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31.
Tropical Animal Health and Production - Currently for the reduction of methane (CH4) emissions are using fodder rich in condensed tannins, however, not yet known exactly how they act in the rumen...  相似文献   
32.
目前,规模化养猪场一般采取28-35日龄的仔猪早期断奶,在很大程度上提高了母猪的生产力及饲料的利用率,提高了猪场的经济,但随着仔猪断奶日龄的提高,也出现了许多生产上的问题,其中较为普遍而且影响较为严重的就是仔猪断奶后的转群应激。 在生产实践中,我们已克服了仔猪断奶应激,通过半年多的反复对比试验发现,在断奶仔猪转群后的3d-5d天内,饲料中添加一定量的电解多维,对缓解断奶仔猪因转群造成的食欲不振、消化不良、腹泻、膘情下降、抗病力减弱等不良反应均能起到满意的效果。1材料与方法1.1电解多维山东省明发…  相似文献   
33.
Virulent systemic feline calicivirus (VS-FCV) is a novel, emerging pathogen with mortality up to 67% even in previously healthy adult cats; VS-FCV has resulted in at least six epidemics since 1998. Affected cats have systemic vascular compromise and hemorrhagic-fever like signs in part due to viral invasion of epithelium and endothelium, coupled with host cytokine responses. Affected skin tissues had, on average, 3.8 elevated cytokines compared with control tissue, with prominent upregulation in IL-10, TNF-alpha, and MIP-1alpha. Sequencing of most of the genomes of two VS-FCV strains documented patterns of virus relatedness and implicated changes in the capsid gene in the emerging phenotype, possibly through initiation of immune mechanisms manifest in the cytokine changes. Understanding the features contributing to the emergence of this disease is critical for management and prevention of this and similar outbreaks attributable to RNA viruses in animals and humans.  相似文献   
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Blood coagulation is a basic physiological defense mechanism that occurs in all vertebrates to prevent blood loss following vascular injury. In all species the basic mechanism of clot formation is similar; when endothelium is damaged a complex sequence of enzymatic reactions occurs that is localized to the site of trauma and involves both activated cells and plasma proteins. The reaction sequence is initiated by the expression of tissue factor on the surface of activated cells and results in the generation of thrombin, the most important enzyme in blood clot formation. Thrombin converts soluble fibrinogen, via soluble fibrin monomers, into the insoluble fibrin that forms the matrix of a blood clot as well as exerting positive-feedback regulation that effectively promotes additional thrombin generation that facilitates the rapid development of a thrombus. Both spontaneous and trauma-induced haemorrhagic episodes can develop in all mammals with inherited or acquired abnormalities in one or more of the coagulant proteins. Experimental studies with plasma from a wide range of species have led to the conclusion that there are extensive differences in the rates of thrombin generation and fibrin formation among species. However, current evidence suggests that at least some of these quantitative differences are likely due to the use of non-species specific laboratory reagents. Although the individual proteins involved in the procoagulant pathways exhibit similar functions in all animals, differences in amino acid sequence cause incomplete homology and varying degrees of immunological cross-reactivity for the same protein across species.  相似文献   
36.
The aims of this study were to verify the efficacy of delayed hormonal treatments performed on day 25 post‐insemination on pregnancy rate at 45 and 70 days in buffalo. The trial was performed on 385 buffaloes synchronized by the Ovsynch/TAI protocol and submitted to artificial insemination (AI). Twenty‐five days after AI, pregnant animals were assigned to four treatments: (1) GnRH agonist (n = 52), 12 μg of buserelin acetate; (2) hCG (n = 51), 1500 IU of human chorionic gonadotrophin; (3) Progesterone (n = 47), 341 mg of P4 intramuscular (im) every 4 days for three times; (4) Control (n = 54), treatment with physiological saline (0.9% NaCl). Milk samples were collected on days 10, 20 and 25 after AI in all buffaloes to determine progesterone concentration in whey by radioimmunoassay method. Statistical analysis was performed by anova . Pregnancy rate on day 25 after AI was 52.9%, but declined to 41.8% by day 45, indicating an embryonic mortality (EM) of 21%. If only control group is considered, the incidence of EM was 38.9%. Pregnant buffaloes had higher (p < 0.01) progesterone concentrations on day 20 and 25 after AI than both non‐pregnant buffaloes and buffaloes that showed EM. The treatments on day 25 increased (p < 0.01) pregnancy rate, although in buffaloes with a low whey progesterone concentration on day 20 and 25 after AI (n = 22); all treatments were ineffective to reduce EM.  相似文献   
37.
Feline immunodeficiency virus sustains an AIDS-like syndrome in cats, which is considered a relevant model for human AIDS. Under precise enrolment requirements, 30 naturally infected cats showing overt disease were included in a trial of low-dose, oral human interferon-alpha treatment. Twenty-four of them received 10 IU/Kg of human interferon-alpha and 6 placebo only on a daily basis under veterinary supervision. The low-dose human interferon-alpha treatment significantly prolonged the survival of virus-infected cats (p<0.01) and brought to a rapid improvement of disease conditions in the infected hosts. Amelioration of clinical conditions was neither correlated with plasma viremia, nor with proviral load in leukocytes. A good survival of CD4+ T cells and a slow increase of CD8+ T cells were also observed in human interferon-alpha-treated cats. Interestingly, the improvement of the total leukocyte counts showed a much stronger correlation with the recovery from serious opportunistic infections. As shown in other models of low-dose interferon-alpha treatment, there was a rapid regression of overt immunopathological conditions in virus-infected cats. This hints at a major role of interferon-alpha in the control circuits of inflammatory cytokines, which was probably the very foundation of the improved clinical score and survival despite the unabated persistence of virus and virus-infected cells.  相似文献   
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The genomic region spanning the two ribosomal RNA internal transcribed spacers (ITS1 and ITS2) and the 5.8S rRNA gene was cloned and sequenced from sixteen Theileria isolates. Each Theileria species possessed ITS1 and ITS2 of unique size(s) and species specific nucleotide sequences. Varying degrees of ITS1 and ITS2 intra- and inter-species sequence polymorphism were found among ruminant Theileria species. The spacers were most polymorphic in the agent of tropical theileriosis, Theileria annulata, and were more conserved in two benign species, Theileria buffeli and Theileria sergenti Chitose. Phylogenetic analysis of the rDNA ITS1-5.8S rRNA gene-ITS2 region clearly separated each taxon, placing them in three clusters. One held T. annulata, Theileria parva, and Theileria mutans, with the latter two most closely related. The second held T. sergenti Ikeda, T. sergenti Chitose, and T. buffeli, with the latter two most closely related. The third cluster held the Theileria ovis isolates.  相似文献   
40.
Five horses were examined because of signs of muscle stiffness, colic, or both. All 5 had been exposed to Streptococcus equi within 3 weeks prior to examination or had high serum titers of antibodies against the M protein of S equi. Horses had signs of unrelenting colic-like pain and focal areas of muscle swelling. Four horses were euthanatized. The fifth responded to treatment with penicillin and dexamethasone; after 3 weeks of treatment with dexamethasone, prednisolone was administered for an additional 10 weeks. Common hematologic and serum biochemical abnormalities included neutrophilia with a left shift and toxic changes, hyperproteinemia, hypoalbuminemia, and high serum creatine kinase and aspartate transferase activities. Necropsy revealed extensive infarction of the skeletal musculature, skin, gastrointestinal tract, pancreas, and lungs. Histologic lesions included leukocytoclastic vasculitis in numerous tissues and acute coagulative necrosis resembling infarction. These horses appeared to have a severe form of purpura hemorrhagica resembling Henoch-Sch?nlein purpura in humans and characterized by infarction of skeletal muscles. Early recognition of focal muscle swelling, abdominal discomfort, neutrophilia, hypoalbuminemia, and high serum creatine kinase activity combined with antimicrobial and corticosteroid treatment may enhance the likelihood of a successful outcome.  相似文献   
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