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排序方式: 共有664条查询结果,搜索用时 31 毫秒
1.
Catherine Bradley Suresh Andrew Sethi Joshua Ashline Jonathon Gerken 《Ecology of Freshwater Fish》2017,26(4):695-706
In this study, we examined summer and fall freshwater rearing habitat use by juvenile coho salmon (Oncorhynchus kisutch) in the quickly urbanising Big Lake drainage in south‐central Alaska. Habitat use was assessed by regressing fish count data against habitat survey information across thirty study sites using generalised linear mixed models. Habitat associations were examined by age‐0 and age‐1+ cohorts separately, providing an opportunity to compare habitat use across different juvenile coho salmon life stages during freshwater rearing. Regression results indicated that the age‐0 cohorts were strongly associated with shallow, wide stream reaches with in‐stream vegetation, whereas age‐1+ cohorts were associated with deeper stream reaches. Furthermore, associations between fork length and habitat characteristics suggest cohort‐specific habitat use patterns are distinct from those attributable to fish size. Habitat use information generated from this study is being used to guide optimal fish passage restoration planning in the Big Lake drainage. Evidence for habitat use partitioning by age cohort during freshwater juvenile rearing indicates that pooling age cohorts into a single “juvenile” stage for the purposes of watershed management may mask important habitat use dynamics. 相似文献
2.
J O Joshua 《The Veterinary record》1975,96(14):300-302
An eruptive condition seen on certain mucous membranes of dogs occurs frequently but often asymptomatically. Lesions have been found to be present in over 60 percent of male dogs. The infection is probably due to a canine herpes virus and has been termed conveniently but inaccurately "dog pox". In many cases lesions are present without observable clinical signs but severe irritation, especially related to lesions in the lower bowel, can give rise to marked symptoms which may be confused with abnormality of the para-anal sacs, or to chronic diarrhoea of a type suggestive of colitis. The incidence, sites of infection and possible syndromes which may be ascribed to the condition are briefly discussed on a clinical basis only. 相似文献
3.
The ability to predict species occurrences quickly is often crucial for managers and conservation biologists with limited
time and funds. We used measured associations with landscape patterns to build accurate predictive habitat models that were
quickly and easily applied (i.e., required no additional data collection in the field to make predictions). We used classification
trees (a nonparametric alternative to discriminant function analysis, logistic regression, and other generalized linear models)
to model nesting habitat of red-naped sapsuckers (Sphyrapicus nuchalis), northern flickers (Colaptes auratus),tree swallows (Tachycineta bicolor), and mountain chickadees (Parus gambeli) in the Uinta Mountains of northeastern Utah, USA. We then tested the predictive capability of the models with independent
data collected in the field the following year. The models built for the northern flicker, red-naped sapsucker, and tree swallow
were relatively accurate (84%, 80%, and 75% nests correctly classified,respectively)compared to the models for the mountain
chickadee (50% nests correctly classified). All four models were more selective than a null model that predicted habitat based
solely on a gross association with aspen forests. We conclude that associations with landscape patterns can be used to build
relatively accurate, easy to use, predictive models for some species. Our results stress, however, that both selecting the
proper scale at which to assess landscape associations and empirically testing the models derived from those associations
are crucial for building useful predictive models.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
4.
Abdilatif Mohamed Haji Onono Joshua Orungo Mutua Florence Kanini 《Tropical animal health and production》2018,50(7):1701-1710
Tropical Animal Health and Production - Small ruminants’ production contributes to livelihood of pastoral communities, but this faces myriad constraints. This study aimed at identifying... 相似文献
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7.
Vertebrata lanosa is a red alga that can commonly be found along the shores of Europe and North America. Its composition of bromophenols has been studied intensely. The aim of the current study was therefore to further investigate the phytochemistry of this alga, focusing more on the polar components. In total, 23 substances were isolated, including lanosol-4,7-disulfate (4) and the new compounds 3,5-dibromotyrosine (12), 3-bromo-5-sulfodihydroxyphenylalanine (13), 3-bromo-6-lanosyl dihydroxyphenylalanine (14), 3-(6′-lanosyl lanosyl) tyrosine (15) and 5-sulfovertebratol (16). In addition, 4-sulfo-7-dimethylsulfonium lanosol (7) was identified. While, in general, the dimethylsulfonium moiety is widespread in algae, its appearance in bromophenol is unique. Moreover, the major glycerogalactolipids, including the new ((5Z,8Z,11Z,14Z,17Z)-eicosapentaenoic acid 3′-[(6′’-O-α-galactopyranosyl-β-D-galactopyranosyl)]-1-glycerol ester (23), and mycosporine-like amino acids, porphyra-334 (17), aplysiapalythine A (18) and palythine (19), were identified. 相似文献
8.
Characterization of ileal bacterial microbiota in newly-weaned pigs in response to feeding lincomycin, organic acids or herbal extract 总被引:1,自引:1,他引:1
Joshua Gong Hai Yu Ting Liu Mei Li Weiduo Si Cornelis F.M. de Lange Cate Dewey 《Livestock Science》2008,116(1-3):318-322
The changes of ileal bacterial microbiota in pigs during the first 2 weeks post-weaning in response to feeding lincomycin, organic acids or herbal extract were characterized using 16S rRNA gene-based PCR-denaturing gradient gel electrophoresis (DGGE) profiling, DNA sequencing, and real-time PCR (QPCR) techniques. Both time post-weaning and the dietary treatments resulted in a shift of the microbiota composition. While time post-weaning mostly influenced Clostridium group, the feed additives increased the population of Lactobacillus and related lactic acid bacteria by ≥ 3-fold. 相似文献
9.
Josephine A. Dornbusch Laura E. Selmic Pin‐Chieh Huang Jonathan P. Samuelson Eric M. McLaughlin Vincent A. Wavreille Jessica A. Ogden Brittany Abrams Alex Kalamaras Eric Green Eric T. Hostnik Lincoln Every Jason A. Fuerst Ryan Jennings Christopher Premanandan Joshua N. Lorbach Sarah C. Linn Aneesh Alex Janet E. Sorrells Lingxiao Yang Stephen A. Boppart 《Veterinary surgery : VS》2021,50(1):111-120
10.
Factors affecting the success rate of treatment of recumbent dairy cows suffering from hypocalcaemia
Gelfert CC Alpers I Dallmeyer M Decker M Hüting A Lesch S Baumgartner W Staufenbiel R 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2007,54(4):191-198
We aimed to investigate the ratio of accompanying diseases in cows suffering from clinical hypocalcaemia and their influence on cure rate. In five veterinary practices in different regions of Germany, all recumbent cows around parturition were included in the study for a period of 1 year. After recording the case history a clinical examination was done and a serum sample was taken to measure the concentrations of calcium and phosphorus magnesium, beta-hydroxybutyrate, total bilirubin, cholesterol, urea, and the activities of ASAT, CK, and GLDH. Only cows with hypocalcaemia entered the statistical analysis. Hypocalcaemia was the major cause of recumbency in cows of the second lactation or elder. Muscle damage was the second frequent diagnose in recumbent cows and the major concomitant disease in hypocalcaemic cows. The overall cure rate was between 89.4% and 94.8%. Calcium and phosphorus concentrations did not have an influence on cure rate. Non-cured cows had higher serum activities of CK (p<0.043) and ASAT (p<0.006). Nevertheless, the activities of CK and ASAT were no good predictors of treatment failure because of their low specificity and the high cure rate of the cows in the five practices. 相似文献