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171.
172.
R. G. Cooper Kh. M. A. Mahrose J. O. Horbańczuk R. Villegas-Vizcaíno S. Kennou Sebei A. E. Faki Mohammed 《Tropical animal health and production》2009,41(8):1669-1678
The aim of the current report was to study the literature pertinent to wild populations of ostriches and their ecological
and behavioural adaptations in the wild. Selected areas included palaeontology; ostrich distribution; conservation status
and relationships with humans and habitat. There is an immediate and urgent need to conserve and protect the apparently rapidly
declining populations of wild ostriches with the committed involvement of governments and funding bodies. Wildlife management
is an important complement to the farming of livestock. Scientists need to understand the elements of ostrich behaviour in
the wild in order to make informed decisions on their management and contact with other animals. Information of the like should
be included in readily-accessible and annually updated wildlife manuals. We deemed that such information was an essential
part in the conservation of this dwindling ratite. 相似文献
173.
Lushani Nanayakkara Elizabeth R. Starks Ryan N. Cooper Sydney Chow Peter R. Leavitt Björn Wissel 《Fisheries Management and Ecology》2021,28(1):18-27
This study evaluated the status of native and stocked fish species in 13 prairie lakes in central Canada over eight years (2007–14) using three metrics: resource-use (benthic versus pelagic carbon via stable isotopes); body condition (relative weight index Wr); and parasite load (cestode gut enumerations). Analyses included game and non-game fishes, like naturally occurring northern pike, Esox lucius L., and yellow perch, Perca flavescens Mitchill, but focused on stocked walleye, Sander vitreus (Mitchill) because it supports a robust recreational fishery. Walleye and northern pike were significantly more reliant on benthic carbon than yellow perch or forage fishes (p < 0.05), but this reliance was not associated with any measured environmental variables for any species. In lakes with game fishes, forage fishes exhibited higher reliance on benthic energy, possibly due to predator avoidance strategy, particularly yellow perch. Walleye body condition index was consistently lower (<95–105) than values exhibited by the other two game fishes (81–139), and parasites were only common in walleye and associated with lake-water salinity (r2 = 0.93, p < 0.05) and sex (p < 0.05). Based on the results, the most desirable game fish, walleye, appears less resilient to environmental variability than northern pike and yellow perch, making this species more susceptible to impacts of future climate change. 相似文献
174.
Forest riparian buffers are an important means of conserving land. The Conservation Reserve Enhancement Program (CREP) offers
financial incentives to landowners to install forested riparian buffers under 10–15 year contracts. This study explores whether
Pennsylvania CREP participants who had established a riparian buffer would also place it under a permanent conservation easement.
A mail questionnaire was developed and administered to 685 CREP participants. It was found that the majority of the respondents
are likely to leave their buffer intact when the CREP contract expires, but are hesitant to agree to conservation easements.
Property rights, education and finances are among the key issues affecting acceptance of conservation easements. 相似文献
175.
Validation of the BioPRYN enzyme‐linked immunosorbent assay for detection of pregnancy‐specific protein‐B (PSPB) and diagnosis of pregnancy in American bison (Bison bison)
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This study assessed the accuracy of the commercial BioPRYN® ELISA for the detection of pregnancy‐specific protein‐B (PSPB) using a single blood sample to determine pregnancy status in American bison (Bison bison). A total of 49 bison cows were used in the study, and sampled at two time‐points during the gestation period, fall and spring, correlating with early‐ to mid‐term gestation (average 62.9 days post‐mating) and mid‐ to late‐term gestation (average 229.2 days post‐mating), respectively. Sensitivity of the test during early‐ to mid‐term gestation sampling period (fall) was 87.1%, while specificity was 100%; sensitivity of the test during late‐term gestation sampling period (spring) was 96.3%, while specificity remained at 100%. In total, the test showed a total sensitivity of 91.4%, specificity of 100% and total accuracy of 93.8%, similar to domestic cattle. Use of the single‐sample BioPRYN® ELISA in American Bison for pregnancy diagnosis is economical and practical, minimizing animal handling time, frequency and subsequent stress while providing accurate results for pregnancy diagnosis at 62 days post‐mating. This method should be considered over more traditional pregnancy diagnosis methods for use in managed bison herds. 相似文献
176.
177.
Ross G. Cooper Jaroslaw O. Horbańczuk Raul Villegas-Vizcaíno Salwa Kennou Sebei Aisha E. Faki Mohammed Khalid M. A. Mahrose 《Tropical animal health and production》2010,42(3):363-373
This work discusses some of the important considerations of wild ostrich evolution, behaviour and ecology, as items included
in ostrich production. In the process considerable research was conducted by collating information from peer-reviewed papers;
textbooks; manuals; and PubMed and Agricola searches. Selected areas reviewed included activity of ostriches; feeding and
water needs; sexual maturity; egg laying and natural incubation; selected physiological parameters; and predation. There is
an immediate and urgent need to conserve and protect the rapidly declining populations of wild ostriches with the committed
involvement of governments and funding bodies. 相似文献
178.
Sentíes-Cué CG Charlton BR Woolcock P Bickford AA Cooper G Bland M 《Avian diseases》2010,54(4):1316-1318
An unusual cutaneous fowl pox outbreak occurred in 8-wk-old broilers in California. Rounded and longitudinal, proliferative scratch-associated lesions were found only in feathered areas of the body. Both sides of the hip, the lower abdomen, pericloacal area, and lateral lower neck area were involved. The head, legs, feet, and toes did not have lesions. Birds in only one section of one of five houses were affected. Fifteen percent condemnations occurred in birds from the affected house due to the skin lesions. A diagnosis of fowl pox was achieved by histopathology, viral isolation, and direct electron microscopy. The unusual distribution of pox lesions was assumed to be associated with skin scratches. There was no evidence that mosquitoes or other types of insects were involved in this outbreak. To the knowledge of the authors, this is the first report of this kind of unusual fowl pox in the United States. 相似文献
179.
180.