropical Forest and Pasture of Rondonia, Brazil

    NASA Astrophysics Data System (ADS)

    Piccolo, M. D.; Neill, C.; Krusche, A.; Laclau, J. P.; Cerri, C. C.

    2006-12-01

    The clearing of tropical forest in the Brazilian Amazon for cattle pasture since the 70s is a globally important land use change that has consequences for soil biogeochemical cycles. Generally, five to ten years after deforestation, pastures become degraded due to inadequate management practices. Development of strategies for restoration of low productivity pastures constitutes the main goal for Rondônia state. We analyzed the concentrations of the main nutrient of the biogeochemical cycles in three representative land uses at Fazenda Nova Vida, in central Rondônia (10o30'S, 62o30'W). The treatments were: (1) native forest; (2) pasture dominated by the forage grass Brachiaria brizantha but containing some weeds, under non- intensive management and; (3) a section of the same pasture that was subjected to tilling, replanting and fertilization (NPK + micronutrients) to eliminate weeds and improve grass productivity. Water samples from rain, throughfall, overland flow, tension lysimeter and zero-tension lysimeter (1.0 m soil depth), were collected during the rainy seasons from January to May of 2002 and 2003. The concentrations of C (DOC and DIC), inorganic-N (NH4+, NO3- and NO2-), Na+, K+, Mg2+, Ca2+, SO42- and Cl- were measured in all treatments. Rain water was dominated by the nutrients (NH4+, Na+, K+, Ca2+ and Cl-) and DOC. Forest throughfall was enriched in most of the elements. Concentrations of elements in the overland flow showed higher variations in the pasture and in the plowed pasture, however samples were not collected in forest. Soil solution waters (tension lysimeter) and lysimeter waters (zero-tension lysimeter) too had higher variations for elements concentrations in all treatments. Forest clearing for pasture and pasture submitted to tillage practices profoundly influence soil properties and, consequently, the nutrient availability in soil profiles. The soil solution composition may be indicative of altered patterns of nutrient availability in this

  20. Hydrology and Soil Erosion in Tropical Rainforests and Pasture Lands on the Atherton Tablelands, North Queensland, Australia - a rainfall simulator study

    NASA Astrophysics Data System (ADS)

    Joanne, Joanne; Ciesiolka, Cyril

    2010-05-01

    The Barron and Johnstone Rivers rise in the basaltic Atherton Tableland, North Queensland, Australia, and flow into the Coral Sea and Great Barrier Reef World Heritage Area (GBRWHA). Natural rainforest in this region was cleared for settlement in the early 20th century. Rapid decline in soil fertility during the 1940's and 50's forced landholders to turn to pasture based industries from row crop agriculture. Since then, these pasture based industries have intensified. The intensified land use has been linked to increases in sediment and nutrient levels in terrestrial runoff and identified as a major environmental threat to the GBRWHA, which has raised alarm for the tourist industry and resource managers. Studies linking land-use to pollutant discharge are often based on measurements and modelling of end of catchment measurements of water quality. Whilst such measurements can be a reasonable indicator of the effects of land use on pollutant discharge to waterways, they are often a gross assessment. This project used rainfall simulations to investigate the relationship between land use and management with sources and sinks of runoff and soil erosion within the Barron and Johnstone Rivers catchments. Rainfall simulations were conducted and pollutant loads measured in natural rainforest, as well as dairy and beef farming systems. The dairy farming systems included an effluent fed pasture, a high mineral fertilizer and supplementary irrigation farm, and a rainfed organic pasture that relied on tropical legumes and introduced grasses and returned organic material to the soil. One of the beef farming systems used a 7-10 day rotation with a low fertilizer regime (kikuyu mostly), while the other, used a long period- two paddock-rotation with no fertiliser and paspalum pastures. The rainforests were generally small isolated enclaves with a well developed shrub layer (1-3 m), and a presence of scattered, deciduous trees. Simulations were carried out on sites which were

  1. A Case Study of Behaviour and Performance of Confined or Pastured Cows During the Dry Period

    PubMed Central

    Black, Randi A.; Krawczel, Peter D.

    2016-01-01

    Simple Summary Pasture and freestall systems offer benefits and consequences during lactation but have not been investigated during the dry period. The effect of pasture or confined systems during the dry period on behaviour and milk quality was investigated. Freestall housing resulted in more resting behaviour and less locomotor activity during the dry period compared to pastured cows. At calving, freestall housed cows performed fewer lying bouts and less locomotor activity compared to pastured cows. Pasture resulted in less aggression around feeding but high respiration rates during peak heat times. Pasture during the dry period altered lying behavior, reduced feed bunk aggression and increased heat stress behaviors. Abstract The objectives of this study were to determine the effect of the dry cow management system (pasture or confined) on: (1) lying behaviour and activity; (2) feeding and heat stress behaviours; (3) intramammary infections, postpartum. Non-lactating Holstein cows were assigned to either deep-bedded, sand freestalls (n = 14) or pasture (n = 14) using rolling enrollment. At dry-off, cows were equipped with an accelerometer to determine daily lying time (h/d), lying bouts (bouts/d), steps (steps/d) and divided into periods: far-off (60 to 15 d prepartum), close-up (14 to 1 d prepartum), calving (calving date) and postpartum (1 to 14 d postpartum). Respiration rates were recorded once weekly from dry off to calving from 1300 to 1500 h. Feeding displacements were defined as one cow successfully displacing another from the feed bunk and were recorded once per week during the 2 h period, immediately after feeding at 800 h. Pastured cows were fed a commercial dry cow pellet during far-off and total mixed ration during close-up, with free access to hay and grazing. Freestall housed cows were fed a total mixed ration at far-off and close-up. Cows housed in freestalls were moved to a maternity pen with a mattress at commencement of labour. Pastured cows

  2. Pasture management controls soil organic matter stocks, properties, and biochemical functioning in Tibetan grasslands

    NASA Astrophysics Data System (ADS)

    Spielvogel, Sandra; Breidenbach, Andreas; de la Haye, Tilman; Schleuß, Per; Kuzyakov, Yakov; Guggenberger, Georg

    2016-04-01

    The Tibetan Plateau hosts the highest and largest pasture ecosystem worldwide, and provides tremendous sinks for carbon. Due to the sheer size of the of the Tibetan Plateau, feedback effects of soil organic carbon (OC) losses from inadequate grassland management are of undisputed relevance for ecosystem stability and future global change scenarios. Given the vital importance of the Tibetan steppes as global OC sinks, we combined data on OC stocks from own studies with an extensive literature review on soils developed under montane and alpine Kobresia pygmaea and Stipa grandis pastures. We calculated soil OC stocks at the Tibetan Plateau within the first 30 cm of the soil profile depending on pasture management and climate. Vertical gradients of δ13C values, neutral sugar, cutin and suberin contents, lignin phenol contents as well as microbial community composition (t-RFLP analysis, 16S rDNA und IST sequencing) and activities of six extracellular enzymes involved in the C, N, and P cycle were assessed. The depth gradients of these parameters reflected degradation processes from intact Kobresia pastures (stage 0) to pronounced degradation (bare soil; stage 5). Moderate husbandry is beneficial for the storage of OC, nitrogen (N) and other nutrients (e.g. phosphorus) for the majority of the montane grasslands of the Tibetan Plateau (i.e., Kobresia pygmaea pastures). However, Kobresia root mats originated from grazing are affected by desiccations and frost, which cause polygonal cracking and initiates soil erosion. This process is accelerated under high grazing pressure (overgrazing) that enhances root mat degradation. Increasing degradation caused by large herbivore densities resulted in an increased OC decomposition demonstrated by decreasing δ13C values. The δ13C shift towards more negative values reflects the relative enrichment of 13C depleted lignin components during OC decomposition in the strongly disturbed soil. Translocation of topsoil material into the

  3. Access to pasture for dairy cows: responses from an online engagement.

    PubMed

    Schuppli, C A; von Keyserlingk, M A G; Weary, D M

    2014-11-01

    An online engagement exercise documented the views of Canadian and U.S. participants affiliated and unaffiliated with the dairy industry on the issue of pasture access for dairy cows. A total of 414 people participated in 10 independent web forums. Providing access to more natural living conditions, including pasture, was viewed as important for the large majority of participants, including those affiliated with the dairy industry. This finding is at odds with current practice on the majority of farms in North America that provide little or no access to pasture. Participant comments showed that the perceived value of pasture access for dairy cattle went beyond the benefits of eating grass; participants cited as benefits exposure to fresh air, ability to move freely, ability to live in social groups, improved health, and healthier milk products. To accommodate the challenges of allowing pasture access on farms, some participants argued in favor of hybrid systems that provide a mixture of indoor confinement housing and grazing. Understanding the beliefs and concerns of participants affiliated and unaffiliated with the dairy industry allows for the identification of contentious topics as well as areas of agreement; this is important in efforts to better harmonize industry practices with societal expectations. PMID:25261215

  4. Tropical rain forest conversion to pasture: Changes in vegetation and soil properties

    SciTech Connect

    Reiners, W.A. ); Bouwman, A.F. ); Parsons, W.F.J. Institute of Marine and Coastal Sciences, Rugers Univ., New Brunswick, NJ ); Keller, M. )

    1994-05-01

    The effect of converting lowland tropical rainforest to pasture, and of subsequent succession of pasture lands to secondary forest, were examined in the Atlantic Zone of Costa Rica. Three replicate sites of each of four land-use types representing this disturbance-recovery sequence were sampled for changes in vegetation, pedological properties, and potential nitrogen mineralization and nitrification. The four land-use types included primary forest, actively grazed pasture (10-36 yr old), abandoned pasture (abandoned 4-10 yr) and secondary forest (abandoned 10-20 yr). Conversion and succession had obvious and significant effects on canopy cover, canopy height, species composition, and species richness; it appeared that succession of secondary forests was proceeding toward a floristic composition like that of the primary forests. Significant changes in soil properties associated with conversion of forest to pasture included: (1) a decrease in acidity and increase in some base exchange properties, (2) and increase in bulk density and a concomitant decrease in porosity, (3) higher concentrations of NH[sub 4][sup +], (4) lower concentrations of NO[sub 3][sup [minus

  5. Grazing: the whole picture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Environmental concerns for our farms include nutrient leaching to ground water, runoff in surface water, gaseous emissions, and the carbon footprint of our production systems. Recent reports have labeled grazing-based dairies as less environmentally sustainable compared to year around confinement sy...

  6. Runoff and sediment responses to grazing native and introduced species on highly erodible Southern Great Plains soil

    NASA Astrophysics Data System (ADS)

    Wine, Michael L.; Zou, Chris B.; Bradford, James A.; Gunter, Stacey A.

    2012-07-01

    SummaryOld World Bluestems, such as yellow bluestem (Bothriochloa ischaemum), have been seeded extensively in the Southern Great Plains because they are responsive to nitrogen fertilization and allow for higher stocking rates. From 1991 to 2005, we measured the effects of moderately grazing prairie species and heavily grazing fertilized yellow bluestem on runoff, sediment yield, leaf litter cover, and aboveground plant biomass for four adjacent watersheds located at the USDA-ARS Southern Plains Range Research Station in the sub-humid Rolling Red Plains of western Oklahoma. Here we show that factors other than leaf litter cover and biomass determine variation in runoff when leaf litter exceeds 70%. Runoff was related to grazing rate and storm size and inversely related to storm duration. Rainfall thresholds were similar between the moderately grazed prairie watersheds (15 mm) and the heavily grazed yellow bluestem watersheds (18 mm); however, the slope of the rainfall-runoff curve from heavily grazed yellow bluestem (0.242) was steeper than that of moderately grazed prairie (0.087). Slightly higher runoff from heavily grazed yellow bluestem relative to moderately grazed prairie may occur due to compaction of both the leaf litter and topsoil. Sediment yield was low from moderately grazed native prairie and heavily grazed yellow bluestem. Our findings indicate that both treatments assessed appear hydrologically sustainable.

  7. Forages and pastures symposium: fungal endophytes of tall fescue and perennial ryegrass: pasture friend or foe?

    PubMed

    Young, C A; Hume, D E; McCulley, R L

    2013-05-01

    Tall fescue [Lolium arundinaceum (Schreb.) Darbysh. syn. Festuca arundinacea Schreb.] and perennial ryegrass (Lolium perenne L.) are important perennial forage grasses utilized throughout the moderate- to high-rainfall temperate zones of the world. These grasses have coevolved with symbiotic fungal endophytes (Epichloë/Neotyphodium spp.) that can impart bioactive properties and environmental stress tolerance to the grass compared with endophyte-free individuals. These endophytes have proven to be very important in pastoral agriculture in the United States, New Zealand, and Australia, where forage grasses are the principal feed for grazing ruminants. In this review, we describe the biology of these grass-endophyte associations and implications for the livestock industries that are dependent on these forages. Endophyte alkaloid production is put in context with endophyte diversity, and we illustrate how this has facilitated utilization of grasses infected with different endophyte strains that reduce livestock toxicity issues. Utilization of tall fescue and use of perennial ryegrass in the United States, New Zealand, and Australia are compared, and management strategies focused predominantly on the success of endophyte-infected perennial ryegrass in New Zealand and Australia are discussed. In addition, we consider the impact of grass-endophyte associations on the sustainability of pasture ecosystems and their likely response to future changes in climate. PMID:23307839

  8. Discontinuous dynamics with grazing points

    NASA Astrophysics Data System (ADS)

    Akhmet, M. U.; Kıvılcım, A.

    2016-09-01

    Discontinuous dynamical systems with grazing solutions are discussed. The group property, continuation of solutions, continuity and smoothness of solutions are thoroughly analyzed. A variational system around a grazing solution which depends on near solutions is constructed. Orbital stability of grazing cycles is examined by linearization. Small parameter method is extended for analysis of grazing orbits, and bifurcation of cycles is observed in an example. Linearization around an equilibrium grazing point is discussed. The results can be extended on functional differential equations, partial differential equations and others. Appropriate illustrations are depicted to support the theoretical results.

  9. Milk production and economic measures in confinement or pasture systems using seasonally calved Holstein and Jersey cows.

    PubMed

    White, S L; Benson, G A; Washburn, S P; Green, J T

    2002-01-01

    This 4-yr study examined total lactation performance of dairy cows in two feeding systems: pasture-based and confinement. Spring and fall calving herds were used and each seasonal herd had 36 cows on pasture and 36 cows in confinement with 282 Holstein and 222 Jersey cows included over seven seasonal replicates. Pasture-fed cows received variable amounts of grain and baled haylage depending upon pasture availability. Confinement cows received a total mixed ration with corn silage as the primary forage. Data were collected on milk production, feed costs, and other costs. Pasture-fed cows produced 11.1% less milk than confinement cows. Across treatments, Jerseys produced 23.3% less milk than Holsteins, but calving season and various interactions were not significant. Feed costs averaged $0.95/cow per day lower for pastured cows than confinement cows. Feed costs were lower for Jerseys than Holsteins and for cows calving in spring. Income over feed costs averaged $7.05 +/- 0.34 for confinement Holsteins, $6.89 +/- 0.34 for pastured Holsteins, $5.68 +/- 0.34 for confinement Jerseys, and $5.36 +/- 0.34 for pastured Jerseys; effects of breed were significant but treatment, season, and interactions were not. Economic factors such as labor for animal care, manure handling, forage management, and cow culling rates favored pastured cows. Higher fertility and lower mastitis among Jerseys partially offsets lower income over feed cost compared with Holsteins. Milk production was lower in this study for pasture-based systems but lower feed costs, lower culling costs, and other economic factors indicate that pasture-based systems can be competitive with confinement systems.

  10. Ingestive Behavior of Heifers Supplemented with Glycerin in Substitution of Corn on Brachiaria brizantha Pasture

    PubMed Central

    Facuri, L. M. A. M.; Silva, R. R.; da Silva, F. F.; de Carvalho, G. G. P.; Sampaio, C. B.; Mendes, F. B. L.; Lisboa, M. M.; Barroso, D. S.; Carvalho, V. M.; Pereira, M. M. S.

    2014-01-01

    The objective was to evaluate the ingestive behavior of crossbred heifers finished on a Brachiaria brizantha cv. Marandu pasture receiving four levels of glycerin in their supplementation. Thirty-six crossbred heifers with average initial weight of 264.83±3.83 kg and 20 months of age were distributed into a completely randomized design with four treatments and nine replications: control (0%), 4.82%, 10.12%, and 15.56% glycerin in the dry matter. The grazing time reduced linearly (p<0.05), whereas the time spent on activities like rumination, idleness, trough and total chewing time were quadratically affected (p<0.05). Bite rate and number of bites/day were quadratically influenced (p<0.05). The number of bites/swallowed cud and the number of bites/minute, however, increased linearly (p<0.05). Although the time spent on each cud and number of chews per cud were not affected (p>0.05). The number of rumination periods reduced linearly (p<0.05), whereas the number of grazing, idle and trough periods, and the times per grazing, idle, rumination and trough periods were quadratically affected (p<0.05). The feed and rumination efficiencies of the dry matter, non-fibrous carbohydrates, pasture dry matter and concentrate were quadratically affected (p>0.05) whereas the feed efficiency of neutral detergent fiber reduced linearly (p<0.05). Addition of glycerin in substitution of corn in supplements for animals managed on pastures does not influenced feed intake, but reduces the grazing time and increases the idle time. The supplementation also improves feed and rumination efficiencies. PMID:25358318

  11. Effects of Chicory/Perennial Ryegrass Swards Compared with Perennial Ryegrass Swards on the Performance and Carcass Quality of Grazing Beef Steers

    PubMed Central

    Marley, Christina L.; Fychan, Rhun; Davies, John W.; Scollan, Nigel D.; Richardson, R. Ian; Theobald, Vince J.; Genever, Elizabeth; Forbes, Andy B.; Sanderson, Ruth

    2014-01-01

    An experiment investigated whether the inclusion of chicory (Cichorium intybus) in swards grazed by beef steers altered their performance, carcass characteristics or parasitism when compared to steers grazing perennial ryegrass (Lolium perenne). Triplicate 2-ha plots were established with a chicory/ryegrass mix or ryegrass control. Forty-eight Belgian Blue-cross steers were used in the first grazing season and a core group (n = 36) were retained for finishing in the second grazing season. The experiment comprised of a standardisation and measurement period. During standardisation, steers grazed a ryegrass/white clover pasture as one group. Animals were allocated to treatment on the basis of liveweight, body condition and faecal egg counts (FEC) determined 7 days prior to the measurement period. The measurement period ran from 25 May until 28 September 2010 and 12 April until 11 October 2011in the first and second grazing year. Steers were weighed every 14 days at pasture or 28 days during housing. In the first grazing year, faecal samples were collected for FEC and parasite cultures. At the end of the first grazing year, individual blood samples were taken to determine O. ostertagi antibody and plasma pepsinogen levels. During winter, animals were housed as one group and fed silage. In the second grazing year, steers were slaughtered when deemed to reach fat class 3. Data on steer performance showed no differences in daily live-weight gain which averaged 1.04 kg/day. The conformation, fat grade and killing out proportion of beef steers grazing chicory/ryegrass or ryegrass were not found to differ. No differences in FEC, O. ostertagi antibody or plasma pepsinogen levels of beef steers grazing either chicory/ryegrass or ryegrass were observed. Overall, there were no detrimental effects of including chicory in swards grazed by beef cattle on their performance, carcass characteristics or helminth parasitism, when compared with steers grazing ryegrass. PMID:24489708

  12. Guild structure of a riparian avifauna relative to seasonal cattle grazing

    USGS Publications Warehouse

    Knopf, F.L.; Sedgwick, J.A.; Cannon, R. W.

    1988-01-01

    Knopf et al. found that summer cattle grazing has an adverse effect on the presence of certain willow-dependent songbirds. Pastures that have historical summer grazing no longer have the Willow flycatcher, Lincoln's sparrow and the White-crowned sparrow present. Yet in these same areas, birds like the American Robin, Brown-headed cowbird and the Red-winged blackbird have increased in density. One possible answer for the decrease in some songbirds is the fact that the main focus of the Arapaho National Wildlife Refuge is on waterfowl habitat, which requires large amounts of open space (opposite of desirable songbird habitat).

  13. Effect of molasses, corn meal or a combination of molasses plus corn meal on ruminal fermentation of orchardgrass pasture in continuous culture fermenters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although molasses is being used by organic dairy farmers as a lower-cost energy alternative to corn, little research currently exists evaluating the effects of molasses as the sole supplement on ruminal fermentation of grazing dairy cows. This study evaluated the effects of pasture supplementation w...

  14. The effects of a ration change from a total mixed ration to pasture on health and production of dairy cows.

    PubMed

    Schären, M; Jostmeier, S; Ruesink, S; Hüther, L; Frahm, J; Bulang, M; Meyer, U; Rehage, J; Isselstein, J; Breves, G; Dänicke, S

    2016-02-01

    In pasture-based dairy production systems, dairy cows often receive a silage- and concentrate-based ration [total mixed ration (TMR)] during wintertime and are gradually introduced to fresh herbage in spring. The present study aimed to investigate how the transition to this new nutritional situation influenced different production and health indicators. A 10-wk trial was performed in spring 2014, including 60 dairy cows of the German Holstein breed (166±23 d in milk, 23.5±3.7 kg of milk/d; means ± SD). The cows were divided into a pasture and a confinement group (PG and CG, respectively). The CG stayed on a TMR-based diet (35% corn silage, 35% grass silage, 30% concentrate; DM basis), whereas the PG was gradually transitioned from a TMR- to a pasture-based ration (wk 1=TMR-only, wk 2=3 h/d on pasture, wk 3 and 4=12 h/d on pasture, wk 5-10=pasture-only). A continuous grazing system was implemented on a ryegrass dominated pasture and temperature humidity indices were assessed based on continuous recording of temperature and humidity indoors as well as outdoors. Dry matter intake (DMI) from TMR, milk production, body weight (BW), and body condition score decreased as soon as the PG had partial access to pasture. Milk production and BW decreased even further in the first week on a full grazing ration, but thereafter BW increased again and milk production stabilized. The DMI estimation using the n-alkane method in wk 7 and 9 revealed an increase in DMI from pasture between the 2 time points and indicates an adaptation of grazing behavior and metabolism over several weeks. Increased serum β-hydroxybutyrate and fatty acids concentrations at several time points, as well as a continuous body condition score decrease during the whole course of the trial, indicate an energy deficit in the PG. A significant correlation between serum glucose concentrations and the temperature humidity indices was observed. An increase in serum and milk urea concentrations as well as an

  15. Capturing urine while maintaining pasture intake, milk production, and animal welfare of dairy cows in early and late lactation.

    PubMed

    Clark, C E F; McLeod, K L M; Glassey, C B; Gregorini, P; Costall, D A; Betteridge, K; Jago, J G

    2010-05-01

    Capturing urine and spreading it evenly across a paddock reduces the risk of nitrogen loss to the environment. This study investigated the effect of 16h/d removal from pasture on the capture of urination events, milk production, pasture intake, and animal welfare from cows grazing fresh pasture in early and late lactation. Forty-eight Holstein-Friesian cows in early [470+/-47kg of body weight (BW); 35+/-9 days in milk] and late (498+/-43kg of BW; 225+/-23 days in milk) lactation were allocated to 3 treatment groups. Cows had access to pasture for either 4h after each milking (2 x 4), for 8h between morning and afternoon milkings (1 x 8), or for 24h, excluding milking times (control). When not grazing, the 2 x 4 and 1 x 8 groups were confined to a plastic-lined loafing area with a woodchip surface. In early lactation, the proportion of urinations on pasture and laneways was reduced from 89% (control) to 51% (1 x 8) and 54% (2 x 4) of total urinations. The 1 x 8 cows ate less pasture [10.9kg of dry matter (DM)/cow per day] than the control (13.6kg of DM/cow per day) and 2 x 4 (13.0kg of DM/cow per day) cows, which did not differ from each other. The 1 x 8 and 2 x 4 cows produced less milk (21 and 22kg of milk/cow per day, respectively) compared with control cows (24kg of milk/cow per day). There were no differences in BW or body condition score (BCS) change across treatment groups, with all groups gaining BW and BCS during the experimental period. In late lactation, there was no difference in pasture intake (mean=8.8kg of DM/cow per day), milk production (mean=10kg of milk/cow per day), and BW or BCS change (mean=3.7kg and -0.2U/cow per week, respectively) between treatment groups. As in early lactation, urinations on pasture and laneways were reduced from 85% (control) to 56% (1 x 8) and 50% (2 x 4) of total urinations. These findings highlight an opportunity to maintain performance and welfare of grazing cows in early and late lactation while capturing additional

  16. Effects of pasture renovation on hydrology, nutrient runoff, and forage yield.

    PubMed

    de Koff, J P; Moore, P A; Formica, J; Van Eps, M; DeLaune, P B

    2011-01-01

    Proper pasture management is important in promoting optimal forage growth and reducing runoff and nutrient loss. Pasture renovation is a management tool that improves aeration by mechanically creating holes or pockets within the soil. Pasture renovation was performed before manure application (poultry litter or swine slurry) on different pasture soils and rainfall simulations were conducted to identify the effects of pasture renovation on nutrient runoff and forage growth. Renovation of small plots resulted in significant and beneficial hydrological changes. During the first rainfall simulation, runoff volumes were 45 to 74% lower for seven out of eight renovated treatments, and infiltration rates increased by 3 to 87% for all renovated treatments as compared with nonrenovated treatments. Renovation of pasture soils fertilized with poultry litter led to significant reductions in dissolved reactive P (DRP) (74-87%), total P (TP) (76-85%), and total nitrogen (TN) (72-80%) loads in two of the three soils studied during the first rainfall simulation. Renovation did not result in any significant differences in forage yields. Overall, beneficial impacts of renovation lasted up to 3 mo, the most critical period for nutrient runoff following manure application. Therefore, renovation could be an important best management practice in these areas.

  17. Greenhouse Gas Emissions from Pasture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Carbon dioxide, nitrous oxide, and methane are the primary greenhouse gases associated with global climate change. Livestock production’s contribution to carbon dioxide emissions is minimal, but it is a substantial contributor to both nitrous oxide and methane emissions. In both grazing and confin...

  18. Influence of elk grazing on soil properties in Rocky Mountain National Park

    USGS Publications Warehouse

    Binkley, D.; Singer, F.; Kaye, M.; Rochelle, R.

    2003-01-01

    We used three 35-year exclosures to examine the effects of high elk populations on a variety of soil properties in three vegetation types: upland sagebrush, aspen, and meadow. Grazing and hoof action by elk significantly increased bulk density (from 0.87 kg/l ungrazed to 0.94 kg/l grazed), with greater effects on soils with fewer rocks. Grazing substantially reduced extractable calcium, magnesium, potassium and phosphorus in the sagebrush type, but not in the aspen or meadow types. The only grazing effect on pH came in aspen types, where grazing prevented aspen establishment, and kept soil pH about 0.7 units higher than under aspen inside the exclosures. Grazing had no overall effect on total soil C and N across all exclosures and vegetation types. The availability of soil nitrogen, indexed by in-field resin bags and net mineralization in soil cores, showed little overall effect of grazing. Limited data on soil leaching indicated a possibility of strong increases in nitrate leaching with grazing for an aspen vegetation type at one exclosure. Although we found little effect of grazing on soil N supply, we note that N fertilization doubled the production of grasses and shrubs; if grazing eventually led to changes in soil N supply, species composition and growth would likely change. ?? 2003 Elsevier B.V. All rights reserved.

  19. Factors associated with the financial performance of spring-calving, pasture-based dairy farms.

    PubMed

    Ramsbottom, G; Horan, B; Berry, D P; Roche, J R

    2015-05-01

    As land becomes a limiting resource for pasture-based dairy farming, the inclusion of purchased supplementary feeds to increase milk production per cow (through greater dry matter intake) and per hectare (through increased stocking rate) is often proposed as a strategy to increase profitability. Although a plausible proposition, virtually no analysis has been done on the effect of such intensification on the profitability of commercial pasture-based dairy farm businesses. The objective of this study was to characterize the average physical and financial performance of dairy systems differing in the proportion of the cow's diet coming from grazed pasture versus purchased supplementary feeds over 4 yr, while accounting for any interaction with geographic region. Physical, genetic, and financial performance data from 1,561 seasonal-calving, pasture-based dairy farms in Ireland were available between the years 2008 and 2011; data from some herds were available for more than 1 yr of the 4-yr study period, providing data from 2,759 dairy farm-years. The data set was divided into geographic regions, based on latitude, rainfall, and soil characteristics that relate to drainage; these factors influence the length of the pasture growth season and the timing of turnout to pasture in spring and rehousing in autumn. Farms were also categorized by the quantity of feed purchased; farms in which cows received <10, 11-20, 21-30, or >30% of their annual feed requirements from purchased feed were considered to be categories representative of increasing levels of system intensification. Geographic region was associated with differences in grazing days, pasture harvested per hectare, milk production per cow and per hectare, and farm profitability. Farms in regions with longer grazing seasons harvested a greater amount of pasture [an additional 19kg of dry matter (DM)/ha per grazing day per hectare], and greater pasture harvested was associated with increased milk component yield per

  20. Ammonia emissions from urea application to permanent pasture on a volcanic soil

    NASA Astrophysics Data System (ADS)

    Salazar, F.; Martínez-Lagos, J.; Alfaro, M.; Misselbrook, T.

    2012-12-01

    Agriculture is the largest source of ammonia (NH3) emission to the atmosphere, deriving mainly from livestock urine and manures, but fertilizer applications to pastures and crops also represent an important source. In Chile, where agriculture and cattle production are important activities (accounting for 4.5% of GDP along with the forestry sector), there are very few published data regarding NH3 emissions from pasture and crop fertilization. This study aimed to provide the first empirical field data for Chile on N losses due to NH3 volatilization following urea application to permanent pasture on a volcanic soil and to assess the influence of environmental conditions on emissions. Four field experiments were carried out on a volcanic acid soil using the micrometeorological integrated horizontal flux (IHF) mass balance method. Measurements were made in winter 2005 and 2007, and spring 2007 and 2008 following urea N fertilization to a permanent pasture at a rate equivalent to 100 kg N ha-1. Cumulative NH3 emissions over the measurement period were 1.4 and 7.7 kg N ha-1 for winter applications, and 12.2 and 26.7 kg N ha-1 for spring dressings. These N losses due to NH3 volatilization are within the range of emissions reported elsewhere. Consideration of urea application timing in Chile, with regards to weather and soil conditions, could have important consequences on minimising potential N losses via volatilization with associated financial benefits to farmers.

  1. Fall-grown oat to extend the fall grazing season for replacement dairy heifers.

    PubMed

    Coblentz, W K; Brink, G E; Hoffman, P C; Esser, N M; Bertram, M G

    2014-03-01

    Our objective was to assess the pasture productivity and forage characteristics of 2 fall-grown oat (Avena sativa L.) cultivars, specifically for extending the grazing season and reducing reliance on harvested forages by replacement dairy heifers. A total of 160 gravid Holstein heifers (80 heifers/yr) were stratified by weight, and assigned to 1 of 10 identical research pens (8 heifers/pen). Initial body weights were 480 ± 43.5 kg in 2011 and 509 ± 39.4 kg in 2012. During both years of the trial, four 1.0-ha pasture replicates were seeded in August with Ogle oat (Schumitsch Seed Inc., Antigo, WI), and 4 separate, but similarly configured, pasture replicates were seeded with Forage Plus oat (Kratz Farms, Slinger, WI). Heifer groups were maintained as units, assigned to specific pastures, and then allowed to graze fall-oat pastures for 6h daily before returning to the barn, where they were offered a forage-based basal total mixed ration. Two heifer groups were retained in confinement (without grazing) as controls and offered the identical total mixed ration as pasture groups. During 2011, available forage mass increased with strong linear and quadratic effects for both cultivars, peaking at almost 9 Mg/ha on October 31. In contrast, forage mass was not affected by evaluation date in 2012, remaining ≤ 2,639 kg/ha across all dates because of droughty climatic conditions. During 2012, Ogle exhibited greater forage mass than Forage Plus across all sampling dates (2,678 vs. 1,856 kg/ha), largely because of its more rapid maturation rate and greater canopy height. Estimates of energy density for oat forage ranged from 59.6 to 69.1% during 2011, and ranged narrowly from 68.4 to 70.4% during 2012. For 2011, responses for both cultivars had strong quadratic character, in which the most energy-dense forages occurred in mid November, largely due to accumulation of water-soluble carbohydrates that reached maximum concentrations of 18.2 and 15.1% for Forage Plus and Ogle

  2. Fall-grown oat to extend the fall grazing season for replacement dairy heifers.

    PubMed

    Coblentz, W K; Brink, G E; Hoffman, P C; Esser, N M; Bertram, M G

    2014-03-01

    Our objective was to assess the pasture productivity and forage characteristics of 2 fall-grown oat (Avena sativa L.) cultivars, specifically for extending the grazing season and reducing reliance on harvested forages by replacement dairy heifers. A total of 160 gravid Holstein heifers (80 heifers/yr) were stratified by weight, and assigned to 1 of 10 identical research pens (8 heifers/pen). Initial body weights were 480 ± 43.5 kg in 2011 and 509 ± 39.4 kg in 2012. During both years of the trial, four 1.0-ha pasture replicates were seeded in August with Ogle oat (Schumitsch Seed Inc., Antigo, WI), and 4 separate, but similarly configured, pasture replicates were seeded with Forage Plus oat (Kratz Farms, Slinger, WI). Heifer groups were maintained as units, assigned to specific pastures, and then allowed to graze fall-oat pastures for 6h daily before returning to the barn, where they were offered a forage-based basal total mixed ration. Two heifer groups were retained in confinement (without grazing) as controls and offered the identical total mixed ration as pasture groups. During 2011, available forage mass increased with strong linear and quadratic effects for both cultivars, peaking at almost 9 Mg/ha on October 31. In contrast, forage mass was not affected by evaluation date in 2012, remaining ≤ 2,639 kg/ha across all dates because of droughty climatic conditions. During 2012, Ogle exhibited greater forage mass than Forage Plus across all sampling dates (2,678 vs. 1,856 kg/ha), largely because of its more rapid maturation rate and greater canopy height. Estimates of energy density for oat forage ranged from 59.6 to 69.1% during 2011, and ranged narrowly from 68.4 to 70.4% during 2012. For 2011, responses for both cultivars had strong quadratic character, in which the most energy-dense forages occurred in mid November, largely due to accumulation of water-soluble carbohydrates that reached maximum concentrations of 18.2 and 15.1% for Forage Plus and Ogle

  3. [Phytomass utilization and deposition of feces by ungulates on steppe pastures of eastern Mongolia].

    PubMed

    Abaturov, B D; Dmitriev, I A; Jargalsaikhan, L; Omarov, K Z

    2008-01-01

    The amount of phytomass removed by a complex of livestock (horses, cattle, sheep, and goats) and wild ungulates (Mongolian gazelle Procapra gutturosa Pall.) grazing in plain and mountain pastures of eastern Mongolia has been estimated by taking account of feces deposited by these animals. The results show that at an animal density of up to 30 head/km2, the total annual amount of feces reaches 140 kg/ha (dry weight), with the greater part (up to 90 kg/ha) being deposited by horses. The contribution of Mongolian gazelles in some pastures reaches 20-40 kg/ha per year. Decomposition of feces proceeds very slowly, with the annual loss of their weight averaging only 9-12%. This is evidence for gradual accumulation of nondecomposed matter in the soil. The removal of phytomass by the complex of ungulates, calculated from the amount of feces with regard to their annual loss and forage digestibility, varies in different grazing areas from 240 to 400 kg/ha (25-60% of the total aboveground phytomass). The greatest amount of phytomass is utilized by horses, reaching 200 kg/ha (13%), and Mongolian gazelles utilize up to 86 kg/ha per year. In the growing season, ungulates remove no more than 11-16% of the total aboveground phytomass. It is concluded that the impact of total ungulate stock does not impair the productivity of vegetation in the pastures studied. PMID:18663973

  4. Natural Wetlands Mediate Non-point Source Water Pollution From Irrigated Pastures

    NASA Astrophysics Data System (ADS)

    Knox, K.; Dahlgren, R. A.; Tate, K. W.

    2005-12-01

    Non-point source discharge from grazed pastures may be high in nutrients, sediment, and pathogens, three major contributors to water quality impairment in California. Intercepting pollution at its source and managing water quality within the landscape are essential to maintaining healthy downstream waters. We investigated the efficacy of flow-through wetlands interspersed throughout the agricultural landscape to reduce non-point source pollution of tailwater from cattle-grazed, irrigated pastures in the Sierra Nevada Foothills of California. Wetlands are known to positively impact water quality through ecological processes such as filtration, sedimentation, microbial transformations and plant uptake of nutrients. Influent and effluent water of small (0.25 ha), natural wetlands located downstream from flood irrigated pastures was analyzed for Escherichia coli, NO3-N, total N, total suspended solids (TSS), total P, and dissolved organic carbon (DOC) throughout two summer irrigation seasons (June to October). We compared reductions of sediment, nutrients and E. coli provided by a healthy, non-degraded wetland with reductions from flow through a channelized, degraded wetland. Large reductions in E. coli (>75%) and TSS (>50%) were observed in water exiting the healthy wetland while nutrient and DOC (~ 20%) concentrations were less affected by flow through the wetland. The channelized wetland provided smaller reductions in all constituents than did the non-degraded wetland. Results from this study demonstrate that small flow-through wetlands can improve water quality through the attenuation of E. coli and suspended sediments, and to a lesser degree DOC and nutrients.

  5. Fluoride accumulation in pasture forages and soils following long-term applications of phosphorus fertilisers.

    PubMed

    Loganathan, P; Hedley, M J; Wallace, G C; Roberts, A H

    2001-01-01

    Ingestion of soils with high fluoride (F) concentration may cause chronic fluorosis in grazing animals. Analysis of New Zealand pasture soils with long-term phosphorus (P) fertilisation histories showed that total surface soil (0-75 mm depth) F concentration increased up to 217-454 mg kg-1 with P fertiliser application. One-third to two-thirds of F applied in fertilisers resides in the top 75 mm soil depth. Pasture forage accumulation of F was low, and therefore, F intake by grazing animals through pasture consumption is expected to be much lower than F intake by soil ingestion. Ten annual applications of single superphosphate (30 and 60 kg P ha-1 year-1) to a Pallic Soil (Aeric Fragiaqualf) significantly increased total F and labile F (0.01 M CaCl2 extract) concentrations to 200 and 120 mm depths, respectively, of the 300 mm depth investigated. The mobility of F in the soil profile was similar to two other elements, P and cadmium derived from the fertiliser.

  6. Impacts of cattle grazing on spatio-temporal variability of soil moisture and above-ground live plant biomass in mixed grasslands

    NASA Astrophysics Data System (ADS)

    Virk, Ravinder

    Areas with relatively high spatial heterogeneity generally have more biodiversity than spatially homogeneous areas due to increased potential habitat. Management practices such as controlled grazing also affect the biodiversity in grasslands, but the nature of this impact is not well understood. Therefore this thesis studies the impacts of variation in grazing on soil moisture and biomass heterogeneity. These are not only important in terms of management of protected grasslands, but also for designing an effective grazing system from a livestock management point of view. This research is a part of the cattle grazing experiment underway in Grasslands National Park (GNP) of Canada since 2006, as part of the adaptive management process for restoring ecological integrity of the northern mixed-grass prairie region. An experimental approach using field measurements and remote sensing (Landsat) was combined with modelling (CENTURY) to examine and predict the impacts of grazing intensity on the spatial heterogeneity and patterns of above-ground live plant biomass (ALB) in experimental pastures in a mixed grassland ecosystem. The field-based research quantified the temporal patterns and spatial variability in both soil moisture (SM) and ALB, and the influence of local intra-seasonal weather variability and slope location on the spatio-temporal variability of SM and ALB at field plot scales. Significant impacts of intra-seasonal weather variability, slope position and grazing pressure on SM and ALB across a range of scales (plot and local (within pasture)) were found. Grazing intensity significantly affected the ALB even after controlling for the effect of slope position. Satellite-based analysis extended the scale of interest to full pastures and the surrounding region to assess the effects of grazing intensity on the spatio-temporal pattern of ALB in mixed grasslands. Overall, low to moderate grazing intensity showed increase in ALB heterogeneity whereas no change in ALB

  7. Quantifying vegetation response to grazing intensity and precipitation on Chihuahuan Desert Rangeland using remote sensing and GIS

    NASA Astrophysics Data System (ADS)

    Mohamed, Ahmed H.

    High spatial resolution satellite imagery is a promising data source for studying vegetation dynamics. The overall goal for this study was to use QuickBird high spatial resolution satellite imagery to develop methods for vegetation analysis and tracking livestock distribution. I hypothesized that using these technologies would create appropriate new management tool that provides spatial, temporal, and current information for extensive rangeland pastures. This research was conducted on four large scale pastures at the Chihuahuan Desert Rangeland Research Center (CDRRC) in south central New Mexico. Two QuickBird ortho-ready standard satellite images (DigitalGlobe Inc., Longmont, Colorado, USA) were acquired for the study area in May of 2006 and 2009. The image covered an area of 4381 ha and had a 60 cm panchromatic resolution and 2.4 m multispectral resolution. A 4-band pan-sharpened image with spatial resolution of 60 cm was produced for each QuickBird image. Per-pixel spectral based classification algorithms were used to classify the two images and map the primary vegetation types in the study area. Post-classification change detection was conducted between the May 2006 image and the May 2009 image. GPS collars were used to track 2 cows in each pasture for 10 weeks during the winter of 2010. Forage production for the primary perennial grasses was estimated from 40 permanent vegetation plots across the study area in May 2009. Spectral-based classification techniques were very effective in classifying QuickBird satellite imagery. Overall accuracy of the classified map ranged from 89 to 95 %. Increasing honey mesquite (Prosopis glandulosa Torr.) canopy cover corresponded to lower perennial grass forage production. Improvement in range condition in terms of declining shrub cover and bare ground and increased grass-mix vegetation was noted in conservatively grazed (35% utilization) pastures. However, only slight changes were observed in lightly grazed pastures. Grazing

  8. Dental pathology in conventionally fed and pasture managed dairy cattle.

    PubMed

    Fadden, A N; Poulsen, K P; Vanegas, J; Mecham, J; Bildfell, R; Stieger-Vanegas, S M

    2016-01-01

    Healthy teeth are important in the first stages of digestion for dairy cattle, yet little is known about bovine dental disease. This study aimed to investigate dental pathology of dairy cattle in two parts. First dairy cattle cadaver heads (n=11) were examined at the time of culling. Second, the authors performed oral exams in cattle fed a total mixed ration (TMR) (n=200) and pasture-based (n=71) grazing cattle. Cadaver heads were imaged using radiography and computed tomography before gross dissection to study dental anatomy and pathology. The most prevalent dental abnormalities were excessive transverse ridging of the occlusal surface, the presence of diastemas and third molar dental overgrowths (M3DO) in cadaver heads. Average thickness of subocclusal dentine ranged from 3.5 mm to 5.8 mm in cheek teeth but was >10 mm in maxillary teeth with M3DO. Radiographic findings were compared with oral examinations in live cattle. Prevalence of M3DO upon oral examination was 19 per cent and 28 per cent in herds of cattle fed a TMR diet and 0 per cent in a herd of grazing cattle. Dental abnormalities are prevalent in dairy cattle but due to thin subocclusal dentine in the cheek teeth, established equine dental treatment methodology is not appropriate for bovine cheek teeth with the exception of those that have developed M3DO.

  9. An outbreak of Vicia villosa (hairy vetch) poisoning in grazing Aberdeen Angus bulls in Argentina.

    PubMed

    Odriozola, E; Paloma, E; Lopez, T; Campero, C

    1991-06-01

    Vicia villosa (hairy vetch) is used as a forage source in some cattle-producing areas in Argentina. The plant had no previous reports of toxicity in this country. A herd of 33 Aberdeen Angus bulls grazed during 20 days in October on a pasture composed mainly of hairy vetch. Eight animals developed conjunctivitis, rinitis, dermatitis, loss of hair and fever. All of them died within 15 d after the development of signs with a marked loss of body condition. No more animals became sick 5 d after the removal of the herd from the pasture. Serum parameters tested (calcium, phosphorus, magnesium, GOT, alfa-GT and bilirubin) enlarged liver and spleen, generalized hemorrhage in the abomasum, dilated kidneys and multiple pale areas on the heart. Severe necrotizing granulomatous myocarditis, interstitial nephritis, and necrotizing cholangitis were the most striking microscopic changes. Close observation of animals feeding on pastures in which V villosa is dominant is the only prevention. PMID:1858312

  10. Influence of Restricted Grazing Time Systems on Productive Performance and Fatty Acid Composition of Longissimus dorsi in Growing Lambs

    PubMed Central

    Wang, Zhenzhen; Chen, Yong; Luo, Hailing; Liu, Xueliang; Liu, Kun

    2015-01-01

    Fifty 3-month-old male Tan lambs (similar in body weight) were divided into 5 groups to investigate the effects of different restricted pasture grazing times and indoor supplementation on the productive performances and fatty acid composition of the intramuscular fat in growing lambs. The lambs grazed for different periods of time (12 h/d, 8 h/d, 4 h/d, 2 h/d, and 0 h) and received various amounts of supplementary feedings during the 120-day trial. Pasture dry matter intake (DMI), total DMI, average daily gains and the live body weights of the lambs were measured during the experiment. The animals were slaughtered at the end of the study, their carcass traits were measured, and their longissimus dorsi muscles were sampled to analyze the intramuscular fat (IMF) content and fatty acid profiles. The results indicated that the different durations of grazing and supplementary feedings affected the animal performances and the composition of fatty acids. Grazing for 8 h/d or 2 h/d with the corresponding supplementary concentrate resulted in lambs with higher body weights, carcass weights and IMF contents. Lambs with longer grazing times and less concentrate accumulated more healthy fatty acids such as conjugated linoleic acid and n-3 polyunsaturated fatty acid and had higher n-3/n-6 ratios. Overall, a grazing allowance of 8 h/d and the corresponding concentrate was recommended to maintain a high quantity and quality of lamb meat. PMID:26104518

  11. Pasture BMP effectiveness using an HRU-based subarea approach in SWAT.

    PubMed

    Sheshukov, Aleksey Y; Douglas-Mankin, Kyle R; Sinnathamby, Sumathy; Daggupati, Prasad

    2016-01-15

    Many conservation programs have been established to motivate producers to adopt best management practices (BMP) to minimize pasture runoff and nutrient loads, but a process is needed to assess BMP effectiveness to help target implementation efforts. A study was conducted to develop and demonstrate a method to evaluate water-quality impacts and the effectiveness of two widely used BMPs on a livestock pasture: off-stream watering site and stream fencing. The Soil and Water Assessment Tool (SWAT) model was built for the Pottawatomie Creek Watershed in eastern Kansas, independently calibrated at the watershed outlet for streamflow and at a pasture site for nutrients and sediment runoff, and also employed to simulate pollutant loads in a synthetic pasture. The pasture was divided into several subareas including stream, riparian zone, and two grazing zones. Five scenarios applied to both a synthetic pasture and a whole watershed were simulated to assess various combinations of widely used pasture BMPs: (1) baseline conditions with an open stream access, (2) an off-stream watering site installed in individual subareas in the pasture, and (3) stream or riparian zone fencing with an off-stream watering site. Results indicated that pollutant loads increase with increasing stocking rates whereas off-stream watering site and/or stream fencing reduce time cattle spend in the stream and nutrient loads. These two BMPs lowered organic P and N loads by more than 59% and nitrate loads by 19%, but TSS and sediment-attached P loads remained practically unchanged. An effectiveness index (EI) quantified impacts from the various combinations of off-stream watering sites and fencing in all scenarios. Stream bank contribution to pollutant loads was not accounted in the methodology due to limitations of the SWAT model, but can be incorporated in the approach if an amount of bank soil loss is known for various stocking rates. The proposed methodology provides an adaptable framework for

  12. 25 CFR 700.711 - Grazing permits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... OFFICE OF NAVAJO AND HOPI INDIAN RELOCATION COMMISSION OPERATIONS AND RELOCATION PROCEDURES New Lands Grazing § 700.711 Grazing permits. (a) All livestock grazed on the New Lands must be covered by a grazing... residency on the New Lands Range Unit of permit issue, and (4) Own livestock which graze on the range...

  13. Carbon fluxes of Kobresia pygmaea pastures on the Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Foken, T.; Biermann, T.; Babel, W.; Ma, Y.

    2013-12-01

    With an approximate cover of 450,000 km2 on the Tibetan Plateau (TP), the Cyperaceae Kobresia pygmaea forms he world's largest alpine ecosystem. This species, especially adapted to grazing pressure, grows to a height of only 2-6 cm and can be found in an altitudinal range of 4000 to 5960 m a.s.l. A special characteristic of this ecosystem is the stable turf layer, which is built up from roots and plays a significant role in protecting soil from erosion. This is of great importance since soils on the TP store 2.5 % of the global soil organic carbon stocks. The aim of the investigation was the study of the carbon storage and the impact of human-induced land use change on these Kobresia pygmaea pastures. We therefore applied eddy-covariance measurements and modelling as a long-term control of the fluxes between the atmosphere and the pastures and 13C labelling for the investigation of flux partitioning, and chamber measurements to investigate the degradation of the pastures. Combining CO2 budgets observed in 2010 with eddy-covariance measurements and relative partitioning of Carbon fluxes estimated with 13C labelling enabled us to characterise the C turnover for the vegetation period with absolute fluxes within the plant-soil-atmosphere continuum. These results revealed that this ecosystem indeed stores a great amount of C in below-ground pools, especially in the root turf layer. To further investigate the importance of the root layer, the experiments in 2012 focused on flux measurements over the different surface types which make up the heterogeneity of the Kobresia pygmaea pastures and might result from degradation due to extensive grazing. The three surface types investigated with a LiCOR long-term monitoring chamber system include Kobresia pygmaea with intact turf layer (IRM), a surface type where the turf layer is still present but the vegetation is sparse and mainly consists of Cryptogam crusts (DRM) and finally areas without the turf layer (BS). According to

  14. Subsurface application of poultry litter in pasture and no-till soils.

    PubMed

    Pote, D H; Way, T R; Kleinman, P J A; Moore, P A; Meisinger, J J; Sistani, K R; Saporito, L S; Allen, A L; Feyereisen, G W

    2011-01-01

    Poultry litter provides a rich nutrient source for crops, but the usual practice of surface-applying litter can degrade water quality by allowing nutrients to be transported from fields in surface runoff while much of the ammonia (NH3)-N escapes into the atmosphere. Our goal was to improve on conventional titter application methods to decrease associated nutrient losses to air and water while increasing soil productivity. We developed and tested a knifing technique to directly apply dry poultry litter beneath the surface of pastures. Results showed that subsurface litter application decreased NH3-N volatilization and nutrient losses in runoff more than 90% (compared with surface-applied litter) to levels statistically as low as those from control (no litter) plots. Given this success, two advanced tractor-drawn prototypes were developed to subsurface apply poultry litter in field research. The two prototypes have been tested in pasture and no-till experiments and are both effective in improving nutrient-use efficiency compared with surface-applied litter, increasing crop yields (possibly by retaining more nitrogen in the soil), and decreasing nutrient losses, often to near background (control plot) levels. A paired-watershed study showed that cumulative phosphorus losses in runoff from continuously grazed perennial pastures were decreased by 55% over a 3-yr period if the annual poultry litter applications were subsurface applied rather than surface broadcast. Results highlight opportunities and challenges for commercial adoption of subsurface poultry litter application in pasture and no-till systems. PMID:21520747

  15. Adaptive grazing management experiment: The new frontier of grazing management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Adaptive Grazing Management experiment at the USDA-ARS Central Plains Experimental Range addresses important gaps in our current understanding of grazing management including: 1) lack of management-science partnerships to more fully understand the effect of management decisions, 2) need for mana...

  16. Grazing management options in meeting objectives of grazing experiments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Decisions on which grazing management option to use in grazing experiments can be critical in meeting research objectives and generating information for the scientific community or technologies that meets the needs of forage-based enterprises. It is necessary to have an understanding of animal per...

  17. Methane emissions of beef cattle on forages: efficiency of grazing management systems.

    PubMed

    DeRamus, H Alan; Clement, Terry C; Giampola, Dean D; Dickison, Peter C

    2003-01-01

    Fermentation in the rumen of cattle produces methane (CH4). Methane may play a role in global warming scenarios. The linking of grazing management strategies to more efficient beef production while reducing the CH4 emitted by beef cattle is important. The sulfur hexafluoride (SF6) tracer technique was used to determine the effects of best management practices (BMP) grazing compared with continuous grazing on CH4 production in several Louisiana forages during 1996-1998. Cows and heifers (Bos taurus) grazed common bermudagrass [Cynodon dactylon (L.) Pers.], bahiagrass (Paspalum notatum Flugge), and ryegrass (Lolium multiflorum Lam.) pastures and were wintered on bahiagrass hay with supplements of protein molasses blocks (PMB), cottonseed meal and corn (CSMC), urea and corn (URC), or limited ryegrass grazing (LRG). Daily CH4 emissions were between 89 and 180 g d(-1) for young growing heifers and 165 to 294 g d(-1) for mature Simbrah cows. Heifers on "ad lib" ryegrass in March and April produced only one-tenth the CH4 per kg of gain as heifers on LRG of 1 h. Using BMP significantly reduced the emission of CH4 per unit of animal weight gain. Management-intensive grazing (MIG) is a BMP that offers the potential for more efficient utilization of grazed forage crops via controlled rotational grazing and more efficient conversion of forage into meat and milk. Projected CH4 annual emissions in cows reflect a 22% reduction from BMP when compared with continuous grazing in this study. With the BMP application of MIG, less methane was produced per kilogram of beef gain.

  18. Methane emissions of beef cattle on forages: efficiency of grazing management systems.

    PubMed

    DeRamus, H Alan; Clement, Terry C; Giampola, Dean D; Dickison, Peter C

    2003-01-01

    Fermentation in the rumen of cattle produces methane (CH4). Methane may play a role in global warming scenarios. The linking of grazing management strategies to more efficient beef production while reducing the CH4 emitted by beef cattle is important. The sulfur hexafluoride (SF6) tracer technique was used to determine the effects of best management practices (BMP) grazing compared with continuous grazing on CH4 production in several Louisiana forages during 1996-1998. Cows and heifers (Bos taurus) grazed common bermudagrass [Cynodon dactylon (L.) Pers.], bahiagrass (Paspalum notatum Flugge), and ryegrass (Lolium multiflorum Lam.) pastures and were wintered on bahiagrass hay with supplements of protein molasses blocks (PMB), cottonseed meal and corn (CSMC), urea and corn (URC), or limited ryegrass grazing (LRG). Daily CH4 emissions were between 89 and 180 g d(-1) for young growing heifers and 165 to 294 g d(-1) for mature Simbrah cows. Heifers on "ad lib" ryegrass in March and April produced only one-tenth the CH4 per kg of gain as heifers on LRG of 1 h. Using BMP significantly reduced the emission of CH4 per unit of animal weight gain. Management-intensive grazing (MIG) is a BMP that offers the potential for more efficient utilization of grazed forage crops via controlled rotational grazing and more efficient conversion of forage into meat and milk. Projected CH4 annual emissions in cows reflect a 22% reduction from BMP when compared with continuous grazing in this study. With the BMP application of MIG, less methane was produced per kilogram of beef gain. PMID:12549566

  19. Simulating rotational grazing management.

    PubMed

    Cros, M J; Duru, M; Garcia, F; Martin-Clouaire, R

    2001-09-01

    Dairy systems predominantly based on rotational grazing are notoriously hard to manage. In order to ensure profitability, this type of production requires quite good organisation, planning, and operating capability on the part of the farmer. A simulation-based decision support system, called SEPATOU, has been developed for this purpose. At the core of the decision support approach lies an explicit and rigorous modelling of the management strategy that underlies a dairy farmer's decision-making behaviour (real or hypothetical). The SEPATOU system is a discrete-event simulator that reproduces the day-to-day dynamics of the farmer's decision process and the response of the controlled biophysical system for which models of grass growth, animal consumption, and milk production are used. SEPATOU provides the means to evaluate and compare tentative strategies by simulating their application throughout the production season under different hypothetical weather conditions. The relative worth of a strategy can be assessed by analysing the effects on the biophysical system and their variability across the representative range of possible conditions that is considered. The activities to be managed concern the type and amount of conserved feed, where to fertilise and how much, the choice of fields to harvest, and most importantly, which field to graze next. Typically, SEPATOU is designed to be used by extension services and farming system scientists. It is implemented in C++ and is currently undergoing a validation process with the intended users. PMID:11697661

  20. Carbon sequestration in grasslands: grazing versus fire under climate change

    NASA Astrophysics Data System (ADS)

    Bachelet, D. M.; Kelly, R.; Parton, W. J.

    2009-12-01

    We simulated different levels of grazing and frequencies of fire using the biogeochemical model DAYCENT across a climate gradient from Montana to New Mexico to look at their long-term implications on carbon sequestration in grasslands. We also used 3 future climate scenarios and 2 CO2 emission levels to estimate interactions between disturbance and climate. In all cases, total ecosystem carbon was driven by grazing pressure with carbon stocks declining by 15-35% under moderate to heavy grazing. Fire frequency had no effect on carbon levels when 50% of the aboveground biomass was consumed by grazers and has the most impact when no grazing occurred. Warmer drier climate scenarios increased the stress to growth and caused declines in carbon stocks unless a CO2 fertilization effect increased the water use efficiency. Again, under future climate change scenario, grazing had a greater impact than fire frequency in defining the overall levels of total ecosystem carbon. Potential woody plant invasion of grasslands would alter the role of disturbance on carbon sequestration potential since frequent fires would remove shrubs from the landscape reducing the potential for increased aboveground carbon stocks with lower palatability to grazers than grasses.

  1. Pasture-feeding of Charolais steers influences skeletal muscle metabolism and gene expression.

    PubMed

    Cassar-Malek, I; Jurie, C; Bernard, C; Barnola, I; Micol, D; Hocquette, J-F

    2009-10-01

    Extensive beef production systems on pasture are promoted to improve animal welfare and beef quality. This study aimed to compare the influence on muscle characteristics of two management approaches representative of intensive and extensive production systems. One group of 6 Charolais steers was fed maize-silage indoors and another group of 6 Charolais steers grazed on pasture. Activities of enzymes representative of glycolytic and oxidative (Isocitrate dehydrogenase [ICDH], citrate synthase [CS], hydroxyacyl-CoA dehydrogenase [HAD]) muscle metabolism were assessed in Rectus abdominis (RA) and Semitendinosus (ST) muscles. Activities of oxidative enzymes ICDH, CS and HAD were higher in muscles from grazing animals demonstrating a plasticity of muscle metabolism according to the production and feeding system. Gene expression profiling in RA and ST muscles was performed on both production groups using a multi-tissue bovine cDNA repertoire. Variance analysis showed an effect of the muscle type and of the production system on gene expression (P<0.001). A list of the 212 most variable genes according to the production system was established, of which 149 genes corresponded to identified genes. They were classified according to their gene function annotation mainly in the "protein metabolism and modification", "signal transduction", "cell cycle", "developmental processes" and "muscle contraction" biological processes. Selenoprotein W was found to be underexpressed in pasture-fed animals and could be proposed as a putative gene marker of the grass-based system. In conclusion, enzyme-specific adaptations and gene expression modifications were observed in response to the production system and some of them could be candidates for grazing or grass-feeding traceability. PMID:19996487

  2. Pasture-feeding of Charolais steers influences skeletal muscle metabolism and gene expression.

    PubMed

    Cassar-Malek, I; Jurie, C; Bernard, C; Barnola, I; Micol, D; Hocquette, J-F

    2009-10-01

    Extensive beef production systems on pasture are promoted to improve animal welfare and beef quality. This study aimed to compare the influence on muscle characteristics of two management approaches representative of intensive and extensive production systems. One group of 6 Charolais steers was fed maize-silage indoors and another group of 6 Charolais steers grazed on pasture. Activities of enzymes representative of glycolytic and oxidative (Isocitrate dehydrogenase [ICDH], citrate synthase [CS], hydroxyacyl-CoA dehydrogenase [HAD]) muscle metabolism were assessed in Rectus abdominis (RA) and Semitendinosus (ST) muscles. Activities of oxidative enzymes ICDH, CS and HAD were higher in muscles from grazing animals demonstrating a plasticity of muscle metabolism according to the production and feeding system. Gene expression profiling in RA and ST muscles was performed on both production groups using a multi-tissue bovine cDNA repertoire. Variance analysis showed an effect of the muscle type and of the production system on gene expression (P<0.001). A list of the 212 most variable genes according to the production system was established, of which 149 genes corresponded to identified genes. They were classified according to their gene function annotation mainly in the "protein metabolism and modification", "signal transduction", "cell cycle", "developmental processes" and "muscle contraction" biological processes. Selenoprotein W was found to be underexpressed in pasture-fed animals and could be proposed as a putative gene marker of the grass-based system. In conclusion, enzyme-specific adaptations and gene expression modifications were observed in response to the production system and some of them could be candidates for grazing or grass-feeding traceability.

  3. Diet Selection and Grazing Behavior

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Grazing behavior and diet selection of grazing ruminants can be influenced by a lot of factors. Firstly, they learn from their dams. Secondly, they learn from peers. Thirdly, they learn by trial and error. Work at our USDA-ARS lab showed that ‘ruminal fill’, or how ‘hungry’ the cow is, can affect gr...

  4. How Supplementation Affects Grazing Behavior

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Researchers are still in the early stages of understanding how supplementation affects grazing behavior. Conventional nutrition wisdom, including early research with grazing cattle, has been based almost entirely upon stored feeds fed in confinement. In these situations, most dietary “choices” were ...

  5. Assessment of Grazing Effect on Sheep Fescue (Festuca valesiaca)Dominated Steppe Rangelands in the semi-arid Central Anatolian Region of Turkey

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Because of increased grazing pressure over the last fifty years, vegetation of the steppe rangelands in the semi-arid Central Anatolian Region of Turkey has been severely degraded. In these pastures, Festuca valesiaca (a sod forming short-grass) and Thymus sipyleus ssp rosulans (a prostrate shrub) a...

  6. Biosolids and dredged materials: alternative sources of nutrients for crop productivity and sustainability of pasture-based agroecosystem

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Domestic sewage sludge or “biosolids” and lake-dredged materials are examples of materials that can be used to cut fertilizer costs in pasture-based animal agriculture. Sustainable biosolids and lake-dredged materials management is based upon controlling and influencing the quantity, quality and cha...

  7. Influence of flue gas desulfurization gypsum on reducing soluble phosphorus in successive runoff events from a coastal plain bermudagrass pasture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Controlling the potential threat that pasture systems which have been intensively fertilized with poultry litter (PL) pose to accelerate eutrophication of surface waters has become a major issue in the southeastern U.S. Gypsum has been identified as a promising management tool for ameliorating the ...

  8. Productive responses of breeding Cashmere goats and their kids to different stocking rates on improved upland pastures.

    PubMed

    Celaya, R; Moreno-Gonzalo, J; López López, C; Ferreira, L M M; García, U; Ferre, I; Osoro, K

    2016-03-01

    Although goat meat production could be an option for diversification in improved upland pastures in northern Spain, precise information on the optimal grazing management to enhance goat performance and maximize production per unit land area is lacking. The objective of this study was to compare the effects of 3 stocking rates, high stocking rate (HSR; 20 goats/ha), medium stocking rate (MSR; 15 goats/ha), and low stocking rate (LSR; 10 goats/ha), on gastrointestinal (GI) nematode infections and productive responses of Cashmere goats grazing such pastures. Treatments were replicated twice on 6 paddocks sown with and and with a high presence of the native grass . The experiment lasted 3 grazing seasons (from spring to autumn). Pastures were sampled for sward height and botanical and proximate composition. Body weight and BCS changes of goats were monitored and GI nematode infections were assessed by fecal egg counts (FEC). The established treatments resulted in lower mean sward height in the HSR than in the MSR and LSR (9.6, 11.5, and 14.4 cm, respectively; < 0.001). Pasture botanical composition and nutritive quality did not differ between treatments. The mean FEC of does across the 3 grazing seasons were greater ( < 0.05) in the HSR than in the LSR. spp., , and were the most prevalent nematode species identified in coprocultures. Does showed more favorable ( < 0.001) BW and BCS changes in the LSR than in the MSR and HSR (-14, -30, and -52 g/d and -0.1, -0.3, and -0.7 BCS units [scale 1 to 5], respectively). Greater ( < 0.001) kids' BW gains were observed in the LSR and MSR (average 94 g/d) compared with the HSR (70 g/d). Inversely, kid output per unit land area was greater in the HSR than in the MSR and LSR (320, 258, and 192 kg∙ha∙yr, respectively; < 0.001), whereas daily kids' BW gains per hectare were greater ( < 0.001) in the HSR and MSR (average 1.37 kg∙d∙ha) compared with the LSR (0.98 kg∙d∙ha). A medium stocking rate of 15 goats/ha could

  9. Grazing incidence beam expander

    SciTech Connect

    Akkapeddi, P.R.; Glenn, P.; Fuschetto, A.; Appert, Q.; Viswanathan, V.K.

    1985-01-01

    A Grazing Incidence Beam Expander (GIBE) telescope is being designed and fabricated to be used as an equivalent end mirror in a long laser resonator cavity. The design requirements for this GIBE flow down from a generic Free Electron Laser (FEL) resonator. The nature of the FEL gain volume (a thin, pencil-like, on-axis region) dictates that the output beam be very small. Such a thin beam with the high power levels characteristic of FELs would have to travel perhaps hundreds of meters or more before expanding enough to allow reflection from cooled mirrors. A GIBE, on the other hand, would allow placing these optics closer to the gain region and thus reduces the cavity lengths substantially. Results are presented relating to optical and mechanical design, alignment sensitivity analysis, radius of curvature analysis, laser cavity stability analysis of a linear stable concentric laser cavity with a GIBE. Fabrication details of the GIBE are also given.

  10. Conversion from forests to pastures in the Colombian Amazon leads to contrasting soil carbon dynamics depending on land management practices.

    PubMed

    Navarrete, Diego; Sitch, Stephen; Aragão, Luiz E O C; Pedroni, Lucio

    2016-10-01

    Strategies to mitigate climate change by reducing deforestation and forest degradation (e.g. REDD+) require country- or region-specific information on temporal changes in forest carbon (C) pools to develop accurate emission factors. The soil C pool is one of the most important C reservoirs, but is rarely included in national forest reference emission levels due to a lack of data. Here, we present the soil organic C (SOC) dynamics along 20 years of forest-to-pasture conversion in two subregions with different management practices during pasture establishment in the Colombian Amazon: high-grazing intensity (HG) and low-grazing intensity (LG) subregions. We determined the pattern of SOC change resulting from the conversion from forest (C3 plants) to pasture (C4 plants) by analysing total SOC stocks and the natural abundance of the stable isotopes (13) C along two 20-year chronosequences identified in each subregion. We also analysed soil N stocks and the natural abundance of (15) N during pasture establishment. In general, total SOC stocks at 30 cm depth in the forest were similar for both subregions, with an average of 47.1 ± 1.8 Mg C ha(-1) in HG and 48.7 ± 3.1 Mg C ha(-1) in LG. However, 20 years after forest-to-pasture conversion SOC in HG decreased by 20%, whereas in LG SOC increased by 41%. This net SOC decrease in HG was due to a larger reduction in C3-derived input and to a comparatively smaller increase in C4-derived C input. In LG both C3- and C4-derived C input increased along the chronosequence. N stocks were generally similar in both subregions and soil N stock changes during pasture establishment were correlated with SOC changes. These results emphasize the importance of management practices involving low-grazing intensity in cattle activities to preserve SOC stocks and to reduce C emissions after land-cover change from forest to pasture in the Colombian Amazon.

  11. Conversion from forests to pastures in the Colombian Amazon leads to contrasting soil carbon dynamics depending on land management practices.

    PubMed

    Navarrete, Diego; Sitch, Stephen; Aragão, Luiz E O C; Pedroni, Lucio

    2016-10-01

    Strategies to mitigate climate change by reducing deforestation and forest degradation (e.g. REDD+) require country- or region-specific information on temporal changes in forest carbon (C) pools to develop accurate emission factors. The soil C pool is one of the most important C reservoirs, but is rarely included in national forest reference emission levels due to a lack of data. Here, we present the soil organic C (SOC) dynamics along 20 years of forest-to-pasture conversion in two subregions with different management practices during pasture establishment in the Colombian Amazon: high-grazing intensity (HG) and low-grazing intensity (LG) subregions. We determined the pattern of SOC change resulting from the conversion from forest (C3 plants) to pasture (C4 plants) by analysing total SOC stocks and the natural abundance of the stable isotopes (13) C along two 20-year chronosequences identified in each subregion. We also analysed soil N stocks and the natural abundance of (15) N during pasture establishment. In general, total SOC stocks at 30 cm depth in the forest were similar for both subregions, with an average of 47.1 ± 1.8 Mg C ha(-1) in HG and 48.7 ± 3.1 Mg C ha(-1) in LG. However, 20 years after forest-to-pasture conversion SOC in HG decreased by 20%, whereas in LG SOC increased by 41%. This net SOC decrease in HG was due to a larger reduction in C3-derived input and to a comparatively smaller increase in C4-derived C input. In LG both C3- and C4-derived C input increased along the chronosequence. N stocks were generally similar in both subregions and soil N stock changes during pasture establishment were correlated with SOC changes. These results emphasize the importance of management practices involving low-grazing intensity in cattle activities to preserve SOC stocks and to reduce C emissions after land-cover change from forest to pasture in the Colombian Amazon. PMID:26929394

  12. Predicting greenhouse gas emissions and soil carbon from changing pasture to an energy crop.

    PubMed

    Duval, Benjamin D; Anderson-Teixeira, Kristina J; Davis, Sarah C; Keogh, Cindy; Long, Stephen P; Parton, William J; DeLucia, Evan H

    2013-01-01

    Bioenergy related land use change would likely alter biogeochemical cycles and global greenhouse gas budgets. Energy cane (Saccharum officinarum L.) is a sugarcane variety and an emerging biofuel feedstock for cellulosic bio-ethanol production. It has potential for high yields and can be grown on marginal land, which minimizes competition with grain and vegetable production. The DayCent biogeochemical model was parameterized to infer potential yields of energy cane and how changing land from grazed pasture to energy cane would affect greenhouse gas (CO2, CH4 and N2O) fluxes and soil C pools. The model was used to simulate energy cane production on two soil types in central Florida, nutrient poor Spodosols and organic Histosols. Energy cane was productive on both soil types (yielding 46-76 Mg dry mass · ha(-1)). Yields were maintained through three annual cropping cycles on Histosols but declined with each harvest on Spodosols. Overall, converting pasture to energy cane created a sink for GHGs on Spodosols and reduced the size of the GHG source on Histosols. This change was driven on both soil types by eliminating CH4 emissions from cattle and by the large increase in C uptake by greater biomass production in energy cane relative to pasture. However, the change from pasture to energy cane caused Histosols to lose 4493 g CO2 eq · m(-2) over 15 years of energy cane production. Cultivation of energy cane on former pasture on Spodosol soils in the southeast US has the potential for high biomass yield and the mitigation of GHG emissions.

  13. Predicting Greenhouse Gas Emissions and Soil Carbon from Changing Pasture to an Energy Crop

    PubMed Central

    Duval, Benjamin D.; Anderson-Teixeira, Kristina J.; Davis, Sarah C.; Keogh, Cindy; Long, Stephen P.; Parton, William J.; DeLucia, Evan H.

    2013-01-01

    Bioenergy related land use change would likely alter biogeochemical cycles and global greenhouse gas budgets. Energy cane (Saccharum officinarum L.) is a sugarcane variety and an emerging biofuel feedstock for cellulosic bio-ethanol production. It has potential for high yields and can be grown on marginal land, which minimizes competition with grain and vegetable production. The DayCent biogeochemical model was parameterized to infer potential yields of energy cane and how changing land from grazed pasture to energy cane would affect greenhouse gas (CO2, CH4 and N2O) fluxes and soil C pools. The model was used to simulate energy cane production on two soil types in central Florida, nutrient poor Spodosols and organic Histosols. Energy cane was productive on both soil types (yielding 46–76 Mg dry mass⋅ha−1). Yields were maintained through three annual cropping cycles on Histosols but declined with each harvest on Spodosols. Overall, converting pasture to energy cane created a sink for GHGs on Spodosols and reduced the size of the GHG source on Histosols. This change was driven on both soil types by eliminating CH4 emissions from cattle and by the large increase in C uptake by greater biomass production in energy cane relative to pasture. However, the change from pasture to energy cane caused Histosols to lose 4493 g CO2 eq⋅m−2 over 15 years of energy cane production. Cultivation of energy cane on former pasture on Spodosol soils in the southeast US has the potential for high biomass yield and the mitigation of GHG emissions. PMID:23991028

  14. The GEOGLAM Rangelands and Pasture Productivity Activity: Recent Progress and Future Directions

    NASA Astrophysics Data System (ADS)

    Guerschman, J. P.; Held, A. A.; Donohue, R. J.; Renzullo, L. J.; Sims, N.; Kerblat, F.; Grundy, M.

    2015-12-01

    Rangelands and pastures cover about a third of the world's land area and support livestock production which represents ~40% of global agricultural gross domestic product. The global consumption of animal protein shows a clear increasing trend, driven by both total population and per capita income increases, putting a growing pressure on the sustainability of grazing lands worldwide. Despite their relevance, rangelands have received less attention than croplands regarding global monitoring of the resource productivity and condition. The Rangelands and Pasture Productivity (RaPP) activity is a component within the Global Agricultural Monitoring initiative established under the Group on Earth Observations (GEOGLAM) in 2013. GEOGLAM RaPP is aimed at providing the global community with the means to monitor the world's rangelands and pastures on a routine basis, and the capacity to produce animal protein in real-time, at global, regional and national levels. Since its launch two years ago GEOGLAM RAPP has made progress in the four implementation elements. These include: 1- the establishment of community of practice; 2- the development of a global monitoring system for rangeland condition; 3- the establishment of pilot sites in main rangeland systems for satellite data products validation and model testing; and 4- integration with livestock production models. Three international workshops have been held building the community of practice. A prototype monitoring system that provides global visualisations and querying capability of vegetation cover data and anomalies has been established. Pilot sites, mostly in areas with long records of field measurements of rangeland condition and productivity have been proposed for nine countries. The link to global livestock models, including physical and economic components, have been established. Future challenges for GEOGLAM RaPP have also been identified and include: better representation of the areas occupied by rangelands

  15. Underlying Ecosystem Methane Emissions Exceed Cattle-Derived Methane from Subtropical Lowland Pastures.

    NASA Astrophysics Data System (ADS)

    Chamberlain, S. D.; Sparks, J. P.

    2014-12-01

    Grazing cattle are a major methane (CH4) source from pasture ecosystems, however the underlying landscape is a potentially significant CH4 source that has received far less attention. Ecosystem surface emissions of CH4 are poorly quantified, vary widely across time and space, and are easily underestimated if emission hotspots or episodic fluxes are overlooked. We used static chambers, eddy covariance, and mobile cavity-ringdown spectrometry surveys to quantify spatially and temporally variable CH4 emissions from subtropical lowland pastures. We conclude emissions from soil and standing water are the dominant CH4 source, and cattle were responsible for only 13% of annual CH4emissions. The ecosystem emit 33.8 ± 2.2 g CH4 m-2 yr-1, however surface CH4 emissions were highly variable in both time and space. Seasonal flooding of pastures and low-lying landforms (canals, ditches, wetlands) drove high magnitude CH4 emissions. We observed large CH4 emissions from wetlands and, to a lesser extent, the entire landscape during the wet season. In contrast, during the dry season there was no appreciable CH4 accumulation in pastures when cattle were not present, and canals, which comprise 1.7% of the total land area, were responsible 97.7 % of dry season emissions. Ecosystem CH4 fluxes, measured by eddy covariance, varied seasonally and positively correlated to soil and air temperature, topsoil water content, and water table depth. Our work is the first to use mobile spectrometers to map biogenic CH4 emissions at the landscape scale, and demonstrates that soils and water are a strong pasture CH4 source that must be considered in addition to cattle emissions.

  16. Biogeochemical and ecological impacts of livestock grazing in semi-arid southeastern Utah, USA

    USGS Publications Warehouse

    Fernandez, D.P.; Neff, J.C.; Reynolds, R.L.

    2008-01-01

    Relatively few studies have examined the ecological and biogeochemical effects of livestock grazing in southeastern Utah. In this study, we evaluated how grazing has affected soil organic carbon and nitrogen to a depth of 50 cm in grasslands located in relict and actively-grazed sites in the Canyonlands physiographic section of the Colorado Plateau. We also evaluated differences in plant ground cover and the spatial distribution of soil resources. Results show that areas used by domestic livestock have 20% less plant cover and 100% less soil organic carbon and nitrogen compared to relict sites browsed by native ungulates. In actively grazed sites, domestic livestock grazing also appears to lead to clustered, rather than random, spatial distribution of soil resources. Magnetic susceptibility, a proxy for soil stability in this region, suggests that grazing increases soil erosion leading to an increase in the area of nutrient-depleted bare ground. Overall, these results, combined with previous studies in the region, suggest that livestock grazing affects both plant cover and soil fertility with potential long-term implications for the sustainability of grazing operations in this semi-arid landscape. ?? 2007 Elsevier Ltd. All rights reserved.

  17. Benthic macroinvertebrate responses to increasing levels of cattle grazing in Blue Ridge Mountain streams, Virginia, USA.

    PubMed

    Braccia, Amy; Voshell, J Reese

    2007-08-01

    The relationship between benthic macroinvertebrate assemblages and cattle density was assessed from fall 2002 through spring 2004 in five small streams that represented a gradient of cattle grazing intensity. All study stream reaches were in pasture with no woody riparian vegetation, but varied in the intensity of cattle grazing (0 cattle ha(-1) at site 1 to 2.85 cattle ha(-1) at site 5). Regression analysis indicated highly significant and strong macroinvertebrate metric responses to cattle density during most sampling periods. The majority of metrics responded negatively to increased grazing, while a few (total taxa richness, number of sensitive taxa, and % collector filterers) increased along the gradient before declining at the most heavily grazed sites. Total number of sensitive taxa and % Coleoptera had the strongest relationship with cattle density throughout the study period. During some sampling periods, nearly 80% of the variation in these metrics was explained by cattle density. The elmid beetle, Oulimnius, had a particularly strong negative response to the grazing gradient. Study site groupings based on taxa composition, using detrended correspondence analysis (DCA), indicated that benthic samples collected from the reference site and light rotational grazing site were more similar in macroinvertebrate taxa composition than samples collected from the intermediate grazing and heavy grazing sites. Our findings demonstrate that biological integrity, as measured by benthic macroinvertebrate metrics and assemblage composition, is highly related to cattle density in small streams in the Blue Ridge mountains, Virginia, USA. This suggests that the degree of agricultural intensity should be given consideration in stream assessments, as well as land use planning and regulatory decisions.

  18. Sward characteristics and performance of dairy cows in organic grass-legume pastures shaded by tropical trees.

    PubMed

    Paciullo, D S C; Pires, M F A; Aroeira, L J M; Morenz, M J F; Maurício, R M; Gomide, C A M; Silveira, S R

    2014-08-01

    The silvopastoral system (SPS) has been suggested to ensure sustainability in animal production systems in tropical ecosystems. The objective of this study was to evaluate pasture characteristics, herbage intake, grazing activity and milk yield of Holstein×Zebu cows managed in two grazing systems (treatments): SPS dominated by a graminaceous forage (Brachiaria decumbens) intercropped with different leguminous herbaceous forages (Stylosanthes spp., Pueraria phaseoloides and Calopogonium mucunoides) and legume trees (Acacia mangium, Gliricidia sepium and Leucaena leucocephala), and open pasture (OP) of B. decumbens intercropped only with Stylosanthes spp. Pastures were managed according to the rules for organic cattle production. The study was carried out by following a switch back format with 12 cows, 6 for each treatment, over 3 experimental years. Herbage mass was similar (P>0.05) for both treatments, supporting an average stocking rate of 1.23 AU/ha. Daily dry matter intake did not vary (P>0.05) between treatments (average of 11.3±1.02 kg/cow per day, corresponding to 2.23±0.2% BW). Milk yield was higher (P0.05) in subsequent years. The highest (P0.05) milk yields. Low persistence of Stylosanthes guianensis was observed over the experimental period, indicating that the persistence of forage legumes under grazing could be improved using adapted cultivars that have higher annual seed production. The SPS and a diversified botanical composition of the pasture using legume species mixed with grasses are recommended for organic milk production. PMID:24703358

  19. 25 CFR 167.9 - Grazing permits.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Grazing permits. 167.9 Section 167.9 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER NAVAJO GRAZING REGULATIONS § 167.9 Grazing permits. (a) All livestock grazed on the Navajo Reservation must be covered by an authorized...

  20. 25 CFR 167.9 - Grazing permits.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Grazing permits. 167.9 Section 167.9 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER NAVAJO GRAZING REGULATIONS § 167.9 Grazing permits. (a) All livestock grazed on the Navajo Reservation must be covered by an authorized...

  1. 25 CFR 167.9 - Grazing permits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Grazing permits. 167.9 Section 167.9 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER NAVAJO GRAZING REGULATIONS § 167.9 Grazing permits. (a) All livestock grazed on the Navajo Reservation must be covered by an authorized...

  2. 25 CFR 167.9 - Grazing permits.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Grazing permits. 167.9 Section 167.9 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER NAVAJO GRAZING REGULATIONS § 167.9 Grazing permits. (a) All livestock grazed on the Navajo Reservation must be covered by an authorized...

  3. 25 CFR 167.8 - Grazing rights.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Grazing rights. 167.8 Section 167.8 Indians BUREAU OF... rights. (a) The Superintendent shall determine grazing rights of bona fide live-stock owners based on recommendations of District Grazing Committees. Grazing rights shall be recognized for those permittees...

  4. Permanent, biodiverse pastures in Montado ecosystems - biogeochemical and physiological implications for cork oak trees

    NASA Astrophysics Data System (ADS)

    Moura, C.; Dawson, T. E.; Santos Pereira, J.

    2012-12-01

    Sown biodiverse permanent pastures rich in legumes (SBPPRL) have been implemented in Portugal as a management tool to increase soil fertility, grassland productivity and animal carrying capacity and were later selected as a voluntary land-use change activity towards increased carbon sequestration within the context of the Kyoto protocol. SBPPRL are commonly found in the understory of Mediterranean-type agro-silvo-pastoral systems - Montados - with cork oak as a dominant tree species. However, little is known about the effects of these introduced pastures on co-occurring cork oak physiology and productivity. Understanding the impact of grassland conversion on carbon, water, and nutrient cycling - namely at the tree level - could be of great importance for future management and policy decisions. Cork oak trees growing in an LTER, flux-tower site in Southern Portugal have been selected among two types of understory land-use: natural grassland and sown biodiverse permanent pasture. A suite of leaf-based physiological and morphological parameters were measured in cork oak trees across both land-use scenarios and different seasons. Here we focus on the results from foliar 15δN and 13δC between spring and summer. 13δC ranged from-30.21 to -27.36, with an average value of -28.74 (± 0.12) and no significant differences found between pasture types (natural vs. improved) or time (spring vs. summer). Foliar 15δN on the other hand showed statistically significant differences between cork oaks in different pasture types (-2.96±0.09 natural vs. -2.21±0.17 improved pastures, t-test, p ≤ 0.05), but no differences across time points. Cork oak trees in the permanent pasture have a 15δN signature closer to zero, consistent with a higher percentage of legumes (and N2 fixation) in that system. Using a mixed-model approach we estimated these trees to be using ca. 25% of their nitrogen from legume-fixation in the pasture. Despite the clear signature influence of legume-fixed N

  5. Plant Species Diversity and Pasture Management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Farmers face many challenges in pasture management, such as evolving agri-environmental schemes to protect natural resources, and need new management techniques to remain sustainable. Ecological research indicates that increased plant biodiversity benefits ecosystem functions such as primary product...

  6. Increased stocking rate and associated strategic dry-off decision rules reduced the amount of nitrate-N leached under grazing.

    PubMed

    Roche, J R; Ledgard, S F; Sprosen, M S; Lindsey, S B; Penno, J W; Horan, B; Macdonald, K A

    2016-07-01

    The effect of intensive agricultural systems on the environment is of increasing global concern, and recent review articles have highlighted the need for sustainable intensification of food production. In grazing dairy systems, the leaching of nitrate-N (NO3-N) to groundwater is a primary environmental concern. A herd-level factor considered by many to be a key contributor to the amount of NO3-N leached from dairy pastures is stocking rate (SR), and some countries have imposed limits to reduce the risk of NO3-N loss to groundwater. The objective of the current experiment was to determine the effect of dairy cow SR on NO3-N leached in a grazing system that did not import feed from off-farm and had the same N fertilizer input. Five SR were evaluated (2.2, 2.7, 3.1, 3.7, and 4.3 cows/ha) in a completely randomized design (i.e., 2 replicates of each SR as independent farmlets) over 2 y. Pasture utilization, milk production/hectare, and days in milk/hectare increased with SR, but days in milk/cow and milk production/cow declined. The concentration of NO3-N in drainage water and the quantity of NO3-N leached/ha per year declined linearly with increasing SR, and the operating profit/kg NO3-N leached per ha increased. Higher SR was associated with fewer days in milk/cow, resulting in a reduction in estimated urine N excretion/cow (the main source of N leaching) during the climatically sensitive period for NO3-N leaching (i.e., late summer to winter). We hypothesized that the reduction in estimated urine N excretion per cow led to an increase in urinary N spread and reduced losses from urine patches. The results presented indicate that lowering SR may not reduce nitrate leaching and highlight the need for a full farm system-level analysis of any management change to determine its effect on productivity and environmental outcomes. PMID:27157574

  7. Increased stocking rate and associated strategic dry-off decision rules reduced the amount of nitrate-N leached under grazing.

    PubMed

    Roche, J R; Ledgard, S F; Sprosen, M S; Lindsey, S B; Penno, J W; Horan, B; Macdonald, K A

    2016-07-01

    The effect of intensive agricultural systems on the environment is of increasing global concern, and recent review articles have highlighted the need for sustainable intensification of food production. In grazing dairy systems, the leaching of nitrate-N (NO3-N) to groundwater is a primary environmental concern. A herd-level factor considered by many to be a key contributor to the amount of NO3-N leached from dairy pastures is stocking rate (SR), and some countries have imposed limits to reduce the risk of NO3-N loss to groundwater. The objective of the current experiment was to determine the effect of dairy cow SR on NO3-N leached in a grazing system that did not import feed from off-farm and had the same N fertilizer input. Five SR were evaluated (2.2, 2.7, 3.1, 3.7, and 4.3 cows/ha) in a completely randomized design (i.e., 2 replicates of each SR as independent farmlets) over 2 y. Pasture utilization, milk production/hectare, and days in milk/hectare increased with SR, but days in milk/cow and milk production/cow declined. The concentration of NO3-N in drainage water and the quantity of NO3-N leached/ha per year declined linearly with increasing SR, and the operating profit/kg NO3-N leached per ha increased. Higher SR was associated with fewer days in milk/cow, resulting in a reduction in estimated urine N excretion/cow (the main source of N leaching) during the climatically sensitive period for NO3-N leaching (i.e., late summer to winter). We hypothesized that the reduction in estimated urine N excretion per cow led to an increase in urinary N spread and reduced losses from urine patches. The results presented indicate that lowering SR may not reduce nitrate leaching and highlight the need for a full farm system-level analysis of any management change to determine its effect on productivity and environmental outcomes.

  8. Variation in feeding behavior and milk production among dairy cows when supplemented with 2 amounts of mixed ration in combination with 2 amounts of pasture.

    PubMed

    Wright, M M; Auldist, M J; Kennedy, E; Dunshea, F R; Hannah, M; Wales, W J

    2016-08-01

    Variation in feeding behavior and milk production of grazing dairy cows fed a mixed ration was measured. Experiments were conducted in spring (early lactation) and autumn (late lactation) with 48 Holstein-Friesian dairy cows. Pasture allowance (low vs. high) and amounts of supplement (low vs. high) were applied to determine the effect on variation among cows in feeding behavior and milk production. The experiments investigated 4 dietary treatments in a 2×2 factorial arrangement of treatments. Daily pasture allowances were 15kg of DM/cow per day (low) and 37kg of DM/cow per day (high; to ground level); and 12kg of DM/cow per day (low) and 31kg of DM/cow per day (high; to ground level), for the spring and autumn experiments, respectively. Supplements were offered at 6kg of DM/cow per day (low) and 14kg of DM/cow per day (high); and 6kg of DM/cow per day (low) and 12kg of DM/cow per day (high), for the spring and autumn experiments, respectively. There were 2groups of 6 cows per treatment. All treatments received a partial mixed ration, defined as a total mixed ration fed between periods of grazing that contained wheat grain, corn grain, alfalfa hay, and canola meal. The grain-to-forage ratio of the supplements was 78:22 (DM basis) in both spring and autumn. In both experiments, the pre-experimental period was 14d followed by a 10-d experimental period. The variation among cows within a group in feeding behavior was influenced by the amount of supplement but not the amount of pasture offered. The variation among cows in pasture eating time approximately doubled when the amount of supplement offered increased, indicating that to reduce the variability among cows, supplement feeding management strategies need to be considered. Increasing pasture allowance had no effect on pasture eating time although pasture intake increased as a result of increased grazing intensity compared with the low pasture allowance. However, increasing the amount of supplement in the partial

  9. Response of vegetation and soil carbon and nitrogen storage to grazing intensity in semi-arid grasslands in the agro-pastoral zone of northern china.

    PubMed

    Xu, Min-Yun; Xie, Fan; Wang, Kun

    2014-01-01

    Overgrazing has been the primary cause of grassland degradation in the semi-arid grasslands of the agro-pastoral transition zone in northern China. However, there has been little evidence regarding grazing intensity impacts on vegetation change and soil C and N dynamics in this region. This paper reports the effects of four grazing intensities namely un-grazed (UG), lightly grazed (LG), moderately grazed (MG) and heavily grazed (HG) on vegetation characteristics and soil properties of grasslands in the Guyuan county in the agro-pastoral transition region, Hebei province, northern China. Our study showed that the vegetation height, canopy cover, plant species abundance and aboveground biomass decreased significantly with increased grazing intensity. Similarly, soil organic carbon (SOC) and total nitrogen (STN) in the 0-50 cm were highest under UG (13.3 kg C m-2 and 1.69 kg N m-2) and lowest under HG (9.8 kg C m-2 and 1.22 kg N m-2). Soil available nitrogen (SAN) was significantly lower under HG (644 kg N hm-2) than under other treatments (725-731 kg N hm-2) in the 0-50 cm. Our results indicate that the pasture management of "take half-leave half" has potential benefits for primary production and livestock grazing in this region. However, grazing exclusion was perhaps the most effective choice for restoring degraded grasslands in this region. Therefore, flexible rangeland management should be adopted in this region. PMID:24819162

  10. Response of Vegetation and Soil Carbon and Nitrogen Storage to Grazing Intensity in Semi-Arid Grasslands in the Agro-Pastoral Zone of Northern China

    PubMed Central

    Xu, Min-yun; Xie, Fan; Wang, Kun

    2014-01-01

    Overgrazing has been the primary cause of grassland degradation in the semi-arid grasslands of the agro-pastoral transition zone in northern China. However, there has been little evidence regarding grazing intensity impacts on vegetation change and soil C and N dynamics in this region. This paper reports the effects of four grazing intensities namely un-grazed (UG), lightly grazed (LG), moderately grazed (MG) and heavily grazed (HG) on vegetation characteristics and soil properties of grasslands in the Guyuan county in the agro-pastoral transition region, Hebei province, northern China. Our study showed that the vegetation height, canopy cover, plant species abundance and aboveground biomass decreased significantly with increased grazing intensity. Similarly, soil organic carbon (SOC) and total nitrogen (STN) in the 0–50 cm were highest under UG (13.3 kg C m−2 and 1.69 kg N m−2) and lowest under HG (9.8 kg C m−2 and 1.22 kg N m−2). Soil available nitrogen (SAN) was significantly lower under HG (644 kg N hm−2) than under other treatments (725–731 kg N hm−2) in the 0–50 cm. Our results indicate that the pasture management of “take half-leave half” has potential benefits for primary production and livestock grazing in this region. However, grazing exclusion was perhaps the most effective choice for restoring degraded grasslands in this region. Therefore, flexible rangeland management should be adopted in this region. PMID:24819162

  11. Milk production responses to different strategies for feeding supplements to grazing dairy cows.

    PubMed

    Auldist, M J; Marett, L C; Greenwood, J S; Wright, M M; Hannah, M; Jacobs, J L; Wales, W J

    2016-01-01

    Milk production responses of grazing cows offered supplements in different ways were measured. Holstein-Friesian cows, averaging 45 d in milk, were allocated into 8 groups of 24, with 2 groups randomly assigned to each of 4 feeding strategies. These were control: cows grazed a restricted allowance of perennial ryegrass pasture supplemented with milled wheat grain fed in the milking parlor and alfalfa hay offered in the paddock; FGM: same pasture and allowance as the control supplemented with a formulated grain mix containing wheat grain, corn grain, and canola meal fed in the parlor and alfalfa hay fed in the paddock; PMRL: same pasture and allowance as the control, supplemented with a PMR consisting of the same FGM but mixed with alfalfa hay and presented on a feed pad after each milking; and PMRH: same PMR fed in the same way as PMRL but with a higher pasture allowance. For all strategies, supplements provided the same metabolizable energy and grain:forage ratio [75:25, dry matter (DM) basis]. Each group of 24 cows was further allocated into 4 groups of 6, which were randomly assigned to receive 8, 12, 14, or 16 kg of DM supplement/cow per d. Thus, 2 replicated groups per supplement amount per dietary strategy were used. The experiment had a 14-d adaptation period and a 14-d measurement period. Pasture allowance, measured to ground level, was approximately 14 kg of DM/d for control, FGM, and PMRL cows, and 28 kg of DM/d for the PMRH cows, and was offered in addition to the supplement. Positive linear responses to increasing amounts of supplement were observed for yield of milk, energy-corrected milk, fat, and protein for cows on all 4 supplement feeding strategies. Production of energy-corrected milk was greatest for PMRH cows, intermediate for FGM and PMRL cows, and lowest for control cows. Some of these differences in milk production related to differences in intake of pasture and supplement. Milk fat concentration decreased with increasing amount of supplement

  12. Milk production responses to different strategies for feeding supplements to grazing dairy cows.

    PubMed

    Auldist, M J; Marett, L C; Greenwood, J S; Wright, M M; Hannah, M; Jacobs, J L; Wales, W J

    2016-01-01

    Milk production responses of grazing cows offered supplements in different ways were measured. Holstein-Friesian cows, averaging 45 d in milk, were allocated into 8 groups of 24, with 2 groups randomly assigned to each of 4 feeding strategies. These were control: cows grazed a restricted allowance of perennial ryegrass pasture supplemented with milled wheat grain fed in the milking parlor and alfalfa hay offered in the paddock; FGM: same pasture and allowance as the control supplemented with a formulated grain mix containing wheat grain, corn grain, and canola meal fed in the parlor and alfalfa hay fed in the paddock; PMRL: same pasture and allowance as the control, supplemented with a PMR consisting of the same FGM but mixed with alfalfa hay and presented on a feed pad after each milking; and PMRH: same PMR fed in the same way as PMRL but with a higher pasture allowance. For all strategies, supplements provided the same metabolizable energy and grain:forage ratio [75:25, dry matter (DM) basis]. Each group of 24 cows was further allocated into 4 groups of 6, which were randomly assigned to receive 8, 12, 14, or 16 kg of DM supplement/cow per d. Thus, 2 replicated groups per supplement amount per dietary strategy were used. The experiment had a 14-d adaptation period and a 14-d measurement period. Pasture allowance, measured to ground level, was approximately 14 kg of DM/d for control, FGM, and PMRL cows, and 28 kg of DM/d for the PMRH cows, and was offered in addition to the supplement. Positive linear responses to increasing amounts of supplement were observed for yield of milk, energy-corrected milk, fat, and protein for cows on all 4 supplement feeding strategies. Production of energy-corrected milk was greatest for PMRH cows, intermediate for FGM and PMRL cows, and lowest for control cows. Some of these differences in milk production related to differences in intake of pasture and supplement. Milk fat concentration decreased with increasing amount of supplement

  13. From rags to riches: the story of carbon, nutrients and pasture with dairy compost application

    NASA Astrophysics Data System (ADS)

    Drake, Jess; Cavagnaro, Tim; Patti, Tony; Wilkinson, Kevin; McDonald, Declan; Johnston, Priscilla; Wilson, Katrina; Rose, Mick; Jackson, Roy

    2014-05-01

    Around the world, dairy farmers are transforming dairy waste to compost for land application. In southeastern Australia, farmers are using composted dairy waste to increase production and reduce costs. In addition, the farmers are considering the benefits of compost for increasing sequestration of soil carbon, and on-farm nutrient retention. The "Carbon Farming Initative" in Australia is exploring the option to allow farmers to trade Carbon Credits for carbon stored in the soil. Compost also retains vital nutrients, such as N, on farm rather than importing N in the form of mineral fertilisers. Composting also reduces greenhouse gas emissions, such as CH4, compared to when stored in effluent ponds. This project will investigate if dairy compost applied to pasture improves carbon sequestration, nutrient retention and pasture production. In this project dairy compost, made from dairy effluent, feedpad waste, spoilt sillage and wood mulch, was applied onto a 1Ha field and companion plots at a rate of 0, 3, 6 and 12 t/ha. The field plot is open to grazing and normal farm management practices. The companion plots are being subjected to simulated grazing (mowing). The trials, currently underway will run for 18 months. Along with preliminary soil carbon results, this work will also include preliminary data for total and plant available nutrients, and farm biomass production. The outcomes of this research, and benefits it finds for "Carbon Farming" and nutrient retention has practical, policy and economic applications for world wide markets.

  14. Development of secondary woodland in oak wood pastures reduces the richness of rare epiphytic lichens.

    PubMed

    Paltto, Heidi; Nordberg, Anna; Nordén, Björn; Snäll, Tord

    2011-01-01

    Wooded pastures with ancient trees were formerly abundant throughout Europe, but during the last century, grazing has largely been abandoned often resulting in dense forests. Ancient trees constitute habitat for many declining and threatened species, but the effects of secondary woodland on the biodiversity associated with these trees are largely unknown. We tested for difference in species richness, occurrence, and abundance of a set of nationally and regionally red-listed epiphytic lichens between ancient oaks located in secondary woodland and ancient oaks located in open conditions. We refined the test of the effect of secondary woodland by also including other explanatory variables. Species occurrence and abundance were modelled jointly using overdispersed zero-inflated Poisson models. The richness of the red-listed lichens on ancient oaks in secondary woodland was half of that compared with oaks growing in open conditions. The species-level analyses revealed that this was mainly the result of lower occupancy of two of the study species. The tree-level abundance of one species was also lower in secondary woodland. Potential explanations for this pattern are that the study lichens are adapted to desiccating conditions enhancing their population persistence by low competition or that open, windy conditions enhance their colonisation rate. This means that the development of secondary woodland is a threat to red-listed epiphytic lichens. We therefore suggest that woody vegetation is cleared and grazing resumed in abandoned oak pastures. Importantly, this will also benefit the vitality of the oaks.

  15. Soil degradation in semi-arid grasslands due to intensive grazing in Northern China

    NASA Astrophysics Data System (ADS)

    Wiesmeier, M.; Steffens, M.; Kölbl, A.; Kögel-Knabner, I.

    2012-04-01

    organic matter input, destruction of soil aggregates due to enhanced animal trampling associated with mineralization of formerly protected SOM and enhanced soil erosion. The analysis of the spatial distribution of SOM showed a small-scale homogenization of SOM at grazed sites compared with a heterogeneous pattern at ungrazed sites. Apparently, heterogeneously distributed grass tussocks, which act as "islands of fertility" in undisturbed steppe ecosystems, are removed by heavy grazing that in turn deteriorates the accumulation of SOM. We conclude that semi-arid grasslands of Northern China are very susceptible to intensive grazing, which led to a considerable depletion and a spatial homogenization of SOM. Further intensification of the grazing management or an extension into undisturbed boundary areas of the steppe should be prevented.

  16. Simulating modern-day cropland and pasture burning in an Earth system model

    NASA Astrophysics Data System (ADS)

    Rabin, Sam; Malyshev, Sergey; Shevliakova, Elena; Magi, Brian; Pacala, Steve

    2015-04-01

    Throughout the Holocene, humans have extended our influence across a larger and larger fraction of ecosystems, even creating some new ones in the process. Herds of livestock grazing either native vegetation (rangeland) or specially planted species (pasture) have modified huge areas of land. We have even developed new plant species and cultivated them as crops. The extent of our ecosystem modification intensified dramatically with the advent of industrialized agriculture, to the point where cropland and pasture (which will henceforth encompass rangeland as well) now cover over a third of the Earth's land area. One way we have altered the terrestrial biosphere is by intentionally and unintentionally altering fire's frequency, intensity, and seasonal timing. This is especially true for agricultural ecosystems. Because their maintenance and use require a level of human control, cropland and pasture often experience fire regimes substantially different from those of the ecosystems they replaced or what would occur in the absence of active fire management. For example, farmers might burn to prepare land for planting or to dispose of crop residues, and pastoralists often use fire to prevent encroachment of unpalatable woody plants. Due to the vast global extent of agriculture, and considering the myriad ways fire affects the Earth system, it is critical that we understand (a) the ways people manage fire on cropland and pasture and (b) the effects of this management on the Earth system. Earth system models are an ideal tool for examining this kind of question. By simulating the processes within and interactions among the atmosphere, oceans, land, and terrestrial ecosystems, Earth system models allow phenomena such as fire to be examined in their global context. However, while the past fifteen years have seen great progress in the simulation of vegetation fire within Earth system models, the direct human influence via cropland and pasture management burning has been mostly

  17. Supplementing lactating dairy cows fed high-quality pasture with black wattle (Acacia mearnsii) tannin.

    PubMed

    Griffiths, W M; Clark, C E F; Clark, D A; Waghorn, G C

    2013-11-01

    A reduction in urinary nitrogen (N) excretion from dairy cows fed pasture containing a high N concentration in the dry matter (DM) will have environmental benefits, because losses to soil water and air by leachate and nitrous oxides (N2O) will be reduced. Condensed tannins (CT) reduce digestion of N, and provision as a dietary additive could have nutritional benefits for production, but the amount required and the responses to different sources of CT on milk production have not been defined. Two experiments were conducted to evaluate effects of supplementation with CT extracted from black wattle (Acacia mearnsii De Wild.) on milk production and faecal N concentration by lactating dairy cows grazing a vegetative Perennial ryegrass (Lolium perenne L.)-based pasture. In one experiment, CT was administered as a drench, twice daily, to 38 multiparous Holstein-Friesian cows assigned to four treatments; control (CONT, 0 g/day), low CT (LCT, 111 g/day), medium CT (MCT, 222 g/day) and high CT (HCT, 444 g/day), grazing as a single group. The CT supplementation affected milk yield (P < 0.001) with a trend of declining milk yield as CT concentration increased from about 0.6 to about 2.9% of dietary DM. Milk urea nitrogen (MUN) decreased at MCT and HCT levels of supplementation (P < 0.01) but milk fat, CP and lactose percentage were not affected by CT supplementation. The CT supplementation increased N concentration in faeces for LCT and MCT treatments (P < 0.05), suggesting partitioning of dietary N away from urine. When CT was pelleted with grain, in a second experiment and fed twice daily as a supplement at milking, it reduced the acceptability relative to pellets without CT, and tended to lower milk production from 25.4 to 24.5 kg/day, although the decline was not significant (P > 0.05). The diet of cows fed pellets with CT contained about 1.2% CT in the DM but neither milk constituents nor MUN were affected by CT-supplemented grain (P > 0.05). These findings demonstrate

  18. Effects of selected endophyte and tall fescue cultivar combinations on steer grazing performance, indicators of fescue toxicosis, feedlot performance, and carcass traits.

    PubMed

    Parish, J A; Parish, J R; Best, T F; Boland, H T; Young, C A

    2013-01-01

    Five tall fescue [Lolium arundinaceum (Schreb.)] pastures [wild-type 'Kentucky-31' with 78.0% of plants infected with ergot alkaloid-producing endophyte Neotyphodium coenophialum (KY31 E+), 'Jesup' AR542 endophyte-infected contaminated with 30.3% tall fescue containing ergot alkaloid producing-endophyte (Jesup AR542 E+); 'GA-186' AR584 endophyte-infected contaminated with 11.8% tall fescue containing ergot alkaloid producing-endophyte (AGRFA 140); 'PDF' AR584 endophyte-infected contaminated with 5.5% tall fescue containing ergot alkaloid producing-endophyte (AGRFA 144); and 'KYFA 9301' AR584 endophyte-infected contaminated with 10.0% tall fescue containing ergot alkaloid producing-endophyte (AGRFA 150)] were compared for steer growth performance, toxicity, feedlot performance, and carcass traits. Steers (mean initial BW=322 kg) grazed pastures for 84 d in spring and 56 d in autumn for 2 yr. Steers were shipped after grazing in Prairie, MS, to Macedonia, IA, for finishing. Mean herbage mass was not different (P=0.15) among pastures. Posttreatment (d 28+) serum prolactin concentrations were depressed (P=0.013) on KY31 E+. Steers grazing KY31 E+ had greater (P<0.01) posttreatment rectal temperatures during spring. Spring hair coat scores were greatest (P<0.01) on KY31 E+ at d 56 and 84. Steer ADG was least (P<0.01) on KY31 E+ in spring and depressed (P=0.014) on KY31 E+ and Jesup AR542 E+ in autumn. Spring grazing ADG was greater (P=0.049) on AGRFA 150 than Jesup AR542 E+ and AGRFA 140. No BW differences (P=0.09) among pastures were seen at reimplant during feedlot finishing. Pasture had no effect on ADG after reimplant (P=0.68), days on feed (P=0.56), or final BW (P=0.55). Exposure to fescue toxicosis did not affect (P≥0.19) carcass traits. Hair coat price discounts applied for spring-grazed steers on KY-31 E+ affected (P<0.01) initial steer monetary values. There were no pasture differences for finishing costs (P≥0.61) or final carcass value (P=0.59). Elite tall

  19. Confirmation of co-denitrification in grazed grassland.

    PubMed

    Selbie, Diana R; Lanigan, Gary J; Laughlin, Ronald J; Di, Hong J; Moir, James L; Cameron, Keith C; Clough, Tim J; Watson, Catherine J; Grant, James; Somers, Cathal; Richards, Karl G

    2015-11-30

    Pasture-based livestock systems are often associated with losses of reactive forms of nitrogen (N) to the environment. Research has focused on losses to air and water due to the health, economic and environmental impacts of reactive N. Di-nitrogen (N2) emissions are still poorly characterized, both in terms of the processes involved and their magnitude, due to financial and methodological constraints. Relatively few studies have focused on quantifying N2 losses in vivo and fewer still have examined the relative contribution of the different N2 emission processes, particularly in grazed pastures. We used a combination of a high (15)N isotopic enrichment of applied N with a high precision of determination of (15)N isotopic enrichment by isotope-ratio mass spectrometry to measure N2 emissions in the field. We report that 55.8 g N m(-2) (95%, CI 38 to 77 g m(-2)) was emitted as N2 by the process of co-denitrification in pastoral soils over 123 days following urine deposition (100 g N m(-2)), compared to only 1.1 g N m(-2) (0.4 to 2.8 g m(-2)) from denitrification. This study provides strong evidence for co-denitrification as a major N2 production pathway, which has significant implications for understanding the N budgets of pastoral ecosystems.

  20. Confirmation of co-denitrification in grazed grassland

    NASA Astrophysics Data System (ADS)

    Selbie, Diana R.; Lanigan, Gary J.; Laughlin, Ronald J.; di, Hong J.; Moir, James L.; Cameron, Keith C.; Clough, Tim J.; Watson, Catherine J.; Grant, James; Somers, Cathal; Richards, Karl G.

    2015-11-01

    Pasture-based livestock systems are often associated with losses of reactive forms of nitrogen (N) to the environment. Research has focused on losses to air and water due to the health, economic and environmental impacts of reactive N. Di-nitrogen (N2) emissions are still poorly characterized, both in terms of the processes involved and their magnitude, due to financial and methodological constraints. Relatively few studies have focused on quantifying N2 losses in vivo and fewer still have examined the relative contribution of the different N2 emission processes, particularly in grazed pastures. We used a combination of a high 15N isotopic enrichment of applied N with a high precision of determination of 15N isotopic enrichment by isotope-ratio mass spectrometry to measure N2 emissions in the field. We report that 55.8 g N m-2 (95%, CI 38 to 77 g m-2) was emitted as N2 by the process of co-denitrification in pastoral soils over 123 days following urine deposition (100 g N m-2), compared to only 1.1 g N m-2 (0.4 to 2.8 g m-2) from denitrification. This study provides strong evidence for co-denitrification as a major N2 production pathway, which has significant implications for understanding the N budgets of pastoral ecosystems.

  1. Confirmation of co-denitrification in grazed grassland

    PubMed Central

    Selbie, Diana R.; Lanigan, Gary J.; Laughlin, Ronald J.; Di, Hong J.; Moir, James L.; Cameron, Keith C.; Clough, Tim J.; Watson, Catherine J.; Grant, James; Somers, Cathal; Richards, Karl G.

    2015-01-01

    Pasture-based livestock systems are often associated with losses of reactive forms of nitrogen (N) to the environment. Research has focused on losses to air and water due to the health, economic and environmental impacts of reactive N. Di-nitrogen (N2) emissions are still poorly characterized, both in terms of the processes involved and their magnitude, due to financial and methodological constraints. Relatively few studies have focused on quantifying N2 losses in vivo and fewer still have examined the relative contribution of the different N2 emission processes, particularly in grazed pastures. We used a combination of a high 15N isotopic enrichment of applied N with a high precision of determination of 15N isotopic enrichment by isotope-ratio mass spectrometry to measure N2 emissions in the field. We report that 55.8 g N m−2 (95%, CI 38 to 77 g m−2) was emitted as N2 by the process of co-denitrification in pastoral soils over 123 days following urine deposition (100 g N m−2), compared to only 1.1 g N m−2 (0.4 to 2.8 g m−2) from denitrification. This study provides strong evidence for co-denitrification as a major N2 production pathway, which has significant implications for understanding the N budgets of pastoral ecosystems. PMID:26615911

  2. Invited review: An evaluation of the likely effects of individualized feeding of concentrate supplements to pasture-based dairy cows.

    PubMed

    Hills, J L; Wales, W J; Dunshea, F R; Garcia, S C; Roche, J R

    2015-03-01

    In pasture-based dairy systems, supplementary feeds are used to increase dry matter intake and milk production. Historically, supplementation involved the provision of the same amount of feed (usually a grain-based concentrate feed) to each cow in the herd during milking (i.e., flat-rate feeding). The increasing availability of computerized feeding and milk monitoring technology in milking parlors, however, has led to increased interest in the potential benefits of feeding individual cows (i.e., individualized or differential feeding) different amounts and types of supplements according to one or more parameters (e.g., breeding value for milk yield, current milk yield, days in milk, body condition score, reproduction status, parity). In this review, we consider the likely benefits of individualized supplementary feeding strategies for pasture-based dairy cows fed supplements in the bail during milking. A unique feature of our review compared with earlier publications is the focus on individualized feeding strategies under practical grazing management. Previous reviews focused primarily on research undertaken in situations where cows were offered ad libitum forage, whereas we consider the likely benefits of individualized supplementary feeding strategies under rotational grazing management, wherein pasture is often restricted to all or part of a herd. The review provides compelling evidence that between-cow differences in response to concentrate supplements support the concept of individualized supplementary feeding. PMID:25582585

  3. Effect of time at pasture and herbage intake on profile of volatile organic compounds of dairy cow milk.

    PubMed

    Ueda, Yasuko; Asakuma, Sadaki; Miyaji, Makoto; Akiyama, Fumiaki

    2016-01-01

    Volatile organic compounds (VOCs) in milk were investigated as quantitative markers of herbage intake (HI) at pasture. Eight Holstein cows were fed indoors with concentrate and conserved forages (grass silage, corn silage and hay) (NG), then were divided into three treatments according to the duration of access to pasture: 4 h (G4), 8 h (G8), and 20 h (G20) per day. The HIs were 4.3, 8.6, and 13.0 kg dry matter/day for the G4, G8 and G20 treatments, respectively. Milk from cows was sampled and analyzed VOCs by the steam distillation-extraction method and gas chromatography-mass spectrometry (GC-MS). From the intensity of the GC peak area, the levels of 1-phytene (3,7,11,15-tetramethyl-1-hexadecene) and 2-phytene (3,7,11,15-tetramethyl-2-hexadecene) were lowest in NG treatment and markedly increased with grazing time at pasture. With simple regression analysis on the HI to each diterpenoid, a strong correlation was found between the intensity of 1-phytene in the milk and the HI (r = 0.807, P < 0.001). 1-phytene content in milk could be useful as a quantitative marker of the HI of grazing cows. PMID:26032306

  4. Effect of time at pasture and herbage intake on profile of volatile organic compounds of dairy cow milk.

    PubMed

    Ueda, Yasuko; Asakuma, Sadaki; Miyaji, Makoto; Akiyama, Fumiaki

    2016-01-01

    Volatile organic compounds (VOCs) in milk were investigated as quantitative markers of herbage intake (HI) at pasture. Eight Holstein cows were fed indoors with concentrate and conserved forages (grass silage, corn silage and hay) (NG), then were divided into three treatments according to the duration of access to pasture: 4 h (G4), 8 h (G8), and 20 h (G20) per day. The HIs were 4.3, 8.6, and 13.0 kg dry matter/day for the G4, G8 and G20 treatments, respectively. Milk from cows was sampled and analyzed VOCs by the steam distillation-extraction method and gas chromatography-mass spectrometry (GC-MS). From the intensity of the GC peak area, the levels of 1-phytene (3,7,11,15-tetramethyl-1-hexadecene) and 2-phytene (3,7,11,15-tetramethyl-2-hexadecene) were lowest in NG treatment and markedly increased with grazing time at pasture. With simple regression analysis on the HI to each diterpenoid, a strong correlation was found between the intensity of 1-phytene in the milk and the HI (r = 0.807, P < 0.001). 1-phytene content in milk could be useful as a quantitative marker of the HI of grazing cows.

  5. Pasture Characteristics in Three Different Ecotypes at Khovd Aimag, Western Mongolia

    PubMed Central

    Beher, Jutta

    2014-01-01

    The transition of nomadic pastoralism to more sessile forms of rangeland utilization and increased stocking rates can result in the degradation of pasture. After political changes in the 1990s in Mongolia, population growth and missing alternative livelihoods intensified the grazing pressure on pastures, and further decreased the condition of the fragile arid ecosystems. To learn more about the productivity and quality of pasture land in Khovd Aimag in the western region of Mongolia, standing biomass was measured in the alpine region, mountain steppe and semi-desert. Plant samples were analyzed for nitrogen and fiber contents by wet chemistry and Near Infrared Spectroscopy (NIRS). Results show clear differences in distribution of biomass with reduced biomass in the vicinity of temporary settlements. From July to early September plant nitrogen contents decreased in the alpine region, remained unchanged in the mountain steppe and increased in the semi-desert. Nitrogen concentrations were elevated in vegetation close to temporary settlements. For fiber contents (ADF) no clear patterns were found. Neither biomass/m2 nor vegetation cover were appropriate indicators for food quality. PMID:25058023

  6. Sorption, Leaching, and Surface Runoff of Beef Cattle Veterinary Pharmaceuticals under Simulated Irrigated Pasture Conditions

    PubMed Central

    Popova, Inna E.; Bair, Daniel A.; Tate, Kenneth W.; Parikh, Sanjai J.

    2014-01-01

    The use of veterinary pharmaceuticals in beef cattle has led to concerns associated with the development of antibiotic resistance in bacteria and endocrine disruption in aquatic organisms. Despite the potential negative consequences, data on the transport and mitigation of pharmaceuticals in grazed watersheds with irrigated pasture are scarce. The objective of this study was to assess the transport of common beef cattle pharmaceuticals (i.e., oxytetracycline, chlortetracycline, ivermectin) via surface runoff and leachate from manure amended to grass-vegetated soil boxes under irrigated pasture conditions. The transport of pharmaceuticals from animal manure in surface runoff and soil leachate was relatively low and appears to be limited by desorption and transport of pharmaceuticals entrained in the manure. In surface runoff, less than 4.2% of applied pharmaceuticals in manure (initial concentration: 0.2 mg kg−1 of manure) were detected after three weeks of irrigation. Concentrations of pharmaceuticals in surface runoff and leachate never exceeded 0.5 µg L−1. The major portion of pharmaceuticals (up to 99%) was retained in the manure or in the soil directly beneath the manure application site. Based on the minimal transport of oxytetracycline, chlortetracycline, and ivermectin, the risk of significant transport for these targeted beef cattle pharmaceuticals to surface water and groundwater from manure on irrigated pasture appears to be relatively low. PMID:24216368

  7. Grazing management and ecosystem health

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Herbivore activity interacts with weather and vegetation to markedly affect soil condition, biotic activity, and nutrient cycling in pasture and range. In turn, soil condition regulates the impact of environment on nutrient cycling, vegetation, herd or flock management, and animal productivity. Ther...

  8. Multi-decadal impacts of grazing on soil physical and biogeochemical properties in southeast Utah

    USGS Publications Warehouse

    Neff, J.C.; Reynolds, R.L.; Belnap, J.; Lamothe, P.

    2005-01-01

    Many soils in southeastern Utah are protected from surface disturbance by biological soil crusts that stabilize soils and reduce erosion by wind and water. When these crusts are disturbed by land use, soils become susceptible to erosion. In this study, we compare a never-grazed grassland in Canyonlands National Park with two historically grazed sites with similar geologic, geomorphic, and geochemical characteristics that were grazed from the late 1800s until 1974. We show that, despite almost 30 years without livestock grazing, surface soils in the historically grazed sites have 38-43% less silt, as well as 14-51% less total elemental soil Mg, Na, P, and Mn content relative to soils never exposed to livestock disturbances. Using magnetic measurement of soil magnetite content (a proxy for the stabilization of far-traveled eolian dust) we suggest that the differences in Mg, Na, P, and Mn are related to wind erosion of soil fine particles after the historical disturbance by livestock grazing. Historical grazing may also lead to changes in soil organic matter content including declines of 60-70% in surface soil C and N relative to the never-grazed sites. Collectively, the differences in soil C and N content and the evidence for substantial rock-derived nutrient loss to wind erosion implies that livestock grazing could have long-lasting effects on the soil fertility of native grasslands in this part of southeastern Utah. This study suggests that nutrient loss due to wind erosion of soils should be a consideration for management decisions related to the long-term sustainability of grazing operations in arid environments.

  9. Persistence of carotenoid pigments in the blood of concentrate-finished grazing sheep: its significance for the traceability of grass-feeding.

    PubMed

    Prache, S; Priolo, A; Grolier, P

    2003-02-01

    Carotenoid pigments are good biomarkers of grass feeding in sheep. However, grazing lambs are often stall-finished because of grass shortage. We investigated the nature of the carotenoids present in sheep blood and their persistence in this tissue. Four treatments were compared: 1) feeding a concentrate-based diet (n = 10 lambs), 2) grazing followed by a long stall-finishing period (n = 10), 3) grazing followed by a short stall-finishing period (n = 10), and 4) grazing to slaughter weight (n = 10). The concentrate supply was regulated to have similar average daily gain for all treatments. The 40 lambs were allocated to either the grazing or the stall treatments on the basis of their birth date, birth weight, and body weight. The 30 grazing lambs were further allocated to long-stall, short-stall, or grass treatment on the basis of their body weight and plasma carotenoid content. Plasma content of total carotenoids was measured by spectrophotometry during the grazing and the stall periods for all lambs and at slaughter weight for the eight heaviest lambs of each treatment. Analysis of the nature and the concentration of individual carotenoids was performed by HPLC on pasture and stall diets and on blood of grazing lambs. The carotenoid content of the stall diet was 2 to 3% that of the pasture diet. Lutein, zeaxanthin, and beta-carotene accounted for 43 to 58%, 3 to 17%, and 0 to 7% of total plasma carotenoids in grazing lambs, respectively. Two unknown polar carotenoids, expressed in lutein equivalent, accounted for 10 to 22% and 0 to 9% of total carotenoids. Plasma carotenoid content during the grazing and the finishing periods varied among animals (P < 0.001). At slaughter weight, plasma carotenoid content was higher for grass-fed than for stall-fed, long-stall finished, or short-stall finished lambs (P < 0.001), and reliably distinguished grass-fed lambs from all the others. Plasma carotenoid content decreased exponentially with the interval from starting on the

  10. Fertilizer trends

    SciTech Connect

    Donaldson, R.

    1992-01-01

    This fourteenth edition of Fertilizer Trends presents historical fertilizer market data to aid industry, government, and financial market analysis and planners in their study of fertilizer and agricultural market cycles, market planning, and investment decisions. A 27-year summary of the US fertilizer market is presented in graphic and tabular form. Production, use, and trade data are included for each plant nutrient and sulfur. Canadian statistics have been included because of the important role of the Canadian fertilizer industry in the US fertilizer market. World production and consumption of nitrogen, phosphate, and potash are included because of the strong influence of world markets on the domestic market. Planted acreage and plant nutrient application rates for the major crops have been included to illustrate their effect on fertilizer use. Retail prices of the leading US fertilizer materials also are given.

  11. Fertilizer trends

    SciTech Connect

    Donaldson, R.

    1992-12-31

    This fourteenth edition of Fertilizer Trends presents historical fertilizer market data to aid industry, government, and financial market analysis and planners in their study of fertilizer and agricultural market cycles, market planning, and investment decisions. A 27-year summary of the US fertilizer market is presented in graphic and tabular form. Production, use, and trade data are included for each plant nutrient and sulfur. Canadian statistics have been included because of the important role of the Canadian fertilizer industry in the US fertilizer market. World production and consumption of nitrogen, phosphate, and potash are included because of the strong influence of world markets on the domestic market. Planted acreage and plant nutrient application rates for the major crops have been included to illustrate their effect on fertilizer use. Retail prices of the leading US fertilizer materials also are given.

  12. Whole Farm Net Greenhouse Gas Abatement from Establishing Kikuyu-Based Perennial Pastures in South-Western Australia.

    PubMed

    Thomas, Dean T; Sanderman, Jonathan; Eady, Sandra J; Masters, David G; Sanford, Paul

    2012-08-03

    On-farm activities that reduce GHG emissions or sequester carbon from the atmosphere to compensate for anthropogenic emissions are currently being evaluated by the Australian Government as carbon offset opportunities. The aim of this study was to examine the implications of establishing and grazing Kikuyu pastures, integrated as part of a mixed Merino sheep and cropping system, as a carbon offset mechanism. For the assessment of changes in net greenhouse gas emissions, results from a combination of whole farm economic and livestock models were used (MIDAS and GrassGro). Net GHG emissions were determined by deducting increased emissions from introducing this practice change (increased methane and nitrous oxide emissions due to higher stocking rates) from the soil carbon sequestered from growing the Kikuyu pasture. Our results indicate that livestock systems using perennial pastures may have substantially lower net GHG emissions, and reduced GHG intensity of production, compared with annual plant-based production systems. Soil carbon accumulation by converting 45% of arable land within a farm enterprise to Kikuyu-based pasture was determined to be 0.80 t CO₂-e farm ha(-1) yr(-1) and increased GHG emissions (leakage) was 0.19 t CO₂-e farm ha(-1) yr(-1). The net benefit of this practice change was 0.61 t CO₂-e farm ha(-1) yr(-1) while the rate of soil carbon accumulation remains constant. The use of perennial pastures improved the efficiency of animal production almost eight fold when expressed as carbon dioxide equivalent emissions per unit of animal product. The strategy of using perennial pasture to improve production levels and store additional carbon in the soil demonstrates how livestock should be considered in farming systems as both sources and sinks for GHG abatement.

  13. Conversion from forests to pastures in the Colombian Amazon leads to differences in dead wood dynamics depending on land management practices.

    PubMed

    Navarrete, Diego; Sitch, Stephen; Aragão, Luiz E O C; Pedroni, Lucio; Duque, Alvaro

    2016-04-15

    Dead wood, composed of coarse standing and fallen woody debris (CWD), is an important carbon (C) pool in tropical forests and its accounting is needed to reduce uncertainties within the strategies to mitigate climate change by reducing deforestation and forest degradation (REDD+). To date, information on CWD stocks in tropical forests is scarce and effects of land-cover conversion and land management practices on CWD dynamics remain largely unexplored. Here we present estimates on CWD stocks in primary forests in the Colombian Amazon and their dynamics along 20 years of forest-to-pasture conversion in two sub-regions with different management practices during pasture establishment: high-grazing intensity (HG) and low-grazing intensity (LG) sub-regions. Two 20-year-old chronosequences describing the forest-to-pasture conversion were identified in both sub-regions. The line-intersect and the plot-based methods were used to estimate fallen and standing CWD stocks, respectively. Total necromass in primary forests was similar between both sub-regions (35.6 ± 5.8 Mg ha(-1) in HG and 37.0 ± 7.4 Mg ha(-1) in LG). An increase of ∼124% in CWD stocks followed by a reduction to values close to those at the intact forests were registered after slash-and-burn practice was implemented in both sub-regions during the first two years of forest-to-pasture conversion. Implementation of machinery after using fire in HG pastures led to a reduction of 82% in CWD stocks during the second and fifth years of pasture establishment, compared to a decrease of 41% during the same period in LG where mechanization is not implemented. Finally, average necromass 20 years after forest-to-pasture conversion decreased to 3.5 ± 1.4 Mg ha(-1) in HG and 9.3 ± 3.5 Mg ha(-1) in LG, representing a total reduction of between 90% and 75% in each sub-region, respectively. These results highlight the importance of low-grazing intensity management practices during ranching activities in the Colombian

  14. Conversion from forests to pastures in the Colombian Amazon leads to differences in dead wood dynamics depending on land management practices.

    PubMed

    Navarrete, Diego; Sitch, Stephen; Aragão, Luiz E O C; Pedroni, Lucio; Duque, Alvaro

    2016-04-15

    Dead wood, composed of coarse standing and fallen woody debris (CWD), is an important carbon (C) pool in tropical forests and its accounting is needed to reduce uncertainties within the strategies to mitigate climate change by reducing deforestation and forest degradation (REDD+). To date, information on CWD stocks in tropical forests is scarce and effects of land-cover conversion and land management practices on CWD dynamics remain largely unexplored. Here we present estimates on CWD stocks in primary forests in the Colombian Amazon and their dynamics along 20 years of forest-to-pasture conversion in two sub-regions with different management practices during pasture establishment: high-grazing intensity (HG) and low-grazing intensity (LG) sub-regions. Two 20-year-old chronosequences describing the forest-to-pasture conversion were identified in both sub-regions. The line-intersect and the plot-based methods were used to estimate fallen and standing CWD stocks, respectively. Total necromass in primary forests was similar between both sub-regions (35.6 ± 5.8 Mg ha(-1) in HG and 37.0 ± 7.4 Mg ha(-1) in LG). An increase of ∼124% in CWD stocks followed by a reduction to values close to those at the intact forests were registered after slash-and-burn practice was implemented in both sub-regions during the first two years of forest-to-pasture conversion. Implementation of machinery after using fire in HG pastures led to a reduction of 82% in CWD stocks during the second and fifth years of pasture establishment, compared to a decrease of 41% during the same period in LG where mechanization is not implemented. Finally, average necromass 20 years after forest-to-pasture conversion decreased to 3.5 ± 1.4 Mg ha(-1) in HG and 9.3 ± 3.5 Mg ha(-1) in LG, representing a total reduction of between 90% and 75% in each sub-region, respectively. These results highlight the importance of low-grazing intensity management practices during ranching activities in the Colombian

  15. Velocity of Rocky Mountain elk (Cervus elaphus nelsonii) grazing a Northeast Oregon pasture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The use of global positioning systems (GPS) collars is becoming routine in scientific studies of animal activities on landscapes. Typically ecologists are interested in ecological site use, critical habitat, dispersal, and potential environmental impacts of overuse on rangelands and forests. GPS r...

  16. Stream bank erosion in grazed pasture stream reaches of southern Iowa, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stream bank erosion in agricultural landscapes is a major pathway for non-point source sediment and phosphorus loading of receiving waters. The objective of this study was to assess the relationship between the numbers of high stream stage events, as they directly reflect higher erosive stream flow,...

  17. Reading Youth Writing: Grazing in the Pastures of Cultural Studies and Education

    ERIC Educational Resources Information Center

    Hoechsmann, Michael

    2004-01-01

    Reading youth writing is an avenue for the youth where they can express their opinions and ideas. In this article, the author questions whether practitioners in the field of cultural studies are actually engaged in this particular dialogue. The author has examined several articles written by young people from "Toronto Star." He realized that while…

  18. Influence of different systems for feeding supplements to grazing dairy cows on milk fatty acid composition.

    PubMed

    Akbaridoust, Ghazal; Plozza, Tim; Trenerry, Victor C; Wales, William J; Auldist, Martin J; Dunshea, Frank R; Ajlouni, Said

    2014-05-01

    This study investigated the effects of different strategies for feeding supplements to grazing dairy cows on the proportions of fatty acids in milk. Two hundred and sixteen cows were fed supplementary grain and forage according to one of 3 different strategies; (1) CONTROL: cows grazed perennial ryegrass pasture (14 kg dry matter/d) supplemented with milled barley grain fed in the milking parlour and pasture silage offered in the paddock; (2) Partial mixed ration 1 (PMR1): same pasture allotment and supplement as CONTROL strategy, but the supplements presented as a mixed ration after each milking in feedpad, and; (3) Partial mixed ration 2 (PMR2): same pasture allotment, supplemented with a mixed ration of milled barley grain, alfalfa hay, corn silage and crushed corn grain fed in a feedpad. Within each strategy, cows were assigned to receive either 6, 8, 10 or 12 kg dry matter supplement/cow per d. Milk fatty acid proportions from cows fed CONTROL and PMR1 strategies were similar and different from those fed PMR2, particularly at 10 to 12 kg dry matter supplement/cow per d. The reduction in milk fat yield and concentration in cows fed high amounts of supplement as CONTROL and PMR1 was coincident with 4 × increase in 10t-18:1 proportion. The composition of the partial mixed ration (PMR) and the amount offered affected milk fatty acid proportions and milk fat content, however, the method of supplementation did not.

  19. Effect of copper supplementation on the copper status of pasture-fed young Thoroughbreds.

    PubMed

    Pearce, S G; Grace, N D; Firth, E C; Wichtel, J J; Holle, S A; Fennessy, P F

    1998-05-01

    The effect of copper supplementation of pasture fed mares and foals on the copper status of the foals, in terms of plasma, soft tissue and bone copper concentrations and caeruloplasmin activity, was investigated. Twenty-one Thoroughbred foals from either control mares (n = 9), or copper-supplemented mares (n = 12) were divided randomly into control (pasture only, n = 10) or supplemented (pasture and oral copper sulphate, n = 11) groups. The pasture diet was grazed by all animals, and contained 4.4-8.6 mg Cu/kg dry matter (DM). The copper supplement for the mares contained copper sulphate equivalent to 0.5 mg Cu/kg liveweight (LW)/day. This daily dose was converted to allow administration as a thrice weekly dose (i.e. multiplied by 7/3) which was given for 13-25 weeks prior to foaling. The supplemented foals, also dosed 3 times a week, received 0.2 mg Cu/kg LW/day at age 21 days, which was increased to 0.5 mg Cu/kg LW/day at 49 days and was continued at this level until euthanasia at 150 days. Foal plasma copper concentration and caeruloplasmin activity increased from birth to 21 days post partum and then plateaued at a concentration similar to the mare, but the rise in these indices was not affected by copper supplementation of the mare or foal. Copper supplementation of the foal increased foal liver copper concentration at 150 days (P<0.03). Copper intake of diets containing approximately 8-28 mg Cu/kg DM is well reflected by liver copper concentration, but is poorly reflected by bone, other soft tissue copper concentrations and circulating copper status indices.

  20. Testing functional trait-based mechanisms underpinning plant responses to grazing and linkages to ecosystem functioning in grasslands

    NASA Astrophysics Data System (ADS)

    Zheng, S. X.; Li, W. H.; Lan, Z. C.; Ren, H. Y.; Wang, K. B.; Bai, Y. F.

    2014-09-01

    Abundant evidence has shown that grazing alters plant functional traits, ecological strategies, community structure, and ecosystem functioning of grasslands. Few studies, however, have examined how plant responses to grazing are mediated by resource availability and functional group identity. We test functional trait-based mechanisms underlying the responses of different life forms to grazing and linkages to ecosystem functioning along a soil moisture gradient in the Inner Mongolia grassland. A principal component analysis (PCA) based on 9 traits × 276 species matrix showed that the plant size spectrum (i.e., individual biomass), leaf economics spectrum (leaf N content and leaf density), and light competition spectrum (height and stem-leaf biomass ratio) distinguished plant species responses to grazing. The three life forms exhibited differential strategies as indicated by trait responses to grazing. The annuals and biennials adopted grazing-tolerant strategies associated with high growth rate, reflected by high leaf N content and specific leaf area. The perennial grasses exhibited grazing-tolerant strategies associated with great regrowth capacity and high palatability scores, whereas perennial forbs showed grazing-avoidant strategies with short stature and low palatability scores. In addition, the dominant perennial bunchgrasses exhibited mixed tolerance-resistance strategies to grazing and mixed acquisitive-conservative strategies in resource utilization. Grazing increased the relative abundance of perennial forbs with low palatability in the wet and fertile meadow, but it promoted perennial grasses with high palatability in the dry and infertile typical steppe. Our findings suggest that the effects of grazing on plant functional traits are dependent on both the abiotic (e.g., soil moisture) and biotic (e.g., plant functional group identity and composition) factors. Grazing-induced shifts in functional group composition are largely dependent on resource

  1. Characterization and typification of small ruminant farms providing fuelbreak grazing services for wildfire prevention in Andalusia (Spain).

    PubMed

    Mena, Y; Ruiz-Mirazo, J; Ruiz, F A; Castel, J M

    2016-02-15

    Several wildfire prevention programs in Spain are using grazing livestock to maintain fuelbreaks with low levels of biomass. Even though shepherds are remunerated for these services, many of their farms are hardly viable in the current socio-economic context. By analyzing 54 small ruminant farms participating in the Grazed Fuelbreak Network in Andalusia (southern Spain), this research aimed to identify the main types and characteristics of such farms and, considering the challenges they are facing, propose strategies to improve both their economic viability and their effectiveness in fuelbreak grazing. Based on data collected through a survey on key farm management aspects, a multivariate analysis was performed and four main types of farm were identified: two clusters of dairy goat farms and two composed mostly of meat-purpose sheep farms. Farms in all clusters could benefit from improvements in the feeding and reproductive management of livestock, either to enhance their productivity or to make better use of the pasture resources available. Dairy goat farms remain more dependent on external animal feed to ensure a better lactation, therefore they should either diminish their workforce costs per animal or sell transformed products directly to consumers to improve their economic viability. Best fuelbreak grazing results were related to larger flocks combining sheep and goats, lower ratios of fuelbreak surface area per animal, and longer (year-long) grazing periods on fuelbreaks. Therefore, such farm features and adjusted fuelbreak assignments should be favored in wildfire prevention programs using grazing services.

  2. Effect of continuous v. daytime grazing on feed intake and growth of sheep grazing in a semi-arid grassland steppe.

    PubMed

    Müller, K; Lin, L; Wang, C; Glindemann, T; Schiborra, A; Schönbach, P; Wan, H; Dickhoefer, U; Susenbeth, A

    2012-03-01

    In the Inner Mongolian steppe, China, sheep generally graze during daytime and are kept in yards overnight. Hence, nutrients are not returned to the grassland, which might reduce its long-term productivity. Furthermore, the restricted grazing time may limit forage intake and thus the performance of sheep. The aim of this study was therefore to evaluate the impact of continuous 24-h grazing (CG) v. the common daytime grazing (DG) on herbage mass (HM), feed quality, feed organic matter intake (OMI) and live weight gain (LWG) of sheep in the Inner Mongolian steppe. Experiments were carried out from July to September, between 2005 and 2007 on two 2-ha plots per grazing treatment. Each month, the external faecal marker titanium dioxide (TiO(2)) was orally administered to six sheep per plot on 10 consecutive days. Faecal grab samples were obtained from day 6 to 10 and analysed for CP concentrations to estimate digestibility of organic matter (dOM). Faecal TiO(2) concentrations were used to determine the total faecal output and hence OMI of sheep. Concomitant to faeces collection, HM and quality, as well as LWG of the animals were measured. HM and herbage quality did not differ between treatments. However, as the season progressed, concentrations of NDF, ADF and ADL increased, whereas HM and CP concentrations declined. HM and herbage quality parameters differed between years according to the annual precipitation. dOM was similar in CG (0.577) and DG (0.572) sheep, but it decreased from July (0.583) to September (0.558) and differed between years. Accordingly, the OMI of sheep was similar for both treatments across the entire grazing season and all study years. Although mean LWG differed between months and years, it was identical in CG (101.5 g/day) and DG sheep (101.8 g/day). Additional time on pasture during night does not increase feed intake or animal performance. Positive effects of a nutrient reflux on grassland productivity and herbage quality when animals remained

  3. Trees' role in nitrogen leaching after organic, mineral fertilization: a greenhouse experiment.

    PubMed

    López-Díaz, M L; Rolo, V; Moreno, G

    2011-01-01

    New sustainable agriculture techniques are arising in response to the environmental problems caused by intensive agriculture, such as nitrate leaching and surface water eutrophication. Organic fertilization (e.g., with sewage sludge) and agroforestry could be used to reduce nutrient leaching. We assessed the efficiency of establishing trees and pasture species in environmentally sensitive, irrigated Mediterranean grassland soils in controlling nitrate leaching. Four vegetation systems-bare soil, pasture species, cherry trees [ (L.) L.], and pasture-tree mixed plantings-and five fertilization treatments-control, two doses of mineral fertilizer, and two doses of organic fertilizer (sewage sludge)-were tested in a greenhouse experiment over 2 yr. In the experiment, the wet and warm climate characteristics of Mediterranean irrigated croplands and the plant-to-plant and soil-to-plant interactions that occur in open-field agroforestry plantations were simulated. Following a factorial design with six replicates, 120 pots (30-cm radius and 120 cm deep) were filled with a sandy, alluvial soil common in the cultivated fluvial plains of the region. The greatest pasture production and tree growth were obtained with sewage sludge application. Both pasture production and tree growth decreased significantly in the pasture-tree mixed planting. Nitrate leaching was negligible in this latter treatment, except under the highest dose of sewage sludge application. The rapid mineralization of sludge suggested that this organic fertilizer should be used very cautiously in warm, irrigated Mediterranean soils. Mixed planting of pasture species and trees, such as , could be a useful tool for mitigating nitrate leaching from irrigated Mediterranean pastures on sandy soils.

  4. Nutritive value response of forage chicory cultivars to phosphorus fertility

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Forage chicory (Cichorium intybus L.) is a productive plant that appears particularly well suited to improving summer yield of pastures in the USA. Poor palatability of some chicory cultivars in locations with low soil phosphorus fertility has been linked to high levels of sesquiterpene lactones, b...

  5. Yield and persistence response of forage chicory to phosphorus fertility

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Forage chicory (Cichorium intybus) is a productive plant that appears particularly well suited to improving summer yield of pastures in the USA. Poor palatability of some chicory cultivars in locations with low soil phosphorus fertility has been linked to high levels of sesquiterpene lactone, a bit...

  6. 1. South approach to the horse pasture store, looking north; ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. South approach to the horse pasture store, looking north; U.S. Highway 58 (toward Martinsville) is in the foreground - Horsepasture Store, U.S. Route 58 & State Route 687, Horse Pasture, Henry County, VA

  7. 25 CFR 168.5 - Grazing capacity.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Grazing capacity. 168.5 Section 168.5 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GRAZING REGULATIONS FOR THE HOPI PARTITIONED LANDS AREA § 168.5 Grazing capacity. (a) The Area Director shall prescribe the maximum number of each kind of livestock which may be grazed on...

  8. Warming reduces tall fescue abundance but stimulates toxic alkaloid concentrations in transition zone pastures of the U.S.

    PubMed Central

    McCulley, Rebecca L.; Bush, Lowell P.; Carlisle, Anna E.; Ji, Huihua; Nelson, Jim A.

    2014-01-01

    Tall fescue pastures cover extensive acreage in the eastern half of the United States and contribute to important ecosystem services, including the provisioning of forage for grazing livestock. Yet little is known concerning how these pastures will respond to climate change. Tall fescue's ability to persist and provide forage under a warmer and wetter environment, as is predicted for much of this region as a result of climate change, will likely depend on a symbiotic relationship the plant can form with the fungal endophyte, Epichloë coenophiala. While this symbiosis can confer environmental stress tolerance to the plant, the endophyte also produces alkaloids toxic to insects (e.g., lolines) and mammals (ergots; which can cause “fescue toxicosis” in grazing animals). The negative animal health and economic consequences of fescue toxicosis make understanding the response of the tall fescue symbiosis to climate change critical for the region. We experimentally increased temperature (+3°C) and growing season precipitation (+30% of the long-term mean) from 2009–2013 in a mixed species pasture, that included a tall fescue population that was 40% endophyte-infected. Warming reduced the relative abundance of tall fescue within the plant community, and additional precipitation did not ameliorate this effect. Warming did not alter the incidence of endophyte infection within the tall fescue population; however, warming significantly increased concentrations of ergot alkaloids (by 30–40%) in fall-harvested endophyte-infected individuals. Warming alone did not affect loline alkaloid concentrations, but when combined with additional precipitation, levels increased in fall-harvested material. Although future warming may reduce the dominance of tall fescue in eastern U.S. pastures and have limited effect on the incidence of endophyte infection, persisting endophyte-infected tall fescue will have higher concentrations of toxic alkaloids which may exacerbate fescue

  9. Warming reduces tall fescue abundance but stimulates toxic alkaloid concentrations in transition zone pastures of the U.S.

    NASA Astrophysics Data System (ADS)

    Mcculley, Rebecca; Bush, Lowell; Carlisle, Anna; Ji, Huihua; Nelson, Jim

    2014-10-01

    Tall fescue pastures cover extensive acreage in the eastern half of the United States and contribute to important ecosystem services, including the provisioning of forage for grazing livestock. Yet little is known concerning how these pastures will respond to climate change. Tall fescue’s ability to persist and provide forage under a warmer and wetter environment, as is predicted for much of this region as a result of climate change, will likely depend on a symbiotic relationship the plant can form with the fungal endophyte, Epichloë coenophiala. While this symbiosis can confer environmental stress tolerance to the plant, the endophyte also produces alkaloids toxic to insects (e.g., lolines) and mammals (ergots; which can cause ‘fescue toxicosis’ in grazing animals). The negative animal health and economic consequences of fescue toxicosis make understanding the response of the tall fescue symbiosis to climate change critical for the region. We experimentally increased temperature (+3oC) and growing season precipitation (+30% of the long-term mean) from 2009 - 2013 in a mixed species pasture, that included a tall fescue population that was 40% endophyte-infected. Warming reduced the relative abundance of tall fescue within the plant community, and additional precipitation did not ameliorate this effect. Warming did not alter the incidence of endophyte infection within the tall fescue population; however, warming significantly increased concentrations of ergot alkaloids (by 30-40%) in fall-harvested endophyte-infected individuals. Warming alone did not affect loline alkaloid concentrations, but when combined with additional precipitation, levels increased in fall-harvested material. Although future warming may reduce the dominance of tall fescue in eastern U.S. pastures and have limited effect on the incidence of endophyte infection, persisting endophyte-infected tall fescue will have higher concentrations of toxic alkaloids which may exacerbate fescue

  10. Nitrous oxide emissions from in situ deposition of N-labeled ryegrass litter in a pasture soil.

    PubMed

    Pal, Pranoy; Clough, Tim J; Kelliher, Francis M; Sherlock, Robert R

    2013-01-01

    During pasture grazing, freshly harvested herbage (litterfall) is dropped onto soils from the mouths of dairy cattle, potentially inducing nitrous oxide (NO) emissions. Although the Intergovernmental Panel on Climate Change (IPCC) recommends accounting for NO emissions from arable crop residues in national inventories, emissions from the litterfall of grazed pasture systems are not recognized. The objective of this study was to investigate the potential of litterfall to contribute to NO emissions in a field study located on a pasture site in Canterbury, New Zealand (43°38.50' S, 172°27.17' E). We applied N-labeled perennial ryegrass ( L.) to the surface of a pastoral soil (Temuka clay loam) and, for up to 139 d thereafter, quantified the contribution of herbage decomposition to NO production and soil N dynamics. Litterfall contributed to the N enrichment of soil NO-N and NO-N pools. After 49 d, N recovery as NO equated to 0.93% of the surface-applied litter N, with 38 to 75% of the cumulative NO flux occurring within 4 to 10 d of treatment application. Emissions of NO likely resulted from ammonification followed by a coupling of nitrification and denitrification during litter decomposition on the soil surface. The emission factor of the litter deposited in situ was 1.2 ± 0.2%, which is not substantially greater than the IPCC default emission factor value of 1% for crop residues. Further in situ studies using different pasture species and litterfall rates are required to understand the microbial processes responsible for litter-induced NO emissions.

  11. 25 CFR 167.12 - Grazing fees.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Grazing fees. 167.12 Section 167.12 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER NAVAJO GRAZING REGULATIONS § 167.12 Grazing... drought of several years has not broken. The Navajo Tribe therefore requests that the matter...

  12. 25 CFR 167.12 - Grazing fees.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Grazing fees. 167.12 Section 167.12 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER NAVAJO GRAZING REGULATIONS § 167.12 Grazing... drought of several years has not broken. The Navajo Tribe therefore requests that the matter...

  13. 25 CFR 167.12 - Grazing fees.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Grazing fees. 167.12 Section 167.12 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER NAVAJO GRAZING REGULATIONS § 167.12 Grazing... drought of several years has not broken. The Navajo Tribe therefore requests that the matter...

  14. 25 CFR 167.12 - Grazing fees.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Grazing fees. 167.12 Section 167.12 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER NAVAJO GRAZING REGULATIONS § 167.12 Grazing... drought of several years has not broken. The Navajo Tribe therefore requests that the matter...

  15. 25 CFR 173.6 - Stock grazing.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Stock grazing. 173.6 Section 173.6 Indians BUREAU OF... WITHDRAWN OR ACQUIRED IN CONNECTION WITH INDIAN IRRIGATION PROJECTS § 173.6 Stock grazing. Permittees may graze upon lands covered by such permits, such stock as may be required in connection with the...

  16. 25 CFR 700.722 - Grazing associations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 2 2010-04-01 2010-04-01 false Grazing associations. 700.722 Section 700.722 Indians THE... Grazing § 700.722 Grazing associations. (a) The Commissioner may recognize, cooperate with, and assist range unit livestock associations in the management of livestock and range resources. (b)...

  17. 25 CFR 700.722 - Grazing associations.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 2 2011-04-01 2011-04-01 false Grazing associations. 700.722 Section 700.722 Indians THE... Grazing § 700.722 Grazing associations. (a) The Commissioner may recognize, cooperate with, and assist range unit livestock associations in the management of livestock and range resources. (b)...

  18. Effect of Reindeer Grazing on Snowmelt, Albedo and Energy Balance Based on Satellite Data Analysis

    NASA Astrophysics Data System (ADS)

    Cohen, Juval; Pulliainen, Jouni; Ménard, Cécile; Johansen, Bernt; Oksanen, Lauri; Luojus, Kari; Ikonen, Jaakko

    2013-04-01

    Surface albedo has a major influence on the energy balance of the Earth. The albedo difference between snow-covered and snow-free tundra is very significant. Therefore, a delay in the snowmelt will decrease the absorbed solar energy on the ground. Earlier studies have shown that higher and denser vegetation causes earlier snowmelt, and that shrub height and abundance, as well as the total biomass in summer reindeer pastures is lower than in winter pastures. The possibility of using reindeer summer grazing to decrease the vegetation, delay the snowmelt and decrease the ground heating during the snowmelt season is investigated in this study. Satellite data is used to compare between summer and non-summer grazing areas in the northern tundra areas of Fennoscandia. A comparison of vegetation types, NDVI, fractional snow cover and albedo between the Finnish year-round pastures and the Norwegian non-summer pastures is performed. Other factors influencing the snowmelt, such as surface temperature, ground elevation and incoming solar radiation are taken into account. Information about the vegetation on the ground is based on a vegetation map compiled from Landsat TM/ETM+ satellite data and ancillary map information. The NDVI, snowmelt and albedo analyses are performed using multi-temporal remote sensing data such as GlobSnow SE and MODIS based NDVI, snow and albedo products. The results here support previous studies and indicate that vegetation in the summer pastures is shorter and sparser and that the snowmelt there occurs later than in the more densely vegetated, non-summer pastures. More shrubs protruding above the snowpack and earlier snowmelt on the Norwegian side lower the albedo during the snowmelt season. This causes higher solar energy absorption of up to 6 W/m2 in the snowmelt season and yearly contribution of up to 0.5 W/m2 to the yearly energy balance. Therefore this study suggests that summer reindeer herding can be used to delay snowmelt, increase surface

  19. Knowledge and tools to enhance resilience of beef grazing systems for sustainable animal protein production.

    PubMed

    Steiner, Jean L; Engle, David M; Xiao, Xiangming; Saleh, Ali; Tomlinson, Peter; Rice, Charles W; Cole, N Andy; Coleman, Samuel W; Osei, Edward; Basara, Jeffrey; Middendorf, Gerad; Gowda, Prasanna; Todd, Richard; Moffet, Corey; Anandhi, Aavudai; Starks, Patrick J; Ocshner, Tyson; Reuter, Ryan; Devlin, Daniel

    2014-11-01

    Ruminant livestock provides meat and dairy products that sustain health and livelihood for much of the world's population. Grazing lands that support ruminant livestock provide numerous ecosystem services, including provision of food, water, and genetic resources; climate and water regulation; support of soil formation; nutrient cycling; and cultural services. In the U.S. southern Great Plains, beef production on pastures, rangelands, and hay is a major economic activity. The region's climate is characterized by extremes of heat and cold and extremes of drought and flooding. Grazing lands occupy a large portion of the region's land, significantly affecting carbon, nitrogen, and water budgets. To understand vulnerabilities and enhance resilience of beef production, a multi-institutional Coordinated Agricultural Project (CAP), the "grazing CAP," was established. Integrative research and extension spanning biophysical, socioeconomic, and agricultural disciplines address management effects on productivity and environmental footprints of production systems. Knowledge and tools being developed will allow farmers and ranchers to evaluate risks and increase resilience to dynamic conditions. The knowledge and tools developed will also have relevance to grazing lands in semiarid and subhumid regions of the world. PMID:25376887

  20. Knowledge and tools to enhance resilience of beef grazing systems for sustainable animal protein production.

    PubMed

    Steiner, Jean L; Engle, David M; Xiao, Xiangming; Saleh, Ali; Tomlinson, Peter; Rice, Charles W; Cole, N Andy; Coleman, Samuel W; Osei, Edward; Basara, Jeffrey; Middendorf, Gerad; Gowda, Prasanna; Todd, Richard; Moffet, Corey; Anandhi, Aavudai; Starks, Patrick J; Ocshner, Tyson; Reuter, Ryan; Devlin, Daniel

    2014-11-01

    Ruminant livestock provides meat and dairy products that sustain health and livelihood for much of the world's population. Grazing lands that support ruminant livestock provide numerous ecosystem services, including provision of food, water, and genetic resources; climate and water regulation; support of soil formation; nutrient cycling; and cultural services. In the U.S. southern Great Plains, beef production on pastures, rangelands, and hay is a major economic activity. The region's climate is characterized by extremes of heat and cold and extremes of drought and flooding. Grazing lands occupy a large portion of the region's land, significantly affecting carbon, nitrogen, and water budgets. To understand vulnerabilities and enhance resilience of beef production, a multi-institutional Coordinated Agricultural Project (CAP), the "grazing CAP," was established. Integrative research and extension spanning biophysical, socioeconomic, and agricultural disciplines address management effects on productivity and environmental footprints of production systems. Knowledge and tools being developed will allow farmers and ranchers to evaluate risks and increase resilience to dynamic conditions. The knowledge and tools developed will also have relevance to grazing lands in semiarid and subhumid regions of the world.

  1. Recycling biosolids and lake-dredged materials to pasture-based animal agriculture: Alternative nutrient sources for forage productivity and sustainability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Domestic sewage sludge or biosolids and lake-dredged materials are examples of materials that can be used to cut fertilizer costs in pasture-based animal agriculture. Sustainable biosolids and lake-dredged materials management is based upon controlling and influencing the quantity, quality and chara...

  2. New pasture plants intensify invasive species risk.

    PubMed

    Driscoll, Don A; Catford, Jane A; Barney, Jacob N; Hulme, Philip E; Inderjit; Martin, Tara G; Pauchard, Aníbal; Pyšek, Petr; Richardson, David M; Riley, Sophie; Visser, Vernon

    2014-11-18

    Agricultural intensification is critical to meet global food demand, but intensification threatens native species and degrades ecosystems. Sustainable intensification (SI) is heralded as a new approach for enabling growth in agriculture while minimizing environmental impacts. However, the SI literature has overlooked a major environmental risk. Using data from eight countries on six continents, we show that few governments regulate conventionally bred pasture taxa to limit threats to natural areas, even though most agribusinesses promote taxa with substantial weed risk. New pasture taxa (including species, subspecies, varieties, cultivars, and plant-endophyte combinations) are bred with characteristics typical of invasive species and environmental weeds. By introducing novel genetic and endophyte variation, pasture taxa are imbued with additional capacity for invasion and environmental impact. New strategies to prevent future problems are urgently needed. We highlight opportunities for researchers, agribusiness, and consumers to reduce environmental risks associated with new pasture taxa. We also emphasize four main approaches that governments could consider as they build new policies to limit weed risks, including (i) national lists of taxa that are prohibited based on environmental risk; (ii) a weed risk assessment for all new taxa; (iii) a program to rapidly detect and control new taxa that invade natural areas; and (iv) the polluter-pays principle, so that if a taxon becomes an environmental weed, industry pays for its management. There is mounting pressure to increase livestock production. With foresight and planning, growth in agriculture can be achieved sustainably provided that the scope of SI expands to encompass environmental weed risks.

  3. Gastrointestinal nematode infections of first-grazing season calves in Western Europe: general patterns and the effect of chemoprophylaxis.

    PubMed

    Shaw, D J; Vercruysse, J; Claerebout, E; Dorny, P

    1998-02-28

    Research on the prevention of gastrointestinal nematode infections of cattle has mainly concentrated on comparing a specific chemoprophylactic treatment system to an untreated control group on a particular farm. Here, the results from analysis of 85 studies involving over 2000 first grazing season (FGS) calves put onto pasture for at least 4 months from late spring/early summer over a 26-year period in 13 countries in Western Europe are presented. Both control and chemoprophylactic treated FGS calf groups were considered. All chemoprophylactic systems (slow- and pulse-release boli, strategic treatments) were given early in the grazing season. Two general infection levels emerged--'sub-clinical' (32 studies) and 'clinical' (53 studies). The 'sub-clinical' infections were characterised by no clinical symptoms of parasitic gastroenteritis (PGE) being observed in the control groups. Mean faecal egg counts in the 'clinical' control groups were significantly higher than those for 'sub-clinical' control groups for almost the entire season with overall peaks of 275 and 100 EPG respectively. Maximum pasture larval counts were also significantly higher in the 'clinical' control groups with 44% of 'clinical' pastures > 10,000 L3 kg(-1) dry herbage by the end of the FGS, compared to only 15% of 'sub-clinical' pastures. There was a significant positive relationship between log transformed worm burdens from tracers put onto pastures for 2 weeks and the corresponding pasture larval count. No evidence of density dependence in tracer worm burden was observed. Weight gains in the 'clinical' control groups (375 g/day) were significantly lower than those of the 'sub-clinical' control groups (530 g/day). No symptoms of PGE were observed in any of the chemoprophylactic treated groups, but in those studies with an outbreak of PGE in the control group, the treated groups had significantly higher faecal egg and pasture larval counts than treated groups in 'sub-clinical' studies. The

  4. The influence of trees on the thermal environment and behaviour of grazing heifers in Brazilian Midwest.

    PubMed

    Lopes, Luciano Bastos; Eckstein, Camila; Pina, Douglas Santos; Carnevalli, Roberta Aparecida

    2016-04-01

    The intensification of the livestock production system has gained prominence over the last decades. In addition to the reduction of grazing areas and increased productivity per hectare, the intercropping involving forest tree species and ruminants has been established as a sustainable production model, generating income and valuation of natural capital. Besides the social, economic, and environmental aspects, the animal welfare is a noteworthy factor. The objective of this study was to evaluate the microclimatic conditions in an open-pasture and in silvopastoral systems, considering the Temperature Humidity Index (THI) and alterations in animal behavior. Three different pasture arrangements were analyzed in this study: total absence of trees in an open-pasture (ArrA), presence of peripheral trees (Eucalyptus spp.) along the border fences (ArrB), and an intensive wooded area aggregated with pasture (ArrC). A herd of 24 crossbreed heifers (3/4 and 7/8 Holstein-Girolando breed) was evaluated. Behavior data were collected every 15 min starting at 08 h00 with readings ending at 16 h00. THI was used to evaluate the environmental comfort. The THI found in the system with open-pasture and in the two systems with silvopastoral arrangement reached critical levels. The two arrangements with eucalyptus rows were not capable of eliminating heat stress in the conditions found in the north region of Mato Grosso State although better conditions were obtained under the tree canopy. The differences between the microclimatic variables for the three arrangements modified the behavior of the animals regarding their location and activity, except for water consumption. PMID:26894499

  5. Continuous measurement of reticuloruminal pH values in dairy cows during the transition period from barn to pasture feeding using an indwelling wireless data transmitting unit.

    PubMed

    Gasteiner, J; Horn, M; Steinwidder, A

    2015-04-01

    This study was performed to investigate the effect of the transition from barn feeding to pasture on the pattern of reticuloruminal pH values in 8 multiparous dairy cows. A indwelling wireless data transmitting system for pH measurement was given to 8 multiparous cows orally. Reticuloruminal pH values were measured every 600 s over a period of 42 days. After 7 days of barn feeding (period 1), all of the animals were pastured with increasing grazing times from 2 to 7 h/day over 7 days (period 2). From day 15 to day 21 (period 3), the cows spent 7 h/day on pasture. Beginning on day 22, the animals had 20 h/day access to pasture (day and night grazing). To study reticuloruminal adaptation to pasture feeding, the phase of day and night grazing was subdivided into another 3 weekly periods (periods 4-6). Despite a mild transition period from barn feeding to pasture, significant effects on reticuloruminal pH values were observed. During barn feeding, the mean reticuloruminal pH value for all of the cows was 6.44 ± 0.14, and the pH values decreased significantly (p < 0.001) during period 2 and 3 to 6.24 ± 0.17 and 6.21 ± 0.19 respectively. During periods 4, 5 and 6, the reticuloruminal pH values increased again (pH 6.25 ± 0.22; pH 6.31 ± 0.17; pH 6.37 ± 0.16). Our results showed that the animals had significantly lowered reticuloruminal pH during the periods of feed transition from barn to pasture feeding. Despite these significant changes, the decrease was not harmful, as indicated by data of feed intake and milk production.

  6. Carbon, Water Vapor, and Energy Fluxes of Grazed and Ungrazed Tallgrass Prairie

    NASA Astrophysics Data System (ADS)

    Owensby, C. E.; Ham, J. M.; Auen, L. M.

    2004-12-01

    To determine the impact of seasonal steer grazing on annual CO2 fluxes of annually-burned native tallgrass prairie, we used conditional sampling (relaxed eddy accumulation) on adjacent pastures of grazed (GR) and ungrazed (UG) tallgrass prairie from 1998 to 2001 and eddy correlation from 2002 to 2004. Fluxes of CO2 were measured almost continuously (24 hr) from immediately following burning through the burn date the following year (365 d). Aboveground biomass and leaf area were determined by clipping biweekly during the growing season. Carbon lost due to burning was estimated by clipping immediately prior to burning and collecting residual surface carbon after the burn. Soil CO2 flux was measured biweekly at midday each year using portable chambers from 1998 to 2002 and diurnally by large autochambers from 2002 to 2004. Steers were stocked at twice the normal season-long stocking rate (0.81 ha steer-1) for the first half of the grazing season (~May 1 to July 15) and the area left ungrazed the remainder of the year. That system of grazing is termed "intensive early stocking" and is commonly used throughout the Kansas Flint Hills. During the early growing season, grazing reduced net carbon exchange relative to the reduction in green leaf area, but as the growing season progressed on the grazed area, regrowth produced younger leaves that had an apparent higher photosynthetic efficiency. Despite a substantially greater green leaf area on the ungrazed area, greater positive net carbon flux occurred on the grazed area during the late season. Nighttime carbon losses were greater on the ungrazed area in the early season, but were greater on the grazed area late in the season. During the peak growth period, an amount equivalent to ~80% of the carbon fixed on a clear day was lost each day through soil CO2 flux and plant respiration. Soil CO2 flux followed a definite diurnal pattern during the growing season with daytime fluxes twice that of nighttime. During the dormant

  7. Adverse impacts of pasture abandonment in Himalayan protected areas: Testing the efficiency of a Natural Resource Management Plan (NRMP)

    SciTech Connect

    Nautiyal, Sunil . E-mail: sunil.nautiyal@zalf.de; Kaechele, Harald

    2007-03-15

    The high elevational areas in the Himalayas of India are dominated by forests and alpine pastures. There are many protected areas in the region, including Nanda Devi Biosphere Reserve (NDBR) and Valley of Flowers (VOF) where natural resource management plan (NRMP) has been implemented for the conservation of biodiversity. This has affected the traditional animal husbandry system, as well as the vegetation dynamics of alpine pastures. An integrated approach to studying the impact of NRMP in the region has been applied by us. First, a survey was conducted regarding livestock management, data pertaining the livestock husbandry, the role of animal husbandry in economics of rural household, and socioeconomics. Second, field based study on phytosociology of some important alpine herbs was done to enumerate the density and species richness in different land mark of the region. Thereafter, satellite data and Geographic Information System (GIS) were used to develop a land cover map of the area and to note changes in the landscape over time after implementation of NRMP. From an economic point of view the implementation of such plan is a setback to the rural economy. However, the ecological perspective of such models is a threat to the diversity of alpine pastures. The invasion of bushes/thorny bushes/shrubs and weeds with their luxuriant growth is changing the vegetation index and dynamics. Consequently, the diversity of herbs in alpine pastures of the Himalayan Mountains is in jeopardy. Overall, the situation is leading to landscape change in the region. This study is helpful for generating useful outcomes and strategies considering the question or debate 'is grazing good or bad for pasture ecosystems in the Himalayas?'.

  8. Grazing behaviour and dry matter intake of llamas (Lama glama) and German black- head mutton sheep (Ovis orientalis forma aries) under Central European conditions.

    PubMed

    Stölzl, Anna Maria; Lambertz, Christian; Gauly, Matthias

    2015-01-01

    The aim of the present study was to assess the behaviour of llamas (Lama glama) and German blackhead mutton sheep (Ovis orientalis forma aries) when kept under Central European grazing conditions. In total, six adult female sheep and six adult female llamas were observed by direct observation during one week, in which each group was observed for a total time of 24 h. The animals were kept on the same pasture, but the species were raised in separate plots. Forage height before and after the experimental period were determined using a rising plate meter to calculate the average daily dry matter intake (DMI). Llamas had a daily DMI of 0.85%/BW and sheep of 1.04%/BW, respectively. The following behaviours were recorded by direct observation: grazing standing up, grazing lying down, ruminating standing up, ruminating lying down, lying down, lying down lateral and standing. Both species grazed for more than 50% of the time. Ruminating was predominantly performed while standing and lying by sheep (about 50% of the night and 12% of the day) and while lying by llamas (54% of the night and 10% of the day). In conclusion, sheep and llamas differed in grazing behaviour and daily biorhythm. These differences indicate that sheep and llamas may not synchronize their behaviour when co-grazed, though particularly in co-grazing studies the observation period should be extended.

  9. Controlling Fertility.

    ERIC Educational Resources Information Center

    Donnay, France

    1991-01-01

    Recent developments in fertility control are presented in relation to the global demographic situation. Discussion focuses on changes in scientific knowledge and concepts that have shifted the focus from birth control to planned parenthood to the notion of controlled fertility. The place of family planning programs, including their socioeconomic…

  10. Ecology of grazing lawns in Africa.

    PubMed

    Hempson, Gareth P; Archibald, Sally; Bond, William J; Ellis, Roger P; Grant, Cornelia C; Kruger, Fred J; Kruger, Laurence M; Moxley, Courtney; Owen-Smith, Norman; Peel, Mike J S; Smit, Izak P J; Vickers, Karen J

    2015-08-01

    Grazing lawns are a distinct grassland community type, characterised by short-stature and with their persistence and spread promoted by grazing. In Africa, they reveal a long co-evolutionary history of grasses and large mammal grazers. The attractiveness to grazers of a low-biomass sward lies in the relatively high quality of forage, largely due to the low proportion of stem material in the sward; this encourages repeat grazing that concomitantly suppresses tall-grass growth forms that would otherwise outcompete lawn species for light. Regular grazing that prevents shading and maintains sward quality is thus the cornerstone of grazing lawn dynamics. The strong interplay between abiotic conditions and disturbance factors, which are central to grazing lawn existence, can also cause these systems to be highly dynamic. Here we identify differences in growth form among grazing lawn grass species, and assess how compositional differences among lawn types, as well as environmental variables, influence their maintenance requirements (i.e. grazing frequency) and vulnerability to degradation. We also make a clear distinction between the processes of lawn establishment and lawn maintenance. Rainfall, soil nutrient status, grazer community composition and fire regime have strong and interactive influences on both processes. However, factors that concentrate grazing pressure (e.g. nutrient hotspots and sodic sites) have more bearing on where lawns establish. Similarly, we discuss the relevance of enhanced rates of nitrogen cycling and of sodium levels to lawn maintenance. Grazer community composition and density has considerable significance to grazing lawn dynamics; not all grazers are adapted to foraging on short-grass swards, and differences in body size and relative mouth dimensions determine which species are able to convert tall-grass swards into grazing lawns under different conditions. Hence, we evaluate the roles of different grazers in lawn dynamics, as well as the

  11. Ecology of grazing lawns in Africa.

    PubMed

    Hempson, Gareth P; Archibald, Sally; Bond, William J; Ellis, Roger P; Grant, Cornelia C; Kruger, Fred J; Kruger, Laurence M; Moxley, Courtney; Owen-Smith, Norman; Peel, Mike J S; Smit, Izak P J; Vickers, Karen J

    2015-08-01

    Grazing lawns are a distinct grassland community type, characterised by short-stature and with their persistence and spread promoted by grazing. In Africa, they reveal a long co-evolutionary history of grasses and large mammal grazers. The attractiveness to grazers of a low-biomass sward lies in the relatively high quality of forage, largely due to the low proportion of stem material in the sward; this encourages repeat grazing that concomitantly suppresses tall-grass growth forms that would otherwise outcompete lawn species for light. Regular grazing that prevents shading and maintains sward quality is thus the cornerstone of grazing lawn dynamics. The strong interplay between abiotic conditions and disturbance factors, which are central to grazing lawn existence, can also cause these systems to be highly dynamic. Here we identify differences in growth form among grazing lawn grass species, and assess how compositional differences among lawn types, as well as environmental variables, influence their maintenance requirements (i.e. grazing frequency) and vulnerability to degradation. We also make a clear distinction between the processes of lawn establishment and lawn maintenance. Rainfall, soil nutrient status, grazer community composition and fire regime have strong and interactive influences on both processes. However, factors that concentrate grazing pressure (e.g. nutrient hotspots and sodic sites) have more bearing on where lawns establish. Similarly, we discuss the relevance of enhanced rates of nitrogen cycling and of sodium levels to lawn maintenance. Grazer community composition and density has considerable significance to grazing lawn dynamics; not all grazers are adapted to foraging on short-grass swards, and differences in body size and relative mouth dimensions determine which species are able to convert tall-grass swards into grazing lawns under different conditions. Hence, we evaluate the roles of different grazers in lawn dynamics, as well as the

  12. Influence of pre- and post-pubertal grazing regimes on adult testicular morphology in extensively reared corriedale rams.

    PubMed

    Bielli, A; Gastel, M T; Pedrana, G; Moraña, A; Castrillejo, A; Lundeheim, N; Forsberg, M; Rodriguez-Martinez, H

    2000-02-28

    The aim of the present study was to determine whether pre- and post-pubertal young rams on different grazing regimes, resulting in differences in live weight (LW), would show corresponding differences in testicular growth or testicular morphometry that could influence the reproductive traits of these rams upon reaching adulthood. Forty-one spring-born Corriedale rams were reared on either native pasture (low feeding level, Group L, n=22) or improved pasture (higher feeding level, Group H, n=19) from 1 to 7 months of age. Thereafter, half the animals in the native-pasture group were placed on improved pasture and vice versa, thus creating an additional four differential-grazing treatment groups (Groups LL, n=11; LH, n=11; HL, n=10; and HH, n=9). Animals were managed in this way until 18 months of age. Half the animals from each group were then castrated and their testes were subjected to morphometric analysis. The remaining animals (Groups LL, n=6; LH, n=6; HL, n=5; and HH, n=4) were managed together until 30 months of age (from 18 to 27 months on native pastures and from 27 to 30 months of age on improved pastures, at a stocking rate of two to three rams per hectare), whereupon they were also castrated for testicular morphometry. LW and scrotal circumference (SC) were recorded every 60 days. The stereological analysis of testicular parenchyma included counts of elongated spermatids and Sertoli cells. Differences (P<0.001) in LW were observed between feeding levels, even at 30 months of age. Differences (P<0.001) in SC existing at the end of the differential treatment (18 months of age) disappeared (n.s.) soon after. Most differences (P<0.05) in testicular morphometry existing at the end of the differential treatments were no longer significant 1 year later. It is concluded that changes in grazing management during pre- and post-pubertal periods can induce short-lived differences in testicular post-natal growth in Corriedale rams but do not influence testicular

  13. Impact of cattle grazing on soil and vegetation - a case study in a mountainous region of Austria

    NASA Astrophysics Data System (ADS)

    Bohner, Andreas; Foldal, Cecilie; Jandl, Robert

    2015-04-01

    In mountainous regions of Austria and of many other European countries, climate change may cause a further intensification of grassland management. Therefore, the effects of intensive cattle grazing on selected soil chemical and physical properties, above- and below-ground phytomass, forage quality, plant species composition and plant species richness at the scale of a representative paddock in a mountainous region of Austria were investigated. At the study site (Styrian Enns valley; 675 m a.s.l.), climate is relatively cool and humid, with a mean annual air temperature of 6.7°C and a mean annual precipitation of 970 mm, of which 66% falls during the vegetation period (April-October). The soil is a deep, base-rich Cambisol with a loamy sand texture. The paddock investigated has a total area of about 2 ha and had been grazed by dairy cows (Brown Swiss) five times per grazing season. The stocking density was 4 cows ha-1 during 180 days from early May to the end of October with a grazing time of about 8 hours per day. The strip grazed permanent pasture was manured annually for a long time, mostly with cattle slurry. Vegetation surveys were carried out using the method of Braun-Blanquet. Above- and below-ground phytomass, forage quality and mineral element concentration in the harvestable above-ground plant biomass were determined by using standard methods. During the grazing season surface soil samples (0-10 cm depth) for chemical analyses were collected before each grazing period (5 analyses of composite samples per site). At the beginning and the end of the grazing season also soil samples for physical analyses were taken from the topsoil (0-15 cm depth). Heavy cattle treading led to a substantial soil compaction especially in the 5-10 cm layer and to a deterioration of topsoil structure. The porous crumb structure was replaced by a compact platy structure. The topsoil was enriched with nutrients (mainly nitrogen, potassium, phosphorus and boron). The degree of

  14. Phosphorus and Defoliation Interact and Improve the Growth and Composition of the Plant Community and Soil Properties in an Alpine Pasture of Qinghai-Tibet Plateau

    PubMed Central

    Qi, Juan; Nie, Zhongnan; Jiao, Ting; Zhang, Degang

    2015-01-01

    Pasture degradation caused by overgrazing and inappropriate fertiliser management is a major production and environmental threat in Qinghai-Tibet Plateau. Previous research has focused on the effects of mixed nitrogen (N) and phosphorus (P) fertiliser and reduced grazing pressure on the plant community of the grassland; however, the role of P and how it interacts with various defoliation (the process of the complete or partial removal of the above-ground parts of plants by grazing or cutting) intensities on the plant and soil of the grassland ecosystem have not been quantified. A field experiment was conducted to quantify how P application in combination of defoliation pressure could impact the dynamic change of the plant and soil in a native alpine grassland ecosystem of the Qinghai-Tibet Plateau, China, from May 2012 to September 2014. A split-plot design with 4 replicates and repeated measures was used to determine the growth and composition of plant community and soil physical and chemical properties under various levels of P fertiliser and defoliation intensity. The results showed that applying 20 kg P/ha increased the herbage yield of Melissitus ruthenica by 68% and total pasture yield by 25%. Close defoliation favoured the growth and plant frequency of the shorter species, whereas lax defoliation favoured that of the taller plant species. Medium P rate and cutting to 3 cm above ground gave an overall best outcome in pasture yield, quality and frequency and soil moisture and nutrient concentration. Application of P fertiliser with a moderate defoliation pressure to promote legume growth and N fixation has the potential to achieve multiple benefits in increasing pasture and livestock production and improving environmental sustainability in the alpine pasture of Qinghai-Tibet Plateau, a fragile and P-deficient ecosystem zone in China and its western neighbouring countries. PMID:26513363

  15. Phosphorus and Defoliation Interact and Improve the Growth and Composition of the Plant Community and Soil Properties in an Alpine Pasture of Qinghai-Tibet Plateau.

    PubMed

    Qi, Juan; Nie, Zhongnan; Jiao, Ting; Zhang, Degang

    2015-01-01

    Pasture degradation caused by overgrazing and inappropriate fertiliser management is a major production and environmental threat in Qinghai-Tibet Plateau. Previous research has focused on the effects of mixed nitrogen (N) and phosphorus (P) fertiliser and reduced grazing pressure on the plant community of the grassland; however, the role of P and how it interacts with various defoliation (the process of the complete or partial removal of the above-ground parts of plants by grazing or cutting) intensities on the plant and soil of the grassland ecosystem have not been quantified. A field experiment was conducted to quantify how P application in combination of defoliation pressure could impact the dynamic change of the plant and soil in a native alpine grassland ecosystem of the Qinghai-Tibet Plateau, China, from May 2012 to September 2014. A split-plot design with 4 replicates and repeated measures was used to determine the growth and composition of plant community and soil physical and chemical properties under various levels of P fertiliser and defoliation intensity. The results showed that applying 20 kg P/ha increased the herbage yield of Melissitus ruthenica by 68% and total pasture yield by 25%. Close defoliation favoured the growth and plant frequency of the shorter species, whereas lax defoliation favoured that of the taller plant species. Medium P rate and cutting to 3 cm above ground gave an overall best outcome in pasture yield, quality and frequency and soil moisture and nutrient concentration. Application of P fertiliser with a moderate defoliation pressure to promote legume growth and N fixation has the potential to achieve multiple benefits in increasing pasture and livestock production and improving environmental sustainability in the alpine pasture of Qinghai-Tibet Plateau, a fragile and P-deficient ecosystem zone in China and its western neighbouring countries. PMID:26513363

  16. Phosphorus and Defoliation Interact and Improve the Growth and Composition of the Plant Community and Soil Properties in an Alpine Pasture of Qinghai-Tibet Plateau.

    PubMed

    Qi, Juan; Nie, Zhongnan; Jiao, Ting; Zhang, Degang

    2015-01-01

    Pasture degradation caused by overgrazing and inappropriate fertiliser management is a major production and environmental threat in Qinghai-Tibet Plateau. Previous research has focused on the effects of mixed nitrogen (N) and phosphorus (P) fertiliser and reduced grazing pressure on the plant community of the grassland; however, the role of P and how it interacts with various defoliation (the process of the complete or partial removal of the above-ground parts of plants by grazing or cutting) intensities on the plant and soil of the grassland ecosystem have not been quantified. A field experiment was conducted to quantify how P application in combination of defoliation pressure could impact the dynamic change of the plant and soil in a native alpine grassland ecosystem of the Qinghai-Tibet Plateau, China, from May 2012 to September 2014. A split-plot design with 4 replicates and repeated measures was used to determine the growth and composition of plant community and soil physical and chemical properties under various levels of P fertiliser and defoliation intensity. The results showed that applying 20 kg P/ha increased the herbage yield of Melissitus ruthenica by 68% and total pasture yield by 25%. Close defoliation favoured the growth and plant frequency of the shorter species, whereas lax defoliation favoured that of the taller plant species. Medium P rate and cutting to 3 cm above ground gave an overall best outcome in pasture yield, quality and frequency and soil moisture and nutrient concentration. Application of P fertiliser with a moderate defoliation pressure to promote legume growth and N fixation has the potential to achieve multiple benefits in increasing pasture and livestock production and improving environmental sustainability in the alpine pasture of Qinghai-Tibet Plateau, a fragile and P-deficient ecosystem zone in China and its western neighbouring countries.

  17. Methane uptake and emissions in a typical steppe grazing system during the grazing season

    NASA Astrophysics Data System (ADS)

    Wang, Xiaoya; Zhang, Yingjun; Huang, Ding; Li, Zhiqiang; Zhang, Xiaoqing

    2015-03-01

    This study investigated the effects of livestock grazing on CH4 emissions by testing six grazing conditions at Guyuan State Key Monitoring and Research Station of Grassland Ecosystem (China) in 2011 and 2012. Under all grazing systems, steppe soils were measured to be CH4 sinks. The uptake of CH4 by grassland was primarily determined by topsoil (7 cm) temperature and soil (0-7 cm) moisture in grassland at short-term grazing and non-grazing. The cumulative uptake of CH4 during the grazing period for all conditions was 0.88-3.23 kg hm-2 CH4, and the highest level was observed in the continuously moderate grazing condition. Reducing grazing stocking in the short-term did not significantly change the uptake of CH4 when compared with continuously heavy grazing condition. Enteric CH4 emissions were not significantly affected by the grazing period or conditions. The uptake of CH4 by grassland soil offset 3.1-8.6% of the CH4 emissions from the grazing sheep and was most effective at the continuously moderate grazing condition. These findings imply that continuously moderate grazing is the best approach considered here for optimizing the soil as a sink for atmospheric CH4.

  18. New pasture plants intensify invasive species risk

    PubMed Central

    Driscoll, Don A.; Catford, Jane A.; Barney, Jacob N.; Hulme, Philip E.; Inderjit; Martin, Tara G.; Pauchard, Aníbal; Pyšek, Petr; Richardson, David M.; Riley, Sophie; Visser, Vernon

    2014-01-01

    Agricultural intensification is critical to meet global food demand, but intensification threatens native species and degrades ecosystems. Sustainable intensification (SI) is heralded as a new approach for enabling growth in agriculture while minimizing environmental impacts. However, the SI literature has overlooked a major environmental risk. Using data from eight countries on six continents, we show that few governments regulate conventionally bred pasture taxa to limit threats to natural areas, even though most agribusinesses promote taxa with substantial weed risk. New pasture taxa (including species, subspecies, varieties, cultivars, and plant-endophyte combinations) are bred with characteristics typical of invasive species and environmental weeds. By introducing novel genetic and endophyte variation, pasture taxa are imbued with additional capacity for invasion and environmental impact. New strategies to prevent future problems are urgently needed. We highlight opportunities for researchers, agribusiness, and consumers to reduce environmental risks associated with new pasture taxa. We also emphasize four main approaches that governments could consider as they build new policies to limit weed risks, including (i) national lists of taxa that are prohibited based on environmental risk; (ii) a weed risk assessment for all new taxa; (iii) a program to rapidly detect and control new taxa that invade natural areas; and (iv) the polluter-pays principle, so that if a taxon becomes an environmental weed, industry pays for its management. There is mounting pressure to increase livestock production. With foresight and planning, growth in agriculture can be achieved sustainably provided that the scope of SI expands to encompass environmental weed risks. PMID:25368175

  19. New pasture plants intensify invasive species risk.

    PubMed

    Driscoll, Don A; Catford, Jane A; Barney, Jacob N; Hulme, Philip E; Inderjit; Martin, Tara G; Pauchard, Aníbal; Pyšek, Petr; Richardson, David M; Riley, Sophie; Visser, Vernon

    2014-11-18

    Agricultural intensification is critical to meet global food demand, but intensification threatens native species and degrades ecosystems. Sustainable intensification (SI) is heralded as a new approach for enabling growth in agriculture while minimizing environmental impacts. However, the SI literature has overlooked a major environmental risk. Using data from eight countries on six continents, we show that few governments regulate conventionally bred pasture taxa to limit threats to natural areas, even though most agribusinesses promote taxa with substantial weed risk. New pasture taxa (including species, subspecies, varieties, cultivars, and plant-endophyte combinations) are bred with characteristics typical of invasive species and environmental weeds. By introducing novel genetic and endophyte variation, pasture taxa are imbued with additional capacity for invasion and environmental impact. New strategies to prevent future problems are urgently needed. We highlight opportunities for researchers, agribusiness, and consumers to reduce environmental risks associated with new pasture taxa. We also emphasize four main approaches that governments could consider as they build new policies to limit weed risks, including (i) national lists of taxa that are prohibited based on environmental risk; (ii) a weed risk assessment for all new taxa; (iii) a program to rapidly detect and control new taxa that invade natural areas; and (iv) the polluter-pays principle, so that if a taxon becomes an environmental weed, industry pays for its management. There is mounting pressure to increase livestock production. With foresight and planning, growth in agriculture can be achieved sustainably provided that the scope of SI expands to encompass environmental weed risks. PMID:25368175

  20. Defoliation effects on pasture photosynthesis and respiration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ecosystem C gain or loss from managed grasslands can depend on the type and intensity of management practices that are employed. However, limited information is available at the field scale on how the type of defoliation, specifically grazing vs. cutting, affects gross primary productivity (GPP) an...

  1. Fertility of ram semen frozen in Bioexcell and used for cervical artificial insemination.

    PubMed

    Gil, J; Rodriguez-Irazoqui, M; Lundeheim, N; Söderquist, L; Rodríguez-Martínez, H

    2003-03-01

    The current use of ingredients of animal origin, such as egg yolk, in semen extenders presents a risk of microbial contamination, and has led to the search for alternatives. Such an extender is commercially available for bull semen (Bioexcell), IMV, L'Aigle, France), and it has previously been tested in vitro for freezing ram semen, with satisfactory results. The aim of the present study was to compare the fertility results of ewes in Uruguay, after cervical insemination with ram semen that was frozen in Bioexcell versus semen frozen in a conventional milk-egg yolk extender (control). Semen from five Corriedale rams was frozen, using a split sample design, in either milk-egg yolk or Bioexcell extender, using a two-step extension method. The sperm parameters assessed after thawing were subjective motility, membrane integrity (SYBR-14/PI), and capacitation status (CTC). Thawed semen was inseminated intracervically once during spontaneous estrus in 970 Corriedale ewes that grazed in natural pastures, under extensive management conditions. Fertility was recorded as nonreturn rates at 21 days (NRR-21) and 36 days (NRR-36) after artificial insemination (AI), as well as pregnancy rate (PR-US, diagnosed ultrasonographically 50 days after AI of the last ewe). Subjective motility was slightly higher in Bioexcell than in the milk extender (47 vs. 46.5%; NS), as was membrane integrity (38 vs. 37.7%; NS) and the percentage of uncapacitated spermatozoa (28.5 vs. 26.3%; NS). There were no statistically significant differences in fertility rates found between Bioexcell and the control extender: NRR-21 (35.9 vs. 33.2%), NRR-36 (34.8 vs. 32.6%), and PR-US (28.4 vs. 27.2%). In conclusion, Bioexcell appears to be an alternative to the conventional milk-egg yolk extender for freezing ram semen, and provides similar fertility results after cervical AI under extensive management conditions. Thus, Bioexcell, containing no additives of animal origin, can offer a safer alternative when

  2. Long-term Effects of Shrub Encroachment and Grazing on Soil Microbial Composition and Function

    NASA Astrophysics Data System (ADS)

    Gallery, R. E.; O'Shea, C.; Kwiecien, A.; Predick, K.; Archer, S. R.

    2014-12-01

    Drylands account for ca. 35% of terrestrial net primary productivity and thus play a significant role in global water and biogeochemical cycles. Replacement of grasses by shrubs has been widespread in these systems and has altered rates of erosion and native plant biodiversity and productivity. The net effect of these changes on biogeochemical cycling is not well understood. Projected warmer and drier conditions may further alter the function and stability of these ecosystems and soil resources through direct effects on soil microbiota and plant-microbe interactions. We quantified microbial community responses to long-term livestock grazing and shrub encroachment in a Sonoran Desert grassland. We sought to characterize tipping points where biotic controls over ecosystem processes shift from being 'grass-driven' to 'shrub-driven.' We asked: How do livestock grazing (the predominant land use in dryland ecosystems) and shrub invasion (a predominant land cover change) interact to influence microbial biomass and the relative abundance of bacteria, archaea, and fungi and their extracellular enzyme activities? Surface soil from bare-ground patches, native and invasive grass rhizospheres, and bole and canopy dripline locations in patches of mature mesquite trees in long-term grazed and long-term (70+ y) protected pastures were collected and analyzed for microbial community composition, biomass, potential exoenzyme activities, and a suite of biogeochemical characteristics. We found no differences in microbial communities or the soils associated with native vs. exotic grasses. Overall, mesquite bole patches differed from other patches in all soil characteristics except potential enzyme activity: soil temperature was significantly lower, and total carbon (C) and soil moisture were significantly higher. Potential activities were lowest for bare ground and highest at shrub dripline patches for all seven exoenzymes tested. Mean potential activities for C and phosphorous (P

  3. Influence of topography on density of grassland passerines in pastures

    USGS Publications Warehouse

    Renfrew, R.B.; Ribic, C.A.

    2002-01-01

    Pastures provide substantial habitat for grassland birds of management concern in the Driftless Area of southwestern Wisconsin. The rolling topography in this region is characterized by lowland valleys surrounded by relatively steep and often wooded slopes which are set apart from more expansive treeless uplands. We hypothesized that there would be lower densities of area sensitive grassland passerines in lowland grasslands compared to upland grasslands because of their preference for larger more open grasslands. To test this hypothesis and assess how well pasture area and vegetation structure predicted grassland passerine density compared to upland/lowland status, we conducted point counts of birds in 60 pastures in May-June 1997 and 1998. Upland pastures generally supported greater densities of grassland passerines than lowland pastures. Densities of Savannah sparrow (Passerculus sandwichensis) and bobolink (Dolichonyx oryzivorus) were significantly higher in upland pastures than in lowland pastures. Grasshopper sparrow (Ammodramus savannarum) density was significantly higher on uplands in one of the study years. The density of eastern meadowlark (Sturnella magna), western meadowlark (S. neglecta) and sedge wren (Cistothorus platensis) did not differ significandy between uplands and lowlands. Grassland passerine density was also predicted by pasture size and vegetation structure. Densities of bobolink and grasshopper sparrow were higher in larger pastures. Bobolink and Savannah sparrow occurred on pastures with greater vegetation height-density and less bare ground; bobolink also preferred shallower litter depths. Lowland pastures supported grassland bird species of management concern and should not be neglected. However, we recommend that pasture management for grassland passerines in areas of variable topography favor relatively large upland pastures that will contain higher densities of species of management concern.

  4. Seasonal recovery of Eimeria oocysts from soil on naturally contaminated pastures.

    PubMed

    Lassen, Brian; Lepik, Triin; Järvis, Toivo

    2014-03-01

    Though Eimeria is an important parasite of cattle, research is lacking on how the parasite persist in the pasture soils. In this study, feces samples were collected from three pastures in June and October 2010 and soil samples in April 2011. Coordinates of sampling locations were recorded with Global Positioning System together with information about grass cover, shade, and elevation. All soil samples were collected from the same locations as the fecal samples and used in model evaluating the possible factors influencing the concentration of oocysts in the soil. Feces and soil samples were investigated using a quantitative flotation technique. Eimeria oocysts were found in 95.6% of fecal samples collected in summer and 84.5% of samples in fall. In contrast, the same locations soil samples were positive for Eimeria oocysts in 37.3% (summer) and 44.3% (fall). Despite larger numbers of oocysts in fecal samples shed during summer compared to fall, there was no difference in the concentration of oocysts in soil samples the following spring. The odds of higher numbers of oocysts in soil samples in spring were higher if fecal samples collected in summer were in shade or if containing Eimeria alabamensis during the fall. Factors other than the concentrations of oocysts shed in feces appear to affect whether oocysts persist between grazing seasons.

  5. Soil Carbon and Nutrient Changes Associated with Deforestation for Pasture in Southern Costa Rica

    NASA Technical Reports Server (NTRS)

    Huth, Timothy J.; Porder, Stephen; Chaves, Joaquin; Whiteside, Jessica H.

    2012-01-01

    We assessed the effects of deforestation on soil carbon (C) and nutrient stocks in the premontane landscape near Las Cruces Biological Station in southern Costa Rica, where forests were cleared for pasture in the mid-1960s. We excavated six soil pits to a depth of 1 m in both pasture and primary forest, and found that C stocks were 20 kg C per square meters in both settings. Nevertheless, soil delta C-13 suggests 50 percent of the forest-derived soil C above 40 cm depth has turned over since deforestation. Soil nitrogen (N) and phosphorus (P) stocks derived from the soil pits were not significantly different between land uses (P = 0.43 and 0.61, respectively). At a larger spatial scale, however, the ubiquity of ruts produced by cattle-induced erosion indicates that there are substantial soil effects of grazing in this steep landscape. Ruts averaged 13 cm deep and covered 45 percent of the landscape, and thus are evidence of the removal of 0.7 Mg C/ ha/yr, and 70, 9 and 40 kg/ha/yr of N, P and potassium (K), respectively. Subsoils in this region are 10 times less C- and N-rich, and 2 times less P- and K-rich than the topsoil. Thus, rapid topsoil loss may lead to a decline in pasture productivity in the coming decades. These data also suggest that the soil C footprint of deforestation in this landscape may be determined by the fate of soil C as it is transported downstream, rather than C turnover in situ.

  6. Assessing pasture quality and degradation status using hyperspectral imaging: a case study from western Tibet

    NASA Astrophysics Data System (ADS)

    Lehnert, Lukas W.; Meyer, Hanna; Meyer, Nele; Reudenbach, Christoph; Bendix, Jörg

    2013-10-01

    Alpine grasslands on the Tibetan Plateau (TP) are suffering from pasture degradation induced by over-grazing, climate change and improper livestock management. Meanwhile, the status of pastures is largely unknown especially in poor accessible western parts on the TP. The aim of this case study was to assess the suitability of hyperspectral imaging to predict quality and amount of forage on the western TP. Therefore, 18 ground- based hyperspectral images taken along two transects on a winter pasture were used to estimate leaf chlorophyll content, photosynthetic-active vegetation cover (PV) and proportion of grasses. For calibration and validation purposes, chlorophyll content of 20 grass plants was measured in situ. From the images reference spectra of grass and non-grass species were collected. PV was assessed from similarity of images to mean vegetation spectra using spectral angle mapper and threshold classifications. A set of 48 previously published hyperspectral vegetation indices (VI) was used as predictors to estimate chlorophyll content and to discriminate grass and non-grass pixels. Separation into grass and non-grass species was performed using partial least squares (PLS) discriminant analysis and chlorophyll content was estimated with PLS regression. The accuracy of the models was assessed with leave-one-out cross validation and normalised root mean square errors (nRMSE) for chlorophyll and contingency matrices for grass classification and total PV separation. Highest error rates were observed for discrimination between vegetated and non-vegetated parts (Overall accuracy = 0.85), whilst accuracies of grass and non grass separation (Overall accuracy = 0.98) and chlorophyll estimation were higher (nRMSE = 10.7).

  7. Methane emissions from beef cattle grazing on semi-natural upland and improved lowland grasslands.

    PubMed

    Richmond, A S; Wylie, A R G; Laidlaw, A S; Lively, F O

    2015-01-01

    In ruminants, methane (CH4) is a by-product of digestion and contributes significantly to the greenhouse gas emissions attributed to agriculture. Grazed grass is a relatively cheap and nutritious feed but herbage species and nutritional quality vary between pastures, with management, land type and season all potentially impacting on animal performance and CH4 production. The objective of this study was to evaluate performance and compare CH4 emissions from cattle of dairy and beef origin grazing two grassland ecosystems: lowland improved grassland (LG) and upland semi-natural grassland (UG). Forty-eight spring-born beef cattle (24 Holstein-Friesian steers, 14 Charolais crossbred steers and 10 Charolais crossbred heifers of 407 (s.d. 29), 469 (s.d. 36) and 422 (s.d. 50) kg BW, respectively), were distributed across two balanced groups that grazed the UG and LG sites from 1 June to 29 September at stocking rates (number of animals per hectare) of 1.4 and 6.7, respectively. Methane emissions and feed dry matter (DM) intake were estimated by the SF6 tracer and n-alkane techniques, respectively, and BW was recorded across three experimental periods that reflected the progression of the grazing season. Overall, cattle grazed on UG had significantly lower (P<0.001) mean daily DM intake (8.68 v. 9.55 kg/day), CH4 emissions (176 v. 202 g/day) and BW gain (BWG; 0.73 v. 1.08 kg/day) than the cattle grazed on LG but there was no difference (P>0.05) in CH4 emissions per unit of feed intake when expressed either on a DM basis (20.7 and 21.6 g CH4 per kg DM intake for UG and LG, respectively) or as a percentage of the gross energy intake (6.0% v. 6.5% for UG and LG, respectively). However, cattle grazing UG had significantly (P<0.001) greater mean daily CH4 emissions than those grazing LG when expressed relative to BWG (261 v. 197 g CH4/kg, respectively). The greater DM intake and BWG of cattle grazing LG than UG reflected the poorer nutritive value of the UG grassland. Although

  8. 43 CFR 4130.5 - Free-use grazing permits.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Free-use grazing permits. 4130.5 Section... Authorizing Grazing Use § 4130.5 Free-use grazing permits. (a) A free-use grazing permit shall be issued to... directly and exclusively by the applicant and his family. The issuance of free-use grazing permits...

  9. 43 CFR 4130.5 - Free-use grazing permits.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Free-use grazing permits. 4130.5 Section... Authorizing Grazing Use § 4130.5 Free-use grazing permits. (a) A free-use grazing permit shall be issued to... directly and exclusively by the applicant and his family. The issuance of free-use grazing permits...

  10. 43 CFR 4130.5 - Free-use grazing permits.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Free-use grazing permits. 4130.5 Section... Authorizing Grazing Use § 4130.5 Free-use grazing permits. (a) A free-use grazing permit shall be issued to... directly and exclusively by the applicant and his family. The issuance of free-use grazing permits...

  11. 43 CFR 4130.5 - Free-use grazing permits.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Free-use grazing permits. 4130.5 Section... Authorizing Grazing Use § 4130.5 Free-use grazing permits. (a) A free-use grazing permit shall be issued to... directly and exclusively by the applicant and his family. The issuance of free-use grazing permits...

  12. 36 CFR 292.48 - Grazing activities.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... RECREATION AREAS Hells Canyon National Recreation Area-Federal Lands § 292.48 Grazing activities. The... their habitats; public outdoor recreation; conservation of scenic, wilderness, and scientific...

  13. Fertility Awareness

    MedlinePlus

    ... planning, periodic abstinence, and the rhythm method. How Does It Work? If a couple doesn't have ... get pregnant should not have sex. How Well Does It Work? Fertility awareness is not a reliable ...

  14. Transmission of foodborne zoonotic pathogens to riparian areas by grazing sheep

    PubMed Central

    Sutherland, Sara J.; Gray, Jeffrey T.; Menzies, Paula I.; Hook, Sarah E.; Millman, Suzanne T.

    2009-01-01

    The objective of this study was to determine if sheep grazing near riparian areas on pasture in Ontario are an important risk factor for the contamination of water with specific foodborne pathogens. Ten Ontario sheep farms were visited weekly for 12 wk during the summer of 2005. Samples of feces, soil, and water were collected and analyzed for the presence of Escherichia coli O157:H7, Salmonella spp., Campylobacter jejuni and C. coli, and Yersinia enterocolitica, by bacteriological identification and polymerase chain reaction (PCR). The data was analyzed as repeated measures over time using mixed models. No samples were positive for Salmonella, and no samples were confirmed positive for E. coli O157:H7 after PCR. Levels of Campylobacter were highest in the soil, but did not differ between soil where sheep grazed or camped and roadside soil that had never been grazed (P = 0.85). Levels of Yersinia were highest in water samples and were higher in soil where sheep had access (P = 0.01). The prevalence of positive Campylobacter and Yersinia samples were not associated with locations where sheep spent more time (Campylobacter P = 0.46, Yersinia P = 0.99). There was no effect of stocking density on the prevalence of Campylobacter (P = 0.30), but as the stocking density increased the levels of Yersinia increased (P = 0.04). It was concluded that although sheep transmit Yersinia to their environment, pastured sheep flocks are not major risk factors for the transmission of zoonotic pathogens into water. PMID:19436581

  15. Effect of heifer frame score on growth, fertility, and economics.

    PubMed

    Şentürklü, S; Landblom, D G; Perry, G A; Petry, T

    2015-01-01

    A non-traditional forage-based protocol was employed to evaluate replacement heifer growth, fertility, and economics between small frame (SF, 3.50; n = 50) and large frame (LF, 5.56; n = 50) heifers using three increasing gain growth phases. Preceding an 85 d growing-breeding period (Phase 3; P3) the heifers were managed as a common group for Phases 1 and 2 (P1 and P2). During P1, heifers grazed common fields of unharvested corn and corn residue (total digestible nutrients [TDN] 56%) with supplemental hay. For P2, heifers grazed early spring crested wheatgrass pasture (CWG; TDN 62%) that was followed by the final P3 drylot growing and breeding period (TDN 68%). Small frame heifers were lighter at the end of P1 in May and at the start of P3 breeding in August (p = 0.0002). Percent of mature body weight (BW) at the end of P1 (209 d) was 48.7% and 46.8%, respectively, for the SF and LF heifers and the percent pubertal was lower for SF than for LF heifers (18.0% vs 40.0%; p = 0.02). At breeding initiation (P3), the percentage of mature BW was 57.8 and 57.2 and the percentage pubertal was 90.0 and 96.0 (p = 0.07) for the SF and LF heifers, respectively; a 5-fold increase for SF heifers. Breeding cycle pregnancy on days 21, 42, and 63, and total percent pregnant did not differ (p>0.10). In drylot, SF heifer dry matter intake (DMI) was 20.1% less (p = 0.001) and feed cost/d was 20.3% lower (p = 0.001), but feed cost/kg of gain did not differ between SF and LF heifers (p = 0.41). Economically important live animal measurements for muscling were measured in May and at the end of the study in October. SF heifers had greater L. dorsi muscle area per unit of BW than LF heifers (p = 0.03). Small frame heifer value was lower at weaning (p = 0.005) and the non-pregnant ending heifer value was lower for SF heifers than for the LF heifers (p = 0.005). However, the total development cost was lower for SF heifers (p = 0.001) and the net cost per pregnant heifer, after accounting for

  16. Effect of Heifer Frame Score on Growth, Fertility, and Economics

    PubMed Central

    Şentürklü, S.; Landblom, D. G.; Perry, G. A.; Petry, T.

    2015-01-01

    A non-traditional forage-based protocol was employed to evaluate replacement heifer growth, fertility, and economics between small frame (SF, 3.50; n = 50) and large frame (LF, 5.56; n = 50) heifers using three increasing gain growth phases. Preceding an 85 d growing-breeding period (Phase 3; P3) the heifers were managed as a common group for Phases 1 and 2 (P1 and P2). During P1, heifers grazed common fields of unharvested corn and corn residue (total digestible nutrients [TDN] 56%) with supplemental hay. For P2, heifers grazed early spring crested wheatgrass pasture (CWG; TDN 62%) that was followed by the final P3 drylot growing and breeding period (TDN 68%). Small frame heifers were lighter at the end of P1 in May and at the start of P3 breeding in August (p = 0.0002). Percent of mature body weight (BW) at the end of P1 (209 d) was 48.7% and 46.8%, respectively, for the SF and LF heifers and the percent pubertal was lower for SF than for LF heifers (18.0% vs 40.0%; p = 0.02). At breeding initiation (P3), the percentage of mature BW was 57.8 and 57.2 and the percentage pubertal was 90.0 and 96.0 (p = 0.07) for the SF and LF heifers, respectively; a 5-fold increase for SF heifers. Breeding cycle pregnancy on days 21, 42, and 63, and total percent pregnant did not differ (p>0.10). In drylot, SF heifer dry matter intake (DMI) was 20.1% less (p = 0.001) and feed cost/d was 20.3% lower (p = 0.001), but feed cost/kg of gain did not differ between SF and LF heifers (p = 0.41). Economically important live animal measurements for muscling were measured in May and at the end of the study in October. SF heifers had greater L. dorsi muscle area per unit of BW than LF heifers (p = 0.03). Small frame heifer value was lower at weaning (p = 0.005) and the non-pregnant ending heifer value was lower for SF heifers than for the LF heifers (p = 0.005). However, the total development cost was lower for SF heifers (p = 0.001) and the net cost per pregnant heifer, after accounting for

  17. Effect of heifer frame score on growth, fertility, and economics.

    PubMed

    Şentürklü, S; Landblom, D G; Perry, G A; Petry, T

    2015-01-01

    A non-traditional forage-based protocol was employed to evaluate replacement heifer growth, fertility, and economics between small frame (SF, 3.50; n = 50) and large frame (LF, 5.56; n = 50) heifers using three increasing gain growth phases. Preceding an 85 d growing-breeding period (Phase 3; P3) the heifers were managed as a common group for Phases 1 and 2 (P1 and P2). During P1, heifers grazed common fields of unharvested corn and corn residue (total digestible nutrients [TDN] 56%) with supplemental hay. For P2, heifers grazed early spring crested wheatgrass pasture (CWG; TDN 62%) that was followed by the final P3 drylot growing and breeding period (TDN 68%). Small frame heifers were lighter at the end of P1 in May and at the start of P3 breeding in August (p = 0.0002). Percent of mature body weight (BW) at the end of P1 (209 d) was 48.7% and 46.8%, respectively, for the SF and LF heifers and the percent pubertal was lower for SF than for LF heifers (18.0% vs 40.0%; p = 0.02). At breeding initiation (P3), the percentage of mature BW was 57.8 and 57.2 and the percentage pubertal was 90.0 and 96.0 (p = 0.07) for the SF and LF heifers, respectively; a 5-fold increase for SF heifers. Breeding cycle pregnancy on days 21, 42, and 63, and total percent pregnant did not differ (p>0.10). In drylot, SF heifer dry matter intake (DMI) was 20.1% less (p = 0.001) and feed cost/d was 20.3% lower (p = 0.001), but feed cost/kg of gain did not differ between SF and LF heifers (p = 0.41). Economically important live animal measurements for muscling were measured in May and at the end of the study in October. SF heifers had greater L. dorsi muscle area per unit of BW than LF heifers (p = 0.03). Small frame heifer value was lower at weaning (p = 0.005) and the non-pregnant ending heifer value was lower for SF heifers than for the LF heifers (p = 0.005). However, the total development cost was lower for SF heifers (p = 0.001) and the net cost per pregnant heifer, after accounting for

  18. Human-Nature Interaction in the Eastern Pamirs of Tajikistan - Ecosystem services against the background of pasture use and energy consumption

    NASA Astrophysics Data System (ADS)

    Vanselow, K. A.; Samimi, C.; Kraudzun, T.; Kreutzmann, H.

    2012-04-01

    Mountains play an important role in the world's sustainable development. Despite the acquired knowledge about their importance the Global Environment Outlook 3 (UNEP 2002) states that most "mountain commons are ecologically under-managed and suffer from the classic 'commons syndrome': while all seek to benefit, stakeholders lack coordination, incentives and instruments for joint care." For the Eastern Pamirs, a dry (< 100 mm/a) and high (3,500-5,500 m asl) mountain plateau in the east of Tajikistan, grazing and fuel-wood are identified as key ecosystem services. Extensive pastoralism is a prime adapted land use strategy. Therefore, the Soviet administration allocated the production of meat on collective and state farms as the region's main task. Elaborate management plans, usually with four seasonal pasture camps, and additional imports of fuel and forage, led to a well-balanced utilization of all pastures. The dissolution of the USSR resulted in significant structural changes in the region. Most notably, the end of the subsidy system stopped the provisioning from outside. Without external inputs bridging long distances between the seasonal pastures poses a major problem to most smallholders. Furthermore, the limited supply and high cost of imported fossil fuels induced the increased use of dwarf shrubs as an energy resource. However, they are also important forage plants, particularly in winter. This study aims to provide a well-founded overview of the pasture and fuel-wood resources and the spatiotemporal variability of the actual pasture use with associated livestock numbers to make assertions on overuse in particular areas. Therefore, an interdisciplinary approach was used, combining geoecological and socio-economic methods. To assess the pasture potential information about land cover, phytomass availability, and forage quality were collected. Vegetation classes were modeled with a Random Forest (Breiman 2001), based on land cover information of 262 test plots

  19. A novel behavioral model of the pasture-based dairy cow from GPS data using data mining and machine learning techniques.

    PubMed

    Williams, M L; Mac Parthaláin, N; Brewer, P; James, W P J; Rose, M T

    2016-03-01

    A better understanding of the behavior of individual grazing dairy cattle will assist in improving productivity and welfare. Global positioning systems (GPS) applied to cows could provide a means of monitoring grazing herds while overcoming the substantial efforts required for manual observation. Any model of behavioral prediction using GPS needs to be accurate and robust by accounting for inter-cow variation as well as atmospheric effects. We evaluated the performance using a series of machine learning algorithms on GPS data collected from 40 pasture-based dairy cows over 4 mo. A feature extraction step was performed on the collected raw GPS data, which resulted in 43 different attributes. The evaluated behaviors were grazing, resting, and walking. Classifier learners were built using 10 times 10-fold cross validation and tested on an independent test set. Results were evaluated using a variety of statistical significance tests across all parameters. We found that final model selection depended upon level of performance and model complexity. The classifier learner deemed most suitable for this particular problem was JRip, a rule-based learner (classification accuracy=0.85; false positive rate=0.10; F-measure=0.76; area under the receiver operating curve=0.87). This model will be used in further studies to assess the behavior and welfare of pasture-based dairy cows.

  20. A novel behavioral model of the pasture-based dairy cow from GPS data using data mining and machine learning techniques.

    PubMed

    Williams, M L; Mac Parthaláin, N; Brewer, P; James, W P J; Rose, M T

    2016-03-01

    A better understanding of the behavior of individual grazing dairy cattle will assist in improving productivity and welfare. Global positioning systems (GPS) applied to cows could provide a means of monitoring grazing herds while overcoming the substantial efforts required for manual observation. Any model of behavioral prediction using GPS needs to be accurate and robust by accounting for inter-cow variation as well as atmospheric effects. We evaluated the performance using a series of machine learning algorithms on GPS data collected from 40 pasture-based dairy cows over 4 mo. A feature extraction step was performed on the collected raw GPS data, which resulted in 43 different attributes. The evaluated behaviors were grazing, resting, and walking. Classifier learners were built using 10 times 10-fold cross validation and tested on an independent test set. Results were evaluated using a variety of statistical significance tests across all parameters. We found that final model selection depended upon level of performance and model complexity. The classifier learner deemed most suitable for this particular problem was JRip, a rule-based learner (classification accuracy=0.85; false positive rate=0.10; F-measure=0.76; area under the receiver operating curve=0.87). This model will be used in further studies to assess the behavior and welfare of pasture-based dairy cows. PMID:26805984

  1. The influence of grazing and browsing on soil and runoff in revegetated erosion-areas

    NASA Astrophysics Data System (ADS)

    Markart, G.; Kohl, B.; Starnberger, R.; Gallmetzer, W.

    2009-04-01

    Intensive land use by grazing over centuries led to severe erosion at the steep slopes of the Tanaser Berg, in the community of Eyrs (South Tyrol - Italy). At the end of the 1970ies grazing was abandoned in the clearly eroded parts of the catchment above the actual timberline and an intensive program for revegetation of the slopes was started by the Department of Hydraulic Engineering, from the Autonomous Province of Bolzano, and the area covered by greening measures divided form the surrounding pastures by a solid fence. In 1999 partial opening for agricultural use by cattle for short term grazing (14 days a year) was planned in the interest of the land owners. Consequentially impact by cattle on the greened areas and alpine lawns still under long term grazing was investigated by use of a transportable spray irrigation for large plots (50 m² size) supplemented by additional investigations (documentation of soil physical properties, characterization of vegetation, changes in plant biomass, etc.). Each plot was irrigated twice: One time before opening the fenced site for short time grazing by cattle again at the End of June and the beginning of July 1999 and a second time five years later, after restart of short time grazing at the beginning of August 2004. In total seven plots were irrigated. 5 plots within the revegetated area, four of them greened, the fifth a carex sempervirens stand, formerly not eroded. 2 of the greened plots were fenced and kept free from grazing over the next five years. In addition 2 carex sempervirens stands with calluna outside which had been grazed at leat for several decades, one of them partially eroded, were investigated as reference plots. The four revegetated plots did not show significant changes in surface runoff development. High content of skeleton (stones and blocs) reduced runoff and erosion potential. In addition high slope-inclination made these plots unloved by cattle. On the contrary the natural carex sempervirens

  2. Dynamics of Theileria orientalis genotype population in cattle in a year-round grazing system.

    PubMed

    Masatani, Tatsunori; Yoshihara, Shunpei; Matsubara, Atsuko; Gotoh, Takafumi; Takahashi, Hideyuki; Tanaka, Tetsuya; Andoh, Masako; Endo, Yasuyuki; Matsuo, Tomohide

    2016-03-01

    Theirelia orientalis is a tick-borne haemoprotozoan parasite, and infection with this parasite is one of the most important diseases for grazing cattle. Co-infection of cattle with different genotypes of T. orientalis often occurs. In this study, we investigated the temporal dynamics of genotypes in cattle in a year-round grazing system in Japan. Genotype-specific PCR assays to determine major piroplasm surface protein (MPSP) genotypes (types 1 to 5) of T. orientalis were performed by using time-course blood samples collected from grazing cattle and ticks in a pasture. All 20 cattle investigated in this study were infected with T. orientalis. By using genotype-specific PCR, we detected the combination of genotypes of T. orientalis (types 1 to 5) from each cattle. These multiple genotypes of T. orientalis were also confirmed in ticks. Notably, each genotype of T. orientalis in cattle was temporally detected from cattle and more variable genotypes were found in summer. The observed temporal dynamics of the MPSP genotypes of T. orientalis in cattle could be explained by host immunity against the parasites or genetic recombination of parasite in ticks. PMID:27078669

  3. Individual personality and the spatial distribution of groups of grazing animals: an example with sheep.

    PubMed

    Sibbald, Angela M; Erhard, Hans W; McLeod, James E; Hooper, Russell J

    2009-11-01

    Impacts of individual personality on group distribution were investigated using sheep (Ovis aries) as a model. In an indoor exploration test, individuals who visited <4 (out of 6) objects in a novel environment were classified as 'shy' (n=10), and those who visited 5 or 6 objects were classified as 'bold' (n=10). Nine weeks later, using a series of groups (n=40) of either 5 shy or 5 bold sheep, we measured distribution at pasture and responses to disturbance and the approach of a human handler. When grazing undisturbed, the mean nearest neighbour distance and spread (minimum convex hull area) of shy groups were less than those of bold groups, with shy individuals moving towards one another more often. Shy groups explored a smaller area than bold groups. When disturbed, shy sheep were more likely to stop grazing and move closer together. Shy sheep kept further away from the handler and moved faster when driven. The results demonstrate a link between personality and group distribution, suggesting that our 'shy' and 'bold' individuals may occupy different positions on the shy-bold continuum documented for other species. We discuss implications for diet composition and impacts on vegetation grazed by animals with different personalities.

  4. Staggers in horses grazing paspalum infected with Claviceps paspali.

    PubMed

    Cawdell-Smith, A J; Scrivener, C J; Bryden, W L

    2010-10-01

    Invasion of the flowering heads of grasses by Claviceps spp. can produce sclerotia (ergots) containing several toxins. Ingestion of these toxins, through the consumption of paspalum (Paspalum dilatatum), can induce a range of clinical symptoms, including staggers. Cattle are the most commonly affected species, but although sheep and horses have been reported affected there are no published descriptions of paspalum staggers in horses. We describe two occurrences of paspalum staggers, the first in three Australian Stockhorse foals and the second in mature Standardbred horses. All three foals presented with ataxia in all limbs after consuming infected paspalum. One foal died from misadventure and the other two recovered within 1 week of removal from the infected paddock. In the second case, two of eight mares and geldings grazing in an irrigation channel developed hindquarter paresis. After removal of all horses from the area, one of the affected horses continued to deteriorate. Both horses were treated with antibiotics. The more severely affected horse was also treated with fluids and electrolytes, but had to be euthanased. The second affected horse recovered after 2 days. Paspalum pastures should inspected for Claviceps paspali infection before the introduction of horses. PMID:20854295

  5. Phenolic responses of mountain crowberry (Empetrum nigrum ssp. hermaphroditum) to global climate change are compound specific and depend on grazing by reindeer (Rangifer tarandus).

    PubMed

    Väisänen, Maria; Martz, Françoise; Kaarlejärvi, Elina; Julkunen-Tiitto, Riitta; Stark, Sari

    2013-12-01

    Mountain crowberry (Empetrum nigrum ssp. hermaphroditum) is a keystone species in northern ecosystems and exerts important ecosystem-level effects through high concentrations of phenolic metabolites. It has not been investigated how crowberry phenolics will respond to global climate change. In the tundra, grazing by reindeer (Rangifer tarandus) affects vegetation and soil nutrient availability, but almost nothing is known about the interactions between grazing and global climate change on plant phenolics. We performed a factorial warming and fertilization experiment in a tundra ecosystem under light grazing and heavy grazing and analyzed individual foliar phenolics and crowberry abundance. Crowberry was more abundant under light grazing than heavy grazing. Although phenolic concentrations did not differ between grazing intensities, responses of crowberry abundance and phenolic concentrations to warming varied significantly depending on grazing intensity. Under light grazing, warming increased crowberry abundance and the concentration of stilbenes, but decreased e.g., the concentrations of flavonols, condensed tannins, and batatasin-III, resulting in no change in total phenolics. Under heavy grazing, warming did not affect crowberry abundance, and induced a weak but consistent decrease among the different phenolic compound groups, resulting in a net decrease in total phenolics. Our results show that the different phenolic compound groups may show varying or even opposing responses to warming in the tundra at different levels of grazing intensity. Even when plant phenolic concentrations do not directly respond to grazing, grazers may have a key control over plant responses to changes in the abiotic environment, reflecting multiple adaptive purposes of plant phenolics and complex interactions between the biotic and the abiotic factors.

  6. MEASURING INVERTEBRATE GRAZING ON SEAGRASSES AND EPIPHYTES

    EPA Science Inventory

    The chapter describes methods to assess grazing rates, grazer preferences, and grazer impacts, by mobile organisms living in the canopy or in the rhizome layer in any seagrass system. One set of methods quantifies grazing activity in small to medium sized, mobile organisms livin...

  7. 25 CFR 173.6 - Stock grazing.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Stock grazing. 173.6 Section 173.6 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER CONCESSIONS, PERMITS AND LEASES ON LANDS WITHDRAWN OR ACQUIRED IN CONNECTION WITH INDIAN IRRIGATION PROJECTS § 173.6 Stock grazing. Permittees...

  8. 25 CFR 173.6 - Stock grazing.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Stock grazing. 173.6 Section 173.6 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER CONCESSIONS, PERMITS AND LEASES ON LANDS WITHDRAWN OR ACQUIRED IN CONNECTION WITH INDIAN IRRIGATION PROJECTS § 173.6 Stock grazing. Permittees...

  9. 25 CFR 173.6 - Stock grazing.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Stock grazing. 173.6 Section 173.6 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER CONCESSIONS, PERMITS AND LEASES ON LANDS WITHDRAWN OR ACQUIRED IN CONNECTION WITH INDIAN IRRIGATION PROJECTS § 173.6 Stock grazing. Permittees...

  10. 25 CFR 173.6 - Stock grazing.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Stock grazing. 173.6 Section 173.6 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER CONCESSIONS, PERMITS AND LEASES ON LANDS WITHDRAWN OR ACQUIRED IN CONNECTION WITH INDIAN IRRIGATION PROJECTS § 173.6 Stock grazing. Permittees...

  11. Trace-elements in sheep grazing near a lead-zinc smelting complex at Port Pirie, South Australia

    SciTech Connect

    Koh, T.S.; Judson, G.J.

    1986-07-01

    In South Australia, several studies have shown that heavy metal pollution of soils and plants occurs in the vicinity of a lead/zinc smelter at Port Pirie. Data on soil analysis indicates that at least 3400 km/sup 2/ of land near these smelters has been contaminated by the fallout of Pb, Zn and Cd. It is possible that contamination of soil and pasture by heavy metals may adversely affect the health of livestock grazing near the smelters. In sheep, Pb toxicity causes anorexia, abdominal pain and diarrhea while Zn or Cd supplementation reduces the Cu status. This study was undertaken to investigate the effects of heavy metals on the trace-element status of sheep grazing at selected distances from the Port Pirie smelters.

  12. The effects of China's environmental protection policies on pasture quality and the activities of small-scale herders in Songpan County, Western Sichuan.

    PubMed

    Veeck, Gregory; Li, Zhou; Yu, Fawen; Emerson, Charles

    2015-06-01

    Since 2000, there has been an ambitious governmental effort to protect China's grassland resources through new, often controversial, policies and programs backed up by massive capital investments and subsidies. The policies are intended to protect pastoral ecological systems while allowing the pasture-based husbandry sector to continue to evolve in ways that assure acceptable revenues to affected families and regions. This article reports results of a case study conducted in Songpan County of western Sichuan during the fall of 2013 specifically focused on these issues and interactions. The mixed-method research combines remotely sensed MODIS vegetation indices (EVI), livestock counts by type, and grassland area estimates at the township scale from 2000-2012, with depth interviews with local herding families and husbandry officials to determine how the husbandry sector has changed in the past 12 years under post-2000 policy interventions. Results for Songpan indicate that pasture coverage has improved slightly as grazing livestock density per hectare declined, but herders and local officials report that some of the new laws and programs have important unanticipated negative impacts on pasture quality, pasture ecology, and economic returns from herding for some families. PMID:25995138

  13. Consistent ozone-induced decreases in pasture forage quality across several grassland types and consequences for UK lamb production.

    PubMed

    Hayes, Felicity; Mills, Gina; Jones, Laurence; Abbott, John; Ashmore, Mike; Barnes, Jeremy; Neil Cape, J; Coyle, Mhairi; Peacock, Simon; Rintoul, Naomi; Toet, Sylvia; Wedlich, Kerstin; Wyness, Kirsten

    2016-02-01

    In this study we have demonstrated that rising background ozone has the potential to reduce grassland forage quality and explored the implications for livestock production. We analysed pasture samples from seven ozone exposure experiments comprising mesotrophic, calcareous, haymeadow and sanddune unimproved grasslands conducted in open-top chambers, solardomes and a field release system. Across all grassland types, there were significant increases in acid detergent fibre, crude fibre and lignin content with increasing ozone concentration, resulting in decreased pasture quality in terms of the metabolisable energy content of the vegetation. We derived a dose-response function for metabolisable energy of the grassland with ozone concentration, applicable to a range of grassland types, and used this to predict effects on pasture quality of UK vegetation at 1 km resolution using modelled ozone data for 2007 and for predicted higher average ozone concentrations in 2020. This showed a potential total reduction in lamb production in the UK of approximately 4% in 2020 compared to 2007. The largest impacts were in geographical areas of modest ozone increases between the two years, but where large numbers of lambs were present. For an individual farmer working to a very small cost margin this could represent a large reduction in profit, both in regions where the impacts per lamb and those where the impacts per km(2) of grazing land are largest. In the short term farmers could adapt their lamb management in response to changed forage quality by additional supplementary feed of high metabolisable energy content. Nationally this increase in annual additional feed in 2020 compared to 2007 would be 2,166 tonnes (an increase of 0.7%). Of added concern are the longer-term consequences of continual deterioration of pasture quality and the implications for changes in farming practices to compensate for potential reductions in livestock production capacity.

  14. Productive performance, meat quality and fatty acid profile of steers finished in confinement or supplemented at pasture.

    PubMed

    Patino, H O; Medeiros, F S; Pereira, C H; Swanson, K C; McManus, C

    2015-06-01

    Thirty Aberdeen Angus crossbred steers (281 ± 16 kg) were used to test the effect of finishing feeding system on growth performance, meat quality and fatty acid (FA) profile in intramuscular fat. Steers were fed in confinement (forage:concentrate ratio of 50 : 50; DM basis) or with different levels of energy supplementation (0, 0.4, 0.8 and 1.2% BW) at pasture (Avena strigosa Schreb and Lolium multiflorum L.). There were no differences between treatments for ADG (average=1.60 kg/day), hot carcass weight (HCW) (average=229 kg) and subcutaneous fat depth (average=3 mm). Dressing % (P=0.06; tendency) and carcass ADG (P=0.02) linearly increased with level of supplementation for pasture steers. No differences were observed between treatments for tenderness, marbling, pH, color b*, or cooking loss and drip loss in samples of Longissimus dorsi. However L* increased linearly (P=0.05) with level of supplementation. The concentrations of myristic, palmitic, estearic and linoleic FA did not differ among treatments. The concentration of n-3 FA increased (P<0.001) in steers at pasture compared with confinement, but n-6 FA concentrations did not differ between feeding system. Supplementation up to 0.4% BW increase (P<0.001) conjugated linoleic acid (CLA) and linolenic FA concentrations in intramuscular fat when compared with confinement. The level of supplementation on pasture linearly decreased (P<0.001) n-3 and CLA and linearly increased (P=0.001) the n-6 : n-3 ratio. Finishing of steers grazing winter pasture with energy supplementation or in confinement fed a medium-concentrate diet did not affect meat quality (tenderness, marbling, parameter b* on the CIE L*a*b* scale, cooking and drip losses) except for a* and L*. However, intramuscular fat of animals finished at pasture with moderate level of supplementation compared to animals fed in confinement had greater concentration of CLA, linolenic, and n-3, and lower n-6 : n-3 in intramuscular fat.

  15. 5. East and north (rear) elevations of the horse pasture ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. East and north (rear) elevations of the horse pasture store, looking southwest; the store's two outbuildings can ben seen at the right of the view - Horsepasture Store, U.S. Route 58 & State Route 687, Horse Pasture, Henry County, VA

  16. 4. West and south elevations of the horse pasture store, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. West and south elevations of the horse pasture store, looking northeast; a "Greenhouse" structure can be seen extending to the west of the store at the left of the view - Horsepasture Store, U.S. Route 58 & State Route 687, Horse Pasture, Henry County, VA

  17. 2. Overall view of the horse pasture store from the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Overall view of the horse pasture store from the east; U.S. Highway 58 runs from left to right across the view, while Route 687 rices into the distance at the left - Horsepasture Store, U.S. Route 58 & State Route 687, Horse Pasture, Henry County, VA

  18. Influence of transient flooding on methane fluxes from subtropical pastures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seasonally flooded subtropical pastures are major methane (CH4) sources, where transient flooding drives episodic and high-magnitude emissions from the underlying landscape. Understanding the mechanisms that drive these patterns is needed to better understand pasture CH4 emissions and their response...

  19. Productivity, botanical composition, and nutritive value of commercial pasture mixtures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pastures in the northeastern USA often are planted to mixtures of grasses and legumes. There is limited public sector information on the performance of commercial forage mixtures. We evaluated a range of commercial pasture mixtures to determine if the number of species in a mixture affected yield an...

  20. Effects of supplementation on intake, digestion, and performance of beef cattle consuming fertilized, stockpiled bermudagrass forage.

    PubMed

    Wheeler, J S; Lalman, D L; Horn, G W; Redmon, L A; Lents, C A

    2002-03-01

    Experiments were conducted to determine the effects of increasing supplement protein concentration on performance and forage intake of beef cows and forage utilization of steers consuming stockpiled bermudagrass forage. Bermudagrass pastures were fertilized with 56 kg of N/ha in late August. Grazing was initiated during early November and continued through the end of January each year. Treatments for the cow performance trials were: no supplement or daily equivalents of 0.2, 0.4, and 0.6 g of supplemental protein per kilogram of BW. Supplements were formulated to be isocaloric, fed at the equivalent of 0.91 kg/d, and prorated for 4 d/wk feeding. Varying the concentration of soybean hulls and soybean meal in the supplements created incremental increases in protein. During yr 1, supplemented cows lost less weight and condition compared to unsupplemented animals (P < 0.05). During yr 2, supplemented cows gained more weight (P = 0.06) and lost less condition (P < 0.05) compared to unsupplemented cows. Increasing supplement protein concentration had no affect on cumulative cow weight change or cumulative body condition score change. Forage intake tended to increase (P = 0.13, yr 1 and P = 0.07, yr 2) in supplemented cows. Supplement protein concentration did not alter forage intake. In a digestion trial, four crossbred steers were used in a Latin square design to determine the effects of supplement protein concentration on intake and digestibility of hay harvested from stockpiled bermudagrass pasture. Treatments were no supplement; or 0.23, 0.46, and 0.69 g of supplemental protein per kilogram of BW. Forage intake increased (P < 0.05) 16% and OM intake increased (P < 0.01) 30% in supplemented compared to unsupplemented steers. Diet OM digestibility increased (P = 0.08) 14.5% and total digestible OM intake increased (P < 0.05) 49% in supplemented compared to unsupplemented steers. Supplement protein concentration did not alter forage intake, total digestible OM intake

  1. Drinking water intake of grazing steers: the role of environmental factors controlling canopy wetness.

    PubMed

    Sun, L Z; Auerswald, K; Wenzel, R; Schnyder, H

    2014-01-01

    Cattle obtain water primarily from the moisture in their feed and from drinking water. On pasture, the moisture content of the diet is influenced by plant tissue water (internal water) and surface moisture (external water), which may include dew, guttation, and intercepted rain, that influence the drinking water requirement. This study investigated the relationship between daily drinking water intake (DWI, L/d) of steers on pasture (19 steers with mean initial BW of approximately 400 kg) and soil and weather factors that are known to affect plant water status (dry matter content) and surface moisture formation and persistence. Daily records of weather conditions and DWI were obtained during 2 grazing seasons with contrasting spring, summer, and autumn rainfall patterns. Plant available water in the soil (PAW, mm) was modeled from actual and potential evapotranspiration and the water-holding capacity of the soil. The DWI averaged over the herd varied among days from 0 to 29 L/d (grazing season mean 9.8 L/d). The DWI on both dry (<0.2 mm rainfall on the corresponding and previous days) and wet (>2 mm) days increased with increasing temperature (mean, maximum, and minimum), sunshine hours, and global radiation and decreasing relative humidity, and the slopes and coefficients of determination were generally greater for wet days. Wind reduced DWI on wet days but had no effect on dry days. The DWI was reduced by up to 4.4 L/d on wet days compared to dry days, but DWI did not correlate with rainfall amount. Increasing PAW decreased DWI by up to >10 L/d on both dry and wet days. These results are all consistent with environmental effects on the water status (dry matter content) of pasture vegetation and canopy surface moisture, the associated effects on grazing-related water intake, and the corresponding balancing changes of DWI. Using the observed relationships with environmental factors, we derived a new model predicting DWI for any soil moisture condition, for both wet

  2. Grazing impacts on the susceptibility of rangelands to wind erosion: The effects of stocking rate, stocking strategy and land condition

    NASA Astrophysics Data System (ADS)

    Aubault, Hélène; Webb, Nicholas P.; Strong, Craig L.; McTainsh, Grant H.; Leys, John F.; Scanlan, Joe C.

    2015-06-01

    An estimated 110 Mt of dust is eroded by wind from the Australian land surface each year, most of which originates from the arid and semi-arid rangelands. Livestock production is thought to increase the susceptibility of the rangelands to wind erosion by reducing vegetation cover and modifying surface soil stability. However, research is yet to quantify the impacts of grazing land management on the erodibility of the Australian rangelands, or determine how these impacts vary among land types and over time. We present a simulation analysis that links a pasture growth and animal production model (GRASP) to the Australian Land Erodibility Model (AUSLEM) to evaluate the impacts of stocking rate, stocking strategy and land condition on the erodibility of four land types in western Queensland, Australia. Our results show that declining land condition, over stocking, and using inflexible stocking strategies have potential to increase land erodibility and amplify accelerated soil erosion. However, land erodibility responses to grazing are complex and influenced by land type sensitivities to different grazing strategies and local climate characteristics. Our simulations show that land types which are more resilient to livestock grazing tend to be least susceptible to accelerated wind erosion. Increases in land erodibility are found to occur most often during climatic transitions when vegetation cover is most sensitive to grazing pressure. However, grazing effects are limited during extreme wet and dry periods when the influence of climate on vegetation cover is strongest. Our research provides the opportunity to estimate the effects of different land management practices across a range of land types, and provides a better understanding of the mechanisms of accelerated erosion resulting from pastoral activities. The approach could help further assessment of land erodibility at a broader scale notably if combined with wind erosion models.

  3. Remnant Pachira quinata pasture trees have greater opportunities to self and suffer reduced reproductive success due to inbreeding depression.

    PubMed

    Rymer, P D; Sandiford, M; Harris, S A; Billingham, M R; Boshier, D H

    2015-08-01

    Habitat fragmentation is extensive throughout the world, converting natural ecosystems into fragments of varying size, density and connectivity. The potential value of remnant trees in agricultural landscapes as seed sources and in connecting fragments has formed a fertile area of debate. This study contrasted the mating patterns of bat-pollinated Pachira quinata trees in a continuous forest to those in pasture through microsatellite-based paternity analysis of progeny. The breeding system was determined by analysis of pollen tube growth and seed production from controlled pollinations. Fitness of selfed and outcrossed seed was compared by germination and seedling growth. There was more inbreeding within pasture trees (outcrossing=0.828±0.015) compared with forest trees (0.926±0.005). Pasture trees had fewer sires contributing to mating events, but pollen dispersal distances were greater than those in the forest. Paternity analysis showed variation in outcrossing rates among pasture trees with high proportions of external and self pollen sources detected. A leaky self-incompatibility system was found, with self pollen having reduced germination on stigmas and slower growth rate through the style. Controlled pollinations also showed a varied ability to self among trees, which was reflected in the selfing rates among pasture trees shown by the paternity analysis (0-80% selfing). Self pollination resulted in lower seed set, germination and seedling growth compared with outcrossing. While remnant trees in agricultural landscapes are involved in broader mating patterns, they show increased but varied levels of inbreeding, which result in reduced fitness.

  4. A pilot project combining multispectral proximal sensors and digital cameras for monitoring tropical pastures

    NASA Astrophysics Data System (ADS)

    Handcock, Rebecca N.; Gobbett, D. L.; González, Luciano A.; Bishop-Hurley, Greg J.; McGavin, Sharon L.

    2016-08-01

    Timely and accurate monitoring of pasture biomass and ground cover is necessary in livestock production systems to ensure productive and sustainable management. Interest in the use of proximal sensors for monitoring pasture status in grazing systems has increased, since data can be returned in near real time. Proximal sensors have the potential for deployment on large properties where remote sensing may not be suitable due to issues such as spatial scale or cloud cover. There are unresolved challenges in gathering reliable sensor data and in calibrating raw sensor data to values such as pasture biomass or vegetation ground cover, which allow meaningful interpretation of sensor data by livestock producers. Our goal was to assess whether a combination of proximal sensors could be reliably deployed to monitor tropical pasture status in an operational beef production system, as a precursor to designing a full sensor deployment. We use this pilot project to (1) illustrate practical issues around sensor deployment, (2) develop the methods necessary for the quality control of the sensor data, and (3) assess the strength of the relationships between vegetation indices derived from the proximal sensors and field observations across the wet and dry seasons. Proximal sensors were deployed at two sites in a tropical pasture on a beef production property near Townsville, Australia. Each site was monitored by a Skye SKR-four-band multispectral sensor (every 1 min), a digital camera (every 30 min), and a soil moisture sensor (every 1 min), each of which were operated over 18 months. Raw data from each sensor was processed to calculate multispectral vegetation indices. The data capture from the digital cameras was more reliable than the multispectral sensors, which had up to 67 % of data discarded after data cleaning and quality control for technical issues related to the sensor design, as well as environmental issues such as water incursion and insect infestations. We recommend

  5. Evaluation of Brassicas in grazing systems for sheep: I. Quality of forage and animal performance.

    PubMed

    Reid, R L; Puoli, J R; Jung, G A; Cox-Ganser, J M; McCoy, A

    1994-07-01

    Four years of grazing trials were conducted with Brassica forages to evaluate their chemical composition and effect on ADG of fattening lambs and breeding ewes in late fall. Brassicas tested included kales (Brassica oleracea L. var. acephala DC), turnips (B. rapa L.), and a chinese cabbage hybrid (B. rapa L. x B. pekinensis [Lour.] Rupr.). Daily gains of lambs varied widely among years (19 to 330 g/d); ADG on Brassicas were, however, generally higher than on stockpiled Kentucky 31 tall fescue (Festuca arundinacea Schreb.) or orchardgrass (Dactylis glomerata L.)-red clover (Trifolium pratense L.) pastures grazed at the same time. In 1 yr, dietary supplementation of lambs grazing a hybrid turnip (Forage Star) with iodine and copper oxide needles improved (P < .05) ADG; however, there was no effect on gains in two later years. In 2 yr, lambs showed higher ADG on Tyfon chinese cabbage hybrid (241 and 330 g/d) than on Forage Star turnip (197 and 275 g/d) or stockpiled grass-clover (135 and 233 g/d), but yield of Tyfon was lower. Indications that supplementary hay improved ADG of lambs and ewes were not confirmed in the final year, in which hay increased (P < .05) ADG of lambs in the first 3 wk of grazing Brassicas but decreased gains later. Thyroid weights were increased (P < .01) consistently in all trials on Brassicas, but enlargement was modest and not related to ADG. Brassica forages provided high yields (5.6 to 10.5 t/ha) of DM in the late fall to early winter period, with high carrying capacity for sheep but large variability in ADG.

  6. Efficiency to reach age of puberty and behaviour of buffalo heifers (Bubalus bubalis) kept on pasture or in confinement.

    PubMed

    Sabia, E; Napolitano, F; De Rosa, G; Terzano, G M; Barile, V L; Braghieri, A; Pacelli, C

    2014-11-01

    In order to evaluate the influence of rearing system (free-ranging (FR) v. confinement (C)) on buffalo heifer efficiency to reach age of puberty and on behavioural and immune functions, two experiments were conducted from September 2010 to October 2011. In Experiment I, 32 subjects aged 8 to 9 months at the start of experiment were used. A total of 16 animals (group C) were group housed in an indoor slatted floor pen (4 m2/animal) with an outdoor paddock (4 m2/animal); 16 others grazed on a Mediterranean natural pasture of 40 ha (group FR). Behavioural data were collected and organic matter digestibility, blood metabolites and progesterone were determined. At the end of the experiment, a novel object test and a skin test were conducted, and the avoidance distance (AD) at the manger was measured. Free-ranging animals were able to express natural behaviours such as wallowing and grazing. C animals devoted more time to the novel object than FR animals, whereas AD at manger was lower in group FR than in group C (P<0.01). Cellular immune response was higher in FR heifers than in C animals (P<0.01). FR animals also showed a higher digestibility of organic matter (P<0.01). Heifers from group FR had higher plasma concentrations of non-esterified fatty acids (P<0.001) and lower concentrations of glucose than heifers from group C (P<0.001). C animals showed higher daily weight gains (P<0.01) and weight at the puberty (P<0.05), but there were no differences in terms of age of puberty between the two groups. The intakes of dry matter (DM), CP and energy to reach the age of puberty were similar in both groups. In order to verify whether the results obtained in Experiment I could be replicated in different rearing conditions (reduced pasture availability, different location and altitude), a second experiment was conducted on 26 animals, where only onset of age of puberty and metabolic profile were monitored. In Experiment II, 13 heifers grazed on a natural pasture of 5 ha, other

  7. Efficiency to reach age of puberty and behaviour of buffalo heifers (Bubalus bubalis) kept on pasture or in confinement.

    PubMed

    Sabia, E; Napolitano, F; De Rosa, G; Terzano, G M; Barile, V L; Braghieri, A; Pacelli, C

    2014-11-01

    In order to evaluate the influence of rearing system (free-ranging (FR) v. confinement (C)) on buffalo heifer efficiency to reach age of puberty and on behavioural and immune functions, two experiments were conducted from September 2010 to October 2011. In Experiment I, 32 subjects aged 8 to 9 months at the start of experiment were used. A total of 16 animals (group C) were group housed in an indoor slatted floor pen (4 m2/animal) with an outdoor paddock (4 m2/animal); 16 others grazed on a Mediterranean natural pasture of 40 ha (group FR). Behavioural data were collected and organic matter digestibility, blood metabolites and progesterone were determined. At the end of the experiment, a novel object test and a skin test were conducted, and the avoidance distance (AD) at the manger was measured. Free-ranging animals were able to express natural behaviours such as wallowing and grazing. C animals devoted more time to the novel object than FR animals, whereas AD at manger was lower in group FR than in group C (P<0.01). Cellular immune response was higher in FR heifers than in C animals (P<0.01). FR animals also showed a higher digestibility of organic matter (P<0.01). Heifers from group FR had higher plasma concentrations of non-esterified fatty acids (P<0.001) and lower concentrations of glucose than heifers from group C (P<0.001). C animals showed higher daily weight gains (P<0.01) and weight at the puberty (P<0.05), but there were no differences in terms of age of puberty between the two groups. The intakes of dry matter (DM), CP and energy to reach the age of puberty were similar in both groups. In order to verify whether the results obtained in Experiment I could be replicated in different rearing conditions (reduced pasture availability, different location and altitude), a second experiment was conducted on 26 animals, where only onset of age of puberty and metabolic profile were monitored. In Experiment II, 13 heifers grazed on a natural pasture of 5 ha, other

  8. Grazing as an alternative for utilization of saline-sodic soils in the San Joaquin Valley: selenium accretion and performance of beef heifers.

    PubMed

    Juchem, Sérgio O; Benes, Sharon E; Robinson, P H; Grattan, Stephen R; Vasquez, Pablo; Chilibroste, Pablo; Brito, Martin

    2012-03-01

    Two experiments were conducted to evaluate Se accumulation and health of non-pregnant, non-breeding beef cattle grazing on forages with a high Se content due to irrigation with saline drainage water. Heifers grazed experimental pastures of "Jose" tall wheatgrass (TWG; Thinopyrum ponticum var. "Jose") and creeping wildrye (CWR; Leymus triticoides var. "Rio") for 190 days in Experiment 1 (2007) and for 165 days in Experiment 2 (2008). In experiment 1, mean Se concentrations were similar in TWG and CWR herbage (4.0 versus 3.7 ± 0.26 mg/kg dry weight; p=0.34) as was crude protein (113 versus 114 ± 7.9 g/kg dry weight; p=0.94). Concentrations of Se in blood increased by 300% during the grazing period, and were similar for heifers grazing the TWG or CWR pastures (0.94 versus 0.87 ± 0.03 mg/kg; p=0.89). Heifers grazing on TWG gained more body weight than did heifers grazing on CWR (0.59 versus 0.27 ± 0.07 kg/days; p<0.01). In experiment 2, concentration of Se (4.0 versus 2.8 mg/kg ± 0.19 mg/kg dry weight; p<0.01) and crude protein (79 versus 90 ± 5.6 g/kg dry weight; p<0.01) differed, for TWG and CWR, respectively. Within 20 days, Se concentrations in blood had increased by 300% and by nearly 200% in heifers grazing on TWG or CWR. All data cited are least square means ± standard error of the mean. Data from our two grazing seasons are consistent in demonstrating the safety of grazing beef cattle for a period of up to 6 months on TWG and CWR forages having high levels of Se due to irrigation with saline drainage water. This suggests that forage production using saline drainage water is a viable alternative for saline soils with limited potential for producing high value, salt-sensitive, crops.

  9. Differential rumination, intake, and enteric methane production of dairy cows in a pasture-based automatic milking syst