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51.
Happy Birthday Geoff Sumner-Smith from all your friends and colleagues around the world!: Laudation.
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Benjamin A. Geaumont Torre J. Hovick Ryan F. Limb Wyatt M. Mack Amanda R. Lipinski Kevin K. Sedivec 《Strength and Conditioning Journal》2019,72(2):374-384
Native colonial and large ungulate herbivores infrequently coexist on contemporary landscapes but frequently would have in the past, and understanding these interactions is important for conservation in working landscapes—those lands managed for biological and economic objectives. Although many factors contribute to grassland bird declines, consistent and long-term removal of native herbivores from western grasslands promotes homogenous landscapes that are now uniformly grazed by cattle (Bos taurus). This shift in grassland disturbance patterns limits habitat availability for specialized grassland species. We investigated vegetation and bird community dynamics in pastures grazed by domestic cattle and a native colonial herbivore, the black-tailed prairie dog (Cynomys ludovicianus). The study occurred in the northern mixed-grass prairie of the United States on four experimental pastures stratified by the proportion of prairie dog occupancy to create an ecological gradient. Vegetation and bird surveys were conducted from 2012 to 2015 on and off prairie dog colonies. Vegetation and bird communities were not different along the experimental pasture gradient but did differ relative to location on versus off town. Prairie dogs induced changes in the plant community with midstatured grasses like side-oats grama (Bouteloua curtipendula) and green needlegrass (Nassella viridula) being associated with off-colony sites while on-colony sites were associated with disturbance-tolerant species such as fetid marigold (Dyssodia papposa). The bird community responded to changes in vegetation structure resulting from prairie dogs with grasshopper sparrows (Ammodramus savannarum) being more abundant off colonies in areas with greater vegetation structure, while bird species with more complex life histories, such as the upland sandpiper (Bartramia longicauda), were associated with both on ? and off ? prairie dog colonies. Our findings demonstrate the importance of maintaining spatial heterogeneity in working landscapes and show that native colonial herbivores can help achieve this in the presence of herbivory by domestic cattle. 相似文献
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Rhaony Gonalves Leite Elider Prates Romanzini Lutti Maneck Delevatti Alvair Hoffmann Adriana Cristina Ferrari Andr Pastori D'Aurea Lauriston Bertelli Fernandes Amanda Prates Oliveira Ricardo Andrade Reis 《Animal Science Journal》2019,90(5):628-636
Organic additives are recently being used in animal diets owing to their ability to control metabolic issues and result in better animal performance. Specifically, the organic additive Fator P® presents an additional advantage that is to cause a lesser greenhouse gas emission. This study evaluated whether Fator P® intake changes ruminal parameters or animal performance of beef cattle. Evaluations were carried out in a feedlot experiment divided into growing (46 days; two diets [control mix—CM and standard mix—SM] and finishing (lasted 83 days; four diets: CM, SM, Fator P® + virginiamycin, and Fator P® alone [FP]) trials. Animal performance study involved 48 animals allocated to 12 collective pens in completely randomized experimental design. Ruminal parameters were evaluated in separate metabolism study developed carried out using individual pen with four steers. During growing trial, FP diet resulted in higher (p < 0.05) dry matter intake (DMI) and ruminating time. In the finishing trial, diets containing Fator P® resulted in higher DMI than obtained with CM. Most of the ruminal parameters did not differ (p > 0.05) among dietary treatments. Therefore, Fator P® represents a viable and safe strategy for supplementation to beef cattle finished using high‐concentrate diet in feedlot systems. 相似文献
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Lauren Bookbinder Carrie J. Finno Anna M. Firshman Scott A. Katzman Erin Burns Janel Peterson Anna Dahlgren Brittni Ming‐Whitfield Shelby Glessner Amanda Borer‐Matsui Stephanie J. Valberg 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2019,33(6):2770-2779
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Alejandra M. Toro Ospina Amanda Marchi Maiorano Rogrio A. Curi Guilherme L. Pereira Maria Eugenia Zerlotti‐Mercadante Joslaine Noely dos Santos Gonalves Cyrillo Rusbel R. Aspilcueta‐Borquis Josineudson A. II de V. Silva 《Reproduction in domestic animals》2019,54(12):1524-1531
Linkage disequilibrium (LD) plays an important role in genomic selection and mapping of quantitative trait loci (QTL). This study investigated the pattern of LD and effective population size (Ne) in Gir cattle selected for yearling weight. For this purpose, 173 animals with imputed genotypes (from 18 animals genotyped with the Illumina BovineHD BeadChip and 155 animals genotyped with the Bovine LDv4 panel) were analysed. The LD was evaluated at distances of 25–50 kb, 50–100 kb, 100–500 kb and 0.5–1 Mb. The Ne was estimated based on 5 past generations. The r2 values (a measure of LD) were, respectively, .35, .29, .18 and .032 for the distances evaluated. The LD estimates decreased with increasing distance of SNP pairs and LD persisted up to a distance of 100 kb (r2 = .29). The Ne was greater in generations 4 and 5 (24 and 30 animals, respectively) and declined drastically after the last generation (12 animals). The results showed high levels of LD and low Ne, which were probably due to the loss of genetic variability as a consequence of the structure of the Gir population studied. 相似文献
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Mark D Bennett Lucy Woolford Philip K Nicholls Kristin S Warren Amanda J O'Hara 《Journal of veterinary diagnostic investigation》2008,20(3):376-379
The western barred bandicoot, Perameles bougainville, is an endangered Australian marsupial species. Routine histology of liver samples collected at necropsy from 19 of 20 (95%) western barred bandicoots revealed the sporadic to common occurrence of abnormal hepatocyte nuclei characterized by margination of chromatin and concomitant central pallor. Some abnormal hepatocyte nuclei were mildly to markedly enlarged and irregularly shaped. Periodic acid-Schiff reagent stained 131 of 142 (92%) of these abnormal hepatocyte nuclei. Positive staining was completely eliminated by diastase pretreatment. Transmission electron microscopy revealed that abnormal hepatocyte nuclei with marginated chromatin did not contain viral particles. Rather, glycogen beta-particles and alpha-rosettes were identified within some abnormal hepatocyte nuclei. Glycogen intranuclear inclusions were an incidental finding in western barred bandicoot hepatocytes. 相似文献
60.
Holly J Haefele Amanda Guthrie John G Trupkiewicz Michael M Garner 《Journal of zoo and wildlife medicine》2008,39(2):266-269
A neonatal male sable antelope (Hippotragus niger) was found dead. A 5 by 12-cm lobulated mass was present in the oral cavity, attached to the caudal border of the soft palate; this mass contained hair, cartilage, bone, nervous tissue, muscle, and multiple gland-like structures. Histopathologic diagnosis was consistent with oropharyngeal teratoma. As a result of the lack of wear of the fetal hooves, the firm, collapsed appearance of the lungs, and the lack of other gross or histopathologic abnormalities, the oropharyngeal tumor is suspected to have caused an airway obstruction, resulting in the calf's early postnatal death. This is the first report of an oropharyngeal teratoma in the veterinary literature. 相似文献