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Sample records for hoggets

  1. Age and nutrition influence the concentrations of three branched chain fatty acids in sheep fat from Australian abattoirs.

    PubMed

    Watkins, P J; Rose, G; Salvatore, L; Allen, D; Tucman, D; Warner, R D; Dunshea, F R; Pethick, D W

    2010-11-01

    The characteristic mutton odour, associated with the cooked meat of older sheep, can be problematic for some consumers who find the odour disagreeable. Branch chain fatty acids (BCFAs) are considered to be the main determinants of mutton odour. In this study, the aim was to identify the factors influencing the BCFA content of animals at abattoirs in Australia. Samples of subcutaneous fat from over the chump (gluteus medius) were collected from 533 sheep carcasses at abattoirs in New South Wales, Victoria and Western Australia. The carcasses were from sheep differing in age, gender, breed and nutrition. The concentrations of three branched chain fatty acids (BCFAs); namely, 4-methyloctanoic (MOA), 4-ethyloctanoic (EOA) and 4-methylnonanoic acids (MNA), were determined. Statistical modelling showed that, with pre-slaughter nutrition in the model as a random term, BCFA concentrations could be used for discriminating the age of sheep. Fat samples from lamb carcasses had lower MOA and EOA concentrations and a higher concentration of MNA in comparison to hogget and mutton (P<0.05). When nutrition was excluded as a random effect from the statistical model, the MOA and MNA concentrations did not differentiate between lamb, hogget and mutton whereas, for EOA, lamb had a lower concentration than mutton (P<0.05) with hogget intermediate. An interaction existed between age and gender (P<0.05) where female lambs had lower EOA concentrations relative to the mutton but not for castrates.

  2. Artificial insemination of Cashmere goats: effects on fertility and fecundity of intravaginal treatment, method and time of insemination, semen freezing process, number of motile spermatozoa and age of females.

    PubMed

    Ritar, A J; Ball, P D; O'May, P J

    1990-01-01

    The experiments, using a total of 1833 Cashmere does, were conducted to examine the effects on fertility and fecundity of intravaginal treatment for control of ovulation, time of insemination by cervical and laparoscopic methods, semen processing in pellets and straws, and number of frozen-thawed motile spermatozoa. Adult does (greater than or equal to 2.5 years) that had previously kidded were inseminated into the cervix, and maiden (kid: 6-8 months; hogget: 18 months) and adult does were inseminated laparoscopically. The rates of pregnancy determined by ultrasonic scanning (75-80 days after insemination) for cervical (Experiment 1) and laparoscopic (Experiments 2 and 3) insemination were 39.1%, 63.6% and 52.1%. The number of motile spermatozoa did not affect fertility after cervical (80, 120 and 160 x 10(6) or laparoscopic (Experiment 2: 15, 30 and 60 x 10(6); Experiment 3:5, 10 and 20 x 10(6) insemination. The method of insemination or number of motile spermatozoa did not affect fecundity. With cervical insemination, fertility and fecundity improved with increasing depth of insemination into the reproductive tract. Intravaginal sponges containing fluorogestone acetate and controlled internal drug release (CIDR) devices containing progesterone were equally effective for control of ovulation when combined with an injection of pregnant mare's serum gonadotrophin (PMSG; 200 i.u.) before insemination. Fertility was higher when does were inseminated before than after ovulation. After laparoscopic insemination, results were similar for semen frozen as pellets and in straws, and for 3-, 6- and 24-fold pre-freezing dilution of semen. For kid, hogget and adult does in Experiment 3, pregnancy rates were 34.0%, 55.4% and 63.9% and rates of fecundity were 1.17, 1.22 and 1.27 fetuses/pregnant doe.

  3. Implications of intensification of pastoral animal production on animal welfare.

    PubMed

    Stafford, Kj; Gregory, Ng

    2008-12-01

    The intensification of pastoral animal production results from several major developments including increased forage production and utilisation, diet supplementation, breeding animals to increase milk, meat or wool production, and changes in management. The impact of increased intensification on welfare will differ across species and systems. More intensive-grazing systems and the feeding of novel forages will underpin all moves to intensification. More intensive grazing generally reduces opportunities for shade and shelter. Improved nutrition will generally benefit welfare but competition for available feed may cause increased social pressure. Increased flock and herd size will be associated with a reduction in the human:animal ratio and less time to observe individual animals. Remote monitoring of activity and health might counter this impact. Intensification of dairy production will result in larger herds, more year-round milking, robotic milking, use of housing and yards year round, and total mixed-ration feeding. Larger herds mean longer distances to walk to and from the dairy shed, and more lameness and less time to spend on self-maintenance activities such as grooming. Holding and feeding dairy cows on yards will cause an increase in lameness and mastitis and perhaps an increase in agonistic behaviour but will reduce time spent walking. Intensification of sheep production will involve increased flock size, increased fecundity, breeding from hoggets, and breeding ewes all year round. Housing during lambing might be considered appropriate, as would feeding to lift milk yields. Increased fecundity with an increase in triplets will increase lamb mortality rates, but housing ewes, when managed well, will result in reduced lamb mortality. Intensification of lamb finishing will be by improved nutrition. Intensification of beef production will include more breeding of heifers at 15 months, and more problems with dystocia. Intensification of pastoral production will

  4. Towards evenly distributed grazing patterns: including social context in sheep management strategies

    PubMed Central

    Morales, Juan Manuel

    2016-01-01

    Background. A large proportion of natural grasslands around the world is exposed to overgrazing resulting in land degradation and biodiversity loss. Although there is an increasing effort in the promotion of sustainable livestock management, rangeland degradation still occurs because animals’ foraging behaviour is highly selective at different spatial scales. The assessment of the ecological mechanisms modulating the spatial distribution of grazing and how to control it has critical implications for long term conservation of resources and the sustainability of livestock production. Considering the relevance of social interactions on animals’ space use patterns, our aim was to explore the potential effects of including animals’ social context into management strategies using domestic sheep grazing in rangelands as case study. Methods. We used GPS data from 19 Merino sheep (approximately 10% of the flock) grazing on three different paddocks (with sizes from 80 to 1000 Ha) during a year, to estimate resource selection functions of sheep grazing in flocks of different levels of heterogeneity. We assessed the effects of sheep class (i.e., ewes, wethers, and hoggets), age, body condition and time since release on habitat selection patterns. Results. We found that social rank was reflected on sheep habitat use, where dominant individuals (i.e., reproductive females) used more intensively the most preferred areas and low-ranked (i.e., yearlings) used less preferred areas. Our results showed that when sheep grazed on more heterogeneous flocks, grazing patterns were more evenly distributed at all the paddocks considered in this study. On the other hand, when high-ranked individuals were removed from the flock, low-ranked sheep shifted their selection patterns by increasing the use of the most preferred areas and strongly avoided to use less preferred sites (i.e., a highly selective grazing behaviour). Discussion. Although homogenization and segregation of flocks by

  5. Towards evenly distributed grazing patterns: including social context in sheep management strategies.

    PubMed

    di Virgilio, Agustina; Morales, Juan Manuel

    2016-01-01

    Background. A large proportion of natural grasslands around the world is exposed to overgrazing resulting in land degradation and biodiversity loss. Although there is an increasing effort in the promotion of sustainable livestock management, rangeland degradation still occurs because animals' foraging behaviour is highly selective at different spatial scales. The assessment of the ecological mechanisms modulating the spatial distribution of grazing and how to control it has critical implications for long term conservation of resources and the sustainability of livestock production. Considering the relevance of social interactions on animals' space use patterns, our aim was to explore the potential effects of including animals' social context into management strategies using domestic sheep grazing in rangelands as case study. Methods. We used GPS data from 19 Merino sheep (approximately 10% of the flock) grazing on three different paddocks (with sizes from 80 to 1000 Ha) during a year, to estimate resource selection functions of sheep grazing in flocks of different levels of heterogeneity. We assessed the effects of sheep class (i.e., ewes, wethers, and hoggets), age, body condition and time since release on habitat selection patterns. Results. We found that social rank was reflected on sheep habitat use, where dominant individuals (i.e., reproductive females) used more intensively the most preferred areas and low-ranked (i.e., yearlings) used less preferred areas. Our results showed that when sheep grazed on more heterogeneous flocks, grazing patterns were more evenly distributed at all the paddocks considered in this study. On the other hand, when high-ranked individuals were removed from the flock, low-ranked sheep shifted their selection patterns by increasing the use of the most preferred areas and strongly avoided to use less preferred sites (i.e., a highly selective grazing behaviour). Discussion. Although homogenization and segregation of flocks by classes

  6. The effect of ingesting a saltbush and barley ration on the carcass and eating quality of sheepmeat.

    PubMed

    Pearce, K L; Pethick, D W; Masters, D G

    2008-03-01

    Forage halophytes such as saltbush (Atriplex spp.) are widely used to revegetate Australian saline land and can provide a medium-quality fodder source. An animal house experiment was conducted to investigate differences in the carcass and eating quality of sheep ingesting saltbush from saline land in combination with a barley supplement. Twenty-six merino hoggets (two groups of 13) were fed either a 60 : 40 dried saltbush (Atriplex nummularia): barley (S + B) ration or a 33 : 25 : 42 lupins : barley : oaten hay ration (C) for 10 weeks prior to commercial slaughter. After 10 weeks, all sheep were commercially slaughtered and a single loin (from 12th rib to chump) collected from each animal for taste-panel analysis. Carcass weight, total tissue depth over the 12th rib 110 mm from the midline (GR fat depth), ultimate pH and colour were determined and X-ray bone densitometry used to estimate the fat content of the carcass. Blood samples were taken to assess the hormonal response to ingesting these diets and fatty acid profiles of the subcutaneous and intramuscular fat were determined. Both groups grew at the same rate (62 g/day) and had similar hot carcass weights (P > 0.01) (17.2 ± 0.3 kg for S + B and 17.9 ± 0.3 kg for C). However, these live weights may not be high enough to be commercially viable such that saltbush and barley may only be suitable as a maintenance feed. The S + B-fed sheep had a significantly (P = 0.055) lower fat and higher lean content (P < 0.05) than the C group. This is a positive finding as fat denudation is a significant cost to processors and farmers can produce sheep that are depositing less fat or more lean per unit of live-weight gain. The decreased fat and increased lean content were attributed to the higher protein : energy ratio available for production and lower circulating insulin and higher growth hormone of the S + B-fed sheep. The lower body-fat content and lower metabolisable energy and digestible organic matter intake did