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81.
Ten-week experiment was carried out on Japanese sea bass (5.87 ± 0.02 g) to study the effects of replacement of fish oil with six alternative lipid sources: pork lard, PL; beef tallow, BT; poultry fat, PF; soybean oil, SO; corn oil, CO; and a mixed-fat (MF: tallow, 60%; soy oil, 20%; fish oil, 20%) on growth performance and fatty acid (FA) composition in fillet and liver. Seven isoenergetic and isonitrogenous experimental diets were formulated, containing 10% of added lipid. Fish oil was used in control diet, which was substituted by 50% with the alternative lipid sources in the other six diets.

Weight gain (WG), specific growth rate (SGR), Feed conversion ratio (FCR) feed intake and hepatosomatic index (HSI) of fish fed the experimental diets were not significantly different (P > 0.05). Protein efficiency ratio (PER) in fish fed the PF diet were significantly lower than those of fish fed SO and CO diets. Significant differences in carcass moisture and lipid contents of carcass and liver were observed among fish fed the dietary treatments. Generally, the fatty acid composition of fish fillets and livers reflected the dietary FA composition.  相似文献   

82.
为获得能在肌肉表达绿色荧光蛋白的转基因斑马鱼(Brachydaniorerio),采用PCR方法,从斑马鱼基因组DNA中分离了肌球蛋白轻链2启动子,序列分析表明,该启动子与国外文献报道的斑马鱼肌球蛋白轻链2启动子序列的相似性为98.6%。将改造后的启动子插入绿色荧光蛋白基因载体,构建成肌肉特异性表达载体。通过显微注射,将线性化的表达载体注入斑马鱼的受精卵,获得了转绿色荧光蛋白基因的斑马鱼。绿色荧光蛋白在胚胎期开始表达,随着鱼体的生长表达量有增加的趋势,成鱼在紫外灯下用肉眼即可观察到绿色荧光。转基因鱼绿色荧光蛋白的表达具有明显的肌肉特异性。本研究为下一步特定基因的表达研究和获得有特色的转基因观赏鱼奠定了基础。  相似文献   
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In order to assess the seroprevalence of canine neosporosis 651 blood samples were collected from 586 household, 41 herding and 24 stray dogs, at small animal clinics in four large cities and other places of Hungary. Nineteen (2.9%) showed positivity in the IFAT with titres between 1:80 and 1:10240. Two dogs with high titres of antibodies to Neospora caninum had neuromuscular signs (imbalance, tremor) and a further one developed papulomatous, ulcerative and necrotizing dermatitis. There was no correlation between titers and age, sex, breed or keeping place. Although more male dogs had antibodies to N. caninum than females in case of both household and herding dogs, this association was not significant. No breed predisposition was observed. However, dogs with seroconversion were significantly more prevalent among rural (6%) than among urban dogs (1%), indicating that dogs in the countryside may have contact with or access to potentially infected offal from cattle and other intermediate hosts more frequently than those in large cities. Furthermore, significantly more herding dogs (29.3%) had antibodies to N. caninum than household dogs (1.2%), confirming the association between the occurrence of neosporosis and dog keeping on farms. The 12 dogs found seropositive among herding ones lived on 6 farms, on 5 of which seropositive cattle were also identified. This is the first report on the prevalence of N. caninum infection in dogs in Hungary.  相似文献   
85.
A two-year-old male ferret (Mustela putorius furo) was presented to the Faculty of Veterinary Science, Szent István University, for investigation of somnolence. Following unsuccessful therapeutic attempts, the ferret was euthanased and a male Dirofilaria immitis worm was found in the pulmonary artery and a female D. immitis specimen in the subdural space of the cranial cavity. To the authors’ knowledge, this is the first European record of D. immitis infection in a ferret, and the first case in which aberrant larval migration and consequent central nervous system signs were observed in a ferret in the course of D. immitis infection.  相似文献   
86.
Salmonella Heidelberg and Salmonella Typhimurium are among the most common serotypes responsible for human salmonellosis in Ontario. Introduction of the Ontario Investigation Tools (OIT) in 2014 allowed for standardized case investigation and reporting. This study compared the risk factors and symptomatology for sporadic S. Heidelberg and S. Typhimurium cases reported in Ontario in 2015, following implementation of the OIT. Multilevel logistic regression models were applied to assess associations between serotype and individual‐level demographic characteristics, exposures and symptoms for sporadic confirmed cases of S. Heidelberg and S. Typhimurium in Ontario in 2015. There were 476 sporadic cases of S. Typhimurium (n = 278) and S. Heidelberg (n = 198) reported in Ontario in 2015. There were significant associations between the odds of the isolate from a case being one of these serotypes, and travel, consumption of sprouts (any type), contact with reptiles and development of malaise, fever or bloody diarrhoea. The S. Typhimurium and S. Heidelberg cases differed in both symptom presentation and risk factors for illness. Case–case comparisons of Salmonella serotypes have some advantages over case–control studies in that these are less susceptible to selection and recall bias while allowing for rapid comparison of cases to identify potential high‐risk exposures that are unique to one of the serotypes when compared to the other. Comparing cases of two different Salmonella serotypes can help to highlight risk factors that may be uniquely associated with one serotype, or more strongly associated with one serotype compared to another. This information may be useful for understanding relative source attribution between common serotypes of Salmonella.  相似文献   
87.
Equine granulocytic anaplasmosis (EGA) and Lyme borreliosis (LB) are an emerging concern in Canada. We estimated the seroprevalence of EGA and equine LB by testing 376 convenience serum samples from 3 provinces using a point-of-care SNAP® 4Dx® ELISA (IDEXX Laboratories, Westbrook, Maine, USA), and investigated the agreement between the point-of-care ELISA and laboratory-based serologic tests. The estimated seroprevalence for EGA was 0.53% overall (0.49% in Saskatchewan, 0.71% in Manitoba), while the estimated seroprevalence for LB was 1.6% overall (0.49% in Saskatchewan, 2.86% in Manitoba). There was limited agreement between the point-of-care ELISA and an indirect fluorescent antibody test for EGA (kappa 0.1, PABAK 0.47) and an ELISA/Western blot combination for LB (kappa 0.23, PABAK 0.71). While the SNAP® 4Dx® ELISA yielded expected seroprevalence estimates, further evaluation of serologic tests for the purposes of disease exposure recognition may be needed.  相似文献   
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