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Nutraceuticals have gained immense importance in poultry science recently considering the nutritional and beneficial health effects of their constituents. Besides providing nutritional requirements to birds, nutraceuticals have beneficial pharmacological effects, for example, they help in establishing normal physiological health status, prevent diseases and thereby improve production performance. Nutraceuticals include amino acids, vitamins, minerals, enzymes, etc. which are important for preventing oxidative stress, regulating the immune response and maintaining normal physiological, biochemical and homeostatic mechanisms. Nutraceuticals help in supplying nutrients in balanced amounts for supporting the optimal growth performance in modern poultry flocks, and as a dietary supplement can reduce the use of antibiotics. The application of antibiotic growth enhancers in poultry leads to the propagation of antibiotic-resistant microbes and drug residues; therefore, they have been restricted in many countries. Thus, there is a demand for natural feed additives that lead to the same growth enhancement without affecting the health. Nutraceuticals substances have an essential role in the development of the animals’ normal physiological functions and in protecting them against infectious diseases. In this review, the uses of amino acids, vitamins and minerals as well as their mode of action in growth promotion and elevation of immune system are discussed.  相似文献   
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A single-tube, non-interrupted, one-step RT-PCR has been standardized to amplify the hypervariable region of the VP2 gene sequence of infectious bursal disease virus (IBDV). The technique standardized on purified viral RNA was successfully applied to the detection of the virus directly in clinical samples. The amplified products were confirmed to be IBDV specific by their size in ethidium bromide-stained agarose gel, nested PCR and restriction enzyme digestion. Digestion of the amplicons with StyI restriction enzyme also differentiated classical virus from six very virulent field isolates. The sensitivity of the one-step RT-PCR was found to be 0.2 pg of viral RNA.  相似文献   
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Evaluation of hyperimmune sera against goat pox viral antigens   总被引:1,自引:0,他引:1  
Tropical Animal Health and Production -  相似文献   
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The objective of this study was to explore the possibility of producing wild buffalo embryos by interspecies somatic cell nuclear transfer (iSCNT) through handmade cloning using wild buffalo somatic cells and domestic buffalo (Bubalus bubalis) oocytes. Somatic cells derived from the ear skin of wild buffalo were found to express vimentin but not keratin and cytokeratin‐18, indicating that they were of fibroblast origin. The population doubling time of skin fibroblasts from wild buffalo was significantly (p < 0.05) higher, and the cell proliferation rate was significantly (p < 0.05) lower compared with that of skin fibroblasts from domestic buffalo. Neither the cleavage (92.6 ± 2.0% vs 92.8 ± 2.0%) nor the blastocyst rate (42.4 ± 2.4% vs 38.7 ± 2.8%) was significantly different between the intraspecies cloned embryos produced using skin fibroblasts from domestic buffalo and interspecies cloned embryos produced using skin fibroblasts from wild buffalo. However, the total cell number (TCN) was significantly (p < 0.05) lower (192.0 ± 25.6 vs 345.7 ± 42.2), and the apoptotic index was significantly (p < 0.05) higher (15.1 ± 3.1 vs 8.0 ± 1.4) for interspecies than that for intraspecies cloned embryos. Following vitrification in open‐pulled straws (OPS) and warming, although the cryosurvival rate of both types of cloned embryos, as indicated by their re‐expansion rate, was not significantly different (34.8 ± 1.5% vs 47.8 ± 7.8), the apoptotic index was significantly (p < 0.05) higher for vitrified–warmed interspecies than that for corresponding intraspecies cloned embryos (48.9 ± 7.2 vs 23.9 ± 2.8). The global level of H3K18ac was significantly (p < 0.05) lower in interspecies cloned embryos than that in intraspecies cloned embryos. The expression level of HDAC1, DNMT3a and CASPASE3 was significantly (p < 0.05) higher, that of P53 was significantly (p < 0.05) lower in interspecies than in intraspecies embryos, whereas that of DNMT1 was similar between the two types of embryos. In conclusion, these results demonstrate that wild buffalo embryos can be produced by iSCNT.  相似文献   
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Immunization against Angara disease virus (ADV), a serotype 4 avian adenovirus, and Newcastle disease virus (NDV), an avian paramyxovirus serotype 1, is the mainstay of a broiler vaccination programme, while polyether ionophores usually form an essential component of a broiler medication programme in most parts of India and Pakistan. The role of polyether ionophores in the protective immune responses of broiler chickens vaccinated and challenged with ADV and NDV was investigated. A total of 1600 birds were divided into eight groups of 200 birds each. First four groups were vaccinated against NDV and ADV, while the remaining four served as unvaccinated controls. The first 3 groups of birds were administered salinomycin, monensin and cyclophosphamide (CYP), respectively. The last group served as an untreated control. The same treatment schedule was also followed for the next four unvaccinated groups. The post-vaccination and post-challenge serological responses to NDV and ADV, body and lymphoid organ weight gains, post-challenge survival rate and detection of NDV and ADV in the tissues of infected birds were evaluated. Birds administered salinomycin showed a significant stimulation of protective immune responses against both NDV and ADV as compared to the untreated and CYP-treated birds. Monensin also enhanced the protective immune responses against both viruses but the effect was not statistically significant. Thus, it is concluded that monensin and salinomycin augment the anti-NDV and anti-ADV immune responses in broiler chickens, which supports their use in poultry flocks.  相似文献   
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