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101.
102.
Pyogranulomatous panniculitis in a cat associated with infection by the Mycobacterium fortuitum/peregrinum group 下载免费PDF全文
Youssef S Archambault M Parker W Yager J 《The Canadian veterinary journal. La revue veterinaire canadienne》2002,43(4):285-287
A 6-year-old, spayed female, American domestic shorthair was presented with a 10-month history of nodules on the dorsum. Diagnosis of pyogranulomatous panniculitis caused by Mycobacterium fortuitum/peregrinum group was achieved by using tissue culture, chromatography, and histopathologic examination. Pathological findings, diagnosis, and clinical management of the condition are discussed. 相似文献
103.
Antimicrobial use through feed, water, and injection in 20 swine farms in Alberta and Saskatchewan 下载免费PDF全文
Leigh B. Rosengren Cheryl L. Waldner Richard J. Reid-Smith John C.S. Harding Sheryl P. Gow Wendy L. Wilkins 《Canadian journal of veterinary research》2008,72(2):143-150
Antimicrobial resistance (AMR) is an emerging animal welfare and public health issue linked to antimicrobial use (AMU) in livestock. This study was conducted in 2004 on 20 swine farms in Alberta and Saskatchewan. On-farm records and questionnaires were used to retrospectively describe the antimicrobial exposures of pigs through feed, water, and injection. Antimicrobial use in all production categories was described over 12 months. On-farm records and questionnaires provided sufficient data to describe antimicrobial exposure rates through feed and water. In contrast, on-farm records did not supply sufficient data to describe parenteral antimicrobial exposure rates. Records lacked data on the number of exposures per treatment, therefore parenteral AMU was described as an exposure incidence. Parenteral exposure records were often unavailable for pigs less than 22 kg, in which case questionnaires were used. The incidence of parenteral AMU was significantly higher in herds reporting exposure by questionnaire compared with existing records, suggesting that on-farm records did not reliably describe parenteral AMU. However, because antimicrobial exposures in feed and water were markedly more common than through injection, it was concluded that existing on-farm data would be a valuable resource for investigating AMU and AMR in pigs. 相似文献
104.
Najiah M Nadirah M Lee KL Lee SW Wendy W Ruhil HH Nurul FA 《Veterinary research communications》2008,32(5):377-381
Slipper oyster Crassostrea iredalei is a species of good demand for its sweet flavor and white coloured flesh. The filter feeding nature predisposes oysters
to accumulation of pathogenic and heavy metals in waters impacted by sewage pollutions and may thus render the oysters unfit
for human consumption. A study was undertaken to investigate the presence of bacteria flora and heavy metal concentrations
in cultivated oysters Crassostrea iredalei at Setiu Wetland, Terengganu, the only source of cultivated oysters in East Coast of Malaysia. A total of 200 slipper oyster
samples were analyzed. The bacteria were isolated using non selective agar such as TSA agar and selective agars before they
were then identified using conventional methods in combination with BBL Crystal identification kit. Heavy metals such as zinc
(Zn), copper (Cu), cadmium (Cd), and lead (Pb) concentrations were determined using atomic absorption spectrophotometry. Results
showed that the oysters harbor predominantly Shewanella putrifaciens followed by Vibrio parahaemolyticus, Vibrio vulnificus, Vibrio cholerae, Enterobacter cloacae, Escherichia coli and Chromobacterium violaceum. They also contain high concentration of Zn (785.68 ± 285.88 μg/g) with the lowest heavy metal was Pb (0.17 ± 0.15 μg/g),
whilst the concentrations of other heavy metals were Cu (38.9 ± 13.2 μg/g) and Cd (1.60 ± 0.28 μg/g). The study is very useful
to evaluate the type of bacteria and heavy metal present in oyster meat for human consumption. 相似文献
105.
Ten 56-d-old, 15-kg barrows were surgically fitted with a postvalvular T-cecum cannula at the ileo-cecal junction to evaluate the effect of microbial phytase on apparent and true ileal AA digestibility and N utilization. A semipurified cornstarch- and soybean meal-based diet was formulated to contain 3.4 Mcal of DE/kg, 17.0% CP, 0.8% Ca, and 0.6% P but had a low phytate-P concentration (0.13%; all on an as-fed basis). Chromic oxide and dysprosium chloride were used as indigestible markers. The basal diet was supplemented with 0 or 1,000 phytase units/kg of microbial phytase. Postprandial plasma urea N and alpha-amino N concentrations, excretion of Ca, P, and N in feces and urine, and ileal AA digestibilities were determined 3 times at 4-wk intervals beginning at 70 d of age. The homoarginine (HA) method was used to determine endogenous AA flow by replacing 50% of the basal protein with guanidinated protein. Microbial phytase had no effect on apparent ileal digestibility (AID) or on true ileal digestibilities of N and most AA but did increase AID for arginine (P = 0.006) and methionine (P = 0.037). However, in HA diets, phytase increased the AID of CP (P = 0.01) and several AA. Addition of microbial phytase had no effect on the postprandial alpha-amino N concentrations in plasma but increased overall plasma urea N concentrations (P = 0.035). Barrows fed phytase-supplemented diets had decreased P in feces (P = 0.003) and greater P in urine (P = 0.001) but comparable total P excretion compared with barrows fed no phytase-supplemented diets. In conclusion, the addition of phytase to a semi-purified soybean meal-based diet did not affect the AID of several AA. In addition, differences between the basal and HA diets in N digestibilities indicated that that guanidination may limit the use of the HA method in determining endogenous protein losses. 相似文献
106.
Forage evaluation indices are available to assist farmer decision-making on the most appropriate ryegrass cultivars to grow. However, these indices currently take no account of any feeding value trait that reflects the interaction between the animal and the structural and morphological characteristics of the pasture. Information on the feeding value of ryegrass cultivars can be confounded by nutritive value, arising from the relationship between nutritive value and heading date. The objective of this study was to determine the milk production response of dairy cows grazing four perennial ryegrass diploid cultivars: two morphologies within two different heading dates and on three occasions during lactation across two years: late spring, summer and autumn. No consistent phenotypic effect occurred on milk production across the two years. Milk production responses were more closely aligned to energy intake. The sward structure changed physiologically from year 1 to year 2, with a reduction in the ratio of leaf to stem and subsequent increase in stem mass in year 2. Despite this, the relative difference in leaf to stem between mid-season and late-season heading dates remained consistent between years and had no effect on milk production. In one year, the apparent dry-matter intake was higher but it was not possible to determine which sward structure traits or group of traits contributed to this response. We conclude that, at this time, the evidence is insufficient to support inclusion of a phenotypic trait as represented by “feeding value” in forage evaluation indices. 相似文献
107.
Song Yang Shao-wei Zhai Brian S. Shepherd Fred P. Binkowski Silas S.O. Hung Wendy M. Sealey Dong‐Fang Deng 《Aquaculture Nutrition》2019,25(6):1171-1182
Two 3‐week growth trials were performed to determine the optimum feeding rate of juvenile lake sturgeon (Acipenser fulvescens) fed with a semi‐purified dry diet (protein, 440 g; lipid, 130 g/kg) at different feeding rates: 5, 10, 20, 30, and 40 g/kg body weight per day (BW/.d‐1), for 36 g‐sized fish; and 2.5, 5, 10, 20, and 30 g/kg BW/.d‐1, for 80 g sized fish. Feeding rates significantly influenced growth performances, feed conversion ratio, wholebody lipid and moisture contents, energy and protein retention, and fasted blood glucose levels (p < 0.05). The ratio of total C/total N measured in whole fish was positively correlated to the feeding rates and the lipid contents of whole fish. Suboptimal feeding significantly depressed growth performance and protein synthesis based on the measurement of RNA/DNA ratio in white muscle. Based on polynomial regression models, an optimal feeding rate to support the maximum growth, protein and energy retention was 34.5, 22 and 27.3 g/kg BW/.d‐1, respectively, for fish sized at 36–72 g; and 29.0, 16.9 and 19.9 g/kg BW/.d‐1, respectively for fish sized at 80–140 g. Results of this study will benefit future research to develop practical feeds to replace frozen live feed and feed management for lake sturgeon. 相似文献
108.
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110.
Paul Arens Theo van der Sluis Wendy P. C. van’t Westende Ben Vosman Claire C. Vos Marinus J. M. Smulders 《Landscape Ecology》2007,22(10):1489-1500
We studied the effects of landscape structure, habitat loss and fragmentation on genetic differentiation of Moor frog populations
in two landscapes in The Netherlands (Drenthe and Noord-Brabant). Microsatellite data of eight loci showed small to moderate
genetic differentiation among populations in both landscapes (F
ST values 0.022 and 0.060, respectively). Both heterozygosity and population differentiation indicate a lower level of gene
flow among populations in Noord-Brabant, where populations were further apart and have experienced a higher degree of fragmentation
for a longer period of time as compared to populations in Drenthe. A significant isolation-by-distance pattern was found in
Drenthe, indicating a limitation in dispersal among populations due to geographic distance. In Noord-Brabant a similar positive
correlation was obtained only after the exclusion of a single long-time isolated population. After randomised exclusion of
populations a significant additional negative effect of roads was found but not of other landscape elements. These results
are discussed in view of improving methodology of assessing the effects of landscape elements on connectivity.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献