静养时间对肉牛运输应激消除作用的影响研究

发布时间：2018-06-13 09:45

本文选题：长途运输应激 + 宰前静养　；参考：《河北农业大学》2015年硕士论文

【摘要】：随着我国肉牛生产发展迅猛,集中运输屠宰的肉牛数量日益增多,运输应激成为我国肉牛生产中不可避免的重要应激因素之一。运输应激容易造成肉牛损伤及生理机能下降,影响动物的生产性能和肉品质下降。宰前静养是缓解肉牛长途应激的主要途径,在一定程度上可以缓解肉牛的运输应激,提高肉牛生产性能和肉品质。经过调研发现目前国内企业主要采用0-24h以内的静养,静养效果并不理想,造成肉牛体重持续下降,肉品质降低。本试验首先对我国部分省市的肉牛屠宰企业进行调查,总结宰前管理现状;并就大于24h的静养对肉牛的影响进行了研究,旨在为我国肉牛屠宰提供一定的理论参考。1.肉牛宰前管理调查我国长途运输肉牛所占比重较大;经过长途运输后肉牛活重下降明显,屠宰率和净肉率有降低的趋势,造成经济损失;大部分企业忽视宰前静养,无静养直接屠宰或者静养时间太短,静养时间长短没有考虑运输距离,缺乏科学合理的运输应激消除技术。2.静养时间对肉牛生理生化及肌肉组织的影响研究为了研究静养对于消除长途运输应激对肉牛影响的效果,为肉牛企业实际生产选取合适的肉牛静养时间,试验选取体重相近(600kg±50kg)的西门塔尔公牛36头做屠宰测定,其中6头不进行运输,作为对照组。运输前编号,称重。经长途运输(600km以上)抵达屠宰场后称重,于0h、24h、72h、120h、168h分别屠宰各6头,宰时采血,用于测定生理生化指标,宰后排酸成熟72h后测定肉品质相关指标。试验结果表明,肉牛经过长途运输立即屠宰降低肉品品质;血液生理生化指标、p H值、滴水损失、蒸煮损失、剪切力等指标在72h至120h静养期间呈现恢复状态,与对照组最接近(具体结果见试验部分);在静养168h时,血液生理生化指标及肉品品质又表现出下降的趋势,可能产生了新的应激。长途运输肉牛宰前静养72~120h为宜。3.静养时间对长途运输肉牛生产性能的影响本试验研究了长途运输的肉牛在静养0h-168h过程中,活重损失率、出肉率、净肉率、经济效益的动态变化。试验选取体重相近(600kg±50kg)的西门塔尔公牛36头做屠宰测定,其中6头作为对照组,不进行长途运输。运输前编号,称重。经长途运输(600km以上)抵达屠宰场后,称重。于0h、24h、72h、120h、168h分别屠宰各6头,宰后称重分析。结果表明:肉牛静养过程中,活重损失率从静养0h到72h呈降低趋势,从静养72h到168h呈升高趋势;静养72h组净肉率显著大于其他试验组(P0.05);与对照组相比,静养0h组市场差值最大,静养72h组市场差值最小。说明静养72h活重损失率最低,净肉率、出肉率、经济核算均与对照组最接近。因此,经过长途运输肉牛建议静养72h后再进行屠宰。
[Abstract]:With the rapid development of beef cattle production in China, the number of beef cattle transported and slaughtered is increasing day by day. Transportation stress has become one of the unavoidable important stress factors in the production of beef cattle in China. Transport stress can easily cause injury and decline of physiological function of beef cattle, and affect the performance and meat quality of animals. Pre-mortem rest is the main way to alleviate the long-distance stress of beef cattle. To some extent, it can alleviate the transport stress of beef cattle and improve the production performance and meat quality of beef cattle. After investigation, it was found that the domestic enterprises mainly used 0-24 hours of rest, the effect of rest is not ideal, resulting in continuous loss of beef weight and meat quality. This experiment firstly investigated the butcher enterprises of beef cattle in some provinces and cities of our country, summarized the present situation of the management before slaughter, and studied the influence of the rest feeding for more than 24 hours on the beef cattle, in order to provide certain theoretical reference for the slaughter of beef cattle in our country. Investigation on Beef Beef Management before slaughter the proportion of beef cattle transported over long distances in our country is relatively large. After long-distance transportation, the live weight of beef cattle decreases significantly, and the slaughter rate and net meat rate decrease, which results in economic losses. Most enterprises neglect pre-mortem rest. Direct slaughter without rest or short rest time, the length of rest time does not take into account the transport distance, lack of scientific and reasonable transport stress elimination technology. 2. Study on the effects of resting time on physiological, biochemical and muscle tissue of Beef cattle in order to study the effect of resting time on the elimination of long-distance transport stress on beef cattle, the appropriate time for beef cattle production was selected. In the experiment, 36 Simmental bulls with similar body weight (600kg 卤50kg) were slaughtered and 6 of them were not transported as control group. Number before transportation, weighing. After arriving at the slaughterhouse, 6 heads were slaughtered at 0 h, 24 h, 72 h, 120 h and 168 h, respectively. Blood was collected at the time of slaughter, which was used to measure physiological and biochemical indexes, and meat quality was measured after 72 h of acid excretion after slaughter. The results showed that beef cattle were slaughtered immediately after long distance transportation to reduce meat quality, blood physiological and biochemical indexes such as pH value, drip loss, cooking loss, shear stress and so on showed a recovery state during 72 hours to 120 hours of rest. The results showed that the blood physiological and biochemical indexes and meat quality showed a downward trend after 168h of rest, which may lead to new stress. Long distance transportation of beef cattle before slaughter for 72U 120h is appropriate. 3. Effects of resting time on the production performance of Long-distance Transport Beef cattle the dynamic changes of live weight loss rate of meat yield net meat rate and economic benefit of long-distance transport beef cattle during 0h-168h were studied. In the experiment, 36 Simmental bulls with similar body weight (600kg 卤50kg) were slaughtered and 6 of them were used as control group without long-distance transportation. Number before transportation, weighing. After long-distance transportation above 600 km) arrived at the slaughterhouse, weighing. Six heads were slaughtered at 0 h, 24 h, 72 h, 120 h and 168 h, respectively. The results showed that the loss rate of live weight decreased from 0 h to 72 h, and increased from 72 h to 168 h, and the net meat rate of 72h group was significantly higher than that of other experimental groups, and the market difference between 0 h group and control group was the largest. The market difference was the smallest in 72 h rest group. The results showed that the loss rate of live weight in 72 hours was the lowest, the net meat rate, meat output rate and economic calculation were the most close to those of the control group. Therefore, after long-distance transport of beef cattle recommended 72 hours of rest before slaughter.
【学位授予单位】：河北农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S823

【参考文献】