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微贮牧草对山羊生产性能、饲粮养分消化率和消化道微生物数量的影响 总被引:1,自引:0,他引:1
试验使用黑曲霉、乳酸菌、酵母菌3种微生物的固体菌剂以及尿素作为微生态制剂青贮(微贮)高丹草和牛鞭草,并对64只黑山羊进行30 d饲养对比试验,研究高丹草和牛鞭草青贮对山羊生产性能、饲粮养分消化率和消化道微生物数量的影响。试验结果为,相比于普通青贮(普贮),微贮高丹草酵母菌、黑曲霉、乳酸菌数量分别增加了475.61%、290.65%和513.37%;微贮牛鞭草酵母菌、黑曲霉、乳酸菌数量分别增加了466.67%、762.07%和486.05%;微贮组羊瘤胃中的酵母菌、黑曲霉和乳酸菌数量均极显著增加(P0.01);微贮组羊粪中的酵母菌、黑曲霉和乳酸菌数量显著或极显著增加(P0.05),大肠杆菌数量极显著降低(P0.001);微贮组饲粮除中性洗涤纤维的表观消化率极显著高于普贮组(P0.01),其余均显著高于普贮组(P0.05);微贮组平均日增重和饲料转化率显著高于普贮组(P0.05)。综上所述,微生态制剂青贮不仅可增加瘤胃和粪中酵母菌、黑曲霉和乳酸菌数量,减少粪中大肠杆菌的数量,还能提高山羊饲粮表观消化率和生长性能。 相似文献
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Zhi-qiang Li Dan Gui Zhi-hua Sun Jun-bo Zhang Wen-zhi Zhang Hui Zhang Fei Guo Chuang-fu Chen 《Journal of veterinary science (Suw?n-si, Korea)》2015,16(4):467-473
Brucellosis is a zoonotic disease that causes animal and human diseases. Vaccination is a major measure for prevention of brucellosis, but it is currently not possible to distinguish vaccinated animals from those that have been naturally infected. Therefore, in this study, we constructed the Brucella (B.) abortus 2380 wbkA mutant (2308ΔwbkA) and evaluated its virulence. The survival of 2308ΔwbkA was attenuated in murine macrophage (RAW 264.7) and BALB/c mice, and it induced high protective immunity in mice. The wbkA mutant elicited an anti-Brucella-specific immunoglobulin G response and induced the secretion of gamma interferon. Antibodies to 2308ΔwbkA could be detected in sera from mice, implying the potential for use of this protein as a diagnostic antigen. The WbkA antigen would allow serological differentiation between infected and vaccinated animals. These results suggest that 2308ΔwbkA is a potential attenuated vaccine against 16M. This vaccine will be further evaluated in sheep. 相似文献
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The effects of replacement of whole‐plant corn with oat and common vetch on the fermentation quality,chemical composition and aerobic stability of total mixed ration silage in Tibet 下载免费PDF全文
Lei Chen Gang Guo Chengqun Yu Jie Zhang Masataka Shimojo Tao Shao 《Animal Science Journal》2015,86(1):69-76
The objective of this experiment was to evaluate the effects of replacement of whole‐plant corn with oat and common vetch on the fermentation quality, chemical composition and aerobic stability of total mixed ration (TMR) silage in Tibet. Four TMR that varied in the forage sources on dry matter basis were used: (i) 52% whole‐plant corn (Control); (ii) 43% oat + 12% common vetch (OC3.6); (iii) 38% oat + 18% common vetch (OC2.2); and (iv) 33% oat + 23% common vetch (OC1.5). Silos were opened on day 45 and then subjected to an aerobic stability test for 12 days. The results showed that all silages were well preserved with low pH and NH3‐N, and high lactic acid and V‐scores. With the increasing proportion of common vetch, crude protein, ether extract increased (P < 0.05), and neutral detergent fiber and acid detergent fiber decreased (P < 0.05). Under aerobic conditions, treated silages were more stable than the control silage as indicated by lower (P < 0.05) pH and yeast population. It was concluded that replacement of whole‐plant corn with oat and common vetch had no unfavorable effects on the fermentation quality and improved crude protein content and aerobic stability of TMR silage. OC2.2 silage was the best among three treated TMR silages. 相似文献
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