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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
961.
962.
Arias M Yeargan M Francisco I Dangoudoubiyam S Becerra P Francisco R Sánchez-Andrade R Paz-Silva A Howe DK 《Veterinary parasitology》2012,185(2-4):301-304
Horses serve as an intermediate host for several species of Sarcocystis, all of which utilize canids as the definitive host. Sarcocystis spp. infection and formation of latent sarcocysts in horses often appears to be subclinical, but morbidity can occur, especially when the parasite burden is large. A serological survey was conducted to determine the presence of antibodies against Sarcocystis spp. in seemingly healthy horses from the Galicia region of Spain. Western blot analyses using Sarcocystis neurona merozoites as heterologous antigen suggested greater than 80% seroprevalance of Sarcocystis spp. in a sample set of 138 horses. The serum samples were further tested with enzyme-linked immunosorbent assays (ELISAs) based on recombinant S. neurona-specific surface antigens (rSnSAGs). As expected for horses from the Eastern Hemisphere, less than 4% of the serum samples were positive when analyzed with either the rSnSAG2 or the rSnSAG4/3 ELISAs. An additional 246 horses were tested using the rSnSAG2 ELISA, which revealed that less than 3% of the 384 samples were seropositive. Collectively, the results of this serologic study suggested that a large proportion of horses from this region of Spain are exposed to Sarcocystis spp. Furthermore, the anti-Sarcocystis seroreactivity in these European horses could be clearly distinguished from anti-S. neurona antibodies using the rSnSAG2 and rSnSAG4/3 ELISAs. 相似文献
963.
F.O. Opapeju M. Rademacher R.L. Payne D.O. Krause C.M. Nyachoti 《Livestock Science》2010,131(1):58-64
Forty piglets (average body weight = 5.32 kg) were used to investigate the effect of dietary crude protein (CP) content on immunological responses following a challenge with enterotoxigenic Escherichia coli (ETEC) K88. Pigs, housed 4 per pen, were randomly allotted to 2 diets: 1) a high, 225 g/kg CP diet (HCP) or 2) a low, 176 g/kg CP diet (LCP) supplemented with crystalline amino acids. Pigs were orally challenged with 6 mL of an ETEC K88 suspension containing 1010 cfu/mL on d 8 after weaning. Blood samples were collected from 10 pigs (1 pig/pen) on d 7 (at weaning), −24 h, 8 h, 72 h and 7 d after the challenge for determination of plasma urea N (PUN) and serum concentrations of tumor necrosis factor alpha (TNF-α) and interleukin 1 beta (IL-1β) and haptoglobin (Hp). Tumor necrosis factor alpha, IL-1β and Hp were measured as indicators of inflammatory responses. The concentrations of serum TNF-α at 8 h, 72 h and 7 d after challenge were similar to the level observed at 24 h before challenge but higher (P < 0.05) than the weaning level. Pigs fed the LCP diet had lower (P = 0.032) concentrations of IL-1β (72 vs. 116 pg/mL) at 8 h post-challenge compared with those fed the HCP diet. Likewise, pigs fed the LCP diet tended to have lower (P = 0.088) concentration of Hp (9 vs. 25 mg/dL) compared with those fed the HCP diet at 8 h post-challenge. Compared with the weaning concentration, PUN concentration at 72 h after ETEC challenge was higher (P < 0.05) in pigs fed the HCP diet. The results indicate that the LCP diet supplemented with crystalline amino acids reduced inflammatory responses, as indicated by serum IL-1β, in piglets infected with ETEC K88. 相似文献
964.
965.
966.
It is common knowledge that fish are a nutritious component of a human diet, as they constitute a valuable and desired source of protein and polyunsaturated fatty acids. However, they are likely to pose a risk to consumer health. The presence of pathogenic bacteria or their toxins, parasites, biogenic amines and toxins or chemical residues may be a causal agent of foodborne illnesses in humans, sometimes even with fatal effect. Usually, infections are a result of insufficient thermal treatment or consumption of raw fish dishes. There are also risk factors that cannot be eliminated by such treatments as cooking, salting or freezing. 相似文献
967.
Invited review: Role of livestock in human nutrition and health for poverty reduction in developing countries 总被引:3,自引:0,他引:3
Randolph TF Schelling E Grace D Nicholson CF Leroy JL Cole DC Demment MW Omore A Zinsstag J Ruel M 《Journal of animal science》2007,85(11):2788-2800
Livestock keeping is critical for many of the poor in the developing world, often contributing to multiple livelihood objectives and offering pathways out of poverty. Livestock keeping also affects an indispensable asset of the poor, their human capital, through its impact on their own nutrition and health. This paper outlines the linkages between livestock keeping and the physical well-being of the poor, and examines a number of commonly held beliefs that misrepresent livestock development issues related to these linkages. These beliefs limit the scope of intervention programs to promote livestock and limit their potential contribution to poverty reduction. Recognition of the complexity of the role livestock play in household decision-making and of the opportunities foregone due to these misconceptions can enhance the ability of livestock to contribute to human well-being in the developing world. 相似文献
968.
G. A. Polton M. J. Brearley L. M. Green T. J. Scase 《Veterinary and comparative oncology》2007,5(4):232-238
The objective of this study was to determine whether an association could be demonstrated between survival and the expression of the adhesion molecule E‐cadherin by the neoplastic cells in a group of dogs with anal sac gland carcinomas (ASGCs). Archived formalin‐fixed, paraffin wax‐embedded primary tumour specimens were obtained for 36 cases of canine ASGC with known clinical management and survival data. Immunohistochemical methods were used to evaluate E‐cadherin expression by the neoplastic cells and data were evaluated for an association between E‐cadherin expression and survival. On univariate analysis, the median survival time for cases with tumours expressing E‐cadherin in more than 75% of cells was significantly greater than that for cases with tumours expressing E‐cadherin in fewer than 75% of cells (1168 versus 448 days, P = 0.0246). Both E‐cadherin expression and presence or absence of distant metastases were significantly associated with survival on multivariate analysis. This study demonstrates that expression of E‐cadherin at the cytoplasmic membrane in canine ASGCs is variable and potentially predictive of survival. 相似文献
969.
970.
Méndez-Angulo JL Swaab ME Malone E Olson EJ Chalkley MD Aird B Ward C 《The Canadian veterinary journal. La revue veterinaire canadienne》2011,52(12):1303-1307
A 12-year-old Quarter horse gelding was presented for evaluation of severe right forelimb lameness, 2 draining tracts over the lateral aspect of the right proximal antebrachium, and weight loss. A presumptive diagnosis of blastomycotic osteomyelitis was established based on radiographs and cytology of the exudate. This diagnosis was confirmed at necropsy. 相似文献