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Sample records for curlew numenius americanus

  1. Brood amalgamation in the Bristle-thighed Curlew Numenius tahitiensis: process and function

    USGS Publications Warehouse

    Lanctot, Richard B.; Gill, R.E.; Tibbitts, T.L.; Handel, C.M.

    1995-01-01

    Alloparental care in birds generally involves nonbreeding adults that help at nests or breeding adults that help raise young in communal nests. A less often reported form involves the amalgamation of broods, where one or more adults care for young that are not their own. We observed this phenomenon among Bristle-thighed Curlew Numenius tahitiensis broods in western Alaska during 1990–1992. Amalgamation of broods generally involved the formation of temporary and extended associations. Temporary associations were formed by the incidental convergence of broods soon after they left their nests. During this period, parents defended distinct brood-rearing areas, were antagonistic to conspecifics and remained together for less than 3 days. Extended associations formed when chicks were 1–2 weeks old. Here, parents and their broods occupied distinct, but adjacent, brood-rearing areas and moved around as a unit. Whether a brood participated in either temporary or extended associations or remained solitary appeared to depend on brood density in the immediate area and on hatching date. When chicks were 3–4 weeks old, aggregations of up to ten broods formed wherein young mixed and parents defended a common brood-rearing area. All broods (n = 48) that survived to fledging joined such aggregations. Alloparental care involved only antipredator defence and was not associated with activities such as feeding and brooding. Most female parents abandoned their broods shortly after the young could fly and when aggregations were forming. The female parent of a pair always deserted its young before or on the same day as the male parent and, in every aggregation, one or two males continued to tend young for about 5 days longer than other male parents. In most cases, adults deserted the young 2–6 days before the young departed the area when about 38 days old. Bristle-thighed Curlews also formed temporary associations with American and Pacific Golden Plover Pluvialis dominica and

  2. Nonbreeding eastern curlews Numenius madagascariensis do not increase the rate of intake or digestive efficiency before long-distance migration because of an apparent digestive constraint.

    PubMed

    Zharikov, Yuri; Skilleter, Gregory A

    2003-01-01

    The possibility of premigratory modulation in gastric digestive performance was investigated in a long-distance migrant, the eastern curlew (Numenius madagascariensis), in eastern Australia. The rate of intake in the curlews was limited by the rate of digestion but not by food availability. It was hypothesized that before migration, eastern curlews would meet the increased energy demand by increasing energy consumption. It was predicted that (1) an increase in the rate of intake and the corresponding rate of gastric throughput would occur or (2) the gastric digestive efficiency would increase between the mid-nonbreeding and premigratory periods. Neither crude intake rate (the rate of intake calculated including inactive pauses; 0.22 g DM [grams dry mass] or 3.09 kJ min(-1)) nor the rate of gastric throughput (0.15 g DM or 2.85 kJ min(-1)) changed over time. Gastric digestive efficiency did not improve between the periods (91%) nor did the estimated overall energy assimilation efficiency (63% and 58%, respectively). It was concluded that the crustacean-dominated diet of the birds is processed at its highest rate and efficiency throughout a season. It appears that without a qualitative shift in diet, no increase in intake rate is possible. Accepting these findings at their face value poses the question of how and over what time period the eastern curlews store the nutrients necessary for the ensuing long, northward nonstop flight.

  3. Coelomic implantation of satellite transmitters in the bar-tailed godwit (Limosa lapponica) and the bristle-thighed curlew (Numenius tahitiensis) using propofol, bupivacaine, and lidocaine

    USGS Publications Warehouse

    Mulcahy, Daniel M.; Gartrell, Brett D.; Gill, Robert E.; Tibbitts, T. Lee; Ruthrauff, Daniel R.

    2011-01-01

    Intravenous propofol was used as a general anesthetic with a 2∶1 (mg∶mg) adjunctive mixture of lidocaine and bupivacaine as local anesthetics infiltrated into the surgical sites for implantation of satellite transmitters into the right abdominal air sac of 39 female and 4 male bar-tailed godwits (Limosa lapponica baueri and Limosa lapponica menzbeiri) and 11 female and 12 male bristle-thighed curlews (Numenius tahitiensis). The birds were captured on nesting grounds in Alaska, USA, and on overwintering areas in New Zealand and Australia from 2005 through 2008. As it was developed, the mass of the transmitter used changed yearly from a low of 22.4 ± 0.2 g to a high of 27.1 ± 0.2 g and weighed 25.1 ± 0.2 g in the final year. The mean load ratios ranged from 5.2% to 7.7% for godwits and from 5.7% to 7.5% for curlews and exceeded 5% for all years, locations, and genders of both species. The maximum load ratio was 8.3% for a female bar-tailed godwit implanted in Australia in 2008. Three godwits and no curlews died during surgery. Most birds were hyperthermic upon induction but improved during surgery. Two godwits (one in New Zealand and one in Australia) could not stand upon release, likely due to capture myopathy. These birds failed to respond to treatment and were euthanized. The implanted transmitters were used to follow godwits through their southern and northern migrations, and curlews were followed on their southern migration.

  4. Coelomic implantation of satellite transmitters in the bar-tailed godwit (Limosa lapponica) and the bristle-thighed curlew (Numenius tahitiensis) using propofol, bupivacaine, and lidocaine.

    PubMed

    Mulcahy, Daniel M; Gartrell, Brett; Gill, Robert E; Tibbitts, T Lee; Ruthrauff, Daniel R

    2011-03-01

    Intravenous propofol was used as a general anesthetic with a 2:1 (mg:mg) adjunctive mixture of lidocaine and bupivacaine as local anesthetics infiltrated into the surgical sites for implantation of satellite transmitters into the right abdominal air sac of 39 female and 4 male bar-tailed godwits (Limosa lapponica baueri and Limosa lapponica menzbeiri and 11 female and 12 male bristle-thighed curlews (Numenius tahitiensis). The birds were captured on nesting grounds in Alaska, USA, and on overwintering areas in New Zealand and Australia from 2005 through 2008. As it was developed, the mass of the transmitter used changed yearly from a low of 22.4 +/- 0.2 g to a high of 27.1 +/- 0.2 g and weighed 25.1 +/- 0.2 g in the final year. The mean load ratios ranged from 5.2% to 7.7% for godwits and from 5.7% to 7.5% for curlews and exceeded 5% for all years, locations, and genders of both species. The maximum load ratio was 8.3% for a female bar-tailed godwit implanted in Australia in 2008. Three godwits and no curlews died during surgery. Most birds were hyperthermic upon induction but improved during surgery. Two godwits (one in New Zealand and one in Australia) could not stand upon release, likely due to capture myopathy. These birds failed to respond to treatment and were euthanized. The implanted transmitters were used to follow godwits through their southern and northern migrations, and curlews were followed on their southern migration.

  5. 1993 study of long-billed curlews on the Yakima Training Center

    SciTech Connect

    Hand, K.D.; Cadwell, L.L.

    1994-04-01

    Pacific Northwest Laboratory conducted a study for the US Department of the Army on long-billed curlews (Numenius americanus) on the Yakima Training Center (YTC) in the spring and summer of 1993. Long-billed curlews are a Class IIIc federal candidate species and are listed as a ``species of special concern`` by the Washington Department of Wildlife. The objectives of this study were to (1) locate major nesting areas, (2) locate brood rearing areas, (3) evaluate habitat requirements, (4) determine diet, (5) evaluate response to troop activities, (6) estimate population size, (7) estimate recruitment rates, and (8) establish a relative abundance survey method.

  6. Evaluation of capture techniques for long-billed curlews wintering in Texas

    USGS Publications Warehouse

    Woodin, Marc C.; Skoruppa, Mary K.; Edwardson, Jeremy W.; Austin, Jane E.

    2012-01-01

    Texas coast harbors the largest, eastern-most populations of Long-billed Curlews (Numenius americanus) in North America; however, very little is known about their migration and wintering ecology. Curlews are readily captured on their breeding grounds, but experience with capturing the species during the non-breeding season is extremely limited. We assessed the efficacy of 6 capture techniques for Long-billed Curlews in winter: 1) modified noose ropes, 2) remotely controlled bow net, 3) Coda Netgun, 4) Super Talon net gun, 5) Hawkseye whoosh net, and 6) cast net. The Coda Netgun had the highest rate of captures per unit of effort (CPUE = 0.31; 4 curlew captures/13 d of trapping effort), followed by bow net (CPUE = 0.17; 1 capture/6 d of effort), whoosh net (CPUE = 0.14; 1 capturel7 d of effort), and noose ropes (CPUE = 0.07; 1 capturel15 d of effort). No curlews were captured using the Super Talon net gun or a cast net (3 d and 1 d of effort, respectively). Multiple capture techniques should be readily available for maximum flexibility in matching capture methods with neophobic curlews that often unpredictably change referred feeding locations among extremely different habitat types.

  7. Long-billed curlews on the Yakima Training Center: Information for base realignment

    SciTech Connect

    Hand, K.D.; Cadwell, L.L.; Eberhardt, L.E.

    1994-02-01

    This report summarizes and discusses the results obtained during 1992 from the study of long-billed curlews on the Yakima Training Center (YTC), which Pacific Northwest Laboratory conducted for the US Department of the Army. This study was initiated to provide basic ecological information on YTC long-billed curlews (Numenius americanus). The long-billed curlew is a relatively common spring and summer resident on the YTC. However, other than casual observations, very little is known about the distribution, density, reproductive success, and habitat requirements for this species on the YTC. Until recently the long-billed curlew was a US Fish and Wildlife Service candidate for listing as threatened or endangered; however, on November 21, 1991 it was down-listed to Class IIIc. The Washington Department of Wildlife lists the long-billed curlew as a ``species of special concern.`` Specific objectives of this study were to (1) locate nesting areas, (2) locate brood-rearing areas, (3) evaluate habitat requirements, (4) determine diet, (5) evaluate response to troop activities, (6) evaluate the impact of livestock grazing, (7) estimate the population size, and (8) estimate recruitment rates. Six curlews (four females and two males) were captured and fitted with radio transmitters. These birds were relocated to obtain nesting, habitat use, and feeding information. Road surveys conducted over most of the YTC provided information on the bird`s general distribution, habitat requirements, and nesting and brood-rearing areas.

  8. Estimating the breeding population of long-billed curlew in the United States

    USGS Publications Warehouse

    Stanley, T.R.; Skagen, S.K.

    2007-01-01

    Determining population size and long-term trends in population size for species of high concern is a priority of international, national, and regional conservation plans. Long-billed curlews (Numenius americanus) are a species of special concern in North America due to apparent declines in their population. Because long-billed curlews are not adequately monitored by existing programs, we undertook a 2-year study with the goals of 1) determining present long-billed curlew distribution and breeding population size in the United States and 2) providing recommendations for a long-term long-billed curlew monitoring protocol. We selected a stratified random sample of survey routes in 16 western states for sampling in 2004 and 2005, and we analyzed count data from these routes to estimate detection probabilities and abundance. In addition, we evaluated habitat along roadsides to determine how well roadsides represented habitat throughout the sampling units. We estimated there were 164,515 (SE = 42,047) breeding long-billed curlews in 2004, and 109,533 (SE = 31,060) breeding individuals in 2005. These estimates far exceed currently accepted estimates based on expert opinion. We found that habitat along roadsides was representative of long-billed curlew habitat in general. We make recommendations for improving sampling methodology, and we present power curves to provide guidance on minimum sample sizes required to detect trends in abundance.

  9. Spatial genetic structure of bristle-thighed curlews (Numenius tahitiensis): breeding area differentiation not reflected on the non-breeding grounds

    USGS Publications Warehouse

    Sonsthagen, Sarah A.; Tibbitts, T. Lee; Gill, Robert E.; Williams, Ian S.; Talbot, Sandra L.

    2015-01-01

    Migratory birds occupy geographically and ecologically disparate areas during their annual cycle with conditions on breeding and non-breeding grounds playing separate and important roles in population dynamics. We used data from nuclear microsatellite and mitochondrial DNA control region loci to assess the breeding and non-breeding spatial genetic structure of a transoceanic migrant shorebird, the bristle-thighed curlew. We found spatial variance in the distribution of allelic and haplotypic frequencies between the curlew's two breeding areas in Alaska but did not observe this spatial structure throughout its non-breeding range on low-lying tropical and subtropical islands in the Central Pacific (Oceania). This suggests that the two breeding populations do not spatially segregate during the non-breeding season. Lack of migratory connectivity is likely attributable to the species' behavior, as bristle-thighed curlews exhibit differential timing of migration and some individuals move among islands during non-breeding months. Given the detrimental impact of many past and current human activities on island ecosystems, admixture of breeding populations in Oceania may render the bristle-thighed curlew less vulnerable to perturbations there, as neither breeding population will be disproportionally affected by local habitat losses or by stochastic events. Furthermore, lack of migratory connectivity may enable bristle-thighed curlews to respond to changing island ecosystems by altering their non-breeding distribution. However, availability of suitable non-breeding habitat for curlews in Oceania is increasingly limited on both low-lying and high islands by habitat loss, sea level rise, and invasive mammalian predators that pose a threat to flightless and flight-compromised curlews during the molting period.

  10. Annual migratory patterns of long-billed curlews in the American west

    USGS Publications Warehouse

    Page, Gary W.; Warnock, Nils; Tibbitts, T. Lee; Jorgensen, Dennis; Hartman, C. Alex; Stenzel, Lynne E.

    2014-01-01

    Effective conservation of migratory species requires comprehensive knowledge of annual movement patterns. Such information is sparse for the Long-billed Curlew (Numenius americanus), a North American endemic shorebird of conservation concern. To test hypotheses about individual and area differences in migratory patterns across western North America, we tagged 29 curlews with satellite transmitters at breeding sites in Oregon, Nevada, and Montana. Transmissions from 28 birds for up to 4 years demonstrated that all wintered within the species’ known winter range, including 9 from Oregon tracked to agricultural areas of California’s Central Valley; 5 from Nevada tracked to the Central Valley, northern Gulf of California, or west coast of Baja California, Mexico; and 14 from Montana that wintered inland, from the Texas Panhandle south to the Mexican Plateau, or near the Gulf of Mexico. Montana breeders migrated east of the Rocky Mountains and traveled more than twice the distance of Oregon and Nevada breeders. Montana birds also stopped more often and longer during most passages. As a group, curlews arrived on their Oregon breeding grounds earlier than in Montana, while males preceded females in Montana and possibly Oregon. No consistent pattern emerged between sexes in departure from breeding areas, although within pairs males departed later than their mates. Individuals exhibited strong fidelity to breeding and wintering sites, and many birds showed a strong propensity for agricultural regions during winter. Our results underscore the importance of studying

  11. Long-Billed Curlew Breeding Success on Mid-Columbia River National Wildlife Refuges, South-Central Washington and North-Central Oregon, 2007-08

    USGS Publications Warehouse

    Stocking, Jessica; Elliott-Smith, Elise; Holcomb, Neil; Haig, Susan M.

    2010-01-01

    Long-billed curlew (Numenius americanus) reproductive success was evaluated on the Mid-Columbia River National Wildlife Refuges of south-central Washington and north-central Oregon during the 2007 and 2008 breeding seasons. Additionally, we assisted the U.S. Fish and Wildlife Service in collecting information on distribution, abundance, and brood habitat for this shorebird species of conservation concern. A total of 32 breeding pairs were located on the refuges in 2007 and 35 pairs were located in 2008. We monitored 17 nests in 2007 and 23 nests in 2008. Curlew pairs were most abundant on Hanford Reach National Monument in 2007 but more nests were located on Umatilla National Wildlife Refuge in both years, with Columbia National Wildlife Refuge supporting few pairs. Nest success was 23.6 percent in 2007 and 32.9 percent in 2008 after taking into account exposure time and combining data for all the refuges. We were unable to detect any relationship between nest success and habitat type or habitat variables measured. However, our study was the first to document use of agricultural fields on the refuge as curlew nest habitat. We collected 39 and 28 brood locations in 2007 and 2008, respectively, and many observations were likely resightings of the same brood. Broods used a similar variety of habitats as nesting curlew and no clear habitat use pattern was detected.

  12. Notes on longevity and flightlessness in bristle-thighed curlews

    USGS Publications Warehouse

    Marks, J.S.; Redmond, R.L.; Hendricks, P.; Clapp, R.B.; Gill, R.E.

    1990-01-01

    Bristle-thighed Curlews (Numenius tahitiensis) are among the least-studied shorebirds in the world. They have a highly restricted breeding range in western Alaska and winter exclusively on remote islands in the central and south Pacific (AOU 1983, Kessel 1989). The status of these birds is not known, but they are considered to be rare throughout their range (Johnsgard 1981). We describe two unusual traits of Bristle-thighed Curlews - exceptional longevity and flightlessness during molt-and discuss their significance to the species' migration and nonbreeding ecology.

  13. Antipredator strategies in breeding Bristle-thighed Curlews

    USGS Publications Warehouse

    McCaffery, Brian J.; Gill, Robert E.

    1992-01-01

    Each fall the world’s breeding population of Bristle-thighed Curlews (Numenius tahitiensis) arrives on the central Pacific wintering grounds following a migration that entails a non- stop flight of over 5000 kilometers. Sun-drenched, palm-shrouded atolls will be their home for the ensuing eight months. Even in the avian world, however, such apparant luxury is not without costs. For the Bristle-thighed Curlew these costs are incurred on the breeding grounds. From the time they arrive there in early May until they depart again for the wintering grounds in August and September, curlews are exposed to a host of predators. Gyrfalcons (Falco rusticolus), Golden Eagles (Aquila chrysaetos), Rough-legged Hawks (Buteo lagopus), Northern Harriers (Circus cyaneus), Parasitic Jaegers (Stercorarius parasiticus), Short-eared Owls (Asio flammeus), Common Ravens (Corvus corax) and Red Foxes (Vulpes vulpes) are potential predators of curlews and their offspring. To combat these threats, the Bristle-thighed Curlew has evolved an elaborate suite of antipredator defenses. Depending on the threat and the phase of the breeding cycle, Bristle-thighed Curlews may respond to potential predators by fleeing or flocking, by camouflage or combat. Given the variety of predators on the tundra, a variety of options is critical.

  14. Seasonal occurrence of migrant whimbrels and bristle-thighed curlews on the Yukon-Kuskokwim Delta, Alaska

    USGS Publications Warehouse

    Handel, Colleen M.; Dau, Christian P.

    1988-01-01

    Migrant Whimbrels (Numenius phaeopus) and Bristle-thighed Curlews (N. tahitiensis) were recorded during five summers along coastal tundra of the Yukon-Kuskokwim Delta, Alaska. From June to September, 1975-1979, 358 flocks totalling 1,265 curlews were observed; an additional 54 flocks were identified by vocalization alone. Among the 359 flocks identified to species, 52% were of Whimbrels, 47% were of Bristle-thighed Curlews, and 1% were of both species. Flocks as large as 48 Whimbrels and 33 Bristle-thighed Curlews were recorded, but 87% of the flocks contained five or fewer birds. During 2 years with early springs a few Whimbrels and Bristle-thighed Curlews were recorded on the delta in early June; these may have been late spring migrants, oversummering nonbreeders, or very early failed breeders. Whimbrel numbers peaked twice each summer, first in middle to late July and again in late August. These peaks probably consisted mainly of late failed breeders and of successful breeders with juveniles, respectively. The patterns of occurrence of Bristle-thighed Curlews were more complex, with up to three peaks in abundance each season, probably consisting of the following populational subclasses: (1) early failed breeders from late June to mid-July, (2) late failed breeders in late July, and (3) successful breeders and juveniles in early August. Most Bristle-thighed Curlews were gone by mid-August and Whimbrels, by early September. For both species the earliest juveniles were seen in late July in flocks with adults. The Yukon-Kuskokwim Delta is conservatively estimated to support several thousands of both Whimbrels and Bristle-thighed Curlews. This area is considered to be particularly important for Bristle-thighed Curlews because it is the primary of only two known areas used during migration between their nesting grounds in Alaska and the first known stop on their wintering grounds in the Hawaiian Island chain, a transoceanic distance of 3,800 km. Whimbrels are more

  15. Oswaldotrema nacinovici gen. nov. sp. nov. (Digenea: Philophthalmidae) from Numenius phaeopus (Aves: Scolopacidae) in Brazil.

    PubMed

    Muniz-Pereira, L C; Pinto, R M

    2000-01-01

    A new genus, Oswaldotrema gen. nov. is proposed. Oswaldotrema nacinovici sp. nov. is descibed from Numenius phaeopus Latham, 1790. Differentiation from the other related genera, namely Philophthalmus, Pygorchis, Proctobium, Parorchis, Echinostephila, Cloacitrema, Pittacium, Ophthalmotrema, Skrjabinovermis and Paratrema, was based on morphological characters, mainly on those referring to the body surface, body shape, head, esophagus, pharynx, acetabulum, vitellaria, vitelline reservoir and seminal vesicle.

  16. Preliminary investigations of the winter ecology of Long-billed Curlews in coastal Texas

    USGS Publications Warehouse

    Woodin, Marc C.; Skoruppa, Mary Kay; Edwardson, Jeremy W.; Austin, Jane E.

    2012-01-01

    Results from this 1-year pilot study yielded an intriguing combination of findings that warrant further investigation. Observations include reduced numbers of roosting birds along the Texas coast during dry conditions, highly dynamic use of nocturnal roost sites, use of widely divergent habitat types for foraging, low body mass of most captured birds, and apparent fidelity to general feeding areas. Future investigations of this eastern winter population of curlews would benefit from larger sample sizes and monitoring of individual birds.

  17. Building development and roads: implications for the distribution of stone curlews across the Brecks.

    PubMed

    Clarke, Ralph T; Liley, Durwyn; Sharp, Joanna M; Green, Rhys E

    2013-01-01

    Substantial new housing and infrastructure development planned within England has the potential to conflict with the nature conservation interests of protected sites. The Breckland area of eastern England (the Brecks) is designated as a Special Protection Area for a number of bird species, including the stone curlew (for which it holds more than 60% of the UK total population). We explore the effect of buildings and roads on the spatial distribution of stone curlew nests across the Brecks in order to inform strategic development plans to avoid adverse effects on such European protected sites. Using data across all years (and subsets of years) over the period 1988-2006 but restricted to habitat areas of arable land with suitable soils, we assessed nest density in relation to the distances to nearest settlements and to major roads. Measures of the local density of nearby buildings, roads and traffic levels were assessed using normal kernel distance-weighting functions. Quasi-Poisson generalised linear mixed models allowing for spatial auto-correlation were fitted. Significantly lower densities of stone curlew nests were found at distances up to 1500m from settlements, and distances up to 1000m or more from major (trunk) roads. The best fitting models involved optimally distance-weighted variables for the extent of nearby buildings and the trunk road traffic levels. The results and predictions from this study of past data suggests there is cause for concern that future housing development and associated road infrastructure within the Breckland area could have negative impacts on the nesting stone curlew population. Given the strict legal protection afforded to the SPA the planning and conservation bodies have subsequently agreed precautionary restrictions on building development within the distances identified and used the modelling predictions to agree mitigation measures for proposed trunk road developments.

  18. Building Development and Roads: Implications for the Distribution of Stone Curlews across the Brecks

    PubMed Central

    Clarke, Ralph T.; Liley, Durwyn; Sharp, Joanna M.; Green, Rhys E.

    2013-01-01

    Background Substantial new housing and infrastructure development planned within England has the potential to conflict with the nature conservation interests of protected sites. The Breckland area of eastern England (the Brecks) is designated as a Special Protection Area for a number of bird species, including the stone curlew (for which it holds more than 60% of the UK total population). We explore the effect of buildings and roads on the spatial distribution of stone curlew nests across the Brecks in order to inform strategic development plans to avoid adverse effects on such European protected sites. Methodology Using data across all years (and subsets of years) over the period 1988-2006 but restricted to habitat areas of arable land with suitable soils, we assessed nest density in relation to the distances to nearest settlements and to major roads. Measures of the local density of nearby buildings, roads and traffic levels were assessed using normal kernel distance-weighting functions. Quasi-Poisson generalised linear mixed models allowing for spatial auto-correlation were fitted. Results Significantly lower densities of stone curlew nests were found at distances up to 1500m from settlements, and distances up to 1000m or more from major (trunk) roads. The best fitting models involved optimally distance-weighted variables for the extent of nearby buildings and the trunk road traffic levels. Significance The results and predictions from this study of past data suggests there is cause for concern that future housing development and associated road infrastructure within the Breckland area could have negative impacts on the nesting stone curlew population. Given the strict legal protection afforded to the SPA the planning and conservation bodies have subsequently agreed precautionary restrictions on building development within the distances identified and used the modelling predictions to agree mitigation measures for proposed trunk road developments. PMID:24023662

  19. Distribution, numbers, and habitat of Bristle-thighed Curlews (Numinous tahitiensis) on Rangiroa atoll

    USGS Publications Warehouse

    Gill, Robert E.; Redmond, Roland L.

    1992-01-01

    We assessed the numbers, distribution, and habitat of Bristle-tithed Curlews (Numinous tahitiensis) on Rangiroa Atoll, Tuamotu Archipelago, during a visit in April 1988. We estimated a total of 250-350 curlews on the atoll. These birds were seen only on the southern and western rims, where they were most common on (1) saltpans within clusters of small islets and (2) narrow channels between islets that were bordered by shrubs and herb mats. The distribution of curlews on Rangiroa appeared to be determined by the distribution of humans and their commensal animals and by the availability of habitats. Given the species' relatively low numbers, low reproductive rate, and prebasic moult which, for some adults, entails a flightless period, conservation and management efforts must begin on the non-breeding grounds. These efforts should focus on reducing or eliminating potential mortality factors such as subsistence harvest, introduced predators, and contaminants. Countries throughout the species' non-breeding range are encouraged to be active in these efforts.

  20. An outbreak of cryptosporidiosis in a collection of Stone curlews (Burhinus oedicnemus) in Dubai.

    PubMed

    Zylan, Kasamyra; Bailey, Tom; Smith, Huw V; Silvanose, Christudas; Kinne, Joerg; Schuster, Rolf K; Hyland, Kevin

    2008-10-01

    We describe an outbreak of cryptosporidiosis in Stone curlews kept in a mixed-species rearing unit in Dubai. Cryptosporidium was the predominant intestinal pathogen detected, although microbiological investigations revealed a concurrent Salmonella infantis infection in two of the 29 Stone curlew chicks that died. Nineteen of 29 birds had catarrhal enteritis associated with histopathological findings of numerous Cryptosporidium developmental stages at the mucosal surface. Catarrhal enteritis was present without associated Cryptosporidium oocysts in five cases. Histology of the intestine, faecal examination by direct microscopy and antigenic detection by immunochromatography revealed the presence of Cryptosporidium spp. associated with catarrhal enteritis in intestinal sections and faeces. Clinical and histopathological outcomes of infection were severe, including disruption of intestinal epithelial integrity, the presence of numerous endogenous Cryptosporidium stages in intestinal epithelia and the excretion of large numbers of sporulated oocysts. The application of polymerase chain reaction and restriction fragment length polymorphism techniques at two 18S rRNA and one Cryptosporidium oocyst wall protein gene locus confirmed the presence of Cryptosporidium parvum DNA in faecal samples.

  1. CHARACTERIZATION OF MICROSATELLITE LOCI IN SCHOENOPLECTUS AMERICANUS (CYPERACEAE)

    EPA Science Inventory

    Schoenoplectus americanus is a model organism for studying ecological and ecosystem responses of salt marsh plant communities to global climate change. Here we characterize 16 microsatellite loci in S. americanus to facilitate studies on the genetic basis of phenotypic responses...

  2. Genome of the human hookworm Necator americanus.

    PubMed

    Tang, Yat T; Gao, Xin; Rosa, Bruce A; Abubucker, Sahar; Hallsworth-Pepin, Kymberlie; Martin, John; Tyagi, Rahul; Heizer, Esley; Zhang, Xu; Bhonagiri-Palsikar, Veena; Minx, Patrick; Warren, Wesley C; Wang, Qi; Zhan, Bin; Hotez, Peter J; Sternberg, Paul W; Dougall, Annette; Gaze, Soraya Torres; Mulvenna, Jason; Sotillo, Javier; Ranganathan, Shoba; Rabelo, Elida M; Wilson, Richard K; Felgner, Philip L; Bethony, Jeffrey; Hawdon, John M; Gasser, Robin B; Loukas, Alex; Mitreva, Makedonka

    2014-03-01

    The hookworm Necator americanus is the predominant soil-transmitted human parasite. Adult worms feed on blood in the small intestine, causing iron-deficiency anemia, malnutrition, growth and development stunting in children, and severe morbidity and mortality during pregnancy in women. We report sequencing and assembly of the N. americanus genome (244 Mb, 19,151 genes). Characterization of this first hookworm genome sequence identified genes orchestrating the hookworm's invasion of the human host, genes involved in blood feeding and development, and genes encoding proteins that represent new potential drug targets against hookworms. N. americanus has undergone a considerable and unique expansion of immunomodulator proteins, some of which we highlight as potential treatments against inflammatory diseases. We also used a protein microarray to demonstrate a postgenomic application of the hookworm genome sequence. This genome provides an invaluable resource to boost ongoing efforts toward fundamental and applied postgenomic research, including the development of new methods to control hookworm and human immunological diseases.

  3. Genome of the human hookworm Necator americanus

    PubMed Central

    Abubucker, Sahar; Hallsworth-Pepin, Kymberlie; Martin, John; Tyagi, Rahul; Heizer, Esley; Zhang, Xu; Bhonagiri-Palsikar, Veena; Minx, Patrick; Warren, Wesley C.; Wang, Qi; Zhan, Bin; Hotez, Peter J.; Sternberg, Paul W.; Dougall, Annette; Gaze, Soraya Torres; Mulvenna, Jason; Sotillo, Javier; Ranganathan, Shoba; Rabelo, Elida M.; Wilson, Richard W.; Felgner, Philip L.; Bethony, Jeffrey; Hawdon, John M.; Gasser, Robin B.; Loukas, Alex; Mitreva, Makedonka

    2014-01-01

    The hookworm Necator americanus is the predominant soil-transmitted human parasite. Adult worms feed on blood in the small intestine, causing iron deficiency anaemia, malnutrition, growth and development stunting in children, and severe morbidity and mortality during pregnancy in women. Characterization of the first hookworm genome sequence (244 Mb, 19,151 genes) identified genes orchestrating the hookworm's invasion of the human host, genes involved in blood feeding and development, and genes encoding proteins that represent new potential drug targets against hookworms. N. americanus has undergone a considerable and unique expansion of immunomodulator proteins, some of which we highlight as potential novel treatments against inflammatory diseases. We also utilize a protein microarray to demonstrate a post-genomic application of the hookworm genome sequence. This genome provides an invaluable resource to boost ongoing efforts towards fundamental and applied post-genomic research, including the development of new methods to control hookworm and human immunological diseases. PMID:24441737

  4. Biomarker analysis of American toad (Anaxyrus americanus) ...

    EPA Pesticide Factsheets

    The objective of the current study was to use a biomarker-based approach to investigate the influence of atrazine exposure on American toad (Anaxyrus americanus) and grey tree frog (Hyla versicolor) tadpoles. Atrazine is one of the most frequently detected herbicides in environmental matrices throughout the United States. In surface waters, it has been found at concentrations from 0.04–2859 μg/L and thus presents a likely exposure scenario for non-target species such as amphibians. Studies have examined the effect of atrazine on the metamorphic parameters of amphibians, however, the data are often contradictory. Gosner stage 22–24 tadpoles were exposed to 0 (control), 10, 50, 250 or 1250 μg/L of atrazine for 48 h. Endogenous polar metabolites were extracted and analyzed using gas chromatography coupled with mass spectrometry. Statistical analyses of the acquired spectra with machine learning classification models demonstrated identifiable changes in the metabolomic profiles between exposed and control tadpoles. Support vector machine models with recursive feature elimination created a more efficient, non-parametric data analysis and increased interpretability of metabolomic profiles. Biochemical fluxes observed in the exposed groups of both A. americanus and H. versicolor displayed perturbations in a number of classes of biological macromolecules including fatty acids, amino acids, purine nucleosides, pyrimidines, and mono- and di-saccharides. Metabolomic

  5. Biomarker analysis of American toad (Anaxyrus americanus) ...

    EPA Pesticide Factsheets

    The objective of the current study was to use a biomarker-based approach to investigate the influence of atrazine exposure on American toad (Anaxyrus americanus) and grey tree frog (Hyla versicolor) tadpoles. Atrazine is one of the most frequently detected herbicides in environmental matrices throughout the United States. In surface waters, it has been found at concentrations from 0.04–2859 μg/L and thus presents a likely exposure scenario for non-target species such as amphibians. Studies have examined the effect of atrazine on the metamorphic parameters of amphibians, however, the data are often contradictory. Gosner stage 22–24 tadpoles were exposed to 0 (control), 10, 50, 250 or 1250 μg/L of atrazine for 48 h. Endogenous polar metabolites were extracted and analyzed using gas chromatography coupled with mass spectrometry. Statistical analyses of the acquired spectra with machine learning classification models demonstrated identifiable changes in the metabolomic profiles between exposed and control tadpoles. Support vector machine models with recursive feature elimination created a more efficient, non-parametric data analysis and increased interpretability of metabolomic profiles. Biochemical fluxes observed in the exposed groups of both A. americanus and H. versicolor displayed perturbations in a number of classes of biological macromolecules including fatty acids, amino acids, purine nucleosides, pyrimidines, and mono- and di-saccharides. Metabolomic

  6. Reproductive Behavior of Echinothrips americanus (Thysanoptera: Thripidae)

    PubMed Central

    Krueger, Stephanie; Jilge, Marcus; Mound, Laurence

    2017-01-01

    Most Thysanoptera possess a haplo-diploid reproductive mode and reproduce via arrhenotoky. Females can mature eggs successively throughout almost their entire life, but in most terebrantian thrips spermiogenesis is complete by adult male eclosion, and testes contain only mature spermatids. In parasitoid wasps this phenomenon of preadult spermiogenesis is described as prospermatogeny. It is unclear if prospermatogeny and this predetermined sperm quantity have implications for mating strategy and fitness. In this study, we give a detailed description of mating behavior of the thripine species Echinothrips americanus, which largely corresponds with the only available data of another species of this family, Frankliniella occidentalis (Thysanoptera: Thripidae). With investigations using light microscopy, we describe for the first time the chronological sequence of internal processes during copulation. The release of male accessory gland material followed subsequently by spermatozoa indicates production of a female-determined type 1 spermatophore. Despite prospermatogeny, males are able to inseminate 10 females with an equal amount of spermatozoa. It is only the quantity of glandular material that decreases with the number of previous copulations. Based on these new findings, the reproductive strategy of this species is discussed.

  7. Homarus Americanus Stomatogastric Nervous System Dissection

    PubMed Central

    Tobin, Anne-Elise; Bierman, Hilary S.

    2009-01-01

    With the goal of understanding how nervous systems produce activity and respond to the environment, neuroscientists turn to model systems that exhibit the activity of interest and are accessible and amenable to experimental methods. The stomatogastric nervous system (STNS) of the American lobster (Homarus americanus; also know was the Atlantic or Maine lobster) has been established as a model system for studying rhythm generating networks and neuromodulation of networks. The STNS consists of 3 anterior ganglia (2 commissural ganglia and an oesophageal ganglion), containing modulatory neurons that project centrally to the stomatogastric ganglion (STG). The STG contains approximately 30 neurons that comprise two central pattern generating networks, the pyloric and gastric networks that underlie feeding behaviors in crustaceans1,2. While it is possible to study this system in vivo3, the STNS continues to produce its rhythmic activity when isolated in vitro. Physical isolation of the STNS in a dish allows for easy access to the somata in the ganglia for intracellular electrophysiological recordings and to the nerves of the STNS for extracellular recordings. Isolating the STNS is a two-part process. The first part, dissecting the stomach from the animal, is described in an accompanying video article4. In this video article, fine dissection techniques are used to isolate the STNS from the stomach. This procedure results in a nervous system preparation that is available for electrophysiological recordings. PMID:19483669

  8. Trichinella surveillance in black bears (Ursus americanus) from Oregon, USA.

    PubMed

    Mortenson, J A; Kent, M L; Fowler, D R; Chomel, B B; Immell, D A

    2014-01-01

    We used serology and muscle digestion to test black bears (Ursus americanus) from western Oregon, USA, for Trichinella. Results indicate black bears in Oregon are not part of a sylvatic cycle for Trichinella, and risk of human exposure to Trichinella larvae from eating black bear meat from Oregon appears low.

  9. Sarcocystis oreamni n. sp. from the mountain goat (oreamnos americanus)

    USDA-ARS?s Scientific Manuscript database

    Numerous species of Sarcocystis have been reported from wild ruminants but none has been named from the Rocky Mountain goat (Oreamnos americanus). Mature sarcocysts were found in frozen muscle samples of 3 of 7 mountain goats from Alaska, USA. Two morphological types of sarcocysts were found; 1 had ...

  10. Eastern equine encephalitis in moose (Alces americanus) in northeastern Vermont.

    PubMed

    Mutebi, John-Paul; Swope, Bethany N; Saxton-Shaw, Kali D; Graham, Alan C; Turmel, Jon P; Berl, Erica

    2012-10-01

    During fall 2010, 21 moose (Alces americanus) sera collected in northeastern Vermont were screened for eastern equine encephalitis virus (EEEV) antibodies using plaque reduction neutralization tests. Six (29%) were antibody positive. This is the first evidence of EEEV activity in Vermont, and the second report of EEEV antibodies in moose.

  11. Safety of florfenicol in the adult lobster (Homarus americanus).

    PubMed

    Basti, David; Bouchard, Deborah; Lichtenwalner, Anne

    2011-03-01

    Aerococcus viridans, the causative agent of the disease gaffkemia, was a major cause of mortality in lobsters (Homarus americanus) held in tidal impoundments during the 1970s and 1980s. Despite reports of an increase in the mortality of lobsters during impoundment, and the widespread prophylactic use of oxytetracycline against A. viridans, this bacterium has not been detected in active disease surveillance of the Maine postcapture lobster population. However, Photobacterium indicum may be an emerging opportunistic pathogen of stressed lobsters. An acute toxicity trial was conducted as a rapid screening procedure for the potential future use of the antibiotic florfenicol. Based on the results of this experiment, florfenicol appears to be well tolerated in adult H. americanus by intrapericardial injection at the 10-100 mg/kg dose. Oxytetracycline dihydrate is contraindicated by intrapericardial injection at the 10-100 mg/kg dose.

  12. Biology and management of Longidorus americanus in a southern USA nursery

    Treesearch

    M.M. Cram; S.W. Fraedrich

    2007-01-01

    A recently discovered nematode, Longidorus americanus, caused stunting of Pinus taeda seedlings at a forest-tree nursery in Georgia, USA. In growth chamber experiments, L. americanus significantly reduced the root size of I? taeda and P elliottii seedlings. Although the root systems of L. palustris...

  13. Muscular Sarcocystis infection in a bear (Ursus americanus).

    PubMed

    Dubey, J P; Topper, M J; Nutter, F B

    1998-04-01

    Sarcocysts of an unidentified Sarcocystis species were found in sections of skeletal muscles of a black bear (Ursus americanus) from North Carolina. Two sarcocysts in a section measured 45 x 37.5 microm and 67.5 x 50 microm and had a thin (<2 microm) sarcocyst wall. The villar protrusions on the cyst wall were up to 2 microm long and up to 0.7 microm wide. The bradyzoites were approximately 6 X 2.5 microm in size. This is the first report of muscular Sarcocystis in a bear.

  14. Migrations and growth of deep-sea lobsters, Homarus americanus.

    PubMed

    Cooper, R A; Uzmann, J R

    1971-01-22

    In distinct contrast to the restricted movements of coastal stocks of lobsters (Homarus americanus), those inhabiting the outer continental shelf undertake extensive seasonal migrations. Of 5710 tagged lobsters released on the outer continental shelf off New England from April 1968 to June 1969, 400 had been recaptured by April 1970. The distribution of the recoveries demonstrated shoalward migration in spring and summer and a return to the edge of the shelf in fall and winter. Deep-sea lobsters have a faster rate of growth than coastal lobsters; growth increments at molting and the frequency of molting are greater.

  15. Hookworm (Necator americanus) larval enzymes disrupt human vascular endothelium.

    PubMed

    Souadkia, Nahed; Brown, Alan; Leach, Lopa; Pritchard, David I

    2010-09-01

    Knowledge of the molecular mechanisms used by Necator americanus larvae to penetrate the human skin and the vasculature would aid the development of effective vaccines against this important pathogen. In this work, the impact of N. americanus exsheathing fluid (EF) and excretory/secretory products (ES) on the endothelial barrier was examined using human umbilical vein endothelial cells (HUVEC). Cellular responses were assessed by investigating molecular changes at cell-cell junctions and by determining levels of secreted IL-6, IL-8, and vascular endothelial growth factor (VEGF) in the culture medium. It would appear that a repertoire of larval proteases caused a dose-related increase in endothelial permeability as characterized by a decrease in monolayer resistance with increased permeation of tracer-albumin. These barrier changes were associated with disruption of junctional vascular endothelial cadherin (VE-cadherin) and F-actin and an increase in endothelial secretion of IL-6 and IL-8. Our data suggest that larval proteases play an important role in negotiating the endothelium.

  16. Exploring the Microbial Community of Shell Disease in Homarus americanus

    NASA Astrophysics Data System (ADS)

    Unzueta Martinez, A.; Feinman, S. G.; Bowen, J. L.; Tlusty, M. F.

    2016-02-01

    The American lobster, Homarus americanus is an important commercial fishery in New England, and generated nearly half a billion dollars in revenue in 2012. Outbreaks of shell disease among H. americanus populations have caused a great deal of concern regarding its cause and spread. Although shell disease is not usually lethal, afflicted lobsters have an unattractive appearance and are generally unmarketable. Shell disease is hypothesized to be caused by infectious microorganisms, but no etiological agent has been identified. This project characterizes the microbial communities associated with the formation of shell disease in lobsters and how these communities change during the progression of the disease. Microbial samples were collected on lobsters at the site of a new shell disease location, as well as at 0.5, 1, and 1.5 cm away from the site. Microbial DNA was extracted from each sample, the 16S rRNA gene amplified using PCR, and sequenced using high throughput sequencing. The results showed that microbial communities on diseased lobster shells were significantly different spatially, but not temporally. The diversity of microbes was lowest at the site of shell disease, and increased with distance from the site. This work elucidated the microbial community composition of shell disease, tracked this community throughout the progression of disease, and demonstrated a gradual rather than abrupt demarcation in microbial community between symptomatic and asymptomatic shell.

  17. HYDROCEPHALUS IN THREE JUVENILE NORTH AMERICAN BLACK BEARS (URSUS AMERICANUS).

    PubMed

    Ferguson, Sylvia H; Novak, Janelle; Hecht, Silke; Craig, Linden E

    2016-06-01

    Hydrocephalus has been reported in a variety of species, including the North American black bear ( Ursus americanus ). This report describes three cases of hydrocephalus in this species from wild bears aged 3-4 mo considered retrospectively from necropsy records of one institution. Clinical signs included cortical blindness and ataxia. Primary gross findings were doming of the skull, gyri compression and flattening, and lateral ventricle dilation. Two cases had severe bilateral ventricular dilation with loss of the septum pellucidum; atrophy of the surrounding corpus callosum; and bilateral periventricular tears involving the caudate nuclei, internal capsule, and adjacent cerebrum. Histologically, the cases with periventricular tearing had severe axonal loss and degeneration, malacia, hemorrhage, and variable periventricular astrocytosis. All cases were likely congenital, given the bears' age and lack of an apparent acquired obstruction.

  18. Tetranucleotide microsatellite loci from the black bear (Ursus americanus)

    USGS Publications Warehouse

    Sanderlin, J.S.; Faircloth, B.C.; Shamblin, B.; Conroy, M.J.

    2009-01-01

    We describe primers and polymerase chain reaction conditions to amplify 21 tetranucleotide microsatellite DNA loci in black bears (Ursus americanus). We tested primers using individuals from two populations, one each in Georgia and Florida. Among individuals from Georgia (n = 29), primer pairs yielded an average of 2.9 alleles (range, one to four) and an average observed heterozygosity (HO) of 0.50 (range, 0.00 to 0.79). Among individuals from Florida (n = 19), primer pairs yielded an average of 5.7 alleles (range, one to 14) and an HO of 0.55 (range, 0.00 to 1.00). A comparison of previously developed markers with individuals from Georgia suggests that bear populations in Georgia and Florida have reduced allelic diversity relative to other populations. ?? 2008 The Authors.

  19. Molecular immune response of the American lobster (Homarus americanus) to the White Spot Syndrome Virus.

    PubMed

    Clark, K Fraser; Greenwood, Spencer J; Acorn, Adam R; Byrne, Philip J

    2013-11-01

    The adult American lobster (Homarus americanus) is susceptible to few naturally occurring pathogens, and no viral pathogen is known to exist. Despite this, relatively little is known about the H. americanus immune system and nothing is known about its potential viral immune response. Hundreds of rural communities in Atlantic Canada rely on the lobster fishery for their economic sustainability and could be devastated by large-scale pathogen-mediated mortality events. The White Spot Syndrome Virus is the most economically devastating viral pathogen to global shrimp aquaculture production and has been proposed to be capable of infecting all decapod crustaceans including the European Lobster. An in vivo WSSV injection challenge was conducted in H. americanus and WSSV was found to be capable of infecting and replicating within lobsters held at 20°C. The in vivo WSSV challenge also generated the first viral disease model of H. americanus and allowed for the high-throughput examination of transcriptomic changes that occur during viral infection. Microarray analysis found 136 differentially expressed genes and the expression of a subset of these genes was verified using RT-qPCR. Anti-lipopolysaccharide isoforms and acute phase serum amyloid protein A expression did not change during WSSV infection, contrary to previous findings during bacterial and parasitic infection of H. americanus. This, along with the differential gene expression of thioredoxin and trypsin isoforms, provides compelling evidence that H. americanus is capable of mounting an immune response specific to infection by different pathogen classes.

  20. Spatial memory in captive American black bears (Ursus americanus).

    PubMed

    Zamisch, Valeria; Vonk, Jennifer

    2012-11-01

    The spatial memory and foraging strategies of four adult captive-born American black bears (Ursus americanus) were explored in four experiments using a simulated foraging task. In the first three experiments, each session consisted of two phases separated by a delay: During the exploration phase, subjects foraged among a set of baited and unbaited sites. During the delay, the same locations were rebaited and subjects were released again and allowed to search the sites (search phase). In Experiments 1a and 1b, different sites were baited each day and the interval between exploration and search was short (4 hr or 15 min). Subjects were not accurate at recovering the food items in either experiment. In Experiment 2, an "informed forager" paradigm was used in which one subject was given privileged knowledge about the location of the food during the exploration phase and was later released with an "uninformed" competitor during the search phase. The bears did not achieve above-chance recovery accuracy even in the presence of a competitor. In Experiment 3, the same two of four sites were continually baited and the bears were released simultaneously over a period of 20 days, with each baiting separated by 2 or 3 days. As a group, the bears' foraging accuracy with repeated baiting and longer intervals approached greater than chance accuracy. Results suggest some limitations on bears' use of spatial memory in captive environments, but reveal the potential for use of spatial memory over longer delays.

  1. Subcuticular urate accumulation in an American lobster (Homarus americanus).

    PubMed

    Battison, A L

    2013-05-01

    An unusually "lumpy" lobster, Homarus americanus, was presented to the Atlantic Veterinary College Lobster Science Centre for evaluation. The lobster was weak with numerous pale, raised, and flat areas (diameter, 3-15 mm) on the exoskeleton, some of which were ulcerated. On postmortem examination, the pale areas corresponded to accumulations of viscous to free-flowing white material, which was found in only the subcuticular connective tissues. No internal organs were affected. Direct light examination of nonstained impression smears of the material showed abundant crystals resembling uric acid, amorphous urates, and sodium urate, which were readily soluble in 1 M potassium hydroxide. Wright-Giemsa stained imprints showed numerous fine, rounded, nonstaining granules free in the background and within individual round cells. Fourier-transformed infrared spectroscopy confirmed the presence of urates or mixed urate salts. Hemolymph plasma urea (1.7 mmol/liter) and uric acid (287 μmol/liter) concentrations were slightly higher than those seen with 36-hour emersion. Histologic sections showed aggregates of vacuolated mononuclear cells in the loose subcuticular connective tissue occasionally infiltrating between underlying muscle fibers. Grossly visible urate deposits are occasionally documented in land crabs and rarely reported in the blue crab; none, however, are associated with deformation of the cuticle. Possible etiologies include increased uric acid intake or production or decreased excretion. Anecdotal reports of similarly affected lobsters have been received but are intermittent and undocumented.

  2. The complete genome sequence of 'Candidatus Liberibacter americanus', associated with Citrus huanglongbing.

    PubMed

    Wulff, Nelson A; Zhang, Shujian; Setubal, João C; Almeida, Nalvo F; Martins, Elaine C; Harakava, Ricardo; Kumar, Dibyendu; Rangel, Luiz Thiberio; Foissac, Xavier; Bové, Joseph M; Gabriel, Dean W

    2014-02-01

    Liberibacter spp. form a Rhizobiaceae clade of phloem-limited pathogens of limited host range. Two obligately parasitic species have been sequenced: 'Candidatus Liberibacter asiaticus', which causes citrus huanglongbing (HLB) worldwide, and 'Ca. L. solanacearum', which causes potato "zebra chip" disease. A third (proposed) species, Liberibacter crescens, was isolated from mountain papaya, grown in axenic culture, and sequenced. In an effort to identify common host determinants, the complete genomic DNA sequence of a second HLB species, 'Ca. L. americanus' strain 'São Paulo' was determined. The circular genome of 1,195,201 bp had an average 31.12% GC content and 983 predicted protein encoding genes, 800 (81.4%) of which had a predicted function. There were 658 genes common to all sequenced Liberibacter spp. and only 8 genes common to 'Ca. L. americanus' and 'Ca. L. asiaticus' but not found in 'Ca. L. solanacearum'. Surprisingly, most of the lipopolysaccharide biosynthetic genes were missing from the 'Ca. L. americanus' genome, as well as OmpA and a key regulator of flagellin, all indicating a 'Ca. L. americanus' strategy of avoiding production of major pathogen-associated molecular patterns present in 'Ca. L. asiaticus' and 'Ca. L. solanacearum'. As with 'Ca. L. asiaticus', one of two 'Ca. L. americanus' prophages replicated as an excision plasmid and carried potential lysogenic conversion genes that appeared fragmentary or degenerated in 'Ca. L. solanacearum'.

  3. The effect of fallow on Longidorus americanus, a nematode associated with stunting of loblolly pine seedlings in Georgia, USA

    Treesearch

    Stephen W. Fraedrich; Michelle M. Cram; Stanley J. Zarnoch

    2005-01-01

    Stunting of loblolly pine (Pinue taeda L.) seedlings, caused by Longidorus americanus, has been a problem at a Georgia (USA) nursery. Field and growth chamber studies were conducted to determine the survivability of the nematode in a fallow nursery soil. The population density of L. americanus decreased rapidly...

  4. Seroprevalence of Toxoplasma gondii from free-ranging black bears ( Ursus americanus ) from Florida.

    PubMed

    Chambers, D L; Ulrey, W A; Guthrie, J M; Kwok, O C H; Cox, J J; Maehr, D S; Dubey, J P

    2012-06-01

    Toxoplasma gondii is a significant worldwide parasitic protozoan. In the present study, prevalence of antibodies of T. gondii was examined from 29 free-ranging black bears ( Ursus americanus ) from south-central Florida where the host species was listed as state threatened during this project. Overall T. gondii prevalence was found to be 44.8%, specifically 46.2% in male and 43.8% in female U. americanus , using a modified agglutination test (1:25 titer). Seroprevalence differences between sexes were not significant (P > 0.05). Results of the present study add supportive data to the growing body of evidence suggesting that U. americanus has one of the highest T. gondii seroprevalences among all known intermediate hosts. In addition, our data emphasize the importance of understanding parasitic disease dynamics from a conservation perspective.

  5. Taxonomic recovery of the ant cricket Myrmecophilus albicinctus from M. americanus (Orthoptera, Myrmecophilidae)

    PubMed Central

    Komatsu, Takashi; Maruyama, Munetoshi

    2016-01-01

    Abstract Myrmecophilus americanus and Myrmecophilus albicinctus are typical myrmecophilous insects living inside ant nests. These species are ecologically important due to the obligate association with tramp ant species, including harmful invasive ant species. However, the taxonomy of these “white-banded ant crickets” is quite confused owing to a scarcity of useful external morphological characteristics. Recently, Myrmecophilus albicinctus was synonymized with Myrmecophilus americanus regardless of the apparent host use difference. To clarify taxonomical relationship between Myrmecophilus albicinctus and Myrmecophilus albicinctus, we reexamined morphological characteristics of both species mainly in the viewpoint of anatomy. Observation of genitalia parts, together with a few external body parts, revealed that Myrmecophilus albicinctus showed different tendency from them of Myrmecophilus americanus. Therefore, we recover Myrmecophilus albicinctus as a distinct species on the basis of the morphology. PMID:27408536

  6. Characterization and functional classification of American lobster (Homarus americanus) immune factor transcripts.

    PubMed

    Clark, K Fraser

    2014-11-01

    The American lobster (Homarus americanus) is the most important commercially exploited marine species in Canada. Very little is known about the H. americanus molecular humoral immune response or how to determine if a seemingly healthy lobster is infected with a pathogen. The goal of this work is to characterize several important H. americanus immune genes as well as highlight and classify hundreds of others into functional immune groups. The protein sequence of H. americanus acute phase serum amyloid protein A (SAA) was found to be similar to that of vertebrate SAA, and is likely a good clinical marker for immune activation in lobsters and some crustaceans. Additionally, only one gene, Trypsin 1b, was found to be differentially regulated during bacterial, microparasitic and viral challenges in lobster and is likely critical for the activation of the H. americanus immune response. Bioinformatic analysis was used to functionally annotate, 263 H. americanus immune genes and identify the few shared patterns of differential gene expression in lobsters in response to bacterial, parasitic and viral challenge. Many of the described immune genes are biomarker candidates which could be used as clinical indicators for lobster health and disease. Biomarkers can facilitate early detection of pathogens, or anthropomorphic stressors, so that mitigation strategies can be developed in order to prevent the devastating economic losses that have occurred in Southern New England, USA. This work is contributes to further our understanding of how the lobster immune system works and how it can be used to maintain the health and sustainability of the overall American lobster fishery.

  7. Neuropeptidergic Signaling in the American Lobster Homarus americanus: New Insights from High-Throughput Nucleotide Sequencing.

    PubMed

    Christie, Andrew E; Chi, Megan; Lameyer, Tess J; Pascual, Micah G; Shea, Devlin N; Stanhope, Meredith E; Schulz, David J; Dickinson, Patsy S

    2015-01-01

    Peptides are the largest and most diverse class of molecules used for neurochemical communication, playing key roles in the control of essentially all aspects of physiology and behavior. The American lobster, Homarus americanus, is a crustacean of commercial and biomedical importance; lobster growth and reproduction are under neuropeptidergic control, and portions of the lobster nervous system serve as models for understanding the general principles underlying rhythmic motor behavior (including peptidergic neuromodulation). While a number of neuropeptides have been identified from H. americanus, and the effects of some have been investigated at the cellular/systems levels, little is currently known about the molecular components of neuropeptidergic signaling in the lobster. Here, a H. americanus neural transcriptome was generated and mined for sequences encoding putative peptide precursors and receptors; 35 precursor- and 41 receptor-encoding transcripts were identified. We predicted 194 distinct neuropeptides from the deduced precursor proteins, including members of the adipokinetic hormone-corazonin-like peptide, allatostatin A, allatostatin C, bursicon, CCHamide, corazonin, crustacean cardioactive peptide, crustacean hyperglycemic hormone (CHH), CHH precursor-related peptide, diuretic hormone 31, diuretic hormone 44, eclosion hormone, FLRFamide, GSEFLamide, insulin-like peptide, intocin, leucokinin, myosuppressin, neuroparsin, neuropeptide F, orcokinin, pigment dispersing hormone, proctolin, pyrokinin, SIFamide, sulfakinin and tachykinin-related peptide families. While some of the predicted peptides are known H. americanus isoforms, most are novel identifications, more than doubling the extant lobster neuropeptidome. The deduced receptor proteins are the first descriptions of H. americanus neuropeptide receptors, and include ones for most of the peptide groups mentioned earlier, as well as those for ecdysis-triggering hormone, red pigment concentrating hormone

  8. Neuropeptidergic Signaling in the American Lobster Homarus americanus: New Insights from High-Throughput Nucleotide Sequencing

    PubMed Central

    Christie, Andrew E.; Chi, Megan; Lameyer, Tess J.; Pascual, Micah G.; Shea, Devlin N.; Stanhope, Meredith E.; Schulz, David J.; Dickinson, Patsy S.

    2015-01-01

    Peptides are the largest and most diverse class of molecules used for neurochemical communication, playing key roles in the control of essentially all aspects of physiology and behavior. The American lobster, Homarus americanus, is a crustacean of commercial and biomedical importance; lobster growth and reproduction are under neuropeptidergic control, and portions of the lobster nervous system serve as models for understanding the general principles underlying rhythmic motor behavior (including peptidergic neuromodulation). While a number of neuropeptides have been identified from H. americanus, and the effects of some have been investigated at the cellular/systems levels, little is currently known about the molecular components of neuropeptidergic signaling in the lobster. Here, a H. americanus neural transcriptome was generated and mined for sequences encoding putative peptide precursors and receptors; 35 precursor- and 41 receptor-encoding transcripts were identified. We predicted 194 distinct neuropeptides from the deduced precursor proteins, including members of the adipokinetic hormone-corazonin-like peptide, allatostatin A, allatostatin C, bursicon, CCHamide, corazonin, crustacean cardioactive peptide, crustacean hyperglycemic hormone (CHH), CHH precursor-related peptide, diuretic hormone 31, diuretic hormone 44, eclosion hormone, FLRFamide, GSEFLamide, insulin-like peptide, intocin, leucokinin, myosuppressin, neuroparsin, neuropeptide F, orcokinin, pigment dispersing hormone, proctolin, pyrokinin, SIFamide, sulfakinin and tachykinin-related peptide families. While some of the predicted peptides are known H. americanus isoforms, most are novel identifications, more than doubling the extant lobster neuropeptidome. The deduced receptor proteins are the first descriptions of H. americanus neuropeptide receptors, and include ones for most of the peptide groups mentioned earlier, as well as those for ecdysis-triggering hormone, red pigment concentrating hormone

  9. Morphological Dependence of Element Stoichiometry in the H. americanus Exoskeleton

    NASA Astrophysics Data System (ADS)

    Mergelsberg, S. T.; Ulrich, R. N.; Dove, P. M.

    2016-02-01

    The crustacean exoskeleton is a complex biocomposite of inorganic mineral and organic macromolecules that expresses highly divergent morphologies across different taxa. While the structures and compositions of the organic framework show complex links to environmental and developmental pressures, little is known about the mineral chemistry. Previous studies of the cuticle have assumed that magnesium, phosphorous, and other trace metals are largely contained in the inorganic mineral fraction. Due to analytical limitations of structural analyses and in situ spectroscopic methods, the stoichiometry of the organic and inorganic portions could not be resolved. For example, previous Raman and XRD studies conclude the higher concentrations of trace elements, such as P and Mg measured in reinforced structures, e.g. the claw and abdomen, are primarily determined by the mineral fraction. Using the American Lobster (Homarus americanus) as a model organism to establish relationships between body part function and cuticle composition, this study quantified the distributions of Mg and P in the mineral and organic fractions. The experiments were designed to dissolve the exoskeleton of 10 body parts using three types of solutions that were specific to extracting 1) the mineral phase, 2) protein, and 3) polysaccharide. Analysis of the solutions by ICP-OES shows the mineral phase contains magnesium and phosphorous at concentrations sufficient to support the formation of calcium-magnesium and phosphate minerals. The protein fraction of the body parts contains significantly more Mg and P than previously hypothesized, while the levels of P contained in the organic portion are fairly constant. The findings demonstrate the lobster cuticle contains a significant amount of non-mineralized P and Mg that is readily water-soluble in the protein component. However, for those body parts used for defense and food acquisition, such as the claw, the mineral component determines the overall

  10. Blindness in a wild American black bear cub (Ursus americanus).

    PubMed

    Dombrowski, Elizabeth; McGregor, Glenna F; Bauer, Bianca S; Parker, Dennilyn; Grahn, Bruce H

    2016-07-01

    An approximately six-month-old wild American black bear (Ursus americanus) was found wandering in Saskatchewan and was presented to the Veterinary Medical Centre of the Western College of Veterinary Medicine for apparent blindness. Clinical examination confirmed an inability to navigate a photopic maze, bilateral tapetal hyper-reflectivity, fundi devoid of retinal vessels, and small pale optic nerve papillae. Single-flash electroretinography revealed A and B-wave amplitudes of approximately 40 and 140 microvolts, respectively, in both eyes. Histologic abnormalities included bilateral optic papillary mineralization and bilateral segmental optic nerve degeneration, with occasional intralesional lymphocytes confirmed with immunohistochemistry for CD3+. There was also bilateral multifocal retinal dysplasia, gliosis, lymphocytic retinitis, a complete lack of retinal blood vessels, an intravitreal vascular membrane, and a mild lymphocytic-plasmacytic uveitis with small pre-iridal cellular membranes. The presence of a positive ERG in a blind bear with numerous retinal ganglion cells and degenerative changes in the optic nerve are most consistent with vision loss due to optic nerve injury, which given the young age of the bear likely occurred during ocular development. The presence of ocular inflammation suggests this injury resulted from an inflammatory/infectious process. The etiology could not be determined. Hepatic concentrations of vitamin A were within the normal reference range for domestic species. Pan-herpesvirus PCR and immunohistochemistry for canine distemper virus and Toxoplasma gondii were negative, although this does not rule out these or other infectious etiologies. This represents the first case report of neonatal or congenital ocular abnormalities in an ursid species.

  11. Seroprevalence of Toxoplasma gondii in American Black Bears ( Ursus americanus ) of the Central Appalachians, USA.

    PubMed

    Cox, John J; Murphy, Sean M; Augustine, Ben C; Guthrie, Joseph M; Hast, John T; Maehr, Sutton C; McDermott, Joseph

    2017-07-01

    We assessed Toxoplasma gondii seroprevalence in 53 free-ranging American black bears ( Ursus americanus ) in the Central Appalachian Mountains, US. Seroprevalence was 62% with no difference between males and females or between juvenile and adult bears. Wildlife agencies should consider warnings in hunter education programs to reduce the chances for human infection from this source.

  12. Prevalence of Anaplasma phagocytophilum in North Carolina Eastern Black Bears ( Ursus americanus ).

    PubMed

    Westmoreland, Lori S H; Stoskopf, Michael K; Maggi, Ricardo G

    2016-10-01

    We detected Anaplasma phagocytophilum by DNA amplification in whole blood from free-ranging, hunter-killed American black bears ( Ursus americanus ) from the east coast of North Carolina, US. Molecular prevalence for Anaplasma phagocytophilum was 3% from 68 black bears. No DNA of other Anaplasma or Ehrlichia spp. was identified.

  13. Draft Genome Sequence of "Candidatus Liberibacter americanus" Bacterium Associated with Citrus Huanglongbing in Brazil.

    PubMed

    Lin, Hong; Coletta-Filho, Helvecio D; Han, Cliff S; Lou, Binghai; Civerolo, Edwin L; Machado, Marcos A; Gupta, Goutam

    2013-05-23

    We report here the draft genome sequence of "Candidatus Liberibacter americanus" strain PW_SP. The 1,176,071-bp genome, with 31.6% G+C content, comprises 948 open reading frames, 38 tRNAs, and three complete rRNAs.

  14. Potential Vertical Transmission of Winter Ticks (Dermacentor albipictus) from Moose (Alces americanus) Dams to Neonates.

    PubMed

    Severud, William J; DelGiudice, Glenn D

    2016-01-01

    North American moose (Alces americanus) frequently become infested with winter ticks (Dermacentor albipictus). During capture of neonatal moose in northeastern Minnesota, US, in May-June 2013 and 2014, we recovered adult ticks from neonates, presumably vertically transferred from dams, heretofore, not documented. Infestations on neonates may have population-level implications.

  15. Stable Carbon and Oxygen Isotope Ratios of Otoliths Differentiate Winter Flounder (Pseudopleuonectes americanus) Habitats

    EPA Science Inventory

    Stable carbon (13C) and oxygen (18O) isotope ratios were measured in otoliths of juvenile winter flounder (Pseudopleuronectes americanus) collected from 18 nursery areas along the coast of Rhode Island, USA. Samples were obtained during June and July of 2002 from locations tha...

  16. Stable Carbon and Oxygen Isotope Ratios of Otoliths Differentiate Winter Flounder (Pseudopleuonectes americanus) Habitats

    EPA Science Inventory

    Stable carbon (13C) and oxygen (18O) isotope ratios were measured in otoliths of juvenile winter flounder (Pseudopleuronectes americanus) collected from 18 nursery areas along the coast of Rhode Island, USA. Samples were obtained during June and July of 2002 from locations tha...

  17. Movements, activity patterns, and habitat use of snowshoe hares (Lepus americanus) in interior Alaska

    Treesearch

    D. Feierabend; K. Kielland

    2014-01-01

    Snowshoe hares (Lepus americanus) are generally sedentary, but are likely to move among habitats frequently to gain access to spatially segregated food and cover. We investigated movement patterns of hares from 2 characteristic boreal habitats using very-high-frequency radio collars (n ¼ 300) monitored weekly and global positioning system (GPS) collars (n ¼ 18)...

  18. SARCOCYSTIS URSUSI, N. SP (APICOMPLEXA; SARCOCYSTIDAE) FROM THE BLACK BEAR (URSUS AMERICANUS)

    USDA-ARS?s Scientific Manuscript database

    Infection with Sarcocystis species is common in hervibores but is rare in bears. Histological sections of 374 black bears (Ursus americanus) from Pennsylvania were examined for sarcocysts. A total of 3 sarcocysts were found in 3 bears, 1 sarcocyst per section. Sarcocysts from 2 bears were considered...

  19. Assessment of Dredge-induced Sedimentation Effects on Winter Flounder (pseudopleuronectes americanus) Hatching Success: Results of Laboratory Investigations

    EPA Science Inventory

    Historically of significant commercial and recreational value, winter flounder (Pseudopleuronectes americanus) stocks have declined steadily over the last 20 years and are currently at an all-time low. Although overfishing and climate change have been implicated, habitat alterat...

  20. Assessment of Dredging-Induced Sedimentation Effects on Winter Flounder (Pseudopleuronectes americanus) Hatching Success: Results of Laboratory Investigations

    EPA Science Inventory

    Historically of significant commercial and recreational value, winter flounder (Pseudopleuronectes americanus) stocks have declined steadily over the last 20 years and are currently at an all-time low. Although overfishing and climate change have been implicated, habitat alterat...

  1. Assessment of Dredge-induced Sedimentation Effects on Winter Flounder (pseudopleuronectes americanus) Hatching Success: Results of Laboratory Investigations

    EPA Science Inventory

    Historically of significant commercial and recreational value, winter flounder (Pseudopleuronectes americanus) stocks have declined steadily over the last 20 years and are currently at an all-time low. Although overfishing and climate change have been implicated, habitat alterat...

  2. Assessment of Dredging-Induced Sedimentation Effects on Winter Flounder (Pseudopleuronectes americanus) Hatching Success: Results of Laboratory Investigations

    EPA Science Inventory

    Historically of significant commercial and recreational value, winter flounder (Pseudopleuronectes americanus) stocks have declined steadily over the last 20 years and are currently at an all-time low. Although overfishing and climate change have been implicated, habitat alterat...

  3. Microlichus americanus acariasis in saffron finches (Sicalis flaveola) with dermatitis and feather loss.

    PubMed

    Rettenmund, Christy L; Ossiboff, Robert J; McAloose, Denise; Knee, Wayne; Wade, Susan E; Paré, Jean A

    2015-05-01

    Over a 5-year period, 13 saffron finches (Sicalis flaveola) housed in mixed aviaries at the Bronx Zoo (Bronx, New York) were examined with feather loss and dermatitis, primarily affecting the nape, neck, and dorsum. Feather loss, hyperkeratosis, epidermal hyperplasia, and mixed granulocytic and mononuclear inflammation were identified in biopsies from live birds and tissue sections from postmortem specimens. In 10 of 13 cases, sections of arthropod parasites were seen histologically within feather follicles and along the surface of affected skin. Based on morphological characteristics, mites recovered from samples of formalin-fixed skin in 4 birds were identified as Microlichus americanus, an epidermoptid mite infrequently reported from wild birds and hippoboscid flies. Gross and histological lesions strongly implicate M. americanus as the cause of dermatitis affecting practically all saffron finches in the collection.

  4. External morphology of the cycliophoran dwarf male: a comparative study of Symbion pandora and S. americanus

    NASA Astrophysics Data System (ADS)

    Neves, Ricardo Cardoso; da Cunha, Marina Ribeiro; Funch, Peter; Wanninger, Andreas; Kristensen, Reinhardt Møbjerg

    2010-09-01

    Cycliophora is a recently described phylum to which only two species have been assigned so far, Symbion pandora and S. americanus. The cycliophoran life cycle is complex and alternates between asexual and sexual stages. Although not recognized as an entirely independent free-swimming stage when the phylum was first described, the dwarf male has a remarkably complex bodyplan albeit its very small size (approx. 30-40 μm in length). Aiming to increase the knowledge on the gross morphology of the cycliophoran dwarf male, specimens from S. pandora and S. americanus were analyzed by scanning electron microscopy. In both species, anterior and ventral ciliated fields, as well as paired lateral sensorial organs, were identified, thus confirming previous observations. However, new details are described herein such as the penial pouch that encloses the penis. We compare our findings on both Symbion species with the data currently available on other metazoan dwarf males.

  5. A microchannel confocal examination of arsenic speciation and distribution in Bufo americanus

    NASA Astrophysics Data System (ADS)

    Nearing, Michelle M.; Koch, Iris; Gordon, Robert A.; Reimer, Kenneth J.

    2016-05-01

    We have used confocal methods to examine the distribution and speciation of arsenic within amphibian tissue (Bufo americanus) from a contaminated mine site. The use of new microchannel technology permits a confocal, and energy-independent, examination of a given voxel within the amphibian tissue without the need for sectioning. We observe differences in arsenic concentration and speciation depending on tissue type, with the Eberth- Katschenko layer in particular containing Mn, Fe, Cu and Zn in addition to Ca and pentavalent arsenic.

  6. Cultivation of 'Candidatus Liberibacter asiaticus', 'Ca. L. africanus', and 'Ca. L. americanus' associated with huanglongbing.

    PubMed

    Sechler, A; Schuenzel, E L; Cooke, P; Donnua, S; Thaveechai, N; Postnikova, E; Stone, A L; Schneider, W L; Damsteegt, V D; Schaad, N W

    2009-05-01

    A new medium designated Liber A has been designed and used to successfully cultivate all three 'Candidatus Liberibacter spp.,' the suspect causative agents of huanglongbing (HLB) in citrus. The medium containing citrus vein extract and a growth factor sustained growth of 'Ca. Liberibacter spp.' for four or five single-colony transfers before viability declined. Colonies, positive for 'Ca. L. asiaticus' by a 16s-based rDNA real-time polymerase chain reaction (RT-PCR) assay and sequencing, were irregular-shaped, convex, and 0.1 to 0.3 mm after 3 to 4 days. Suspect 'Ca. L. asiaticus' and 'Ca. L. americanus' cells were observed in infected tissue and on agar culture by scanning electron microscopy. The cells were ovoid to rod shaped, 0.3 to 0.4 by 0.5 to 2.0 microm, often with fimbriae-like appendages. Two strains of 'Ca. L. asiaticus' and one of 'Ca. L. americanus' grown on Liber A medium were pathogenic on citrus and could be isolated from noninoculated tissues of inoculated trees and seedlings 9 and 2 months later, respectively. The identity was confirmed by RT-PCR and 16s rDNA sequencing. This is the first report of the cultivation and pathogenicity of 'Ca. L. asiaticus' and 'Ca. L. americanus' associated with symptoms of HLB.

  7. Sequence data mining in search of hookworm (Necator americanus) microRNAs.

    PubMed

    Kulkarni, Abhijeet P; Mittal, Smriti P K

    2016-09-30

    The new world hookworm, Necator americanus is a soil-transmitted nematode responsible for Necatoriasis (a type of helminthiasis) in hosts such as humans, dogs, and cats. N. americanus genome and transcriptome has been sequenced and a draft assembly analysis has been published highlighting protein coding genes and possible drug target proteins. Hookworm microRNA identification, annotations and their public release is yet to be attempted. The same is evident from lack of hookworm miRNA information in related popular public nucleotide sequence repositories such as miRBase, GenBank, WormBase etc. Therefore, in the present study we addressed these issues using EST and assembled transcript sequence information of hookworm. Using computational approaches, we identified three miRNAs precursor sequences and their mature forms. We also identified their potential targets from hookworm ESTs and transcripts, and from human transcriptome. Overall, the results indicate presence of nematode specific miRNA homologs in N. americanus and shades light on their putative targets in worm itself and the human host.

  8. Improved insights into the transcriptomes of the human hookworm Necator americanus--fundamental and biotechnological implications.

    PubMed

    Rabelo, Elida M; Hall, Ross S; Loukas, Alex; Cooper, Leanne; Hu, Min; Ranganathan, Shoba; Gasser, Robin B

    2009-01-01

    Hookworms of humans are blood-feeding parasitic nematodes of major socio-economic significance in a wide range of countries. They cause a neglected tropical disease (NTD) called "hookworm disease" (=necatoriasis and/or ancylostomiasis). Necator americanus is the most widely distributed hookworm of humans and is a leading cause of iron deficiency anaemia, which can cause physical and mental retardation and deaths in children as well as adverse maternal-foetal outcomes. Currently, there is a significant focus on the development of new approaches for the prevention and control of hookworms in humans. Technological advances are underpinning the discovery of drug and vaccine targets through insights into the molecular biology and genomics of these parasites and their relationship with the human host. In spite of the widespread socio-economic impacts of human necatoriasis, molecular datasets for N. americanus are scant, limiting progress in molecular research. The present article explores all currently available EST datasets for adult and larval stages of N. americanus using a semi-automated bioinformatic pipeline. In the current repertoire of molecules now available, some have been or are being considered as candidate vaccines against N. americanus. Among others, the most abundant sets of molecules relate to the pathogenesis-related protein (PRP) superfamily, comprising various members, such as the Ancylostoma-secreted or activation-associated proteins (ASPs) and the kunitz-type proteins, both of which are inferred to play key roles in the interplay between N. americanus and the human host. Understanding the molecular biology of these and other novel molecules discovered could have important implications for finding new ways of disrupting the pathways that they are involved in, and should facilitate the identification of new drug and vaccine targets. Also, the bioinformatic prediction of the essentiality of genes and gene products as well as molecular network

  9. Historical wetlands in Oregon's Willamette Valley: Implications for restoration of winter waterbird habitat

    USGS Publications Warehouse

    Taft, Oriane W.; Haig, Susan M.

    2003-01-01

    Before agricultural expansion in the 19th century, river valleys of North America supported expanses of wetland habitat. In restoring these landscapes, it is important to understand their historical condition and biological function. Synthesizing historical primary accounts (from explorers, travelers, settlers, and farmers) with contemporary knowledge of these wetland systems, we developed a profile of the wetlands and their use by nonbreeding waterbirds (e.g., waterfowl, wading birds, and shorebirds) within the Willamette Valley, Oregon, ca. 1840. We found evidence for three types of wetlands used by non-breeding waterbirds in fall, winter, and spring: emergent wetlands, riverine wetlands, and wetland prairie. The most extensive wetland type was wetland prairie, which functioned as fall/winter habitat for waterbirds, but only while native Kalapuyans managed the region with fire. Since the mid-1800s, four species, in particular, have decreased their use of the Willamette Valley: trumpeter swan (Cygnus buccinator), snow goose (Chen caerulescens), sandhill crane (Grus canadensis), and long-billed curlew (Numenius americanus). Information suggests that ca. 1840, waterbirds and their habitats were more abundant in the Willamette Valley than today. Restoration of the Willamette Valley landscape is warranted, and today's agricultural wetlandsa??former wetland prairiea??hold highest restoration potential.

  10. First record of the ant cricket Myrmecophilus (Myrmecophilina) americanus (Orthoptera: Myrmecophilidae) in Mexico.

    PubMed

    Ortega-Morales, Aldo I; Rodríguez, Quetzaly K Siller; Garza-Hernández, Javier A; Adeniran, Adebiyi A; Hernández-Triana, Luis M; Rodríguez-Pérez, Mario A

    2017-04-27

    In September 2004, the New World ant cricket, Myrmecophilus americanus Saussure, 1877, was collected in association with longhorn crazy ants, Paratrechina longicornis (Latreille. 1802), in the state of Coahuila, Mexico. We are reporting the DNA barcode using the mitochrondrial cytochrome oxidase subunit I for this first record of M. americanus in Mexico.

  11. Isothermal Diagnostic Assays for Monitoring Single Nucleotide Polymorphisms in Necator americanus Associated with Benzimidazole Drug Resistance

    PubMed Central

    Rashwan, Nour; Bourguinat, Catherine; Keller, Kathy; Gunawardena, Nipul Kithsiri; de Silva, Nilanthi; Prichard, Roger

    2016-01-01

    Background Soil-transmitted helminths (STHs) are the most prevalent intestinal helminths of humans, and a major cause of morbidity in tropical and subtropical countries. The benzimidazole (BZ) drugs albendazole (ABZ) and mebendazole (MBZ) are used for treatment of human STH infections and this use is increasing dramatically with massive drug donations. Frequent and prolonged use of these drugs could lead to the emergence of anthelmintic resistance as has occurred in nematodes of livestock. Previous molecular assays for putative resistance mutations have been based mainly on PCR amplification and sequencing. However, these techniques are complicated and time consuming and not suitable for resource-constrained situations. A simple, rapid and sensitive genotyping method is required to monitor for possible developing resistance to BZ drugs. Methods To address this problem, single nucleotide polymorphism (SNP) detection assays were developed based on the Smart amplification method (SmartAmp2) to target codons 167, 198, and 200 in the β-tubulin isotype 1 gene for the hookworm Necator americanus. Findings Diagnostic assays were developed and applied to analyze hookworm samples by both SmartAmp2 and conventional sequencing methods and the results showed high concordance. Additionally, fecal samples spiked with N. americanus larvae were assessed and the results showed that the Aac polymerase used has high tolerance to inhibitors in fecal samples. Conclusion The N. americanus SmartAmp2 SNP detection assay is a new genotyping tool that is rapid, sensitive, highly specific and efficient with the potential to be used as a field tool for monitoring SNPs associated with BZ resistance. However, further validation on large numbers of field samples is required. PMID:27930648

  12. Studies on endoparasites of the black bear (Ursus americanus) in the southeastern United States.

    PubMed

    Crum, J M; Nettles, V F; Davidson, W R

    1978-04-01

    Examination of 53 black bears (Ursus americanus) from six states in the southeastern United States revealed at least 17 species of endoparasites, including Sarcocystis sp., Spirometra mansonoides (spargana), Macracanthorhynchus ingens, Ancylostoma caninum, Arthrocephalus lotoris, Baylisascaris transfuga, Capillaria aerophila, Capillaria putorii, Crenosoma sp., Cyathospirura sp., Dirofilaria immitis, Gnathostoma sp., Gongylonema pulchrum, microfilariae, Molineus barbatus, Physaloptera sp. and Strongyloides sp. Twelve of these represent new host records for black bear, and two are considered to be new species. Data are presented on prevalence, intensity and geographic distribution of each species. Pathologic effects were associated with infections of spargana of S. mansonoides and adults of C. aerophilia.

  13. SURGICAL CORRECTION OF BILATERAL PATELLAR LUXATION IN AN AMERICAN BLACK BEAR CUB (URSUS AMERICANUS).

    PubMed

    Bennett, Katarina R; Desmarchelier, Marion R; Bailey, Trina R

    2015-06-01

    A wild orphaned male American black bear cub ( Ursus americanus ) presented with hind limb gait abnormalities and was found to have bilateral grade 3 laterally luxating patellas. There were no other significant abnormalities detected on neurologic, radiographic, or hematologic examinations. The trochlear grooves were deepened with a chondroplasty, and the redundant soft tissues imbricated. There was a marked improvement in the bear's gait postoperatively, with an apparent full return to function. To the authors' knowledge, patellar luxation has not been reported in the Ursidae family, and the success in this case suggests that this technique may be used in large wild or captive carnivore cubs.

  14. Mediastinal teratoma in a free-ranging American black bear (Ursus americanus).

    PubMed

    Munk, Brandon A; Turner, J Chris; Keel, M Kevin

    2013-12-01

    A 2.75-yr-old female American black bear (Ursus americanus) was found emaciated and unable to rise. It was euthanized due to the perceived poor prognosis. An approximately 18 x 8 x 10-cm, multiloculated, well-demarcated mass that extended from the bifurcation of the trachea, laterally displacing the lung lobes and caudally displacing the heart. The mass contained fibrous connective tissue, cartilage, bone, nervous tissue, smooth muscle, and a variety of epithelial structures. A mediastinal teratoma was diagnosed based on the microscopic features of the neoplasm.

  15. Consumption of seeds of southwestern white pine (Pinus strobiformis) by Black Bear (Ursus americanus)

    USGS Publications Warehouse

    Mattson, David J.; Arundel, Terry A.

    2013-01-01

    We report a discovery of black bears (Ursus americanus) consuming seeds of southwestern white pine (Pinus strobiformis) on north slopes of the San Francisco Peaks near Flagstaff, Arizona, in high-elevation, mixed-species conifer forest. In one instance, a bear had obtained seeds from cones excavated from a larder horde made by a red squirrel (Tamiasciurus hudsonicus). Consumption of seeds of southwestern white pine by bears had not been previously documented. This discovery adds to the number of species of pine used by bears for food as well as the geographic range within which the behavior occurs.

  16. Fatal disseminated blastomycosis in a free-ranging American black bear (Ursus americanus).

    PubMed

    Dykstra, Jaclyn A; Rogers, Lynn L; Mansfield, Susan A; Wünschmann, Arno

    2012-11-01

    An aged, free-ranging, female, radio-collared American black bear (Ursus americanus) died after an approximately 5 month long period of weight loss. Gross necropsy findings included severe diffuse pyogranulomatous bronchopneumonia, marked granulomatous lymphadenitis of tracheobronchial lymph nodes and multiple intra-abdominal lymph nodes, chronic focal jejunal ulceration, and widespread alopecia. Histopathologic examination revealed abundant fungal organisms morphologically compatible with Blastomyces sp. within pyogranulomatous inflammatory lesions in the lungs, multiple lymph nodes, liver, kidneys, jejunum, and right adrenal gland. In addition, the haircoat had a mild infestation of chewing lice (Trichodectes pinguis euarctidos), and large numbers of rhabditid nematodes consistent with Pelodera sp. were histologically observed within hair follicles.

  17. Sinorhizobium americanus sp. nov., a new Sinorhizobium species nodulating native Acacia spp. in Mexico.

    PubMed

    Toledo, Ivonne; Lloret, Lourdes; Martínez-Romero, Esperanza

    2003-03-01

    The sinorhizobia isolated from root nodules of Acacia species native of Mexico constitute a diverse group of bacteria on the basis of their metabolic enzyme electromorphs but share restriction patterns of the PCR products of 16S rRNA genes and a common 500 kb symbiotic plasmid. They are distinguished from other Sinorhizobium species by their levels of DNA-DNA hybridization and the sequence of 16S rRNA and nifH genes. nolR gene hybridization patterns were found useful to identify sinorhizobia and characterize species. A new species, Sinorhizobium americanus, is described and the type strain is CFNEI 156 from Acacia acatlensis.

  18. The relationship between Pseudodiplorchis americanus (Monogenea) density and host resources under controlled environmental conditions.

    PubMed

    Tocque, K; Tinsley, R C

    1994-02-01

    A previous study has shown that, under natural conditions, energy reserves of the desert toad, Scaphiopus couchii, are negatively related to the density of infection by Pseudodiplorchis americanus. However, this was based predominantly on collections of active animals from breeding congregations and inevitably selected toads which were in good condition. The parasite, a blood-feeding monogenean, occurs in burdens of up to 30 worms/host (mean intensity 6 worms/host) and represents a significant drain on reserves because the host does not feed during a 10-month hibernation. Field studies cannot resolve the possibility that larger worm densities are not observed in nature due to parasite-induced host mortality. The present study was conducted during investigations of P. americanus development and survival under controlled laboratory conditions, utilizing experimentally infected hosts which created worm densities larger than those observed in natural populations. At all temperature regimes, infected animals had smaller fat bodies than those uninfected but differences were generally not statistically significant due to large individual variations, presumably resulting from variations in past feeding efficiency. At cool temperatures (15-20 degrees C) there was no density-dependent effect on host fat body weight, and at a diurnal temperature cycle of 20-34 degrees C (simulating that experienced by host and parasite during the summer months), the effects of high temperatures were greater than the effects of infection, due to increased toad metabolic rates. The most significant effects of P. americanus were observed in hosts that began hibernation in relatively poor condition and experienced moderate temperatures (25 degrees C) during hibernation. The toads generally maintained packed blood cell levels (PCV) levels even when fat body weights were low, but infected animals had a lower PCV irrespective of fab body levels. In animals unfed after field collection, PCV was

  19. Seasonal and daily plasma corticosterone rhythms in American toads, Bufo americanus

    SciTech Connect

    Pancak, M.K.; Taylor, D.H.

    1983-06-01

    Concentrations of corticosterone were measured in the plasma of American toads, Bufo americanus, on a seasonal basis using a radioimmunoassay technique. Two populations of toads, maintained under different light conditions, were monitored to observe the effects of photoperiod on the seasonal rhythm of plasma corticosterone. Under a natural photoperiod toads demonstrated a rhythm consisting of a spring peak and a fall peak in corticosterone concentration. Toads maintained under a 12L:12D photoperiod all year round demonstrated a similar rhythm with peaks in the spring and fall. This suggests that an endogenous (circannual) rhythm of corticosterone may be playing an important role in the seasonal change of overt behavior and physiology of Bufo americanus. A daily rhythm of corticosterone was also detected in toads when blood samples were taken every 4 hr. When compared to a previously published circadian rhythm study of locomotor activity, the surge in corticosterone concentration for the day occurred at 1730 just prior to the peak in locomotor activity.

  20. Chaoborus americanus predation on various zooplankters; Functional response and behavioral observations.

    PubMed

    Vinyard, Gary L; Menger, R A

    1980-04-01

    Predation rates for Chaoborus americanus on different types of noncyclomorphic zooplankton prey were determined in the laboratory as a function of both prey species and density. The sequence of events leading to consumption of prey was also observed, and probabilities determined for the various components.Predation rates generally reached an upper limit as the density of prey increased to high levels. Larger prey were always less vulnerable to Chaoborus predation. Among the species of zooplankton prey examined Holopedium gibberum suffered the lowest rates of predation, while those of the other plankters (Daphnia pulex, D. rosea, Moina hutchinsoni, Diaptomus birgei, D. leptopus, Cyclops vernalis) were approximately equivalent for any given size category.Observation of the predatory sequence indicates that for all the plankters except H. gibberum there were relatively high rates of evasion of attack by C. americanus and low rates of escape after capture. For H. gibberum the situation was reversed, and escape after capture was particularly important in determining the predation rate.The gelatinous envelope of Holopedium gibberum seems to operate as an effective anti-predator device which reduces the likelyhood of retention by Chaoborus after contact has been made.

  1. Comparative tissue expression of American lobster (Homarus americanus) immune genes during bacterial and scuticociliate challenge.

    PubMed

    Clark, K Fraser; Acorn, Adam R; Wang, Haili; Greenwood, Spencer J

    2015-12-01

    The American lobster (Homarus americanus) fishery is the most economically significant fishery in Canada; although comparatively little is known about the lobsters' response to pathogenic challenge. This is the first study to investigate the expression of immune genes in tissues outside of the lobster hepatopancreas in response to challenges by the Gram-positive bacteria, Aerococcus viridans var. homari or the scuticociliate parasite, Anophryoides haemophila. The hepatopancreas has been regarded as the major humoral immune organ in crustaceans, but the contribution of other organs and tissues to the molecular immune response has largely been overlooked. This study used RT-qPCR to monitor the gene expression of several immune genes including three anti-lipopolysaccharide isoforms (ALF) Homame ALF-B1, Homame ALF-C1 and ALFHa-1, acute phase serum amyloid protein A (SAA), as well as thioredoxin and hexokinase, in antennal gland and gill tissues. Our findings indicate that the gene expression of the SAA and all ALF isoforms in the antennal gland and gill tissues increased in response to pathogenic challenge. However, there was differential expression of individual ALF isoforms that were dependent on both the tissue, and the pathogen used in the challenge. The gene expression changes of several immune genes were found to be higher in the antennal gland than have been previously reported for the hepatopancreas. This study demonstrates that increased immune gene expression from the gill and antennal gland over the course of pathogen induced disease contributes to the immune response of H. americanus.

  2. Sarcocystis sp. in mountain goats (Oreamnos americanus) in Washington: prevalence and search for the definitive host.

    PubMed

    Foreyt, W J

    1989-10-01

    During October and November 1986, Sarcocystis sp. was detected in 24 of 56 (43%) tongues from hunter-killed mountain goats (Oreamnos americanus) in Washington (USA). Sarcocysts had an unusual sessile polyp-shaped branched wall. Mean size of 154 sarcocysts was 71.3 x 37.8 microns (range, 20 to 248 x 10 to 120 microns), and the mean intensity was 2.3 (range, 1 to 28). In an attempt to identify the definitive host, infected tongues were fed to four coyotes (Canis latrans), eight domestic dogs, four domestic cats, three bears (Ursus americanus), two raccoons (Procyon lotor), two martens (Martes americana), two fishers (Martes pennanti), three skunks (Mephitis mephitis), five mink (Mustela vison), five ferrets (Mustela putorius), one pigtail macaque (Macaca nemestrina), two red-tailed hawks (Buteo jamaicensis) and one great horned owl (Bubo virginianus). Oocysts or sporocysts were not detected in the feces of any host for less than or equal to 20 days after ingestion of the infected meat. The definitive host for Sarcocystis sp. in mountain goats was not identified.

  3. Developmental Effects of Ocean Acidification Conditions and Elevated Temperature on Homarus Americanus Larvae

    NASA Astrophysics Data System (ADS)

    Mcveigh, H.; Waller, J. D.

    2016-02-01

    The Gulf of Maine is experiencing a rapid warming in sea surface temperature and a marked decrease in pH. This study aimed to quantify the impact of elevated temperature and acidification on the larval development of the iconic American lobster (Homarus americanus). Experimental conditions were reflective of current and IPCC predicted levels of temperature and pCO2 to be reached by the end of the century. Larvae were measured for growth (carapace length), development time, and survivorship over the larval duration. Treatments of elevated temperatures experienced decreased development time across the larval stages of H. americanus. Consequently mortality increased at a significantly higher rate under elevated temperature. An increase in larval mortality may decrease recruitment to the commercial fishery, thus impacting the most valuable single species in the state of Maine. Furthermore, experimental pCO2 treatments yielded a significantly decreased development time between larval stages II and III, yet did not have a significant impact on carapace length or mortality. This study indicates that warmer temperatures may have a greater influence than decreased pH on larval development and survival. Determining how this species may respond to changing climactic conditions will better inform the sustainability efforts of such a critical marine fishery.

  4. A novel isothermal microcalorimetry tool to assess drug effects on Ancylostoma ceylanicum and Necator americanus.

    PubMed

    Flores, Dayana; Panic, Gordana; Braissant, Olivier; Keiser, Jennifer

    2016-01-01

    Soil-transmitted helminths, which affect the poorest communities, worldwide cause a range of symptoms and morbidity, yet few treatment options are available and drug resistance is a concern. To improve and accelerate anthelminthic drug discovery, novel drug screening tools such as isothermal microcalorimetry (IMC) have been tested with great potential. In this study, we used a novel microcalorimeter, the calScreener™, to study the viability on the hookworms Necator americanus and Ancylostoma ceylanicum as well as the whipworm Trichuris muris. Significant heat flow signals could be obtained with already one adult worm per channel for all three species. High-amplitude oscillations were observed for the hookworms; however, adult T. muris showed a twofold heat flow decrease during the first 24 h. Antinematodal effects of ivermectin and levamisole at 1, 10, and 100 μg/ml were evaluated on adult N. americanus and A. ceylanicum. Levamisole-treated hookworms showed a decline in heat flow and oscillation amplitude in a dose-response manner. Heat flow for ivermectin-treated hookworms increased proportionally with increased concentrations of ivermectin, though the wavelet analysis showed an opposite trend as observed by flatter wavelets. In conclusion, the calScreener™ is an excellent tool to study drug effects on intestinal hookworms at the adult worm stage as it offers a lower detection limit than other IMC devices and the possibility to monitor worm viability online.

  5. Cloning and expression study of the lobster (Homarus americanus) vitellogenin: Conservation in gene structure among decapods.

    PubMed

    Tiu, Shirley Hiu Kwan; Hui, Ho-Lam; Tsukimura, Brian; Tobe, Stephen S; He, Jian-Guo; Chan, Siu-Ming

    2009-01-01

    This study reports the molecular characterization of the vitellogenin (Vg) of the lobster, Homarus americanus. Based on the annual collection of female lobsters, vitellogenesis commences in early March and continues through to September of each year. Using an antibody to vitellin of the lobster, H. americanus, several immunoreactive ovarian proteins were initially identified by Western blot analysis. The 80kDa protein contained the amino acid sequence APWGGNTPRC, identified subsequently by cDNA cloning to be identical to the lobster Vg. In common with the shrimp Metapenaeus ensis and crab Charybdis feriatus, the lobster HaVg1 gene comprises 14 introns and 15 exons. The deduced HaVg1 precursor is most similar to the Vg of the crayfish Cherax quadricarinatus (57%), followed by M. ensis (40-43% identity) and C. feriatus (38%). The results from genomic and RT-PCR cloning also confirmed the presence of multiple Vg genes in lobster. At early reproductive stages, the hepatopancreas HaVg1 transcript levels are low but increased to a maximum in animals with mature oocytes. The ovary, however, also expressed low levels of HaVg1. Using in vitro explant culture, treatment of hepatopancreas fragments with farnesoic acid or 20-hydroxyecdysone resulted in a significant stimulation in HaVg1 expression. From this study, it appears that Vg gene organization and expression pattern in decapods is highly conserved. Similar endocrine mechanisms may govern the process of vitellogenesis across the decapods.

  6. The epidemiology and population biology of Necator americanus infection in a rural community in Zimbabwe.

    PubMed

    Bradley, M; Chandiwana, S K; Bundy, D A; Medley, G F

    1992-01-01

    Baseline data from an epidemiological study of hookworm infection in a rural community in Zimbabwe are presented. The infection status of an age-stratified sample of the community was assessed using anthelmintic expulsion techniques. Necator americanus was the only helminth parasite found to be present. The age-prevalence and intensity profiles rose asymptotically to an adult prevalence of about 80% and adult mean burden of 7.7 worms per host. The overall mean burden was 4.8 worms per host. The frequency distribution of N. americanus was overdispersed and well described by the negative binomial distribution with a value for the aggregation parameter, k, of 0.346. Separate estimates of k were lower in males and older hosts. The distribution patterns were difficult to reconcile with any simple process of age-dependent acquisition of an effective immune response. A significant negative correlation was recorded between per caput fecundity and worm burden, providing evidence for a density-dependent regulation of female worm fecundity. The basic reproductive rate (R0 congruent to 2) was found to be similar to estimates from other geographical areas.

  7. Phytoremediation of two types of sediment contaminated with Zn by Schoenoplectus americanus.

    PubMed

    Arreghini, Silvana; de Cabo, Laura; Fabrizio de Iorio, Alicia

    2006-01-01

    The effect of different sediments on growth, Zn uptake, Zn plant distribution, and morphometric variables of Schoenoplectus americanus were investigated under controlled conditions. Two types of sediments were assayed: from a large natural levee (LS) and alluvial sediments (AS), the former with lower organic matter (OM) and nutrients content than AS, without and with added Zn (2500 microg Zn/g air-dry sediment). Zinc partition in sediment was determined. Increases in water conductivity and Zn concentrations in water and sediments were observed in artificially contaminated treatments. Plants showed a lower above ground growth rate, height, and width of shoots, and a higher Zn concentration in shoots and rhizomes. In the contaminated treatments, AS treatment showed lower Zn concentration in water and higher Zn concentration in sediments (total, exchangeable, and OM fractions) than LS treatment, due to Zn displacement from floodwater to sediments. The presence of a high level of OM and nutrients also increased aboveground biomass growth, whereas it decreased Zn concentration in shoots. Although the translocation factor increased with Zn addition, it was lower in AS treatment Sediments of AS treatments are a suitable environment for growth of S. americanus, which partially compensates the toxic effects of Zn. Our results provide an encouraging basis for planning larger scale experiments to test the role of OM and nutrients in improving phytoremediation.

  8. Structure of monomeric Na-GST-3, a glutathione S-transferase from the major human hookworm parasite Necator americanus.

    PubMed

    Kelleher, Alan; Zhan, Bin; Asojo, Oluwatoyin A

    2013-08-01

    Necator americanus is the major cause of human hookworm infection, which is a global cause of anemia in the developing world. Ongoing efforts to control hookworm infection include the identification of candidate vaccine antigens as well as potential therapeutic targets from the infective L3 larval stages and adult stages of the parasite. One promising family of proteins are the adult-stage-secreted cytosolic glutathione S-transferases (GSTs). Nematode GSTs facilitate the inactivation and degradation of a variety of electrophilic substrates (drugs) via the nucleophilic addition of reduced glutathione. Parasite GSTs also play significant roles in multi-drug resistance and the modulation of host immune defense mechanisms. Here, the structure of Na-GST-3, one of three GSTs secreted by adult-stage N. americanus, is reported. Unlike most GST structures, the Na-GST-3 crystal contains a monomer in the asymmetric unit. However, the monomer forms a prototypical GST dimer across the crystallographic twofold. A glutathione from the fermentation process is bound to the monomer. The overall binding cavity of Na-GST-3 is reminiscent of that of other N. americanus GSTs and is larger and capable of binding a wider array of ligands than GSTs from organisms that have other major detoxifying mechanisms. Furthermore, despite having low sequence identity to the host GST, Na-GST-3 has a greater tertiary-structure similarity to human sigma-class GST than was observed for the other N. americanus GSTs.

  9. Trichinella Surveillance in Black Bears ( Ursus americanus ) from the Dehcho Region, Northwest Territories, Canada, 2002-15.

    PubMed

    Larter, Nicholas C; Elkin, Brett T; Forbes, Lorry B; Wagner, Brent; Allaire, Danny G

    2017-04-01

    We used muscle digestion to test black bears ( Ursus americanus ) from the southwestern Northwest Territories, Canada, for Trichinella. Results showed a prevalence of 4.1%. Some bears had infection intensities of more than one larva per gram of muscle tissue; this level in meat is considered to pose a human consumption safety risk.

  10. Biomarker analysis of American toad (Anaxyrus americanus) and grey tree frog (Hyla versicolor) tadpoles following exposure to atrazine.

    EPA Science Inventory

    The objective of the current study was to use a biomarker-based approach to investigate the influence of atrazine exposure on American toad (Anaxyrus americanus) and grey tree frog (Hyla versicolor) tadpoles. Atrazine is one of the most frequently detected herbicides in environme...

  11. Isolation and characterization of new genetic types of toxoplasma gondii and prevalence of trichinella murrelli from black bear (Ursus americanus)

    USDA-ARS?s Scientific Manuscript database

    Black bears (Ursus americanus) are hosts for two important zoonotic parasites, Toxoplasma gondii and Trichinella spp. and bears are hunted for human consumption in the USA. Little is known of the genetic diversity of T. gondii circulating in wildlife. In the present study, antibodies to T. gondii we...

  12. Biomarker analysis of American toad (Anaxyrus americanus) and grey tree frog (Hyla versicolor) tadpoles following exposure to atrazine.

    EPA Science Inventory

    The objective of the current study was to use a biomarker-based approach to investigate the influence of atrazine exposure on American toad (Anaxyrus americanus) and grey tree frog (Hyla versicolor) tadpoles. Atrazine is one of the most frequently detected herbicides in environme...

  13. The hidden history of the snowshoe hare, Lepus americanus: extensive mitochondrial DNA introgression inferred from multilocus genetic variation.

    PubMed

    Melo-Ferreira, José; Seixas, Fernando A; Cheng, Ellen; Mills, L Scott; Alves, Paulo C

    2014-09-01

    Hybridization drives the evolutionary trajectory of many species or local populations, and assessing the geographic extent and genetic impact of interspecific gene flow may provide invaluable clues to understand population divergence or the adaptive relevance of admixture. In North America, hares (Lepus spp.) are key species for ecosystem dynamics and their evolutionary history may have been affected by hybridization. Here we reconstructed the speciation history of the three most widespread hares in North America - the snowshoe hare (Lepus americanus), the white-tailed jackrabbit (L. townsendii) and the black-tailed jackrabbit (L. californicus) - by analysing sequence variation at eight nuclear markers and one mitochondrial DNA (mtDNA) locus (6240 bp; 94 specimens). A multilocus-multispecies coalescent-based phylogeny suggests that L. americanus diverged ~2.7 Ma and that L. californicus and L. townsendii split more recently (~1.2 Ma). Within L. americanus, a deep history of cryptic divergence (~2.0 Ma) was inferred, which coincides with major speciation events in other North American species. While the isolation-with-migration model suggested that nuclear gene flow was generally rare or absent among species or major genetic groups, coalescent simulations of mtDNA divergence revealed historical mtDNA introgression from L. californicus into the Pacific Northwest populations of L. americanus. This finding marks a history of past reticulation between these species, which may have affected other parts of the genome and influence the adaptive potential of hares during climate change.

  14. Production and characterization of recombinant vitellogenesis-inhibiting hormone from the American lobster Homarus americanus.

    PubMed

    Ohira, Tsuyoshi; Okumura, Takuji; Suzuki, Michio; Yajima, Yosuke; Tsutsui, Naoaki; Wilder, Marcy N; Nagasawa, Hiromichi

    2006-06-01

    Recombinant peptides related to vitellogenesis-inhibiting hormone (VIH) of the American lobster Homarus americanus were expressed in bacterial cells, and then purified after being allowed to refold. Biological activities of the recombinant VIHs having an amidated C-terminus (rHoa-VIH-amide) and a free carboxyl-terminus (rHoa-VIH-OH) were examined using an ovarian fragment incubation system derived from the kuruma prawn, Marsupenaeus japonicus. The rHoa-VIH-amide significantly reduced vitellogenin mRNA levels in the ovary, while rHoa-VIH-OH had no effect. This is the first report that describes the production of a crustacean VIH having biological activity and the importance of the C-terminal amidation for its vitellogenesis-inhibiting activity.

  15. Laryngeal squamous cell carcinoma in a North American black bear (Ursus americanus).

    PubMed

    Rotstein, David S; Govett, Pamela; Wolfe, Barbara

    2005-09-01

    A 10-yr-old female black bear (Ursus americanus) at the North Carolina Zoological Park presented with a 2-wk history of intermittent coughing and stertor. The animal was anesthetized for examination, and at intubation, a large mass associated with the tonsils and larynx was observed obstructing the airway. Cardiopulmonary collapse occurred during the procedure, and efforts at resuscitation were ineffective. At necropsy, an 8 cm times 6 cm times 5 cm mass was present in the larynx, infiltrating the epiglottis and obstructing the airway. Regional lymph nodes were mildly enlarged and contained tan inspissated substance. Histologically, the neoplasm was composed of nests of keratinizing squamous epithelial cells with evidence of lymphatic invasion and metastases to regional lymph nodes.

  16. Naturally occurring bacteraemia in American lobsters, Homarus americanus Milne-Edwards, in Long Island Sound.

    PubMed

    Bartlett, S L; Wooster, G A; Sokolowski, M S; Dove, A D M; Bowser, P R

    2008-01-01

    The health status of the American lobster, Homarus americanus Milne-Edwards, in Long Island Sound (LIS) has been in decline, with seasonal mortality events occurring since 1998. In order to assess the potential effects of environmental conditions on lobster health via haemolymph analysis, lobsters collected from various sites in LIS were examined and sampled while concurrent environmental data (water temperature, salinity and dissolved oxygen) were recorded. The pH of the haemolymph of each lobster was tested, followed by a collection of haemolymph for serum biochemistry analysis and bacterial culture. This report focuses on the results of the bacterial sampling. The majority of bacteria cultured were opportunistic pathogens commonly found in the environment, including some that are associated with sewage and pollution. The prevalence of bacteraemia was correlated with the site of collection, the month in which the lobsters were sampled, and water temperature.

  17. Sublethal abnormalities in embryos of winter flounder, Psuedopleuronectes americanus, from Long Island Sound

    SciTech Connect

    Perry, D.M.; Hughes, J.B.; Herbert, A.T. )

    1991-09-01

    Sublethal abnormalities were examined in developing embryos of the winter flounder, Pseudopleuronectes americanus, as part of a study of its early reproductive success in Long Island Sound and two sites in Boston Harbor. These sites represented varying levels of anthropogenic contamination that were possibly affecting reproduction, as ascertained by chromosomal abnormalities and lowered developmental rates in the embryos. Effort was focused on examination of blastula and tail-bud embryos from field-captured females spawned at the laboratory. Abnormalities observed included evidence of cytotoxicity and chromosome damage. Embryos of fish New Haven were usually the most aberrant, while embryos from other sites, notably Hempstead, Shoreham, and both Boston Harbor stations, showed subtle indications of abnormality.

  18. 'Candidatus Liberibacter americanus', associated with citrus huanglongbing (greening disease) in São Paulo State, Brazil.

    PubMed

    Teixeira, Diva do Carmo; Saillard, Colette; Eveillard, Sandrine; Danet, Jean Luc; da Costa, Paulo Inácio; Ayres, Antonio Juliano; Bové, Joseph

    2005-09-01

    , were found to have identical or almost identical sequences. In contrast, the intergenic regions of the SPS-HLB liberibacter, 'Ca. L. asiaticus' and 'Ca. L. africanus' had quite different sequences, with similarity between 66.0 and 79.5%. These results confirm that the SPS-HLB liberibacter is a novel species for which the name 'Candidatus Liberibacter americanus' is proposed. Like the African and the Asian liberibacters, the 'American' liberibacter is restricted to the sieve tubes of the citrus host. The liberibacter could also be detected by PCR amplification of the 16S rRNA gene in Diaphorina citri, the psyllid vector of 'Ca. L. asiaticus', suggesting that this psyllid is also a vector of 'Ca. L. americanus' in SPS. 'Ca. L. americanus' was detected in 216 of 218 symptomatic leaf samples from 47 farms in 35 municipalities, while 'Ca. L. asiaticus' was detected in only 4 of the 218 samples, indicating that 'Ca. L. americanus' is the major cause of HLB in SPS.

  19. Identification and cardiotropic actions of sulfakinin peptides in the American lobster Homarus americanus.

    PubMed

    Dickinson, Patsy S; Stevens, Jake S; Rus, Szymon; Brennan, Henry R; Goiney, Christopher C; Smith, Christine M; Li, Lingjun; Towle, David W; Christie, Andrew E

    2007-07-01

    In arthropods, a group of peptides possessing a -Y((SO3H))GHM/LRFamide carboxy-terminal motif have been collectively termed the sulfakinins. Sulfakinin isoforms have been identified from numerous insect species. In contrast, members of this peptide family have thus far been isolated from just two crustaceans, the penaeid shrimp Penaeus monodon and Litopenaeus vannamei. Here, we report the identification of a cDNA encoding prepro-sulfakinin from the American lobster Homarus americanus. Two sulfakinin-like sequences were identified within the open-reading frame of the cDNA. Based on modifications predicted by peptide modeling programs, and on homology to the known isoforms of sulfakinin, particularly those from shrimp, the mature H. americanus sulfakinins were hypothesized to be pEFDEY((SO3H))GHMRFamide (Hoa-SK I) and GGGEY((SO3H))DDY((SO3H))GHLRFamide (Hoa-SK II). Hoa-SK I is identical to one of the previously identified shrimp sulfakinins, while Hoa-SK II is a novel isoform. Exogenous application of either synthetic Hoa-SK I or Hoa-SK II to the isolated lobster heart increased both the frequency and amplitude of spontaneous heart contractions. In preparations in which spontaneous contractions were irregular, both peptides increased the regularity of the heartbeat. Our study provides the first molecular characterization of a sulfakinin-encoding cDNA from a crustacean, as well as the first demonstration of bioactivity for native sulfakinins in this group of arthropods.

  20. Structure of a two-CAP-domain protein from the human hookworm parasite Necator americanus

    SciTech Connect

    Asojo, Oluwatoyin A.

    2011-05-01

    The first structure of a two-CAP-domain protein, Na-ASP-1, from the major human hookworm parasite N. americanus refined to a resolution limit of 2.2 Å is presented. Major proteins secreted by the infective larval stage hookworms upon host entry include Ancylostoma secreted proteins (ASPs), which are characterized by one or two CAP (cysteine-rich secretory protein/antigen 5/pathogenesis related-1) domains. The CAP domain has been reported in diverse phylogenetically unrelated proteins, but has no confirmed function. The first structure of a two-CAP-domain protein, Na-ASP-1, from the major human hookworm parasite Necator americanus was refined to a resolution limit of 2.2 Å. The structure was solved by molecular replacement (MR) using Na-ASP-2, a one-CAP-domain ASP, as the search model. The correct MR solution could only be obtained by truncating the polyalanine model of Na-ASP-2 and removing several loops. The structure reveals two CAP domains linked by an extended loop. Overall, the carboxyl-terminal CAP domain is more similar to Na-ASP-2 than to the amino-terminal CAP domain. A large central cavity extends from the amino-terminal CAP domain to the carboxyl-terminal CAP domain, encompassing the putative CAP-binding cavity. The putative CAP-binding cavity is a characteristic cavity in the carboxyl-terminal CAP domain that contains a His and Glu pair. These residues are conserved in all single-CAP-domain proteins, but are absent in the amino-terminal CAP domain. The conserved His residues are oriented such that they appear to be capable of directly coordinating a zinc ion as observed for CAP proteins from reptile venoms. This first structure of a two-CAP-domain ASP can serve as a template for homology modeling of other two-CAP-domain proteins.

  1. Goosefish Lophius americanus fecundity and spawning frequency, with implications for population reproductive potential.

    PubMed

    McBride, R S; Johnson, A K; Lindsay, E K; Walsh, H J; Richards, R A

    2017-02-23

    To improve knowledge of goosefish Lophius americanus' reproductive biology, females were collected during 2009-2012 from the Mid-Atlantic Bight shelf region of the U.S. east coast. Batch fecundity increased with total length (LT ), from 229 100 to 2 243 300 mature oocytes per female (LT range: 55·5-112 cm; n = 54). This estimate of fecundity at LT is lower than one derived from a sample collected during 1982-1985. Examination of whole oocyte diameters in different months indicated that L. americanus is a serial spawner, releasing more than one egg veil per spawning season, as suspected or observed for other Lophius species. Seasonality of spawning was evident from whole oocytes and gonad histology, and from larval fish surveys spanning the U.S. north-east shelf, and confirmed a protracted (c. 6 months) spawning period. Peak spawning activity progressed northward from spring to autumn. The population-level implications of these results were explored by estimating population reproductive potential (PRP ), which considered the value of both current and future per capita reproduction using decade-specific age structure and fecundity at length. PRP is now more than 50% lower compared with the historical period (1982-1985), a result of the lower proportions of large females and reduced fecundity across all sizes. Mechanisms that could explain this loss of stock productivity are fishing-induced size-age truncation or regime shifts in egg production caused by changes in energy density of common forage species.

  2. A transcriptomic analysis of American lobster (Homarus americanus) immune response during infection with the bumper car parasite Anophryoides haemophila.

    PubMed

    Clark, K Fraser; Acorn, Adam R; Greenwood, Spencer J

    2013-06-01

    Anophryoides haemophila is an important protistan parasite of American lobster, Homarus americanus, as it has been found to infect lobsters in the wild as well as causing major losses of lobsters maintained in commercial holding facilities. Expression of over 14,500 H. americanus hepatopancreatic genes were monitored during an A. haemophila infection challenge in order to elucidate molecular mechanisms involved in the lobster immune response. One hundred and forty-five genes were found to be differentially expressed during infection. For many genes, this study is the first to link their expression to an immune response to a known lobster pathogen. Several of the genes have previously been linked to crustacean or invertebrate immune response including: several anti-lipopolysaccharide factor isoforms (ALFHa), acute phase serum amyloid protein A (SAA), a serine protease inhibitor, a toll-like receptor, several haemocyanin subunits, phagocyte signaling-impaired protein, vitelline membrane outer layer protein-1, trypsin, and a C-type lectin receptor. Microarray results were verified using RT-qPCR and agreement was good between the two methods. The expression of six ALFHa isoforms was monitored via microarray where ALFHa-1, ALFHa-2, ALFHa-4 and ALFHa-6 were differentially expressed while ALFHa-3 and ALFHa7 were not. RT-qPCR analysis confirmed that ALFHa-1, ALFHA-2 and ALFHa-4 expression increased during infection with a peak at 5-7weeks for ALFHa-1 and 10weeks for ALFHa-2 and ALFHa-4. This suggests that different ALFHa isoforms are temporally expressed during A. haemophila infection. Importantly, these results provide evidence that different ALFHa isoforms have more significant roles in responding to A. haemophila infection. Significant increases in SAA gene expression were also found, corroborating previous findings of increased SAA expression during Aerococcus viridans infections; highlighting the importance of SAA as a marker of H. americanus immune activation and

  3. Purification and amino acid composition of a peptide with molt-inhibiting activity from the lobster, Homarus americanus.

    PubMed

    Chang, E S; Bruce, M J; Newcomb, R W

    1987-01-01

    A peptide was isolated and purified from sinus glands of the lobster, Homarus americanus, that was able to decrease circulating titers of ecdysteroids and increase the molt interval of eyestalk-ablated juvenile lobsters. This molt-inhibiting activity was demonstrated to consist of two very closely related peptides by means of high-performance liquid chromatography and gel electrophoresis. By means of amino acid analyses, a molecular weight of approximately 8700 was obtained.

  4. On the population development of the introduced razor clam Ensis americanus near the island of Sylt (North Sea)

    NASA Astrophysics Data System (ADS)

    Armonies, W.; Reise, K.

    1998-09-01

    The American razor clam Ensis americanus (= E. directus) was introduced into the eastern North Sea in the late 1970s. By larval and poslarval drifting the species rapidly extended its distribution, now ranging from the English Channel to the Kattegat. Near the island of Sylt in the eastern North Sea it has been recorded since 1979. Recruitment was rather irregular, with about six strong year-classes within two decades. Growth seems comparable with populations in its native range (Atlantic North America). Although present in the lower intertidal zone, maximum densities occurred in shallow subtidal sand with a biomass similar to that of dense beds of native cockles and mussels in the adjacent intertidal zone. Ensis americanus established in otherwise sparsely faunated sand (channels exposed to strong currents) as well as in dense infaunal assemblages (lower intertidal and subtidally). There were no significant interactions with resident species. In dense beds of razor clams, however, fine sediment particles accumulated which may have altered abundances of polychaetes. In spite of high annual variability, E. americanus has become a prominent component of the macrobenthos in shallow subtidal sands of the North Sea.

  5. First report of Taenia arctos (Cestoda: Taeniidae) from grizzly (Ursus arctos horribilis) and black bears (Ursus americanus) in North America.

    PubMed

    Catalano, Stefano; Lejeune, Manigandan; Verocai, Guilherme G; Duignan, Pádraig J

    2014-04-01

    The cestode Taenia arctos was found at necropsy in the small intestine of a grizzly (Ursus arctos horribilis) and a black bear (Ursus americanus) from Kananaskis Country in southwestern Alberta, Canada. The autolysis of the tapeworm specimens precluded detailed morphological characterization of the parasites but molecular analysis based on mitochondrial DNA cytochrome c oxidase subunit 1 gene confirmed their identity as T. arctos. This is the first report of T. arctos from definitive hosts in North America. Its detection in Canadian grizzly and black bears further supports the Holarctic distribution of this tapeworm species and its specificity for ursids as final hosts. Previously, T. arctos was unambiguously described at its adult stage in brown bears (Ursus arctos arctos) from Finland, and as larval stages in Eurasian elk (Alces alces) from Finland and moose (Alces americanus) from Alaska, USA. Given the morphological similarity between T. arctos and other Taenia species, the present study underlines the potential for misidentification of tapeworm taxa in previous parasitological reports from bears and moose across North America. The biogeographical history of both definitive and intermediate hosts in the Holarctic suggests an ancient interaction between U. arctos, Alces spp., and T. arctos, and a relatively recent host-switching event in U. americanus.

  6. Anti-lipopolysaccharide factors in the American lobster Homarus americanus: Molecular characterization and transcriptional response to Vibrio fluvialis challenge

    PubMed Central

    Beale, K.M.; Towle, D.W.; Jayasundara, N.; Smith, C.M.; Shields, J.D.; Small, H.J.; Greenwood, S.J.

    2008-01-01

    Two partial mRNA sequences predicted to encode anti-lipopolysaccharide factors (ALFs) were identified among expressed sequence tags generated from the American lobster Homarus americanus and complete cDNA sequences were obtained from library clones. Comparison of the translated amino acid sequences to those publicly available confirmed similarity to arthropod anti-lipopolysaccharide factors. Both protein sequences, designated ALFHa-1 and ALFHa-2, contained an N-terminal signal peptide and two half-cysteines participating in a disulfide bridge, features conserved in other ALFs. Predicted secondary structures were similar to that described for the ALF from the horseshoe crab Limulus polyphemus. As part of an exploratory study of immunity in H. americanus, lobsters were injected with the bacterium Vibrio fluvialis and gill, hematopoietic, and hepatopancreas tissues were sampled for analysis of gene expression of ALFHa-1 and ALFHa-2 by quantitative PCR. The relative abundance of ALFHa-2 mRNA was not significantly affected by Vibrio injection in any of the three tissues tested. In contrast, ALFHa-1 mRNA levels in gills were increased by the treatment some 17-fold. Our results support a molecularly specific regulation of antimicrobial proteins in response to bacterial infection in H. americanus. PMID:19956341

  7. Analysis of gene expression in Homarus americanus larvae exposed to sublethal concentrations of endosulfan during metamorphosis.

    PubMed

    Bauer, Megan; Greenwood, Spencer J; Clark, K Fraser; Jackman, Paula; Fairchild, Wayne

    2013-12-01

    Agricultural pesticide runoff has been suspected as the cause of numerous fish kills in rivers throughout Prince Edward Island but the impact on the surrounding marine environment is unknown. Endosulfan, an organochlorine pesticide, is a potent neurotoxin and molt inhibitor used to combat the Colorado potato beetle however it has the potential to affect non-target organisms including the American lobster (Homarus americanus). Metamorphosis is a critical stage of development and the effects of contaminant exposure during this time are largely unknown in lobster. A 14day endosulfan exposure was performed to identify the effects on survival, development and gene expression in lobster larvae during metamorphosis; all of which were predicted to be negatively impacted. The higher endosulfan concentrations resulted in greater mortality and a significant increase in the number of days required to reach metamorphosis in surviving animals. A custom made H. americanus microarray was used for monitoring the changes in expression of 14,592 genes at the termination of the exposure. Genes with >1.5 fold change and identified as being significant at p<0.05 using one-way ANOVA were selected for further analysis. A total of 707 genes were identified as being significantly differentiated, however with only ~40% annotation of the array, the majority of these genes were unknown. Annotated genes of interest were involved in many processes: development, metabolism, immunity and oxidative stress response and gene regulation. Nine genes of interest (histone H1, farnesoic acid O-methyltransferase, cuticle protein, glutathione S-transferase, thioredoxin, NADH dehydrogenase, ecdysone nuclear receptor Fushi tarazu F1 (FTZ-F1), ferritin and ecdysone inducible protein E75 (EIP-E75)) were selected for RT-qPCR validation of the microarray results. The RT-qPCR method was more sensitive than the microarray yet detected similar expression patterns. The two highest endosulfan concentrations resulted

  8. Serosurvey for selected pathogens in free-ranging American black bears (Ursus americanus) in Maryland, USA.

    PubMed

    Bronson, Ellen; Spiker, Harry; Driscoll, Cindy P

    2014-10-01

    American black bears (Ursus americanus) in Maryland, USA, live in forested areas in close proximity to humans and their domestic pets. From 1999 to 2011, we collected 84 serum samples from 63 black bears (18 males; 45 females) in five Maryland counties and tested them for exposure to infectious, including zoonotic, pathogens. A large portion of the bears had antibody to canine distemper virus and Toxoplasma gondii, many at high titers. Prevalences of antibodies to zoonotic agents such as rabies virus and to infectious agents of carnivores including canine adenovirus and canine parvovirus were lower. Bears also had antibodies to vector-borne pathogens common to bears and humans such as West Nile virus, Borrelia burgdorferi, Rickettsia rickettsii, and Anaplasma phagocytophilum. Antibodies were detected to Leptospira interrogans serovars Pomona, Icterohaemorrhagiae, Canicola, Grippotyphosa, and Bratislava. We did not detect antibodies to Brucella canis or Ehrlichia canis. Although this population of Maryland black bears demonstrated exposure to multiple pathogens of concern for humans and domesticated animals, the low levels of clinical disease in this and other free-ranging black bear populations indicate the black bear is likely a spillover host for the majority of pathogens studied. Nevertheless, bear populations living at the human-domestic-wildlife interface with increasing human and domestic animal exposure should continue to be monitored because this population likely serves as a useful sentinel of ecosystem health.

  9. Sulfate uptake by crustacean hepatopancreatic brush border membrane vesicles. [Homarus americanus

    SciTech Connect

    Gerencser, G.A.; Cattey, M.A; Ahearn, G.A. Univ. of Hawaii, Honolulu )

    1990-02-26

    Purified brush border membrane vesicles (BBMV) were prepared from Atlantic lobster (Homarus americanus) hepatopancreas using differential centrifugation and Mg{sup +2} precipitation techniques. Uptake of 0.1 mM {sup 35}SO{sub 4}{sup {minus}2} was stimulated by pre-loading vesicles with Cl{sup {minus}} leading to a transient accumulation of isotope more than twice that at equilibrium. Pre-loading with HCO{sub 3}{sup {minus}} or gluconate had no effect on sulfate uptake. No stimulation of {sup 35}SO{sub 4}{sup {minus}2} was observed in the presence of inwardly directed Na{sup +} or tetramethylammonium{sup +} gradients. Uptake of the divalent anion was strongly stimulated by inwardly directed proton gradients (pH{sub o} < pH{sub i}) and markedly inhibited by outwardly directed proton gradients (pH{sub o} > pH{sub i}). {sup 35}SO{sub 4}{sup {minus}2}/Cl{sup {minus}} exchange was enhanced by imposing a transmembrane inside positive K{sup +} diffusion potential and inhibited by a membrane potential of the opposite polarity (K{sup +}/valinomycin). Results suggest the presence of a proton-dependent, electrogenic anion antiport mechanism in BBMV isolated from the crustacean hepatopancreas.

  10. Electrogenic sulfate uptake by crustacean hepatopancreatic basolateral membrane vesicles. [Homarus americanus

    SciTech Connect

    Cattey, M.A.; Gerencser, G.A.; Aheam, G.A. Univ. of Florida, Gainesville )

    1990-02-26

    Basolateral membrane vesicles (BLMV) were isolated from Atlantic lobster (Homarus americanus) hepatopancreas and purified by discontinuous sucrose gradient centrifugation. BLMV prepared in this fashion were osmotically reactive exhibiting linear dependence of vesicular {sup 35}SO{sub 4}{sup {minus}2} uptake to increasing external osmotic pressure with negligible non-specific isotope binding. Under short circuited conditions (valinomycin/K{sup +}) BLMV responded to either a HCO{sub 3}{sup {minus}} gradient directed out or equilibrated HCO{sub 3}{sup {minus}} (10 mM) by displaying short term accumulation of sulfate above that of equilibrium. Uptake of divalent anion was unaffected by an inwardly directed transmembrane Na{sup +} or tetramethylammonium{sup +} gradient. {sup 35}SO{sub 4}{sup {minus}2}/HCO{sub 3}{sup {minus}} exchange in the presence of valinomycin was stimulated by transient inside positive K{sup +} diffusion potentials and inhibited by transient inside negative K{sup +} diffusion potentials. The role of electrogenic anion exchange by hepatopancreas BLMV in transcellular sulfate transport is discussed.

  11. Temporal dynamics of genetic variability in a mountain goat (Oreamnos americanus) population.

    PubMed

    Ortego, Joaquín; Yannic, Glenn; Shafer, Aaron B A; Mainguy, Julien; Festa-Bianchet, Marco; Coltman, David W; Côté, Steeve D

    2011-04-01

    The association between population dynamics and genetic variability is of fundamental importance for both evolutionary and conservation biology. We combined long-term population monitoring and molecular genetic data from 123 offspring and their parents at 28 microsatellite loci to investigate changes in genetic diversity over 14 cohorts in a small and relatively isolated population of mountain goats (Oreamnos americanus) during a period of demographic increase. Offspring heterozygosity decreased while parental genetic similarity and inbreeding coefficients (F(IS) ) increased over the study period (1995-2008). Immigrants introduced three novel alleles into the population and matings between residents and immigrants produced more heterozygous offspring than local crosses, suggesting that immigration can increase population genetic variability. The population experienced genetic drift over the study period, reflected by a reduced allelic richness over time and an 'isolation-by-time' pattern of genetic structure. The temporal decline of individual genetic diversity despite increasing population size probably resulted from a combination of genetic drift due to small effective population size, inbreeding and insufficient counterbalancing by immigration. This study highlights the importance of long-term genetic monitoring to understand how demographic processes influence temporal changes of genetic diversity in long-lived organisms.

  12. Sarcocystis oreamni, n. sp. (Apicomplexa: Sarcocystidae) from the mountain goat (Oreamnos americanus).

    PubMed

    Calero-Bernal, Rafael; Van Wilpe, Erna; White, Kevin; Verma, Shiv K; Cerqueira-Cézar, Camila K; Dubey, Jitender P

    2015-11-01

    Numerous species of Sarcocystis have been reported from wild ruminants, but none has been named from the Rocky Mountain goat (Oreamnos americanus). Mature sarcocysts were found in frozen muscle samples of three of seven mountain goats from Alaska, USA. Two morphological types of sarcocysts were found; one had Sarcocystis cornagliai-like sarcocysts, previously named from the Alpine ibex (Capra ibex) from Europe. Two other goats were infected with a new species, Sarcocystis oreamni. Sarcocystis oreamni sarcocysts were microscopic with 2 μm-thick sarcocyst wall. By transmission electron microscopy, the sarcocyst wall had 1.7 μm-thick with unusual molar tooth-like villar protrusions (vp), type 29. The vp had an electron dense core and two disc-shaped plaques at the tip with fine microtubules. Bradyzoites were 8.6-9.1 μm long. Single nucleotide polymorphism (SNP) identified in 18S rRNA, and 28S rRNA loci of rDNA regions that suggested S. oreamni molecularly apart from related species. The phylogenetic analysis based on 18S rRNA and 28S rRNA sequences suggested S. oreamni is related with Sarcocystis species that employ members of the Canidae family as their definitive host.

  13. Bears "Count" Too: Quantity Estimation and Comparison in Black Bears (Ursus Americanus).

    PubMed

    Vonk, Jennifer; Beran, Michael J

    2012-07-01

    Studies of bear cognition are notably missing from the comparative record despite bears' large relative brain size and interesting status as generalist carnivores facing complex foraging challenges, but lacking complex social structures. We investigated the numerical abilities of three American black bears (Ursus Americanus) by presenting discrimination tasks on a touch-screen computer. One bear chose the larger of two arrays of dot stimuli, while two bears chose the smaller array of dots. On some trials the relative number of dots was congruent with the relative total area of the two arrays. On other trials number of dots was incongruent with area. All of the bears were above chance on trials of both types with static dots. Despite encountering greater difficulty with dots that moved within the arrays, one bear was able to discriminate numerically larger arrays of moving dots, and a subset of moving dots from within the larger array, even when area and number were incongruent. Thus, although the bears used area as a cue to guide responding, they were also able to use number as a cue. The pattern of performance was similar to that found previously with monkeys, and suggests that bears may also show other forms of sophisticated quantitative abilities.

  14. Social network analysis of mating patterns in American black bears (Ursus americanus).

    PubMed

    Moore, Jennifer A; Xu, Ran; Frank, Kenneth; Draheim, Hope; Scribner, Kim T

    2015-08-01

    Nonrandom mating can structure populations and has important implications for population-level processes. Investigating how and why mating deviates from random is important for understanding evolutionary processes as well as informing conservation and management. Prior to the implementation of parentage analyses, understanding mating patterns in solitary, elusive species like bears was virtually impossible. Here, we capitalize on a long-term genetic data set collected from black bears (Ursus americanus) (N = 2422) in the Northern Lower Peninsula (NLP) of Michigan, USA. We identified mated pairs using parentage analysis and applied logistic regression (selection) models that controlled for features of the social network, to quantify the effects of individual characteristics, and spatial and population demographic factors on mating dynamics. Logistic regression models revealed that black bear mating was associated with spatial proximity of mates, male age, the time a pair had coexisted, local population density and relatedness. Mated pairs were more likely to contain older males. On average, bears tended to mate with nearby individuals to whom they were related, which does not support the existence of kin recognition in black bears. Pairwise relatedness was especially high for mated pairs containing young males. Restricted dispersal and high male turnover from intensive harvest mortality of NLP black bears are probably the underlying factors associated with younger male bears mating more often with female relatives. Our findings illustrate how harvest has the potential to disrupt the social structure of game species, which warrants further attention for conservation and management. © 2015 John Wiley & Sons Ltd.

  15. Anaerobic oral flora in the North American black bear (Ursus americanus) in eastern North Carolina.

    PubMed

    Clarke, Elsburgh O; Stoskopf, Michael K; Minter, Larry J; Stringer, Elizabeth M

    2012-06-01

    Microbial flora can provide insight into the ecology and natural history of wildlife in addition to improving understanding of health risks. This study examines the anaerobic oral flora of hunter killed black bears (Ursus americanus) in eastern North Carolina. Oral swabs from the buccal and lingual supragingival tooth surfaces of the first and second mandibular and maxillary molars of 22 black bears were inoculated onto Brucella Blood Agar plates supplemented with hemin and vitamin K after transport from the field using reduced oxoid nutrient broth. Sixteen anaerobic bacterial species, representing nine genera were identified using the RapID ANA II Micromethod Kit system and a number of organisms grown that could not be identified with the system. The most frequently identified anaerobes were Peptostreptococcus prevotii, Streptococcus constellatus, and Porphyromonas gingivalis. The diversity in the anaerobic oral flora of black bear in eastern North Carolina suggests the importance of including these organisms in basic health risk assessment protocols and suggests a potential tool for assessment of bear/habitat interactions. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Genomic analysis of expressed sequence tags in American black bear Ursus americanus.

    PubMed

    Zhao, Sen; Shao, Chunxuan; Goropashnaya, Anna V; Stewart, Nathan C; Xu, Yichi; Tøien, Øivind; Barnes, Brian M; Fedorov, Vadim B; Yan, Jun

    2010-03-26

    Species of the bear family (Ursidae) are important organisms for research in molecular evolution, comparative physiology and conservation biology, but relatively little genetic sequence information is available for this group. Here we report the development and analyses of the first large scale Expressed Sequence Tag (EST) resource for the American black bear (Ursus americanus). Comprehensive analyses of molecular functions, alternative splicing, and tissue-specific expression of 38,757 black bear EST sequences were conducted using the dog genome as a reference. We identified 18 genes, involved in functions such as lipid catabolism, cell cycle, and vesicle-mediated transport, that are showing rapid evolution in the bear lineage Three genes, Phospholamban (PLN), cysteine glycine-rich protein 3 (CSRP3) and Troponin I type 3 (TNNI3), are related to heart contraction, and defects in these genes in humans lead to heart disease. Two genes, biphenyl hydrolase-like (BPHL) and CSRP3, contain positively selected sites in bear. Global analysis of evolution rates of hibernation-related genes in bear showed that they are largely conserved and slowly evolving genes, rather than novel and fast-evolving genes. We provide a genomic resource for an important mammalian organism and our study sheds new light on the possible functions and evolution of bear genes.

  17. Right paw foraging bias in wild black bear (Ursus americanus kermodei).

    PubMed

    Reimchen, T E; Spoljaric, M A

    2011-07-01

    Using field observations of ~15 wild adult black bear (Ursus americanus kermodei) foraging on a salmon stream during two autumns on the central coast of British Columbia, we tested for laterality of forelimb use during lunging and during handling of salmon. Of 288 lunging events observed overall, 53% were non biased, 26% were right-limb biased, and 21% left-limb biased (p = .53 between left and right bias). Among six bears in which we could ascertain individual identity (182 lunging events), there was heterogeneity among individuals (p <.05) of which two were significantly right biased and one significantly left biased (p<.005). Of 186 carcass-handling (pick-up) events, 68% were right-pawed (p <.005) and there was no heterogeneity among five individually identifiable bears (p = .19). There was no forelimb laterality in adjustment of the prey in the mouth or in securing the prey to the substrate. This is the first report of task-specific behavioural lateralisation of a wild carnivore and is suggestive of a right bias (left-hemisphere dominance) in object manipulation.

  18. Liver lesions in winter flounder (Pseudopleuronectes americanus) from Jamaica Bay, New York: Indications of environmental degradation

    USGS Publications Warehouse

    Augspurger, T.P.; Herman, R.L.; Tanacredi, J.T.; Hatfield, J.S.

    1994-01-01

    Liver sections of winter flounder (Pseudopleuronectes americanus) collected from Jamaica Bay and Shinnecock Bay, New York, in 1989, were examined microscopically to determine the pervasiveness of liver lesions observed previously in Jamaica Bay winter flounder. Neoplastic lesions were not detected in fish from Jamaica Bay or the Shinnecock Bay reference site. Twenty-two percent of Jamaica Bay winter flounder examined (n = 103) had unusual vacuolization of hepatocytes and biliary pre-ductal and ductal cells (referred to hereafter as the vacuolated cell lesion). The lesion, identical to that found in 25% of Jamaica Bay winter flounder examined in 1988, has previously been identified in fishes taken from highly polluted regions of the Atlantic coast (e.g., Boston Harbor, Massachusetts, and Black Rock Harbor, Connecticut). Prevalence of the vacuolated cell lesion in winter flounder from Jamaica Bay was significantly greater (p < 0.0001) than in 102 specimens collected from Shinnecock Bay. Current scientific literature indicates vacuolated hepatocytes and cholangiocytes are chronically injured and that the extent of their deformity is consistent with the action of a hepatotoxicant. The high prevalence of vacuolated hepatocytes in Jamaica Bay winter flounder and absence of the lesion in flounder from reference sites strongly supports the hypothesis that this impairment is a manifestation of a toxic condition in at least some portions of Jamaica Bay.

  19. Seasonal variation in American black bear Ursus americanus activity patterns: Quantification via remote photography

    USGS Publications Warehouse

    Bridges, A.S.; Vaughan, M.R.; Klenzendorf, S.

    2004-01-01

    Activity pattern plasticity may serve as an evolutionary adaptation to optimize fitness in an inconstant environment, however, quantifying patterns and demonstrating variation can be problematic. For American black bears Ursus americanus, wariness and habitat inaccessibility further complicate quantification. Radio telemetry has been the primary technique used to examine activity, however, interpretation error and limitation on numbers of animals available to monitor prevent extrapolation to unmarked or untransmittered members of the population. We used remote cameras to quantify black bear activity patterns and examined differences by season, sex and reproductive class in the Alleghany Mountains of western Virginia, USA. We used 1,533 pictures of black bears taken during 1998-2002 for our analyses. Black bears generally were diurnal in summer and nocturnal in autumn with a vespertine activity peak during both seasons. Bear-hound training seasons occurred during September and may offer explanation for the observed shift towards nocturnal behaviour. We found no substantial differences in activity patterns between sex and reproductive classes. Use of remote cameras allowed us to efficiently sample larger numbers of individual animals and likely offered a better approximation of population-level activity patterns than individual-level, telemetry-based methodologies.

  20. Short- and long-term dietary effects on disease and mortality in American lobster Homarus americanus.

    PubMed

    Tlusty, Michael F; Myers, Anna; Metzler, Anita

    2008-01-24

    The American lobster Homarus americanus fishery is heavily dependent on the use of fish as bait to entice lobsters into traps. There is concern that this food supplementation is nutritionally insufficient for lobsters, but previous experiments reported conflicting results. We conducted a long-term feeding experiment in which 1 yr old American lobsters were fed one of 7 diets for a period of 352 d, a time that allowed the lobsters to molt thrice. The diets consisted of fresh frozen herring, a 'wild' diet (rock crab, mussel, and Spirulina algae), a formulated artificial diet for shrimp, paired combinations of these 3 diets or a diet formulated at the New England Aquarium (Artemia, fish and krill meal, Spirulina algae, soy lecithin, vitamins and minerals). The lobsters fed the diet of 100% fish had higher initial molting rates, but within the period of this experiment all either contracted shell disease or died. Mixed diets resulted in higher survival and a lower probability of mortality. This research demonstrated a critical time component to diet studies in lobsters. Short- and long-term impacts of diet differ. In the long term, continual high consumption rates of fish by the lobsters promote poor health in all lobsters, not just those of market size. The use of fish as bait may make lobsters more susceptible to the stress associated with environmental fluctuation, thereby leading to increased disease and mortality. This nutritional stress can be used to develop a laboratory model of shell disease in American lobsters.

  1. Elevated expression of protein biosynthesis genes in liver and muscle of hibernating black bears (Ursus americanus).

    PubMed

    Fedorov, Vadim B; Goropashnaya, Anna V; Tøien, Oivind; Stewart, Nathan C; Gracey, Andrew Y; Chang, Celia; Qin, Shizhen; Pertea, Geo; Quackenbush, John; Showe, Louise C; Showe, Michael K; Boyer, Bert B; Barnes, Brian M

    2009-04-10

    We conducted a large-scale gene expression screen using the 3,200 cDNA probe microarray developed specifically for Ursus americanus to detect expression differences in liver and skeletal muscle that occur during winter hibernation compared with animals sampled during summer. The expression of 12 genes, including RNA binding protein motif 3 (Rbm3), that are mostly involved in protein biosynthesis, was induced during hibernation in both liver and muscle. The Gene Ontology and Gene Set Enrichment analysis consistently showed a highly significant enrichment of the protein biosynthesis category by overexpressed genes in both liver and skeletal muscle during hibernation. Coordinated induction in transcriptional level of genes involved in protein biosynthesis is a distinctive feature of the transcriptome in hibernating black bears. This finding implies induction of translation and suggests an adaptive mechanism that contributes to a unique ability to reduce muscle atrophy over prolonged periods of immobility during hibernation. Comparing expression profiles in bears to small mammalian hibernators shows a general trend during hibernation of transcriptional changes that include induction of genes involved in lipid metabolism and carbohydrate synthesis as well as depression of genes involved in the urea cycle and detoxification function in liver.

  2. Behavioral response and kinetics of terrestrial atrazine exposure in American toads (bufo americanus)

    USGS Publications Warehouse

    Storrs, Mendez S.I.; Tillitt, D.E.; Rittenhouse, T.A.G.; Semlitsch, R.D.

    2009-01-01

    Amphibians in terrestrial environments obtain water through a highly vascularized pelvic patch of skin. Chemicals can also be exchanged across this patch. Atrazine (ATZ), a widespread herbicide, continues to be a concern among amphibian ecologists based on potential exposure and toxicity. Few studies have examined its impact on the terrestrial juvenile or adult stages of toads. In the current study, we asked the following questions: (1) Will juvenile American toads (Bufo americanus) avoid soils contaminated with ATZ? (2) Can they absorb ATZ across the pelvic patch? (3) If so, how is it distributed among the organs and eventually eliminated? We conducted a behavioral choice test between control soil and soil dosed with ecologically relevant concentrations of ATZ. In addition, we examined the uptake, distribution, and elimination of water dosed with 14C-labeled ATZ. Our data demonstrate that toads do not avoid ATZ-laden soils. ATZ crossed the pelvic patch rapidly and reached an apparent equilibrium within 5 h. The majority of the radiolabeled ATZ ended up in the intestines, whereas the greatest concentrations were observed in the gall bladder. Thus, exposure of adult life stages of amphibians through direct uptake of ATZ from soils and runoff water should be considered in risk evaluations. ?? 2009 Springer Science+Business Media, LLC.

  3. Bone formation is not impaired by hibernation (disuse) in black bears Ursus americanus

    USGS Publications Warehouse

    Donahue, S.W.; Vaughan, M.R.; Demers, L.M.; Donahue, H.J.

    2003-01-01

    Disuse by bed rest, limb immobilization or space flight causes rapid bone loss by arresting bone formation and accelerating bone resorption. This net bone loss increases the risk of fracture upon remobilization. Bone loss also occurs in hibernating ground squirrels, golden hamsters, and little brown bats by arresting bone formation and accelerating bone resorption. There is some histological evidence to suggest that black bears Ursus americanus do not lose bone mass during hibernation (i.e. disuse). There is also evidence suggesting that muscle mass and strength are preserved in black bears during hibernation. The question of whether bears can prevent bone loss during hibernation has not been conclusively answered. The goal of the current study was to further assess bone metabolism in hibernating black bears. Using the same serum markers of bone remodeling used to evaluate human patients with osteoporosis, we assayed serum from five black bears, collected every 10 days over a 196-day period, for bone resorption and formation markers. Here we show that bone resorption remains elevated over the entire hibernation period compared to the pre-hibernation period, but osteoblastic bone formation is not impaired by hibernation and is rapidly accelerated during remobilization following hibernation.

  4. Effects of cooking on levels of PCBs in the fillets of winter flounder (Pseudopleuronectes americanus)

    SciTech Connect

    Poston, T.M.; Durell, G.S.; Koczwara, G.; Spellacy, A.M.

    1995-08-01

    The Pacific Northwest Laboratory and Battelle Ocean Sciences performed a study to determine the effect of cooking on polychlorinated biphenyl (PCB) levels in the fillets of winter flounder (Pseudopleuronectes americanus). Broiling, pan frying, and deep frying in oil were tested on fillets from 21 fish collected from New Bedford Harbor, Massachusetts, on February 21, 1991. The evaluation involved estimating the change in PCB concentrations using a mass-balance approach that factored the change in fillet weight resulting from cooking with the changes in PCB concentration expressed on a precooked wet-weight basis. Deep frying in oil resulted in a 47% reduction in total PCB levels in fillet tissue. Additionally, deep frying caused a 40% reduction in fillet mass. Pan frying and broiling resulted in statistically in insignificant increases in total PCB levels of 15% and 17%, respectively. Fillet mass reductions resulting from pan frying and broiling were 7% and 15%, respectively. The effects of cooking on 18 individual congeners generally paralleled the results observed for total PCB. All 18 congeners were significantly reduced by deep frying. Congener Cl{sub 2}(08) also was significantly reduced by either pan frying. Congeners Cl{sub 5}(105) and Cl{sub 5}(118) showed apparent significant increases in concentrations following pan frying. Congeners Cl{sub 5}(105), Cl{sub 5}(118), and C1{sub 6}(138) showed significant increases in concentration following broiling.

  5. Experimental Infection and Detection of Necrotizing Hepatopancreatitis Bacterium in the American Lobster Homarus americanus

    PubMed Central

    Avila-Villa, Luz A.; Gollas-Galván, Teresa; Martínez-Porchas, Marcel; Mendoza-Cano, Fernando; Hernández-López, Jorge

    2012-01-01

    Necrotizing hepatopancreatitis bacterium (NHPB) is an obligated intracellular bacteria causing severe hepatopancreatic damages and mass mortalities in penaeid shrimp. The worldwide distribution of penaeid shrimp as alien species threatens the life cycle of other crustacean species. The aim of the experiment was to evaluate the possibility of experimentally infecting the American lobster (Homarus americanus) with NHPB extracted from shrimp hepatopancreas. Homogenates from infected shrimp were fed by force to lobsters. Other group of lobsters was fed with homogenates of NHPB-free hepatopancreas. After the 15th day from initial inoculation, the presence of NHPB was detected by polymerase chain reaction in feces and hepatopancreas from lobsters inoculated with infected homogenates. Necrotized spots were observed in the surface of lobster hepatopancreas. In contrast, lobsters fed on NHPB-free homogenates resulted negative for NHPB. Evidence suggests the plasticity of NHPB which can infect crustacean from different species and inhabiting diverse latitudes. Considering the results, the American lobster could be a good candidate to maintain available NHPB in vivo. PMID:22645497

  6. Esfenvalerate-induced case-abandonment in the larvae of the caddisfly (Brachycentrus americanus).

    PubMed

    Johnson, Katherine R; Jepson, Paul C; Jenkins, Jeffrey J

    2008-02-01

    Field-collected Brachycentrus americanus Banks (Trichoptera: Brachycentridae) larvae were used to investigate the relationship between esfenvalerate exposure and case-abandonment response, determine larval ability to construct a new case, and measure the change in predation risk to insects in rebuilt cases. We evaluated case-abandonment following four environmentally relevant esfenvalerate exposures, 0.05, 0.1, 0.2, and 0.4 microg/L; 48-h exposures to 0.2 and 0.4 microg/L (nominal) esfenvalerate both resulted in over 60% of larvae abandoning cases and were statistically indistinguishable. Propensity to engage in building behaviors was significantly diminished in 0.2 and 0.4 microg/L esfenvalerate-exposed insects that had abandoned cases, with less than 20% of exposed insects producing cases. Cases built by intoxicated larvae were characterized by a disorganized composition, and required half the pressure to crush versus cases built by nonexposed larvae. Pre-exposing case-building material to 1 microg/L esfenvalerate also reduced the physical strength of rebuilt cases. Larvae inhabiting weaker rebuilt cases and larvae without cases were significantly more susceptible to predation by second year Hesperoperla pacifica Banks (Plecoptera: Perlidae) stonefly nymphs than those in original cases. Overall, we concluded that small behavioral responses can have profound consequences for survival of species and reveal susceptible stages in life-cycles that can be overlooked by conventional approaches to ecological risk assessment.

  7. Effects of body temperature and hydration state on organismal performance of toads, Bufo americanus.

    PubMed

    Preest, Marion R; Pough, F Harvey

    2003-01-01

    Temperature and humidity are dominant environmental variables affecting performance of nocturnal, terrestrial amphibians. Toads are frequently active at body temperatures (T(b)) and hydration states (HS) that yield suboptimal performance. We investigated the combined effects of T(b) and HS on feeding, locomotion, and metabolism of Bufo americanus. More toads responded to the presence of prey when fully hydrated than when dehydrated, and times to orient to prey, maneuver around a barrier, and reach prey were less in hydrated than in dehydrated animals. Time to capture prey decreased with increasing T(b) in fully hydrated, but not dehydrated, toads, and hydrated animals caught prey more rapidly than did dehydrated animals. Distance traveled in 5 min and aerobic scope were affected by T(b). Generally, individuals that performed well in the feeding experiments at a particular T(b) and HS also performed well at a different T(b) and HS. The same was true for distance traveled and aerobic scope. However, within combinations of T(b) and HS, correlations between performance variables were minimal. Specialization of a particular variable resulting in high performance at a certain T(b) and HS does not appear to exact a cost in terms of performance at a different T(b) and HS.

  8. Energy expenditure during activity in the American lobster Homarus americanus: Correlations with body acceleration.

    PubMed

    Lyons, G N; Halsey, L G; Pope, E C; Eddington, J D; Houghton, J D R

    2013-10-01

    How animals manage time and expend energy has implications for survivorship. Being able to measure key metabolic costs of animals under natural conditions is therefore an important tool in behavioral ecology. One method for estimating activity-specific metabolic rate is via derived measures of acceleration, often 'overall dynamic body acceleration' (ODBA), recorded by an instrumented acceleration logger. ODBA has been shown to correlate well with rate of oxygen consumption (V˙o2) in a range of species during activity in the laboratory. This study devised a method for attaching acceleration loggers to decapod crustaceans and then correlated ODBA against concurrent respirometry readings to assess accelerometry as a proxy for activity-specific energy expenditure in a model species, the American lobster Homarus americanus. Where the instrumented animals exhibited a sufficient range of activity levels, positive linear relationships were found between V˙o2 and ODBA over 20min periods at a range of ambient temperatures (6, 13 and 20°C). Mixed effect linear models based on these data and morphometrics provided reasonably strong predictive power for estimating activity-specific V˙o2 from ODBA. These V˙o2-ODBA calibrations demonstrate the potential of accelerometry as an effective predictor of behavior-specific metabolic rate of crustaceans in the wild during periods of activity.

  9. Behavior and substrate selection during larval settling in the lobster Homarus americanus

    SciTech Connect

    Botero, L.; Atema, J.

    1982-02-01

    During the molt from third- to fourth-stage, larvae of Homarus americanus metamorphose into their adult form and pigmentation. In the course of the fourth stage, their pelagic life changes to a benthic existence. Artificial substrate choice experiments and qualitative illumination experiments show that during the early fourth stage the phototactic response reverses from positive to negative. Together with positive thigmotaxis, this results in a choice of dark crevices. Among natural substrate choices, preferential settlement occurred on macroalgal-covered rocks, followed by rocks on sand, mud, and sand. Although mud was not a preferred substrate in choice tests, the animals that chose mud and those that were presented only with mud settled successfully and were immediately efficient in their burrowing behavior, constructing U-shaped tunnels even in the center of the aquarium without using a pebble or rock as a starting point. These laboratory test confirm field observations that lobsters can successfully exploit a variety of substrates. They show that a substrate with preformed crevices is preferred for settling, but other substrates can be manipulated to make suitable burrows.

  10. Neuromuscular synapses on the dactyl opener muscle of the lobster Homarus americanus.

    PubMed

    Hamilton, Jonna; Dillaman, Richard M; Worden, Mary Kate

    2006-12-01

    The crustacean dactyl opener neuromuscular system has been studied extensively as a model system that exhibits several forms of synaptic plasticity. We report the ultrastructural features of the synapses on dactyl opener of the lobster (Homarus americanus) as determined by examination of serial thin sections. Several innervation sites supplied by an inhibitory motoneuron have been observed without nearby excitatory innervation, indicating that excitatory and inhibitory inputs to the muscle are not always closely matched. The ultrastructural features of the lobster synapses are generally similar to those described previously for the homologous crayfish muscle, with one major distinction: few dense bars are seen at the presynaptic membranes of these lobster synapses. The majority of the lobster neuromuscular synapses lack dense bars altogether, and the mean number of dense bars per synapse is relatively low. In view of the finding that the physiology of the lobster dactyl opener synapses is similar to that reported for crayfish, these ultrastructural observations suggest that the structural complexity of the synapses may not be a critical factor determining synaptic plasticity.

  11. Antimicrobial activity in the cuticle of the American lobster, Homarus americanus.

    PubMed

    Mars Brisbin, Margaret; McElroy, Anne E; Pales Espinosa, Emmanuelle; Allam, Bassem

    2015-06-01

    American lobster, Homarus americanus, continues to be an ecologically and socioeconomically important species despite a severe decline in catches from Southern New England and Long Island Sound (USA) and a high prevalence of epizootic shell disease in these populations. A better understanding of lobster immune defenses remains necessary. Cuticle material collected from Long Island Sound lobsters was found to be active against a broad spectrum of bacteria, including Gram-negative and -positive species. The antimicrobial activity was characterized by boiling, muffling, and size fractioning. Boiling did not significantly reduce activity, while muffling did have a significant effect, suggesting that the active component is organic and heat stable. Size fractioning with 3 and 10 kDa filters did not significantly affect activity. Fast protein liquid chromatography fractions were also tested for antimicrobial activity, and fractions exhibiting protein peaks remained active. MALDI mass spectrometry revealed peptide peaks at 1.6, 2.8, 4.6, and 5.6 kDa. The data presented suggest that one or several antimicrobial peptides contribute to antimicrobial activity present in the American lobster cuticle.

  12. An unusual cuticular tumor-like growth on the abdomen of a lobster, Homarus americanus.

    PubMed

    Shields, Jeffrey D; Small, Hamish J

    2013-11-01

    Tumors are rare in crustaceans, and whereas a few have been reported from the lobster Homarus americanus none have been adequately described. A lobster with an unusual, large, blue-colored tumor-like growth projecting laterally outward from the first abdominal somite was caught off Stonington, Maine, USA. The growth was rugose and covered by a relatively normal appearing cuticle with dispersed focal melanization. The underlying stroma consisted of an internal area of rescaffolded fibrous connective tissue, restructured muscle fibers, few arterioles, and an epidermal area comprised of columnar, highly vacuolated epithelial cells. No infectious pathogens or unusual inclusions were observed with microscopy and no eukaryotic pathogens were detected via molecular sequencing. Given the nature of the histology and the appearance of the growth, we identify the mass as a benign papilliform hamartoma that likely originated as a result of abnormal wound repair possibly initiated around ecdysis. This represents the first tumor-like hamartoma reported from a lobster, and the second hamartoma reported from a crustacean.

  13. Daily Rhythms of PERIOD protein in the eyestalk of the American lobster, Homarus americanus.

    PubMed

    Grabek, Katharine R; Chabot, Christopher C

    2012-01-01

    The daily rhythm of PERIOD protein (PER) expression is an integral component of the circadian clock, which is found among a broad range of animal species including fruit flies, marine mollusks and even humans. The use of antibodies directed against PER has provided a helpful tool in the discovery of PER homologues and the labeling of putative pacemaker cells, especially in animals for which an annotated genome is not readily available. In this study, DrosophilaPER antibodies were used to probe for PER in the American lobster, Homarus americanus. This species exhibits robust endogenous circadian rhythms but the circadian clock has yet to be located or characterized. PER was detected in the eyestalks of the lobster but not in the brain. Furthermore, a significant effect of the LD cycle on daily PER abundance was identified, and PER was significantly more abundant at mid dark than in early light or mid light hours. Our results suggest that PER is a part of the molecular machinery of the circadian clock located in the eyestalk of the lobster.

  14. American Lobsters (Homarus Americanus) not Surviving During Air Transport: Evaluation of Microbial Spoilage

    PubMed Central

    Tirloni, Erica; Stella, Simone; Gennari, Mario; Colombo, Fabio

    2016-01-01

    Eighteen American lobsters (Homarus americanus), dead during air transport, were analysed in order to evaluate the microbial population of meat, gills and gut: no specific studies have ever been conducted so far on the microbiological quality of American lobsters’ meats in terms of spoilage microbiota. The meat samples showed very limited total viable counts, in almost all the cases below the level of 6 Log CFU/g, while higher loads were found, as expected, in gut and gills, the most probable source of contamination. These data could justify the possibility to commercialise these not-surviving subjects, without quality concerns for the consumers. Most of the isolates resulted to be clustered with type strains of Pseudoalteromonas spp. (43.1%) and Photobacterium spp. (24.1%), and in particular to species related to the natural marine environment. The distribution of the genera showed a marked inhomogeneity among the samples. The majority of the isolates identified resulted to possess proteolytic (69.3%) and lipolytic ability (75.5%), suggesting their potential spoilage ability. The maintanance of good hygienical practices, especially during the production of ready-to-eat lobsters-based products, and a proper storage could limit the possible replication of these microorganisms. PMID:27800442

  15. Genomic analysis of expressed sequence tags in American black bear Ursus americanus

    PubMed Central

    2010-01-01

    Background Species of the bear family (Ursidae) are important organisms for research in molecular evolution, comparative physiology and conservation biology, but relatively little genetic sequence information is available for this group. Here we report the development and analyses of the first large scale Expressed Sequence Tag (EST) resource for the American black bear (Ursus americanus). Results Comprehensive analyses of molecular functions, alternative splicing, and tissue-specific expression of 38,757 black bear EST sequences were conducted using the dog genome as a reference. We identified 18 genes, involved in functions such as lipid catabolism, cell cycle, and vesicle-mediated transport, that are showing rapid evolution in the bear lineage Three genes, Phospholamban (PLN), cysteine glycine-rich protein 3 (CSRP3) and Troponin I type 3 (TNNI3), are related to heart contraction, and defects in these genes in humans lead to heart disease. Two genes, biphenyl hydrolase-like (BPHL) and CSRP3, contain positively selected sites in bear. Global analysis of evolution rates of hibernation-related genes in bear showed that they are largely conserved and slowly evolving genes, rather than novel and fast-evolving genes. Conclusion We provide a genomic resource for an important mammalian organism and our study sheds new light on the possible functions and evolution of bear genes. PMID:20338065

  16. Immobilization of black bears (Ursus americanus) with orally administered carfentanil citrate.

    PubMed

    Ramsay, E C; Sleeman, J M; Clyde, V L

    1995-07-01

    Ten black bears (Ursus americanus) were immobilized with orally administered carfentanil citrate. The total carfentanil dose was mixed with 5 to 20 ml honey and given incrementally to captive bears. The bears ranged in weight from 80 (estimated) to 233 kg. Total carfentanil doses ranged from 0.7 to 3.0 mg, resulting in dosages of 6.8 to 18.8 micrograms carfentanil/kg. Mean (+/- SD) times from estimated 80% mixture consumption to sternal recumbency, and first safe human contact were 7.7 +/- 2.3 min and 19.7 +/- 5.6 min, respectively. Undesired side effects of immobilization were muscle rigidity, bradypnea, and oxygen desaturation. All bears received diazepam to alleviate muscle rigidity and were insufflated with oxygen during immobilization. Nine immobilizations were considered satisfactory or good. The bear receiving 6.8 micrograms carfentanil/kg, the lowest dosage used, was very excited during induction and required intravenous (IV) ketamine to permit safe examination. Immobilization was reversed with 100 mg naltrexone/mg carfentanil administered (75% subcutaneous, 25% IV). Bears recovered to full mobility in 6.3 +/- 1.9 min. Five bears vomited post-recovery but no episodes of renarcotization were observed.

  17. Modulation of gene expression in heart and liver of hibernating black bears (Ursus americanus).

    PubMed

    Fedorov, Vadim B; Goropashnaya, Anna V; Tøien, Oivind; Stewart, Nathan C; Chang, Celia; Wang, Haifang; Yan, Jun; Showe, Louise C; Showe, Michael K; Barnes, Brian M

    2011-03-31

    Hibernation is an adaptive strategy to survive in highly seasonal or unpredictable environments. The molecular and genetic basis of hibernation physiology in mammals has only recently been studied using large scale genomic approaches. We analyzed gene expression in the American black bear, Ursus americanus, using a custom 12,800 cDNA probe microarray to detect differences in expression that occur in heart and liver during winter hibernation in comparison to summer active animals. We identified 245 genes in heart and 319 genes in liver that were differentially expressed between winter and summer. The expression of 24 genes was significantly elevated during hibernation in both heart and liver. These genes are mostly involved in lipid catabolism and protein biosynthesis and include RNA binding protein motif 3 (Rbm3), which enhances protein synthesis at mildly hypothermic temperatures. Elevated expression of protein biosynthesis genes suggests induction of translation that may be related to adaptive mechanisms reducing cardiac and muscle atrophies over extended periods of low metabolism and immobility during hibernation in bears. Coordinated reduction of transcription of genes involved in amino acid catabolism suggests redirection of amino acids from catabolic pathways to protein biosynthesis. We identify common for black bears and small mammalian hibernators transcriptional changes in the liver that include induction of genes responsible for fatty acid β oxidation and carbohydrate synthesis and depression of genes involved in lipid biosynthesis, carbohydrate catabolism, cellular respiration and detoxification pathways. Our findings show that modulation of gene expression during winter hibernation represents molecular mechanism of adaptation to extreme environments.

  18. A descriptive analysis of the climbing mechanics of a mountain goat (Oreamnos americanus).

    PubMed

    Lewinson, Ryan T; Stefanyshyn, Darren J

    2016-12-01

    The mountain goat (Oreamnos americanus) is one of the most extraordinary mountaineers in the animal kingdom. While observational descriptions exist to indicate factors that may influence their climbing ability, these have never been assessed biomechanically. Here, we describe whole-body motion of a mountain goat during ascent of a 45° incline based on a video recording in the Canadian Rocky Mountains, and discuss the results in a mechanical context. During the push-off phase, the hindlimb extended and the forelimb was tucked close to the torso. During the pull-up phase, the hindlimb was raised near to the torso, while the forelimb humerus seemed to "lock" in a constant position relative to the torso, allowing the elbow to be held in close proximity to the whole-body center of mass. Extension of the elbow and carpal joints resulted in a vertical translation of the center of mass up the mountain slope. Based on the observations from this naturalistic study, hypotheses for future controlled studies of mountain goat climbing mechanics are proposed. Copyright © 2016 Elsevier GmbH. All rights reserved.

  19. Idiopathic lesions and visual deficits in the american lobster (Homarus americanus) from Long Island Sound, NY.

    PubMed

    Magel, Christopher R; Shields, Jeffrey D; Brill, Richard W

    2009-08-01

    In 1999, a mass mortality of the American lobster (Homarus americanus) occurred in western Long Island Sound (WLIS). Although the etiology of this event remains unknown, bottom water temperature, hypoxia, heavy metal poisoning, and pesticides are potential causal factors. Lobsters from WLIS continue to display signs of morbidity, including lethargy and cloudy grey eyes that contain idiopathic lesions. As the effect of these lesions on lobster vision is unknown, we used electroretinography (ERG) to document changes in visual function in lobsters from WLIS, while using histology to quantify the extent of physical damage. Seventy-three percent of lobsters from WLIS showed damage to photoreceptors and optic nerve fibers, including necrosis, cellular breakdown, and hemocyte infiltration in the optic nerves, rhabdoms, and ommatidia. Animals with more than 15% of their photoreceptors exhibiting damage also displayed markedly reduced responses to 10-ms flashes of a broad-spectrum white light. Specifically, maximum voltage (Vmax) responses were significantly lower and occurred at a lower light intensity compared to responses from lobsters lacking idiopathic lesions. Nearly a decade after the 1999 mortality event, lobsters from WLIS still appear to be subjected to a stressor of unknown etiology that causes significant functional damage to the eyes.

  20. Excretory calcinosis: a new fatal disease of wild American lobsters Homarus americanus.

    PubMed

    Dove, Alistair D M; LoBue, Carl; Bowser, Paul; Powell, Mark

    2004-03-10

    A significant number of moribund and dead lobsters Homarus americanus were reported to New York state authorities by lobster fishers in Long Island Sound (LIS) during the summer of 2002. Morbid lobsters were characterised by an orange discolouration of the abdomen, lethargy, an excess of epibionts and poor post-capture survival. On necropsy, severe extensive multifocal or diffuse mineralised granulomatous inflammation of the gills and antennal glands was the most striking pathology. In the gills, granulomas often occluded the lumen of filaments, resulting in congestion, ischemia and coagulative necrosis of gill tissues. In the antennal glands, granulomas were concentrated along the border between the coelomosac and labyrinth. No significant pathogens were recovered from diseased individuals. In prechronic individuals, however, it was evident that granulomas were focused around calcium carbonate (aragonite) crystals. This disease may result from anomalously high sea-bottom temperatures in LIS (approximately 23 degrees C) during the summer of 2002 and associated disruptions of the calcium chemistry of lobsters in favour of deposition of minerals in soft tissues. The ultimate cause of death of affected lobsters is probably respiratory failure due to reduced effective surface area of the gills, exacerbated by hypermetabolic temperatures and an abundance of epibionts.

  1. Histopathology of idiopathic lesions in the eyes of Homarus americanus from Long Island Sound.

    PubMed

    Maniscalco, Andrea M; Shields, Jeffrey D

    2006-02-01

    In 1999, American lobsters, Homarus americanus, from western Long Island Sound (WLIS) experienced a significant mortality. In 2001 and 2004, the eyes and eyestalks of lobsters from WLIS and central LIS were examined for histopathological changes. Idiopathic lesions were identified in the ommatidia and optic nerve fibers proximal to the ommatidia in 29 (56%) of the lobsters from LIS. Lesions were categorized as either moderate or severe. Moderate lesions had altered rhabdoms, clumped pigment, and altered optic nerve fibers. Severe lesions were marked by absent rhabdoms, clumped pigment in both the ommatidial region and in the optic nerve region; and optic nerve fibers that had been completely destroyed and were replaced by vascular tissue. Idiopathic lesions occurred primarily in the central and ventral regions of the eye, and with much less frequency in the dorsal region. In addition, damage to the dorsal area tended to occur only when the severity of lesions was high, indicating a spatially progressive pattern to the lesion development. The lesions occurred in both western and central Long Island Sound, with no significant differences in severity between locations. The prevalence of lesions did not vary between years, but in 2004, several eyes had less severe pathology than those from 2001. These data indicate that the etiological agent is present throughout a large portion of the Sound, and that lobsters are probably continually exposed to it.

  2. Microfibrils provide non-linear elastic behaviour in the abdominal artery of the lobster Homarus americanus.

    PubMed Central

    McConnell, C J; DeMont, M E; Wright, G M

    1997-01-01

    1. Microfibrils are becoming increasingly recognized as an important component of the extra-cellular matrix. However, almost nothing is known about their mechanical role in the diversity of tissues in which they are found. 2. Microfibrils form the principal structural component in the wall of the abdominal artery of the lobster Homarus americanus. We have used previous estimates of the mechanical properties of these microfibrils, estimates of the fraction of the aorta wall volume occupied by the microfibrils, and their angular distribution as a function of strain in a numerical model that predicts the macroscopic mechanical properties of the whole tissue. 3. Microfibrils alone, when their reorientation and deformation are accounted for, characterize the stress-strain behaviour of the vessel. Evidence of the evolutionary conservation of fibrillin between medusans, echinoderms and vertebrates implies that the mechanical properties of lobster microfibrils may apply to microfibrillar function in other taxa. This will have profound implications on the perceived roles of microfibrils in development, physiology and disease. Images Figure 2 Figure 3 Figure 4 PMID:9080378

  3. Dietary lipid requirements of adult lobsters, Homarus americanus (M.E.).

    PubMed

    Castell, J D; Covey, J F

    1976-08-01

    The effects of several dietary lipids on adult American lobster (Homarus americanus) were assessed over a 10 month feeding period. Cod liver oil (CLO) resulted in greater precent weight gains, feed conversion, percent edible meat and higher serum protein and hemocyte counts than either corn oil (CO) or hydrogenated coconut oil (HCO). These differences were probably due to an essential fatty acid (EFA) requirement by the lobster for linolenic series omega3 or other fatty acids present in CLO. The linoleic or omega6 fatty acids of CO appeared to have some sparing effect on several of the EFA deficiency symptoms. It was found that 5% CLO was optimal for mean percent weight gain, molt incidence, feed conversion and hemocyte counts of lobsters. Further increases in dietary CLO to 10% and 15% resulted in no significant improvement of any of the condition indices used. There was a decrease in serum protein and calcium when lobsters were fed a non-saponifiable sterol deficient diet. The addition of 1% cholesterol to the diet raised the serum protein, but resulted in even a greater decrease in the serum calcium level.

  4. Differential expression of American lobster (Homarus americanus) immune related genes during infection of Aerococcus viridans var. homari, the causative agent of Gaffkemia.

    PubMed

    Clark, K Fraser; Acorn, Adam R; Greenwood, Spencer J

    2013-02-01

    This is the first transcriptomic study focusing on immunity in the commercially valuable American lobster (Homarus americanus). We have conducted an in vivo infection trial using the Gram-positive bacterium Aerococcus viridans var. homari to determine how H. americanus responds to this naturally occurring lethal-pathogen. A novel H. americanus microarray was used to measure the transcriptomic changes occurring in over 14,000 genes in the lobster hepatopancreas. Hundreds of new immune genes and isoforms were identified and measured for the first time in this species, and our findings highlight 148 genes of interest involved in H. americanus pathogen response. We verified our microarray results using RT-qPCR on three anti-lipopolysaccharide (ALFHa-1, ALFHa-2, ALFHa-4), a thioredoxin, acute phase serum amyloid protein A, hexokinase and two trypsin genes. RT-qPCR and microarray findings show close agreement and highlight the significant increase in gene expression in many lobster immune genes during A. viridans infection. Differential expression of the ALFHa isoforms may indicate that the H. americanus immune response can be tailored to the class of pathogen causing disease.

  5. Seasonal variability of prey in the stomachs of Astropecten americanus (Echinodermata: Asteroidea) from off southern New England, U.S.A.

    NASA Astrophysics Data System (ADS)

    Franz, David R.; Worley, E. K.

    1982-04-01

    The diet of Astropecten americanus from a location off Nantucket Shoals, Massachusetts, was determined by analysis of stomach contents in May and November. Molluscs, followed by crustaceans, dominated stomach contents. The proportion of molluscan species in the diet differed significantly from the benthos, Juvenile Arctica islandica dominated stomachs in May, but declined sharply in November, probably due in part to predation by Astropecten. Other molluscs, not prevalent in the benthos, were important in stomach contents. Frequency distributions of counts of prey species in a sample of seastar stomachs indicate that some seastars ingest unusually large numbers of certain prey species. A. americanus generally ingests small prey individuals (<4mm) although larger prey are consumed, especially in November. Relatively high selectivity, seasonal shifts in the diversity of stomach contents, and evidence for patch-specific foraging are characteristics of A. americanus which are consistent with general predictions of optimum diet models.

  6. Necator americanus and helminth co-infections: further down-modulation of hookworm-specific type 1 immune responses.

    PubMed

    Geiger, Stefan Michael; Alexander, Neal Douglas Edward; Fujiwara, Ricardo Toshio; Brooker, Simon; Cundill, Bonnie; Diemert, David Joseph; Correa-Oliveira, Rodrigo; Bethony, Jeffrey Michael

    2011-09-01

    Helminth co-infection in humans is common in tropical regions of the world where transmission of soil-transmitted helminths such as Ascaris lumbricoides, Trichuris trichiura, and the hookworms Necator americanus and Ancylostoma duodenale as well as other helminths such as Schistosoma mansoni often occur simultaneously. We investigated whether co-infection with another helminth(s) altered the human immune response to crude antigen extracts from either different stages of N. americanus infection (infective third stage or adult) or different crude antigen extract preparations (adult somatic and adult excretory/secretory). Using these antigens, we compared the cellular and humoral immune responses of individuals mono-infected with hookworm (N. americanus) and individuals co-infected with hookworm and other helminth infections, namely co-infection with either A. lumbricoides, Schistosoma mansoni, or both. Immunological variables were compared between hookworm infection group (mono- versus co-infected) by bootstrap, and principal component analysis (PCA) was used as a data reduction method. Contrary to several animal studies of helminth co-infection, we found that co-infected individuals had a further downmodulated Th1 cytokine response (e.g., reduced INF-γ), accompanied by a significant increase in the hookworm-specific humoral immune response (e.g. higher levels of IgE or IgG4 to crude antigen extracts) compared with mono- infected individuals. Neither of these changes was associated with a reduction of hookworm infection intensity in helminth co-infected individuals. From the standpoint of hookworm vaccine development, these results are relevant; i.e., the specific immune response to hookworm vaccine antigens might be altered by infection with another helminth.

  7. Relationship between body size and habitat complexity preference in age-0 and -1 year winter flounder Pseudopleuronectes americanus.

    PubMed

    Pappal, A L; Rountree, R A; MacDonald, D G

    2012-07-01

    The interaction between body size, habitat complexity and interstice width on habitat preference of age-0 and -1 year Pseudopleuronectes americanus was examined using continuous remote video observation. The habitat choices of juvenile P. americanus were recorded over a 6 h period in tanks with four treatments: bare sand, sand with low complexity cobble, sand with intermediate complexity cobble and sand with high complexity cobble. Both age-0 and -1 year fish preferred cobble to bare sand. Within cobble treatments, age-0 year fish preferred intermediate complexity cobble, with a 1.59 ratio of interstitial space to body width. The largest age-1 year fish (123-130 mm standard length, L(S) ) preferred low complexity cobble. While a significant preference was not detected, medium age-1 year fish (83-88 mm L(S) ) tended to select low complexity cobble, whereas small age-1 year fish (73-82 mm L(S) ) tended to select low and intermediate cobble, with an interstitial space to body width ratio of 1.05. For medium and large age-1 year fish, there was an increased selection of low complexity cobble, corresponding to larger interstitial space to body size ratios. This study indicates that juvenile P. americanus prefer complex habitat to unstructured habitat and that this preference is mediated by a relationship between fish body size and the size of structure interstices. These results contribute to the growing body of knowledge of complex habitat selection and drivers of habitat choice in flatfishes. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

  8. De novo transcriptome assembly for the lobster Homarus americanus and characterization of differential gene expression across nervous system tissues.

    PubMed

    McGrath, Lara Lewis; Vollmer, Steven V; Kaluziak, Stefan T; Ayers, Joseph

    2016-01-16

    The American lobster, Homarus americanus, is an important species as an economically valuable fishery, a key member in marine ecosystems, and a well-studied model for central pattern generation, the neural networks that control rhythmic motor patterns. Despite multi-faceted scientific interest in this species, currently our genetic resources for the lobster are limited. In this study, we de novo assemble a transcriptome for Homarus americanus using central nervous system (CNS), muscle, and hybrid neurosecretory tissues and compare gene expression across these tissue types. In particular, we focus our analysis on genes relevant to central pattern generation and the identity of the neurons in a neural network, which is defined by combinations of genes distinguishing the neuronal behavior and phenotype, including ion channels, neurotransmitters, neuromodulators, receptors, transcription factors, and other gene products. Using samples from the central nervous system (brain, abdominal ganglia), abdominal muscle, and heart (cardiac ganglia, pericardial organs, muscle), we used RNA-Seq to characterize gene expression patterns across tissues types. We also compared control tissues with those challenged with the neuropeptide proctolin in vivo. Our transcriptome generated 34,813 transcripts with known protein annotations. Of these, 5,000-10,000 of annotated transcripts were significantly differentially expressed (DE) across tissue types. We found 421 transcripts for ion channels and identified receptors and/or proteins for over 20 different neurotransmitters and neuromodulators. Results indicated tissue-specific expression of select neuromodulator (allostatin, myomodulin, octopamine, nitric oxide) and neurotransmitter (glutamate, acetylcholine) pathways. We also identify differential expression of ion channel families, including kainite family glutamate receptors, inward-rectifying K(+) (IRK) channels, and transient receptor potential (TRP) A family channels, across central

  9. Fatal Caprine arthritis encephalitis virus-like infection in 4 Rocky Mountain goats (Oreamnos americanus).

    PubMed

    Patton, Kristin M; Bildfell, Robert J; Anderson, Mark L; Cebra, Christopher K; Valentine, Beth A

    2012-03-01

    Over a 3.5-year period, 4 Rocky Mountain goats (Oreamnos americanus), housed at a single facility, developed clinical disease attributed to infection by Caprine arthritis encephalitis virus (CAEV). Ages ranged from 1 to 10 years. Three of the goats, a 1-year-old female, a 2-year-old male, and a 5-year-old male, had been fed raw domestic goat milk from a single source that was later found to have CAEV on the premises. The fourth animal, a 10-year-old male, had not ingested domestic goat milk but had been housed with the other 3 Rocky Mountain goats. All 4 animals had clinical signs of pneumonia prior to death. At necropsy, findings in lungs included marked diffuse interstitial pneumonia characterized histologically by severe lymphoplasmacytic infiltrates with massive alveolar proteinosis, interstitial fibrosis, and type II pneumocyte hyperplasia. One animal also developed left-sided hemiparesis, and locally extensive lymphoplasmacytic myeloencephalitis was present in the cranial cervical spinal cord. Two animals had joint effusions, as well as severe lymphoplasmacytic and ulcerative synovitis. Immunohistochemical staining of fixed sections of lung tissue from all 4 goats, as well as spinal cord in 1 affected animal, and synovium from 2 affected animals were positive for CAEV antigen. Serology testing for anti-CAEV antibodies was positive in the 2 goats tested. The cases suggest that Rocky Mountain goats are susceptible to naturally occurring CAEV infection, that CAEV from domestic goats can be transmitted to this species through infected milk and by horizontal transmission, and that viral infection can result in clinically severe multisystemic disease.

  10. Multilocus heterozygosity, parental relatedness and individual fitness components in a wild mountain goat, Oreamnos americanus population.

    PubMed

    Mainguy, Julien; Côté, Steeve D; Coltman, David W

    2009-05-01

    Matings between relatives lead to a decrease in offspring genetic diversity which can reduce fitness, a phenomenon known as inbreeding depression. Because alpine ungulates generally live in small structured populations and often exhibit a polygynous mating system, they are susceptible to inbreeding. Here, we used marker-based measures of pairwise genetic relatedness and inbreeding to investigate the fitness consequences of matings between relatives in a long-term study population of mountain goats (Oreamnos americanus) at Caw Ridge, Alberta, Canada. We first assessed whether individuals avoided mating with kin by comparing actual and random mating pairs according to their estimated genetic relatedness, which was derived from 25 unlinked polymorphic microsatellite markers and reflected pedigree relatedness. We then examined whether individual multilocus heterozygosity H, used as a measure of inbreeding, was predicted by parental relatedness and associated with yearling survival and the annual probability of giving birth to a kid in adult females. Breeding pairs identified by genetic parentage analyses of offspring that survived to 1 year of age were less genetically related than expected under random matings. Parental relatedness was negatively correlated with offspring H, and more heterozygous yearlings had higher survival to 2 years of age. The probability of giving birth was not affected by H in adult females. Because kids that survived to yearling age were mainly produced by less genetically related parents, our results suggest that some individuals experienced inbreeding depression in early life. Future research will be required to quantify the levels of gene flow between different herds, and evaluate their effects on population genetic diversity and dynamics.

  11. Sequential ovulation and fertility of polyoestrus in American black bears (Ursus americanus).

    PubMed

    Himelright, Brendan M; Moore, Jenna M; Gonzales, Ramona L; Mendoza, Alejandra V; Dye, Penny S; Schuett, Randall J; Durrant, Barbara S; Read, Betsy A; Spady, Thomas J

    2014-01-01

    American black bears (Ursus americanus) are seasonally polyoestrous and exhibit delayed implantation, which may allow equal and independent fertility of recurrent oestruses of a mating season. We postulated that the luteal inactivity during delayed implantation allows bears to have sequential ovulation during a polyoestrous mating season such that each oestrus of a polyoestrous female will have equivalent fertility, and pregnancy would not preclude subsequent ovulation and superfetation. Controlled mating experiments were conducted on semi-free-ranging female American black bears during three mating seasons, wherein females were bred by different male cohorts in each oestrus. Behavioural observation, vulva score ranking, genetic paternity analysis, gross morphology of ovaries and microscopic morphology of diapaused embryos were used to evaluate the fertility of each subsequent oestrus in polyoestrous females. Oestrus duration, number of successful mounts and median vulva scores were similar between first and subsequent oestruses of the season. Polyoestrus occurred in 81.3% of oestrous females, with a 9.7 ± 5.5 day (mean ± SD) inter-oestrous interval. Sequential ovulation was documented in three polyoestrous females, including one that possessed both a corpus haemorrhagicum and a developed corpus luteum. Among polyoestrous dams, four of nine embryos were conceived in the first oestrus and five of nine in the second oestrus. These results indicate that each oestrus of polyoestrous females is capable of fertility, even if the female is already pregnant from a prior oestrus. Although superfetation was not directly observed in the present study, our results strongly suggest the potential of superfetation in the American black bear and provide novel insight into the complex behavioural and physiological breeding mechanisms of bears. Given that most endangered bear species share similar reproductive traits with American black bears, captive breeding programmes

  12. Prevalence of Babesia spp., Ehrlichia spp., and Tick Infestations in Oklahoma Black Bears (Ursus americanus).

    PubMed

    Skinner, Delaina; Mitcham, Jessica R; Starkey, Lindsay A; Noden, Bruce H; Fairbanks, W Sue; Little, Susan E

    2017-06-28

    American black bears (Ursus americanus) are commonly infested with ticks throughout their range, but there are few surveys for tick-borne disease agents in bears. To characterize tick infestations and determine the prevalence of current infection with Babesia spp. and past or current infection with Ehrlichia spp. in newly re-established populations of black bears in east central and southeastern Oklahoma, we identified adult (n=1,048) and immature (n=107) ticks recovered from bears (n=62). We evaluated serum and whole blood samples from a subset (n=49) for antibodies reactive to, and characteristic DNA fragments of Ehrlichia spp. as well as characteristic DNA fragments of Babesia spp. Amblyomma americanum, the most common tick identified, was found on a majority (56/62; 90%) of bears and accounted for 697/1,048 (66.5%) of all ticks recovered. Other ticks included Dermacentor variabilis (338/1,048; 32.3%) from 36 bears, Amblyomma maculatum (9/1,048; 0.9%) from three bears, and Ixodes scapularis (4/1,048; 0.4%) from three bears. Antibodies reactive to Ehrlichia spp. were detected in every bear tested (49/49; 100%); maximum inverse titers to Ehrlichia chaffeensis ranged from 64-4,096 (geometric mean titer 1,525). However, PCR failed to identify active infection with E. chaffeensis, Ehrlichia ewingii, or an Ehrlichia ruminantium-like agent. Infection with Babesia spp. was detected by PCR in 3/49 (6%) bears. Together these data confirm that tick infestations and infection with tick-borne disease agents are common in bears in the southern US. The significance of these infestations and infections to the health of bears, if any, and the identity of the Ehrlichia spp. responsible for the antibody reactivity seen, warrant further evaluation.

  13. Detection of human bacterial pathogens in ticks collected from Louisiana black bears (Ursus americanus luteolus).

    PubMed

    Leydet, Brian F; Liang, Fang-Ting

    2013-04-01

    There are 4 major human-biting tick species in the northeastern United States, which include: Amblyomma americanum, Amblyomma maculatum, Dermacentor variabilis, and Ixodes scapularis. The black bear is a large mammal that has been shown to be parasitized by all the aforementioned ticks. We investigated the bacterial infections in ticks collected from Louisiana black bears (Ursus americanus subspecies luteolus). Eighty-six ticks were collected from 17 black bears in Louisiana from June 2010 to March 2011. All 4 common human-biting tick species were represented. Each tick was subjected to polymerase chain reaction (PCR) targeting select bacterial pathogens and symbionts. Bacterial DNA was detected in 62% of ticks (n=53). Rickettsia parkeri, the causative agent of an emerging spotted fever group rickettsiosis, was identified in 66% of A. maculatum, 28% of D. variabilis, and 11% of I. scapularis. The Lyme disease bacterium, Borrelia burgdorferi, was detected in 2 I. scapularis, while one A. americanum was positive for Borrelia bissettii, a putative human pathogen. The rickettsial endosymbionts Candidatus Rickettsia andeanae, rickettsial endosymbiont of I. scapularis, and Rickettsia amblyommii were detected in their common tick hosts at 21%, 39%, and 60%, respectively. All ticks were PCR-negative for Anaplasma phagocytophilum, Ehrlichia spp., and Babesia microti. This is the first reported detection of R. parkeri in vector ticks in Louisiana; we also report the novel association of R. parkeri with I. scapularis. Detection of both R. parkeri and B. burgdorferi in their respective vectors in Louisiana demands further investigation to determine potential for human exposure to these pathogens. Copyright © 2013 Elsevier GmbH. All rights reserved.

  14. Modulation of gene expression in heart and liver of hibernating black bears (Ursus americanus)

    PubMed Central

    2011-01-01

    Background Hibernation is an adaptive strategy to survive in highly seasonal or unpredictable environments. The molecular and genetic basis of hibernation physiology in mammals has only recently been studied using large scale genomic approaches. We analyzed gene expression in the American black bear, Ursus americanus, using a custom 12,800 cDNA probe microarray to detect differences in expression that occur in heart and liver during winter hibernation in comparison to summer active animals. Results We identified 245 genes in heart and 319 genes in liver that were differentially expressed between winter and summer. The expression of 24 genes was significantly elevated during hibernation in both heart and liver. These genes are mostly involved in lipid catabolism and protein biosynthesis and include RNA binding protein motif 3 (Rbm3), which enhances protein synthesis at mildly hypothermic temperatures. Elevated expression of protein biosynthesis genes suggests induction of translation that may be related to adaptive mechanisms reducing cardiac and muscle atrophies over extended periods of low metabolism and immobility during hibernation in bears. Coordinated reduction of transcription of genes involved in amino acid catabolism suggests redirection of amino acids from catabolic pathways to protein biosynthesis. We identify common for black bears and small mammalian hibernators transcriptional changes in the liver that include induction of genes responsible for fatty acid β oxidation and carbohydrate synthesis and depression of genes involved in lipid biosynthesis, carbohydrate catabolism, cellular respiration and detoxification pathways. Conclusions Our findings show that modulation of gene expression during winter hibernation represents molecular mechanism of adaptation to extreme environments. PMID:21453527

  15. Behavioral Thermoregulation and Trade-Offs in Juvenile Lobster Homarus americanus.

    PubMed

    Nielsen, Travis V; McGaw, Iain J

    2016-02-01

    Water temperature influences the behavior and distribution patterns of both larval and adult American lobster Homarus americanus. However, very little is known about the responses of juvenile lobsters. The juvenile life stage is a critical period; high levels of mortality, combined with specific behavioral responses, can disconnect larval settlement from patterns of abundance of adults. We assessed behavioral thermoregulation in juvenile lobsters, and determined how thermal preferences can be altered by the presence of shelter and food. Juvenile lobsters avoided temperatures higher than 20 °C and lower than 8 °C, and had a mean temperature preference of 16.2 ± 1 °C. This preference was unaffected by prior acclimation, origin (laboratory-raised or wild), or size. When the animals were subjected to a temperature change (5-20 °C), activity rates peaked at 15 °C, and remained stable thereafter. Activity rates did not change when a shelter was added. The addition of food resulted in an increase in activity associated with food handling. When juvenile lobsters were offered a choice between temperature, shelter, and food, they always chose the environment with a shelter, even when it was in a thermally unfavorable temperature. Juveniles also spent more time in a thermally unfavorable environment when food was present; however, acquisition of a shelter was prioritized over food. Although juveniles had a similar thermal preference to adults, they are more vulnerable to predation; the innate shelter-seeking behavior of juveniles overrode their thermal preference. While temperature is an important environmental factor affecting the physiology, distribution, and growth of aquatic ectotherms, our findings suggest that trade-off behaviors occur in order to maintain optimal fitness and survival of the individual. © 2016 Marine Biological Laboratory.

  16. Soil organic matter content effects on dermal pesticide bioconcentration in American toads (Bufo americanus).

    PubMed

    Van Meter, Robin J; Glinski, Donna A; Henderson, W Matthew; Purucker, S Thomas

    2016-11-01

    Pesticides have been implicated as a major factor in global amphibian declines and may pose great risk to terrestrial phase amphibians moving to and from breeding ponds on agricultural landscapes. Dermal uptake from soil is known to occur in amphibians, but predicting pesticide availability and bioconcentration across soil types is not well understood. The present study was designed to compare uptake of 5 current-use pesticides (imidacloprid, atrazine, triadimefon, fipronil, and pendimethalin) in American toads (Bufo americanus) from exposure on soils with significant organic matter content differences (14.1% = high organic matter and 3.1% = low organic matter). We placed toads on high- or low-organic matter soil after applying individual current-use pesticides on the soil surface for an 8-h exposure duration. Whole body tissue homogenates and soils were extracted and analyzed using liquid chromatography-mass spectrometry to determine pesticide tissue and soil concentration, as well as bioconcentration factor in toads. Tissue concentrations were greater on the low-organic matter soil than the high-organic matter soil across all pesticides (average ± standard error; 1.23 ± 0.35 ppm and 0.78 ± 0.23 ppm, respectively), and bioconcentration was significantly higher for toads on the low-organic matter soil (analysis of covariance p = 0.002). Soil organic matter is known to play a significant role in the mobility of pesticides and bioavailability to living organisms. Agricultural soils typically have relatively lower organic matter content and serve as a functional habitat for amphibians. The potential for pesticide accumulation in amphibians moving throughout agricultural landscapes may be greater and should be considered in conservation and policy efforts. Environ Toxicol Chem 2016;35:2734-2741. © 2016 SETAC.

  17. Effects of simulated feeding by snow geese on Scirpus americanus rhizomes.

    PubMed

    Giroux, J -F; Bédard, J

    1987-11-01

    We simulated the feeding of Greater Snow Geese (Chen caerulescens atlantica) on the rhizomes of three-square bulrush (Scirpus americanus) in a tidal marsh along the St. Lawrence River estuary in Québec. During the spring staging period, aboveground biomass is unavailable and geese feed solely on rhizomes and overwintering buds. An experiment was designed to test the effect of three factors on subsequent growth of Scirpus: the intensity of removal (3 to 77% removal of belowground biomass), the number of "bites" (1, 2 or 3 sections removed) and the number of adventitious buds removed (1, 2 or 3). Rhizomes were dug out in May, treated and transplanted into 85-1 basins sunk in the marsh and filled with marsh soil freed of all plant material. Growth was observed weekly until the end of the growing season in August. Shoots and rhizomes were then collected, dried and weighed to obtain biomass estimates. The net above- and belowground production of Scirpus was inversely related to the initial rhizome biomass removed. At a high level of removal (>35%), the cumulative number of shoots was significantly reduced as early as two weeks after transplantation. The relative reduction in production of the treated rhizomes compared to the control plants was also related to the intensity of removal. An increased number of bites reduced production and the removal of an increased number of adventitious buds further amplified the effect of removal on rhizome production. These experimental results show that even low intensity of feeding by Snow Geese can reduce the production of Scirpus marshes.

  18. Sequential ovulation and fertility of polyoestrus in American black bears (Ursus americanus)

    PubMed Central

    Himelright, Brendan M.; Moore, Jenna M.; Gonzales, Ramona L.; Mendoza, Alejandra V.; Dye, Penny S.; Schuett, Randall J.; Durrant, Barbara S.; Read, Betsy A.; Spady, Thomas J.

    2014-01-01

    American black bears (Ursus americanus) are seasonally polyoestrous and exhibit delayed implantation, which may allow equal and independent fertility of recurrent oestruses of a mating season. We postulated that the luteal inactivity during delayed implantation allows bears to have sequential ovulation during a polyoestrous mating season such that each oestrus of a polyoestrous female will have equivalent fertility, and pregnancy would not preclude subsequent ovulation and superfetation. Controlled mating experiments were conducted on semi-free-ranging female American black bears during three mating seasons, wherein females were bred by different male cohorts in each oestrus. Behavioural observation, vulva score ranking, genetic paternity analysis, gross morphology of ovaries and microscopic morphology of diapaused embryos were used to evaluate the fertility of each subsequent oestrus in polyoestrous females. Oestrus duration, number of successful mounts and median vulva scores were similar between first and subsequent oestruses of the season. Polyoestrus occurred in 81.3% of oestrous females, with a 9.7 ± 5.5 day (mean ± SD) inter-oestrous interval. Sequential ovulation was documented in three polyoestrous females, including one that possessed both a corpus haemorrhagicum and a developed corpus luteum. Among polyoestrous dams, four of nine embryos were conceived in the first oestrus and five of nine in the second oestrus. These results indicate that each oestrus of polyoestrous females is capable of fertility, even if the female is already pregnant from a prior oestrus. Although superfetation was not directly observed in the present study, our results strongly suggest the potential of superfetation in the American black bear and provide novel insight into the complex behavioural and physiological breeding mechanisms of bears. Given that most endangered bear species share similar reproductive traits with American black bears, captive breeding programmes

  19. Plasma levels of ursodeoxycholic acid in black bears, Ursus americanus: seasonal changes.

    PubMed

    Solá, Susana; Garshelis, David L; Amaral, Joana D; Noyce, Karen V; Coy, Pam L; Steer, Clifford J; Iaizzo, Paul A; Rodrigues, Cecília M P

    2006-06-01

    To date, no other studies have examined the seasonal changes in circulating levels of various bile acids in the plasma of wild North American black bears, Ursus americanus. Using gas chromatography, bile acid concentrations were measured in plasma samples obtained during either early or late hibernation, and during summer active periods. Thus, specific compositional changes from individual animals were examined through a given year. Total bile acid concentrations in the plasma of these normal animals were found to range between 0.2 and 3.1 micromol/L (0.9 +/- 0.2 micromol/L, mean +/- SEM). Cholic, ursodeoxycholic and chenodeoxycholic acids were the major bile acid species identified. Ursodeoxycholic acid represented 28.0 +/- 2.6% of the total bile acid pool. Deoxycholic and lithocholic acids were found only in small amounts. In addition, total bile acid concentrations were lower in plasma samples obtained during hibernation compared with those obtained during summer active periods (0.6 +/- 0.1 and 1.2 +/- 0.4 micromol/L, respectively; p < 0.05). However, the relative proportion of ursodeoxycholic acid, was significantly greater in winter than in summer (31.5 +/- 3.2% and 22.2 +/- 4.5%, p < 0.05). Finally, taurine-conjugated bile acids were the predominant species in bear plasma, accounting for >67% of the total bile acids. These data demonstrate that ursodeoxycholic acid is a major bile acid in black bear plasma, mostly conjugated with taurine. Further, the finding of seasonal variation in plasma bile acid composition provides evidence to support the possible role that ursodeoxycholic acid may play in cellular protection in hibernating black bears.

  20. Blood lipid concentrations and lipoprotein patterns in captive and wild American black bears (Ursus americanus).

    PubMed

    Frank, Nicholas; Elliott, Sarah B; Allin, Shawn B; Ramsay, Edward C

    2006-02-01

    To compare blood lipid concentrations and lipoprotein patterns for captive and wild American black bears (Ursus americanus). 7 captive and 9 wild adult (> or = 4 years old) black bears. Blood was collected from 2 groups of captive black bears (groups A and B) and 1 group of wild black bears (group C). Blood triglyceride (TG) and cholesterol concentrations were compared among groups. Plasma lipoproteins were isolated by use of a self-generating gradient of iodixanol, and lipoprotein patterns were compared between groups A and B. Captive bears (mean +/- SD, 187.8 +/- 44.4 kg) weighed significantly more than wild bears (mean, 104.8 +/- 41.4 kg), but mean body weight did not differ between groups A and B. Mean blood TG concentrations for groups B (216.8 +/- 16.0 mg/dL) and C (190.7 +/- 34.0 mg/dL) were significantly higher than that of group A (103.9 +/- 25.3 mg/dL). Mean blood cholesterol concentration was also significantly higher for group B (227.8 +/- 8.2 mg/dL) than for groups A (171.7 +/- 35.5 mg/dL) or C (190.8 +/- 26.8 mg/dL). Mean very-low-density lipoprotein TG and low-density lipoprotein cholesterol concentrations were 2- and 3-fold higher, respectively, for group B, compared with concentrations for group A. Blood lipid concentrations vary significantly among populations of black bears. Plasma lipoprotein patterns of captive bears differed significantly between colonies and may have reflected differences in diet or management practices.

  1. Influence of sediment contaminated with untreated pulp and paper mill effluent on winter flounder, Pleuronectes americanus.

    PubMed

    Khan, R A

    2010-01-01

    This study was conducted to ascertain the influence of sediment contaminated with pulp and paper mill effluent in a fjord on winter flounder, Pleuronectes americanus, based on a laboratory study. Flounder, captured from a pristine site, were exposed in a flow-through system for 16 weeks to sediment collected at 2, 5, 7, and 10 km from the outfall. A group of controls was placed in uncontaminated sediment. Mortality occurred almost exclusively in fish exposed to sediment taken from 2 km than from more distant sites. Additionally, the condition factor was lower, the liver was enlarged, and toxicopathic lesions in the liver and spleen were significantly greater in fish submerged in the sediment than in fish from the more distant locations or the controls. Two ectoparasites including a ciliate, Trichodina jadranica, and a monogenean, Gyrodactylus pleuronecti, were observed only in the control group, while a digenean in the digestive tract, Steringophorus furciger, was more abundant in fish exposed to sediment from sites more distant from the outfall and the controls than at 2 km. Comparison of these results with data from a previous gradient field study on biological variables in winter flounder, captured at 2, 5, 7, and 10 km down-current from the outfall, revealed an enlarged liver that was associated with elevated levels of detoxification of hepatic enzymes and prevalence of toxicopathic lesions in both the liver and the spleen; these were significantly greater in samples taken nearest to the outfall from the mill than at more distant sites. Moreover, two metazoan parasites, S. furciger (Digenea) and Echinorhynchus gadi (Acanthocephala), in the digestive were more abundant in samples taken at farther locations and also from the reference sites. These results, based on a laboratory study, are in agreement with previous observations that winter flounder exposed to sediment at the site nearest to the outfall, where high concentrations of toxic contaminants persisted

  2. Spatio-temporal variation in serum chemistry of the lobster, Homarus americanus Milne-Edwards.

    PubMed

    Dove, A D M; Sokolowski, M S; Bartlett, S L; Bowser, P R

    2005-11-01

    Monthly variations in serum chemistry of the American lobster, Homarus americanus Milne-Edwards, were investigated at one location in Long Island Sound (LIS). Comparisons between three locations within and outside LIS were also made for a single time point. Most serum analytes displayed significant fluctuation over the study period and between locations. Temporal patterns could be classified as: low in cool months/high in warm months, i.e. Na, Cl, Na:K ratio, Ca, albumin:globulin ratio, percentage Fe saturation; high in cool months/low in warm months, i.e. pH, K, urea, total protein, albumin, globulin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), lipaemia; June spike, i.e. glucose, cholesterol, creatine kinase, iron, transferrin iron-binding capacity; other less obvious fluctuations, i.e. Mg, PO4; and no apparent fluctuation, i.e. HCO3, alkaline phosphatase. The proportion of samples correctly classified into month of collection by a subset of 13 analytes using discriminant analysis improved as the months progressed from May (0.75) to October (>0.95). Discriminant analysis also resolved 96.5% of samples by location. The significant depression of serum calcium at the eastern LIS site correlates with excretory calcinosis, a calcium storage disease described from lobsters at this site, but contrasts with a seasonal elevation in serum calcium recorded in the temporal component of the study. Serum proteins, the electrolytes Ca and K and the enzymes ALT and AST proved to have the strongest spatio-temporal patterns of variation. Serum chemistry is a useful research tool for lobster populations, but the dearth of information on the homology of analyte functions in this species with those in vertebrate species makes interpretation of the results challenging. Late summer/autumn water conditions appear to cause stress for lobsters in LIS.

  3. Vitellogenin in winter flounder (Pleuronectes americanus) from Long Island Sound and Boston Harbor

    SciTech Connect

    Pereira, J.J.; Ziskowski, J.; Mercaldo-Allen, R.; Kuropat, C.; Leudke, D.; Gould, E. )

    1992-09-01

    Vitellogenin is an egg-yolk precursor protein in teleosts which is crucial to the survival of larvae. Manufactured in the liver, where pollutants are known to accumulate, and transported to the ovary by the blood, its synthesis by the liver or uptake by the gonad can be compromised by accumulation of xenobiotics. In three studies, winter flounder (Pleuronectes americanus) blood samples were taken to determine normal levels of vitellogenin during the reproductive cycle, and to learn how its production might be affected in degraded environments. Specifically, these studies followed the seasonal cycle of vitellogenin production in winter flounder through monthly sampling at relatively clean (Shoreham, New York) and degraded areas (Black Rock and New Haven harbors, Connecticut) in Long Island Sound; examined the relationship between parental vitellogenin levels and survival of offspring by sampling fish that had been spawned at the Milford Laboratory for a reproductive success study; and determined the effect of gross liver lesions on vitellogenin production by sampling flounder from Boston Harbor, Massachusetts, which have been reported to have a high prevalence of liver tumors. Blood vitellogenin levels were determined by measuring alkali-labile phosphate (ALP). Large fish (>30 cm) from the two degraded sites had elevated serum ALP levels relative to those from the clean area. Lowered total ovarian lipid levels in large fish from Black Rock Harbor suggested impaired vitellogenin uptake. There were no significant differences in serum ALP among the small ([le]30 cm) fish from the three sampling sites. Boston Harbor flounder with gross liver lesions had lower ALP values than fish without such lesions. There were no significant differences in ALP values among the spawned fish. 43 refs., 7 figs., 6 tabs.

  4. Multidisciplinary assessment of pollution at three sites in Long Island Sound. [Pseudopleuronectes americanus

    SciTech Connect

    Gronlund, W.D.; Sinlam Chan; McCain, B.B.; Clark, R.C. Jr.; Myers, M.S.; Stein, J.E.; Brown, D.W.; Landahl, J.T.; Krahn, M.M.; Varanasi, U. )

    1991-09-01

    Winter flounder (Pseudopleuronectes americanus) were sampled from three sites located near Norwalk, New Haven, and Niantic, Connecticut, in Long Island Sound during February 1987, to evaluate the degree of chemical contamination and to determine possible effects of contaminant exposure. At each site, sediment ad infaunal invertebrates were also collected and analyzed for trace metals and organic chemicals. Specimens of liver and kidney from winter flounder were examined for histopathological conditions, including the presence of macrophage aggregates in liver tissue. Liver samples were also analyzed for DNA damage (i.e., the formation of adducts between DNA and chemical contaminants). Blood samples were collected and analyzed for erythrocyte micronuclei. The sampling site near New Haven was determined to be the most affected site, from the standpoints of greater chemical contamination and possible effects on winter flounder. Concentrations of aromatic hydrocarbons (AHs) and polychlorinated biphenyls (PCBs) were highest in sediment from this site, and the highest prevalences of the histopathological changes and DNA alterations were also found in the livers of winter flounder from this site. No differences in the concentrations of contaminants in fish or in frequencies of erythrocyte micronuclei in fish blood were found between sites. None of the sites samples had contaminant levels or prevalences of lesions as high as previously found at other East Coast locations (e.g., Boston Harbor, Massachusetts, Raritan Bay, New York). Overall, the results indicate moderate levels of pollution at two of the urban sites in Long Island Sound and provide a framework for expanded studies to better define the extent and impact of chemical pollution in Long Island Sound.

  5. Structural and Functional Characterization of a Multifunctional Alanine-Rich Peptide Analogue from Pleuronectes americanus

    PubMed Central

    Migliolo, Ludovico; Silva, Osmar N.; Silva, Paula A.; Costa, Maysa P.; Costa, Carolina R.; Nolasco, Diego O.; Barbosa, João A. R. G.; Silva, Maria R. R.; Bemquerer, Marcelo P.; Lima, Lidia M. P.; Romanos, Maria T. V.; Freitas, Sonia M.; Magalhães, Beatriz S.; Franco, Octavio L.

    2012-01-01

    Recently, defense peptides that are able to act against several targets have been characterized. The present work focuses on structural and functional evaluation of the peptide analogue Pa-MAP, previously isolated as an antifreeze peptide from Pleuronectes americanus. Pa-MAP showed activities against different targets such as tumoral cells in culture (CACO-2, MCF-7 and HCT-116), bacteria (Escherichia coli ATCC 8739 and Staphylococcus aureus ATCC 25923), viruses (HSV-1 and HSV-2) and fungi (Candida parapsilosis ATCC 22019, Trichophyton mentagrophytes (28d&E) and T. rubrum (327)). This peptide did not show toxicity against mammalian cells such as erythrocytes, Vero and RAW 264.7 cells. Molecular mechanism of action was related to hydrophobic residues, since only the terminal amino group is charged at pH 7 as confirmed by potentiometric titration. In order to shed some light on its structure-function relations, in vitro and in silico assays were carried out using circular dichroism and molecular dynamics. Furthermore, Pa-MAP showed partial unfolding of the peptide changes in a wide pH (3 to 11) and temperature (25 to 95°C) ranges, although it might not reach complete unfolding at 95°C, suggesting a high conformational stability. This peptide also showed a conformational transition with a partial α-helical fold in water and a full α-helical core in SDS and TFE environments. These results were corroborated by spectral data measured at 222 nm and by 50 ns dynamic simulation. In conclusion, data reported here show that Pa-MAP is a potential candidate for drug design against pathogenic microorganisms due to its structural stability and wide activity against a range of targets. PMID:23056574

  6. Differences in female individual reproductive potential among three stocks of winter flounder, Pseudopleuronectes americanus

    NASA Astrophysics Data System (ADS)

    McElroy, W. David; Wuenschel, Mark J.; Press, Yvonna K.; Towle, Emilee K.; McBride, Richard S.

    2013-01-01

    Potential annual fecundity (PAF) and skipped spawning of winter flounder, Pseudopleuronectes americanus, were compared among the three stocks in United States waters and between two spawning seasons. Winter flounder have group-synchronous oocyte development and determinate fecundity. These characteristics enable estimation of PAF just prior to spawning by enumeration of the late-vitellogenic cohort of oocytes, in this case employing the autodiametric method. There was a low level of down-regulation, which was limited to fish in the earlier stages of vitellogenesis. Estimates of PAF increased substantially with female size and age, ranging from < 0.5 million to > 5 million eggs per female. Fecundity at size decreased with increasing latitude. On average, fish from the Southern New England (SNE) stock had the highest individual fecundities at length and Gulf of Maine (GOM) the lowest, but differences varied among the years. Fecundity at length of fish from Georges Bank (GB) was intermediate to these two stocks and displayed less variability at size; however, GB fish grow faster so they had the highest relative fecundity at age. Skipped spawning also exhibited geographic differences; it was infrequent (< 2%) overall, but observed in the two coastal stocks (GOM more than SNE) in both years and was not observed in the GB stock. Fecundity at size between the two years was more similar for SNE fish, but all three stocks were synchronized with higher PAF in 2011 than 2010. Comparisons to previously published estimates suggest fecundity is highly variable in this species. Overall, different rates of reproductive productivity exist among individuals of the three stocks.

  7. Population trends and flight behavior of the American burying beetle, Nicrophorus americanus (Coleoptera: Silphidae), on Block Island, RI

    USGS Publications Warehouse

    Raithel, C.J.; Ginsberg, H.S.; Prospero, M.L.

    2006-01-01

    The endangered American burying beetle, Nicrophorus americanus, was monitored on Block Island, RI, USA, from 1991-2003 using mark-recapture population estimates of adults collected in pitfall traps. Populations increased through time, especially after 1994 when a program was initiated that provided carrion for beetle production. Beetle captures increased with increasing temperature and dew point, and decreased with increasing wind speed. Short distance movement was not related to wind direction, while longer distance flights tended to be downwind. Although many individuals flew considerable distances along transects, most recaptures were in traps near the point of release. These behaviors probably have counterbalancing effects on population estimates.

  8. Species profiles: life histories and environmental requirements of coastal fishes and invertebrates (North Atlantic). American lobster. [Homarus americanus

    SciTech Connect

    MacKenzie, C.; Moring, J.R.

    1985-04-01

    This species profile is a literature summary of the taxonomy, morphology, distribution, life history, and environmental requirements of the American lobster (Homarus americanus). These species profiles are designed to assist in the preparation of environmental impact assessments. The American lobster is a valuable commercial shellfish. After spawning, lobsters undergo a series of molts; as adults they live in coastal and offshore waters. Lobsters are captured in baited traps and incidentally in trawls. About 5 to 6 million pounds were captured commercially in 1983, a downward trend from 1971. Major environmental factors affecting reproduction, growth, and survival are water temperature, oxygen concentration, salinity, and substrate. 82 refs., 2 figs., 3 tabs.

  9. Two species of commercial flatfish, winter flounder, Pleuronectes americanus, and American plaice, Hippoglossoides platessoides, as sentinels of environmental pollution.

    PubMed

    Khan, R A

    2010-08-01

    Two species of marketable-size flatfish, winter flounder (Pleuronectes americanus) and American plaice (Hippoglossoides platessoides) from a fjord, were examined as sentinels for the effects of effluent discharged by a pulp and paper mill in Newfoundland, Canada. Reference samples for comparison were obtained from a pristine fjord. Condition factor, lymphocyte levels and the abundance of two intestinal parasites were significantly greater in flounder and plaice sampled at the reference site while macroscopic and microscopic lesions, and hepatic somatic indices were greater in flatfish taken from the contaminated site. These results suggest that both species of commercial flatfish are useful as sentinels for studying environmental pollution.

  10. Classification of Homarus americanus hemocytes and the use of differential hemocyte counts in lobsters infected with Aerococcus viridans var. homari (Gaffkemia).

    PubMed

    Battison, Andrea; Cawthorn, Richard; Horney, Barbara

    2003-11-01

    Hemocytes of the American lobster (Homarus americanus H. Milne Edwards) were classified after examination of Wright-Giemsa stained cytocentrifuge preparations by brightfield light microscopy. Eleven hemocyte types were identified using morphologic criteria. The classification system was then used to monitor changes in the differential hemocyte count (DHC) of lobsters infected with the Gram positive coccus Aerococcus viridans var. homari, etiologic agent of gaffkemia. The appearance of less mature hemocytes in the DHCs of lobsters in the late stages of infection was similar to the 'left shift' of vertebrate inflammation. Results from this study suggest that DHCs can be used to assess and characterize inflammation in H. americanus and possibly other crustaceans.

  11. Bird-habitat relationships in interior Columbia Basin shrubsteppe

    USGS Publications Warehouse

    Earnst, S.L.; Holmes, A.L.

    2012-01-01

    Vegetation structure is considered an important habitat feature structuring avian communities. In the sagebrush biome, both remotely-sensed and field-acquired measures of big sagebrush (Artemisia tridentata) cover have proven valuable in understanding avian abundance. Differences in structure between the exotic annual cheatgrass (Bromus tectorum) and native bunchgrasses are also expected to be important. We used avian abundance data from 318 point count stations, coupled with field vegetation measurements and a detailed vegetation map, to model abundance for four shrub- and four grassland-associated avian species in southeastern Washington shrubsteppe. Specifically, we ask whether species distinguish between bunchgrass and cheatgrass, and whether mapped, categorical cover types adequately explain species' abundance or whether fine-grained, field-measured differences in vegetation cover are also important. Results indicate that mapped cover types alone can be useful for predicting patterns of distribution and abundance within the sagebrush biome for several avian species (five of eight studied here). However, field-measured sagebrush cover was a strong positive predictor for Sage Sparrow (Amphispiza belli), the only sagebrush obligate in this study, and a strong negative predictor for two grassland associates, Horned Lark (Eremophila alpestris) and Grasshopper Sparrow (Ammodramus savannarum). Likewise, shrub associates did not differ in abundance in sagebrush with a cheatgrass vs. bunchgrass understory, but grassland associates were more common in either bunchgrass (Horned Lark and Grasshopper Sparrow) or cheatgrass grasslands (Long-billed Curlew, Numenius americanus), or tended to use sagebrush-cheatgrass less than sagebrush-bunchgrass (Horned Lark, Grasshopper Sparrow, and Savannah Sparrow, Passerculus sandwichensis).

  12. Nesting ecology of waterbirds at Grays Lake, Idaho

    USGS Publications Warehouse

    Austin, J.E.; Pyle, W.H.

    2004-01-01

    Montane wetlands provide valuable habitat for nesting waterfowl and other waterbirds in the western United States, but relatively little information is available about the nesting ecology of their waterbird communities. We describe the general nesting ecology of breeding waterbirds at a large, shallow montane wetland in southeast Idaho during 1997-2000. Habitats included upland grasslands and intermittently to semipermanently flooded wetland habitats. We located a total of 1207 nests of 23 bird species: eared grebe (Podiceps nigricollis), Canada goose (Branta canadensis), mallard (Anas platyrhynchos), gadwall (A. strepera), American wigeon (A. americana), green-winged teal (A. crecca), blue-winged teal (A. discors), cinnamon teal (A. cyanoptera), northern shoveler (A. clypeata), northern pintail (A. acuta), redhead (Aythya americana), canvasback (A. valisineria), lesser scaup (A. affinis), ruddy duck (Oxyuris jamaicensis), northern harrier (Circus cyaneus), American coot (Fulica americana), Virginia rail (Rallus limicola), greater sandhill crane (Grus canadensis tabida), American avocet (Recurvirostra americana), long-billed curlew (Numenius americanus), Wilsons snipe (Gallinago delicta), Wilsons phalarope (Phalaropus tricolor), and short-eared owl (Asio flammeus). Most nests were initiated in May-early June and were terminated (hatched or destroyed) by the third week of June. Mean daily survival rate (DSR) for Canada goose nests was 0.954 0.005 (SE) (n = 127 nests), equivalent to Mayfield nest success of 21%. Mean DSR for dabbling duck nests over all four years was 0.938 0.006 (n = 141), equivalent to Mayfield nest success of 11%. For all other species where we found >10 nests each year (eared grebe, redhead, canvasback, coot, sandhill crane, American avocet, and Wilsons snipe), >50% of nests found hatched at least one young. Success rates for geese, cranes, and ducks were lower than reported for Grays Lake during 1949-1951 and lower than most other wetlands in

  13. The effects of ambient pH on nitrogen excretion in early life stages of the American toad (Bufo americanus).

    PubMed

    Tattersall, G J; Wright, P A

    1996-04-01

    Acidification of breeding ponds has been identified as a potential threat to the survival and health of North American amphibian populations. The effects of acid exposure on ion and acid-balance are well known, but there is little information on how environmental water pH influences nitrogen balance in amphibians. The aim of this study was to determine the effects of moderately acidic water (pH 6.0) on nitrogen excretion in early life stages of the toad, Bufo americanus. Acid exposure (pH 6.0, 54 h) resulted in a 20-80% increase in ammonia-N excretion rates in embryos and early, middle and late tadpoles stages, whereas there was no significant effect on urea-N excretion. Tissue ammonia concentrations were significantly higher (+33%) in the embryos and 35-65% lower in the three groups of tadpoles exposed to water of pH 6.0 compared to control animals (pH 8.5). In embryos, ammonia excretion accounted for greater than 90% of total nitrogen excretion (ammonia-N + urea-N), but by the late tadpole stage this value had decreased to approximately 65%. These findings indicate that exposure of embryonic and larval B. americanus to moderately acidic water disrupts nitrogen balance by increasing nitrogen loss as ammonia, with no compensatory decrease in urea excretion.

  14. Manganese concentration in lobster (Homarus americanus) gills as an index of exposure to reducing conditions in western Long Island Sound

    USGS Publications Warehouse

    Draxler, Andrew F.J.; Sherrell, Robert M.; Wieczorek, Dan; Lavigne, Michele G.; Paulson, A.J.

    2005-01-01

    We examined the accumulation of manganese (Mn) in gill tissues of chemically nai??ve lobsters held in situ at six sites in Long Island Sound (LIS) for up to six weeks to evaluate the possible contribution of eutrophication-driven habitat quality factors to the 1999 mass mortality of American lobsters (Homarus americanus). These western LIS lobster habitats experience seasonal hypoxia, which results in redox-mobilized Mn being transferred to and deposited on the tissues of the lobsters. Manganese accumulated in gill tissue of lobsters throughout the study, but rates were highest at western and southern LIS sites, ranging from 3.4-0.8 ??g/g/d (???16 ??g/g initial). The Baden-Eriksson observation that Mn accumulation in Norway lobsters (Nephrops norvegicus) is associated with ecosystem hypoxia is confirmed and extended to H. americanus. It seems likely that, after accounting for molting frequency, certain critical values may be applied to other lobster habitats of the NE US shelf. If a high proportion of lobsters in autumn have gill Mn concentrations exceeding 30 ??g/g, then the habitats are likely experiencing some reduced oxygen levels. Manganese concentrations above 100 ??g/g suggest exposure to conditions with the potential for lobster mortality should the temperatures of bottom waters become elevated, and gill concentrations above some higher level (perhaps 300 ??g/g) indicate the most severe habitat conditions with a strong potential for hypoxia stress.

  15. Molecular Detection of Ancylostoma duodenale, Ancylostoma ceylanicum, and Necator americanus in Humans in Northeastern and Southern Thailand

    PubMed Central

    Phosuk, Issarapong; Thanchomnang, Tongjit; Sanpool, Oranuch; Janwan, Penchom; Laummaunwai, Porntip; Aamnart, Witthaya; Morakote, Nimit; Maleewong, Wanchai

    2013-01-01

    The 2 principal species of hookworms infecting humans are Necator americanus and Ancylostoma duodenale. Case studies on zoonotic hookworm infections with Ancylostoma ceylanicum and/or Ancylostoma caninum are known mainly from Asian countries. Of these 2 zoonotic species, only A. ceylanicum can develop to adulthood in humans. In the present study, we report a molecular-based survey of human hookworm infections present in southern and northeastern Thailand. Thirty larval hookworm samples were obtained from fecal agar plate cultures of 10 patients in northeastren Thailand and 20 in southern Thailand. Partial ITS1, 5.8S, and ITS2 regions of the ribosomal DNA genes were amplified using PCR. The amplicons were sequenced, aligned, and compared with other hookworm sequences in GenBank database. The results showed that, in Thailand, N. americanus is more prevalent than Ancylostoma spp. and is found in both study areas. Sporadic cases of A. ceylanicum and A. duodenale infection were seen in northeastern Thailand. PMID:24516284

  16. Forces generated during stretch in the heart of the lobster Homarus americanus are anisotropic and are altered by neuromodulators

    PubMed Central

    Dickinson, E. S.; Johnson, A. S.; Ellers, O.; Dickinson, P. S.

    2016-01-01

    ABSTRACT Mechanical and neurophysiological anisotropies mediate three-dimensional responses of the heart of Homarus americanus. Although hearts in vivo are loaded multi-axially by pressure, studies of invertebrate cardiac function typically use uniaxial tests. To generate whole-heart length–tension curves, stretch pyramids at constant lengthening and shortening rates were imposed uniaxially and biaxially along longitudinal and transverse axes of the beating whole heart. To determine whether neuropeptides that are known to modulate cardiac activity in H. americanus affect the active or passive components of these length–tension curves, we also performed these tests in the presence of SGRNFLRFamide (SGRN) and GYSNRNYLRFamide (GYS). In uniaxial and biaxial tests, both passive and active forces increased with stretch along both measurement axes. The increase in passive forces was anisotropic, with greater increases along the longitudinal axis. Passive forces showed hysteresis and active forces were higher during lengthening than shortening phases of the stretch pyramid. Active forces at a given length were increased by both neuropeptides. To exert these effects, neuropeptides might have acted indirectly on the muscle via their effects on the cardiac ganglion, directly on the neuromuscular junction, or directly on the muscles. Because increases in response to stretch were also seen in stimulated motor nerve-muscle preparations, at least some of the effects of the peptides are likely peripheral. Taken together, these findings suggest that flexibility in rhythmic cardiac contractions results from the amplified effects of neuropeptides interacting with the length–tension characteristics of the heart. PMID:26896540

  17. Mass Spectral Analysis of Neuropeptide Expression and Distribution in the Nervous System of the Lobster Homarus americanus

    PubMed Central

    Chen, Ruibing; Jiang, Xiaoyue; Prieto Conaway, Maria C.; Mohtashemi, Iman; Hui, Limei; Viner, Rosa; Li, Lingjun

    2010-01-01

    The lobster Homarus americanus has long served as an important animal model for electrophysiological and behavioral studies. Using this model, we performed a comprehensive investigation of the neuropeptide expression and their localization in the nervous system, which provides useful insights for further understanding of their biological functions. Using nanoLC ESI Q-TOF MS/MS and three types of MALDI instruments, we analyzed the neuropeptide complements in a major neuroendocrine structure, pericardial organ. 57 putative neuropeptides were identified and 18 of them were de novo sequenced. Using direct tissue/extract analysis and bioinformatics software SpecPlot, we charted the global distribution of neuropeptides throughout the nervous system in H. americanus. Furthermore, we also mapped the localization of several neuropeptide families in the brain by high mass resolution and high mass accuracy mass spectrometric imaging (MSI) using a MALDI LTQ Orbitrap mass spectrometer. We have also compared the utility and instrument performance of multiple mass spectrometers for neuropeptide analysis in terms of peptidome coverage, sensitivity, mass spectral resolution and capability for de novo sequencing. PMID:20025296

  18. Dental and Temporomandibular Joint Pathology of the American Black Bear (Ursus americanus).

    PubMed

    Clark, E J; Chesnutt, S R; Winer, J N; Kass, P H; Verstraete, F J M

    Museum specimens (maxillae and/or mandibles) from 371 American black bears (Ursus americanus) acquired between 1889 and 2006 were examined macroscopically according to predefined criteria, and 348 were included in this study. Of the 348 specimens, 126 (36.2%) were from male animals, 106 (30.5%) were from female animals and 116 (33.3%) were from animals of unknown sex. Specimen ages ranged from young adult (n = 63, 18.1%) to adult (n = 285, 81.9%), with juveniles excluded from the study. The number of teeth available for examination was 12,019 (82.2%); 7.0% of teeth were absent artefactually, 0.4% were deemed absent due to acquired tooth loss and 9.7% were absent congenitally. In 43 specimens (12.3%), 82 teeth (0.68%) were small vestigial structures with crowns that were flush with the level of surrounding alveolar bone. The remaining teeth (99.3%) were of normal morphology. Only three supernumerary teeth and three instances of enamel hypoplasia were encountered. Persistent deciduous teeth or teeth with an aberrant number of roots were not encountered in any of the specimens. Approximately one-third of the teeth examined (4,543, 37.8%) displayed attrition/abrasion, affecting nearly all of the specimens (n = 338, 97.1%). Incisor and molar teeth accounted for 52.5% and 34.3% of the affected teeth, respectively, with significantly more adults affected than young adults. Dental fractures were noted in 63 bears, affecting 18.1% of specimens and 1.0% of the total number of present teeth. The canine teeth were most often fractured, with adults having significantly more complicated crown fractures of these teeth than young adults. There were 11 specimens (3.2%) that displayed periapical lesions, affecting 12 (0.1%) dental alveoli. There were 179 specimens (51.4%) displaying bony changes indicative of periodontitis, affecting 816 (6.8%) dental alveoli. The proportion of adult bears affected by periodontitis (57.9%) was significantly greater than that of young adults

  19. Candidatus Liberibacter americanus induces significant reprogramming of the transcriptome of the susceptible citrus genotype

    PubMed Central

    2013-01-01

    Background Citrus huanglongbing (HLB) disease is caused by endogenous, phloem-restricted, Gram negative, uncultured bacteria named Candidatus Liberibacter africanus (CaLaf), Ca. L. asiaticus (CaLas), and Ca. L. americanus (CaLam), depending on the continent where the bacteria were first detected. The Asian citrus psyllid vector, Diaphorina citri, transmits CaLas and CaLam and both Liberibacter species are present in Brazil. Several studies of the transcriptional response of citrus plants manifesting HLB symptoms have been reported, but only for CaLas infection. This study evaluated the transcriptional reprogramming of a susceptible genotype of sweet orange challenged with CaLam, using a customized 385K microarray containing approximately 32,000 unigene transcripts. We analyzed global changes in gene expression of CaLam-infected leaves of sweet orange during the symptomatic stage of infection and compared the results with previously published microarray studies that used CaLas-infected plants. Twenty candidate genes were selected to validate the expression profiles in symptomatic and asymptomatic PCR-positive leaves infected with CaLas or CaLam. Results The microarray analysis identified 633 differentially expressed genes during the symptomatic stage of CaLam infection. Among them, 418 (66%) were upregulated and 215 (34%) were down regulated. Five hundred and fourteen genes (81%) were orthologs of genes from Arabidopsis thaliana. Gene set enrichment analysis (GSEA) revealed that several of the transcripts encoded transporters associated with the endomembrane system, especially zinc transport. Among the most biologically relevant gene transcripts in GSEA were those related to signaling, metabolism and/or stimulus to hormones, genes responding to stress and pathogenesis, biosynthesis of secondary metabolites, oxidative stress and transcription factors belonging to different families. Real time PCR of 20 candidate genes validated the expression pattern of some genes in

  20. Comparison of Two Bacterial Transport Media for Culture of Tonsilar Swabs from Bighorn Sheep ( Ovis canadensis ) and Mountain Goats ( Oreamnos americanus ).

    PubMed

    Roug, Annette; Diaz-Campos, Dubraska; Teitzel, Charlene; Besser, Thomas E

    2017-01-01

    Duplicate tonsilar swabs were collected from 77 bighorn sheep ( Ovis canadensis ) and 19 mountain goats ( Oreamnos americanus ) in Utah. Swabs were refrigerated in bacterial transport medium or frozen in cryopreservation medium prior to bacteriologic culture. The cryopreservation medium yielded comparable or superior bacterial growth while permitting more flexibility in specimen shipment to the laboratory.

  1. Use of acepromazine and medetomidine in combination for sedation and handling of Rocky Mountain elk (Cervus elaphus nelsoni) and black bears (Ursus americanus).

    PubMed

    Wolfe, Lisa L; Johnson, Heather E; Fisher, Mark C; Sirochman, Michael A; Kraft, Benjamin; Miller, Michael W

    2014-10-01

    We opportunistically evaluated a combination of acepromazine maleate and medetomidine HCl for use in sedating Rocky Mountain elk (Cervus elaphus nelsoni) and black bears (Ursus americanus) as an alternative to scheduled drug combinations. This combination was safe and effective with limitations inherent in its sedative rather than anesthetic properties.

  2. ISOLATION AND GENETIC CHARACTERIZATION OF TOXOPLASMA GONDII FROM RACCOONS (PROCYON LOTOR), CATS (FELIS DOMESTICUS), STRIPED SKUNK (MEPHITIS MEPHITIS), BLACK BEAR (URSUS AMERICANUS), AND COUGAR (PUMA CONCOLOR) FROM CANADA

    USDA-ARS?s Scientific Manuscript database

    Viable Toxoplasma gondii was isolated by bioassay in mice from tissues of 2 feral cats ( Felis domesticus), 2 raccoons (Procyon lotor), a skunk (Mephitis mephitis) trapped in remote locations in Manitoba, Canada, and a black bear (Ursus americanus ) from Kuujjuaq, northern Quebec, Canada. Geno...

  3. The introduced clam Ensis americanus in the Wadden Sea: field experiment on impact of bird predation and tidal level on survival and growth

    NASA Astrophysics Data System (ADS)

    Freudendahl, Anna Sofie L.; Nielsen, Mette M.; Jensen, Tomas; Jensen, Kurt Thomas

    2010-06-01

    In the Danish Wadden Sea the intertidal distribution of the introduced bivalve Ensis americanus (syn. E. directus) is restricted to a narrow zone around the mean low water level. To test the possible impact of birds and submersion time on dynamics and distribution of the clams, adult specimens of E. americanus collected near the low water line were transplanted to two intertidal sites and established in open and net-covered experimental plots for 9 weeks (autumn 2001). The lowest survival of clams was registered at the low-shore-site (LSS) in plots open to bird predators, suggesting that birds such as Common Eider ( Somateria mollissima) or Oystercatcher ( Haematopus ostralegus) may control the abundance of E. americanus at the lower tidal levels. For clams showing increment in shell length during the study period, the shell growth rates were highest at the LSS and lowest in the open plots at the high-shore-site (HSS). Differences in immersion time and thus food supply may explain this pattern. Body mass index (BMI) of the clams showed basically the same pattern as the survivorship: lowest BMI in open plots at the LSS and highest in the covered plots at this site. Clams from the HSS were intermediate in their BMI. Disturbance by birds in the open plots at the LSS may explain the low BMI. In conclusion birds may be an important factor controlling abundance of E. americanus in the lower intertidal zone.

  4. An environmental assessment and risk map of Ascaris lumbricoides and Necator americanus distributions in Manufahi District, Timor-Leste.

    PubMed

    Wardell, Rebecca; Clements, Archie C A; Lal, Aparna; Summers, David; Llewellyn, Stacey; Campbell, Suzy J; McCarthy, James; Gray, Darren J; V Nery, Susana

    2017-05-01

    In Timor-Leste there have been intermittent and ineffective soil-transmitted helminth (STH) deworming programs since 2004. In a resource-constrained setting, having information on the geographic distribution of STH can aid in prioritising high risk communities for intervention. This study aimed to quantify the environmental risk factors for STH infection and to produce a risk map of STH in Manufahi district, Timor-Leste. Georeferenced cross-sectional data and stool samples were obtained from 2,194 participants in 606 households in 24 villages in the Manufahi District as part of cross sectional surveys done in the context of the "WASH for Worms" randomised controlled trial. Infection status was determined for Ascaris lumbricoides and Necator americanus using real-time quantitative polymerase chain reaction. Baseline infection data were linked to environmental data obtained for each household. Univariable and multivariable multilevel mixed-effects logistic regression analysis with random effects at the village and household level were conducted, with all models adjusted for age and sex. For A. lumbricoides, being a school-aged child increased the odds of infection, whilst higher temperatures in the coolest quarter of the year, alkaline soils, clay loam/loam soils and woody savannas around households were associated with decreased infection odds. For N. americanus, greater precipitation in the driest month, higher average enhanced vegetation index, age and sandy loam soils increased infection odds, whereas being female and living at higher elevations decreased the odds of infection. Predictive risk maps generated for Manufahi based upon these final models highlight the high predicted risk of N. americanus infection across the district and the more focal nature of A. lumbricoides infection. The predicted risk of any STH infection is high across the entire district. The widespread predicted risk of any STH infection in 6 to 18 year olds provides strong evidence to

  5. Persistent Bovine Viral Diarrhea Virus Infection in Domestic and Wild Small Ruminants and Camelids Including the Mountain Goat (Oreamnos americanus).

    PubMed

    Nelson, Danielle D; Duprau, Jennifer L; Wolff, Peregrine L; Evermann, James F

    2015-01-01

    Bovine viral diarrhea virus (BVDV) is a pestivirus best known for causing a variety of disease syndromes in cattle, including gastrointestinal disease, reproductive insufficiency, immunosuppression, mucosal disease, and hemorrhagic syndrome. The virus can be spread by transiently infected individuals and by persistently infected animals that may be asymptomatic while shedding large amounts of virus throughout their lifetime. BVDV has been reported in over 40 domestic and free-ranging species, and persistent infection has been described in eight of those species: white-tailed deer, mule deer, eland, mousedeer, mountain goats, alpacas, sheep, and domestic swine. This paper reviews the various aspects of BVDV transmission, disease syndromes, diagnosis, control, and prevention, as well as examines BVDV infection in domestic and wild small ruminants and camelids including mountain goats (Oreamnos americanus).

  6. Persistent Bovine Viral Diarrhea Virus Infection in Domestic and Wild Small Ruminants and Camelids Including the Mountain Goat (Oreamnos americanus)

    PubMed Central

    Nelson, Danielle D.; Duprau, Jennifer L.; Wolff, Peregrine L.; Evermann, James F.

    2016-01-01

    Bovine viral diarrhea virus (BVDV) is a pestivirus best known for causing a variety of disease syndromes in cattle, including gastrointestinal disease, reproductive insufficiency, immunosuppression, mucosal disease, and hemorrhagic syndrome. The virus can be spread by transiently infected individuals and by persistently infected animals that may be asymptomatic while shedding large amounts of virus throughout their lifetime. BVDV has been reported in over 40 domestic and free-ranging species, and persistent infection has been described in eight of those species: white-tailed deer, mule deer, eland, mousedeer, mountain goats, alpacas, sheep, and domestic swine. This paper reviews the various aspects of BVDV transmission, disease syndromes, diagnosis, control, and prevention, as well as examines BVDV infection in domestic and wild small ruminants and camelids including mountain goats (Oreamnos americanus). PMID:26779126

  7. Negative density-dependent dispersal in the American black bear (Ursus americanus) revealed by noninvasive sampling and genotyping

    PubMed Central

    Roy, Justin; Yannic, Glenn; Côté, Steeve D; Bernatchez, Louis

    2012-01-01

    Although the dispersal of animals is influenced by a variety of factors, few studies have used a condition-dependent approach to assess it. The mechanisms underlying dispersal are thus poorly known in many species, especially in large mammals. We used 10 microsatellite loci to examine population density effects on sex-specific dispersal behavior in the American black bear, Ursus americanus. We tested whether dispersal increases with population density in both sexes. Fine-scale genetic structure was investigated in each of four sampling areas using Mantel tests and spatial autocorrelation analyses. Our results revealed male-biased dispersal pattern in low-density areas. As population density increased, females appeared to exhibit philopatry at smaller scales. Fine-scale genetic structure for males at higher densities may indicate reduced dispersal distances and delayed dispersal by subadults. PMID:22822432

  8. Serologic survey of Toxoplasma gondii in grizzly bears (Ursus arctos) and black bears (Ursus americanus), from Alaska, 1988 to 1991.

    PubMed

    Chomel, B B; Zarnke, R L; Kasten, R W; Kass, P H; Mendes, E

    1995-10-01

    We tested 644 serum samples from 480 grizzly bears and 40 black bears from Alaska (USA), collected between 1988 and 1991, for Toxoplasma gondii antibodies, using a commercially available latex agglutination test (LAT). A titer > or = 64 was considered positive. Serum antibody prevalence for T. gondii in grizzly bears (Ursus arctos) was 18% (87 of 480). Prevalence ranged from 9% (seven of 77) on Kodiak Island to 28% (15 of 54) in northern Alaska. Prevalence was directly correlated to age. No grizzly bears < 2-year-old had T. gondii antibody. High antibody titers were found mainly in grizzly bears captured north of the Arctic Circle. Antibody prevalence in black bears (Ursus americanus) from Interior Alaska was 15% (six of 40), similar to the prevalence in grizzly bears from the same area (13%; five of 40).

  9. Investigation of American lobster, Homarus americanus, for the presence of chlorinated dibenzo-rho-dioxins and dibenzofurans

    SciTech Connect

    Clement, R.E.; Tosine, H.M.; Taguchi, V.; Musial, C.J.; Uthe, J.F.

    1987-12-01

    The polychlorinated dibenzo-p-dioxins (PCDD) are a group of 75 compounds of current environmental concern. Most attention has been focused on the 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8,-TCDD) because of high toxicity exhibited in laboratory animal studies. Polychlorinated dibenzofurans (PCDF) comprise 135 compounds similar to the PCDD in structure and toxicity. The 2,3,7,8-tetrachlorodibenzofuran (2,3,7,8-TCDF) is the most toxic of this group. Two principal sources of PCDD and PCDF in the environment are incineration and as by-products in the manufacture and use of pentachlorophenols. American lobsters (Homarus americanus) have not been previously investigated for the presence of PCDD and PCDF. Lobsters were examined in this study because of their proximity to possible sources of PCDD and PCDF and an ability to concentrate hydrophobic organics such as polycyclic aromatic hydrocarbons (PAH) in the digestive gland.

  10. Cadmium contamination in American lobster, Homarus americanus, near a coastal lead smelter: use of multiple linear regression for management

    SciTech Connect

    Uthe, J.F.; Scott, D.P.; Chou, C.L.

    1987-04-01

    In 1980 cadmium (Cd) concentrations in digestive gland from American Lobster (Homarus americanus), captured at Belledune Harbour, New Brunswick, Canada were found to range 47.6-372 mg/kg wet weight. Since the digestive gland is commonly eaten the harbor fishery was closed. The adjacent area was decreed a controlled fishery zone. The cadmium source was a lead smelter on the harbor shore. The company installed an aqueous effluent treatment plant and improved handling procedures within the plant area. Aqueous Cd discharges were subsequently reduced by more than 95%. Cadmium levels in lobsters have been monitored annually since 1980 by sampling in early spring, immediately after the lobsters emerged from their overwintering locations. The results from the 1981-1985 monitoring program were used to model the system, analyze the data and predict the years in which certain changes to the management plan might be implemented.

  11. Serologic Survey of Snowshoe Hares (Lepus americanus) in the Greater Yellowstone Area for Brucellosis, Tularemia, and Snowshoe Hare Virus.

    PubMed

    Tyers, Dan; Zimmer, Jeremy; Lewandowski, Kristen; Hennager, Steve; Young, John; Pappert, Ryan; Panella, Amanda; Kosoy, Olga

    2015-07-01

    We examined sera from snowshoe hares (Lepus americanus) livetrapped in the northern Greater Yellowstone Area (GYA), US, for antibodies to Brucella abortus, Francisella tularensis, and snowshoe hare virus (SSHV). Zero of 90, 0 of 67, and 40 of 100 samples were antibody positive for B. abortus, F. tularensis, and SSHV, respectively. Hares were trapped from 2009 to 2012, and of the six animals that were captured twice with at least 1 yr between captures, four developed antibody to SSHV, indicating active exposure to the agent. These findings suggest snowshoe hares in the GYA do not play a significant role as a reservoir of B. abortus, but do maintain the zoonotic, encephalitic SSHV in the population.

  12. Effects of Multiple Routes of Cadmium Exposure on the Hibernation Success of the American Toad (Bufo americanus)

    USGS Publications Warehouse

    James, S.M.; Little, E.E.; Semlitsch, R.D.

    2004-01-01

    The effects of multiple routes of cadmium exposure on juvenile American toads (Bufo americanus) were evaluated using environmentally relevant concentrations. During or after exposure, toads were individually hibernated for 172 days at approximately 4??C. The following experiments were conducted: (1) dermal exposure (hibernation in soil contaminated with up to 120 ??g Cd/ g (dry weight)); (2) injection exposure (single injection with cadmium to achieve a maximum whole-body nominal concentration of 3 ??g Cd/g (wet weight) 12 days before hibernation in uncontaminated soil); and, (3) oral exposure (feeding with mealworms containing ???16 ??g Cd/g (dry weight) for 50 days before hibernation in uncontaminated soil)., We hypothesized that sublethal levels of cadmium would become lethal during hibernation because of combined chemical and cold stress. No prehibernation mortality occurred in the injection and oral exposure studies. There was a significant treatment effect on whole-body cadmium concentration in toads orally or dermally exposed and on percent of cadmium retention in toads orally exposed. There was also a trend of increased time-to-burrowing and more toads partially buried with greater cadmium concentration in the dermal study, which indicated avoidance. In all 3 experiments, no significant differences were found among cadmium treatments in hibernation survival, percent of mass loss, or locomotor performance. However, toads fed mealworms averaging 4.7 ??g Cd/g (dry weight) had only 56% survival compared with 100% survival for controls. Although our results suggest that environmentally relevant levels of cadmium do not pose a great risk to American toads, factors such as soil type or prey species may increase cadmium bioavailability, and other amphibian species may be more sensitive to cadmium than B. americanus.

  13. Phylogeographic Analyses of American Black Bears (Ursus americanus) Suggest Four Glacial Refugia and Complex Patterns of Postglacial Admixture.

    PubMed

    Puckett, Emily E; Etter, Paul D; Johnson, Eric A; Eggert, Lori S

    2015-09-01

    Studies of species with continental distributions continue to identify intraspecific lineages despite continuous habitat. Lineages may form due to isolation by distance, adaptation, divergence across barriers, or genetic drift following range expansion. We investigated lineage diversification and admixture within American black bears (Ursus americanus) across their range using 22 k single nucleotide polymorphisms and mitochondrial DNA sequences. We identified three subcontinental nuclear clusters which we further divided into nine geographic regions: Alaskan (Alaska-East), eastern (Central Interior Highlands, Great Lakes, Northeast, Southeast), and western (Alaska-West, West, Pacific Coast, Southwest). We estimated that the western cluster diverged 67 ka, before eastern and Alaskan divergence 31 ka; these divergence dates contrasted with those from the mitochondrial genome where clades A and B diverged 1.07 Ma, and clades A-east and A-west diverged 169 ka. We combined estimates of divergence timing with hindcast species distribution models to infer glacial refugia for the species in Beringia, Pacific Northwest, Southwest, and Southeast. Our results show a complex arrangement of admixture due to expansion out of multiple refugia. The delineation of the genomic population clusters was inconsistent with the ranges for 16 previously described subspecies. Ranges for U. a. pugnax and U. a. cinnamomum were concordant with admixed clusters, calling into question how to order taxa below the species level. Additionally, our finding that U. a. floridanus has not diverged from U. a. americanus also suggests that morphology and genetics should be reanalyzed to assess taxonomic designations relevant to the conservation management of the species. © The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved.For permissions please email: journals.permissions@oup.com.

  14. Biomarker analysis of American toad (Anaxyrus americanus) and grey tree frog (Hyla versicolor) tadpoles following exposure to atrazine.

    PubMed

    Snyder, Marcía N; Henderson, W Matthew; Glinski, Donna A; Purucker, S Thomas

    2017-01-01

    The objective of the current study was to use a biomarker-based approach to investigate the influence of atrazine exposure on American toad (Anaxyrus americanus) and grey tree frog (Hyla versicolor) tadpoles. Atrazine is one of the most frequently detected herbicides in environmental matrices throughout the United States. In surface waters, it has been found at concentrations from 0.04-2859μg/L and thus presents a likely exposure scenario for non-target species such as amphibians. Studies have examined the effect of atrazine on the metamorphic parameters of amphibians, however, the data are often contradictory. Gosner stage 22-24 tadpoles were exposed to 0 (control), 10, 50, 250 or 1250μg/L of atrazine for 48h. Endogenous polar metabolites were extracted and analyzed using gas chromatography coupled with mass spectrometry. Statistical analyses of the acquired spectra with machine learning classification models demonstrated identifiable changes in the metabolomic profiles between exposed and control tadpoles. Support vector machine models with recursive feature elimination created a more efficient, non-parametric data analysis and increased interpretability of metabolomic profiles. Biochemical fluxes observed in the exposed groups of both A. americanus and H. versicolor displayed perturbations in a number of classes of biological macromolecules including fatty acids, amino acids, purine nucleosides, pyrimidines, and mono- and di-saccharides. Metabolomic pathway analyses are consistent with findings of other studies demonstrating disruption of amino acid and energy metabolism from atrazine exposure to non-target species. Copyright © 2016. Published by Elsevier B.V.

  15. Application of random amplified polymorphic DNA (RAPD) analysis for identification of grouper (Epinephelus guaza), wreck fish (Polyprion americanus), and Nile perch (Lates niloticus) fillets.

    PubMed

    Asensio, Luis; González, Isabel; Fernández, Alicia; Rodríguez, Miguel A; Lobo, Esther; Hernández, Pablo E; García, Teresa; Martín, Rosario

    2002-02-01

    A random amplified polymorphic DNA (RAPD) method was developed for the specific identification of grouper (Epinephelus guaza), wreck fish (Polyprion americanus), and Nile perch (Lates niloticus) fillets. Using two different reaction primers (S1 and L1), RAPD analysis produced clear fingerprints from which the three fish species could be easily identified. This approach is rapid and reliable and offers the potential to detect fraudulent or unintentional mislabeling of these species in routine seafood authentication analysis.

  16. Lead, chromium and manganese removal by in vitro root cultures of two aquatic macrophytes species: Typha latifolia L. and Scirpus americanus pers.

    PubMed

    Santos-Díaz, María del Socorro; Barrón-Cruz, María del Carmen

    2011-07-01

    The ability of in vitro roots cultures of Typha latifolia and Scirpus americanus to remove metals was studied. Roots were cultivated on Murashige-Skoog medium with 15 microg L(-1) Cr 11, 60 microg L(-1) Pb II or 1.8 mg L(-1) Mn II. Adsorbed metal to root surface was removed by washing with 0.042% HNO3. T. latifolia roots were able to uptake 68.8 microg Pb g(-1), 22.1 microg Cr g(-1) and 1680 microg Mn g(-1), while the S. americanus roots removed 148.3 microg Pb g(-1), 40.7 microg Cr g(-1) and 4037 microg Mn g(-1). About 80-90% of Pb and Cr were absorbed in both cultures. On the contrary, the Mn removal was due mainly to an adsorption process (82-86%). In comparison to the T. latifolia cultures, S. americanus cultures were twofold more efficient to remove Pb and Cr, and threefold more efficient to remove Mn. Both plant species capture metals in the following order: Cr >Pb >Mn. This investigation confirms that in vitro roots cultures could be an alternative as a phytoremediation approach for contaminated water with heavy metals.

  17. Seasonal patterns of winter flounder Pseudopleuronectes americanus abundance and reproductive condition on the New York Bight continental shelf.

    PubMed

    Wuenschel, M J; Able, K W; Byrne, D

    2009-05-01

    To resolve varied and sometimes conflicting accounts of spawning and habitat characteristics for winter flounder Pseudopleuronectes americanus, seasonal patterns in abundance and reproductive condition were investigated in the New York Bight, near the southern edge of their current reproductive range. Fish were collected from trawl surveys on the inner continental shelf from October 2006 to October 2007. Pseudopleuronectes americanus were most abundant during January and April surveys, were rarely collected in August, with intermediate abundances in June and October. Measurements of fish condition [hepato-somatic index (I(H)), condition factor (K) and the per cent dry mass of muscle tissue (%M(D))] and reproductive condition [gonado-somatic index (I(G))] were determined to evaluate seasonal changes in energy accumulation and depletion and reproduction. Males and females had similar patterns in body and reproductive condition, although the magnitude of change was greater for females. I(H) values were highest during spring and early summer, suggesting increased feeding following spawning. K and %M(D) increased through spring and summer then declined in the autumn and winter concurrent with gonadal development. Gonads began developing in the autumn, and in January, I(G) values approached spawning levels, with many spent individuals collected in spring. Within these general patterns, however, there was a large degree of variability among individuals, and a few mature non-reproductive ('skipped spawning') females were observed. In the period after spawning, increased energy intake, indicated by increased I(H), may influence reproductive output since this energy is gradually transferred to the muscle and used for gonadal development in the forthcoming year. The occurrence of ripening individuals on the inner continental shelf in January suggests that these fish either rapidly move into estuaries to spawn by February-March or they remain on the inner shelf to spawn, or

  18. Necator americanus Infection: A Possible Cause of Altered Dendritic Cell Differentiation and Eosinophil Profile in Chronically Infected Individuals

    PubMed Central

    Fujiwara, Ricardo T.; Cançado, Guilherme G. L.; Freitas, Paula A.; Santiago, Helton C.; Massara, Cristiano Lara; dos Santos Carvalho, Omar; Corrêa-Oliveira, Rodrigo; Geiger, Stefan M.; Bethony, Jeffrey

    2009-01-01

    Background Hookworms survive for several years (5 to 7 years) in the host lumen, inducing a robust but largely ineffective immune response. Among the most striking aspects of the immune response to hookworm (as with many other helminths) is the ablation of parasite-specific T cell proliferative response (hyporesponsiveness). While the role of the adaptive immune response in human helminth infection has been well investigated, the role of the innate immune responses (e.g., dendritic cells and eosinophils) has received less attention and remains to be clearly elucidated. Methodology/Principal Findings We report on the differentiation/maturation of host dendritic cells in vitro and the eosinophil activation/function associated with human hookworm infection. Mature DCs (mDCs) from Necator americanus (Necator)–infected individuals showed an impaired differentiation process compared to the mDCs of non-infected individuals, as evidenced by the differential expression of CD11c and CD14. These same hookworm-infected individuals also presented significantly down-regulated expression of CD86, CD1a, HLA-ABC, and HLA-DR. The lower expression of co-stimulatory and antigen presentation molecules by hookworm-infected–derived mDCs was further evidenced by their reduced ability to induce cell proliferation. We also showed that this alternative DC differentiation is partially induced by excreted-secreted hookworm products. Conversely, eosinophils from the same individuals showed a highly activated status, with an upregulation of major cell surface markers. Antigen-pulsed eosinophils from N. americanus–infected individuals induced significant cell proliferation of autologous PBMCs, when compared to non-infected individuals. Conclusion Chronic N. americanus infection alters the host's innate immune response, resulting in a possible modulation of the maturation process of DCs, a functional change that may diminish their ability for antigen presentation and thus contribute to the

  19. The effects of hibernation and captivity on glucose metabolism and thyroid hormones in American black bear (Ursus americanus).

    PubMed

    McCain, Stephanie; Ramsay, Ed; Kirk, Claudia

    2013-06-01

    American black bears (Ursus americanus) have been shown to become transiently insulin resistant and hypothyroid during winter, but no studies have investigated these changes in long-term captive bears or in bears which remain awake year-round. Wild, captive hibernating, and captive nonhibernating bears were evaluated at times corresponding to three of their major physiologic stages: fall (hyperphagic stage), winter (hibernation stage), and summer (normal activity stage). Combined insulin and glucose tolerance tests and thyroid hormone profiles were performed on all bears during each stage. All three groups of bears had evidence of insulin resistance during the winter, as compared to the summer or fall, based on glucose tolerance curves. Analysis of thyroid hormone concentration varied and distinct patterns or similarities were not apparent. While obesity in captive American black bears is multifactorial, the finding that, regardless of their ability to hibernate, captive bears retain similar physiology to their wild counterparts indicates that captive bears' complex physiologic changes need to be addressed in their management.

  20. Aerococcus viridans expression of Cpn60 is associated with virulence during infection of the American lobster, Homarus americanus Milne Edwards.

    PubMed

    Clark, K F; Greenwood, S J

    2011-11-01

    The Gram-positive bacterium Aerococcus viridans var. homari is a well-documented causative agent of the lethal systemic disease gaffkemia in both the American lobster, Homarus americanus, and the European lobster, Homarus gammarus. Previous phenotypic characterization has been unsuccessful at differentiating avirulent from virulent strains without performing lethal animal infection trials. Recent genetic characterization of A. viridans strains through 16S rRNA sequencing and random amplification of polymorphic DNA fingerprinting has revealed the presence of two subtypes. However, subtype 1 contains both virulent and avirulent strains which are genetically identical. The purpose of this study was to determine the proteomic mediators of virulence in A. viridans. Quantitative proteomic mapping of these two strains has revealed 29 differentially expressed protein spots, seven of which are only expressed in the virulent strain and could act as virulence factors. One protein, chaperonin 60 (Cpn60), is uniquely expressed in the virulent strain and has been shown to act as a virulence factor in many other bacteria. The proteomic mapping strategy employed in this study is the first to show phenotypic differences between virulent and avirulent strains. Cpn60 expression represents a potentially useful tool for identifying the virulent strains of A. viridans in epidemiological studies.

  1. Grizzly bears (Ursus arctos horribilis) and black bears (Ursus americanus) prevent trabecular bone loss during disuse (hibernation).

    PubMed

    McGee-Lawrence, Meghan E; Wojda, Samantha J; Barlow, Lindsay N; Drummer, Thomas D; Castillo, Alesha B; Kennedy, Oran; Condon, Keith W; Auger, Janene; Black, Hal L; Nelson, O Lynne; Robbins, Charles T; Donahue, Seth W

    2009-12-01

    Disuse typically causes an imbalance in bone formation and bone resorption, leading to losses of cortical and trabecular bone. In contrast, bears maintain balanced intracortical remodeling and prevent cortical bone loss during disuse (hibernation). Trabecular bone, however, is more detrimentally affected than cortical bone in other animal models of disuse. Here we investigated the effects of hibernation on bone remodeling, architectural properties, and mineral density of grizzly bear (Ursus arctos horribilis) and black bear (Ursus americanus) trabecular bone in several skeletal locations. There were no differences in bone volume fraction or tissue mineral density between hibernating and active bears or between pre- and post-hibernation bears in the ilium, distal femur, or calcaneus. Though indices of cellular activity level (mineral apposition rate, osteoid thickness) decreased, trabecular bone resorption and formation indices remained balanced in hibernating grizzly bears. These data suggest that bears prevent bone loss during disuse by maintaining a balance between bone formation and bone resorption, which consequently preserves bone structure and strength. Further investigation of bone metabolism in hibernating bears may lead to the translation of mechanisms preventing disuse-induced bone loss in bears into novel treatments for osteoporosis.

  2. Magnetic resonance imaging diagnosis of intervertebral disc disease and myelomalacia in an American black bear (Ursus americanus).

    PubMed

    Knafo, S Emmanuelle; Divers, Stephen J; Rech, Raquel; Platt, Simon R

    2012-06-01

    A 23-yr-old black bear (Ursus americanus) was examined because of paralysis of unknown duration. The precise onset of clinical signs was unknown as a result of seasonal torpor. The bear was immobilized and transported to a university veterinary teaching hospital for further evaluation and treatment. Radiography revealed increased mineral opacity and ventral bridging across vertebral segments T8-11. Magnetic resonance imaging demonstrated dorsal and ventral compression of the spinal cord at T8-9. Given the bear's advanced age, the unknown duration of spinal cord compression, unknown presence of deep pain perception, and thus an unknown prognosis for surgical success, euthanasia was elected. Postmortem examination revealed severe spondylosis deformans from T7 to L3 and dorsal extradural extruded disc material in the area of T8-9. Histopathology demonstrated the dorsal horns of the spinal cord at T9 were replaced by foamy macrophages extending into the dorsal and lateral funiculi of the white matter compatible with focal, severe, chronic myelomalacia. This is the first report of intervertebral disc disease and myelomalacia diagnosed using MRI in a large carnivore.

  3. Fatal hepatic sarcocystosis in a captive black bear (Ursus americanus) associated with Sarcocystis canis-like infection.

    PubMed

    Davies, Jennifer L; Haldorson, Gary J; Bradway, Dan S; Britton, Ann P

    2011-03-01

    Fatal hepatic sarcocystosis was diagnosed in a 13-year-old captive black bear (Ursus americanus) with a history of acute onset of vomiting, polyuria, polydipsia, and bilirubinuria. Gross lesions included severe icterus, multisystemic hemorrhage, and gall bladder edema. The most significant microscopic lesion was severe necrotizing hepatitis with intralesional protozoa that reproduced by endopolygeny consistent with a Sarcocystis spp. Infrequent microglial nodules were randomly scattered within the white matter of the cerebral cortices, thalamus, and brainstem, but intralesional protozoal schizonts were not observed. In the liver, immunohistochemistry was positive for Sarcocystis spp. and negative for Toxoplasma gondii and Neospora spp. Positive staining was not observed in the brain. Genus-specific polymerase chain reaction (PCR) amplification of the 18S ribosomal RNA gene was performed on formalin-fixed, paraffin-embedded sections of liver and brain; in both tissues, PCR was positive for Sarcocystis spp. Sequence analysis of the PCR amplicons revealed 100% identity to the published sequences of Sarcocystis canis and Sarcocystis arctosi.

  4. First evidence for slave rebellion: enslaved ant workers systematically kill the brood of their social parasite protomognathus americanus.

    PubMed

    Achenbach, Alexandra; Foitzik, Susanne

    2009-04-01

    During the process of coevolution, social parasites have evolved sophisticated strategies to exploit the brood care behavior of their social hosts. Slave-making ant queens invade host colonies and kill or eject all adult host ants. Host workers, which eclose from the remaining brood, are tricked into caring for the parasite brood. Due to their high prevalence and frequent raids, following which stolen host broods are similarly enslaved, slave-making ants exert substantial selection upon their hosts, leading to the evolution of antiparasite adaptations. However, all host defenses shown to date are active before host workers are parasitized, whereas selection was thought to be unable to act on traits of already enslaved hosts. Yet, here we demonstrate the rebellion of enslaved Temnothorax workers, which kill two-thirds of the female pupae of the slave-making ant Protomognathus americanus. Thereby, slaves decrease the long-term parasite impact on surrounding related host colonies. This novel antiparasite strategy of enslaved workers constitutes a new level in the coevolutionary battle after host colony defense has failed. Our discovery is analogous to recent findings in hosts of avian brood parasites where perfect mimicry of parasite eggs leads to the evolution of chick recognition as a second line of defense.

  5. Myostatin from the American lobster, Homarus americanus: Cloning and effects of molting on expression in skeletal muscles.

    PubMed

    MacLea, Kyle S; Covi, Joseph A; Kim, Hyun-Woo; Chao, Erica; Medler, Scott; Chang, Ernest S; Mykles, Donald L

    2010-12-01

    A cDNA encoding a myostatin (Mstn)-like gene from an astacuran crustacean, Homarus americanus, was cloned and characterized. Mstn inhibits skeletal muscle growth in vertebrates and may play a role in crustacean muscle as a suppressor of protein synthesis. Sequence analysis and three-dimensional modeling of the Ha-Mstn protein predicted a high degree of conservation with vertebrate and other invertebrate myostatins. Qualitative polymerase chain reaction (PCR) demonstrated ubiquitous expression of transcript in all tissues, including skeletal muscles. Quantitative PCR analysis was used to determine the effects of natural molting and eyestalk ablation (ESA) on Ha-Mstn expression in the cutter claw (CT) and crusher claw (CR) closer muscles and deep abdominal (DA) muscle. In intermolt lobsters, the Ha-Mstn mRNA level in the DA muscle was significantly lower than the mRNA levels in the CT and CR muscles. Spontaneous molting decreased Ha-Mstn mRNA during premolt, with the CR muscle, which is composed of slow-twitch (S₁) fibers, responding preferentially (82% decrease) to the atrophic signal compared to fast fibers in CT (51% decrease) and DA (69% decrease) muscles. However, acute increases in circulating ecdysteroids caused by ESA had no effect on Ha-Mstn mRNA levels in the three muscles. These data indicate that the transcription of Ha-Mstn is differentially regulated during the natural molt cycle and it is an important regulator of protein turnover in molt-induced claw muscle atrophy.

  6. First report of piscine nodavirus infecting wild winter flounder Pleuronectes americanus in Passamaquoddy Bay, New Brunswick, Canada.

    PubMed

    Barke, Duane E; MacKinnon, Ann-Margaret; Boston, Linda; Burt, Michael D B; Cone, David K; Speare, David J; Griffiths, Steve; Cook, Marcia; Ritchie, Rachael; Olivier, Gilles

    2002-05-10

    Piscine nodaviruses (Betanodaviridae) are frequently reported from a variety of cultured and wild finfishes. These non-enveloped, single-stranded RNA virions cause viral encephalopathy and retinopathy (VER), also known as viral nervous necrosis (VNN) or fish encephalitis. Recently, nodavirus infections have posed serious problems for larval and juvenile cultured halibut Hippoglossus hippoglossus in Norway and Scotland. To date, no such viruses have been described from any cultured or wild pleuronectid in Atlantic Canada. Obviously, there exists a need to survey wild populations of pleuronectids to assess the risk of potential transfer of nodavirus from wild to caged fishes. This paper presents the results of monthly surveys (April 2000 to March 2001) of viruses from wild winter flounder Pleuronectes americanus collected from Passamaquoddy Bay, New Brunswick, Canada. Tissue samples from wild flounder were screened initially on commercial cell lines (EPC, SSN-1, SHK and CHSE-214) for any evidence of cytopathic effect (CPE). After confirmation of CPE, nodavirus identification was achieved using reverse transcription polymerase chain reaction (RT-PCR) analysis. We detected nodavirus from only 1 out of 440 flounder (0.23%) examined. This is the first report of piscine nodavirus isolated from wild winter flounder in Atlantic Canada, and although this prevalence may seem low, we discuss the implications of this finding for Canada's emerging halibut aquaculture industry.

  7. Low-salinity stress in the American lobster, Homarus americanus, after chronic sublethal exposure to cadmium: Biochemical effects

    NASA Astrophysics Data System (ADS)

    Gould, E.

    1980-03-01

    Lobsters (Homarus americanus) were exposed to cadmium (6 µg l-1, 30 days) in flowing seawater, then held for 7 days in aerated “clean ” seawater at either ambient (27 ‰) or low (17 ‰) salinity. Cadmium exposure alone (ambient salinity) induced a general elevation of enzyme activity (heart, antennal gland, and muscle MDH; heart LDH and GPI), despite the probability of some clearance of cadmium from body tissues during the “clean ” seawater holding period. Low-salinity alone (non-exposed lobsters) caused a decrease of enzyme activity (AAT, LDH, GPI, PK) in most tissues examined, except for tail muscle IDH, the activity of which was increased, and MDH, which was significantly elevated above ambient controls in all tissues except heart. Most low-salinity effects were observed in tail muscle, and most cadmium effects, in heart; low-salinity effects outnumbered cadmium stress by nine to four. In heart and tail muscle of cadmium-exposed lobsters held at low salinity, each of the two stresses apparently operated to nullify the other's effects. The most prominent single biochemical response to these sublethal stresses was the elevation of MDH activity. The ratio MDH: LDH gave the clearest indication of overall relative stress.

  8. Stress effect of different temperatures and air exposure during transport on physiological profiles in the American lobster Homarus americanus.

    PubMed

    Lorenzon, S; Giulianini, P G; Martinis, M; Ferrero, E A

    2007-05-01

    Homarus americanus is an important commercial species that can survive 2-3 days out of water if kept cool and humid. Once caught for commercial purpose and shipped around the world, a lobster is likely to be subjected to a number of stressors, including emersion and air exposure, hypoxia, temperature changes and handling. This study focused on the effect of transport stress and specifically at different animal body temperature (6 and 15 degrees C) and air exposure during commercial transport and recovery process in water. Animals were monitored, by hemolymph bleeding, at different times: 0 h (arrival time at plant) 3 h, 12 h, 24 h and 96 h after immersion in the stocking tank with a water temperature of 6.5+/-1.5 degrees C. We analysed the effects by testing some physiological variables of the hemolymph: glucose, cHH, lactate, total protein, cholesterol, triglycerides, chloride and calcium concentration, pH and density. All these variables appeared to be influenced negatively by high temperature both in average of alteration from the physiological value and in recovering time. Blood glucose, lactate, total protein, cholesterol were significantly higher in the group with high body temperature compared to those with low temperature until 96 h after immersion in the recovery tank.

  9. 1-/sup 14/C-n-hexadecane disposition in the spiny lobster, Panulirus argus and the American lobster, Homarus americanus

    SciTech Connect

    Little, P.J.; James, M.O.; Foureman, G.L.; Weatherby, R.P.; Bend, J.R.

    1986-05-01

    1-/sup 14/C-n-hexadecane, a model compound for the non-volatile aliphatic hydrocarbon components of crude oil, was administered by intrapericardial injection to the spiny lobster, Panulirus argus, and the clawed or American lobster, Homarus americanus. Experiments were conducted in Florida (spiny lobster) and Maine (American lobster). The animals were sacrificed at various times from 0.5 hr to 8 wks after administration of the dose. The tissues and fluids were analyzed for /sup 14/C content by digestion or catalytic oxidation and liquid scintillation counting. Selected tissues (hepatopancreas, tail muscle and hemolymph) were extracted with ethyl acetate to allow quantitation of the unmetabolized n-hexadecane by thin layer chromatography. n-Hexadecane-derived radioactivity was very persistent in both the spiny lobster (t1/2 = 4.6 wk) and the American lobster (t1/2 = 11.2 wk). In both lobsters, the hepatopancreas (HP) acquired the highest specific activity and the tail muscle had the longest half life for elimination from an individual tissue. Although hexadecane was metabolized more rapidly in the HP of the spiny lobster than in the HP of the American lobster, unmetabolized hexadecane persisted in the HPs of both species for at least 8 weeks after the dose (the longest time studied).

  10. Copper-metallothioneins in the American lobster, Homarus americanus: potential role as Cu(I) donors to apohemocyanin

    SciTech Connect

    Brouwer, M.; Whaling, P.; Engel, D.W.

    1986-03-01

    The physiological function of copper(I)-metallothionein is not well understood. The respiratory function of hemocyanin, a copper(I)-containing respiratory protein found in the hemolymph of many invertebrates, has been known a long time. However, the mechanism by which Cu(I) is inserted into the oxygen-binding site of apohemocyanin is completely unknown. This investigation tests that hypothesis that copper(I)-metallothionein may act as a Cu(I) donor to apohemocyanin. To this end, copper-binding proteins and hemocyanin were purified from the digestive gland and hemolymph of the American lobster, Homarus americanus. In the presence of ..beta..-mercaptoethanol, the copper-binding proteins can be resolved into three components of DEAE-cellulose. The first two have been characterized as metallothioneins. The cysteine content of the third component is half of that of components I and II. The purified proteins are not capable of transferring Cu(I) to the active sites of completely copper-free apohemocyanin. They are capable, however, of transferring Cu(I) to active sites of hemocyanin containing reduced amounts of Cu(I), suggesting that the conformational state of hemocyanin is the determining factor in the Cu(I) transfer mechanism.

  11. Forces generated during stretch in the heart of the lobster Homarus americanus are anisotropic and are altered by neuromodulators.

    PubMed

    Dickinson, E S; Johnson, A S; Ellers, O; Dickinson, P S

    2016-04-15

    Mechanical and neurophysiological anisotropies mediate three-dimensional responses of the heart of ITALIC! Homarus americanus Although hearts ITALIC! in vivoare loaded multi-axially by pressure, studies of invertebrate cardiac function typically use uniaxial tests. To generate whole-heart length-tension curves, stretch pyramids at constant lengthening and shortening rates were imposed uniaxially and biaxially along longitudinal and transverse axes of the beating whole heart. To determine whether neuropeptides that are known to modulate cardiac activity in ITALIC! H. americanusaffect the active or passive components of these length-tension curves, we also performed these tests in the presence of SGRNFLRFamide (SGRN) and GYSNRNYLRFamide (GYS). In uniaxial and biaxial tests, both passive and active forces increased with stretch along both measurement axes. The increase in passive forces was anisotropic, with greater increases along the longitudinal axis. Passive forces showed hysteresis and active forces were higher during lengthening than shortening phases of the stretch pyramid. Active forces at a given length were increased by both neuropeptides. To exert these effects, neuropeptides might have acted indirectly on the muscle via their effects on the cardiac ganglion, directly on the neuromuscular junction, or directly on the muscles. Because increases in response to stretch were also seen in stimulated motor nerve-muscle preparations, at least some of the effects of the peptides are likely peripheral. Taken together, these findings suggest that flexibility in rhythmic cardiac contractions results from the amplified effects of neuropeptides interacting with the length-tension characteristics of the heart.

  12. Crystallization and preliminary X-ray analysis of Na-SAA-2 from the human hookworm parasite Necator americanus.

    PubMed

    Asojo, Oluwatoyin A; Goud, Gaddam N; Zhan, Bin; Ordonez, Katherine; Sedlacek, Meghan; Homma, Kohei; Deumic, Vehid; Gupta, Richi; Brelsford, Jill; Price, Merelyn K; Ngamelue, Michelle N; Hotez, Peter J

    2010-02-01

    Human hookworms are among the most pathogenic soil-transmitted helminths. These parasitic nematodes have co-evolved with the host and are able to maintain a high worm burden for decades without killing the human host. However, it is possible to develop vaccines against laboratory-challenge hookworm infections using either irradiated third-state infective larvae (L3) or enzymes from the adult parasites. In an effort to control hookworm infection globally, the Human Hookworm Vaccine Initiative, a product-development partnership with the Sabin Vaccine Institute to develop new control tools including vaccines, has identified a battery of protein antigens, including surface-associated antigens (SAAs) from L3. SAA proteins are characterized by a 13 kDa conserved domain of unknown function. SAA proteins are found on the surface of infective L3 stages (and some adult stages) of different nematode parasites, suggesting that they may play important roles in these organisms. The atomic structures and function of SAA proteins remain undetermined and in an effort to remedy this situation recombinant Na-SAA-2 from the most prevalent human hookworm parasite Necator americanus has been expressed, purified and crystallized. Useful X-ray data have been collected to 2.3 A resolution from a crystal that belonged to the monoclinic space group C2 with unit-cell parameters a = 73.88, b = 35.58, c = 42.75 A, beta = 116.1 degrees .

  13. Identification and phylogenetic analysis of Dirofilaria ursi (Nematoda: Filarioidea) from Wisconsin black bears (Ursus americanus) and its Wolbachia endosymbiont.

    PubMed

    Michalski, Michelle L; Bain, Odile; Fischer, Kerstin; Fischer, Peter U; Kumar, Sanjay; Foster, Jeremy M

    2010-04-01

    Dirofilaria ursi is a filarial nematode of American black bears (Ursus americanus Pallas, 1780) that is vectored by black flies (Simuliidae) in many parts of the United States. In northwestern Wisconsin, the prevalence of microfilaremic bears during the fall hunting season was 21% (n = 47). Unsheathed blood microfilariae from Wisconsin bears possess characters consistent with the original description of D. ursi, as do adult worms observed histologically and grossly. Immunohistochemistry was used to identify the Wolbachia endosymbiont in the hypodermis and lateral cords of an adult female D. ursi. Amplification of wsp, gatB, coxA, fbpA, and ftsZ bacterial sequences from parasite DNA confirmed the presence of Wolbachia, and molecular phylogenetic analysis of the Wolbachia ftsZ gene groups the endosymbiont with Wolbachia from D. immitis and D. repens. Phylogenetic analysis of D. ursi 5s rDNA sequence confirms the morphological observations grouping this parasite as a member of Dirofilaria, and within the Dirofilaria - Onchocerca clade of filarial nematodes. This is the first report of Wolbachia characterization and molecular phylogeny information for D. ursi.

  14. rRNA operons and genome size of 'Candidatus Liberibacter americanus', a bacterium associated with citrus huanglongbing in Brazil.

    PubMed

    Wulff, N A; Eveillard, S; Foissac, X; Ayres, A J; Bové, J-M

    2009-08-01

    Huanglongbing is one of the most severe diseases of citrus worldwide and is associated with 'Candidatus (Ca.) Liberibacter africanus' in Africa, 'Ca. Liberibacter asiaticus' in Asia and the Americas (Brazil, USA and Cuba) and 'Ca. Liberibacter americanus' (Lam) in Brazil. In the absence of axenic cultures, genetic information on liberibacters is scarce. The sequences of the entire 23S rRNA and 5S rRNA genes from Lam have now been obtained, using a consensus primer designed on known tRNAMet sequences of rhizobia. The size of the Lam genome was determined by PFGE, using Lam-infected periwinkle plants for bacterial enrichment, and was found to be close to 1.31 Mbp. In order to determine the number of ribosomal operons on the Lam genome, probes designed to detect the 16S rRNA gene and the 3' end of the 23S rRNA gene were developed and used for Southern hybridization with I-CeuI-treated genomic DNA. Our results suggest that there are three ribosomal operons in a circular genome. Lam is the first liberibacter species for which such data are available.

  15. A New PCR-Based Method Shows That Blue Crabs (Callinectes sapidus (Rathbun)) Consume Winter Flounder (Pseudopleuronectes americanus (Walbaum))

    PubMed Central

    Collier, Jackie L.; Fitzgerald, Sean P.; Hice, Lyndie A.; Frisk, Michael G.; McElroy, Anne E.

    2014-01-01

    Winter flounder (Pseudopleuronectes americanus) once supported robust commercial and recreational fisheries in the New York (USA) region, but since the 1990s populations have been in decline. Available data show that settlement of young-of-the-year winter flounder has not declined as sharply as adult abundance, suggesting that juveniles are experiencing higher mortality following settlement. The recent increase of blue crab (Callinectes sapidus) abundance in the New York region raises the possibility that new sources of predation may be contributing to juvenile winter flounder mortality. To investigate this possibility we developed and validated a method to specifically detect winter flounder mitochondrial control region DNA sequences in the gut contents of blue crabs. A survey of 55 crabs collected from Shinnecock Bay (along the south shore of Long Island, New York) in July, August, and September of 2011 showed that 12 of 42 blue crabs (28.6%) from which PCR-amplifiable DNA was recovered had consumed winter flounder in the wild, empirically supporting the trophic link between these species that has been widely speculated to exist. This technique overcomes difficulties with visual identification of the often unrecognizable gut contents of decapod crustaceans, and modifications of this approach offer valuable tools to more broadly address their feeding habits on a wide variety of species. PMID:24454797

  16. A new PCR-based method shows that blue crabs (Callinectes sapidus (Rathbun)) consume winter flounder (Pseudopleuronectes americanus (Walbaum)).

    PubMed

    Collier, Jackie L; Fitzgerald, Sean P; Hice, Lyndie A; Frisk, Michael G; McElroy, Anne E

    2014-01-01

    Winter flounder (Pseudopleuronectes americanus) once supported robust commercial and recreational fisheries in the New York (USA) region, but since the 1990s populations have been in decline. Available data show that settlement of young-of-the-year winter flounder has not declined as sharply as adult abundance, suggesting that juveniles are experiencing higher mortality following settlement. The recent increase of blue crab (Callinectes sapidus) abundance in the New York region raises the possibility that new sources of predation may be contributing to juvenile winter flounder mortality. To investigate this possibility we developed and validated a method to specifically detect winter flounder mitochondrial control region DNA sequences in the gut contents of blue crabs. A survey of 55 crabs collected from Shinnecock Bay (along the south shore of Long Island, New York) in July, August, and September of 2011 showed that 12 of 42 blue crabs (28.6%) from which PCR-amplifiable DNA was recovered had consumed winter flounder in the wild, empirically supporting the trophic link between these species that has been widely speculated to exist. This technique overcomes difficulties with visual identification of the often unrecognizable gut contents of decapod crustaceans, and modifications of this approach offer valuable tools to more broadly address their feeding habits on a wide variety of species.

  17. The effects of walking on heart rate, ventilation rate and acid-base status in the lobster homarus americanus

    PubMed

    Rose; Wilkens; Walker

    1998-09-01

    American lobsters Homarus americanus were exercised on an underwater treadmill at speeds from 1.7 to 8 m min-1 to determine the effects of exercise on heart rate, ventilation rate and acid-base status. Heart and ventilation rates showed almost instantaneous increases at the start of exercise, but the magnitude of the increase was not related to speed. Maximum heart rate was approximately 80-90 beats min-1 and maximum ventilation rate was 175-180 beats min-1 at all speeds tested. Exercise at all speeds caused a decrease in haemolymph pH, with the acidosis after exercise at 8 m min-1 being significantly greater than at the other three speeds. Concomitant with this acidosis was a large increase in partial pressure of carbon dioxide, with the largest increase occurring after exercise at 8 m min-1. The concentration of lactate in the haemolymph increased to similar levels at all speeds of walking. Davenport analysis indicates that the acidosis was predominantly respiratory in nature. Although it was anticipated that heart and ventilation rates would show increases proportional to the speed of exercise, this was not the case. Rather, the responses were fixed regardless of walking speed. The reason for this phenomenon remains unexplained.

  18. 1-14C-n-hexadecane disposition in the spiny lobster, Panulirus argus and the American lobster, Homarus americanus.

    PubMed

    Little, P J; James, M O; Foureman, G L; Weatherby, R P; Bend, J R

    1986-01-01

    1-14C-n-hexadecane, a model compound for the non-volatile aliphatic hydrocarbon components of crude oil, was administered by intrapericardial injection to the spiny lobster, Panulirus argus, and the clawed or American lobster, Homarus americanus. Experiments were conducted in Florida (spiny lobster) and Maine (American lobster). The animals were sacrificed at various times from 0.5 hr to 8 wks after administration of the dose. The tissues and fluids were analyzed for 14C content by digestion or catalytic oxidation and liquid scintillation counting. Selected tissues (hepatopancreas, tail muscle and hemolymph) were extracted with ethyl acetate to allow quantitation of the unmetabolized n-hexadecane by thin layer chromatography. n-Hexadecane-derived radioactivity was very persistent in both the spiny lobster (t1/2 = 4.6 wk) and the American lobster (t1/2 = 11.2 wk). In both lobsters, the hepatopancreas (HP) acquired the highest specific activity and the tail muscle had the longest half life for elimination from an individual tissue. Although hexadecane was metabolized more rapidly in the HP of the spiny lobster than in the HP of the American lobster, unmetabolized hexadecane persisted in the HPs of both species for at least 8 weeks after the dose (the longest time studied).

  19. Mass Spectral Charting of Neuropeptidomic Expression in the Stomatogastric Ganglion at Multiple Developmental Stages of the Lobster Homarus americanus

    PubMed Central

    2012-01-01

    The stomatogastric nervous system (STNS) of the American lobster Homarus americanus serves as a useful model for studies of neuromodulatory substances such as peptides and their roles in the generation of rhythmic behaviors. As a central component of the STNS, the stomatogastric ganglion (STG) is rich in neuropeptides and contains well-defined networks of neurons, serving as an excellent model system to study the effect of neuropeptides on the maturation of neural circuits. Here, we utilize multiple mass spectrometry (MS)-based techniques to study the neuropeptide content and abundance in the STG tissue as related to the developmental stage of the animal. Capillary electrophoresis (CE)-MS was employed to unambiguously identify low abundance neuropeptide complements, which were not fully addressed using previous methods. In total, 35 neuropeptides from 7 different families were detected in the tissue samples. Notably, 10 neuropeptides have been reported for the first time in this study. In addition, we utilized a relative quantitation method to compare neuropeptidomic expression at different developmental stages and observed sequential appearance of several neuropeptides. Multiple isoforms within the same peptide family tend to show similar trends of changes in relative abundance during development. We also determined that the relative abundances of tachykinin peptides increase as the lobster grows, suggesting that the maturation of circuit output may be influenced by the change of neuromodulatory input into the STG. Collectively, this study expands our knowledge about neuropeptides in the crustacean STNS and provides useful information about neuropeptide expression in the maturation process. PMID:22860213

  20. Effects of temperature regime through premetamorphic ontogeny on shape of the chondrocranium in the American toad, Anaxyrus americanus.

    PubMed

    Jorgensen, Michael E; Sheil, Christopher A

    2008-07-01

    If one considers the substantial amount of information that exists about phenotypic plasticity in amphibians, it is surprising that few studies have examined abiotic factors that influence phenotype through ontogeny. Phenotypic change and stability of morphology are artifacts of organisms that bear significant relevance to evolution within and among taxonomic groups. Here, we examine development as a phenotypically plastic aspect of larval anurans. Fertilized eggs of the American Toad, Anaxyrus (= Bufo) americanus (Holbrook, 1836), were obtained from two pairs of adults, and larvae were reared in four temperature treatments (constant Mean, constant High, constant Low, and Fluctuating regime [Low night-High day]); developmental series were collected from each treatment, representing larvae of this species from Gosner Stages 28-40. Cleared and stained larvae were analyzed with landmark-based geometric morphometric methods to facilitate examination of differences in overall shape change of the larval chondrocranium through ontogeny, as a result of developmental temperature or temperature regime. Changes in shape of the chondrocranium and in amount and direction of phenotypic change through ontogeny were found in response to temperature treatment and temperature regime. Mean chondrocranial shape of the Fluctuating regime was more similar to the consensus shape of the overall data set than were those of all other treatments. Given that differences in amount and direction of shape change were observed among these treatments and throughout ontogeny, one should consider the affects of abiotic factors (such as temperature) when rearing larval anurans for studies of developmental morphology.

  1. Expression, purification, and characterization of the Necator americanus aspartic protease-1 (Na-APR-1 (M74)) antigen, a component of the bivalent human hookworm vaccine

    PubMed Central

    Seid, Christopher A; Curti, Elena; Jones, R Mark; Hudspeth, Elissa; Rezende, Wanderson; Pollet, Jeroen; Center, Lori; Versteeg, Leroy; Pritchard, Sonya; Musiychuk, Konstantin; Yusibov, Vidadi; Hotez, Peter J; Bottazzi, Maria Elena

    2015-01-01

    Over 400 million people living in the world's poorest developing nations are infected with hookworms, mostly of the genus Necator americanus. A bivalent human hookworm vaccine composed of the Necator americanus Glutathione S-Transferase-1 (Na-GST-1) and the Necator americanus Aspartic Protease-1 (Na-APR-1 (M74)) is currently under development by the Sabin Vaccine Institute Product Development Partnership (Sabin PDP). Both monovalent vaccines are currently in Phase 1 trials. Both Na-GST-1 and Na-APR-1 antigens are expressed as recombinant proteins. While Na-GST-1 was found to express with high yields in Pichia pastoris, the level of expression of Na-APR-1 in this host was too low to be suitable for a manufacturing process. When the tobacco plant Nicotiana benthamiana was evaluated as an expression system, acceptable levels of solubility, yield, and stability were attained. Observed expression levels of Na-APR-1 (M74) using this system are ∼300 mg/kg. Here we describe the achievements and obstacles encountered during process development as well as characterization and stability of the purified Na-APR-1 (M74) protein and formulated vaccine. The expression, purification and analysis of purified Na-APR-1 (M74) protein obtained from representative 5 kg reproducibility runs performed to qualify the Na-APR-1 (M74) production process is also presented. This process has been successfully transferred to a pilot plant and a 50 kg scale manufacturing campaign under current Good Manufacturing Practice (cGMP) has been performed. The 50 kg run has provided a sufficient amount of protein to support the ongoing hookworm vaccine development program of the Sabin PDP. PMID:25905574

  2. Expression, purification, and characterization of the Necator americanus aspartic protease-1 (Na-APR-1 (M74)) antigen, a component of the bivalent human hookworm vaccine.

    PubMed

    Seid, Christopher A; Curti, Elena; Jones, R Mark; Hudspeth, Elissa; Rezende, Wanderson; Pollet, Jeroen; Center, Lori; Versteeg, Leroy; Pritchard, Sonya; Musiychuk, Konstantin; Yusibov, Vidadi; Hotez, Peter J; Bottazzi, Maria Elena

    2015-01-01

    Over 400 million people living in the world's poorest developing nations are infected with hookworms, mostly of the genus Necator americanus. A bivalent human hookworm vaccine composed of the Necator americanus Glutathione S-Transferase-1 (Na-GST-1) and the Necator americanus Aspartic Protease-1 (Na-APR-1 (M74)) is currently under development by the Sabin Vaccine Institute Product Development Partnership (Sabin PDP). Both monovalent vaccines are currently in Phase 1 trials. Both Na-GST-1 and Na-APR-1 antigens are expressed as recombinant proteins. While Na-GST-1 was found to express with high yields in Pichia pastoris, the level of expression of Na-APR-1 in this host was too low to be suitable for a manufacturing process. When the tobacco plant Nicotiana benthamiana was evaluated as an expression system, acceptable levels of solubility, yield, and stability were attained. Observed expression levels of Na-APR-1 (M74) using this system are ∼300 mg/kg. Here we describe the achievements and obstacles encountered during process development as well as characterization and stability of the purified Na-APR-1 (M74) protein and formulated vaccine. The expression, purification and analysis of purified Na-APR-1 (M74) protein obtained from representative 5 kg reproducibility runs performed to qualify the Na-APR-1 (M74) production process is also presented. This process has been successfully transferred to a pilot plant and a 50 kg scale manufacturing campaign under current Good Manufacturing Practice (cGMP) has been performed. The 50 kg run has provided a sufficient amount of protein to support the ongoing hookworm vaccine development program of the Sabin PDP.

  3. Prediction of a neuropeptidome for the eyestalk ganglia of the lobster Homarus americanus using a tissue-specific de novo assembled transcriptome.

    PubMed

    Christie, Andrew E; Roncalli, Vittoria; Cieslak, Matthew C; Pascual, Micah G; Yu, Andy; Lameyer, Tess J; Stanhope, Meredith E; Dickinson, Patsy S

    2017-03-01

    In silico transcriptome mining is a powerful tool for crustacean peptidome prediction. Using homology-based BLAST searches and a simple bioinformatics workflow, large peptidomes have recently been predicted for a variety of crustaceans, including the lobster, Homarus americanus. Interestingly, no in silico studies have been conducted on the eyestalk ganglia (lamina ganglionaris, medulla externa, medulla interna and medulla terminalis) of the lobster, although the eyestalk is the location of a major neuroendocrine complex, i.e., the X-organ-sinus gland system. Here, an H. americanus eyestalk ganglia-specific transcriptome was produced using the de novo assembler Trinity. This transcriptome was generated from 130,973,220 Illumina reads and consists of 147,542 unique contigs. Eighty-nine neuropeptide-encoding transcripts were identified from this dataset, allowing for the deduction of 62 distinct pre/preprohormones. Two hundred sixty-two neuropeptides were predicted from this set of precursors; the peptides include members of the adipokinetic hormone-corazonin-like peptide, allatostatin A, allatostatin B, allatostatin C, bursicon α, CCHamide, corazonin, crustacean cardioactive peptide, crustacean hyperglycemic hormone (CHH), CHH precursor-related peptide, diuretic hormone 31, diuretic hormone 44, eclosion hormone, elevenin, FMRFamide-like peptide, glycoprotein hormone α2, glycoprotein hormone β5, GSEFLamide, intocin, leucokinin, molt-inhibiting hormone, myosuppressin, neuroparsin, neuropeptide F, orcokinin, orcomyotropin, pigment dispersing hormone, proctolin, pyrokinin, red pigment concentrating hormone, RYamide, short neuropeptide F, SIFamide, sulfakinin, tachykinin-related peptide and trissin families. The predicted peptides expand the H. americanus eyestalk ganglia neuropeptidome approximately 7-fold, and include 78 peptides new to the lobster. The transcriptome and predicted neuropeptidome described here provide new resources for investigating peptidergic

  4. Mass spectral characterization of peptide transmitters/hormones in the nervous system and neuroendocrine organs of the American lobster Homarus americanus

    PubMed Central

    Ma, Mingming; Chen, Ruibing; Sousa, Gregory L.; Bors, Eleanor K.; Kwiatkowski, Molly; Goiney, Christopher C.; Goy, Michael F.; Christie, Andrew E.; Li, Lingjun

    2008-01-01

    The American lobster Homarus americanus is a decapod crustacean with both high economic and scientific importance. To facilitate physiological investigations of peptide transmitter/hormone function in this species, we have used matrix-assisted laser desorption/ionization Fourier transform mass spectrometry (MALDI-FTMS), matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) and nanoscale liquid chromatography coupled to electrospray ionization quadrupole time-of-flight tandem mass spectrometry (nanoLC-ESI-Q-TOF-MS/MS) to elucidate the peptidome present in its nervous system and neuroendocrine organs. In total, 84 peptides were identified, including 27 previously known H. americanus peptides (e.g. VYRKPPFNGSIFamide [Val1-SIFamide]), 23 peptides characterized previously from other decapods, but new to the American lobster (e.g. pQTFQYSRGWTNamide [Arg7-corazonin]), and 34 new peptides de novo sequenced/detected for the first time in this study. Of particular note are a novel B-type allatostatin (TNWNKFQGSWamide) and several novel FMRFamide-related peptides, including an unsulfated analog of sulfakinin (GGGEYDDYGHLRFamide), two myosuppressins (QDLDHVFLRFamide and pQDLDHVFLRFamide), and a collection of short neuropeptide F isoforms (e.g. DTSTPALRLRFamide, and FEPSLRLRFamide). Our data also include the first detection of multiple tachykinin-related peptides in a non-brachyuran decapod, as well as the identification of potential individual-specific variants of orcokinin and orcomyotropin-related peptide. Taken collectively, our results not only expand greatly the number of known H. americanus neuropeptides, but also provide a framework for future studies on the physiological roles played by these molecules in this commercially and scientifically important species. PMID:18304551

  5. Wound healing during hibernation by black bears (Ursus americanus) in the wild: elicitation of reduced scar formation.

    PubMed

    Iaizzo, Paul A; Laske, Timothy G; Harlow, Henry J; McClay, Carolyn B; Garshelis, David L

    2012-03-01

    Even mildly hypothermic body or limb temperatures can retard healing processes in mammals. Despite this, we observed that hibernating American black bears (Ursus americanus Pallas, 1780) elicit profound abilities in mounting inflammatory responses to infection and/or foreign bodies. In addition, they resolve injuries during hibernation while maintaining mildly hypothermic states (30-35 °C) and without eating, drinking, urinating or defecating. We describe experimental studies on free-ranging bears that document their abilities to completely resolve cutaneous cuts and punctures incurred during or prior to hibernation. We induced small, full-thickness cutaneous wounds (biopsies or incisions) during early denning, and re-biopsied sites 2-3 months later (near the end of denning). Routine histological methods were used to characterize these skin samples. All biopsied sites with respect to secondary intention (open circular biopsies) and primary intention (sutured sites) healed, with evidence of initial eschar (scab) formation, completeness of healed epidermis and dermal layers, dyskeratosis (inclusion cysts), and abilities to produce hair follicles. These healing abilities of hibernating black bears are a clear survival advantage to animals injured before or during denning. Bears are known to have elevated levels of hibernation induction trigger (delta-opioid receptor agonist) and ursodeoxycholic acid (major bile acid within plasma, mostly conjugated with taurine) during hibernation, which may relate to these wound-healing abilities. Further research as to the underlying mechanisms of wound healing during hibernation could have applications in human medicine. Unique approaches may be found to improve healing for malnourished, hypothermic, diabetic and elderly patients or to reduce scarring associated with burns and traumatic injuries.

  6. (Lack of) genetic diversity in immune genes predates glacial isolation in the North American mountain goat (Oreamnos americanus).

    PubMed

    Shafer, Aaron B A; Fan, Chia Wei; Côté, Steeve D; Coltman, David W

    2012-01-01

    The major histocompatibility complex (MHC) plays an important role in an organism's ability to respond to pathogens. Immunogenetic diversity is advantageous as it permits the recognition of more external antigens. For this reason, MHC and immune gene variation are considered a barometer for the genetic health of wild populations. Mountain goats (Oreamnos americanus) were previously shown to have little variation at the MHC Class II Oram-DRB locus, which was attributed to population bottlenecks during the last glacial maximum (LGM). In this paper, we extended the analysis of immunogenetic variability in mountain goats to 5 genes representing the 3 classes of MHC gene (Class I OLA, Class II DRA and DRB, and Class III TNF-α) and the natural resistance-associated macrophage protein. We sequenced approximately 3000 bp from 31 individuals sampled across the range of mountain goats and found very low levels of diversity (1-3 polymorphic sites per gene) with the exception of the Class I Oram-OLA gene. Oram-OLA was nearly 30 times more diverse than the other immune genes and appears to represent a source of increased immunogenetic diversity. This diversity may be attributed to multiple loci, mediated by pathogen exposure, or potentially influenced by social factors. The distribution of SNPs was not associated with refugial history, suggesting that the current distribution of immunogenetic diversity was present prior to the LGM. These data suggest that although they have low levels of diversity at the 4 of 5 immune loci, mountain goats may be better equipped for future climate oscillations and pathogen exposure than previously thought.

  7. Sex, Diet, and the Social Environment: Factors Influencing Hair Cortisol Concentration in Free-Ranging Black Bears (Ursus americanus).

    PubMed

    Lafferty, Diana J R; Laudenslager, Mark L; Mowat, Garth; Heard, Doug; Belant, Jerrold L

    2015-01-01

    Increasingly, measures of glucocorticoid levels (e.g., cortisol), key components of the neuroendocrine stress axis, are being used to measure past hypothalamic-pituitary-adrenal (HPA) activity to index psychological and physiological stress exhibited by wildlife for assessing individual and population-level well-being. However, many intrinsic and extrinsic factors affect HPA activity in animals. Using American black bears (Ursus americanus; n = 116) as an ecological model and hair cortisol concentration (HCC) as an integrative measure of past HPA activity, we evaluated the influence of diet, sex and the social environment on black bear HCC in a free-ranging population that spanned adjoining ecoregions with differing densities of potential conspecific and heterospecific competitors. HCC varied by sex, with female HCC ranging from 0.6 to 10.7 pg/mg (median = 4.5 ± 1.2 mean absolute deviation [MAD]) and male HCC ranging from 0.5 to 35.1 pg/mg (median = 6.2 ± 2.6 MAD). We also observed a three-way interaction among sex, δ14C and ecoregion, which may indicate that some differences in HCC between female and male black bears results from variability in the nutritional needs of larger-bodied males relative to smaller-bodied females, slight differences in food resources use between ecoregions as well as sex-based differences regarding the social environment. Once we understand what drives sex-specific differences in HCC, HCC may aid our understanding of the physiological responses by bears and other wildlife to diverse environmental challenges.

  8. Determining causes of genetic isolation in a large carnivore (Ursus americanus) population to direct contemporary conservation measures

    PubMed Central

    Obbard, Martyn E.; Harnden, Matthew; McConnell, Sabine; Howe, Eric J.; Burrows, Frank G.; White, Bradley N.; Kyle, Christopher J.

    2017-01-01

    The processes leading to genetic isolation influence a population’s local extinction risk, and should thus be identified before conservation actions are implemented. Natural or human-induced circumstances can result in historical or contemporary barriers to gene flow and/or demographic bottlenecks. Distinguishing between these hypotheses can be achieved by comparing genetic diversity and differentiation in isolated vs. continuous neighboring populations. In Ontario, American black bears (Ursus americanus) are continuously distributed, genetically diverse, and exhibit an isolation-by-distance structuring pattern, except on the Bruce Peninsula (BP). To identify the processes that led to the genetic isolation of BP black bears, we modelled various levels of historical and contemporary migration and population size reductions using forward simulations. We compared simulation results with empirical genetic indices from Ontario black bear populations under different levels of geographic isolation, and conducted additional simulations to determine if translocations could help achieve genetic restoration. From a genetic standpoint, conservation concerns for BP black bears are warranted because our results show that: i) a recent demographic bottleneck associated with recently reduced migration best explains the low genetic diversity on the BP; and ii) under sustained isolation, BP black bears could lose between 70% and 80% of their rare alleles within 100 years. Although restoring migration corridors would be the most effective method to enhance long-term genetic diversity and prevent inbreeding, it is unrealistic to expect connectivity to be re-established. Current levels of genetic diversity could be maintained by successfully translocating 10 bears onto the peninsula every 5 years. Such regular translocations may be more practical than landscape restoration, because areas connecting the peninsula to nearby mainland black bear populations have been irreversibly modified

  9. Determining causes of genetic isolation in a large carnivore (Ursus americanus) population to direct contemporary conservation measures.

    PubMed

    Pelletier, Agnès; Obbard, Martyn E; Harnden, Matthew; McConnell, Sabine; Howe, Eric J; Burrows, Frank G; White, Bradley N; Kyle, Christopher J

    2017-01-01

    The processes leading to genetic isolation influence a population's local extinction risk, and should thus be identified before conservation actions are implemented. Natural or human-induced circumstances can result in historical or contemporary barriers to gene flow and/or demographic bottlenecks. Distinguishing between these hypotheses can be achieved by comparing genetic diversity and differentiation in isolated vs. continuous neighboring populations. In Ontario, American black bears (Ursus americanus) are continuously distributed, genetically diverse, and exhibit an isolation-by-distance structuring pattern, except on the Bruce Peninsula (BP). To identify the processes that led to the genetic isolation of BP black bears, we modelled various levels of historical and contemporary migration and population size reductions using forward simulations. We compared simulation results with empirical genetic indices from Ontario black bear populations under different levels of geographic isolation, and conducted additional simulations to determine if translocations could help achieve genetic restoration. From a genetic standpoint, conservation concerns for BP black bears are warranted because our results show that: i) a recent demographic bottleneck associated with recently reduced migration best explains the low genetic diversity on the BP; and ii) under sustained isolation, BP black bears could lose between 70% and 80% of their rare alleles within 100 years. Although restoring migration corridors would be the most effective method to enhance long-term genetic diversity and prevent inbreeding, it is unrealistic to expect connectivity to be re-established. Current levels of genetic diversity could be maintained by successfully translocating 10 bears onto the peninsula every 5 years. Such regular translocations may be more practical than landscape restoration, because areas connecting the peninsula to nearby mainland black bear populations have been irreversibly modified

  10. Kinematics, hydrodynamics and force production of pleopods suggest jet-assisted walking in the American lobster (Homarus americanus).

    PubMed

    Lim, Jeanette L; Demont, M Edwin

    2009-09-01

    The American lobster (Homarus americanus) displays a diverse set of locomotory behaviours that includes tail flips, walking and paddling. Paddling is carried out by the four pairs of paddle-shaped pleopods on the ventral abdomen. Although it is recognized that pleopod-generated fluid flows have some locomotory role in adults, reports on their relative importance in locomotion are inconsistent. This paper integrates experimental kinematics and hydrodynamics of lobster pleopod beating to determine the mechanism and magnitude of pleopod force production. A kinematic analysis of pleopod beating in live lobsters showed that the pleopods execute an adlocomotory metachronal beating pattern. We modelled in vivo pleopod kinematics with a set of simple trigonometric functions, and used these functions to program a mechanical lobster model consisting of motor-driven pleopods on a lobster abdomen exoskeleton. Based on flow visualizations obtained from applying particle image velocimetry to the lobster model, we propose that the unsteady metachronal kinematics of the pleopods can maximize thrust by exploiting forces arising from individual pleopod activity and interactions among adjacent pairs. The pleopods continuously entrain fluid surrounding the lobster and create a caudally directed fluid jet oriented parallel to the substratum. Inputting wake morphology and velocity data into a simplified model for steady jet thrust showed that the pleopods of the lobster model produced 27-54 mN of thrust, which is comparable to the propulsive forces generated by other proficient swimmers. These results suggest that lobster pleopods are capable of producing forces of a magnitude that could assist the walking legs in forward propulsion.

  11. No Excess of Cis-Regulatory Variation Associated with Intraspecific Selection in Wild Pearl Millet (Cenchrus americanus)

    PubMed Central

    Rhoné, Bénédicte; Mariac, Cédric; Couderc, Marie; Berthouly-Salazar, Cécile; Ousseini, Issaka Salia

    2017-01-01

    Several studies suggest that cis-regulatory mutations are the favorite target of evolutionary changes, one reason being that cis-regulatory mutations might have fewer deleterious pleiotropic effects than protein-coding mutations. A review of the process also suggests that this bias towards adaptive cis-regulatory variation might be less pronounced at the intraspecific level compared with the interspecific level. In this study, we assessed the contribution of cis-regulatory variation to adaptation at the intraspecific level using populations of wild pearl millet (Cenchrus americanus ssp. monodii) sampled along an environmental gradient in Niger. From RNA sequencing of hybrids to assess allele-specific expression, we identified genes with cis-regulatory divergence between two parental accessions collected in contrasted environmental conditions. This revealed that ∼15% of transcribed genes showed cis-regulatory variation. Intersecting the gene set exhibiting cis-regulatory variation with the gene set identified as targets of selection revealed no excess of cis-acting mutations among the selected genes. We additionally found no excess of cis-regulatory variation among genes associated with adaptive traits. As our approach relied on methods identifying mainly genes submitted to strong selection pressure or with high phenotypic effect, the contribution of cis-regulatory changes to soft selection or polygenic adaptive traits remains to be tested. However our results favor the hypothesis that enrichment of adaptive cis-regulatory divergence builds up over time. For short evolutionary time-scales, cis-acting mutations are not predominantly involved in adaptive evolution associated with strong selective signal. PMID:28137746

  12. Transfer of benzo(a)pyrene from two invertebrate prey species to the winter flounder, Pleuronectes americanus

    SciTech Connect

    Schnitz, A.R.; Taghon, G.L.

    1995-12-31

    Anthropogenic activities in and around the estuarine environment may introduce compounds with the ability to move through trophic levels, resulting in adverse effects to ecosystems and human health. In order to observe the potential for transfer of the carcinogen benzo(a)pyrene (BaP) and its derivatives from prey organisms to a predator, a simplified benthic food chain was constructed. Winter flounder, Pleuronectes americanus, were fed via gavage either softshell clams, Mya arenaria, or sandworms, Neanthes virens, that had previously been exposed to {sup 14}C-benzo(a)pyrene-contaminated sediments and contained 5.05 ng/g and 5.8 ng/g activity, respectively (wet weight). The fish received doses every 48 hours for a total of 192 hours after which time, all tissues except the gall bladder were examined for the presence of BaP using liquid scintillation spectrometry (LSC). The bile was extracted with chloroform/methanol and analyzed via high performance liquid chromatography (HPLC) and LSC. The flounders that were fed worms demonstrated increased metabolism of the PAH relative to those fed clams, as shown by higher concentrations of polar metabolites in the bile. This corresponds with the higher concentration of metabolites recovered in the worm tissue; more than 95% of the recovered activity was in the form of polar derivatives whereas the activity in the clam tissue was almost completely parent benzo(a)pyrene. As was expected, the BaP metabolites formed by the fish were mediated by the differing abilities of the prey species to derivatize the PAH. Thus, macrofaunal interactions with sedimentary-associated polycyclic aromatic hydrocarbons may be important determinants in the fate and transport of these compounds in the benthos.

  13. The peptide hormone pQDLDHVFLRFamide (crustacean myosuppressin) modulates the Homarus americanus cardiac neuromuscular system at multiple sites.

    PubMed

    Stevens, J S; Cashman, C R; Smith, C M; Beale, K M; Towle, D W; Christie, A E; Dickinson, P S

    2009-12-01

    pQDLDHVFLRFamide is a highly conserved crustacean neuropeptide with a structure that places it within the myosuppressin subfamily of the FMRFamide-like peptides. Despite its apparent ubiquitous conservation in decapod crustaceans, the paracrine and/or endocrine roles played by pQDLDHVFLRFamide remain largely unknown. We have examined the actions of this peptide on the cardiac neuromuscular system of the American lobster Homarus americanus using four preparations: the intact animal, the heart in vitro, the isolated cardiac ganglion (CG), and a stimulated heart muscle preparation. In the intact animal, injection of myosuppressin caused a decrease in heartbeat frequency. Perfusion of the in vitro heart with pQDLDHVFLRFamide elicited a decrease in the frequency and an increase in the amplitude of heart contractions. In the isolated CG, myosuppressin induced a hyperpolarization of the resting membrane potential of cardiac motor neurons and a decrease in the cycle frequency of their bursting. In the stimulated heart muscle preparation, pQDLDHVFLRFamide increased the amplitude of the induced contractions, suggesting that myosuppressin modulates not only the CG, but also peripheral sites. For at least the in vitro heart and the isolated CG, the effects of myosuppressin were dose-dependent (10(-9) to 10(-6) mol l(-1) tested), with threshold concentrations (10(-8)-10(-7) mol l(-1)) consistent with the peptide serving as a circulating hormone. Although cycle frequency, a parameter directly determined by the CG, consistently decreased when pQDLDHVFLRFamide was applied to all preparation types, the magnitudes of this decrease differed, suggesting the possibility that, because myosuppressin modulates the CG and the periphery, it also alters peripheral feedback to the CG.

  14. The peptide hormone pQDLDHVFLRFamide (crustacean myosuppressin) modulates the Homarus americanus cardiac neuromuscular system at multiple sites

    PubMed Central

    Stevens, J. S.; Cashman, C. R.; Smith, C. M.; Beale, K. M.; Towle, D. W.; Christie, A. E.; Dickinson, P. S.

    2009-01-01

    pQDLDHVFLRFamide is a highly conserved crustacean neuropeptide with a structure that places it within the myosuppressin subfamily of the FMRFamide-like peptides. Despite its apparent ubiquitous conservation in decapod crustaceans, the paracrine and/or endocrine roles played by pQDLDHVFLRFamide remain largely unknown. We have examined the actions of this peptide on the cardiac neuromuscular system of the American lobster Homarus americanus using four preparations: the intact animal, the heart in vitro, the isolated cardiac ganglion (CG), and a stimulated heart muscle preparation. In the intact animal, injection of myosuppressin caused a decrease in heartbeat frequency. Perfusion of the in vitro heart with pQDLDHVFLRFamide elicited a decrease in the frequency and an increase in the amplitude of heart contractions. In the isolated CG, myosuppressin induced a hyperpolarization of the resting membrane potential of cardiac motor neurons and a decrease in the cycle frequency of their bursting. In the stimulated heart muscle preparation, pQDLDHVFLRFamide increased the amplitude of the induced contractions, suggesting that myosuppressin modulates not only the CG, but also peripheral sites. For at least the in vitro heart and the isolated CG, the effects of myosuppressin were dose-dependent (10−9 to 10−6 mol l−1 tested), with threshold concentrations (10−8−10−7 mol l−1) consistent with the peptide serving as a circulating hormone. Although cycle frequency, a parameter directly determined by the CG, consistently decreased when pQDLDHVFLRFamide was applied to all preparation types, the magnitudes of this decrease differed, suggesting the possibility that, because myosuppressin modulates the CG and the periphery, it also alters peripheral feedback to the CG. PMID:19946074

  15. Sex, Diet, and the Social Environment: Factors Influencing Hair Cortisol Concentration in Free-Ranging Black Bears (Ursus americanus)

    PubMed Central

    Lafferty, Diana J. R.; Laudenslager, Mark L.; Mowat, Garth; Heard, Doug; Belant, Jerrold L.

    2015-01-01

    Increasingly, measures of glucocorticoid levels (e.g., cortisol), key components of the neuroendocrine stress axis, are being used to measure past hypothalamic-pituitary-adrenal (HPA) activity to index psychological and physiological stress exhibited by wildlife for assessing individual and population-level well-being. However, many intrinsic and extrinsic factors affect HPA activity in animals. Using American black bears (Ursus americanus; n = 116) as an ecological model and hair cortisol concentration (HCC) as an integrative measure of past HPA activity, we evaluated the influence of diet, sex and the social environment on black bear HCC in a free-ranging population that spanned adjoining ecoregions with differing densities of potential conspecific and heterospecific competitors. HCC varied by sex, with female HCC ranging from 0.6 to 10.7 pg/mg (median = 4.5 ± 1.2 mean absolute deviation [MAD]) and male HCC ranging from 0.5 to 35.1 pg/mg (median = 6.2 ± 2.6 MAD). We also observed a three-way interaction among sex, δ14C and ecoregion, which may indicate that some differences in HCC between female and male black bears results from variability in the nutritional needs of larger-bodied males relative to smaller-bodied females, slight differences in food resources use between ecoregions as well as sex-based differences regarding the social environment. Once we understand what drives sex-specific differences in HCC, HCC may aid our understanding of the physiological responses by bears and other wildlife to diverse environmental challenges. PMID:26529405

  16. Post-Mating Interactions and Their Effects on Fitness of Female and Male Echinothrips americanus (Thysanoptera: Thripidae), a New Insect Pest in China

    PubMed Central

    Li, Xiao-Wei; Jiang, Hong-Xue; Zhang, Xiao-Chen; Shelton, Anthony M.; Feng, Ji-Nian

    2014-01-01

    Post-mating, sexual interactions of opposite sexes differ considerably in different organisms. Post-mating interactions such as re-mating behavior and male harassment can affect the fitness of both sexes. Echinothrips americanus is a new insect pest in Mainland China, and little is known about its post-mating interactions. In this study, we observed re-mating frequency and male harassment frequency and their effects on fitness parameters and offspring sex ratios of E. americanus females. Furthermore, we tested the impact of mating and post-mating interactions on fitness parameters of males. Our results revealed that the re-mating frequency in female adults was extremely low during a 30-day period. However, post-mating interactions between females and males, consisting mainly of male harassment and female resistance, did occur and significantly reduced female longevity and fecundity. Interestingly, increased access to males did not affect the ratio of female offspring. For males, mating dramatically reduced their longevity. However, post-mating interactions with females had no effects on the longevity of mated males. These results enrich our basic knowledge about female and male mating and post-mating behaviors in this species and provide important information about factors that may influence population regulation of this important pest species. PMID:24489956

  17. Bioindicators of contaminant exposure, liver pathology, and reproductive development in prespawning female winter flounder ('Pleuronectes americanus') from urban and nonurban estuaries on the northeast Atlantic coast. Technical memo

    SciTech Connect

    Johnson, L.L.; Stein, J.E.; Collier, T.K.; Casillas, E.; McCain, B.

    1992-08-01

    Relationships between liver pathology and ovarian development, and exposure to xenobiotic compounds were evaluated in prespawning female winter flounder (Pleuronectes americanus, formerly Pseudopleuronectes americanus) sampled from 11 sites on the Northeast coast of the United States during the 1988 and 1989 spawning seasons. Sediments from three sites exhibited a wide range in concentrations of xenobiotic compounds (e.g. concentrations of polycyclic aromatic hydrocarbons (PAHs) ranged from 20 to 50,000 ng/g dry weight and concentrations of polychlorinated biphenyls (PCBs) ranged from 2 to 1,400 ng/g dry weight), with the sites in Boston Harbor and Raritan Bay the most heavily contaminated. The following parameters associated with ovarian development were measured: ovarian developmental stage, ovarian atresia, gonadosomatic index, plasma estradiol, fecundity, and egg weight. Contaminant exposure was assessed by measuring concentrations of fluorescent aromatic compounds (FACs) in the bile; hepatic aryl hydrocarbon hydroxylase (AHH) activity; concentrations of polychlorinated biphenyls (PCBs) in liver, ovary, and brain; and levels of xenobiotic-DNA adducts in liver tissue. In general, indicators of contaminant exposure were elevated and prevalences of suspected toxicopathic lesions were highest in fish from sites within Boston Harbor and Raritan Bay.

  18. Genetic Characterization of Sarcoptes scabiei from Black Bears (Ursus americanus) and Other Hosts in Eastern United States.

    PubMed

    Peltier, Sarah; Brown, Justin D; Ternent, Mark; Niedringhaus, Kevin D; Schuler, Krysten; Bunting, Elizabeth; Kirchgessner, Megan; Yabsley, Michael John

    2017-06-22

    Since the early 1990s there has been an increase in the number of cases and geographic expansion of severe mange in the black bear (Ursus americanus) population in Pennsylvania. Although there are 3 species of mites associated with mange in bears, Sarcoptes scabiei has been identified as the etiologic agent in these Pennsylvania cases. Historically S. scabiei-associated mange in bears has been uncommon and sporadic although it is widespread and relatively common in canid populations. To better understand this recent emergence of sarcoptic mange in bears in Pennsylvania and nearby states, we genetically characterized S. scabiei samples from black bears in the Eastern United States. These sequences were compared to newly acquired S. scabiei sequences from wild canids [red fox (Vulpes vulpes) and coyote (Canis latrans)] and a porcupine (Erethizon dorsatum) from Pennsylvania and Kentucky and also existing sequences in GenBank. The internal transcribed spacer (ITS)-2 region and cytochrome c oxidase subunit 1 (cox1) gene were amplified and sequenced. Twenty-four ITS-2 sequences were obtained from mites from bears (n = 16), red fox (n = 5), coyote (n = 2), and a porcupine. The sequences from bear samples were identical to each other or differed only at polymorphic bases while S. scabiei from canids were more variable but two were identical to S. scabiei sequences from bears. Eighteen cox1 sequences obtained from mites from bears represented 6 novel haplotypes. Phylogenetic analysis of cox1 sequences revealed four clades: 2 clades of mites of human origin from Panama or Australia, a clade of mites from rabbits from China, and a large unresolved clade that included the remaining S. scabiei sequences from various hosts and regions, including sequences from the bears from the current study. Although the cox1 gene was more variable than the ITS-2, phylogenetic analyses failed to detect any clustering of S. scabiei from Eastern U.S. hosts. Rather sequences from black bears

  19. Isolation and characterization of new genetic types of Toxoplasma gondii and prevalence of Trichinella murrelli from black bear (Ursus americanus).

    PubMed

    Dubey, J P; Hill, D; Zarlenga, D; Choudhary, S; Ferreira, L R; Oliveira, S; Verma, S K; Kwok, O C H; Driscoll, C P; Spiker, H; Su, C

    2013-09-01

    Black bears (Ursus americanus) are hosts for two important zoonotic parasites, Toxoplasma gondii and Trichinella spp. and bears are hunted for human consumption in the USA. Little is known of the genetic diversity of T. gondii circulating in wildlife. In the present study, antibodies to T. gondii were found in juice from tongues of 17 (25.7%) of 66 wild black bear from Maryland during the hunting season of 2010 and 2011. Antibodies to T. gondii were assessed by the modified agglutination test. Tongues of 17 seropositive bears were bioassayed in mice and viable T. gondii was isolated from three samples. These three T. gondii isolates (TgBbMd1-3) were further propagated in cell culture and DNA isolated from culture-derived tachyzoites was characterized using 11 PCR-RFLP markers (SAG1, 5'- and 3'-SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico). Results revealed three genotypes. TgBbMd1 is a Type 12 strain (ToxoDB PCR-RFLP genotype #4) and TgBbMd2 is ToxoDB PCR-RFLP genotype #216, and TgBbMd3 is a Type II clonal strain (ToxoDB PCR-RFLP genotype #1). The isolate TgBbMd2 was highly virulent for outbred Swiss Webster mice; all infected mice died of acute toxoplasmosis. Results indicate that mouse virulent strains of T. gondii are circulating in wildlife in the USA. These 66 tongues in addition to tongues collected during hunts in previous years were further investigated for the presence of muscle larvae of Trichinella spp. Tongues from 40 bears in 2005, 41 in 2006, 51 in 2007, 56 in 2008, 68 in 2009, 67 in 2010, and 66 in 2011 were subjected to digestion with pepsin/HCl and microscopic examination. Two bears were infected with Trichinella spp.; one in 2008 and one in 2009. Genotyping of collected muscle larvae revealed that the infecting species in both cases was Trichinella murrelli. Published by Elsevier B.V.

  20. Windowpane flounder (Scophthalmus aquosus) and winter flounder (Pseudopleuronectes americanus) responses to cold temperature extremes in a Northwest Atlantic estuary

    NASA Astrophysics Data System (ADS)

    Wilber, Dara H.; Clarke, Douglas G.; Alcoba, Catherine M.; Gallo, Jenine

    2016-01-01

    The effect of climate variability on flatfish includes not only the effects of warming on sensitive life history stages, but also impacts from more frequent or unseasonal extreme cold temperatures. Cold weather events can affect the overwintering capabilities of flatfish near their low temperature range limits. We examined the responses of two flatfish species, the thin-bodied windowpane (Scophthalmus aquosus) and cold-tolerant winter flounder (Pseudopleuronectes americanus), to variable winter temperatures in a Northwest Atlantic estuary using abundance and size data collected during a monitoring study, the Aquatic Biological Survey, conducted from 2002 to 2010. Winter and spring abundances of small (50 to 120 mm total length) juvenile windowpane were positively correlated with adult densities (spawning stock) and fall temperatures (thermal conditions experienced during post-settlement development for the fall-spawned cohort) of the previous year. Windowpane abundances in the estuary were significantly reduced and the smallest size class was nearly absent after several consecutive years with cold (minimum temperatures < 1 °C) winters. Interannual variation in winter flounder abundances was unrelated to the severity of winter temperatures. A Paulik diagram illustrates strong positive correlations between annual abundances of sequential winter flounder life history stages (egg, larval, Age-1 juvenile, and adult male) within the estuary, reflecting residency within the estuary through their first year of life. Temperature variables representing conditions during winter flounder larval and post-settlement development were not significant factors in multiple regression models exploring factors that affect juvenile abundances. Likewise, densities of predators known to consume winter flounder eggs and/or post-settlement juveniles were not significantly related to interannual variation in winter flounder juvenile abundances. Colder estuarine temperatures through the

  1. Investigating the mechanism for maintaining eucalcemia despite immobility and anuria in the hibernating American black bear (Ursus americanus).

    PubMed

    Seger, Rita L; Cross, Randal A; Rosen, Clifford J; Causey, Robert C; Gundberg, Caren M; Carpenter, Thomas O; Chen, Tai C; Halteman, William A; Holick, Michael F; Jakubas, Walter J; Keisler, Duane H; Seger, Richard M; Servello, Frederick A

    2011-12-01

    Ursine hibernation uniquely combines prolonged skeletal unloading, anuria, pregnancy, lactation, protein recycling, and lipolysis. This study presents a radiographic and biochemical picture of bone metabolism in free-ranging, female American black bears (Ursus americanus) that were active (spring bears and autumn bears) or hibernating (hibernating bears). Hibernating bears included lactating and non-lactating individuals. We measured serum calcium, albumin, inorganic phosphate, creatinine, bone specific alkaline phosphatase (BSALP), CTX, parathyroid hormone, insulin-like growth factor-I (IGF-l), leptin, 25-hydroxyvitamin D [25(OH)D], 1,25-dihydroxyvitamin D [1,25(OH)(2)D] and sclerostin from 35 to 50 tranquilized hibernating bears and 14 to 35 tranquilized spring bears. We compared metacarpal cortical indices (MCI), measured by digital X-ray radiogrammetry, from 60 hunter-killed autumn bears and 79 tranquilized, hibernating bears. MCI was greater in autumn than winter in younger bears, but showed no seasonal difference in older bears. During hibernation eucalcemia was maintained, BSALP was suppressed, and CTX was in the range expected for anuria. During hibernation 1,25(OH)(2)D was produced despite anuria. 1,25(OH)(2)D and IGF-I were less in hibernating than spring bears. In a quarter of hibernating bears, sclerostin was elevated. Leptin was greater in hibernating than spring bears. In hibernating bears, leptin correlated positively with BSALP in non-lactating bears and with CTX in lactating bears. Taken together the biochemical and radiographic findings indicate that during hibernation, bone turnover was persistent, balanced, and suppressed; bone resorption was lower than expected for an unloaded skeleton; and there was no unloading-induced bone loss. The skeleton appears to perceive that it was loaded when it was actually unloaded during hibernation. However, at the level of sclerostin, the skeleton recognized that it was unloaded. During hibernation leptin

  2. Seroepidemiologic study on the prevalence of Toxoplasma gondii and Trichinella spp. infections in black bears (Ursus americanus) in Pennsylvania, USA.

    PubMed

    Dubey, Jitender P; Brown, Justin; Ternent, Mark; Verma, Shiv K; Hill, Dolores E; Cerqueira-Cézar, Camila K; Kwok, Oliver C H; Calero-Bernal, Rafael; Humphreys, Jan G

    2016-10-15

    The protozoan Toxoplasma gondii and the metazoan Trichinella spp. infect virtually all warm-blooded animals, including birds, humans, livestock, and marine mammals. Both parasitic infections can cause serious illness in human beings and can be acquired by ingesting under-cooked meat harboring infective stages. Approximately 3500 black bears (Ursus americanus) are legally-harvested each year in Pennsylvania, USA during the November hunting season. Among animals found infected with T. gondii, the prevalence of T. gondii is the highest among black bears in the USA; however, little is currently known of epidemiology of toxoplasmosis in this host species. Serum samples were collected during the winters of 2015 and 2016 from adult female bears and their nursing cubs or yearlings while they were still in their dens. Additionally, archived sera from bear samples collected throughout the year, including hunter-harvested bears in November and trapped bears in the summer, were serologically tested. Antibodies to T. gondii were assayed by the modified agglutination test (MAT, cut-off 1:25) and antibodies to Trichinella spp. were assayed using a commercial enzyme-linked immunosorbent assay (ELISA). Overall, T. gondii antibodies were found in 87.6% (206/235) of adults, and 44.1% (30/68) of yearlings. In March 2015/2016 sampling, antibodies to T. gondii were found in 94% (30/32) adult female bears while in their den. Antibodies were detected in 5% (3/66) of the nursing cubs in the dens of these sows. One positive cub had a MAT titer of 1:160 and two were positive at the 1:25 dilution but not at 1:50. The adult females of these cubs had MAT titers ranging from 1:400 to 1:3200. Antibodies to Trichinella spp. were found in 3% (6/181) of adults and 3.6% (1/28) of yearlings; these 7 bears were also seropositive for T. gondii. No antibodies to Trichinella spp. were detected in the sera of 44 nursing cubs tested. The finding of T. gondii antibodies in only 3 of 66 cubs, and higher

  3. Multi-scale habitat relationships of snowshoe hares (Lepus americanus) in the mixed conifer landscape of the Northern Rockies, USA: Cross-scale effects of horizontal cover with implications for forest management

    Treesearch

    Joseph D. Holbrook; John R. Squires; Lucretia E. Olson; Rick L. Lawrence; Shannon L. Savage

    2016-01-01

    Snowshoe hares (Lepus americanus) are an ecologically important herbivore because they modify vegetation through browsing and serve as a prey resource for multiple predators. We implemented a multiscale approach to characterize habitat relationships for snowshoe hares across the mixed conifer landscape of the northern Rocky Mountains, USA. Our objectives were to (1)...

  4. An enzymatically inactivated hemoglobinase from Necator americanus induces neutralizing antibodies against multiple hookworm species and protects dogs against heterologous hookworm infection

    PubMed Central

    Pearson, Mark S.; Bethony, Jeffrey M.; Pickering, Darren A.; de Oliveira, Luciana M.; Jariwala, Amar; Santiago, Helton; Miles, Aaron P.; Zhan, Bin; Jiang, Desheng; Ranjit, Najju; Mulvenna, Jason; Tribolet, Leon; Plieskatt, Jordan; Smith, Tracey; Bottazzi, Maria Elena; Jones, Kathryn; Keegan, Brian; Hotez, Peter J.; Loukas, Alex

    2009-01-01

    Hookworms digest hemoglobin from erythrocytes via a proteolytic cascade that begins with the aspartic protease, APR-1. Ac-APR-1 from the dog hookworm, Ancylostoma caninum, protects dogs against hookworm infection via antibodies that neutralize enzymatic activity and interrupt blood-feeding. Toward developing a human hookworm vaccine, we expressed both wild-type (Na-APR-1wt) and mutant (Na-APR-1mut—mutagenesis of the catalytic aspartic acids) forms of Na-APR-1 from the human hookworm, Necator americanus. Refolded Na-APR-1wt was catalytically active, and Na-APR-1mut was catalytically inactive but still bound substrates. Vaccination of canines with Na-APR-1mut and heterologous challenge with A. caninum resulted in significantly reduced parasite egg burdens (P=0.034) and weight loss (P=0.022). Vaccinated dogs also had less gut pathology, fewer adult worms, and reduced blood loss compared to controls but these did not reach statistical significance. Vaccination with Na-APR-1mut induced antibodies that bound the native enzyme in the parasite gut and neutralized enzymatic activity of Na-APR-1wt and APR-1 orthologues from three other hookworm species that infect humans. IgG1 against Na-APR-1mut was the most prominently detected antibody in sera from people resident in high-transmission areas for N. americanus, indicating that natural boosting may occur in exposed humans. Na-APR-1mut is now a lead antigen for the development of an antihematophagy vaccine for human hookworm disease.—Pearson, M. S., Bethony, J. M., Pickering, D. A., de Oliveira, L. M., Jariwala, A., Santiago, H., Miles, A. P., Zhan, B., Jiang, D., Ranjit, N., Mulvenna, J., Tribolet, L., Plieskatt, J., Smith, T., Bottazzi, M. E., Jones, K., Keegan, B., Hotez, P. J., Loukas, A. An enzymatically inactivated hemoglobinase from Necator americanus induces neutralizing antibodies against multiple hookworm species and protects dogs against heterologous hookworm infection. PMID:19380510

  5. Styrax americanus Lam.

    Treesearch

    K.F Connor

    2004-01-01

    American snowbell, also known as mock orange or storax, is a deciduous shrub or small tree with a widely branched crown. It reaches 3 to 5 m in height, and the stems can reach 7.5 cm in diameter. While the bark on the stems is smooth and dark grey to brown, branches range in color from green to grey to red-brown. Young stems are pubescent, becoming glabrous with age....

  6. Triplex polymerase chain reaction assay for detection of major soil-transmitted helminths, Ascaris lumbricoides, Trichuris trichiura, Necator americanus, in fecal samples.

    PubMed

    Phuphisut, Orawan; Yoonuan, Tippayarat; Sanguankiat, Surapol; Chaisiri, Kittipong; Maipanich, Wanna; Pubampen, Somchit; Komalamisra, Chalit; Adisakwattana, Poom

    2014-03-01

    Ascaris lumbricoides, Trichuris trichiura, and Necator americanus are medically important soil-transmitted helminths (STHs) occurring frequently worldwide including Thailand. Fecal examination using a microscope has been recommended as the gold standard for diagnosis of STH infections, but suffers from low sensitivity. Recently, highly sensitive and specific assays, such as multiplex quantitative PCR, has been established, but the high cost and need for special instruments are still barriers limiting their applications in routine diagnosis. Therefore, a conventional multiplex PCR assay, with its lower cost and greater simplicity, was developed, for the simultaneous detection of STHs in fecal samples. The multiplex PCR assay was species-specific to the three STHs, and could detect one copy of DNA target. Compared with microscopic examination of fecal samples, sensitivity and specificity of the multiplex PCR was 87% and 83%, respectively. This multiplex PCR assay provides an alternative method for routine diagnosis of STHs infection, and might be applied for epidemiological studies of STHs in endemic areas.

  7. Isolation and genetic characterization of Toxoplasma gondii from raccoons (Procyon lotor), cats (Felis domesticus), striped skunk (Mephitis mephitis), black bear (Ursus americanus), and cougar (Puma concolor) from Canada.

    PubMed

    Dubey, J P; Quirk, T; Pittt, J A; Sundar, N; Velmurugan, G V; Kwok, O C H; Leclair, D; Hill, R; Su, C

    2008-02-01

    Viable Toxoplasma gondii was isolated by bioassay in mice from tissues of 2 feral cats (Felis domesticus), 2 raccoons (Procyon lotor), a skunk (Mephitis mephitis) trapped in remote locations in Manitoba, Canada, and a black bear (Ursus americanus) from Kuujjuaq, northern Quebec, Canada. Genotyping of these T. gondii isolates using polymorphisms at 10 nuclear markers including SAGI, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and an apicoplast marker Apico revealed 4 genotypes. None of the isolates was clonal archetypal Types I, II, and III found in the United States. These results are in contrast with the Type II genotype that is widespread in domestic animals and humans throughout the United States and Europe. This is the first genotyping of T. gondii isolates from this part of North America.

  8. Detection of the mRNA encoding vitellogenesis inhibiting hormone in neurosecretory cells of the X-organ in Homarus americanus by in situ hybridization.

    PubMed

    Laverdure, A M; Breuzet, M; Soyez, D; Becker, J

    1992-09-01

    Vitellogenesis inhibiting hormone (VIH)-mRNA in secretory cells of the eyestalk of Homarus americanus was detected by nonradioactive in situ hybridization (ISH) using two digoxigenin-tailed oligonucleotide probes deduced from the peptide sequence. Two distinct clusters of positive cells were observed in the medulla terminalis ganglionic X-organ (MGTX). Only one of them gave a strong immunoreaction after incubation with a specific polyclonal anti-VIH serum and corresponded to the conventionally described VIH producing cells. The significance of the cells reacting positively in ISH but not in immunocytochemistry (ICC) is discussed. Northern blot analysis using 32P-labeling confirms the specificity of the probes and indicates an approximate size of 2.5 kb for VIH mRNA.

  9. Immunological relationships between neuropeptides from the sinus gland of the lobster Homarus americanus, with special references to the vitellogenesis inhibiting hormone and crustacean hyperglycemic hormone.

    PubMed

    Meusy, J J; Soyez, D

    1991-03-01

    Antisera raised in guinea pigs against four major neuropeptides purified from sinus glands of the lobster, Homarus americanus, were used to study the immunological relationships between several sinus gland peptides. On the basis of their behavior in ELISA and in absorption procedures, three groups of peptides are defined. Two groups may be related to the crustacean hyperglycemic hormone (CHH groups); the third one is composed of three immunologically identical peptides and, since one of these peptides was characterized in previous studies as a vitellogenesis inhibitor, is referred to as VIH group. This closely meets our present knowledge about the physiological effects and biochemical characteristics of these neuropeptides and gives immunological insights on the question of molecular polymorphism of lobster neurohormones.

  10. Identification of grouper (Epinephelus guaza), wreck fish (Polyprion americanus), and Nile perch (Lates niloticus) fillets by polyclonal antibody-based enzyme-linked immunosorbent assay.

    PubMed

    Asensio, Luis; González, Isabel; Rodríguez, Miguel A; Mayoral, Belén; López-Calleja, Inés; Hernández, Pablo E; García, Teresa; Martín, Rosario

    2003-02-26

    An indirect enzyme-linked immunosorbent assay (ELISA) has been developed for the species identification of grouper (Epinephelus guaza), wreck fish (Polyprion americanus), and Nile perch (Lates niloticus) fillets. The assay was performed in two different formats, microtiter plates and immunostick tubes, and uses polyclonal antibodies raised in rabbits against muscle-soluble proteins of grouper (anti-GSP), wreck fish (anti-WSP), and Nile perch (anti-PSP). The antibodies were made species-specific by blocking them with the heterologous soluble muscle proteins. Immunorecognition of polyclonal antibodies adsorbed to their specific fish samples was made with swine antirabbit immunoglobulins conjugated to the enzyme horseradish peroxidase. Subsequent enzymatic conversion of the substrate allowed unequivocal identification of the species studied.

  11. Taxonomy and host-specificity of Gyrodactylus aideni n. sp. and G. pleuronecti (Monogenea: Gyrodactylidae) from Pseudopleuronectes americanus (Walbaum) in Passamaquoddy Bay, New Brunswick, Canada.

    PubMed

    Mullen, A J; Cone, D K; Easy, R; Burt, M D B

    2010-11-01

    Wild and cultured winter flounder Pseudopleuronectes americanus (Walbaum) from Passamaquoddy Bay were surveyed for species of Gyrodactylus Nordmann, 1832. Two species were found: G. pleuronecti Cone, 1981 and G. aideni n. sp, both members of Malmberg's 'groenlandicus group'. Although the hard parts in the haptor are very similar in the two species, hamuli of G. aideni are consistently shorter than those of G. pleuronecti. The two species differed by 35 base pairs in the ITS 1, 5.8 and ITS 2 region. A BLAST search identified a variety of species of Gyrodactylus from marine fishes in the Atlantic Ocean as closest matches, indicating the 'groenlandicus group' is part of a major marine lineage within Gyrodactylus (sensu lato) that has successfully radiated among coastal percid, pleuronectid, cottid and anarhichadid fishes. Exposure experiments suggested that winter flounder is the primary host of both species of parasites and that three other pleuronectid species in the bay may potentially serve only as occasional transport hosts.

  12. Diversity in the structures and ligand-binding sites of nematode fatty acid and retinol-binding proteins revealed by Na-FAR-1 from Necator americanus

    PubMed Central

    Rey-Burusco, M. Florencia; Ibáñez-Shimabukuro, Marina; Gabrielsen, Mads; Franchini, Gisela R.; Roe, Andrew J.; Griffiths, Kate; Zhan, Bin; Cooper, Alan; Kennedy, Malcolm W.; Córsico, Betina; Smith, Brian O.

    2015-01-01

    Fatty acid and retinol-binding proteins (FARs) comprise a family of unusual α-helix rich lipid-binding proteins found exclusively in nematodes. They are secreted into host tissues by parasites of plants, animals and humans. The structure of a FAR protein from the free-living nematode Caenorhabditis elegans is available, but this protein [C. elegans FAR-7 (Ce-FAR-7)] is from a subfamily of FARs that does not appear to be important at the host/parasite interface. We have therefore examined [Necator americanus FAR-1 (Na-FAR-1)] from the blood-feeding intestinal parasite of humans, N. americanus. The 3D structure of Na-FAR-1 in its ligand-free and ligand-bound forms, determined by NMR (nuclear magnetic resonance) spectroscopy and X-ray crystallography respectively, reveals an α-helical fold similar to Ce-FAR-7, but Na-FAR-1 possesses a larger and more complex internal ligand-binding cavity and an additional C-terminal α-helix. Titration of apo-Na-FAR-1 with oleic acid, analysed by NMR chemical shift perturbation, reveals that at least four distinct protein–ligand complexes can be formed. Na-FAR-1 and possibly other FARs may have a wider repertoire for hydrophobic ligand binding, as confirmed in the present study by our finding that a range of neutral and polar lipids co-purify with the bacterially expressed recombinant protein. Finally, we show by immunohistochemistry that Na-FAR-1 is present in adult worms with a tissue distribution indicative of possible roles in nutrient acquisition by the parasite and in reproduction in the male. PMID:26318523

  13. Sequence conservation in the Ancylostoma secreted protein-2 of Necator americanus (Na-ASP-2) from hookworm infected individuals in Thailand.

    PubMed

    Ungcharoensuk, Charoenchai; Putaporntip, Chaturong; Pattanawong, Urassaya; Jongwutiwes, Somchai

    2012-12-01

    The Ancylostoma secreted protein-2 of Necator americanus (Na-ASP-2) was one of the promising vaccine candidates against the most prevalent human hookworm species as adverse vaccine reaction has compromised further human vaccine trials. To elucidate the gene structure and the extent of sequence diversity, we determined the complete nucleotide sequence of the Na-asp-2 gene of individual larvae from 32 infected subjects living in 3 different endemic areas of Thailand. Sequence analysis revealed that the gene encoding Na-ASP-2 comprised 8 exons. Of 3 nucleotide substitutions in these exons, only one causes an amino acid change from leucine to methionine. A consensus conserved GT and AG at the 5' and the 3' boundaries of each intron was observed akin to those found in other eukaryotic genes. Introns of Na-asp-2 contained 23 nucleotide substitutions and 0-18 indels. The mean number of nucleotide substitutions per site (d) in introns was not significantly different from the mean number of synonymous substitutions per synonymous site (d(S)) in exons whereas d in introns was significantly exceeded d(N) (the mean number of nonsynonymous substitutions per nonsynonymous site) in exons (p<0.05), suggesting that introns and synonymous sites in exons may evolve at a similar rate whereas functional constraints at the amino acid could limit amino acid substitutions in Na-ASP-2. A recombination site was identified in an intron near the 3' portion of the gene. The positions of introns and the intron phases in the Na-asp-2 gene comparing with those in other pathogenesis-related-1 proteins of Loa loa, Onchocerca volvulus, Heterodera glycines, Caenorhabditis elegans and human were relatively conserved, suggesting evolutionary conservation of these genes. Sequence conservation in Na-ASP-2 may not compromise further vaccine design if adverse vaccine effects could be resolved whereas microheterogeneity in introns of this locus may be useful for population genetics analysis of N. americanus.

  14. Identification of a calcitonin-like diuretic hormone that functions as an intrinsic modulator of the American lobster, Homarus americanus, cardiac neuromuscular system

    PubMed Central

    Christie, A. E.; Stevens, J. S.; Bowers, M. R.; Chapline, M. C.; Jensen, D. A.; Schegg, K. M.; Goldwaser, J.; Kwiatkowski, M. A.; Pleasant, T. K.; Shoenfeld, L.; Tempest, L. K.; Williams, C. R.; Wiwatpanit, T.; Smith, C. M.; Beale, K. M.; Towle, D. W.; Schooley, D. A.; Dickinson, P. S.

    2010-01-01

    In insects, a family of peptides with sequence homology to the vertebrate calcitonins has been implicated in the control of diuresis, a process that includes mixing of the hemolymph. Here, we show that a member of the insect calcitonin-like diuretic hormone (CLDH) family is present in the American lobster, Homarus americanus, serving, at least in part, as a powerful modulator of cardiac output. Specifically, during an ongoing EST project, a transcript encoding a putative H. americanus CLDH precursor was identified; a full-length cDNA was subsequently cloned. In silico analyses of the deduced prepro-hormone predicted the mature structure of the encoded CLDH to be GLDLGLGRGFSGSQAAKHLMGLAAANFAGGPamide (Homam-CLDH), which is identical to a known Tribolium castaneum peptide. RT-PCR tissue profiling suggests that Homam-CLDH is broadly distributed within the lobster nervous system, including the cardiac ganglion (CG), which controls the movement of the neurogenic heart. RT-PCR analysis conducted on pacemaker neuron- and motor neuron-specific cDNAs suggests that the motor neurons are the source of the CLDH message in the CG. Perfusion of Homam-CLDH through the isolated lobster heart produced dose-dependent increases in both contraction frequency and amplitude and a dose-dependent decrease in contraction duration, with threshold concentrations for all parameters in the range 10–11 to 10–10 mol l–1 or less, among the lowest for any peptide on this system. This report is the first documentation of a decapod CLDH, the first demonstration of CLDH bioactivity outside the Insecta, and the first detection of an intrinsic neuropeptide transcript in the crustacean CG. PMID:20008368

  15. Crystallization and preliminary X-ray analysis of Na-ASP-1, a multi-domain pathogenesis-related-1 protein from the human hookworm parasite Necator americanus

    SciTech Connect

    Asojo, Oluwatoyin A.; Loukas, Alex; Inan, Mehmet; Barent, Rick; Huang, Jicai; Plantz, Brad; Swanson, Amber; Gouthro, Mark; Meagher, Michael M.; Hotez, Peter J.

    2005-04-01

    In order to clarify the structural basis of the pathogenesis-related-1 domain, Na-ASP-1, the first multi-domain ASP from the human hookworm parasite N. americanus, has been crystallized. 2.2 Å resolution data have been collected from a crystal belonging to the monoclinic space group P2{sub 1}. Human hookworm infection is a major cause of anemia and malnutrition in the developing world. In an effort to control hookworm infection, the Human Hookworm Vaccine Initiative has identified candidate vaccine antigens from the infective larval stage (L3) of the parasite, including a family of pathogenesis-related-1 (PR-1) proteins known as the ancylostoma-secreted proteins (ASPs). The functions of the ASPs are unknown. In addition, it is unclear why some ASPs have one while others have multiple PR-1 domains. There are no known structures of a multi-domain ASP and in an effort to remedy this situation, recombinant Na-ASP-1 has been expressed, purified and crystallized. Na-ASP-1 is a 406-amino-acid multi-domain ASP from the prevalent human hookworm parasite Necator americanus. Useful X-ray data to 2.2 Å have been collected from a crystal that belongs to the monoclinic space group P2{sub 1} with unit-cell parameters a = 67.7, b = 74.27, c = 84.60 Å, β = 112.12°. An initial molecular-replacement solution has been obtained with one monomer in the asymmetric unit.

  16. An enzymatically inactivated hemoglobinase from Necator americanus induces neutralizing antibodies against multiple hookworm species and protects dogs against heterologous hookworm infection.

    PubMed

    Pearson, Mark S; Bethony, Jeffrey M; Pickering, Darren A; de Oliveira, Luciana M; Jariwala, Amar; Santiago, Helton; Miles, Aaron P; Zhan, Bin; Jiang, Desheng; Ranjit, Najju; Mulvenna, Jason; Tribolet, Leon; Plieskatt, Jordan; Smith, Tracey; Bottazzi, Maria Elena; Jones, Kathryn; Keegan, Brian; Hotez, Peter J; Loukas, Alex

    2009-09-01

    Hookworms digest hemoglobin from erythrocytes via a proteolytic cascade that begins with the aspartic protease, APR-1. Ac-APR-1 from the dog hookworm, Ancylostoma caninum, protects dogs against hookworm infection via antibodies that neutralize enzymatic activity and interrupt blood-feeding. Toward developing a human hookworm vaccine, we expressed both wild-type (Na-APR-1(wt)) and mutant (Na-APR-1(mut)-mutagenesis of the catalytic aspartic acids) forms of Na-APR-1 from the human hookworm, Necator americanus. Refolded Na-APR-1(wt) was catalytically active, and Na-APR-1(mut) was catalytically inactive but still bound substrates. Vaccination of canines with Na-APR-1(mut) and heterologous challenge with A. caninum resulted in significantly reduced parasite egg burdens (P=0.034) and weight loss (P=0.022). Vaccinated dogs also had less gut pathology, fewer adult worms, and reduced blood loss compared to controls but these did not reach statistical significance. Vaccination with Na-APR-1(mut) induced antibodies that bound the native enzyme in the parasite gut and neutralized enzymatic activity of Na-APR-1(wt) and APR-1 orthologues from three other hookworm species that infect humans. IgG1 against Na-APR-1(mut) was the most prominently detected antibody in sera from people resident in high-transmission areas for N. americanus, indicating that natural boosting may occur in exposed humans. Na-APR-1(mut) is now a lead antigen for the development of an antihematophagy vaccine for human hookworm disease.

  17. Identification of a calcitonin-like diuretic hormone that functions as an intrinsic modulator of the American lobster, Homarus americanus, cardiac neuromuscular system.

    PubMed

    Christie, A E; Stevens, J S; Bowers, M R; Chapline, M C; Jensen, D A; Schegg, K M; Goldwaser, J; Kwiatkowski, M A; Pleasant, T K; Shoenfeld, L; Tempest, L K; Williams, C R; Wiwatpanit, T; Smith, C M; Beale, K M; Towle, D W; Schooley, D A; Dickinson, P S

    2010-01-01

    In insects, a family of peptides with sequence homology to the vertebrate calcitonins has been implicated in the control of diuresis, a process that includes mixing of the hemolymph. Here, we show that a member of the insect calcitonin-like diuretic hormone (CLDH) family is present in the American lobster, Homarus americanus, serving, at least in part, as a powerful modulator of cardiac output. Specifically, during an ongoing EST project, a transcript encoding a putative H. americanus CLDH precursor was identified; a full-length cDNA was subsequently cloned. In silico analyses of the deduced prepro-hormone predicted the mature structure of the encoded CLDH to be GLDLGLGRGFSGSQAAKHLMGLAAANFAGGPamide (Homam-CLDH), which is identical to a known Tribolium castaneum peptide. RT-PCR tissue profiling suggests that Homam-CLDH is broadly distributed within the lobster nervous system, including the cardiac ganglion (CG), which controls the movement of the neurogenic heart. RT-PCR analysis conducted on pacemaker neuron- and motor neuron-specific cDNAs suggests that the motor neurons are the source of the CLDH message in the CG. Perfusion of Homam-CLDH through the isolated lobster heart produced dose-dependent increases in both contraction frequency and amplitude and a dose-dependent decrease in contraction duration, with threshold concentrations for all parameters in the range 10(-11) to 10(-10) mol l(-1) or less, among the lowest for any peptide on this system. This report is the first documentation of a decapod CLDH, the first demonstration of CLDH bioactivity outside the Insecta, and the first detection of an intrinsic neuropeptide transcript in the crustacean CG.

  18. Ulcerative enteritis in Homarus americanus: case report and molecular characterization of intestinal aerobic bacteria of apparently healthy lobsters in live storage.

    PubMed

    Battison, Andrea L; Després, Béatrice M; Greenwood, Spencer J

    2008-10-01

    An intermoult male American lobster, Homarus americanus, with severe intestinal lesions was encountered while collecting samples of aerobic intestinal bacteria from lobsters held in an artificial sea-water recirculation aquarium system. Grossly, the intestine was firm, thickened, and white. Histologic examination revealed a severe, diffuse, ulcerative enteritis which spared the chitin-lined colon, somewhat similar to hemocytic enteritis of shrimp. The bacterial isolates from this lobster were compared to 11 other lobsters lacking gross intestinal lesions. Two organisms, one identified as Vibrio sp. and another most similar to an uncultured proteobacterium (98.9%), clustering with Rhanella and Serratia species using 16S rDNA PCR, were isolated from the intestines of the 11, grossly normal, lobsters and the affected lobster. An additional two intestinal isolates were cultured only from the lobster with ulcerative enteritis. One, a Flavobacterium, similar to Lutibacter litoralis (99.3%), possibly represented a previously described commensal of the distal intestine. The second, a Vibrio sp., was unique to the affected animal. While the etiology of the ulcerative enteritis remains undetermined, this report represents the first description of gross and histologic findings in H. americanus of a condition which has morphologic similarities to hemocytic enteritis of shrimp. An additional observation was a decrease in the number of intestinal isolates recovered from the 11 apparently healthy lobsters compared to that previously reported for recently harvested lobster. More comprehensive studies of the relationship between the health of lobsters, gut microbial flora and the husbandry and environment maintained within holding units are warranted.

  19. Optimization and revision of the production process of the Necator americanus glutathione S-transferase 1 (Na-GST-1), the lead hookworm vaccine recombinant protein candidate.

    PubMed

    Curti, Elena; Seid, Christopher A; Hudspeth, Elissa; Center, Lori; Rezende, Wanderson; Pollet, Jeroen; Kwityn, Cliff; Hammond, Molly; Matsunami, Rise K; Engler, David A; Hotez, Peter J; Elena Bottazzi, Maria

    2014-01-01

    Infection by the human hookworm Necator americanus is a leading cause of anemia and disability in the developing countries of Africa, Asia, and the Americas. In order to prevent childhood hookworm disease in resource poor settings, a recombinant vaccine is under development by the Sabin Vaccine Institute and Texas Children's Hospital Center for Vaccine Development, a Product Development Partnership (PDP). Previously, we reported on the expression and purification of a highly promising hookworm vaccine candidate, Na-GST-1, an N. americanus glutathione s-transferase expressed in Pichia pastoris (yeast), which led to production of 1.5 g of 95% pure recombinant protein at a 20L scale. (1) (,) (2) (,) (3) This yield and purity of Na-GST-1 was sufficient for early pilot manufacturing and initial phase 1 clinical testing. However, based on the number of doses which would be required to allow mass vaccination and a potential goal to deliver a vaccine as inexpensively as possible, a higher yield of expression of the recombinant antigen at the lowest possible cost is highly desirable. Here we report on modifications to the fermentation (upstream process) of the antigen expressed in P. pastoris, and to the purification (downstream process) of the recombinant protein that allowed for a 2-3-fold improvement in the final yield of Na-GST-1 purified protein. The major improvements included upstream process changes such as the addition of a sorbitol pulse and co-feed during methanol induction as well as an extension of the induction stage to approximately 96 hours; downstream process changes included modifying the UFDF to flat sheet with a 10 kDa Molecular Weight cut-off (MWCO), adjusting the capacity of an ion-exchange chromatography step utilizing a gradient elution as opposed to the original step elution, and altering the hydrophobic interaction chromatography conditions. The full process, as well as the purity and stability profiles of the target Na-GST-1, and its formulation

  20. A comparison of human chorionic gonadotropin and luteinizing hormone releasing hormone on the induction of spermiation and amplexus in the American toad (Anaxyrus americanus)

    PubMed Central

    2012-01-01

    Background Captive breeding programs for endangered amphibian species often utilize exogenous hormones for species that are difficult to breed. The purpose of our study was to compare the efficacy of two different hormones at various concentrations on sperm production, quantity and quality over time in order to optimize assisted breeding. Methods Male American toads (Anaxyrus americanus) were divided into three separate treatment groups, with animals in each group rotated through different concentrations of luteinizing hormone releasing hormone analog (LHRH; 0.1, 1.0, 4.0 and 32 micrograms/toad), human chorionic gonadotropin (hCG; 50, 100, 200, and 300 IU), or the control over 24 hours. We evaluated the number of males that respond by producing spermic urine, the sperm concentration, percent motility, and quality of forward progression. We also evaluated the effects of hCG and LHRH on reproductive behavior as assessed by amplexus. Data were analyzed using the Generalized Estimating Equations incorporating repeated measures over time and including the main effects of treatment and time, and the treatment by time interaction. Results The hormone hCG was significantly more effective at stimulating spermiation in male Anaxyrus americanus than LHRH and showed a dose-dependent response in the number of animals producing sperm. At the most effective hCG dose (300 IU), 100% of the male toads produced sperm, compared to only 35% for the best LHRH dose tested (4.0 micrograms). In addition to having a greater number of responders (P < 0.05), the 300 IU hCG treatment group had a much higher average sperm concentration (P < 0.05) than the treatment group receiving 4.0 micrograms LHRH. In contrast, these two treatments did not result in significant differences in sperm motility or quality of forward progressive motility. However, more males went into amplexus when treated with LHRH vs. hCG (90% vs. 75%) by nine hours post-administration. Conclusion There is a clear

  1. Optimization and revision of the production process of the Necator americanus glutathione S-transferase 1 (Na-GST-1), the lead hookworm vaccine recombinant protein candidate

    PubMed Central

    Curti, Elena; Seid, Christopher A; Hudspeth, Elissa; Center, Lori; Rezende, Wanderson; Pollet, Jeroen; Kwityn, Cliff; Hammond, Molly; Matsunami, Rise K; Engler, David A; Hotez, Peter J; Elena Bottazzi, Maria

    2014-01-01

    Infection by the human hookworm Necator americanus is a leading cause of anemia and disability in the developing countries of Africa, Asia, and the Americas. In order to prevent childhood hookworm disease in resource poor settings, a recombinant vaccine is under development by the Sabin Vaccine Institute and Texas Children’s Hospital Center for Vaccine Development, a Product Development Partnership (PDP). Previously, we reported on the expression and purification of a highly promising hookworm vaccine candidate, Na-GST-1, an N. americanus glutathione s-transferase expressed in Pichia pastoris (yeast), which led to production of 1.5 g of 95% pure recombinant protein at a 20L scale.1, 2, 3 This yield and purity of Na-GST-1 was sufficient for early pilot manufacturing and initial phase 1 clinical testing. However, based on the number of doses which would be required to allow mass vaccination and a potential goal to deliver a vaccine as inexpensively as possible, a higher yield of expression of the recombinant antigen at the lowest possible cost is highly desirable. Here we report on modifications to the fermentation (upstream process) of the antigen expressed in P. pastoris, and to the purification (downstream process) of the recombinant protein that allowed for a 2–3-fold improvement in the final yield of Na-GST-1 purified protein. The major improvements included upstream process changes such as the addition of a sorbitol pulse and co-feed during methanol induction as well as an extension of the induction stage to approximately 96 hours; downstream process changes included modifying the UFDF to flat sheet with a 10 kDa Molecular Weight cut-off (MWCO), adjusting the capacity of an ion-exchange chromatography step utilizing a gradient elution as opposed to the original step elution, and altering the hydrophobic interaction chromatography conditions. The full process, as well as the purity and stability profiles of the target Na-GST-1, and its formulation on

  2. Structure of glutathione S-transferase 1 from the major human hookworm parasite Necator americanus (Na-GST-1) in complex with glutathione.

    PubMed

    Asojo, Oluwatoyin A; Ceccarelli, Christopher

    2014-09-01

    Glutathione S-transferase 1 from Necator americanus (Na-GST-1) is a vaccine candidate for hookworm infection that has a high affinity for heme and metal porphyrins. As part of attempts to clarify the mechanism of heme detoxification by hookworm GSTs, co-crystallization and soaking studies of Na-GST-1 with the heme-like molecules protoporphyrin IX disodium salt, hematin and zinc protoporphyrin were undertaken. While these studies did not yield the structure of the complex of Na-GST-1 with any of these molecules, co-crystallization experiments resulted in the first structures of the complex of Na-GST-1 with the substrate glutathione. The structures of the complex of Na-GST-1 with glutathione were solved from pathological crystalline aggregates comprising more than one crystal form. These first structures of the complex of Na-GST-1 with the substrate glutathione were solved by molecular replacement from data collected with a sealed-tube home source using the previously reported apo structure as the search model.

  3. Application of large-scale parentage analysis for investigating natal dispersal in highly vagile vertebrates: a case study of American black bears (Ursus americanus).

    PubMed

    Moore, Jennifer A; Draheim, Hope M; Etter, Dwayne; Winterstein, Scott; Scribner, Kim T

    2014-01-01

    Understanding the factors that affect dispersal is a fundamental question in ecology and conservation biology, particularly as populations are faced with increasing anthropogenic impacts. Here we collected georeferenced genetic samples (n = 2,540) from three generations of black bears (Ursus americanus) harvested in a large (47,739 km2), geographically isolated population and used parentage analysis to identify mother-offspring dyads (n = 337). We quantified the effects of sex, age, habitat type and suitability, and local harvest density at the natal and settlement sites on the probability of natal dispersal, and on dispersal distances. Dispersal was male-biased (76% of males dispersed) but a small proportion (21%) of females also dispersed, and female dispersal distances (mean ± SE  =  48.9±7.7 km) were comparable to male dispersal distances (59.0±3.2 km). Dispersal probabilities and dispersal distances were greatest for bears in areas with high habitat suitability and low harvest density. The inverse relationship between dispersal and harvest density in black bears suggests that 1) intensive harvest promotes restricted dispersal, or 2) high black bear population density decreases the propensity to disperse. Multigenerational genetic data collected over large landscape scales can be a powerful means of characterizing dispersal patterns and causal associations with demographic and landscape features in wild populations of elusive and wide-ranging species.

  4. Black bear (Ursus americanus Pallas) feeding damage across timber harvest edges in northern California coast redwood (Sequoia sempervirens[D. Don] Endl.) forests, USA

    USGS Publications Warehouse

    Russell, W.H.; Carnell, K.; McBride, J.R.

    2001-01-01

    Feeding damage to trees by black bears (Ursus americanus Pallas) was recorded in proximity to timber harvest edges in harvested and old-growth stands of coast redwood (Sequoia sempervirens [D. Don] Endl.) in northern California, USA. Bears exhibited distinct preference in their feeding patterns related to stand structure and composition and to distance from the timber-harvest edge. Most damage was recorded within regenerating stands. Regression analysis indicated that density of damaged trees was negatively correlated with distance from timber harvest edges within old-growth stands. A significant negative correlation was also found between the density of trees damaged by bears and habitat diversity (H') as measured by the Shannon diversity index. In addition, bears exhibited preference for pole-size trees (dbh = 10-50 cm) over all other size classes, and coast redwood over other species. In general, damage by bears appeared to act as a natural thinning agent in even-aged stands. No damage was recorded in old-growth stands except in close proximity to the timber-harvest edge where subcanopy recruitment was high.

  5. Necator americanus: The Na-ASP-2 protein secreted by the infective larvae induces neutrophil recruitment in vivo and in vitro

    PubMed Central

    Bower, Molly A.; Constant, Stephanie L.; Mendez, Susana

    2008-01-01

    The L3-secreted Ancylostoma Secreted Protein-2 from the human hookworm Necator americanus (Na-ASP-2) has been selected as a candidate vaccine antigen in anticipation of clinical trials. Its crystal structure revealed that Na-ASP-2 has structural and charge similarities to CC-chemokines, suggesting that it might act as a chemokine mimic when released by the infective larvae during tissue migration. Using the air pouch model of acute inflammation, we found that Na-ASP-2 induced a significant leukocyte influx to the skin pouch, mostly comprised of neutrophils (60%) and monocytes (30%) that was transient and resolved in 24 h. Other hookworm larval proteins did not cause any inflammatory leukocytes to migrate into air pouches. In vitro chemotaxis assays confirmed our results and demonstrated that leukocyte migration was a direct effect of Na-ASP-2 exposure and not caused by other molecules released by host cells in the inflammatory microenvironment or by the expression vector. PMID:18199436

  6. White-tailed deer (Odocoileus virginianus) subsidize gray wolves (Canis lupus) during a moose (Alces americanus) decline: A case of apparent competition?

    USGS Publications Warehouse

    Barber-Meyer, Shannon; Mech, L. David

    2016-01-01

    Moose (Alces americanus) in northeastern Minnesota have declined by 55% since 2006. Although the cause is unresolved, some studies have suggested that Gray Wolves (Canis lupus) contributed to the decline. After the Moose decline, wolves could either decline or switch prey. To determine which occurred in our study area, we compared winter wolf counts and summer diet before and after the Moose decline. While wolf numbers in our study area nearly doubled from 23 in winter 2002 to an average of 41 during winters 2011–2013, calf:cow ratios (the number of calves per cow observed during winter surveys) in the wider Moose range more than halved from 0.93 in 2002 to an average of 0.31 during 2011–2013. Compared to summer 2002, wolves in summers 2011–2013 consumed fewer Moose and more White-tailed Deer (Odocoileus virginianus). While deer densities were similar during each period, average vulnerability, as reflected by winter severity, was greater during 2011–2013 than 2002, probably explaining the wolf increase. During the wolf increase Moose calves remained a summer food item. These findings suggest that in part of the Moose range, deer subsidized wolf numbers while wolves also preyed on Moose calves. This contributed to a Moose decline and is a possible case of apparent competition and inverse-density-dependent predation.

  7. Molecular phylogeny and SNP variation of polar bears (Ursus maritimus), brown bears (U. arctos), and black bears (U. americanus) derived from genome sequences.

    PubMed

    Cronin, Matthew A; Rincon, Gonzalo; Meredith, Robert W; MacNeil, Michael D; Islas-Trejo, Alma; Cánovas, Angela; Medrano, Juan F

    2014-01-01

    We assessed the relationships of polar bears (Ursus maritimus), brown bears (U. arctos), and black bears (U. americanus) with high throughput genomic sequencing data with an average coverage of 25× for each species. A total of 1.4 billion 100-bp paired-end reads were assembled using the polar bear and annotated giant panda (Ailuropoda melanoleuca) genome sequences as references. We identified 13.8 million single nucleotide polymorphisms (SNP) in the 3 species aligned to the polar bear genome. These data indicate that polar bears and brown bears share more SNP with each other than either does with black bears. Concatenation and coalescence-based analysis of consensus sequences of approximately 1 million base pairs of ultraconserved elements in the nuclear genome resulted in a phylogeny with black bears as the sister group to brown and polar bears, and all brown bears are in a separate clade from polar bears. Genotypes for 162 SNP loci of 336 bears from Alaska and Montana showed that the species are genetically differentiated and there is geographic population structure of brown and black bears but not polar bears.

  8. The effect of soil composition and hydration on the bioavailability and toxicity of cadmium to hibernating juvenile American toads (Bufo americanus)

    USGS Publications Warehouse

    James, Stacy M.; Little, Edward E.; Semlitsch, Raymond D.

    2004-01-01

    The soil ecotoxicology literature has focused primarily on a few major taxa, to the neglect of other fossorial organisms such as amphibians. We selected cadmium (Cd) and the American toad (Bufo americanus) as a model contaminant and biological species to assess the impact of soil contamination on amphibian hibernation survival and post-hibernation condition. Soil sand composition (50, 70, 90%) and hydration (100, 150% water holding capacity (WHC)) were manipulated in addition to Cd concentration (0, 56, 165, 483 μg/g) to determine whether these soil properties affect toxicity. Soil Cd concentration significantly reduced survival and locomotor performance, and was correlated negatively with percent mass loss and positively with whole body Cd concentration. Higher sand content resulted in less mass loss and greater Cd uptake. Toads that were hibernated in 50% sand hydrated to 100% WHC had higher survival, less mass loss, and better sprint performance than those hibernated in 50% sand, 150% WHC. This study demonstrates that concentrations of Cd found in soil at highly contaminated sites can be bioaccumulated by hibernating amphibians and may reduce fitness. Differences in microhabitat use may cause species to vary in their exposure and susceptibility to soil contamination. The toxicity of Cd to amphibians could be greater in natural systems where there are multiple stressors and fluctuations in environmental variables.

  9. Effects of molting and environmental factors on trace metal body-burdens and hemocyanin concentrations in the American lobster, Homarus americanus.

    PubMed

    Engel, D W; Brouwer, M; Mercaldo-Allen, R

    2001-09-01

    Hemocyanin concentrations in the hemolymph of marine crustacea are dependent on the molt cycle and on environmental conditions. Studies in our laboratories have found that hemocyanin levels in blue crabs are reduced after ecdysis and under conditions of environmental stress (Engel, Brouwer, & McKenna, 1993. Hemocyanin concentrations in marine crustaceans as a function of environmental conditions. Marine Ecology Progress Series, 93, 233-244). We have extended those studies to include the American lobster, Homarus americanus. Hemolymph and digestive gland tissues from Long Island Sound lobsters were analyzed for hemocyanin, copper, and zinc during different stages of the molt cycle. Hemocyanin, copper and zinc in the hemolymph were highest in premolt stages (D1-D4), and lowest in the postecdysal papershell stages (B1-B2). Concomitantly, copper in digestive glands decreased significantly following ecdysis, but no significant changes in the metals bound to metallothionein (MT) were observed. Copper-MT was the predominant form throughout the molt cycle, presumably because lobsters were obtained from copper-contaminated areas. To examine the effects of environmental factors, intermolt lobsters were collected from locations of different environmental quality along the Atlantic coast, and were analyzed for hemocyanin and trace metals. In general, animals from areas with a history of contamination showed the highest hemocyanin concentrations.

  10. Comparative reproductive success of winter flounder in Long Island Sound: A three-year study (biology, biochemistry, and chemistry). [Pseudopleuronectes americanus

    SciTech Connect

    Nelson, D.A.; Miller, J.E.; Rusanowsky, D.; Greig, R.A.; Sennefelder, G.R.; Mercaldo-Allen, R.; Kuropat, C.; Gould, E.; Thurberg, F.P.; Calabrese, A. )

    1991-09-01

    In a 3-yr study, late prespawning winter flounder (Pseudopleuronectes americanus) were collected from various stations in Long Island Sound (three of them heavily urbanized) and spawned in the laboratory. For comparative purposes, flounder from two sites in the Boston Harbor area were similarly treated in 1987 and 1988. Of the stations in Long Island Sound, New Haven Harbor alone consistently produced low percent viable hatch and small larvae. Boston Harbor produced the smallest larvae of all sites. There were no significant station-to-station differences in lipid utilization during larval development; yolk reserves at stations showing a low percent viable hatch, small larvae, and low embryonic development rate were probably used in part for stress metabolism. No significant differences in concentrations of polychlorinated biphenyls for collections from Long Island Sound were found either in livers of spawned fish, in sediments, or in eggs of winter flounder. The very low metal concentrations in winter flounder eggs showed no relation to the degree of metal contamination found at stations in Long Island Sound and Boston Harbor.

  11. Erythrocyte micronuclei in winter flounder (Pseudopleuronectes americanus): results of field surveys during 1980-1988 from Virginia to Nova Scotia and in Long Island Sound.

    PubMed

    Hughes, J B; Hebert, A T

    1991-05-01

    Erythrocyte micronuclei (MN) frequencies of 280 winter flounder (Pseudopleuronectes americanus) from Chesapeake Bay to the southern Scotian Shelf including Long Island Sound were measured. The MN data were combined with data previously reported for 224 flounder and the combined data sets were analyzed. Incidences of MN were elevated sixfold in flounder from the New York Bight Apex as compared to frequencies for fish from the inshore Gulf of Maine and Block Island Sound, and twice those found in Georges Bank and Long Island Sound flounder. Inshore New Jersey fish had higher MN frequencies than those from inshore Gulf Of Maine and Block Island Sound. The occurrence of MN in flounder from inshore Virginia was higher than in flounder from inshore Gulf of Maine and Block Island Sound. The large subset of stations from Long Island Sound indicated higher frequencies of MN in flounder from Hempstead and Shoreham as compared to most other sites in the Sound. There was no significant difference in the frequency of MN between males and females, but males had significantly more MN than sexually immature flounder. Flounder over the entire sampling area had increased levels of MN during the fall months of the year. This is probably influenced by the maternal cycle of gonadal maturation.

  12. Fine structure of Chloromyxum menticirrhi n. sp. (Myxozoa) infecting the urinary bladder of the marine teleost Menticirrhus americanus (Sciaenidae) in Southern Brazil.

    PubMed

    Casal, Graça; Garcia, Patrícia; Matos, Patrícia; Monteiro, Emanuel; Matos, Edilson; Azevedo, Carlos

    2009-05-01

    A myxosporidian was found in the urinary bladder of the teleost Menticirrhus americanus Linnaeus, 1758 (Sciaenidae) collected from the South Atlantic coast of Brazil. Polysporic amoeboid plasmodia containing sporoblasts, developing pansporoblasts and spores were free in the bladder lumen. The prevalence of infection was 17.64% (15/85). Unfixed spores were spherical to subspherical, on average 10.5microm long, 9.8microm wide and 10.1microm thick (n=25), and fixed spores measured 10.1 x 9.5 x 9.7microm. The two spore valves were of equal size and each possessed prominent sutural lines and about 41 (37-45) surface ridges aligned parallel with the suture line. These ridges gave transverse sections a cog-wheel-like outline. The spores contained four pyriform polar capsules of equal size (3.20 x 2.0microm) (n=25) (fixed), each with a polar filament having 3-4 (rarely 5) coils. The binucleate sporoplasm was irregular in shape, with granular matrix and randomly distributed dense bodies. The shape and dimensions of the spore, as well as the number, position and arrangement of the surface ridges, polar capsules and polar filament indicate that this is a new species, herein designated Chloromyxum menticirrhi. The gill, liver, gall bladder and intestine of the host showed no abnormalities.

  13. Six months of disuse during hibernation does not increase intracortical porosity or decrease cortical bone geometry, strength, or mineralization in black bear (Ursus americanus) femurs.

    PubMed

    McGee-Lawrence, Meghan E; Wojda, Samantha J; Barlow, Lindsay N; Drummer, Thomas D; Bunnell, Kevin; Auger, Janene; Black, Hal L; Donahue, Seth W

    2009-07-22

    Disuse typically uncouples bone formation from resorption, leading to bone loss which compromises bone mechanical properties and increases the risk of bone fracture. Previous studies suggest that bears can prevent bone loss during long periods of disuse (hibernation), but small sample sizes have limited the conclusions that can be drawn regarding the effects of hibernation on bone structure and strength in bears. Here we quantified the effects of hibernation on structural, mineral, and mechanical properties of black bear (Ursus americanus) cortical bone by studying femurs from large groups of male and female bears (with wide age ranges) killed during pre-hibernation (fall) and post-hibernation (spring) periods. Bone properties that are affected by body mass (e.g. bone geometrical properties) tended to be larger in male compared to female bears. There were no differences (p>0.226) in bone structure, mineral content, or mechanical properties between fall and spring bears. Bone geometrical properties differed by less than 5% and bone mechanical properties differed by less than 10% between fall and spring bears. Porosity (fall: 5.5+/-2.2%; spring: 4.8+/-1.6%) and ash fraction (fall: 0.694+/-0.011; spring: 0.696+/-0.010) also showed no change (p>0.304) between seasons. Statistical power was high (>72%) for these analyses. Furthermore, bone geometrical properties and ash fraction (a measure of mineral content) increased with age and porosity decreased with age. These results support the idea that bears possess a biological mechanism to prevent disuse and age-related osteoporoses.

  14. Influence of drift and admixture on population structure of American black bears (Ursus americanus) in the Central Interior Highlands, USA, 50 years after translocation

    USGS Publications Warehouse

    Puckett, Emily E.; Kristensen, Thea V.; Wilton, Clay M.; Lyda, Sara B.; Noyce, Karen V.; Holahan, Paula M.; Leslie,, David M.; Beringer, J.; Belant, Jerrold L.; White, D.; Eggert, L.S.

    2014-01-01

    Bottlenecks, founder events, and genetic drift often result in decreased genetic diversity and increased population differentiation. These events may follow abundance declines due to natural or anthropogenic perturbations, where translocations may be an effective conservation strategy to increase population size. American black bears (Ursus americanus) were nearly extirpated from the Central Interior Highlands, USA by 1920. In an effort to restore bears, 254 individuals were translocated from Minnesota, USA, and Manitoba, Canada, into the Ouachita and Ozark Mountains from 1958 to 1968. Using 15 microsatellites and mitochondrial haplotypes, we observed contemporary genetic diversity and differentiation between the source and supplemented populations. We inferred four genetic clusters: Source, Ouachitas, Ozarks, and a cluster in Missouri where no individuals were translocated. Coalescent models using approximate Bayesian computation identified an admixture model as having the highest posterior probability (0.942) over models where the translocation was unsuccessful or acted as a founder event. Nuclear genetic diversity was highest in the source (AR = 9.11) and significantly lower in the translocated populations (AR = 7.07-7.34; P = 0.004). The Missouri cluster had the lowest genetic diversity (AR = 5.48) and served as a natural experiment showing the utility of translocations to increase genetic diversity following demographic bottlenecks. Differentiation was greater between the two admixed populations than either compared to the source, suggesting that genetic drift acted strongly over the eight generations since the translocation. The Ouachitas and Missouri were previously hypothesized to be remnant lineages. We observed a pretranslocation remnant signature in Missouri but not in the Ouachitas.

  15. Serological survey of selected canine viral pathogens and zoonoses in grizzly bears (Ursus arctos horribilis) and black bears (Ursus americanus) from Alaska.

    PubMed

    Chomel, B B; Kasten, R W; Chappuis, G; Soulier, M; Kikuchi, Y

    1998-12-01

    Between 1988 and 1991, 644 serum samples were collected from 480 grizzly bears (Ursus arctos horribilis) and 40 black bears (Ursus americanus) from Alaska, United States of America, and were tested for selected canine viral infections and zoonoses. Antibody prevalence in grizzly bears was 0% for parvovirus, 8.3% (40/480) for distemper, 14% (68/480) for infectious hepatitis, 16.5% (79/480) for brucellosis, 19% (93/480) for tularaemia and 47% (225/478) for trichinellosis. In black bears, prevalence ranged from 0% for distemper and parvovirus to 27.5% for trichinellosis and 32% for tularaemia. Antibody prevalence for brucellosis (2.5%) and tularaemia (32%) were identical for grizzly bears and black bears from the geographical area of interior Alaska. Links between differences in prevalence and the origin of the grizzly bears were observed. Antibodies to canine distemper virus and infectious hepatitis virus were mainly detected in grizzly bears from Kodiak Island and the Alaskan Peninsula. Brucellosis antibodies were prevalent in grizzly bears from western and northern Alaska, whereas tularaemia antibodies were detected in grizzly bears from interior Alaska and the Arctic. There was a strong gradient for antibodies to Trichinella spp. from southern to northern Alaska. For most diseases, antibody prevalence increased with age. However, for several infections, no antibodies were detected in grizzly bears aged from 0 to 2 years, in contrast to the presence of those infections in black bears. Grizzly bears served as excellent sentinels for surveillance of zoonotic infections in wildlife in Alaska.

  16. Discovery and description of a new trichostrongyloid species (Nematoda: Ostertagiinae), abomasal parasites in mountain goat, Oreamnos americanus, from the Western Cordillera of North America.

    PubMed

    Hoberg, Eric P; Abrams, Arthur; Pilitt, Patricia A; Jenkins, Emily J

    2012-08-01

    Marshallagia lichtenfelsi sp. n. is a dimorphic ostertagiine nematode occurring in the abomasum of mountain goats, Oreamnos americanus, from the Western Cordillera of North America. Major and minor morphotype males and females are characterized and distinguished relative to the morphologically similar Marshallagia marshalli / Marshallagia occidentalis from North America and Marshallagia dentispicularis, along with other congeners, from the Palearctic region. The configuration of the convoluted and irregular synlophe in the cervical region of males and females of M. lichtenfelsi is apparently unique, contrasting with a continuous and parallel system of ridges among those species of Marshallagia, including M. marshalli/M. occidentalis, which have been evaluated. Specimens of M. lichtenfelsi are further defined by the rectangular form of the accessory bursal membrane (width > length) in the major morphotype and by the trapezoidal Sjöberg's organ in the minor morphotype, in addition to specific attributes of the spicules and spicule tips. We regard 12 species, including the proposed new taxon, to be valid. Primary diagnostic characters are reviewed for Marshallagia and a framework is presented for standardization of future descriptions incorporating the synlophe in males and females and the structure of the spicules and genital cone in major and minor morphotype males. The center of diversity for species of Marshallagia is the mountain-steppe region of central Eurasia where 11 species (including the Holarctic M. marshalli) are recognized in association with Caprini, Rupicaprini, and Antelopinae; only 2 species occur in the Nearctic. In this assemblage, M. lichtenfelsi is endemic to North America and limited in host distribution to mountain goats. An intricate history for refugial isolation and population fragmentation demonstrated for mountain goats and wild sheep indicates the potential for considerable cryptic diversity for Marshallagia and other nematodes. Shifting

  17. Influence of drift and admixture on population structure of American black bears (Ursus americanus) in the Central Interior Highlands, USA, 50 years after translocation.

    PubMed

    Puckett, Emily E; Kristensen, Thea V; Wilton, Clay M; Lyda, Sara B; Noyce, Karen V; Holahan, Paula M; Leslie, David M; Beringer, Jeff; Belant, Jerrold L; White, Don; Eggert, Lori S

    2014-05-01

    Bottlenecks, founder events, and genetic drift often result in decreased genetic diversity and increased population differentiation. These events may follow abundance declines due to natural or anthropogenic perturbations, where translocations may be an effective conservation strategy to increase population size. American black bears (Ursus americanus) were nearly extirpated from the Central Interior Highlands, USA by 1920. In an effort to restore bears, 254 individuals were translocated from Minnesota, USA, and Manitoba, Canada, into the Ouachita and Ozark Mountains from 1958 to 1968. Using 15 microsatellites and mitochondrial haplotypes, we observed contemporary genetic diversity and differentiation between the source and supplemented populations. We inferred four genetic clusters: Source, Ouachitas, Ozarks, and a cluster in Missouri where no individuals were translocated. Coalescent models using approximate Bayesian computation identified an admixture model as having the highest posterior probability (0.942) over models where the translocation was unsuccessful or acted as a founder event. Nuclear genetic diversity was highest in the source (AR = 9.11) and significantly lower in the translocated populations (AR = 7.07-7.34; P = 0.004). The Missouri cluster had the lowest genetic diversity (AR = 5.48) and served as a natural experiment showing the utility of translocations to increase genetic diversity following demographic bottlenecks. Differentiation was greater between the two admixed populations than either compared to the source, suggesting that genetic drift acted strongly over the eight generations since the translocation. The Ouachitas and Missouri were previously hypothesized to be remnant lineages. We observed a pretranslocation remnant signature in Missouri but not in the Ouachitas. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

  18. Substrate-Driven Convergence of the Microbial Community in Lignocellulose-Amended Enrichments of Gut Microflora from the Canadian Beaver (Castor canadensis) and North American Moose (Alces americanus).

    PubMed

    Wong, Mabel T; Wang, Weijun; Lacourt, Michael; Couturier, Marie; Edwards, Elizabeth A; Master, Emma R

    2016-01-01

    Strategic enrichment of microcosms derived from wood foragers can facilitate the discovery of key microbes that produce enzymes for the bioconversion of plant fiber (i.e., lignocellulose) into valuable chemicals and energy. In this study, lignocellulose-degrading microorganisms from the digestive systems of Canadian beaver (Castor canadensis) and North American moose (Alces americanus) were enriched under methanogenic conditions for over 3 years using various wood-derived substrates, including (i) cellulose (C), (ii) cellulose + lignosulphonate (CL), (iii) cellulose + tannic acid (CT), and (iv) poplar hydrolysate (PH). Substantial improvement in the conversion of amended organic substrates into biogas was observed in both beaver dropping and moose rumen enrichment cultures over the enrichment phases (up to 0.36-0.68 ml biogas/mg COD added), except for enrichments amended with tannic acid where conversion was approximately 0.15 ml biogas/mg COD added. Multiplex-pyrosequencing of 16S rRNA genes revealed systematic shifts in the population of Firmicutes, Bacteroidetes, Chlorobi, Spirochaetes, Chloroflexi, and Elusimicrobia in response to the enrichment. These shifts were predominantly substrate driven, not inoculum driven, as revealed by both UPGMA clustering pattern and OTU distribution. Additionally, the relative abundance of multiple OTUs from poorly defined taxonomic lineages increased from less than 1% to 25-50% in microcosms amended with lignocellulosic substrates, including OTUs from classes SJA-28, Endomicrobia, orders Bacteroidales, OPB54, and family Lachnospiraceae. This study provides the first direct comparison of shifts in microbial communities that occurred in different environmental samples in response to multiple relevant lignocellulosic carbon sources, and demonstrates the potential of enrichment to increase the abundance of key lignocellulolytic microorganisms and encoded activities.

  19. Isolation and Genetic Characterization of Toxoplasma gondii from Black Bears (Ursus americanus), Bobcats (Lynx rufus), and Feral Cats (Felis catus) from Pennsylvania.

    PubMed

    Dubey, Jitender P; Verma, Shiv K; Calero-Bernal, Rafael; Cassinelli, Ana B; Kwok, Oliver C H; Van Why, Kyle; Su, Chunlei; Humphreys, Jan G

    2015-01-01

    Toxoplasma gondii infects virtually all warm-blooded hosts worldwide. Recently, attention has been focused on the genetic diversity of the parasite to explain its pathogenicity in different hosts. It has been hypothesized that interaction between feral and domestic cycles of T. gondii may increase unusual genotypes in domestic cats and facilitate transmission of potentially more pathogenic genotypes to humans, domestic animals, and wildlife. In the present study, we tested black bear (Ursus americanus), bobcat (Lynx rufus), and feral cat (Felis catus) from the state of Pennsylvania for T. gondii infection. Antibodies to T. gondii were found in 32 (84.2%) of 38 bears, both bobcats, and 2 of 3 feral cats tested by the modified agglutination test (cut off titer 1:25). Hearts from seropositive animals were bioassayed in mice, and viable T. gondii was isolated from 3 of 32 bears, 2 of 2 bobcats, and 2 of 3 feral cats. DNA isolated from culture-derived tachyzoites of these isolates was characterized using multilocus PCR-RFLP markers. Three genotypes were revealed, including ToxoDB PCR-RFLP genotype #1 or #3 (Type II, 1 isolate), #5 (Type 12, 3 isolates), and #216 (3 isolates), adding to the evidence of genetic diversity of T. gondii in wildlife in Pennsylvania. Pathogenicity of 3 T. gondii isolates (all #216, 1 from bear, and 2 from feral cat) was determined in outbred Swiss Webster mice; all three were virulent causing 100% mortality. Results indicated that highly mouse pathogenic strains of T. gondii are circulating in wildlife, and these strains may pose risk to infect human through consuming of game meat.

  20. Substrate-Driven Convergence of the Microbial Community in Lignocellulose-Amended Enrichments of Gut Microflora from the Canadian Beaver (Castor canadensis) and North American Moose (Alces americanus)

    PubMed Central

    Wong, Mabel T.; Wang, Weijun; Lacourt, Michael; Couturier, Marie; Edwards, Elizabeth A.; Master, Emma R.

    2016-01-01

    Strategic enrichment of microcosms derived from wood foragers can facilitate the discovery of key microbes that produce enzymes for the bioconversion of plant fiber (i.e., lignocellulose) into valuable chemicals and energy. In this study, lignocellulose-degrading microorganisms from the digestive systems of Canadian beaver (Castor canadensis) and North American moose (Alces americanus) were enriched under methanogenic conditions for over 3 years using various wood-derived substrates, including (i) cellulose (C), (ii) cellulose + lignosulphonate (CL), (iii) cellulose + tannic acid (CT), and (iv) poplar hydrolysate (PH). Substantial improvement in the conversion of amended organic substrates into biogas was observed in both beaver dropping and moose rumen enrichment cultures over the enrichment phases (up to 0.36–0.68 ml biogas/mg COD added), except for enrichments amended with tannic acid where conversion was approximately 0.15 ml biogas/mg COD added. Multiplex-pyrosequencing of 16S rRNA genes revealed systematic shifts in the population of Firmicutes, Bacteroidetes, Chlorobi, Spirochaetes, Chloroflexi, and Elusimicrobia in response to the enrichment. These shifts were predominantly substrate driven, not inoculum driven, as revealed by both UPGMA clustering pattern and OTU distribution. Additionally, the relative abundance of multiple OTUs from poorly defined taxonomic lineages increased from less than 1% to 25–50% in microcosms amended with lignocellulosic substrates, including OTUs from classes SJA-28, Endomicrobia, orders Bacteroidales, OPB54, and family Lachnospiraceae. This study provides the first direct comparison of shifts in microbial communities that occurred in different environmental samples in response to multiple relevant lignocellulosic carbon sources, and demonstrates the potential of enrichment to increase the abundance of key lignocellulolytic microorganisms and encoded activities. PMID:27446004

  1. RAD genotyping reveals fine-scale genetic structuring and provides powerful population assignment in a widely distributed marine species, the American lobster (Homarus americanus).

    PubMed

    Benestan, Laura; Gosselin, Thierry; Perrier, Charles; Sainte-Marie, Bernard; Rochette, Rémy; Bernatchez, Louis

    2015-07-01

    Deciphering genetic structure and inferring connectivity in marine species have been challenging due to weak genetic differentiation and limited resolution offered by traditional genotypic methods. The main goal of this study was to assess how a population genomics framework could help delineate the genetic structure of the American lobster (Homarus americanus) throughout much of the species' range and increase the assignment success of individuals to their location of origin. We genotyped 10 156 filtered SNPs using RAD sequencing to delineate genetic structure and perform population assignment for 586 American lobsters collected in 17 locations distributed across a large portion of the species' natural distribution range. Our results revealed the existence of a hierarchical genetic structure, first separating lobsters from the northern and southern part of the range (FCT  = 0.0011; P-value = 0.0002) and then revealing a total of 11 genetically distinguishable populations (mean FST  = 0.00185; CI: 0.0007-0.0021, P-value < 0.0002), providing strong evidence for weak, albeit fine-scale population structuring within each region. A resampling procedure showed that assignment success was highest with a subset of 3000 SNPs having the highest FST . Applying Anderson's (Molecular Ecology Resources, 2010, 10, 701) method to avoid 'high-grading bias', 94.2% and 80.8% of individuals were correctly assigned to their region and location of origin, respectively. Lastly, we showed that assignment success was positively associated with sample size. These results demonstrate that using a large number of SNPs improves fine-scale population structure delineation and population assignment success in a context of weak genetic structure. We discuss the implications of these findings for the conservation and management of highly connected marine species, particularly regarding the geographic scale of demographic independence. © 2015 John Wiley & Sons Ltd.

  2. Incidence of Infestation and Larval Success of Emerald Ash Borer (Agrilus planipennis) on White Fringetree (Chionanthus virginicus), Chinese Fringetree (Chionanthus retusus), and Devilwood (Osmanthus americanus).

    PubMed

    Cipollini, Don; Rigsby, Chad M

    2015-10-01

    We compared the incidence of infestation by emerald ash borer (EAB) and lilac borer on white fringetree to that of its Asian congener, Chinese fringetree, Chionanthus retusus, and a North American relative, devilwood, Osmanthus americanus. We also conducted laboratory bioassays to determine the suitability of these hosts for EAB larvae. At Spring Grove Cemetery and Arboretum in Cincinnati, Ohio, 9 of 28 white fringetrees examined were infested by EAB. Most of the white fringetrees had lilac borer infestation, and most of the trees infested by EAB also had lilac borer infestation. None of the 11 Chinese fringetrees examined were infested by either EAB or lilac borer. Each of the five devilwood individuals examined was infested by lilac borer, but not EAB. At The Morton Arboretum in Lisle, Illinois, 7 of 16 white fringetrees examined were infested by EAB, while none of the seven Chinese fringetrees examined were infested by either insect. A 40-d bioassay confirmed that white fringetree was an acceptable host, producing fourth-instar larvae that were smaller than those produced on a highly susceptible cultivar of green ash, Fraxinus pennsylvanica. No larvae survived on Chinese fringetree, and neonates were largely incapable of feeding on it. Two larvae survived on devilwood, reaching the second instar and excavating extensive galleries. Future work should be aimed at biotic and abiotic factors influencing the susceptibility of white fringetree, as well as further examination of close relatives for their vulnerability to EAB. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. A comparison of the structure of American (Homarus americanus) and European (Homarus gammarus) lobster cuticle with particular reference to shell disease susceptibility.

    PubMed

    Davies, Charlotte E; Whitten, Miranda M A; Kim, Anita; Wootton, Emma C; Maffeis, Thierry G G; Tlusty, Michael; Vogan, Claire L; Rowley, Andrew F

    2014-03-01

    The integument of arthropods is an important first-line defence against the invasion of parasites and pathogens. Once damaged, this can be subject to colonisation by microbial agents from the surrounding environment, which in crustaceans can lead to a condition termed shell disease syndrome. This condition has been reported in several crustacean species, including crabs and lobsters. The syndrome is a progressive condition where the outer cuticle becomes pitted and eroded, and in extreme cases is compromised, leaving animals susceptible to septicaemia. This study examined the susceptibility of juvenile American (Homarus americanus) and European (Homarus gammarus) lobsters to shell disease, as a result of mechanical damage. Scanning electron microscopy was used as a method to identify differences in the cuticle structure and consequences of mechanical damage. Claw regions were aseptically punctured, whilst carapaces were abraded using sterile sandpaper, to mimic natural damage. After a period of between 10 and 12 weeks, lobsters were sacrificed, fixed and stored for later examination. The carapace and claws of juvenile American lobsters were shown to be thinner and more vulnerable to abrasion damage than their European counterparts. In addition, the number and distribution of setal pits and pore canal openings also differed between the two species of lobster. Mechanical damage resulted in the formation of shell disease lesions on the claw and carapace of both lobster species. However, American lobsters, unlike their European counterparts, had extensive bacterial colonisation on the margins of these lesions. Overall, it is concluded that the cuticle of the American lobster is more susceptible to damage and resulting microbial colonisation. This may have implications for susceptibility of both species of lobster to shell disease syndrome.

  4. Inter-animal variability in the effects of C-type allatostatin on the cardiac neuromuscular system in the lobster Homarus americanus.

    PubMed

    Wiwatpanit, Teerawat; Powers, Brian; Dickinson, Patsy S

    2012-07-01

    Although the global effects of many modulators on pattern generators are relatively consistent among preparations, modulators can induce different alterations in different preparations. We examined the mechanisms that underlie such variability in the modulatory effects of the peptide C-type allatostatin (C-AST; pQIRYHQCYFNPISCF) on the cardiac neuromuscular system of the lobster Homarus americanus. Perfusion of C-AST through the semi-intact heart consistently decreased the frequency of ongoing contractions. However, the effect of C-AST on contraction amplitude varied between preparations, decreasing in some preparations and increasing in others. To investigate this variable effect, we examined the effects of C-AST both peripherally and centrally. When contractions of the myocardium were elicited by controlled stimuli, C-AST did not alter heart contraction at the periphery (myocardium or neuromuscular junction) in any hearts. However, when applied either to the semi-intact heart or to the cardiac ganglion (CG) isolated from hearts that responded to C-AST with increased contraction force, C-AST increased both motor neuron burst duration and the number of spikes per burst by about 25%. In contrast, CG output was increased only marginally in hearts that responded to C-AST with a decrease in contraction amplitude, suggesting that the decrease in amplitude in those preparations resulted from decreased peripheral facilitation. Our data suggest that the differential effects of a single peptide on the cardiac neuromuscular system are due solely to differential effects of the peptide on the pattern generator; the extent to which the peptide induces increased burst duration is crucial in determining its overall effect on the system.

  5. Inter-animal variability in the effects of C-type allatostatin on the cardiac neuromuscular system in the lobster Homarus americanus

    PubMed Central

    Wiwatpanit, Teerawat; Powers, Brian; Dickinson, Patsy S.

    2012-01-01

    SUMMARY Although the global effects of many modulators on pattern generators are relatively consistent among preparations, modulators can induce different alterations in different preparations. We examined the mechanisms that underlie such variability in the modulatory effects of the peptide C-type allatostatin (C-AST; pQIRYHQCYFNPISCF) on the cardiac neuromuscular system of the lobster Homarus americanus. Perfusion of C-AST through the semi-intact heart consistently decreased the frequency of ongoing contractions. However, the effect of C-AST on contraction amplitude varied between preparations, decreasing in some preparations and increasing in others. To investigate this variable effect, we examined the effects of C-AST both peripherally and centrally. When contractions of the myocardium were elicited by controlled stimuli, C-AST did not alter heart contraction at the periphery (myocardium or neuromuscular junction) in any hearts. However, when applied either to the semi-intact heart or to the cardiac ganglion (CG) isolated from hearts that responded to C-AST with increased contraction force, C-AST increased both motor neuron burst duration and the number of spikes per burst by about 25%. In contrast, CG output was increased only marginally in hearts that responded to C-AST with a decrease in contraction amplitude, suggesting that the decrease in amplitude in those preparations resulted from decreased peripheral facilitation. Our data suggest that the differential effects of a single peptide on the cardiac neuromuscular system are due solely to differential effects of the peptide on the pattern generator; the extent to which the peptide induces increased burst duration is crucial in determining its overall effect on the system. PMID:22675192

  6. Juvenile winter flounder (Pseudopleuronectes americanus) and summer flounder (Paralichthys dentatus) utilization of Southern New England nurseries: Comparisons among estuarine, tidal river, and coastal lagoon shallow-water habitats.

    PubMed

    Taylor, David L; McNamee, Jason; Lake, John; Gervasi, Carissa L; Palance, Danial G

    2016-09-01

    This study evaluated the relative importance of the N arragansett Bay estuary (RI and MA, USA), and associated tidal rivers and coastal lagoons, as nurseries for juvenile winter flounder, Pseudopleuronectes americanus, and summer flounder, Paralichthys dentatus. Winter flounder (WF) and summer flounder (SF) abundance and growth were measured from May to October (2009-2013) and served as indicators for the use and quality of shallow-water habitats (water depth < 1.5-3.0 m). These bioindicators were then analyzed with respect to physiochemical conditions to determine the mechanisms underlying intra-specific habitat selection. WF and SF abundances were greatest in late May and June (maximum monthly mean = 4.9 and 0.55 flounder/m(2) for WF and SF, respectively), and were significantly higher in the tidal rivers relative to the bay and lagoons. Habitat-related patterns in WF and SF abundance were primarily governed by their preferences for oligohaline (0.1-5 ppt) and mesohaline (6-18 ppt) waters, but also their respective avoidance of hypoxic conditions (< 4 mg DO/L) and warm water temperatures (> 25 °C). Flounder habitat usage was also positively related to sediment organic content, which may be due to these substrates having sufficiently high prey densities. WF growth rates (mean = 0.25 ± 0.14 mm/d) were negatively correlated with the abundance of conspecifics, whereas SF growth (mean = 1.39 ± 0.46 mm/d) was positively related to temperature and salinity. Also, contrary to expectations, flounder occupied habitats that offered no ostensible advantage in intra-specific growth rates. WF and SF exposed to low salinities in certain rivers likely experienced increased osmoregulatory costs, thereby reducing energy for somatic growth. Low-salinity habitats, however, may benefit flounder by providing refugia from predation or reduced competition with other estuarine fishes and macro-invertebrates. Examining WF and SF abundance and growth across each species' broader

  7. Juvenile winter flounder (Pseudopleuronectes americanus) and summer flounder (Paralichthys dentatus) utilization of Southern New England nurseries: Comparisons among estuarine, tidal river, and coastal lagoon shallow-water habitats

    PubMed Central

    Taylor, David L.; McNamee, Jason; Lake, John; Gervasi, Carissa L.; Palance, Danial G.

    2016-01-01

    This study evaluated the relative importance of the N arragansett Bay estuary (RI and MA, USA), and associated tidal rivers and coastal lagoons, as nurseries for juvenile winter flounder, Pseudopleuronectes americanus, and summer flounder, Paralichthys dentatus. Winter flounder (WF) and summer flounder (SF) abundance and growth were measured from May to October (2009–2013) and served as indicators for the use and quality of shallow-water habitats (water depth < 1.5–3.0 m). These bioindicators were then analyzed with respect to physiochemical conditions to determine the mechanisms underlying intra-specific habitat selection. WF and SF abundances were greatest in late May and June (maximum monthly mean = 4.9 and 0.55 flounder/m2 for WF and SF, respectively), and were significantly higher in the tidal rivers relative to the bay and lagoons. Habitat-related patterns in WF and SF abundance were primarily governed by their preferences for oligohaline (0.1–5 ppt) and mesohaline (6–18 ppt) waters, but also their respective avoidance of hypoxic conditions (< 4 mg DO/L) and warm water temperatures (> 25 °C). Flounder habitat usage was also positively related to sediment organic content, which may be due to these substrates having sufficiently high prey densities. WF growth rates (mean = 0.25 ± 0.14 mm/d) were negatively correlated with the abundance of conspecifics, whereas SF growth (mean = 1.39 ± 0.46 mm/d) was positively related to temperature and salinity. Also, contrary to expectations, flounder occupied habitats that offered no ostensible advantage in intra-specific growth rates. WF and SF exposed to low salinities in certain rivers likely experienced increased osmoregulatory costs, thereby reducing energy for somatic growth. Low-salinity habitats, however, may benefit flounder by providing refugia from predation or reduced competition with other estuarine fishes and macro-invertebrates. Examining WF and SF abundance and growth across each species’ broader

  8. Effects of climatic, socio-economic and behavioural factors on the transmission of hookworm (Necator americanus) on two low-country plantations in Sri Lanka.

    PubMed

    Gunawardena, G S A; Karunaweera, N D; Ismail, M M

    2005-09-01

    The climatic, socio-economic and behavioural factors influencing hookworm (Necator americanus) infection in Sri Lanka were explored between February 2000 and June 2001. In February 2000, a single stool sample was collected from each of the 477 subjects investigated, who were aged 2-74 years (median = 13 years) and lived on the 'lowcountry' Maliboda and Ayr plantations. The 'baseline' prevalence (28.5%) and intensity of hookworm infection (0- 4828.5 eggs/g faeces, with a mean of 128.4 eggs/g) were then determined by examining these initial samples, as Kato-Katz smears. Subsequently, each participant was treated with a single, 500-mg dose of mebendazole and then followed-up, at monthly intervals, for the next 15 months. Whenever a subject was found smear-positive for hookworm eggs at one of the monthly follow-ups, he or she was treated again with mebendazole. This approach allowed the monthly incidence of hookworm infection to be determined for each subject, assuming that subjects became smear-positive approximately 6 weeks post-infection. During the study period, rainfall and mean temperature were recorded daily and then converted to monthly values so that the relationship between the incidence of infection over each month and the rainfall and mean temperature over the same period could be explored. In addition, potentially relevant data on the socio-economic status and behaviour of each subject were collected, in questionnaire-based interviews with the adult subjects and the caregivers of the children investigated. Odds ratios (OR) and their 95% confidence intervals (CI) were then calculated for each factor that might increase the risk of hookworm infection. The monthly incidence of hookworm infection showed three peaks -- in September 2000 (21.3%), January 2001 (20.8%) and May 2001 (17.5%) -- at Maliboda, and two peaks -- in September 2000 (25.0%) and February 2001 (29.2%) -- at Ayr. With the data for all subjects combined, incidence showed a statistically

  9. Foot preferences during resting in wildfowl and waders.

    PubMed

    Randler, Christoph

    2007-03-01

    Footedness in birds has been reported, e.g., in parrots and chickens, but the direction of footedness remained unclear. Is a bird left-footed because it uses its left foot for holding and handling food, or is it right-footed because it uses the right foot for stabilisation and balancing while perching? In 2004 and 2006 I examined footedness in wildfowl and waders while the birds were performing a single task: roosting on the ground on one foot. Avocet (Recurvirostra avosetta), northern shoveller (Anas clypeata), oystercatcher (Haematopus ostralegus), and Eurasian curlew (Numenius arquata) were right-footed. Another 21 species did not show any significant foot preferences. This study provides some evidence that asymmetries in preferential foot use in birds may be triggered by a preference during postural control.

  10. Demography of a breeding population of whimbrel (Numenius phaeopus) near Churchill, Manitoba, Canada

    NASA Astrophysics Data System (ADS)

    Perz, Johanna

    I used a GIS raster layer of an area in the Churchill, Manitoba region to investigate the effect of breeding habitat on demography and density of Whimbrel from 2010 through 2013. Program MARK was used to quantify adult and daily nest survival. Apparent annual survival of 0.73 +/- 0.06 SE (95% CI = 0.60-0.83) did not significantly differ between sexes or habitats and was lower than expected based on longevity records and estimates for other large-bodied shorebirds. Nest success, corrected for exposure days, was highly variable, ranging from a low of 3% (95% CI = 0-12%) in 2011 to a high of 71% (95% CI = 54-83%) in 2013. The highest rate of nest survival occurred in the spring with the warmest mean temperature. I developed a generalized linear model (GLM) with a negative-binomial distribution from random plots that were surveyed for abundance to extrapolate a local breeding population size of 410 +/- 230 SE and density of 3.2 birds per square km +/- 1.8 SE. The result of my study suggests that other aspects of habitat not captured by the land cover categories may be more important to population dynamics.

  11. Expression, purification, and molecular analysis of the Necator americanus glutathione S-transferase 1 (Na-GST-1): a production process developed for a lead candidate recombinant hookworm vaccine antigen.

    PubMed

    Goud, Gaddam Narsa; Deumic, Vehid; Gupta, Richi; Brelsford, Jill; Zhan, Bin; Gillespie, Portia; Plieskatt, Jordan L; Tsao, Eric I; Hotez, Peter J; Bottazzi, Maria Elena

    2012-06-01

    The enzyme Necator americanus glutathione S-transferase 1 (Na-GST-1) belongs to a unique Nu class of GSTs and is a lead candidate antigen in a bivalent human hookworm vaccine. Here we describe the expression of Na-GST-1 in the yeast Pichia pastoris at the 20 L manufacturing scale and its purification process performed by three chromatographic steps, comprised of a Q Sepharose XL anion exchange column, followed by a Butyl Sepharose HP hydrophobic affinity column and a Superdex 75 size-exclusion column. Approximately 1.5 g of recombinant protein was recovered at an overall process yield of 51%, with a purity grade of 98% and the absence of detectable host cell protein. By mass spectrometry the recombinant protein exhibits a mass of 23,676Da, which closely matches the predicted molecular mass of the protein. The expression and purification methods described here are suitable for further scale-up product development and for its use to design formulation processes suitable to generate a vaccine for clinical testing. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Analysis of expressed sequence tags (ESTs) and gene expression changes under different growth conditions for the ciliate Anophryoides haemophila, the causative agent of bumper car disease in the American lobster (Homarus americanus).

    PubMed

    Acorn, Adam R; Clark, K Fraser; Jones, Sarah; Després, Béatrice M; Munro, Sarah; Cawthorn, Richard J; Greenwood, Spencer J

    2011-06-01

    The scuticociliate Anophryoides haemophila, causes bumper car disease in American lobster (Homarus americanus) in commercial holding facilities in Atlantic Canada. While the parasite has been recognized since the 1970s and much has been learned about its biology, minimal molecular characterization exists. With genome consortiums turning to model organisms like the ciliates Tetrahymena and Paramecium, the amount of relevant sequence data available has made sequence surveys more attractive for gene discovery in related ciliates. We sequenced 9984 expressed sequence tags (ESTs) from a non-normalized A. haemophila cDNA library to characterize gene expression patterns, functional gene distribution and to discover novel genes related to the parasitic life history. The A. haemophila ESTs were grouped into 843 clusters and singletons with 658 EST clusters having identifiable homologs, while 159 ESTs were unique and had no similarity to any sequences in the public databases. Not unexpectedly, about 67% of the A. haemophila ESTs have similarity to annotated and hypothetical genes from the related oligohymenophorean ciliate, Tetrahymena. Numerous cysteine proteases, hypothetical proteins and novel sequences possess putative secretory signal peptides suggesting that they may contribute to the pathogenesis of bumper car disease in lobster. Real time RT-qPCR analysis of cathepsin L and two homologs of cathepsin B did not show any changes in gene expression under varying in vitro growth conditions or during a modified-in vivo infection which may be suggestive of the opportunistic life history strategy of this ciliate.

  13. Habitat change by the formation of alien Crassostrea-reefs in the Wadden Sea and its role as feeding sites for waterbirds

    NASA Astrophysics Data System (ADS)

    Markert, Alexandra; Esser, Wiebke; Frank, Dietrich; Wehrmann, Achim; Exo, Klaus-Michael

    2013-10-01

    Non-indigenous Pacific oysters (Crassostrea gigas) have been invading the central Wadden Sea since 1998, predominantly settling on intertidal blue mussel (Mytilus edulis) beds which are increasingly transformed into Crassostrea-reefs. Pacific oysters are strong ecosystem engineers and the habitat change is considered to be a threat for waterbirds losing important feeding sites in the intertidal of the Wadden Sea. This study has increased our understanding of the use of foraging habitats by birds according to changing food resources. During the spring and autumn migration period in 2007, we recorded bird densities at two reef types varying in Pacific oyster density and at the adjacent sand flat as a reference site. We also recorded feeding behaviour, choice of prey and assessed peck and intake rate of three target species: Eurasian oystercatcher Haematopus ostralegus, Eurasian curlew Numenius arquata and European herring gull Larus argentatus. To evaluate the use of the Crassostrea-reef in the central Wadden Sea, we compared bird densities of the target species at different intertidal feeding habitats in various regions and compared the biomass intake of Eurasian oystercatcher feeding on different prey species. We show that Eurasian oystercatcher and Eurasian curlew have adapted to the new situation and learned to exploit the food supply offered by Crassostrea-reefs. While foraging mainly on Pacific oysters, Eurasian oystercatchers attained sustainable intake rates even though food resource at dense reef during autumn was very poor due to a lack in harvestable oysters. Consolidation of reefs limits the accessibility of prey for Eurasian oystercatchers whereas a successful recruitment of Pacific oysters enhances the suitability of the habitat. Eurasian curlew was promoted by the engineering effects of the Pacific oyster while feeding extensively on shore crabs at the reefs. In contrast, European herring gulls appear hampered in foraging during low tide and hereby

  14. X-ray structure of Na-ASP-2, a pathogenesis-related-1 protein from the nematode parasite, Necator americanus, and a vaccine antigen for human hookworm infection.

    PubMed

    Asojo, Oluwatoyin A; Goud, Gaddam; Dhar, Kajari; Loukas, Alex; Zhan, Bin; Deumic, Vehid; Liu, Sen; Borgstahl, Gloria E O; Hotez, Peter J

    2005-02-25

    Human hookworm infection is a major cause of anemia and malnutrition of adults and children in the developing world. As part of on-going efforts to control hookworm infection, The Human Hookworm Vaccine Initiative has identified candidate vaccine antigens from the infective L3 larval stages of the parasite, including a family of pathogenesis-related (PR) proteins known as the Ancylostoma-secreted proteins (ASPs). A novel crystal structure of Na-ASP-2, a PR-1 protein secreted by infective larvae of the human hookworm Necator americanus, has been solved to resolution limits of 1.68 A and to an R-factor of 17% using the recombinant protein expressed in and secreted by Pichia pastoris. The overall fold of Na-ASP-2 is a three-layer alphabetaalpha sandwich flanked by an N-terminal loop and a short, cysteine-rich C terminus. Our structure reveals a large central cavity that is flanked by His129 and Glu106, two residues that are well conserved in all parasitic nematode L3 ASPs. Na-ASP-2 has structural and charge similarities to chemokines, which suggests that Na-ASP-2 may be an extra-cellular ligand of an unknown receptor. Na-ASP-2 is a useful homology model for NIF, a natural antagonistic ligand of CR3 receptor. From these modeling studies, possible binding modes were predicted. In addition, this first structure of a PR-1 protein from parasitic helminths may shed light on the molecular basis of host-parasite interactions.

  15. Multiscale habitat relationships of snowshoe hares (Lepus americanus) in the mixed conifer landscape of the Northern Rockies, USA: Cross-scale effects of horizontal cover with implications for forest management.

    PubMed

    Holbrook, Joseph D; Squires, John R; Olson, Lucretia E; Lawrence, Rick L; Savage, Shannon L

    2017-01-01

    Snowshoe hares (Lepus americanus) are an ecologically important herbivore because they modify vegetation through browsing and serve as a prey resource for multiple predators. We implemented a multiscale approach to characterize habitat relationships for snowshoe hares across the mixed conifer landscape of the northern Rocky Mountains, USA. Our objectives were to (1) assess the relationship between horizontal cover and snowshoe hares, (2) estimate how forest metrics vary across the gradient of snowshoe hare use and horizontal cover, and (3) model and map snowshoe hare occupancy and intensity of use. Results indicated that both occupancy and intensity of use by snowshoe hares increased with horizontal cover and that the effect became stronger as intensity of use increased. This underscores the importance of dense horizontal cover to achieve high use, and likely density, of snowshoe hares. Forest structure in areas with high snowshoe hare use and horizontal cover was characterized as multistoried with dense canopy cover and medium-sized trees (e.g., 12.7-24.4 cm). The abundance of lodgepole pine (Pinus contorta) was associated with snowshoe hare use within a mixed conifer context, and the only species to increase in abundance with horizontal cover was Engelmann spruce (Picea engelmannii) and subalpine fir (Abies lasiocarpa). Our landscape-level modeling produced similar patterns in that we observed a positive effect of lodgepole pine and horizontal cover on both occupancy and use by snowshoe hares, but we also observed a positive yet parabolic effect of snow depth on snowshoe hare occupancy. This work is among the first to characterize the multiscale habitat relationships of snowshoe hares across a mixed conifer landscape as well as to map their occupancy and intensity of use. Moreover, our results provide stand- and landscape-level insights that directly relate to management agencies, which aids in conservation efforts of snowshoe hares and their associated

  16. Organochlorine-induced mortality and residues in long-billed curlews from Oregon

    USGS Publications Warehouse

    Blus, L.J.; Henny, Charles J.; Krynitsky, A.J.

    1985-01-01

    In order to determine possible sources of vitamin A for quail, 37 species of insects and other invertebrates were analyzed for vitamin A and for carotene, and 26 species of seeds and fruits were assayed for carotene. The invertebrates showed no trace of vitamin A; but 8 herbivorous invertebrates and the praying mantis contained carotene. Most of the plants contained carotene--some of them a lot (dotted smartweed, some legumes, sumac, roses, bittersweet, etc.). The amount of carotene varied among plants of the same species and even among fruits on the same plant.

  17. Effects of management practices on grassland birds: Long-billed Curlew

    USGS Publications Warehouse

    Dechant, Jill A.; Sondreal, Marriah L.; Johnson, Douglas H.; Igl, Lawrence D.; Goldade, Christopher M.; Rabie, Paul A.; Euliss, Betty R.

    1999-01-01

    Information on the habitat requirements and effects of habitat management on grassland birds were summarized from information in more than 5,500 published and unpublished papers. A range map is provided to indicate the relative densities of the species in North America, based on Breeding Bird Survey (BBS) data. Although birds frequently are observed outside the breeding range indicated, the maps are intended to show areas where managers might concentrate their attention. It may be ineffectual to manage habitat at a site for a species that rarely occurs in an area. The species account begins with a brief capsule statement, which provides the fundamental components or keys to management for the species. A section on breeding range outlines the current breeding distribution of the species in North America, including areas that could not be mapped using BBS data. The suitable habitat section describes the breeding habitat and occasionally microhabitat characteristics of the species, especially those habitats that occur in the Great Plains. Details on habitat and microhabitat requirements often provide clues to how a species will respond to a particular management practice. A table near the end of the account complements the section on suitable habitat, and lists the specific habitat characteristics for the species by individual studies. A special section on prey habitat is included for those predatory species that have more specific prey requirements. The area requirements section provides details on territory and home range sizes, minimum area requirements, and the effects of patch size, edges, and other landscape and habitat features on abundance and productivity. It may be futile to manage a small block of suitable habitat for a species that has minimum area requirements that are larger than the area being managed. The Brown-headed Cowbird (Molothrus ater) is an obligate brood parasite of many grassland birds. The section on cowbird brood parasitism summarizes rates of cowbird parasitism, host responses to parasitism, and factors that influence parasitism, such as nest concealment and host density. The impact of management depends, in part, upon a species' nesting phenology and biology. The section on breeding-season phenology and site fidelity includes details on spring arrival and fall departure for migratory populations in the Great Plains, peak breeding periods, the tendency to renest after nest failure or success, and the propensity to return to a previous breeding site. The duration and timing of breeding varies among regions and years. Species' response to management summarizes the current knowledge and major findings in the literature on the effects of different management practices on the species. The section on management recommendations complements the previous section and summarizes specific recommendations for habitat management provided in the literature. If management recommendations differ in different portions of the species' breeding range, recommendations are given separately by region. The literature cited contains references to published and unpublished literature on the management effects and habitat requirements of the species. This section is not meant to be a complete bibliography; for a searchable, annotated bibliography of published and unpublished papers dealing with habitat needs of grassland birds and their responses to habitat management, use the Grassland and Wetland Birds Bibliography on the home page of this resource.

  18. Distribution study on migratory bird (Scolopacidae: Numenius) in Surabaya, Indonesia: Estimating the effect of habitat and climate change

    NASA Astrophysics Data System (ADS)

    Desmawati, Iska; Indah Trisnawati D., T.; Kurnia, Ory; Hamdani, Albi; Fahmi, Mahsun; Fahmi, Mirza

    2017-06-01

    Migratory Birds are responding to recent climate change in variety of ways. Distribution study of migratory birds will help to understand climate change effect in ecosystem area. Its supported by natural resources all around Indonesia. One of this place is Surabaya city specially Wonorejo area. Wonorejo is one of the Important Bird Area (IBA), specifically for bird conserved by Indonesian law and migratory birds. This research aims to know that distribution study on migratory bird enhances the knowledge of climate change effect. The distribution study use mapping method and the environment variables study analyzed by multivariate analysis. The description about how to analize the climate change effect in this area will be described by map and ilustration model. The result show that migratory bird (Scolopacidae) use different area of preference habitat in Wonorejo during migratory season on 2010-2016. In particular, the details of population and scale is likely to characterize global change biodiversity of migratory birds research need to improve in future.

  19. The Effects of Habitat Type and Volcanic Eruptions on the Breeding Demography of Icelandic Whimbrels Numenius phaeopus

    PubMed Central

    Katrínardóttir, Borgný; Alves, José A.; Sigurjónsdóttir, Hrefna; Gunnarsson, Tómas G.

    2015-01-01

    Distinct preference of species for habitats is most often driven by long term differences in demographic rates between habitats. Estimating variation in those rates is key for developing successful conservation strategies. Stochastic events can interact with underlying variation in habitat quality in regulating demography but the opportunities to explore such interactions are rare. Whimbrels in Iceland show a strong preference for sparsely vegetated riverplains. Such habitats in Iceland face various threats, e.g., climate change, river regulation and spread of alien plant species. In this study we compared demographic parameters of breeding Whimbrels between riverplains and other habitats before, during and after volcanic eruption events to estimate the importance of the habitats for the species and the effect of ash deposit on breeding success. We found that an estimated minimum of 23% of the Icelandic population of Whimbrels and c. 10% of the world population of the species breed in riverplain habitats in Iceland. Whimbrels bred consistently at much higher densities in riverplain habitats than in other habitats and riverplains also had higher densities of pairs with fledglings although the proportion of successful breeders was similar between habitats. Predation by livestock may have had a considerable negative effect on breeding success on our study sites. Breeding was negatively affected by the volcanic activity, probably through the effects of ash on the invertebrate food supply, with breeding success being gradually worse closer to the eruption. Breeding success was equally affected by volcanism across habitats which differed in underlying habitat quality. This study gives an example of how populations can be regulated by factors which operate at different spatial scales, such as local variation in habitat quality and stochastic events which impact larger areas. PMID:26161860

  20. The Effects of Habitat Type and Volcanic Eruptions on the Breeding Demography of Icelandic Whimbrels Numenius phaeopus.

    PubMed

    Katrínardóttir, Borgný; Alves, José A; Sigurjónsdóttir, Hrefna; Hersteinsson, Páll; Gunnarsson, Tómas G

    2015-01-01

    Distinct preference of species for habitats is most often driven by long term differences in demographic rates between habitats. Estimating variation in those rates is key for developing successful conservation strategies. Stochastic events can interact with underlying variation in habitat quality in regulating demography but the opportunities to explore such interactions are rare. Whimbrels in Iceland show a strong preference for sparsely vegetated riverplains. Such habitats in Iceland face various threats, e.g., climate change, river regulation and spread of alien plant species. In this study we compared demographic parameters of breeding Whimbrels between riverplains and other habitats before, during and after volcanic eruption events to estimate the importance of the habitats for the species and the effect of ash deposit on breeding success. We found that an estimated minimum of 23% of the Icelandic population of Whimbrels and c. 10% of the world population of the species breed in riverplain habitats in Iceland. Whimbrels bred consistently at much higher densities in riverplain habitats than in other habitats and riverplains also had higher densities of pairs with fledglings although the proportion of successful breeders was similar between habitats. Predation by livestock may have had a considerable negative effect on breeding success on our study sites. Breeding was negatively affected by the volcanic activity, probably through the effects of ash on the invertebrate food supply, with breeding success being gradually worse closer to the eruption. Breeding success was equally affected by volcanism across habitats which differed in underlying habitat quality. This study gives an example of how populations can be regulated by factors which operate at different spatial scales, such as local variation in habitat quality and stochastic events which impact larger areas.

  1. Three monogeneans parasitic on marine sciaenid fish from Peru including description of Cynoscionicola veranoi n. sp. (Microcotylidae), and redescription of C. americanus Tantaleán, Martínez and Escalante, 1987 and Hargicotyle sciaenae Oliva and Luque, 1989 (Diclidophoridae).

    PubMed

    Chero, Jhon D; Cruces, Celso L; Saez, Gloria; Luque, José L

    2017-09-26

    Cynoscionicola veranoi n. sp. (Monogenea: Microcotylidae) is described based on specimens collected from the gills of lorna drum Sciaena deliciosa (Tschudi, 1846) (Sciaenidae) from Peru. The new species can be differentiated from the other congeneric species by the combination of the following characteristics: (1) haptor with two types of clamps, (2) number and shape of the spines in anterolateral pouches of genital atrium (10-11 curved spines and 3-4 short and bifid spines with a knob in each lateral margin), (3) number and shape of the spines in posterolateral pouches of genital atrium (13-18 bifid spines), (4) 4-6 small spherical unarmed pouches in the genital atrium, and (5) 10-15 testes. In addition, a redescription of Cynoscionicola americanus Tantaleán, Martínez and Escalante, 1987 and Hargicotyle sciaenae Oliva and Luque, 1989 (Diclidophoridae) based on examination of type material and newly collected specimens from snakehead kingcroaker Menticirrhus ophicephalus (Jenyns, 1840) and S. deliciosa (type hosts), respectively, are provided herein.

  2. Polymorphic microsatellite loci identified through development and cross-species amplification within shorebirds

    USGS Publications Warehouse

    Williams, I.; Guzzetti, B.M.; Gust, Judy R.; Sage, G.K.; Gill, R.E.; Tibbitts, T.L.; Sonsthagen, S.A.; Talbot, S.L.

    2012-01-01

    We developed microsatellite loci for demographic assessments of shorebirds, a group with limited markers. First, we isolated five dinucleotide repeat microsatellite loci from the Black Oystercatcher (Haematopodidae: Haematopus bachmani), and three from the Bristle-thighed Curlew (Scolopacidae: Numenius tahitiensis); both species are of conservation concern. All eight loci were polymorphic in their respective target species. Hbaμ loci were characterized by two to three alleles with observed heterozygosity ranging from 0.07 to 0.33, and two to nine alleles were detected for Nut loci with observed heterozygosity ranging from 0.08 to 0.72. No linkage disequilibrium or departures from Hardy–Weinberg equilibrium were observed. The eight loci were also tested for cross-species amplification in 12 other species within Charadriidae and Scolopacidae, and the results demonstrated transferability across several genera. We further tested all 14 species at 12 additional microsatellite markers developed for other shorebirds: Dunlin (Calidris alpina; four loci) and Ruff (Philomachus pugnax; eight loci). Two markers (Hbaμ4 and Ruff6) were polymorphic in 13 species, while two (Calp6 and Ruff9) were monomorphic. The remaining eight markers revealed polymorphism in one to nine species each. Our results provide further evidence that locus Ruff10 is sex-linked, contrary to the initial description. These markers can be used to enhance our understanding of shorebird biology by, for example, helping to determine migratory connectivity among breeding and wintering populations and detecting relatedness among individuals.

  3. 76 FR 36491 - Endangered and Threatened Wildlife and Plants; Eskimo Curlew; Initiation of 5-Year Status Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-22

    ... Labrador, feeding on berries in nearby uplands and invertebrates in intertidal habitats (Gill et al. 1998... (List) in the Code of Federal Regulations (CFR) at 50 CFR 17.11 (for animals) and 17.12 (for plants)....

  4. Diseases of American lobsters (Homarus americanus): a review.

    PubMed

    Cawthorn, Richard J

    2011-01-01

    The American lobster fishery is a significant economic driver in coastal communities of North America. Increasingly, the impacts of infectious disease are recognized as important components and factors in the population ecology and subsequent management of the lobster fishery. Both environmental and anthropogenic factors impact marine diseases. The review herein highlights aspects of several important bacterial, fungal and protistan diseases, including gaffkemia, shell disease, vibriosis, disease caused by species of Lagenidium, Haliphthoros and Fusarium, paramoebiasis and Bumper Car disease. As the global environment continues to change, these diseases could more severely affect both wild caught and impounded lobsters.

  5. Cadmium and copper metallothioneins in the American lobster, Homarus americanus

    SciTech Connect

    Engel, D.W.; Brouwer, M.

    1986-03-01

    Lobsters were fed cadmium-rich oysters for 28 days, and the induction of cadmium metallothionein and its relation to concentrations of cadmium, copper, and zinc in the digestive gland and gills was determined. A portion of the tissues also was retained for determining the cytosolic distribution of these metals by gel filtration and ion-exchange chromatography. The digestive gland contained a majority of the cadmium, copper, and zinc, and both cadmium and zinc were actively accumulated from the oysters. Gel chromatography of the digestive gland cytosol showed that initially only copper was bound to a protein with a molecular weight in the range of metallothionein (i.e., 10,000-7000). However, after feeding on cadmium-laden oysters for 28 days, both cadmium and copper were bound to the metallothioneinlike protein. Further purification of the cadmium/copper protein by ion-exchange chromatography showed that a large portion of the copper and all of the cadmium did not bind to DEAE-Sephacel. The induction of cadmium metallothionein in the digestive gland is correlated with tissue cadmium concentration. Coincident with the induction of the cadmium metallothionein was a cytosolic redistribution of copper. The distribution of zinc was not affected.

  6. Metallothionein-like protein in lobsters (Homarus americanus)

    SciTech Connect

    Ray, J.; White, M.

    1981-12-01

    A metallothionein-like protein (MLP) was isolated from naturally cadmium-contaminated lobster hepatopancreas, gills, and green glands. Between 76-99% of the total cadmium was associated with this protein (molecular weight 9,500 daltons) while the remainder was associated with both high (>68,000 daltons) and low (<6,000 daltons) molecular weight proteins. MLP was not present in uncontaminated lobster hepatopancreas and only 1% of the total cadmium was associated with the gel filtration fraction corresponding to the protein.

  7. Picture object recognition in an American black bear (Ursus americanus).

    PubMed

    Johnson-Ulrich, Zoe; Vonk, Jennifer; Humbyrd, Mary; Crowley, Marilyn; Wojtkowski, Ela; Yates, Florence; Allard, Stephanie

    2016-11-01

    Many animals have been tested for conceptual discriminations using two-dimensional images as stimuli, and many of these species appear to transfer knowledge from 2D images to analogous real life objects. We tested an American black bear for picture-object recognition using a two alternative forced choice task. She was presented with four unique sets of objects and corresponding pictures. The bear showed generalization from both objects to pictures and pictures to objects; however, her transfer was superior when transferring from real objects to pictures, suggesting that bears can recognize visual features from real objects within photographic images during discriminations.

  8. Factors affecting post-capture survivability of lobster Homarus americanus.

    PubMed

    Basti, David; Bricknell, Ian; Hoyt, Ken; Chang, Ernest S; Halteman, William; Bouchard, Deborah

    2010-06-11

    Technological advances in gear and fishing practices have driven the global expansion of the American lobster live seafood market. These changes have had a positive effect on the lobster industry by increasing capture efficiency. However, it is unknown what effect these improved methods will have on the post-capture fitness and survival of lobsters. This project utilized a repeated measures design to compare the physiological changes that occur in lobsters over time as the result of differences in depth, hauling rate, and storage methodology. The results indicate that lobsters destined for long distance transport or temporary storage in pounds undergo physiological disturbance as part of the capture process. These changes are significant over time for total hemocyte counts, crustacean hyperglycemic hormone, L-lactate, ammonia, and glucose. Repeated measures multivariate analysis of variance (MANOVA) for glucose indicates a significant interaction between depth and storage methodology over time for non-survivors. A Gram-negative bacterium, Photobacterium indicum, was identified in pure culture from hemolymph samples of 100% of weak lobsters. Histopathology revealed the presence of Gram-negative bacteria throughout the tissues with evidence of antemortem edema and necrosis suggestive of septicemia. On the basis of these findings, we recommend to the lobster industry that if a reduction in depth and hauling rate is not economically feasible, fishermen should take particular care in handling lobsters and provide them with a recovery period in recirculating seawater prior to land transport. The ecological role of P. indicum is not fully defined at this time. However, it may be an emerging opportunistic pathogen of stressed lobsters. Judicious preemptive antibiotic therapy may be necessary to reduce mortality in susceptible lobsters destined for high-density holding facilities.

  9. Grassland birds wintering at U.S. Navy facilities in southern Texas

    USGS Publications Warehouse

    Woodin, Marc C.; Skoruppa, Mary Kay; Bryan, Pearce D.; Ruddy, Amanda J.; Hickman, Graham C.

    2010-01-01

    transects during the study were Species of Conservation Concern: Le Conte’s Sparrow, Sedge Wren (Cistothorus platensis), Grasshopper Sparrow (Ammodramus savannarum), Long-billed Curlew (Numenius americanus), Sprague’s Pipit (Anthus spragueii), Cassin’s Sparrow (Aimophila cassinii), and Loggerhead Shrike (Lanius ludovicianus). Native grasslands consistently supported greater bird species richness than exotic grasslands. In one winter, exotic grasslands supported more birds than native grasslands.Native grasslands were determined to have more forb cover, more bare ground, and greater plant species richness than exotic grasslands, whereas exotic grasslands were characterized by more grass cover and relatively greater vegetation density during dry years. Not only did these individual measures differ between native and exotic grasslands, but components of variation also differed. In native grasslands, grass density and cover contributed more to variation, whereas in exotic grasslands, non-grass vegetation was a greater component of variation. Total bird numbers and bird species richness in native grasslands were related to the principal component that contained a measure of litter cover. Total bird numbers and bird species richness in exotic grasslands indicated no significant relationships with any of the principal components of variation.The two most common insect orders in native grasslands were Hymenoptera and Coleoptera, which accounted for 42 percent of all insects. The two most common insect orders in exotic grasslands were Hemiptera and Homoptera, which accounted for about 80 percent of all insects. Insect family richness was greater in exotic grasslands than in native grasslands in two of four seasons. Proportions of arachnid families were similar in native and exotic grasslands, but arachnid family richness was greater in exotic grasslands than in native grasslands.Abundance of seeds was greater in exotic than in native grasslands. However, seed diversity was

  10. Cultivation of Candidatus Liberibacter asiaticus and Ca. L. americanus associated with Huanglongbing

    USDA-ARS?s Scientific Manuscript database

    A new medium designated Liber A has been designed and used to successfully cultivate all three Candidatus Liberibacter species, the suspect causative agents of Huanglongbing (HLB) in citrus. The medium containing citrus vein extract and a growth factor sustained growth of Ca. Liberibacter species fo...

  11. Factors Affecting Moulting Patterns of Atlantic Lobster (Homarus americanus) in the East Coast of Canada

    NASA Astrophysics Data System (ADS)

    Vanderstichel, R.; Thakur, K. K.; Revie, C. W.; Lavallée, J.

    2016-02-01

    In recent years, there has been a significant increase in the proportion of soft-shelled lobsters caught in Atlantic Canada. Soft-shelled lobsters pose a severe economic challenge to the lobster industry due to low meat yield and poor survivability during holding and transportation. The objectives of this study were to describe the moulting patterns of lobster in Atlantic Canada and to identify factors associated with soft-shelled lobsters. We used routinely collected data by the Atlantic Lobster Moult and Quality monitoring project from a range of locations within two lobster fishing areas in southwestern Nova Scotia. We incorporated environmental (sea surface temperature) and geographical (depth) variables before applied logistic and time-series regression methods to analyze the data. The analyses included more than 119,000 samples from 2004 to 2014. The proportion of soft-shelled lobsters ranged from 9 to 38% during these years. The logistic model demonstrated that stage of moulting, sex of the lobster, level of hemolymph concentration and median depth of the fishing locations were highly associated with the shell hardness of lobsters. This model further indicated that the shell quality was significantly influenced by month of sampling and the fishing areas from which the lobsters were caught, suggesting seasonal and regional differences. Additionally, significant inter-year variability in the shell quality indicated potential impact of climatic variation during these years. This hypothesis is supported by our initial analysis suggesting that the hemolymph concentration is associated with changes in sea surface temperature and ongoing work which evaluates the impact of temperature fluctuation on shell quality will be presented. Findings from this study will be of value to the lobster industry in helping to determine optimal fishing areas and periods, to improve the shell quality of landed lobsters and therefore to increase economic returns.

  12. Soil Organic Matter Content Effects on Dermal Pesticide Bioconcentration in American Toads (Bufo Americanus)

    EPA Science Inventory

    Agricultural landscapes serve as active amphibian breeding grounds despite their seemingly poor habitat value. Activity of adults and dispersal of metamorphs to and from agricultural ponds occurs in most species from spring through late summer or early fall, a time that coincides...

  13. MOLECULAR CHARACTERIZATION OF THE LOBSTER (HOMARUS AMERICANUS) NHE SODIUM/PROTON ANTIPORTER. (R823068)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  14. Evidence for persistent bovine viral diarrhea virus infection in a captive mountain goat (Oreamnos americanus)

    USDA-ARS?s Scientific Manuscript database

    Bovine viral diarrhea viruses (BVDV) are pestiviruses that have been isolated from domestic and wild ruminants, and there is serologic evidence of pestiviral infection in more than 40 species of free-ranging and captive mammals. Vertical transmission can produce persistently infected animals that ar...

  15. Evidence for persistent Bovine viral diarrhea virus infection in a captive mountain goat (Oreamnos americanus).

    PubMed

    Nelson, Danielle D; Dark, Michael J; Bradway, Daniel S; Ridpath, Julia F; Call, Neill; Haruna, Julius; Rurangirwa, Fred R; Evermann, James F

    2008-11-01

    Bovine viral diarrhea (BVD) viruses are pestiviruses that have been isolated from domestic and wild ruminants. There is serologic evidence of pestiviral infection in more than 40 species of free-range and captive mammals. Vertical transmission can produce persistently infected animals that are immunotolerant to the infecting strain of Bovine viral diarrhea virus (BVDV) and shed virus throughout their lives. Seven species (white-tailed deer, mouse deer, eland, domestic cattle, alpaca, sheep, and pigs) have been definitively identified as persistently infected with BVDV. This study provides serological, molecular, immunohistochemical, and histological evidence for BVDV infection in 2 captive mountain goats from a zoological park in Idaho. The study was triggered by isolation of BVDV from tissues and immunohistochemical identification of viral antigen within lesions of a 7-month-old male mountain goat (goat 1). Blood was collected from other mountain goats and white-tailed and mule deer on the premises for BVDV serum neutralization, viral isolation, and reverse transcription polymerase chain reaction. One 3-month-old mountain goat (goat 2) was antibody negative and BVDV positive in serum samples collected 3 months apart. This goat subsequently died, and though still antibody negative, BVDV was isolated from tissues and identified by immunohistochemistry within lesions. Sequencing and phylogenetic analysis identified the isolates as BVDV-2. These findings provide evidence of persistent infection in a mountain goat, underscoring the need for pestivirus control strategies for wild ruminants in zoological collections.

  16. Relationship between dose of emamectin benzoate and molting response of ovigerous American lobsters (Homarus americanus).

    PubMed

    Waddy, S L; Merritt, V A; Hamilton-Gibson, M N; Aiken, D E; Burridge, L E

    2007-05-01

    A widely-prescribed treatment to control sea lice on cultured salmon is the administration of feed medicated with SLICE (active ingredient emamectin benzoate (EMB)). High doses of EMB can disrupt the molt cycle of ovigerous American lobsters, causing them to enter proecdysis prematurely and lose their attached eggs when the shell is cast. To determine the dose response to EMB, lobsters were forced to ingest doses that ranged from 0.05 to 0.39 microg g(-1). A significant proportion of lobsters given doses of 0.39 and 0.22 microg g(-1) (37% and 23%, respectively) molted prematurely, almost a year earlier than the control group. All the lobsters in the 0.05 and 0.12 microg g(-1) groups molted at the normal time and the mean time of molt was similar to that of the control group. Thus, the no-observed-effect level (NOEL) and lowest-observed-effect level (LOEL) of EMB on the molt cycle were 0.12 and 0.22 microg EMB g(-1) lobster, respectively. To acquire the LOEL, a 500-g lobster would have to consume 22 g of salmon feed medicated with SLICE at a level of 5 microg EMB g(-1) feed.

  17. Function of chemoreceptor organs in spatial orientation of the lobster, Homarus americanus: differences and overlap

    SciTech Connect

    Devine, D.V.; Atema, J.

    1982-08-01

    Three of the lobster's main chemoreceptor organs, the lateral and medial antennules (representing smell) and the dactylus-propodus segments of the walking legs (representing taste), are physiologically quite similar. The authors examined their role in spatial orientation in a food-odor stimulus field. Control animals almost always oriented correctly and immediately to an odor plume. Lobsters with unilateral ablations of lateral antennules lost this ability, but did not show preferential turning toward the intact side. Unilateral medial antennule ablation did not affect orientation. Removal of all aesthetasc hairs from one lateral antennule caused loss of orientation ability less severe than unilateral ablation of the entire lateral antennule. Lobsters with unilaterally ablated lateral antennules and blocked walking leg receptors turned preferentially toward the side of the intact antennule. Thus, it appears that intact lobsters orient in odor space by tropotaxis principally using aesthetasc receptor input. Since loss of appendages is relatively common in lobsters, this partial overlap of organ function may serve the animal well in nature.

  18. WINTER FLOUNDER PSUEDOPLEURONECTES AMERICANUS HATCHING SUCCESS AS A FUNCTION OF BURIAL DEPTH IN THE LABORATORY

    EPA Science Inventory

    Previous experiments have shown that viable hatch of winter flounder eggs is reduced when the eggs are buried by as little as one half of one egg diameter (approximately 0.5 mm of sediment). This sensitivity to burial has resulted in seasonal banning of dredging in several north...

  19. Soil Organic Matter Content Effects on Dermal Pesticide Bioconcentration in American Toads (Bufo Americanus)

    EPA Science Inventory

    Agricultural landscapes serve as active amphibian breeding grounds despite their seemingly poor habitat value. Activity of adults and dispersal of metamorphs to and from agricultural ponds occurs in most species from spring through late summer or early fall, a time that coincides...

  20. Sperm ultrastructure, morphometry, and abnormal morphology in American black bears (Ursus americanus).

    PubMed

    Brito, L F C; Sertich, P L; Stull, G B; Rives, W; Knobbe, M

    2010-11-01

    The objective of this study was to describe sperm ultrastructure, morphometry, and abnormal morphology in American black bears. Electroejaculation was successful in 53.8% (7/13) of the attempts, but urine contamination was common. Epididymal sperm samples were also obtained from five bears. Sperm had a paddle-like head shape and the ultrastructure was similar to that of most other mammals. The most striking particularity of black bear sperm ultrastructure was a tightening of the nucleus in the equatorial region. Although the differences were not significant in all bears, the overall decrease in sperm nucleus dimensions during transport from the caput epididymis to the cauda suggested increasing compaction of the nucleus during maturation. For ejaculated sperm, nucleus length, width, and base width were 4.9, 3.7, and 1.8 μm, respectively, whereas sperm head length, width, and base width were 6.6, 4.8, and 2.3 μm, and midpiece, tail (including midpiece), and total sperm lengths were 9.8, 68.8, and 75.3 μm. Evaluation of sperm cytoplasmic droplets in the epididymis revealed that proximal droplets start migrating toward a distal position in the caput epididymis and that the process was mostly completed by the time sperm reached the cauda epididymis. The proportion of morphologically normal sperm in the ejaculate was 35.6%; the most prevalent sperm defects were distal cytoplasmic droplets and bent/coiled tails. The morphology of abnormal sperm and the underlying ultrastructural defects were similar to that in other large domestic animals thus suggesting similar underlying pathogenesis of specific sperm defects and similar effects on fertility.

  1. Social and nonsocial category discriminations in a chimpanzee (Pan troglodytes) and American black bears (Ursus americanus).

    PubMed

    Vonk, Jennifer; Johnson-Ulrich, Zoe

    2014-09-01

    One captive adult chimpanzee and 3 adult American black bears were presented with a series of natural category discrimination tasks on a touch-screen computer. This is the first explicit comparison of bear and primate abilities using identical tasks, and the first test of a social concept in a carnivore. The discriminations involved a social relationship category (mother/offspring) and a nonsocial category involving food items. The social category discrimination could be made using knowledge of the overarching mother/offspring concept, whereas the nonsocial category discriminations could be made only by using perceptual rules, such as "choose images that show larger and smaller items of the same type." The bears failed to show above-chance transfer on either the social or nonsocial discriminations, indicating that they did not use either the perceptual rule or knowledge of the overarching concept of mother/offspring to guide their choices in these tasks. However, at least 1 bear remembered previously reinforced stimuli when these stimuli were recombined, later. The chimpanzee showed transfer on a control task and did not consistently apply a perceptual rule to solve the nonsocial task, so it is possible that he eventually acquired the social concept. Further comparisons between species on identical tasks assessing social knowledge will help illuminate the selective pressures responsible for a range of social cognitive skills.

  2. HEPATOPANCREATIC CALCIUM DISTRIBUTION IN THE LOBSTER (HOMARUS AMERICANUS) DETERMINED BY CONFOCAL MICROSCOPY. (R823068)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  3. DISTRIBUTION OF CALCIUM AND HEAVY METALS IN HEPATOPANCREAS OF THE ATLANTIC LOBSTER (HOMARUS AMERICANUS). (R823068)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  4. CALCIUM UPTAKE BY MITOCHONDRIA OF ATLANTIC LOBSTER (HOMARUS AMERICANUS). (R823068)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  5. Population viability and connectivity of the Louisiana black bear (Ursus americanus luteolus)

    USGS Publications Warehouse

    Laufenberg, Jared S.; Clark, Joseph D.

    2014-01-01

    From April 2010 to April 2012, global positioning system (GPS) radio collars were placed on 8 female and 23 male bears ranging from 1 to 11 years of age to develop a step-selection function model to predict routes and rates of interchange. For both males and females, the probability of a step being selected increased as the distance to natural land cover and agriculture at the end of the step decreased and as distance from roads at the end of a step increased. Of 4,000 correlated random walks, the least potential interchange was between TRB and TRC and between UARB and LARB, but the relative potential for natural interchange between UARB and TRC was high. The step-selection model predicted that dispersals between the LARB and UARB populations were infrequent but possible for males and nearly nonexistent for females. No evidence of natural female dispersal between subpopulations has been documented thus far, which is also consistent with model predictions.

  6. Exposure to the steroid hormone 20-hydroxyecdysone modulates agonistic interactions in male Homarus americanus.

    PubMed

    Reinhart, V L; Cromarty, S I; Sipala, M W; Kass-Simon, G

    2012-11-01

    In this study we present evidence that 20-hydroxyecdysone (20E) affects agonistic behavior in male American lobsters and that male and female animals differ in their response to the hormone. Thirty-minute staged fights were conducted between large males exposed either to artificial seawater (ASW) or 20E and small, anosmic opponents. The nephropores of both combatants were blocked. Fights were videotaped and quantitatively analyzed for aggressive, defensive and avoidance behaviors using an ethogram in which behaviors are ranked according to aggressiveness. Unlike female lobsters, exposing male lobsters to 20E did not increase their aggressive behavior; however, there was a marginally significant trend toward an increase in defensive behaviors with a lower aggressive content than in their ASW-exposed counterparts. The opponents of 20E-exposed animals performed significantly more aggressive behaviors than their counterparts. In fights with 20E-exposed animals, the overall aggressive intensity of the fight was increased and the animals performed a greater number of avoidance behaviors. Unlike the effects of 20E on females, where exposure to 20E caused an increase in overall agonistic arousal, males only exhibited a change in frequency of their behaviors. These findings suggest that while 20E affects both males and females in agonistic encounters, the nature of the effect is different for the two sexes.

  7. USE OF A RHODE ISLAND SALT POND BY JUVENILE WINTER FLOUNDER, PSEUDOPLEURONECTES AMERICANUS

    EPA Science Inventory

    We used a 1.75 m2 drop ring sampler in June and July of 2000 to quantify populations of juvenile flatfishes and other small nekton in Ninigret Pond, Rhode Island. The drop sampler was deployed in approximately 1 m of water from a boom mounted on the bow of a small boat. Abundance...

  8. Malathion immunotoxicity in the American lobster (Homarus americanus) upon experimental exposure.

    PubMed

    De Guise, Sylvain; Maratea, Jennifer; Perkins, Christopher

    2004-03-10

    A lobster die-off reduced the 1999 fall landings in western Long Island Sound by up to more then 99%. The die-off corresponded in time with the application of pesticides for the control of mosquitoes that carried West Nile virus, a new emerging disease in North America at the time. In order to determine the possible implication of pesticide application as a direct cause or contributing factor in the die-off, we studied the effects of experimental exposure to malathion on the health of lobsters. Lobsters were exposed in 20 gallon tanks, and the direct toxicity as well as sub-lethal effects on the immune system were determined. The 96 h LC50 for malathion upon single exposure was 38 microg/l. Malathion degraded rapidly in sea water, with 65-77% lost after 1 day and 83-96% lost after 3 days. Phagocytosis was significantly decreased 3 days after a single exposure to initial water concentrations as low as 5 ppb, when measured water concentrations were as low as 0.55 ppb. Similarly, effects on phagocytosis were observed at 1, 2 and 3 weeks after the initiation of weekly exposures. Cell counts did not differ significantly upon exposure to malathion. Malathion was not detected in muscle and hepatopancreas of exposed lobsters. Evaluation of phagocytosis is a sensitive indicator of subtle sub-lethal effects of malathion, and relatively small concentrations of malathion (6-7 times lower than the LC50) can affect lobster defense mechanisms.

  9. Bioaccumulation and Metabolic Effects of the Endocrine Disruptor Methoprene in the Lobster, Homarus americanus.

    PubMed

    Walker, Anna N; Bush, Parshall; Puritz, Jonathan; Wilson, Thomas; Chang, Ernest S; Miller, Tim; Holloway, Kenneth; Horst, Michael N

    2005-01-01

    Methoprene is a pesticide that acts as a juvenile hormone agonist. Although developed initially against insects, it has since been shown to have toxic effects on larval and adult crustaceans. Methoprene was one of several pesticides applied to the Western Long Island Sound (WLIS) watershed area during the summer of 1999; the other pesticides were malathion, resmethrin, and sumethrin. These pesticides were applied as part of a county-by-county effort to control the mosquito vector of West Nile Virus. Subsequently, the seasonal lobster catches from the WLIS have decreased dramatically. The lethality of the pesticides to lobsters had been unknown. We studied the effects of methoprene while other investigators studied effects of the other pesticides. We questioned whether methoprene, through its effects on larvae, adults or both, could have contributed to this decline. We found that low levels of methoprene had adverse effects on lobster larvae. It was toxic to stage II larvae at 1 ppb. Stage IV larvae were more resistant, but did exhibit significant increases in molt frequency beginning at exposures of 5 ppb. Juvenile lobsters exhibited variations in tissue susceptibility to methoprene: hepatopancreas appeared to be the most vulnerable, reflected by environmental concentrations of methoprene inhibiting almost all protein synthesis in this organ.Our results indicated that methoprene concentrates in the hepatopancreas, nervous tissue and epidermal cells of the adult lobster. Methoprene altered the synthesis and incorporation of chitoproteins (cuticle proteins) into adult postmolt lobster explant shells. SDS PAGE analyses of adult post-molt shell extracts revealed changes in the synthesis of chitoproteins in the methoprene-treated specimens, suggesting that methoprene affects the normal pathway of lobster cuticle synthesis and the quality of the post-molt shell. Although it is likely that a combination of factors led to the reduced lobster population in WLIS, methoprene may have contributed both by direct toxic effects and by disrupting homeostatic events under endocrine control.

  10. MOLECULAR CHARACTERIZATION OF THE LOBSTER (HOMARUS AMERICANUS) NHE SODIUM/PROTON ANTIPORTER. (R823068)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  11. Linking ocean acidification and warming to the larval development of the American lobster (Homarus americanus)

    NASA Astrophysics Data System (ADS)

    Waller, J. D.; Fields, D.; Wahle, R.; Mcveigh, H.; Greenwood, S.

    2016-02-01

    The American lobster upholds the most culturally and economically iconic fishery in New England. Over the past three decades lobster landings have risen steadily in northern New England as lobster populations have shifted northward, leaving policy makers and coastal communities wondering what the future of this fishery may hold. The underlying causes of this population shift are likely due to a suite of environmental stressors including increasing temperature and ocean acidification. In this study we investigated the interactive effects of IPCC predicted temperature and pH on key aspects of larval lobster development (size, survival, development time, respiration rate, swimming speed, prey consumption and gene expression). Our experiments showed that larvae raised in the high temperature treatments (19 °C) experienced significantly higher mortality than larvae in our control treatments (16 °C) with 50% mortality occurring in the high temperature treatment one week after hatching. The larvae in these high temperature treatments developed twice as fast and experienced respiration rates that were three times higher in the third and fourth larval stages. While temperature had a distinct effect, pH treatment had few significant effects on any of our measured parameters. These data suggest that projected end-century warming will have greater adverse effects than acidification on early larval survival, despite the hurrying effect of higher temperatures on lobster larval development and increase in physiological activity. There were no significant treatment effects on carapace length, dry weight, or carbon and nitrogen content. Analysis of swimming speed and gene expression (through RNA sequencing) are in progress. Understanding how the most vulnerable life stages of the lobster life cycle responds to climate change is essential in connecting the northward geographic shifts projected by habitat quality models, and the underlying physiological and genetic mechanisms that drive their ecology.

  12. HEPATOPANCREATIC CALCIUM DISTRIBUTION IN THE LOBSTER (HOMARUS AMERICANUS) DETERMINED BY CONFOCAL MICROSCOPY. (R823068)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  13. DISTRIBUTION OF CALCIUM AND HEAVY METALS IN HEPATOPANCREAS OF THE ATLANTIC LOBSTER (HOMARUS AMERICANUS). (R823068)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  14. CALCIUM UPTAKE BY MITOCHONDRIA OF ATLANTIC LOBSTER (HOMARUS AMERICANUS). (R823068)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  15. USE OF A RHODE ISLAND SALT POND BY JUVENILE WINTER FLOUNDER, PSEUDOPLEURONECTES AMERICANUS

    EPA Science Inventory

    We used a 1.75 m2 drop ring sampler in June and July of 2000 to quantify populations of juvenile flatfishes and other small nekton in Ninigret Pond, Rhode Island. The drop sampler was deployed in approximately 1 m of water from a boom mounted on the bow of a small boat. Abundance...

  16. WINTER FLOUNDER PSUEDOPLEURONECTES AMERICANUS HATCHING SUCCESS AS A FUNCTION OF BURIAL DEPTH IN THE LABORATORY

    EPA Science Inventory

    Previous experiments have shown that viable hatch of winter flounder eggs is reduced when the eggs are buried by as little as one half of one egg diameter (approximately 0.5 mm of sediment). This sensitivity to burial has resulted in seasonal banning of dredging in several north...

  17. Soil organic matter content effects on dermal pesticide bioconcentration in American toads (Bufo americanus).

    EPA Science Inventory

    Pesticides have been implicated as a major factor in global amphibian declines and may pose great risk to terrestrial phase amphibians moving to and from breeding ponds on agricultural landscapes. Dermal uptake from soil is known to occur in amphibians, but predicting pesticide a...

  18. Soil organic matter content effects on dermal pesticide bioconcentration in American toads (Bufo americanus).

    EPA Science Inventory

    Pesticides have been implicated as a major factor in global amphibian declines and may pose great risk to terrestrial phase amphibians moving to and from breeding ponds on agricultural landscapes. Dermal uptake from soil is known to occur in amphibians, but predicting pesticide a...

  19. Functional Organization of the Cardiac Ganglion of the Lobster, Homarus americanus.

    PubMed

    Mayeri, E

    1973-10-01

    External recording and stimulation, techniques were used to determine which neurons and interactions are essential for production of the periodic burst discharge in the lobster cardiac ganglion. Burst activity can be modulated by brief single shocks applied to the four small cells, but not by similar stimulation of the five large cells, suggesting that normally one or more small cells primarily determine burst rate and duration. Repetitive electrical stimulation of large cells initiates spike activity in small cells, probably via excitatory synaptic and/or electrotonic connections which may normally act to prolong bursts and decrease burst rate. Transection of the ganglion can result in burst activity in small cells in the partial or complete absence of large cell spike activity, but large cells isolated from small cell excitatory synaptic input by transection or by application of dinitrophenol do not burst. Generally, transections which decrease excitatory feedback to small cells are accompanied by an increase in burst rate, but mean spike frequency over an entire burst cycle stabilizes at the original level within 10-30 min for various groups of cells whose spike-initiating sites are still intact. These and previous results suggest that the system is two layered: one or more small cells generate the burst pattern and impose it on the large cells which are the system's motorneurons.

  20. Development of chemically mediated prey-search response in postlarval lobsters (Homarus americanus) through feeding experience.

    PubMed

    Daniel, P C; Bayer, R C

    1987-05-01

    Postlarval lobsters were fed live amphipods (Gammarus oceanicus), soft clam spat (Mya arenaria), or frozen brine shrimp (Artemia salina) for five weeks in order to determine by behavioral bioassay if chemically mediated prey-search behavior is established by feeding experience. Chemosensory responses of predatorily naive lobsters to live clam and amphipod metabolites were low and erratic. After five weeks, amphipod-fed lobsters had developed strong responses towards amphipod metabolites but not clam metabolites. In contrast, clam-fed lobsters did not develop responses to either prey. Chemical fractionation of amphipod metabolites indicated that attractants were confined to the same fraction as for prey extracts, i.e., polar, low-molecular-weight compounds. Survival (80-90%) was similar for each diet group; growth was greatest for amphipod-fed lobsters (100%), followed by clam-fed lobsters (72%) and brine shrimp-fed lobsters (18%); and feeding rates increased for amphipod-fed lobsters and decreased for clam-fed lobsters. Coloration of lobsters indicated that only amphipod diet provided desirable pigments. Differences in ingestive conditioning results between clamfed and amphipod-fed lobsters may have been related to (1) clam metabolites being qualitatively or quantitatively less attractive than amphipod metabolites or (2) differences in the predisposition of lobsters to show ingestive conditioning to different prey and their associated metabolites as a function of quality of prey as a diet.

  1. Functional Organization of the Cardiac Ganglion of the Lobster, Homarus americanus

    PubMed Central

    Mayeri, Earl

    1973-01-01

    External recording and stimulation, techniques were used to determine which neurons and interactions are essential for production of the periodic burst discharge in the lobster cardiac ganglion. Burst activity can be modulated by brief single shocks applied to the four small cells, but not by similar stimulation of the five large cells, suggesting that normally one or more small cells primarily determine burst rate and duration. Repetitive electrical stimulation of large cells initiates spike activity in small cells, probably via excitatory synaptic and/or electrotonic connections which may normally act to prolong bursts and decrease burst rate. Transection of the ganglion can result in burst activity in small cells in the partial or complete absence of large cell spike activity, but large cells isolated from small cell excitatory synaptic input by transection or by application of dinitrophenol do not burst. Generally, transections which decrease excitatory feedback to small cells are accompanied by an increase in burst rate, but mean spike frequency over an entire burst cycle stabilizes at the original level within 10–30 min for various groups of cells whose spike-initiating sites are still intact. These and previous results suggest that the system is two layered: one or more small cells generate the burst pattern and impose it on the large cells which are the system's motorneurons. PMID:19873680

  2. Detection and prevalence of four different hemotropic Mycoplasma spp. in Eastern North Carolina American black bears (Ursus americanus).

    PubMed

    Westmoreland, Lori S H; Stoskopf, Michael K; Maggi, Ricardo G

    2017-02-01

    Hemotropic Mycoplasma spp. are globally emerging, obligate parasitic, epierythrocytic bacteria that infect many vertebrates, including humans. Hemoplasma infection can cause acute life-threatening symptoms or lead to a chronic sub-clinical carrier state. Hemotropic Mycoplasma spp. transmission, prevalence, and host specificity are uncertain. The purpose of this study was to determine the molecular prevalence of Mycoplasma species in blood from 68 free-ranging black bears from the eastern coast of North Carolina. DNA amplification of Mycoplasma 16S rRNA gene identified four distinct species infecting 34/68 (50%) of the black bear blood samples, including Candidatus M. haematoparvum. The high prevalence of hemotropic Mycoplasma infection in this wildlife species highlights the importance of understanding intra and inter species transmission. Black bears may play a role in the transmission of hemotropic Mycoplasma spp. between animals, arthropod vectors, and humans. Further studies are needed to elucidate black bears as a potential reservoir for hemotropic Mycoplasma infections. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. The Effect of Elevated CO2 on the Growth and Food Consumption of Juvenile Winter Flounder Pseudopleuronectes Americanus

    EPA Science Inventory

    Increasing levels of atmospheric carbon dioxide are causing changes in seawater chemistry in the world’s oceans. In estuarine waters, atmospheric CO2 exacerbates already declining pH due to high productivity and respiration caused by cultural eutrophication. These two sources o...

  4. Preservation of bone mass and structure in hibernating black bears (Ursus americanus) through elevated expression of anabolic genes.

    PubMed

    Fedorov, Vadim B; Goropashnaya, Anna V; Tøien, Øivind; Stewart, Nathan C; Chang, Celia; Wang, Haifang; Yan, Jun; Showe, Louise C; Showe, Michael K; Donahue, Seth W; Barnes, Brian M

    2012-06-01

    Physical inactivity reduces mechanical load on the skeleton, which leads to losses of bone mass and strength in non-hibernating mammalian species. Although bears are largely inactive during hibernation, they show no loss in bone mass and strength. To obtain insight into molecular mechanisms preventing disuse bone loss, we conducted a large-scale screen of transcriptional changes in trabecular bone comparing winter hibernating and summer non-hibernating black bears using a custom 12,800 probe cDNA microarray. A total of 241 genes were differentially expressed (P < 0.01 and fold change >1.4) in the ilium bone of bears between winter and summer. The Gene Ontology and Gene Set Enrichment Analysis showed an elevated proportion in hibernating bears of overexpressed genes in six functional sets of genes involved in anabolic processes of tissue morphogenesis and development including skeletal development, cartilage development, and bone biosynthesis. Apoptosis genes demonstrated a tendency for downregulation during hibernation. No coordinated directional changes were detected for genes involved in bone resorption, although some genes responsible for osteoclast formation and differentiation (Ostf1, Rab9a, and c-Fos) were significantly underexpressed in bone of hibernating bears. Elevated expression of multiple anabolic genes without induction of bone resorption genes, and the down regulation of apoptosis-related genes, likely contribute to the adaptive mechanism that preserves bone mass and structure through prolonged periods of immobility during hibernation.

  5. The effect of soil type and climate on hookworm (Necator americanus) distribution in KwaZulu-Natal, South Africa.

    PubMed

    Mabaso, M L H; Appleton, C C; Hughes, J C; Gouws, E

    2003-08-01

    We investigated environmental factors influencing the distribution of hookworm infection in KwaZulu-Natal, South Africa. Prevalence data were sourced from previous studies and additional surveys carried out to supplement the database. When geo-referenced the data revealed that higher prevalences are limited to areas below 150 m above sea level, and low prevalences to areas above this altitude. Using univariate analysis we investigated the differences in environmental factors in the two areas. The relationship between hookworm prevalence, altitude and climate-derived variables was assessed using Pearson correlation coefficient, and that of soil type using the t-test. Multivariate analysis was used to determine environmental factors that combine best to provide favourable conditions for hookworm distribution. The results revealed that areas 150 m above sea level, i.e. inland, supported low mean hookworm prevalences (x = 6, n = 21), and were characterized by soils with a clay content of more than 45%, variable temperatures and moderate rainfall. Hookworm prevalence also decreased southwards as temperatures became slightly cooler, rainfall remained more-or-less constant and the coastal plain narrowed. In the multivariate model prevalence was most significantly correlated with the mean daily minimum temperature for January followed by the mean number of rainy days for January. This indicates the importance of summer conditions in the transmission of hookworm infection in KwaZulu-Natal and suggests that transmission may be seasonal.

  6. Hookworm (Necator americanus) transmission in inland areas of sandy soils in KwaZulu-Natal, South Africa.

    PubMed

    Mabaso, M L H; Appleton, C C; Hughes, J C; Gouws, E

    2004-04-01

    This study extended the association between hookworm transmission in KwaZulu-Natal and the sandy coastal plain by investigating the parasite's occurrence in isolated areas of sandy soils further inland. A school-based prevalence survey was carried out in selected inland sandy areas and in surrounding areas dominated by clay soils within a narrow altitudinal range of between 500 and 700 m to reduce the effect of altitude on climate-related factors (rainfall and temperature). Sandy areas situated on the coastal plain were included in the analysis for comparative purposes. Soil samples (0-50 mm depth) were collected from each locality to assess their nematode loadings and to analyse selected physical and chemical properties. Significant differences were found between the moderate prevalence of hookworm infection among children living in inland areas with sandy soils (17.3%) and the low prevalence in surrounding non-sandy areas (5.3%, P < 0.001), and between infection among children living in all inland areas (9.3%) and the high prevalence on the coastal plain (62.5%, P < 0.001). Amounts of fine and medium sand were highest in both the coastal plain soils and in inland sandy areas and these fractions showed a significant positive correlation with hookworm prevalence and nematode loadings. Clay, coarse sand and organic matter contents were highest in surrounding non-sandy soils and showed a significant negative correlation with the nematode variables. No statistically significant correlations were found with soil pH at study localities. We conclude that properties of inland sandy soils, particularly particle size distribution, correlate well with hookworm prevalence and nematode loadings and therefore provide a more suitable habitat for nematodes than surrounding non-sandy areas. These results suggest that particle size distribution of sand fractions, organic matter and clay content in the soil influence the survival of hookworm larvae and hence the parasite's transmission.

  7. Preservation of bone mass and structure in hibernating black bears (Ursus americanus) through elevated expression of anabolic genes

    PubMed Central

    Goropashnaya, Anna V.; Tøien, Øivind; Stewart, Nathan C.; Chang, Celia; Wang, Haifang; Yan, Jun; Showe, Louise C.; Showe, Michael K.; Donahue, Seth W.; Barnes, Brian M.

    2015-01-01

    Physical inactivity reduces mechanical load on the skeleton, which leads to losses of bone mass and strength in non-hibernating mammalian species. Although bears are largely inactive during hibernation, they show no loss in bone mass and strength. To obtain insight into molecular mechanisms preventing disuse bone loss, we conducted a large-scale screen of transcriptional changes in trabecular bone comparing winter hibernating and summer non-hibernating black bears using a custom 12,800 probe cDNA microarray. A total of 241 genes were differentially expressed (P<0.01 and fold change >1.4) in the ilium bone of bears between winter and summer. The Gene Ontology and Gene Set Enrichment Analysis showed an elevated proportion in hibernating bears of overexpressed genes in six functional sets of genes involved in anabolic processes of tissue morphogenesis and development including skeletal development, cartilage development, and bone biosynthesis. Apoptosis genes demonstrated a tendency for downregulation during hibernation. No coordinated directional changes were detected for genes involved in bone resorption, although some genes responsible for osteoclast formation and differentiation (Ostf1, Rab9a, and c-Fos) were significantly underexpressed in bone of hibernating bears. Elevated expression of multiple anabolic genes without induction of bone resorption genes, and the down regulation of apoptosis-related genes, likely contribute to the adaptive mechanism that preserves bone mass and structure through prolonged periods of immobility during hibernation. PMID:22351243

  8. The Effect of Elevated CO2 on the Growth and Food Consumption of Juvenile Winter Flounder Pseudopleuronectes Americanus

    EPA Science Inventory

    Increasing levels of atmospheric carbon dioxide are causing changes in seawater chemistry in the world’s oceans. In estuarine waters, atmospheric CO2 exacerbates already declining pH due to high productivity and respiration caused by cultural eutrophication. These two sources o...

  9. Annual changes in serum sex steroids in male and female black (Ursus americanus) and polar (Ursus maritimus) bears.

    PubMed

    Palmer, S S; Nelson, R A; Ramsay, M A; Stirling, I; Bahr, J M

    1988-06-01

    The adaptation of black and polar bears to their environments is proportional to the severity of climate and food restriction. Both black and polar bears mate during the spring, despite differences in their recent metabolic state. Reproductive activity in black bears follows 4 mo of torpor, whereas reproduction in polar bears occurs prior to torpor. The goals of this study were to measure the annual changes in serum sex steroids in male and female black and polar bears, and to determine if changes in serum levels of these steroids were associated with metabolic condition or photoperiod. Serum testosterone (T) concentrations were elevated during spring in black and polar bears. Moreover, this increase in serum T in polar bears during spring was correlated with age and testis size. Serum progesterone (P4) concentrations increased in pregnant polar bears in fall coincident with the time of expected implantation. No increases in serum P4 were observed in nonpregnant black and polar bears. Serum estradiol (E2) was elevated in nonpregnant and pregnant polar bears 2 mo prior to the time of expected implantation. We found that serum sex steroids measured in black and polar bears change independent of torpor. Therefore, our results suggest that photoperiod may be a more important regulator of serum steroid levels and reproduction than metabolic condition.

  10. Biomarker Analysis of American Toad (Anaxyrus Americanus) and Grey Tree Frog (Hyla Versicolor) Tadpoles Following Exposure to Atrazine

    EPA Science Inventory

    To better understand the mode of action of atrazine in amphibians, we utilized mass spectrometry-based metabolomics to investigate the biochemical changes in two species of larval amphibians exposed to atrazine. Our objectives were to 1) Use changes in endogenous metabolites to f...

  11. Biomarker Analysis of American Toad (Anaxyrus Americanus) and Grey Tree Frog (Hyla Versicolor) Tadpoles Following Exposure to Atrazine

    EPA Science Inventory

    To better understand the mode of action of atrazine in amphibians, we utilized mass spectrometry-based metabolomics to investigate the biochemical changes in two species of larval amphibians exposed to atrazine. Our objectives were to 1) Use changes in endogenous metabolites to f...

  12. Seroepidemiologic study on the prevalence of Toxoplasma gondii and Trichinella spp. infections in black bears (Ursus americanus) in Pennsylvania, USA

    USDA-ARS?s Scientific Manuscript database

    The protozoan Toxoplasma gondii and the metazoan Trichinella spp. infect virtually all warm-blooded animals, including birds, humans, livestock, and marine mammals. Both parasitic infections can cause serious illness in human beings and can be acquired by ingesting under-cooked meat harbouring infec...

  13. PERCEPTION OF THE MOLTING HORMONE 20-HYDROXECDYSONE BY HOMARUS AMERICANUS: LOCALIZATION OF STEROID RECEPTORS AND EFFECT ON BEHAVIOR

    EPA Science Inventory

    There is growing evidence that hormones, when released from an animal into the environment, act as chemical signals to other organisms. There is also evidence to suggest that hormones are released by lobsters during sexual and agonistic encounters to signal conspecifics. The go...

  14. Aerococcus viridans var. homari: The presence of capsule and the relationship to virulence in American lobster (Homarus americanus).

    PubMed

    Clark, K Fraser; Wadowska, Dorota; Greenwood, Spencer J

    2016-01-01

    The relationship between virulence and encapsulation of Aerococcus viridans var. homari was evaluated by growing virulent (Rabin's) and avirulent (ATCC 10400) strains under varying culture conditions, and during challenge trials. Changes in capsule thickness were monitored using a modified lysine-ruthenium red (LRR) fixation method and transmission electron microscopy. The virulent Rabin's strain possessed a prominent capsule of 0.252 μm±0.061 μm that was diminished by in vitro growth conditions to 0.206 μm±0.076 μm. The ATCC 10400 strain capsule thickness decreased from 0.157 μm±0.043 μm to 0.117 μm±0.043 μm after 10 in vitro passages. The virulent Rabin's strain capsule was significantly thicker than the avirulent ATCC 10400 strain under all growth conditions. Rabin's strain, regardless of pre-challenge growth conditions or dose (high dose 10(7) or low dose 10(2)), was able to kill lobsters in 7 days at 15°C. ATCC 10400 strain, regardless of pre-challenge growth conditions, killed lobster only at high doses (10(7)) with varying median time to death of ∼15 days, while at low doses (10(2)) all lobsters survived and no bacteria were present after 42 days. This work demonstrates the importance of the thickness of the A. viridans capsule to virulence in the American lobster.

  15. Seascape genomics provides evidence for thermal adaptation and current-mediated population structure in American lobster (Homarus americanus).

    PubMed

    Benestan, Laura; Quinn, Brady K; Maaroufi, Halim; Laporte, Martin; Clark, Fraser K; Greenwood, Spencer J; Rochette, Rémy; Bernatchez, Louis

    2016-10-01

    Investigating how environmental features shape the genetic structure of populations is crucial for understanding how they are potentially adapted to their habitats, as well as for sound management. In this study, we assessed the relative importance of spatial distribution, ocean currents and sea surface temperature (SST) on patterns of putatively neutral and adaptive genetic variation among American lobster from 19 locations using population differentiation (PD) approaches combined with environmental association (EA) analyses. First, PD approaches (using bayescan, arlequin and outflank) found 28 outlier SNPs putatively under divergent selection and 9770 neutral SNPs in common. Redundancy analysis revealed that spatial distribution, ocean current-mediated larval connectivity and SST explained 31.7% of the neutral genetic differentiation, with ocean currents driving the majority of this relationship (21.0%). After removing the influence of spatial distribution, no SST were significant for putatively neutral genetic variation whereas minimum annual SST still had a significant impact and explained 8.1% of the putatively adaptive genetic variation. Second, EA analyses (using Pearson correlation tests, bayescenv and lfmm) jointly identified seven SNPs as candidates for thermal adaptation. Covariation at these SNPs was assessed with a spatial multivariate analysis that highlighted a significant temperature association, after accounting for the influence of spatial distribution. Among the 505 candidate SNPs detected by at least one of the three approaches, we discovered three polymorphisms located in genes previously shown to play a role in thermal adaptation. Our results have implications for the management of the American lobster and provide a foundation on which to predict how this species will cope with climate change.

  16. Ecdysteroid receptor from the American lobster Homarus americanus: EcR/RXR isoform cloning and ligand-binding properties.

    PubMed

    Tarrant, Ann M; Behrendt, Lars; Stegeman, John J; Verslycke, Tim

    2011-09-01

    In arthropods, ecdysteroids regulate molting by activating a heterodimer formed by the ecdysone receptor (EcR) and retinoid X receptor (RXR). While this mechanism is similar in insects and crustaceans, variation in receptor splicing, dimerization and ligand affinity adds specificity to molting processes. This study reports the EcR and RXR sequences from American lobster, a commercially and ecologically important crustacean. We cloned two EcR splice variants, both of which specifically bind ponasterone A, and two RXR variants, both of which enhance binding of ponasterone A to the EcR. Lobster EcR has high affinity for ponasterone A and muristerone and moderately high affinity for the insecticide tebufenozide. Bisphenol A, diethyl phthalate, and two polychlorinated biphenyls (PCB 29 and PCB 30), environmental chemicals shown to interfere with crustacean molting, showed little or no affinity for lobster EcR. These studies establish the molecular basis for investigation of lobster ecdysteroid signaling and signal disruption by environmental chemicals.

  17. CHARACTERIZATION OF A BASOLATERAL ELECTRONEUTRAL NA+/H+ ANTIPORTER IN ATLANTIC LOBSTER (HOMARUS AMERICANUS) HEPATOPANCREATIC EPITHELIAL VESICLES. (R823068)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  18. ORGANIC CONTAMINANT DISTRIBUTION IN SEDIMENTS, POLYCHAETES (NEREIS VIRENS) AND THE AMERICAN LOBSTER, HOMARUS AMERICANUS IN A LABORATORY FOOD CHAIN EXPERIMENT

    EPA Science Inventory

    A laboratory experiment was conducted to investigate the transfer of organic contaminants from an environmentally contaminated marine sediment through a simple marine food chain. The infaunal polychaete, Nereis virens, was exposed to contaminated sediment collected from the Passa...

  19. ELEMENTAL AND ISOTPOIC FINGERPRINTS OF JUVENILE WINTER FLOUNDER (PLEURONECTES AMERICANUS) FROM NARRAGANSETT BAY, RI (USA) AND SURROUNDING COASTAL PONDS

    EPA Science Inventory

    Elemental fingerprinting has become a powerful tool in fisheries science for identifying fish migration patterns, seasonal changes in habitat use, and for delineating the nursery origins of adult fish populations. In this study, we investigated whether elemental and isotopic sign...

  20. Long-term assessment of settlement and growth of juvenile winter flounder ( Pseudopleuronectes americanus) in New Jersey estuaries

    NASA Astrophysics Data System (ADS)

    Sogard, Susan M.; Able, Kenneth W.; Hagan, Stacy M.

    2001-06-01

    We examined patterns of metamorphosis, settlement, and growth for young-of-the-year winter flounder over a ten year period (1990-1999) in four estuaries spanning the coast of New Jersey, USA, with the objective to determine the spatial and temporal coherence in these processes. We hypothesised that these processes could be influenced by large-scale climatic factors such as temperature and small-scale, local factors such as predator and prey abundances and differences associated with the localised population structure of winter flounder. Newly settled juveniles were collected in late May/early June each year. Increment counts on sagittal otoliths were used to determine the date of metamorphosis, and increment widths were used to estimate growth rates at two times, just after settlement and just prior to capture. A high level of consistency in spatial patterns among four individual estuaries was evident, and was largely driven by the northernmost site, Sandy Hook, which had higher fish densities and later metamorphosis than the three other sites, and faster growth rates than the two mid-coast sites (Barnegat Bay and Great Bay). In contrast to spatial patterns, consistent temporal patterns were evident only in the timing of metamorphosis, which was delayed in colder years at all sites. Weekly plankton sampling over the same ten year period at one site (Great Bay) yielded winter flounder larvae during a relatively narrow period in spring, with a later peak of abundance in colder years, in agreement with back-calculated dates of metamorphosis for settled juveniles. These patterns suggest that the timing of settlement is driven by large-scale climatic factors that influence the timing of spawning and/or larval development. Interannual variability in densities and growth rates, however, appeared to be independent at each site, indicating control by local environmental factors or genetic differences among local populations. The spatial consistency of growth rates suggests that appropriate nursery areas can be readily identified for juvenile winter flounder. However, subsequent recruitment needs to be verified at the level of local populations to identify contributing source habitats.

  1. A Relaxation Oscillator Description of the Burst-Generating Mechanism in the Cardiac Ganglion of the Lobster, Homarus americanus

    PubMed Central

    Mayeri, Earl

    1973-01-01

    Properties of the neural mechanism responsible for generating the periodic burst of spike potentials in the nine ganglion neurons were investigated by applying brief, single shocks to the four small cells with extracellular electrodes placed near the trigger zones of the small cells. The shock elicited a burst if presented during the latter portion of the silent period, terminated a burst during the latter portion of the burst period, and was followed by a newly initiated burst during the early portion of the burst period. The resultant changes in burst and silent period durations were quantitatively described by a second-order non-linear differential equation similar to the van der Pol equation for a relaxation oscillator. The equation also qualitatively described changes in firing threshold of the small cells during the burst cycle. The first derivative of the solution to the equation is similar to slow transmembrane potentials in neurons that are involved in generation of burst activity in other crustacean cardiac ganglia. PMID:19873681

  2. ORGANIC CONTAMINANT DISTRIBUTION IN SEDIMENTS, POLYCHAETES (NEREIS VIRENS) AND THE AMERICAN LOBSTER, HOMARUS AMERICANUS IN A LABORATORY FOOD CHAIN EXPERIMENT

    EPA Science Inventory

    A laboratory experiment was conducted to investigate the transfer of organic contaminants from an environmentally contaminated marine sediment through a simple marine food chain. The infaunal polychaete, Nereis virens, was exposed to contaminated sediment collected from the Passa...

  3. Inoculation of female American black bears (Ursus americanus) with partially purified porcine zona pellucidae limits cub production.

    PubMed

    Lane, V M; Liu, I K M; Casey, K; vanLeeuwen, E M G; Flanagan, D R; Murata, K; Munro, C

    2007-01-01

    The present 2-year study investigated the feasibility of using porcine zona pellucidae (pZP) as antigen for immunocontraception in American black bears. Sows, 3-6 years of age, were administered either two doses of 250 microg pZP with Freund's adjuvant (n = 10) or adjuvant alone (n = 5), one in April and one in May, and were kept away from the boars until June. Serum samples were collected before injections and before denning (November). The presence of sows with cubs at side was observed during premature emergence from denning. First-year results indicated that anti-pZP antibody titres in vaccinated sows were 2.5-9.0-fold (range) higher compared with non-vaccinated sows and that the vaccinated sows were threefold less likely to become pregnant (P = 0.167). Control and vaccinated bears produced 1.6 and 0.2 cubs per sow, respectively (P = 0.06). The second-year study investigated the feasibility of using pZP sequestered in a controlled-release pellet and a water-soluble adjuvant (QS-21) to avoid regulatory problems associated with Freund's adjuvant. Sows in the treatment group (n = 22) were administered a single dose of an emulsion of 250 microg pZP and 150 microg QS-21 plus a pellet containing 70-90 microg pZP for delayed release as booster dose. Control sows (n = 5) received the QS-21 adjuvant in pellet alone. Serum samples were collected before inoculations (April) and before denning (November). Seven cubs were born to the five control sows, but none was born to the 22 vaccinated sows (P < 0.001). Anti-pZP antibody mean absorbance ratios in control sows remained at background levels, whereas vaccinated sows had ratios fourfold higher than controls. Two-dimensional polyacrylamide gel electrophoresis and immunohistochemical localisation confirmed immunoreactivity of sera from inoculated bears. We conclude that cub production in the American black bear can be effectively limited with either two injections of 250 microg pZP or a single inoculation of partially purified pZP sequestered in controlled-release pellets.

  4. Spatial and Temporal Variability of Elemental Signautres in Juvenile Winter Flounder (Psuedopleuronectes americanus): Implications for Natal Connectivity

    EPA Science Inventory

    Elemental signatures in otoliths (fish ear-stones) have become a powerful tool in fisheries science for identifying fish migration patterns, reconstructing environmental histories, and for delineating the nursery origins of adult fish populations. Assessing connectivity between a...

  5. Mechanisms underlying the production of carapace vibrations and associated waterborne sounds in the American lobster, Homarus americanus.

    PubMed

    Henninger, Heidi Pye; Watson, Winsor H

    2005-09-01

    American lobsters produce carapace vibrations, which also lead to waterborne acoustic signals, by simultaneously contracting the antagonistic remotor and promotor muscles located at the base of the second antenna. These vibrations have a mean frequency of 183.1 Hz (range 87-261 Hz), range in duration from 68 to 1720 ms (mean 277.1 ms) and lead to waterborne sounds of similar frequencies. Lobsters most often produce these signals using only one pair of muscles at a time and alternate between the muscles of the left and right antennae when making a series of vibrations. Occasionally, they vibrate their carapace by simultaneously contracting both sets of muscles. While the remotor muscle is required for producing carapace vibrations, the promotor appears to play a secondary role. Electrical stimulation of the remotor, but not the promotor, results in the production of vibrations, while lesions of the remotor, but not promotor, eliminate the ability of lobsters to vibrate their carapace. Lobsters of all sizes and both sexes produce these signals when startled, grasped or threatened. However, at this time, the behavioral significance of vibration and/or sound production by American lobsters is not known.

  6. Winter flounder (Pseudopleuronectes americanus) estuarine habitat use and the association between spring temperature and subsequent year class strength

    NASA Astrophysics Data System (ADS)

    Wilber, Dara H.; Davis, David; Clarke, Douglas G.; Alcoba, Catherine J.; Gallo, Jenine

    2013-11-01

    Winter flounder habitat use in New York/New Jersey Harbor was examined through a long-term (2002-2010) bottom trawl sampling program (Aquatic Biological Survey) in which 5234 winter flounder were captured in 2069 samples collected at approximately 26 stations throughout the harbor. Interannual variability in catch-per-unit-effort (CPUE) primarily was attributable to fluctuations in Year-1 juvenile CPUE, which was positively correlated with total annual egg abundances from the previous year. Adult male CPUE during the spawning season was positively correlated with total egg abundances of the same year, whereas adult female CPUE was unrelated to annual egg abundances in the harbor. Annual variation in adult male densities in the harbor during the spawning season reflects the intensity of estuarine spawning activity, whereas adult female densities may include non-reproductive, foraging individuals. Seasonal fluctuations in condition indices reflected energy use during the spawning season, with relatively high condition in January, reduced levels in March and April, and elevated condition again in May. Adult CPUE peaked in April, coincident with the critical feeding period that follows spawning. Mean April water temperatures were positively correlated with egg abundances the following year and Year-1 juvenile CPUE two years later. A similar correlation between April temperatures and Year-1 juvenile abundances two years later was demonstrated using published data for winter flounder collected in Niantic Bay, CT. Higher April water temperatures may enhance benthic secondary production during the critical feeding period, and thus increase prey availability for foraging adults that need to restore energy reserves in order to reproduce the following year. A direct examination of benthic secondary production and variation in winter flounder estuarine foraging and subsequent spawning activity is needed to more fully understand this relationship.

  7. ELEMENTAL AND ISOTPOIC FINGERPRINTS OF JUVENILE WINTER FLOUNDER (PLEURONECTES AMERICANUS) FROM NARRAGANSETT BAY, RI (USA) AND SURROUNDING COASTAL PONDS

    EPA Science Inventory

    Elemental fingerprinting has become a powerful tool in fisheries science for identifying fish migration patterns, seasonal changes in habitat use, and for delineating the nursery origins of adult fish populations. In this study, we investigated whether elemental and isotopic sign...

  8. PERCEPTION OF THE MOLTING HORMONE 20-HYDROXECDYSONE BY HOMARUS AMERICANUS: LOCALIZATION OF STEROID RECEPTORS AND EFFECT ON BEHAVIOR

    EPA Science Inventory

    There is growing evidence that hormones, when released from an animal into the environment, act as chemical signals to other organisms. There is also evidence to suggest that hormones are released by lobsters during sexual and agonistic encounters to signal conspecifics. The go...

  9. CHARACTERIZATION OF A BASOLATERAL ELECTRONEUTRAL NA+/H+ ANTIPORTER IN ATLANTIC LOBSTER (HOMARUS AMERICANUS) HEPATOPANCREATIC EPITHELIAL VESICLES. (R823068)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  10. Related neuropeptides use different balances of unitary mechanisms to modulate the cardiac neuromuscular system in the American lobster, Homarus americanus.

    PubMed

    Dickinson, Patsy S; Calkins, Andrew; Stevens, Jake S

    2015-02-01

    To produce flexible outputs, neural networks controlling rhythmic motor behaviors can be modulated at multiple levels, including the pattern generator itself, sensory feedback, and the response of the muscle to a given pattern of motor output. We examined the role of two related neuropeptides, GYSDRNYLRFamide (GYS) and SGRNFLRFamide (SGRN), in modulating the neurogenic lobster heartbeat, which is controlled by the cardiac ganglion (CG). When perfused though an isolated whole heart at low concentrations, both peptides elicited increases in contraction amplitude and frequency. At higher concentrations, both peptides continued to elicit increases in contraction amplitude, but GYS caused a decrease in contraction frequency, while SGRN did not alter frequency. To determine the sites at which these peptides induce their effects, we examined the effects of the peptides on the periphery and on the isolated CG. When we removed the CG and stimulated the motor nerve with constant bursts of stimuli, both GYS and SGRN increased contraction amplitude, indicating that each peptide modulates the muscle or the neuromuscular junction. When applied to the isolated CG, neither peptide altered burst frequency at low peptide concentrations; at higher concentrations, SGRN decreased burst frequency, whereas GYS continued to have no effect on frequency. Together, these data suggest that the two peptides elicit some of their effects using different mechanisms; in particular, given the known feedback pathways within this system, the importance of the negative (nitric oxide) relative to the positive (stretch) feedback pathways may differ in the presence of the two peptides.

  11. The presence of tyramine and related monoamines in the nerve cord and some other tissues of the lobster, Homarus americanus.

    PubMed

    Juorio, A V; Sloley, B D

    1988-03-22

    This report shows the existence of endogenous p-tyramine in the nerve cord and some organs of the lobster. Their concentrations are lower than those of dopamine or 5-hydroxytryptamine. The nerve cord levels of m-tyramine, beta-phenylethylamine and tryptamine are much lower than those of the phenolic or catecholic amines. The finding that the administration of an aromatic-L-amino acid decarboxylase inhibitor leads to a decrease of p-tyramine gives further evidence that this amine is synthesized from p-tyrosine, which is also found in high concentrations in the lobster nerve cord. The widespread distribution of p-tyramine in the nervous system and peripheral tissues of the lobster suggests that this amine may have additional roles rather than functioning only as a precursor of p-octopamine.

  12. Related neuropeptides use different balances of unitary mechanisms to modulate the cardiac neuromuscular system in the American lobster, Homarus americanus

    PubMed Central

    Calkins, Andrew; Stevens, Jake S.

    2014-01-01

    To produce flexible outputs, neural networks controlling rhythmic motor behaviors can be modulated at multiple levels, including the pattern generator itself, sensory feedback, and the response of the muscle to a given pattern of motor output. We examined the role of two related neuropeptides, GYSDRNYLRFamide (GYS) and SGRNFLRFamide (SGRN), in modulating the neurogenic lobster heartbeat, which is controlled by the cardiac ganglion (CG). When perfused though an isolated whole heart at low concentrations, both peptides elicited increases in contraction amplitude and frequency. At higher concentrations, both peptides continued to elicit increases in contraction amplitude, but GYS caused a decrease in contraction frequency, while SGRN did not alter frequency. To determine the sites at which these peptides induce their effects, we examined the effects of the peptides on the periphery and on the isolated CG. When we removed the CG and stimulated the motor nerve with constant bursts of stimuli, both GYS and SGRN increased contraction amplitude, indicating that each peptide modulates the muscle or the neuromuscular junction. When applied to the isolated CG, neither peptide altered burst frequency at low peptide concentrations; at higher concentrations, SGRN decreased burst frequency, whereas GYS continued to have no effect on frequency. Together, these data suggest that the two peptides elicit some of their effects using different mechanisms; in particular, given the known feedback pathways within this system, the importance of the negative (nitric oxide) relative to the positive (stretch) feedback pathways may differ in the presence of the two peptides. PMID:25392168

  13. Spatial and Temporal Variability of Elemental Signautres in Juvenile Winter Flounder (Psuedopleuronectes americanus): Implications for Natal Connectivity

    EPA Science Inventory

    Elemental signatures in otoliths (fish ear-stones) have become a powerful tool in fisheries science for identifying fish migration patterns, reconstructing environmental histories, and for delineating the nursery origins of adult fish populations. Assessing connectivity between a...

  14. Birds of the Kilbuck and Ahklun mountain region, Alaska

    USGS Publications Warehouse

    Petersen, Margaret R.; Weir, Douglas N.; Dick, Matthew H.

    1991-01-01

    also provide further information on distributions or documentation of unusual occurrences for nine taxa (frigatebird, Fregata spp.; Baikal teal, Anas formosa; American kestrel, Falco sparverius; Terek sandpiper, Xenus cinereus; bristle-thighed curlew, Numenius tahitiensis; slaty-backed gull, Larus schistisagus; rufous hummingbird, Selasphorus rufus; song sparrow, Melospiza melodia; and red-winged blackbird, Agelaius phoeniceus). We provide quantitative data on the coastal migration of 11 species along Bristol Bay (red-throated loon, Gavia stellata; Pacific loon, Gavia pacifica; pelagic cormorant, Phalacrocorax pelagicus; emperor goose, Chen canagica; brant; Steller's eider, Polysticta stellen; common eider, Somateria mollissima; king eider; black scoter, Melanina nigra; white-winged scoter, Melanina fusca; and surf scoter, Melanina perspicillatd). We document changes in nesting densities, differences in numbers, or habitat variations of 32 species in response to human activities (e.g., semipalmated plover, Charadrius semipalmatus; arctic tern, Sterna paradisaea; tree swallow, Tachycineta bicolor, varied thrush, Ixoreus naevius; yellow-rumped warbler, Dendroica coronata; and American tree sparrow, Spizella arborea). We report the changes in a major colony of Aleutian terns (Sterna aleatico) at irregular intervals over 50 years.

  15. 78 FR 48137 - Notice of Petitions by Firms for Determination of Eligibility To Apply for Trade Adjustment...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-07

    .... Precision Optics, Inc 33 Curlew Street, 7/31/2013 The firm manufacturers Rochester, NY 14606. rotational and prismatic components used in optics, medical, defense, electrical, microwave and aerospace industries. Any...

  16. Translating Latin American/US Latina frameworks and methods in gender and health equity: linking women's health education and participatory social change.

    PubMed

    Shapiro, Ester R

    This article applies transdisciplinary approaches to critical health education for gender equity by analyzing textual and political strategies translating/culturally adapting the U.S. feminist health text, Our Bodies Ourselves (OBOS), for Latin American/Caribbean and U.S. Latina women. The resulting text, Nuestros Cuerpos, Nuestras Vidas (NCNV), was revised at multiple levels to reflect different cultural\\sociopolitical assumptions connecting individual knowledge, community-based and transnational activist organizations, and strategic social change. Translation/cultural adaptation decisions were designed to ensure that gender-equitable health promotion education crossed cultural borders, conveying personal knowledge and motivating individual actions while also inspiring participation in partnerships for change. Transdisciplinary approaches integrating critical ecosystemic frameworks and participatory methods can help design health promotion education mobilizing engaged, gender-equitable health citizenship supporting both personal and societal change.

  17. Seasonal regulation of the growth hormone-insulin-like growth factor-I axis in the American black bear (Ursus americanus).

    PubMed

    Blumenthal, Stanley; Morgan-Boyd, Rebecca; Nelson, Ralph; Garshelis, David L; Turyk, Mary E; Unterman, Terry

    2011-10-01

    The American black bear maintains lean body mass for months without food during winter denning. We asked whether changes in the growth hormone/insulin-like growth factor-I (GH-IGF-I) axis may contribute to this remarkable adaptation to starvation. Serum IGF-I levels were measured by radioimmunoassay, and IGF-binding proteins (IGFBPs) were analyzed by ligand blotting. Initial studies in bears living in the wild showed that IGF-I levels are highest in summer and lowest in early winter denning. Detailed studies in captive bears showed that IGF-I levels decline in autumn when bears are hyperphagic, continue to decline in early denning, and later rise above predenning levels despite continued starvation in the den. IGFBP-2 increased and IGFBP-3 decreased in early denning, and these changes were also reversed in later denning. Treatment with GH (0.1 mg·kg(-1)·day(-1) × 6 days) during early denning increased serum levels of IGF-I and IGFBP-3 and lowered levels of IGFBP-2, indicating that denning bears remain responsive to GH. GH treatment lowered blood urea nitrogen levels, reflecting effects on protein metabolism. GH also accelerated weight loss and markedly increased serum levels of free fatty acids and β-hydroxybutyrate, resulting in a ketoacidosis (bicarbonate decreased to 15 meq/l), which was reversed when GH was withdrawn. These results demonstrate seasonal regulation of GH/IGF-I axis activity in black bears. Diminished GH activity may promote fat storage in autumn in preparation for denning and prevent excessive mobilization and premature exhaustion of fat stores in early denning, whereas restoration of GH/IGF activity in later denning may prepare the bear for normal activity outside the den.

  18. The metabolism of polycyclic aromatic hydrocarbons by two marine fishes: the little skate, Raja erinacea and the winter flounder, Pseudopleuronectes americanus

    SciTech Connect

    Foureman, G.L.

    1982-01-01

    Hepatic cytosolic fractions from male little skates exhibited high specific rates of enzymatic conjugation of glutathione with the polycyclic aromatic hydrocarbon (PAH) oxide, benzo(a)pyrene 4,5-oxide (4,5-BPO). High performance liquid chromatography analysis demonstrated that all hepatic skate tranferases showed strict configurational stereoselectivity for the R carbons in enantiomeric 4,5-BPO, only the S products were observed in enzymic reaction mixtures. Rates of metabolism of the PAH benzo(a)pyrene (i.e., AHH activity) varied markedly in hepatic homogenates prepared from feral winter flounder caught in the Gulf of Maine. Treatment of feral flounder with either a PAH or a PAH-type compound resulted in induced AHH activities in the liver of all flounder so treated. ANF (7,8-benzoflavone) acted to inhibit the hepatic AHH activity in all treated fish as it did in 64% of the feral flounder examined. Electrophoretic analysis of hepatic microsomes from flounder treated with either a PAH or a PAH-type compound showed a novel or enriched polypeptide species at approximately 57,000 MW. A polypeptide species of similar MW was only faintly discernable in hepatic microsomes from feral flounder whose hepatic AHH activities were much lower than that of the treated flounder whereas a band of similar molecular weight was prominent in hepatic microsomes from feral flounder with high hepatic AHH activities. These results suggest that many of the flounder in this area of Maine have induction of their hepatic monooxygenase systems similar to that caused by PAH or PAH-type compounds.

  19. Computed tomographic, magnetic resonance imaging, and cross-sectional anatomic features of the manus in a normal American black bear (Ursus americanus).

    PubMed

    Ober, C P; Freeman, L E

    2010-06-01

    The purpose of this study was to provide a detailed description of cross-sectional anatomic structures of the manus of a black bear cadaver and correlate anatomic findings with corresponding features in computed tomographic (CT) and magnetic resonance (MR) images. CT, MR imaging, and transverse sectioning were performed on the thoracic limb of a cadaver female black bear which had no evidence of lameness or thoracic limb abnormality prior to death. Features in CT and MR images corresponding to clinically important anatomic structures in anatomic sections were identified. Most of the structures identified in transverse anatomic sections were also identified using CT and MR imaging. Bones, muscles and tendons were generally easily identified with both imaging modalities, although divisions between adjacent muscles were rarely visible with CT and only visible sometimes with MR imaging. Vascular structures could not be identified with either imaging modality.

  20. Effects of intratesticular zinc gluconate treatment on testicular dimensions, echodensity, histology, sperm production, and testosterone secretion in American black bears (Ursus americanus).

    PubMed

    Brito, Leonardo F C; Sertich, Patricia L; Rives, William; Knobbe, Marc; Del Piero, Fabio; Stull, Gordon B

    2011-05-01

    Eight adult American black bears were used to evaluate the effects of chemical castration by intratesticular zinc gluconate treatment on testicular dimensions, echodensity, histology, sperm production, and testosterone secretion. Treatment did not affect testicular dimensions and did not result in decreased resting or GnRH-stimulated testosterone secretion. Multifocal hyperchoic areas in the testicular parenchyma were observed on ultrasound examination, and white foci were observed on gross pathology examination after zinc gluconate treatment. Histologically, there were normal seminiferous tubules containing either round or elongated spermatids, along with abnormal tubules in all bears after treatment. Vacuolation of the seminiferous epithelium, sloughing of germ cells into the tubules' lumen, presence of multinuclear giant cells, and reduced height of the seminiferous epithelium with missing generations of germ cells were commonly observed. The most severe testicular changes were multifocal and included fibrosis, complete degeneration of the seminiferous epithelium with shrinkage of the tubule, and sperm stasis. Epididymal sperm reserve was 982.74 ± 654.16 × 10(6) sperm (mean ± SEM) and motile sperm were observed in the epididymis of all but one of the bears. In conclusion, although intratesticular zinc gluconate treatment in black bears resulted in testicular degenerative changes detected by ultrasound and histology examinations, sperm production was not completely ablated. We inferred that normal fertility might have been compromised, but treatment unlikely resulted in sterility. Copyright © 2011. Published by Elsevier Inc.

  1. Real-time PCR assay for Aquimarina macrocephali subsp. homaria and its distribution in shell disease lesions of Homarus americanus, Milne-Edwards, 1837, and environmental samples.

    PubMed

    Quinn, Robert A; Hazra, Suchandra; Smolowitz, Roxanna; Chistoserdov, Andrei Y

    2017-04-03

    Epizootic shell disease (ESD) is causing major losses to the lobster fishery in southern New England. Potential pathogens have been identified in lesion communities, but there are currently no efficient means of detecting and quantifying their presence. A qPCR assay was developed for a key potential pathogen, Aquimarina macrocephali subsp. homaria found to be ubiquitous in ESD lesions but not the unaffected integument. Application of the assay to various samples demonstrated that A. macrocephali subsp. homaria is ubiquitous and abundant in lobster lesions, commonly associated with healthy surfaces of crabs and is scarce in water and sediment samples from southern New England suggesting the affinity of this microorganism to the Arthropod integument. The qPCR assay developed here can be applied in future in vivo and in vitro studies to better understand the ecology and role in shell disease of A. 'homaria'.

  2. PHORBOL ESTER ACTIVATION OF AN NHE-LIKE ELECTRONEUTRAL NA+/H+ ANTIPORTER IN ISOLATED E-CELLS OF LOBSTER (HOMARUS AMERICANUS) HEPATOPANCREAS. (R823068)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  3. COPPER TRANSPORT BY ISOLATED AND PURIFIED DISTINCT CELL POPULATIONS OF THE LOBSTER (HOMARUS AMERICANUS) HEPATOPANCREAS USING A FLUOROMETRIC DYE. (R823068)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  4. Effects of Sediment Nitrogen Availability and Plant Density on Interactions Between the Growth of Hydrilla Verticillata and Potamogeton Americanus. Aquatic Plant Control Research Program.

    DTIC Science & Technology

    1991-12-01

    fractions. Suppression coefficients for each species were calculated to summarize competitive effects in mixtures relative to grow*.h of plants alone...11 4 Discussion Responses to Density A long-standing criticism of plant competition experiments has been the use of a single initial plant density... competitive superiority may be more sensitive than others to initial plant density (for review, see Rousch et al. 1989). However, initial plant density

  5. The effects of fin rot disease and sampling method on blood chemistry and hematocrit measurements of winter flounder, Pseudopleuronectes americanus from New Haven Harbor (1987--1990).

    PubMed

    Ziskowski, J; Mercaldo-Allen, R; Pereira, J J; Kuropat, C; Goldberg, R

    2008-04-01

    Winter flounder from New Haven, Connecticut were evaluated for fin rot disease. Blood samples collected from healthy and diseased fish were used to measure bilirubin, calcium, hematocrit, inorganic phosphorus, osmolality, and total protein. Blood measurements were significantly affected by the presence of fin rot disease and by sampling mode (bled immediately or after 18 h). A reduction in blood chemistry values was associated with fin rot disease. Logistic regression modeling was used to identify explanatory variables contributing to the fin rot outcome in winter flounder. Blood constituent levels were higher in fish bled immediately versus 18 h post-capture, especially among fish without fin rot, suggesting that a waiting period is necessary for blood values to stabilize following initial sampling stress. This study presents evidence that winter flounder blood chemistry and hematocrit measurements are affected by fin rot disease.

  6. COPPER TRANSPORT BY ISOLATED AND PURIFIED DISTINCT CELL POPULATIONS OF THE LOBSTER (HOMARUS AMERICANUS) HEPATOPANCREAS USING A FLUOROMETRIC DYE. (R823068)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  7. PHORBOL ESTER ACTIVATION OF AN NHE-LIKE ELECTRONEUTRAL NA+/H+ ANTIPORTER IN ISOLATED E-CELLS OF LOBSTER (HOMARUS AMERICANUS) HEPATOPANCREAS. (R823068)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  8. Thallium, uranium, and {sup 235}U/{sup 238}U ratios in the digestive gland of American lobster (Homarus americanus) from an industrialized harbor

    SciTech Connect

    Chou, C.L.; Uthe, J.F.

    1995-01-01

    Only a few studies have concentrated on elements such as thallium (TI). Uranium (U) has been studied as a radionuclide of concern in food and the environment. Foodstuffs contain 10-100 ng U{center_dot}{sup -1} with vegetables and cereals contributing most heavily to the daily intake of ca 1.5 ug U. Between 10-30% of ingested U is absorbed, with most being stored in bone. Rainbow trout (onchorynchus mykiss) and longnose sucker (Catostomus catostomus) from a lake with naturally high radioactivity contained < 5 ng U{center_dot}g{sup -1} in the flesh. Trout bone contained 40 ng U{center_dot}g{sup -1}. Higher tissue U concentrations occurred in fish from areas receiving U mining wastes. Bioconcentration factors for bone and flesh were estimated to be low, 118 and 14.7, respectively. This paper describes the Inductively coupled plasma-mass spectrometry (ICP-MS) determination of Tl and U in digestive gland tissue from lobsters captured in the vicinity of Belledune Harbor, New Brunswick, Canada. The harbor is the site of a lead smelter, a fertilizer plant, and a coal-fired power station (the latter due to enter production in late 1993) and thus has the potential of adding significant amounts of Tl to the local marine environment. The accumulation of Tl from water by marine shellfish is low, at least for bivalves, and the accumulated Tl is eliminated in a number of days when the animals are transferred to clean water. Bioconcentration factors for U in finfish ranged from 0.4-17 for larger species. However, because of the high concentrations of various trace elements in lobster digestive gland, its desirability as a foodstuff, and its relatively large size (approximately 20% of the edible tissue yield), we have investigated Tl and U concentrations and {sup 235U}/{sup 238U} ratios in it. 15 refs., 1 fig., 3 tabs.

  9. Influence of gonadotropic hormone-releasing hormone analog (GnRH-A) on plasma sex steroid profiles and milt production in male winter flounder, Pseudopleuronectes americanus (Walbaum).

    PubMed

    Harmin, S A; Crim, L W

    1993-03-01

    The effects of gonadotropic hormone-releasing hormone analog (GnRH-A) treatment on the onset and duration of increases in plasma sex steroids and milt production (milt volume and number of spermatozoa) were investigated in prespawning male winter flounder. After treatment of maturing males during the winter with a single injection of either 20 or 200 μg/kg [D-Ala(6), Pro(9)-NHEt]LHRH (GnRH-A), plasma levels of testosterone and 11-ketotestosterone were increased within 12h and the steroid hormone levels remained elevated for long periods lasting several days. The androgenic steroid response of males was delayed after the administration of a lower dose of GnRH-A (2 μg/kg). Although a single GnRH-A injection in December or January advanced the onset of spermiation in some males, only small amounts (<50 μl) of milt could be collected. By March, all males were in spermiating condition following GnRH-A treatment; however, significant increases in sperm production, particularly increases in milt volume, occurred in fish twice treated with GnRH-A.

  10. Isolation and genetic characterization of Toxoplasma gondii from black bears (Ursus americanus), bobcats (Felis rufus), and feral cats (Felis catus) from Pennsylvania

    USDA-ARS?s Scientific Manuscript database

    Toxoplasma gondii infects virtually all warm-blooded hosts worldwide. Recently, attention has been focused on the genetic diversity of the parasite to explain its pathogenicity in different hosts. It has been hypothesized that interaction between feral and domestic cycles of T. gondii may increase u...

  11. Fine-mapping and identification of a candidate gene underlying the d2 dwarfing phenotype in pearl millet, Cenchrus americanus (L.) Morrone.

    PubMed

    Parvathaneni, Rajiv K; Jakkula, Vinod; Padi, Francis K; Faure, Sebastien; Nagarajappa, Nethra; Pontaroli, Ana C; Wu, Xiaomei; Bennetzen, Jeffrey L; Devos, Katrien M

    2013-03-01

    Pearl millet is one of the most important subsistence crops grown in India and sub-Saharan Africa. In many cereal crops, reduced height is a key trait for enhancing yield, and dwarf mutants have been extensively used in breeding to reduce yield loss due to lodging under intense management. In pearl millet, the recessive d2 dwarfing gene has been deployed widely in commercial germplasm grown in India, the United States, and Australia. Despite its importance, very little research has gone into determining the identity of the d2 gene. We used comparative information, genetic mapping in two F2 populations representing a total of some 1500 progeny, and haplotype analysis of three tall and three dwarf inbred lines to delineate the d2 region by two genetic markers that, in sorghum, define a region of 410 kb with 40 annotated genes. One of the sorghum genes annotated within this region is ABCB1, which encodes a P-glycoprotein involved in auxin transport. This gene had previously been shown to underlie the economically important dw3 dwarf mutation in sorghum. The cosegregation of ABCB1 with the d2 phenotype, its differential expression in the tall inbred ICMP 451 and the dwarf inbred Tift 23DB, and the similar phenotype of stacked lower internodes in the sorghum dw3 and pearl millet d2 mutants suggest that ABCB1 is a likely candidate for d2.

  12. Latitudinal and stock-specific variation in size- and age-at-maturity of female winter flounder, Pseudopleuronectes americanus, as determined with gonad histology

    NASA Astrophysics Data System (ADS)

    McBride, Richard S.; Wuenschel, Mark J.; Nitschke, Paul; Thornton, Grace; King, Jeremy R.

    2013-01-01

    Female winter flounder were examined using gonad histology to determine the adequacy of routine macroscopic maturity classification methods and to determine the spatial variation in size and age of maturity in U.S. waters. Sampling occurred in spring and autumn, which was adequate to collect immature, mature, spawning-active, and non-active females. Females were collected in coastal waters from Delaware Bay, USA, to the Scotian Shelf, Canada, including in Long Island Sound and on Georges Bank, which covered all U.S. stock areas. Mature fish spawned in spring, when gonads comprised up to 30% of the total body weight. Direct comparisons of maturity assignment by macroscopic versus microscopic methods demonstrated that both schemes are compatible, but the more cost-effective macroscopic method had trouble distinguishing larger immature from smaller resting females. Spatial comparisons, using gonad histology only, supported the existence of three stocks in U.S. waters, but also revealed significant variation in age at maturity within the two coastal stocks. Age-at-maturity was more variable than size-at-maturity, which is consistent with known stock-specific patterns of growth rates and a postulated life history tradeoff to delay maturity until a size threshold is reached. The within-stock variation in median age at maturity, about one year for coastal stocks, recommends further investigation of using static, stock-specific maturity ogives to calculate reference points for management.

  13. /sup 32/P-postlabeling analysis of DNA adducts in liver of wild English sole (Parophrys vetulus) and winter flounder (Pseudopleuronectes americanus)

    SciTech Connect

    Varanasi, U.; Reichert, W.L.; Stein, J.E.

    1989-03-01

    The 1-butanol adduct enhancement version of the 32P-postlabeling assay was used to measure the levels of hepatic DNA adducts in the marine flatfish, English sole (Parophrys vetulus), sampled from the Duwamish Waterway and Eagle Harbor, Puget Sound, WA, where they are exposed to high concentrations of sediment-associated chemical contaminants and exhibit an elevated prevalence of hepatic neoplasms. Hepatic DNA was also analyzed from English sole from a reference area (Useless Bay, WA) and from reference English sole treated with organic-solvent extracts of sediments from the two contaminated sites. Autoradiograms of thin-layer chromatograms of 32P-labeled hepatic DNA digests from English sole from the contaminated sites exhibited up to three diagonal radioactive zones, which were not present in autoradiograms of thin-layer chromatogram maps of 32P-labeled DNA digests from English sole from the reference site. These diagonal radioactive zones contained several distinct spots as well as what appeared to be multiple overlapping adduct spots. The levels (nmol of adducts/mol of nucleotides) of total DNA adducts for English sole from Duwamish Waterway and Eagle Harbor were 26 +/- 28 (DS) and 17 +/- 9.6, respectively. All autoradiograms of DNA from fish from the contaminated sites exhibited a diagonal radioactive zone where DNA adducts of chrysene, benzo(a)pyrene, and dibenz(a,h)anthracene, formed in vitro using English sole hepatic microsomes, were shown to chromatograph. English sole treated with extracts of the contaminated sediments had adduct profiles generally similar to those for English sole from the respective contaminated sites.

  14. Fiber polymorphism in skeletal muscles of the American lobster, Homarus americanus: continuum between slow-twitch (S1) and slow-tonic (S2) fibers.

    PubMed

    Medler, Scott; Lilley, Travis; Mykles, Donald L

    2004-07-01

    In recent years, an increasing number of studies has reported the existence of single fibers expressing more than one myosin heavy chain (MHC) isoform at the level of fiber proteins and/or mRNA. These mixed phenotype fibers, often termed hybrid fibers, are currently being recognized as the predominant fiber type in many muscles, and the implications of these findings are currently a topic of great interest. In a recent study, we reported single fibers from the cutter claw closer muscle of lobsters that demonstrated a gradation between the slow-twitch (S1) and slow-tonic (S2) muscle phenotype. In the present study, we focused on S1 and S2 fibers from the superficial abdominal muscles of the lobster as a model to study the continuum among muscle fiber types. Complementary DNAs (cDNA) encoding an S2 isoform of myosin heavy chain (MHC) and an S2 isoform of tropomyosin (Tm) were isolated from the superficial abdominal flexor muscles of adult lobsters. These identified sequences were used to design PCR primers used in conjunction with RT-PCR and real-time PCR to measure expression levels of these genes in small muscle samples and single fibers. The relative expression of the corresponding S1 MHC and S1 Tm isoforms was measured in the same samples with PCR primers designed according to previously identified sequences. In addition, we measured the relative proportions of MHC, troponin (Tn) T and I protein isoforms present in the same samples to examine the correlation of these proteins with one another and with the MHC and Tm mRNAs. These analyses revealed significant correlations among the different myofibrillar proteins, with the S1 and S2 fibers being characterized by a whole assemblage of myofibrillar isoforms. However, they also showed that small muscle samples, and more importantly single fibers, existed as a continuum from one phenotype to another. Most fibers possessed mixtures of mRNA for MHC isoforms that were unexpected based on protein analysis. These findings illustrate that muscle fibers in general may possess a phenotype that is intermediate between the extremes of 'pure' fiber types, not only at the MHC level but also in terms of whole myofibrillar assemblages. This study supports and extends our recent observations of mixed phenotype fibers in lobster claw and leg muscles. The existence of single fiber polymorphism in an invertebrate species underscores the generality of the phenomenon in skeletal muscles and emphasizes the need for an understanding of the proximal causes and physiological consequences of these intermediate fiber types.

  15. An outbreak of low pathogenic avian influenza in a mixed-species aviculture unit in Dubai in 2005.

    PubMed

    Kent, Jo; Bailey, Tom; Silvanose, Christu-Das; McKeown, Sean; Wernery, Ulrich; Kinne, Joerg; Manvell, Ruth

    2006-09-01

    This case describes an outbreak of low pathogenic hemagglutinin 9 neuraminidase 2 avian influenza virus (AIV) in two white-bellied bustards (Eupodotis senegalensis), one stone curlew (Burhinus oedicnemius), and a blacksmith plover (Antibyx armatus) in a private zoologic collection in Dubai, United Arab Emirates. The four birds showed signs of respiratory disease, and all died as a result of disease or euthanasia. Attention has been paid to the diagnostic process and common differential diagnosis for upper respiratory tract disease in bustards, curlews, and plovers. To the knowledge of the authors, AIV has not been previously described in these species.

  16. New Orleans to Venice, Louisiana Hurricane Protection Project, Draft Supplemental Environmental Impact Statement. Appendixes.

    DTIC Science & Technology

    1984-02-01

    green sea turtle " and Atlantic loggerhead sea...Eskimo Curlew THREATENED SPECIES Green Sea Turtle Atlantic Loggerhead Sea Turtle Due to Similarity of Appearance American Alligator The proposed project...openwater, it is not felt it will influence the alligator population in this area. h. Green Sea Turtle . The Green Sea Turtle (Chelonia mydas)

  17. The American Ornithologists' Union and bird conservation: recommitment to the revolution

    Treesearch

    John W. Fitzpatrick

    2005-01-01

    Exactly one hundred years ago, with North America in full-fledged environmental crisis, prominent members of the American Ornithologists' Union (AOU) participated in major political and social upheaval. A century of unrestrained exploitation had reached catastrophic proportions, with Passenger Pigeons and Eskimo Curlews representing only the tip of an iceberg....

  18. Cloning, distribution and effects of season and nutritional status on the expression of neuropeptide Y (NPY), cocaine and amphetamine regulated transcript (CART) and cholecystokinin (CCK) in winter flounder (Pseudopleuronectes americanus).

    PubMed

    MacDonald, Erin; Volkoff, Hélène

    2009-06-01

    cDNAs encoding for neuropeptide Y (NPY), cocaine and amphetamine regulated transcript (CART) and cholecystokinin (CCK) were cloned in winter flounder, a species that undergoes a period of natural fasting during the winter. Tissue distribution studies show that these peptides are present in several peripheral tissues, including gut and gonads, as well as within the brain. We assessed the effects of season and fasting on the expression of these peptides. Our results show that NPY and CCK, but not CART, show seasonal differences in expression with higher hypothalamic NPY and lower gut CCK expression levels in the winter. In the summer, fasting induced an increase in hypothalamic NPY expression levels and a decrease in gut CCK levels, but did not affect hypothalamic CART expression levels. None of the peptides examined was affected by fasting in the winter. Our results suggest that NPY and CCK, but maybe not CART, might have a major role in the regulation of feeding in winter flounder and might contribute to the seasonal fluctuations in appetite in this species.

  19. Reduction in organic contaminant exposure and resultant hepatic hydropic vacuolation in winter flounder (Pseudopleuronectes americanus) following improved effluent quality and relocation of the Boston sewage outfall into Massachusetts Bay, USA: 1987-2003.

    PubMed

    Moore, Michael; Lefkovitz, Lisa; Hall, Maury; Hillman, Robert; Mitchell, David; Burnett, Jay

    2005-02-01

    Effluent upgrades for metropolitan Boston have included toxicant reduction, primary and secondary treatment and outfall extension. Between 1992 and 2003 winter flounder at five stations were surveyed annually for liver and muscle burden and chronic hepatic sub-lethal impacts of polynuclear and halogenated aromatic hydrocarbons, and metals. Trends in flounder availability and fin condition were also examined. In 1988 12% of the adult winter flounder in Boston Harbor exhibited hepatic neoplasms and up to 80% had hepatic hydropic vacuolation (HV). Tumor prevalence fell to 0-2% and HV to <50% by 1996. Since then tumors have been absent, while a steady prevalence of HV has persisted, consistent with lower hydrocarbon loading and tissue levels. Contaminants and HV also fell with distance from the Boston outfall. After the outfall extension was activated in 2000, there has been no significant change in flounder liver health at the new outfall site.

  20. Gas Hydrate Exploration, Mid Chilean Coast; Geochemical-Geophysical Survey

    DTIC Science & Technology

    2006-12-27

    Scleractinia - - - - - - - - Nemertinea - - Mollusca Bivalvia + - + - - ++ + - + - + - Aplacophora...Caelorinchus fasciatus and three unknow species) were observed. In addition, fauna inside stones was found ( Mollusca : Leptochiton americanus

  1. SMES-ETM Technical Analysis Report.

    DTIC Science & Technology

    2007-11-02

    the American peregrine falcon, aplomado falcon, bald eagle, whooping crane , and interior least tern. The sites are within the feeding range of the...piping plover, black-capped vireo, and possibly the whooping crane . To mitigate the potential effects of the magnetic fields on birds it would be...birds at the Hanford Site and could possibly result in direct effects on the long-billed curlew. The sand hill crane , which is on the threatened

  2. Ribosomal RNA structure in the diploid and phylogenetically polyploid amphibian species Hyla and Odontophrynus.

    PubMed

    Leipoldt, M; Kellner, M

    1984-01-01

    Ribosomal RNA of the diploid amphibian species Hyla chrysoscelis and Odontophrynus americanus is structurally modified by hidden breaks. Phylogenetically polyploid related species like the tetraploid Hyla versicolor, the tetraploid Odontophrynus americanus and the octoploid Ceratophrys ornata do not show hidden breaks in ribosomal RNA. Structural modifications of rRNA molecules in diploid amphibians has no detectable effect on the ribosomal activity in vitro.

  3. 77 FR 74500 - Proposed Habitat Conservation Plan/Natural Community Conservation Plan for Western Butte County...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-14

    ... blackbird (Agelaius tricolor), yellow-breasted chat (Icteria virens), bank swallow (Riparia riparia), Western burrowing owl (Athene ] cunicularia hypugea), western yellow-billed cuckoo (Coccyzus americanus... (Phrynosoma blainvillii), Western pond turtle (Actinemys marmorata), foothill yellow-legged frog (Rana...

  4. Posthurricane Survey of Experimental Dunes on Padre Island, Texas.

    DTIC Science & Technology

    1983-03-01

    Fimbristylis castanea 5 35 2 ______________ Scirpus americanus_____________ _______ ______ _ _______ Leguminosae ... Leguminosae _____________ Baptisa aleucophaea ___________ _________ Cassia fasciculata 4 1 T 4_____9 __ Euphorb iaceae _______ Croton capitatus - -TTI TCroton... Leguminosae ______ Baptisia leucophaea ______ ______ _______ _______ Cassia fasciculata 43_____ Euphorbiaceae______ Croton capitatus_______

  5. An extensive comparison of the effect of anthelmintic classes on diverse nematodes

    USDA-ARS?s Scientific Manuscript database

    Soil-transmitted helminths are parasitic nematodes that inhabit the human intestine. These parasites, which include two hookworm species, Ancylostoma duodenale and Necator americanus, the whipworm Trichuris trichiura, and the large roundworm Ascaris lumbricoides, infect upwards of two billion people...

  6. Simple pulmonary eosinophilia

    MedlinePlus

    ... Pneumocystis jirovecii A parasite, including the roundworms Ascariasis lumbricoides , or Necator americanus , or the hookworm Ancylostoma duodenale ... contents ( gastric lavage ) may show signs of the Ascaris worm or another parasite. Treatment If you are ...

  7. Varestrongylus eleguneniensis sp. n. (Nematoda: Protostrongylidae): a widespread, multi-host lungworm of wild North American ungulates, with an emended diagnosis for the genus and explorations of biogeography

    USDA-ARS?s Scientific Manuscript database

    Varestrongylus eleguneniensis sp. n. is established for a recently discovered protostrongylid nematode found in caribou (Rangifer tarandus), muskoxen (Ovibos moschatus) and moose (Alces americanus), hosts that collectively occupy an extensive geographic range across northern North America. Descripti...

  8. Stable carbon and oxygen isotope ratios of winter flounder otoliths assess connectivity between juvenile and adult habitats

    EPA Science Inventory

    Winter flounder populations (Pseudopleuronectes americanus) have significantly declined in recent years along the Rhode Island, USA coastline. The reasons for this decline are not completely clear; however, habitat loss may be a factor. Therefore, knowledge of connectivity betwee...

  9. Saptial and Temporal in Stable Carbon and Oxygen Isotope Ratios of Juvenile Winter Flounder Otoliths From Selected Nursery Areas

    EPA Science Inventory

    Winter flounder (Pseudopleuronectes americanus) populations have supported large commercial and recreational fisheries along the coast of New England. In recent years, however, the population of this important species has declined precipitously in some areas, especially Narragan...

  10. Saptial and Temporal in Stable Carbon and Oxygen Isotope Ratios of Juvenile Winter Flounder Otoliths From Selected Nursery Areas

    EPA Science Inventory

    Winter flounder (Pseudopleuronectes americanus) populations have supported large commercial and recreational fisheries along the coast of New England. In recent years, however, the population of this important species has declined precipitously in some areas, especially Narragan...

  11. Temporal trends in nitrogen isotope ratios of winter flounder collected from Rhode Island coastal systems

    EPA Science Inventory

    Nitrogen isotope ratios (15N) were measured in muscle tissue of juvenile winter flounder, Pseudopleuronectes americanus, collected from several estuarine systems along the coast of Rhode Island, USA, including Narragansett Bay, Narrow River and three coastal lagoons. Fish collect...

  12. Temporal trends in nitrogen isotope ratios of winter flounder collected from Rhode Island coastal systems

    EPA Science Inventory

    Nitrogen isotope ratios (15N) were measured in muscle tissue of juvenile winter flounder, Pseudopleuronectes americanus, collected from several estuarine systems along the coast of Rhode Island, USA, including Narragansett Bay, Narrow River and three coastal lagoons. Fish collect...

  13. Optimizing a 16S rRNA-based double stranded DNA bindng Q-PCR method for detection of Candidatus Liberibacter species associated with plants and psyllids

    USDA-ARS?s Scientific Manuscript database

    Four Candidatus Liberibacter species (asiaticus, africanus, americanus, and psyllaurous) are phloem-limited bacteria associated with severe plant diseases. Psyllaurous is linked to psyllids yellowing in solanaceous plants while the other three species are associated with citrus greening or Huanglong...

  14. Clues into the metagenome of huanglongbing infected citrus by analysis of ancillary sequences from Ion Torrent whole genome Candidatus Liberibacter asiaticus sequencing

    USDA-ARS?s Scientific Manuscript database

    Huanglongbing (HLB) is a globally devastating disease of citrus. Presently, three etiological agents are associated with HLB and include; Candidatus Liberibacter asiaticus (CLas), Candidatus Liberibacter americanus; and Candidatus Liberibacter africanus. Attempts to determine alternate (non-Liberi...

  15. High Strength and Light-weight Materials Inspired by the Exoskeleton of Arthropods

    DTIC Science & Technology

    2010-01-01

    previous study, where Homarus americanus (American lobster ) and Callinectes sapidus (Atlantic blue crab) were investigated [1]. Image analysis via SEM...Glancey JL and Karlsson AM, Mechanical behavior of bio-inspired laminate composites, in review Page 3 of 6 (A) Blue Crab and Lobster (B...Japanese Beetle Fig. 1 Schematic of the upper structural levels of a (A) Homarus americanus (American lobster ) exoskeleton [1] and (B) Popillia

  16. Recovery of Oswaldotrema nacinovici from Whimbrels (Aves) in Korea.

    PubMed

    Lee, Young-Il; Chung, Ok-Sik; Seo, Min

    2016-12-01

    Adult specimens of Oswaldotrema nacinovici (Digenea: Philophthalmidae) have been first identified in Korea from 2 migratory birds (whimbrels, Numenius phaeopus) which were found dead at a western seashore area near Gunsan. The worms were recovered in the intestine of these birds. The worms were morphologically characterized by a large ventral sucker in comparison to the oral sucker, an external seminal vesicle extending beyond the posterior margin of the ventral sucker, and conspicuous uterine seminal receptacle. It was noteworthy that metacercariae-like bodies were contained within the inflated regions of 2 ceca. Other intestinal trematode species found in whimbrels included Spelotrema pygmeum, Gynaecotyla squatarolae, Maritrema obstipum, and Himasthla megacotyle. Zoonotic potential of these trematode species should be taken into considerations.

  17. Recovery of Oswaldotrema nacinovici from Whimbrels (Aves) in Korea

    PubMed Central

    Lee, Young-Il; Chung, Ok-Sik; Seo, Min

    2016-01-01

    Adult specimens of Oswaldotrema nacinovici (Digenea: Philophthalmidae) have been first identified in Korea from 2 migratory birds (whimbrels, Numenius phaeopus) which were found dead at a western seashore area near Gunsan. The worms were recovered in the intestine of these birds. The worms were morphologically characterized by a large ventral sucker in comparison to the oral sucker, an external seminal vesicle extending beyond the posterior margin of the ventral sucker, and conspicuous uterine seminal receptacle. It was noteworthy that metacercariae-like bodies were contained within the inflated regions of 2 ceca. Other intestinal trematode species found in whimbrels included Spelotrema pygmeum, Gynaecotyla squatarolae, Maritrema obstipum, and Himasthla megacotyle. Zoonotic potential of these trematode species should be taken into considerations. PMID:28095668

  18. Intragenus (Campylomormyrus) and intergenus hybrids in mormyrid fish: Physiological and histological investigations of the electric organ ontogeny.

    PubMed

    Kirschbaum, Frank; Nguyen, Linh; Baumgartner, Stephanie; Chi, Hiu Wan Linda; Wolfart, Rene; Elarbani, Khouloud; Eppenstein, Hari; Korniienko, Yevheniia; Guido-Böhm, Lilian; Mamonekene, Victor; Vater, Marianne; Tiedemann, Ralph

    2017-01-17

    African weakly electric mormyrid fish show a high diversity of their electric organ discharge (EOD) both across and within genera. Thanks to a recently developed technique of artificial reproduction in mormyrid fish, we were able to perform hybridizations between different genera and within one genus (Campylomormyrus). The hybrids of intergenus hybridizations exhibited different degrees of reduced survival related to the phylogenetic distance of the parent species: hybrids of the crosses between C. rhynchophorus and its sister genus Gnathonemus survived and developed normally. Hybrids between C. rhynchophorus and a Mormyrus species (a more basal clade compared to Campylomormyrus s) survived up to 42days and developed many malformations, e.g., at the level of the unpaired fins. Hybrids between C. numenius and Hippopotamyrus pictus (a derived clade, only distantly related to Campylomormyrus) only survived for two days during embryological development. Eight different hybrid combinations among five Campylomormyrus species (C. tamandua, C. compressirostris, C. tshokwe, C. rhynchophorus, C. numenius) were performed. The aim of the hybridizations was to combine species with (1) either caudal or rostral position of the main stalk innervating the electrocytes in the electric organ and (2) short, median or long duration of their EOD. The hybrids, though they are still juveniles, show very interesting features concerning electrocyte geometry as well as EOD form and duration: the caudal position of the stalk is prevailing over the rostral position, and the penetration of the stalk is dominant over the non-penetrating feature (in the Campylomormyrus hybrids); in the hybrid between C. rhynchophorus and Gnathonemus petersii it is the opposite. When crossing species with long and short EODs, it is always the long duration EOD that is expressed in the hybrids. The F1-Hybrids of the cross C. tamandua×C. compressirostris are fertile: viable F2-fish could be obtained with artificial

  19. Epidemiology of human hookworm and Ascaris lumbricoides infestations in rural Gambia.

    PubMed

    Palmer, D R; Bundy, D A

    1995-08-01

    In a cross-sectional study of helminth infections in a rural village in The Gambia, West Africa, hookworm, probably Necator americanus and Ascaris lumbricoides were found to be the most prevalent helminths present at prevalence levels of 30% and 25% respectively. Other parasites present were Trichuris trichiura (2.4%) and Schistosoma mansoni (1.5%). The mean egg counts of N. americanus and A. lumbricoides in all age groups and in the total population were low. Egg counts between age and sex groups were not statistically significant. The frequency distributions of both N. americanus and A. lumbricoides were overdispersed with the majority of the sample population producing none or few eggs, and a small minority producing relatively large amounts of eggs. Large variance: mean ratios within age groups and the total study population suggested a high degree of aggregation of the parasites in this community.

  20. New explorations along the northern shores of Lake Bonneville

    USGS Publications Warehouse

    Oviatt, Charles G.; Miller, D.M.

    1997-01-01

    This field trip begins in Salt Lake City and makes a clockwise circuit of Great Salt Lake, with primary objectives to observe stratigraphie and geomorphic records of Lake Bonneville. Stops include Stansbury Island, Puddle Valley, gravel pits at Lakeside and the south end of the Hogup Mountains, several stops in Curlew Valley and Hansel Valley, and a final stop at the north end of Great Salt Lake east of the Promontory Mountains. Stratigraphie observations at gravel-pit and natural exposures will be linked to interpretations of lake-level change, which were caused by climate change. Evidence of paleoseismic and volcanic activity will be discussed at several sites, and will be tied to the lacustrine stratigraphic record. The trip provides an overview of the history of Lake Bonneville and introduces participants to some new localities with excellent examples of Lake Bonneville landforms and stratigraphy.

  1. Threatened and endangered wildlife survey: Vacherie Dome area, Louisiana

    SciTech Connect

    Not Available

    1985-01-01

    Review of the available literature concerning the previous distribution of animals now considered to be threatened or endangered suggests that the following species may once have occupied the project area in Webster and Bienville Parishes, Louisiana: Florida panther, bald eagle, Arctic peregrine falcon, red-cockaded woodpecker, ivory-billed woodpecker, red wolf, and Eskimo curlew. The Louisiana pine snake is not officially listed at this time although it is considered to be a candidate for inclusion on the federal list pending further research on its population and distribution. Based on previous experience within northwestern Louisiana and other recent evidence, it is concluded that the red-cockaded woodpecker (Picoides borealis) is the only animal listed or proposed as threatened or endangered which may actually now be found there.

  2. Hematologic and plasma biochemical reference values in Indian peafowl (Pavo cristatus).

    PubMed

    Samour, Jaime; Naldo, Jesus; Rahman, Habeeb; Sakkir, Mohammed

    2010-06-01

    Blood samples were collected from captive, adult, clinically normal Indian peafowl (Pavo cristatus) for hematologic and plasma biochemical analyses. Hematologic parameters investigated were total red blood cell count, hemoglobin, packed cell volume, fibrinogen, mean cell volume, mean cell hemoglobin, mean cell hemoglobin concentration, total white blood cell count, differential white blood cell count, and thrombocyte count. Plasma biochemical parameters investigated were alanine aminotransferase, alkaline phosphatase, amylase, aspartate aminotransferase, bile acids, total bilirubin, blood urea nitrogen, calcium, cholesterol, creatinine, creatine kinase, gamma glutamyltransferase, lactate dehydrogenase, glucose, iron, phosphorus, and uric acid, as well as plasma protein electrophoresis. Results were compared with values from studies done in houbara bustards (Chlamydotis undulata), kori bustards (Ardeotis kori), stone curlews (Burhinus oedicnemus), and taxonomically related species, including ring-necked pheasants (Phasianus colchicus), red-legged partridges (Alectoris rufa), Kashmir native fowl (Kashmirfavorella), and Bangladesh native, Fayoumi, and Assil fowl (Gallus domesticus).

  3. [Advantages and limitations of interspecies associations in northern migratory sandpipers (Charadrii, Aves)].

    PubMed

    Gavrilov, V V

    2014-01-01

    Investigations were carried out at two stations of Ornithological Unit, IBPN FEB RAS, located in Nizhnekolymsk District, Yakutia, starting from May 15-20 in 1984, 1985, 1987, 1988, and 1990; at the northern coast of Pukhovoy Bay, Southern Island of Novaya Zemlya starting from June 1 in 1994; at Cape Beliy Nos, the Yugorsky Peninsula, starting from June 1 in 1995-1997. Classic associations are detected in interspecies flocks of sandpipers between the following species: the Pacific golden plover and the curlew sandpiper, the pectoral sandpiper and the long-billed dowitcher, the pectoral sandpiper and the dunlin, the grey plover and the dunlin. However, total amount of birds that form associations is not large. In species of group "A" (the grey plover, the Pacific golden plover, the pectoral sandpiper), no difference has been observed in migratory birds behavior within inter- or conspecific flocks. Species of group "B" (the dunlin, the curlew sandpiper, the long-billed dowitcher), on the contrary, change their behavior sharply depending on whether they belong to an association or not. Species of group "A" do not get any advantages when forming an association. Unlike them, species of group "B" profit from associating: a part of time spent in foraging substantially increases; more time is spent on rest and less time is spent on reconnaissance and vigilance (readiness for actions); safety of birds is enhanced. On the other hand, in species of group "B" there are also disadvantages related with associating: i.e., interspecies competition for food; foraging in suboptimal habitats which, in turn, may lead to notable increase of time spent by birds in foraging. An assumption is put forward that in species of group "B" advantages and limitations of associating cancel each other to a certain extent, and this explains rather small number of birds forming associations.

  4. Intense predation cannot always be detected experimentally: A case study of shorebird predation on nereid polychaetes in South Africa

    NASA Astrophysics Data System (ADS)

    Kalejta, B.

    The effect of predation by curlew sandpipers Calidris ferruginea L. and grey plovers Pluvialis squatarola (L.) on populations of nereid worms Ceratonereis keiskama (Day) and C. erythraeensis (Fauvel) was studied at the Berg River estuary, South Africa, by comparing observations of shorebird-foraging intensity with the results of a population study of two species of nereid worms within and outside bird exclosures. The study was carried out during the four-month period prior to northward migration of shorebirds. Population structure of the two nereid species differed considerably. Ceratonereis keiskama reproduced earlier than C. erythraeensis and only young individuals were present during the study. By contrast, old C. erythraeensis were available to the birds at the start of the experiment and young animals entered the population during the experiment. Despite selective predation on certain size classes of nereids by the birds, no significant changes in the population structure of either nereid were detected by the cage experiment. Numbers and biomass of both Ceratonereis spp. in paired controls and cages tracked each other and did not diverge as predicted. A consistent difference in the depth stratification of the two nereids may, however, have been due to predation pressure. Curlew sandpipers were calculated to remove 3112 nereids per m 2 during the three months, equivalent to 4.4. g (dry weight) per m 2. This represents 58% of the initial numbers and 77% of the initial biomass of nereids. Although predation on nereids by waders was exceptionally high at the Berg River estuary, any depletion in numbers or biomass of nereids caused by these predators was masked by the reproduction of the nereids. The fact that the predators' high energy requirements prior to northward migration coincide with the period of peak production of invertebrate prey makes the Berg River estuary an exceptionally favourable wintering area.

  5. Wind effects on prey availability: How northward migrating waders use brackish and hypersaline lagoons in the sivash, Ukraine

    NASA Astrophysics Data System (ADS)

    Verkuil, Yvonne; Koolhaas, Anita; Van Der Winden, Jan

    Large numbers of waders migrating northward in spring use the Sivash, a large system of shallow, brackish and hypersaline lagoons in the Black Sea and Azov Sea region (Ukraine). The bottoms of these lagoons are often uncovered by the wind. Hence, for waders the time and space available for feeding depend on wind conditions. In hypersaline lagoons the benthic and pelagic fauna was very poor, consisting mainly of chironomid larvae (0.19 g AFDM·m -2) and brine shrimps Artemia salina, respectively. Brine shrimp abundance was correlated with salinity, wind force, wind direction and water depth. Dunlin Calidris alpina and curlew sandpiper Calidris ferruginea were the only species feeding on brine shrimp. As brine shrimp densities are higher in deeper water, smaller waders such as broad-billed sandpipers Limicola falcinellus are too short-legged to reach exploitable densities of brine shrimp. In brackish lagoons the benthic and pelagic fauna was rich, consisting of polychaetes, bivalves, gastropods, chironomid larvae, isopods and amphipods (8.9 to 30.5 g AFDM·m -2), but there were no brine shrimps. Prey biomass increased with the distance from the coast, being highest on the site that was most frequently inundated. Dunlin, broad-billed sandpiper and grey plover Pluvialis squatarola were the most abundant birds in the brackish lagoon. Due to the effects of wind-tides only a small area was usually available as a feeding site. Gammarus insensibilis was the alternative prey resource in the water layer, and their density varied with wind direction in the same way as brine shrimp. Curlew sandpipers and dunlins in the hypersaline lagoons and broad-billed sandpipers in the brackish lagoons often changed feeding sites, probably following the variation in prey availability. Only because of the large size and variety of lagoons are waders in the Sivash always able to find good feeding sites.

  6. Effect of fuels reduction on American martens and their prey.

    Treesearch

    Evelyn L. Bull; Arlene K. Blumton

    1999-01-01

    The effect of a fuels reduction treatment on small mammals was investigated in lodgepole pine (Pinus contorta) and mixed conifer stands by trapping and track surveys in northeastern Oregon. The number of red squirrel (Tamiasciurus hudsonicus) and snowshoe hare (Lepus americanus) tracks decreased in all...

  7. Predicting carnivore occurrence with noninvasive surveys and occupancy modeling

    Treesearch

    Robert Long; Therese Donovan; Paula MacKay; William Zielinski; Jeffrey. Buzas

    2011-01-01

    Terrestrial carnivores typically have large home ranges and exist at low population densities, thus presenting challenges to wildlife researchers. We employed multiple, noninvasive survey methods—scat detection dogs, remote cameras, and hair snares—to collect detection–nondetection data for elusive American black bears (Ursus americanus), fishers...

  8. Combined use of mark-recapture and genetic analyses reveals response of a black bear population to changes in food productivity

    Treesearch

    Barbara S. McCall; Michael S. Mitchell; Michael K. Schwartz; Jim Hayden; Samuel A. Cushman; Pete Zager; Wayne F. Kasworm

    2013-01-01

    We used mark-recapture analysis to investigate the dynamics of a black bear (Ursus americanus) population in northern Idaho where food availability varies seasonally and annually. We conducted noninvasive genetic sampling (NGS) during 2003-2006 in the Purcell Mountains of Idaho to collect black bear DNA samples for individual identification of bears. We used a...

  9. DNA markers for identifying individual snowshoe hares using field-collected pellets

    Treesearch

    Michael K. Schwartz; Kristine L. Pilgrim; Kevin S. McKelvey; Pilar T. Rivera; Leonard F. Ruggiero

    2007-01-01

    Snowshoe hare (Lepus americanus) abundance has been of interest to wildlife biologists, as hares are essential prey items for many rare and endangered predators. Snowshoe hare abundance has most commonly been estimated through indices such as pellet counts. While pellet counts may be useful in the areas they are developed and when hares are dense,...

  10. Feeding patterns of migratory and non-migratory fourth instar larvae of two coexisting Chaoborus species in an acidic and metal contaminated lake: Importance of prey ingestion rate in predicting metal bioaccumulation

    USGS Publications Warehouse

    Croteau, M.-N.; Hare, L.; Marcoux, P.

    2003-01-01

    We studied diel variations in the feeding habits and migratory behaviors of two coexisting Chaoborus species in an acidic and metal contaminated lake (Lake Turcotte, QC, Canada). We found that although the zooplankton community was dominated by rotifers, both Chaoborus species fed mostly on chironomids and crustaceans despite the relatively low abundance of these prey types in the lake plankton. Chaoborus americanus larvae fed on those of Chaoborus punctipennis, but not vice versa. The non-migratory species (C. americanus) fed throughout the day and night whereas the migratory species (C. punctipennis) fed only at night while in the water column. The larger-bodied C. americanus consumed more prey and had a more diverse diet than did the smaller-bodied C. punctipennis. Differences in feeding habits between the Chaoborus species inhabiting Lake Turcotte (prey biomass, prey types) likely explain in part their ability to coexist. Attempts to predict Cd in the Chaoborus species using our measurements of Cd in their prey and their prey ingestion rates met with mixed success; although we correctly predicted higher Cd concentrations for C. americanus larvae than for C. punctipennis larvae, we under-predicted absolute Cd concentrations. We suggest that studies such as ours that are based on analyses of gut contents of larvae collected at intervals of 4h or longer likely underestimate prey ingestion rates.

  11. An improved method of DNA extraction from Diaphorina citri for HLB detection

    USDA-ARS?s Scientific Manuscript database

    Huanglongbing (HLB) is a devastating disease of citrus that is transmitted by two citrus psyllids. Diaphorina citri transmits Candidatus Liberibacter asiaticus (Las) and Ca. L. americanus (Lam), and Trioza erytreae transmits Ca. L. africanus (Laf). Ca. Liberibacter species can be detected in DNA ex...

  12. Contagious ecthyma in mountain goat of coastal British Columbia.

    PubMed

    Hebert, D M; Samuel, W M; Smith, G W

    1977-04-01

    Contagious ecthyma has been reported previously from mountain goat (Oreamnos americanus) in one restricted area of eastern British Columbia. A second focus of infection is reported for mountain goat from western British Columbia. Diagnosis was based on appearance of lesions at necropsy, histopathology and demonstration of poxvirus with the electron microscope. The epizootiology of this infection in mountain goat is discussed briefly.

  13. Detecting genotyping errors and describing black bear movement in northern Idaho

    Treesearch

    Michael K. Schwartz; Samuel A. Cushman; Kevin S. McKelvey; Jim Hayden; Cory Engkjer

    2006-01-01

    Non-invasive genetic sampling has become a favored tool to enumerate wildlife. Genetic errors, caused by poor quality samples, can lead to substantial biases in numerical estimates of individuals. We demonstrate how the computer program DROPOUT can detect amplification errors (false alleles and allelic dropout) in a black bear (Ursus americanus) dataset collected in...

  14. 77 FR 2993 - Final Environmental Impact Statement and Record of Decision on Oncor Electric Delivery Company's...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-20

    ... houstonensis) Whooping crane (Grus americana) Golden-cheeked warbler (Dendroica chrysoparia) Black-capped vireo... paradoxus) Louisiana black bear (Ursus americanus luteolus) Take of listed plant species is not defined in... Agency had ``no objections'' to implementation of the preferred alternative, and the Federal Aviation...

  15. Growth of bear-damaged trees in a mixed plantation of Douglas-fir and red alder.

    Treesearch

    Richard E. Miller; Harry W. Anderson; Donald L. Reukema; Timothy A. Max

    2007-01-01

    Incidence and effects of tree damage by black bear (Ursus americanus altifrontalis) in a 50-year-old, coast Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii) plantation are described. Bears girdled or partially girdled 35 dominant or codominant Douglas-fir trees per acre, but only in that...

  16. Non-territorial floaters in Great Horned Owls (Bubo virginianus)

    Treesearch

    Christoph Rohner

    1997-01-01

    The ecology and behavior of non-territorial owls are basically unknown. I studied the integration of young Great Horned Owls (Bubo virginianus) into the territorial breeding population from 1988-1993 in the southwestern Yukon, Canada, during a peak and decline of the population cycle of snowshoe hares (Lepus americanus). Fifty-five...

  17. Nitrogen Isotope Ratios of Juvenile Winter Flounder as an Indicator of Anthropogenic Nitrogen Inputs to Estuarine Systems

    EPA Science Inventory

    Nitrogen isotope ratios (15N) were measured in muscle tissue of juvenile winter flounder, Pseudopleuronectes americanus, collected from several estuarine systems (lagoons, river, bay) along the coast of Rhode Island, USA over a three-year period. Significant differences i...

  18. IMPACT OF ELEVATED TEMPERATURE ON THE GROWTH, SURVIVAL, AND TROPHIC DYNAMICS OF WINTER FLOUNDER LARVAE: A MESOCOSM STUDY

    EPA Science Inventory

    Winter flounder (Pseudopleuronectes americanus) is a dominant commercial fish in Narragansett Bay, Rhode Island, and yet factors controlling its recruitment remain unclear. An experiment was conducted with six 13-m3 land-based mesocosms (5 m deep) from February to April 1997 to a...

  19. Geographic variation in the yellow-billed cuckoo

    USGS Publications Warehouse

    Banks, R.C.

    1988-01-01

    Populations of the Yellow-billed Cuckoo, Coocyzus americanus, west of the Rocky Mountains have average wing lengths slightly greater than those of eastern North America, but the difference is not sufficient for taxonomic recognition. There is no geographically oriented variation in bill size or color, and the species is best considered monotypic.

  20. Aquatic plant control research program. Interactive influences of light and temperature on the growth and morphology of submersed fresh water macrophytes. Final report

    SciTech Connect

    Barko, J.W.; Hardin, D.G.; Matthews, M.S.

    1984-02-01

    Variations in the growth and morphology of three North American fresh-water macrophyte species, Elodea canadensis Michx., Potamogeton nodosus Poiret (P. americanus), and Vallisneria americana Michx., were investigated over broad experimental ranges of light and temperature. Response variables considered in the study included biomass production, shoot density, shoot length, and various characteristics of leaf form.

  1. Archaeological Testing and Survey: Testing of Three Sites and Survey of a Road Detour within Proposed Project Construction Zones, Burlington Dam Flood Control Project Area, Upper Souris River, North Dakota,

    DTIC Science & Technology

    1980-01-01

    suitable habitat for a variety of animals. 7 ................................... Animal influents include a number of smaller mammals . The ground...1926:33, 41, 194). Other mammals may have included bighorn sheep (Ovis canadensis), moose (Alces americanus) and caribou (Rangiver caribou) (Bailey 1926...Upland Prairie ecozone which overlooks the river valley. Small mammals such as rabbit, badger, and fox generally inhabit this gently sloping or flat

  2. Overcoming Misinterpretation and Irrationality: Doing Ethics at the Intersection of Social Justice, Liberation, and Civil/Human Rights

    ERIC Educational Resources Information Center

    Ross, Rosetta E.

    2012-01-01

    Historian of religions Charles Long uses the term "American cultural language" to identify discursive challenges to democracy and social justice in the Unites States. The American cultural language, Long says, is the "misinterpretation" of humanness and freedom conveyed when the term "American"--used to signify…

  3. Fire drives transcontinental variation in tree birch defense against browsing by snowshoe hares

    Treesearch

    John P. Bryant; Thomas P. Clausen; Robert K. Swihart; Simon M. Landhäusser; Michael T. Stevens; Christopher D. B. Hawkins; Suzanne Carrière; Andrei P. Kirilenko; Alasdair M. Veitch; Richard A. Popko; David T. Cleland; Joseph H. Williams; Walter J. Jakubas; Michael R. Carlson; Karin Lehmkuhl Bodony; Merben Cebrian; Thomas F. Paragi; Peter M. Picone; Jeffery E. Moore; Edmond C. Packee; Thomas Malone

    2009-01-01

    Fire has been the dominant disturbance in boreal America since the Pleistocene, resulting in a spatial mosaic in which the most fire occurs in the continental northwest. Spatial variation in snowshoe hare (Lepus americanus) density reflects the fire mosaic. Because fire initiates secondary forest succession, a fire mosaic creates...

  4. IMPACT OF ELEVATED TEMPERATURE ON THE GROWTH, SURVIVAL, AND TROPHIC DYNAMICS OF WINTER FLOUNDER LARVAE: A MESOCOSM STUDY

    EPA Science Inventory

    Winter flounder (Pseudopleuronectes americanus) is a dominant commercial fish in Narragansett Bay, Rhode Island, and yet factors controlling its recruitment remain unclear. An experiment was conducted with six 13-m3 land-based mesocosms (5 m deep) from February to April 1997 to a...

  5. Herpetofaunal species composition and relative abundance among three New England forest types

    Treesearch

    Richard M. DeGraaf; Deborah D. Rudis

    1990-01-01

    Drift fences and pitfall traps captured > 2000 reptiles and amphibians during 2 years; the most common species were wood frog (Rana sylvatica), American toad (Bufo americanus), and redback salamander (Plethodon cinereus). There were differences in species abundances among streamside and upland...

  6. Trends in nitrogen isotope ratios of juvenile winter flounder reflect changing nitrogen inputs to Rhode Island, USA estuarine systems

    EPA Science Inventory

    Nitrogen isotope ratios (d 15N) in juvenile winter flounder, Pseudopleuronectes americanus, were used to examine changes in nitrogen inputs to several Rhode Island, USA estuarine systems. Fish were collected over two three-year periods with a ten-year interval between sampling pe...

  7. ASSESSING HABITAT QUALITY OF MOUNT HOPE BAY AND NARRAGANSETT BAY USING GROWTH, RNA:DNA, AND FEDDING HABITS OF CAGED JUVENILE WINTER FLOUNDER

    EPA Science Inventory

    Somatic growth rates, RNA:DNA, and feeding habits of juvenile Pseudopleuronectes americanus (Winter Flounder) were used to asses small-scale spatio-temporal variations in the habitat quality of Mount Hope Bay and Narragan-sett Bay, RI. Three successive caging experiments (14–16 d...

  8. Archaeal rhizosphere communities differ between the native and invasive lines of the wetland plant phragmites australis (common reed) in a Chesapeake Bay subestuary

    USDA-ARS?s Scientific Manuscript database

    Phragmites australis, a common wetland plant species worldwide, is best known in North America as persistent invasive species. Only in recent decades was a native line, Phragmites australis subsp. americanus, confirmed in North American wetlands. This study investigated whether the two lines suppo...

  9. RELATIONSHIPS BETWEEN HABITAT QUALITY AND DENSITY OF JUVENILE WINTER FLOUNDER

    EPA Science Inventory

    We used a digital video camera mounted to a 1-m beam trawl together with an attached continuous recording YSI sonde and GPS unit to quantify juvenile winter flounder (Pseudopleuronectes americanus) densities and fish habitat. The YSI sonde measured temperature, salinity, dissolve...

  10. USE OF VIDEO TO ACCESS JUVENILE WINTER FLOUNDER DENSITIES AND HABITATS

    EPA Science Inventory

    We used a digital video camera mounted to a 1-m beam trawl together with an attached continuous recording YSI sonde and a GPS unit to quantify juvenile winter flounder (Pseudopleuronectes americanus) densities and fish habitat in Narragansett Bay, RI. The YSI sonde measured te...

  11. 21 CFR 520.905b - Fenbendazole granules.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) Dogs—(i) Amount. 50 mg/kg daily for 3 consecutive days. (ii) Indications for use. For the treatment and... appropriate amount of drug with a small amount of the usual food; dry dog food may require slight moistening... hydatigena, T. krabbei, T. taeniaeformis). (D) Black Bear (Ursus americanus): Ascarid...

  12. 21 CFR 520.905b - Fenbendazole granules.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) Dogs—(i) Amount. 50 mg/kg daily for 3 consecutive days. (ii) Indications for use. For the treatment and... appropriate amount of drug with a small amount of the usual food; dry dog food may require slight moistening... hydatigena, T. krabbei, T. taeniaeformis). (D) Black Bear (Ursus americanus): Ascarid...

  13. 21 CFR 520.905b - Fenbendazole granules.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) Dogs—(i) Amount. 50 mg/kg daily for 3 consecutive days. (ii) Indications for use. For the treatment and... appropriate amount of drug with a small amount of the usual food; dry dog food may require slight moistening... hydatigena, T. krabbei, T. taeniaeformis). (D) Black Bear (Ursus americanus): Ascarid...

  14. 21 CFR 520.905b - Fenbendazole granules.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) Dogs—(i) Amount. 50 mg/kg daily for 3 consecutive days. (ii) Indications for use. For the treatment and... appropriate amount of drug with a small amount of the usual food; dry dog food may require slight moistening... hydatigena, T. krabbei, T. taeniaeformis). (D) Black Bear (Ursus americanus): Ascarid...

  15. 21 CFR 520.905b - Fenbendazole granules.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) Dogs—(i) Amount. 50 mg/kg daily for 3 consecutive days. (ii) Indications for use. For the treatment and... appropriate amount of drug with a small amount of the usual food; dry dog food may require slight moistening... hydatigena, T. krabbei, T. taeniaeformis). (D) Black Bear (Ursus americanus): Ascarid...

  16. Diversity of Frankia Strains in Root Nodules of Plants from the Families Elaeagnaceae and Rhamnaceae

    PubMed Central

    Clawson, Michael L.; Carú, Margarita; Benson, David R.

    1998-01-01

    Partial 16S ribosomal DNAs (rDNAs) were PCR amplified and sequenced from Frankia strains living in root nodules of plants belonging to the families Elaeagnaceae and Rhamnaceae, including Colletia hystrix, Elaeagnus angustifolia, an unidentified Elaeagnus sp., Talguenea quinquenervia, and Trevoa trinervis. Nearly full-length 16S rDNAs were sequenced from strains of Frankia living in nodules of Ceanothus americanus, C. hystrix, Coriaria arborea, and Trevoa trinervis. Partial sequences also were obtained from Frankia strains isolated and cultured from the nodules of C. hystrix, Discaria serratifolia, D. trinervis, Retanilla ephedra, T. quinquenervia, and T. trinervis (Rhamnaceae). Comparison of these sequences and other published sequences of Frankia 16S rDNA reveals that the microsymbionts and isolated strains from the two plant families form a distinct phylogenetic clade, except for those from C. americanus. All sequences in the clade have a common 2-base deletion compared with other Frankia strains. Sequences from C. americanus nodules lack the deletion and cluster with Frankia strains infecting plants of the family Rosaceae. Published plant phylogenies (based on chloroplast rbcL sequences) group the members of the families Elaeagnaceae and Rhamnaceae together in the same clade. Thus, with the exception of C. americanus, actinorhizal plants of these families and their Frankia microsymbionts share a common symbiotic origin. PMID:9726914

  17. Carbon and nitrogen isotope ratios of juvenile winter flounder as indicators of inputs to estuarine systems

    EPA Science Inventory

    Stable carbon and nitrogen isotope ratios were measured in the muscle tissues of young-of-the-year (YOY) winter flounder, Pseudopleuronectes americanus, collected from several estuarine systems along the coast of Rhode Island, USA. These systems included three coastal lagoons (Ni...

  18. The use of radio telemetry in Martes research: techniques and technologies

    Treesearch

    Craig M. Thompson; Rebecca A. Green; Joel Sauder; Kathryn L. Purcell; Richard Sweitzer; Jon. Armeno

    2012-01-01

    Radiotelemetry was fi rst used on a Martes species in 1972, when 5 American martens ( Martes americana ) captured incidentally during a snowshoe hare ( Lepus americanus ) research project in Minnesota were radio-collared. Since then, at least 128 research projects have used radiotelemetry to investigate...

  19. Activity patterns of American martens, fishers, snowshoe hares, and red squirrels in westcentral Montana

    Treesearch

    Kerry R. Foresman; Dean Pearson

    1999-01-01

    We investigated winter activity patterns of American Martens, Martes americana, Snowshoe Hares, Lepus americanus, and Red Squirrels, Tamiasciurus hudsonicus, in westcentral Montana between November 1994 and March 1995 using dual-sensor remote cameras. One hundred percent of Snowshoe Hare (n = 25) observations occurred at night while Martens (n = 85) exhibited...

  20. 75 FR 42375 - Trade Adjustment Assistance for Farmers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-21

    ... Maine Lobstermen's Association on behalf of American lobster (Homarus ] americanus) fishermen who catch and market their lobster in Maine. The Administrator will determine within 40 days whether or not increasing imports of American lobster contributed importantly to a greater than 15-percent decrease in...

  1. 75 FR 45092 - Trade Adjustment Assistance for Farmers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-02

    ... Hampshire Commercial Fishermen's Association on behalf of American lobster (Homarus americanus) fishermen who catch and market their lobster in New Hampshire. The Administrator will determine within 40 days whether or not increasing imports of American lobster contributed importantly to a greater than...

  2. 75 FR 49458 - Trade Adjustment Assistance for Farmers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-13

    ... the University of Rhode Island on behalf of American lobster (Homarus americanus) fishermen who catch and market their lobster in Rhode Island. The Administrator will determine within 40 days whether or not increasing imports of American lobster contributed importantly to a greater than...

  3. 75 FR 23226 - Trade Adjustment Assistance for Farmers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-03

    ... Association on behalf of U.S. fishermen who catch and market live lobsters (Homarus americanus). The Administrator will determine within 40 days whether or not increasing imports of live lobsters (Homarus... lobsters compared to the average of the 3 preceding marketing years. If a determination is affirmative,...

  4. 75 FR 45092 - Trade Adjustment Assistance for Farmers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-02

    ... Massachusetts Lobstermen's Association on behalf of American lobster (Homarus americanus) fishermen who catch and market their lobster in Massachusetts. The FAS Administrator will determine within 40 days whether or not increasing imports of American lobster contributed importantly to a greater than...

  5. Influence of forest structure on the abundance of snowshoe hares in western Wyoming

    Treesearch

    Nathan D. Berg; Eric M. Gese; John R. Squires; Lise M. Aubry

    2012-01-01

    Snowshoe hares (Lepus americanus) are a primary prey species for Canada lynx (Lynx canadensis) in western North America. Lynx management plans require knowledge of potential prey distribution and abundance in the western United States. Whether even-aged regenerating forests or multi-storied forests contain more snowshoe hares is currently unknown. During 2006-...

  6. Synchrony in the snowshoe hare cycle in Northwestern North America, 1970-2012

    Treesearch

    C.J. Krebs; K. Kielland; J.P Bryant; M. O' Donoghue; F. Doyle; C. McIntyre; D. DiFolco; N. Berg; S. Carriere; R. Boonstra; S. Boutin; A. J. Kenney; D. G. Reid; K. Bodony; J. Putera; H. K. Timm; T. Burke.

    2013-01-01

    Snowshoe hares (Lepus americanus Erxleben, 1777) fluctuate in 9–10 year cycles throughout much of their North American range. Regional synchrony has been assumed to be the rule for these cycles, so that hare populations in virtually all of northwestern North America have been assumed to be in phase. We gathered qualitative and quantitative data on...

  7. Black bear population and connectivity in the Sky Islands of Mexico and the United States

    Treesearch

    N. E. Lara-Diaz; C. A. Lopez-Gonzalez; H. Coronel-Arellano; A. Gonzalez-Bernal

    2013-01-01

    The Sky Island region is a mountainous region surrounded by grasslands, deserts and intermountain valleys, located between Mexico and the United States. However, different land management and human impact can have an effect on its wildlife populations. Currently, the border wall poses an immediate threat to the survival of black bears (Ursus americanus), considered an...

  8. Nitrogen Isotope Ratios of Juvenile Winter Flounder as an Indicator of Anthropogenic Nitrogen Inputs to Estuarine Systems

    EPA Science Inventory

    Nitrogen isotope ratios (15N) were measured in muscle tissue of juvenile winter flounder, Pseudopleuronectes americanus, collected from several estuarine systems (lagoons, river, bay) along the coast of Rhode Island, USA over a three-year period. Significant differences i...

  9. USING WINTER FLOUNDER GROWTH RATES TO ASSESS HABITAT QUALITY ACROSS AN ANTHROPOGENIC GRADIENT IN NARRAGANSETT BAY, RI

    EPA Science Inventory

    We used growth rates of juvenile winter flounder Pseudopleuronectes americanus to assess anthropogenic influence on habitat quality at three sites in Narragansett Bay, Rhode Island. The upper bay site, Gaspee Point, had the highest population density and concentration of total ni...

  10. Inhibition of snowshoe hare succinate dehydrogenase activity as a mechanism of deterrence for papyriferic acid in birch

    Treesearch

    Jennifer Sorensen Forbey; Xinzhu Pu; Dong Xu; Knut Kielland; John. Bryant

    2011-01-01

    The plant secondary metabolite papyriferic acid (PA) deters browsing by snowshoe hares (Lepus americanus) on the juvenile developmental stage of the Alaska paper birch (Betula neoalaskana). However, the physiological mechanism that reduces browsing remains unknown. We used pharmacological assays and molecular modeling to test the...

  11. Black-flies and Leucocytozoon spp. as causes of mortality in juvenile Great Horned Owls in the Yukon, Canada

    Treesearch

    D. Bruce Hunter; Christoph Rohner; Doug C. Currie

    1997-01-01

    Black fly feeding and infection with the blood parasite Leucocytozoon spp. caused mortality in juvenile Great Horned Owls (Bubo virginianus) in the Yukon, Canada during 1989-1990. The mortality occurred during a year of food shortage corresponding with the crash in snowshoe hare (Lepus americanus) populations. We...

  12. Satellite monitoring of black bear.

    NASA Technical Reports Server (NTRS)

    Craighead, J. J.; Craighead, F. C., Jr.; Varney, J. R.; Cote, C. E.

    1971-01-01

    Description of a feasibility experiment recently performed to test the use of a satellite system for telemetering environmental and physiological data from the winter den of a 'hibernating' black bear, Ursus americanus. The instrumentation procedure and evaluations of the equipment performance and sensory data obtained are discussed in detail.

  13. Overcoming Misinterpretation and Irrationality: Doing Ethics at the Intersection of Social Justice, Liberation, and Civil/Human Rights

    ERIC Educational Resources Information Center

    Ross, Rosetta E.

    2012-01-01

    Historian of religions Charles Long uses the term "American cultural language" to identify discursive challenges to democracy and social justice in the Unites States. The American cultural language, Long says, is the "misinterpretation" of humanness and freedom conveyed when the term "American"--used to signify…

  14. Psyllids as A Tool in Evaluating the Efficiency of Different Management Practices for Control of Citrus Huanglongbing Disease

    USDA-ARS?s Scientific Manuscript database

    Huanglongbing (HLB), or citrus greening disease, was found in Brazil in 2004. Two species of bacteria, Candidatus Liberibacter asiaticus and Ca. L. americanus, have been identified in Brazil. The disease has not been effectively managed anywhere in the world so far. This is probably because of long ...

  15. RELATIONSHIPS BETWEEN HABITAT QUALITY AND DENSITY OF JUVENILE WINTER FLOUNDER

    EPA Science Inventory

    We used a digital video camera mounted to a 1-m beam trawl together with an attached continuous recording YSI sonde and GPS unit to quantify juvenile winter flounder (Pseudopleuronectes americanus) densities and fish habitat. The YSI sonde measured temperature, salinity, dissolve...

  16. Carbon and nitrogen isotope ratios of juvenile winter flounder as indicators of inputs to estuarine systems

    EPA Science Inventory

    Stable carbon and nitrogen isotope ratios were measured in the muscle tissues of young-of-the-year (YOY) winter flounder, Pseudopleuronectes americanus, collected from several estuarine systems along the coast of Rhode Island, USA. These systems included three coastal lagoons (Ni...

  17. Oak-Black Bear Relationships in Southeastern Uplands

    Treesearch

    Joseph D. Clark

    2004-01-01

    Bears (Ursus americanus) primarily occur in upland habitats in the Southeast because uplands were the last to be developed for agriculture and were more likely to become publicly owned. National parks and forests created in the early to mid-1900s served as sources to supply surrounding uplands with bears. Bears could not survive in southeastern...

  18. Demography of snowshoe hares in relation to regional climate variabilty during a 10-year population cycle in interior Alaska

    Treesearch

    K. Kielland; K. Olson; E. Euskirchen

    2009-01-01

    We monitored populations of snowshoe hares (Lepus americanus, Erxleben) in interior Alaska for 10 years from 1999 to 2008. During this period, fall densities of hares fluctuated approximately 14-fold. High population growth rates over summer were followed by large population declines over winter. Young-of-the-year hares tended to gain mass over...

  19. Satellite monitoring of black bear.

    NASA Technical Reports Server (NTRS)

    Craighead, J. J.; Craighead, F. C., Jr.; Varney, J. R.; Cote, C. E.

    1971-01-01

    Description of a feasibility experiment recently performed to test the use of a satellite system for telemetering environmental and physiological data from the winter den of a 'hibernating' black bear, Ursus americanus. The instrumentation procedure and evaluations of the equipment performance and sensory data obtained are discussed in detail.

  20. Mapping landscape phenology preference of yellow-billed cuckoo with AVHRR data

    Treesearch

    Cynthia S. A. Wallace; Miguel Villarreal; Charles van Riper

    2013-01-01

    We mapped habitat for threatened Yellow-billed Cuckoo (Coccycus americanus occidentalis) in the State of Arizona using the temporal greenness dynamics of the landscape, or the landscape phenology. Landscape phenometrics were derived from Advanced Very High Resolution Radiometer (AVHRR) Normalized Difference Vegetation Index (NDVI) data for 1998 and 1999 by using...

  1. Diversity of frankia strains in root nodules of plants from the families elaeagnaceae and rhamnaceae

    PubMed

    Clawson; Caru; Benson

    1998-09-01

    Partial 16S ribosomal DNAs (rDNAs) were PCR amplified and sequenced from Frankia strains living in root nodules of plants belonging to the families Elaeagnaceae and Rhamnaceae, including Colletia hystrix, Elaeagnus angustifolia, an unidentified Elaeagnus sp., Talguenea quinquenervia, and Trevoa trinervis. Nearly full-length 16S rDNAs were sequenced from strains of Frankia living in nodules of Ceanothus americanus, C. hystrix, Coriaria arborea, and Trevoa trinervis. Partial sequences also were obtained from Frankia strains isolated and cultured from the nodules of C. hystrix, Discaria serratifolia, D. trinervis, Retanilla ephedra, T. quinquenervia, and T. trinervis (Rhamnaceae). Comparison of these sequences and other published sequences of Frankia 16S rDNA reveals that the microsymbionts and isolated strains from the two plant families form a distinct phylogenetic clade, except for those from C. americanus. All sequences in the clade have a common 2-base deletion compared with other Frankia strains. Sequences from C. americanus nodules lack the deletion and cluster with Frankia strains infecting plants of the family Rosaceae. Published plant phylogenies (based on chloroplast rbcL sequences) group the members of the families Elaeagnaceae and Rhamnaceae together in the same clade. Thus, with the exception of C. americanus, actinorhizal plants of these families and their Frankia microsymbionts share a common symbiotic origin.

  2. NEKTON HABITAT QUALITY AT SHALLOW-WATER SITES IN TWO RHODE ISLAND COASTAL SYSTEMS

    EPA Science Inventory

    We evaluated nekton habitat quality at five shallow-water sites in two Rhode Island systems by comparing nekton densities and biomass, number of species, prey availability and feeding, and abundance of winter flounder Pseudopleuronectes americanus. Nekton density and biomass wer...

  3. Development of high density SNP-based linkage map in pearl millet

    USDA-ARS?s Scientific Manuscript database

    Pearl millet (Cenchrus americanus (L.) Morrone) is a gluten free grain crop which is additionally gaining importance in the USA due to the increased demand for pearl millet flour by many ethnic groups. As a result, efforts are underway in the Southeast to develop high grain yielding adapted pearl mi...

  4. USING WINTER FLOUNDER GROWTH RATES TO ASSSESS HABITAT QUALITY IN RHODE ISLAND'S COASTAL LAGOONS

    EPA Science Inventory

    We used growth rates of juvenile winter flounder Pseudopleuronectes americanus, to assess habitat quality in 3 of Rhode Island's coastal salt ponds that had differing levels of nutrients and human development. In each pond, 1 m2 cages were placed in vegetated and unvegetated habi...

  5. A Case Study of the Effects of Dredging in Narrgansett Bay (RI, USA) on Winter Flounder Eggs

    EPA Science Inventory

    Seasonal dredging constraints have been established in several northeastern U.S. estuaries with the intent to protect winter flounder (Pseudopleuronectes americanus). A major source of concern is impacts on demersal eggs due to elevated sedimentation rates during the winter-earl...

  6. USE OF VIDEO TO ACCESS JUVENILE WINTER FLOUNDER DENSITIES AND HABITATS

    EPA Science Inventory

    We used a digital video camera mounted to a 1-m beam trawl together with an attached continuous recording YSI sonde and a GPS unit to quantify juvenile winter flounder (Pseudopleuronectes americanus) densities and fish habitat in Narragansett Bay, RI. The YSI sonde measured te...

  7. Genome sequence of Candidatus Liberibacter asiaticus, the casual agent of citrus huanglongbing (greening)

    USDA-ARS?s Scientific Manuscript database

    Citrus huanglongbing (HLB) is one of the most devastating diseases of citrus worldwide. The disease is associated with three different species of Candidatus Liberibacter: Ca. L. asiaticus (Las), Ca. L. americanus and Ca. L. africanus. We first detected and identified Las bacterium from HLB-infected...

  8. First Report of Dodder Transmission of Candidatus Liberibacter asiaticus to Tomato (Lycopersicon esculentum)

    USDA-ARS?s Scientific Manuscript database

    Huanglongbing (HLB) or “greening”, caused by the fastidious a-proteobacteria Candidatus Liberibacter asiaticus (Las), Ca. L. americanus (Lam) and Ca. L. africanus, is one of the most devastating diseases of citrus worldwide (1). Las was first detected in South Florida in 2005, and has spread throu...

  9. A unique disease phenotype -‘yellow shoot without blotchy mottle’ was associated with a low titer of Candidatus Liberibacter asiaticus in Florida

    USDA-ARS?s Scientific Manuscript database

    Citrus huanglongbing (HLB) is one of the most devastating diseases of citrus worldwide. The disease is associated with three different species of Candidatus Liberibacter: Ca. L. asiaticus, Ca. L. americanus and Ca. L. africanus. Ca. L. asiaticus (Las), first detected in Florida in 2005, has been d...

  10. [Cribra orbitalia (Porotic hyperostosis) in a prehistoric population of Parana Medio].

    PubMed

    Cornero, Silvia; Puche, Rodolfo C

    2002-01-01

    The observation of porotic hyperostosis in the orbits (criba orbitalia) in bone remains of a funeral site at the north of the Santa Fe province strongly suggests the occurrence of severe anemia among dwellers. Intestinal parasitosis (by Ancylostoma duodenalis or Necator americanus) is deemed the most likely cause of the anemia.

  11. ASSESSING HABITAT QUALITY OF MOUNT HOPE BAY AND NARRAGANSETT BAY USING GROWTH, RNA:DNA, AND FEDDING HABITS OF CAGED JUVENILE WINTER FLOUNDER

    EPA Science Inventory

    Somatic growth rates, RNA:DNA, and feeding habits of juvenile Pseudopleuronectes americanus (Winter Flounder) were used to asses small-scale spatio-temporal variations in the habitat quality of Mount Hope Bay and Narragan-sett Bay, RI. Three successive caging experiments (14–16 d...

  12. 75 FR 41432 - Trade Adjustment Assistance for Farmers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-16

    ... (No. 2010002) for trade adjustment assistance (TAA) for U.S. lobster (Homarus americanus) that was... to the decrease in one of the above factors for the agricultural commodity. All petitions were... data for the same time period showed a 1.1-percent decrease, rather than the required increase....

  13. Influence of precommercial thinning on snowshoe hares.

    Treesearch

    Evelyn L. Bull; Thad W. Heater; Abe A. Clark; Jay F. Shepherd; Arlene K. Blumton

    2005-01-01

    Relative abundance, survival, home range, and habitat use of snowshoe hares (Lepus americanus) were evaluated in five precommercial thinning treatments in lodgepole pine (Pinus contorta Dougl. ex Loud.) stands in northeastern Oregon between June 2000 and July 2003. A combination of track surveys, trapping grids, and...

  14. Supplemental Environmental Assessment & Finding of No Significant Impact: Louisville Bend State Wildlife Area Fish and Wildlife Habitat Rehabilitation

    DTIC Science & Technology

    2013-05-01

    Additionally, species of special concern, such as the endangered pallid sturgeon and the state endangered lake sturgeon ( Acipenser fulvescens ) have the...MONONA Ornate Box Turtle Terrapene ornata T 1971 MONONA Grass Pickerel Esox americanus T 2011 MONONA Lake Sturgeon Acipenser fulvescens E MONONA

  15. An examination of the genetic control of Douglas-fir vascular tissue phytochemicals: implications for black bear foraging.

    Treesearch

    Bruce A. Kimball; G.R. Johnson; Dale L. Nolte; Doreen L. Griffin

    1999-01-01

    Silvicultural practices can influence black bear (Ursus americanus) foraging preferences for Douglas-fir (Pseudotsuga menziesii) cambial-zone vascular tissues, but little is known about the role of genetics. To study the impact of genetic selection, vascular tissue samples were collected from Douglas-fir trees in six half-sib families from five...

  16. Very rapid long-distance sea crossing by a migratory bird

    NASA Astrophysics Data System (ADS)

    Alves, José A.; Dias, Maria P.; Méndez, Verónica; Katrínardóttir, Borgný; Gunnarsson, Tómas G.

    2016-11-01

    Landbirds undertaking within-continent migrations have the possibility to stop en route, but most long-distance migrants must also undertake large non-stop sea crossings, the length of which can vary greatly. For shorebirds migrating from Iceland to West Africa, the shortest route would involve one of the longest continuous sea crossings while alternative, mostly overland, routes are available. Using geolocators to track the migration of Icelandic whimbrels (Numenius phaeopus), we show that they can complete a round-trip of 11,000 km making two non-stop sea crossings and flying at speeds of up to 24 m s‑1 the fastest recorded for shorebirds flying over the ocean. Although wind support could reduce flight energetic costs, whimbrels faced headwinds up to twice their ground speed, indicating that unfavourable and potentially fatal weather conditions are not uncommon. Such apparently high risk migrations might be more common than previously thought, with potential fitness gains outweighing the costs.

  17. The Relationships between Morphological Characteristics and Foraging Behavior in Four Selected Species of Shorebirds and Water Birds Utilizing Tropical Mudflats

    PubMed Central

    Norazlimi, Nor Atiqah; Ramli, Rosli

    2015-01-01

    A study was conducted to investigate the relationship between the physical morphology of shorebirds and water birds (i.e., Lesser adjutant (Leptoptilos javanicus), Common redshank (Tringa totanus), Whimbrel (Numenius phaeopus), and Little heron (Butorides striata)) and their foraging behavior in the mudflats area of Selangor, Peninsular Malaysia, from August 2013 to July 2014 by using direct observation techniques (using binoculars and a video recorder). The actively foraging bird species were watched, and their foraging activities were recorded for at least 30 seconds for up to a maximum of five minutes. A Spearman Rank Correlation highlighted a significant relationship between bill size and foraging time (R = 0.443, p < 0.05), bill size and prey size (R = −0.052, p < 0.05), bill size and probing depth (R = 0.42, p = 0.003), and leg length and water/mud depth (R = 0.706, p < 0.005). A Kruskal-Wallis Analysis showed a significant difference between average estimates of real probing depth of the birds (mm) and species (H = 15.96, p = 0.0012). Three foraging techniques were recorded: pause-travel, visual-feeding, and tactile-hunting. Thus, morphological characteristics of bird do influence their foraging behavior and strategies used when foraging. PMID:26345324

  18. Very rapid long-distance sea crossing by a migratory bird

    PubMed Central

    Alves, José A.; Dias, Maria P.; Méndez, Verónica; Katrínardóttir, Borgný; Gunnarsson, Tómas G.

    2016-01-01

    Landbirds undertaking within-continent migrations have the possibility to stop en route, but most long-distance migrants must also undertake large non-stop sea crossings, the length of which can vary greatly. For shorebirds migrating from Iceland to West Africa, the shortest route would involve one of the longest continuous sea crossings while alternative, mostly overland, routes are available. Using geolocators to track the migration of Icelandic whimbrels (Numenius phaeopus), we show that they can complete a round-trip of 11,000 km making two non-stop sea crossings and flying at speeds of up to 24 m s−1; the fastest recorded for shorebirds flying over the ocean. Although wind support could reduce flight energetic costs, whimbrels faced headwinds up to twice their ground speed, indicating that unfavourable and potentially fatal weather conditions are not uncommon. Such apparently high risk migrations might be more common than previously thought, with potential fitness gains outweighing the costs. PMID:27901077

  19. The Relationships between Morphological Characteristics and Foraging Behavior in Four Selected Species of Shorebirds and Water Birds Utilizing Tropical Mudflats.

    PubMed

    Norazlimi, Nor Atiqah; Ramli, Rosli

    2015-01-01

    A study was conducted to investigate the relationship between the physical morphology of shorebirds and water birds (i.e., Lesser adjutant (Leptoptilos javanicus), Common redshank (Tringa totanus), Whimbrel (Numenius phaeopus), and Little heron (Butorides striata)) and their foraging behavior in the mudflats area of Selangor, Peninsular Malaysia, from August 2013 to July 2014 by using direct observation techniques (using binoculars and a video recorder). The actively foraging bird species were watched, and their foraging activities were recorded for at least 30 seconds for up to a maximum of five minutes. A Spearman Rank Correlation highlighted a significant relationship between bill size and foraging time (R = 0.443, p < 0.05), bill size and prey size (R = -0.052, p < 0.05), bill size and probing depth (R = 0.42, p = 0.003), and leg length and water/mud depth (R = 0.706, p < 0.005). A Kruskal-Wallis Analysis showed a significant difference between average estimates of real probing depth of the birds (mm) and species (H = 15.96, p = 0.0012). Three foraging techniques were recorded: pause-travel, visual-feeding, and tactile-hunting. Thus, morphological characteristics of bird do influence their foraging behavior and strategies used when foraging.

  20. Immunochemical and immunocytochemical studies of the crustacean vitellogenesis-inhibiting hormone (VIH).

    PubMed

    Meusy, J J; Martin, G; Soyez, D; van Deijnen, J E; Gallo, J M

    1987-09-01

    Immunochemical investigations, using dot immunobinding assay (DIA) and enzyme-linked immunosorbent assay (ELISA), and immunocytochemical studies reveal the following new information about crustacean vitellogenesis-inhibiting hormone (VIH): (1) The structure of VIH is sufficiently different from that of the other sinus gland neuropeptides to allow a selective recognition of VIH by polyclonal antibodies. (2) From immunochemical criteria, VIH does not seem strictly species specific. The antisera raised against VIH of Homarus americanus cross-react with sinus gland extracts of Palaemonetes varians, Palaemon serratus, Macrobrachium rosenbergii, Carcinus maenas, and Porcellio dilatatus. (3) In the sinus gland of H. americanus, VIH immunoreactivity is localized mainly in electron-dense granules of medium size (110-185 nm in diameter) while, in P. dilatatus, the labeling is mostly on the largest granules (200-270 nm in diameter).