庆阳市3个肉牛养殖场青贮玉米品质评价

Quality evaluation of silage corn in three beef cattle farms in Qingyang City

摘要:

【目的】 研究和评价庆阳市肉牛养殖场全株青贮玉米营养品质及其安全性，为该地区青贮玉米的有效贮存和合理利用提供参考。【方法】 采集庆阳地区3 个肉牛养殖场A、B 及C 各青贮容器中表层、正常层、腐败发酵及暴露在空气中的发霉样品进行感官评定并测定其营养品质、发酵品质及霉菌毒素含量。【结果】 3 个肉牛养殖场青贮容器中正常层青贮样品的感官评分均为优，养殖场A 和B 表层青贮样品为良，而养殖场B 裹包青贮品质为中，养殖场C 二次发酵则为腐败。养殖场A 正常层样品的淀粉（Starch）含量较表层青贮样高32. 55%，而中性洗涤纤维（NDF）、酸性洗涤纤维（ADF）、pH 值、氨态氮（NH3-N）及乙酸（AA）含量则分别较表层（AS）低19. 95%、25. 13%、15. 61%、28. 69% 和38. 89%。养殖场B 裹包青贮中正常层样干物质（DM）、NDF、ADF 及NH3 ‐N 含量比裹包腐败发酵样品分别高0. 78%、21. 15%、31. 19% 和12. 55%，而Starch、粗灰分（Ash）及乳酸（LA）含量则分别低17. 44%、2. 71% 和10. 25%。养殖场C 正常层青贮样中Starch、NH3 ‐N、LA 和AA 含量较二次发酵饲草分别高32. 79%、30. 91%、66. 43% 和222. 37%，DM、粗蛋白（CP）、Ash 含量、pH 值较发霉样分别低0. 84%、47. 64%、64. 53% 和30. 91%。毒素检测结果表明，不同养殖场青贮饲料中黄曲霉毒素B1 和玉米赤霉烯酮含量均在正常范围内，而养殖场A 和B 表层样及养殖场B 裹包腐败发酵样中呕吐毒素超出正常范围。【结论】 庆阳3 个肉牛养殖场自制的全株青贮玉米品质差异较大，且各青贮容器中表层及二次发酵霉变青贮样品中呕吐毒素超标。

Abstract:

【Objective】 The experiment aims to evaluate the nutritional quality and safety of silage corn in threebeef cattle farms in Qingyang，so as to provide references for effective storage and rational utilization of silage corn inthis region.【Method】 Samples of surface layer （S），normal layer （N），spoilage fermentation （SF） and moldy （M）exposed to air in silage containers of A，B and C beef cattle farms of different scales in Qingyang were collected forsensory evaluation，nutritional fermentation quality and mycotoxin content analysis.【Result】 The sensory scores of silagein normal layer from three farms were all excellent，and silage samples in surface layers from farms A and B weregood，while it was evaluated as medium for the spoilage fermentation samples from farms B，and showed spoilage formoldy samples because of the second fermentation from farms C. Starch content in normal layer from farm A was32. 55% higher than that in surface layer，while the contents of NDF，ADF，pH value，ammonia nitrogen （NH3 ‐N）and acetic acid （AA） were 19. 95%，25. 13%，15. 61%，28. 69% and 38. 89% lower than those in surface layer（AS），respectively. The contents of DM，NDF，ADF and NH3‐N in normal layer of wrapped silage from farm B were0. 78%，21. 15%，31. 19% and 12. 55 % higher than those in wrapped spoilage samples，respectively. Starch，Ashand lactic acid（ LA） were 17. 44% and 2. 7% lower than those in the wrapped spoilage fermentation samples，respectively.The contents of starch，NH3 ‐N，LA and AA in normal layer from farm C were 32. 79%，30. 91%，66. 43%and 222. 37% higher than those of moldy silage，respectively. The DM，CP，Ash and pH were 0. 84%，47. 64%，64. 53% and 30. 91% lower than those of moldy silage，respectively. The toxin detection results showed that aflatoxinB1 and zearalenone contents in different state samples of different farms were within the normal range，and thevomitoxin contents in surface silage samples of farms A and B and the spoilage fermentation silage samples of farmsB were beyond the normal range.【Conclusion】 Overall，the quality of silage corn from three beef cattle farms in Qingyangarea was quite different，and the vomiting toxin in the surface samples and moldy silage samples in each silagecontainer exceeded the standard level.