宰前因素调节对牛肉肉质的改善作用

发布时间：2018-05-04 17:46

本文选题：肉牛 + 季节　；参考：《吉林农业大学》2015年硕士论文

【摘要】：随着我国经济的发展,居民生活水平不断提高,居民食品消费结构也在不断完善,牛肉市场也在逐年扩大。但是由于宰前阶段应激反应会导致牛肉的品质下降,国内对肉牛应激反应解决方式的研究还不够完善,本论文分为三部分,分别研究:不同季节不同室温条件宰前肉牛体温和宰后肌糖原含量与排酸后牛肉pH的关系(试验一),分别在冬季(室温6℃),春季(室温19℃),夏季(室温27℃)采集肉牛的体温、pH值、肌糖原含量数据,研究季节(室温)、pH值、肌糖原含量三者之间的关系,同时,宰前15天使用不同能量水平的日粮饲喂肉牛,研究日粮能量水平与排酸后牛肉pH之间的关系(试验二),并尝试通过宰前补饲能量物质和特殊营养物质(葡萄糖、肌醇、褪黑激素)改善牛肉宰前应激和牛肉肉质(试验三)。试验一:对不同季节不同室温条件下宰前肉牛体温、宰后肌糖原含量与排酸后牛肉pH值之间的关系进行了系统研究。结果表明,肌糖原含量与排酸后牛肉pH值之间呈负相关,肌糖原含量越高,宰后pH值越低,说明确实存在过量消耗肌糖原导致排酸期间底物不足,产生乳酸量减少致使pH值无法降低的情况。同时不同季节不同温度也对糖原含量和排酸后牛肉pH值有显著影响,随着气温升高,肉牛平均糖原含量与pH值也显著升高,至夏季达到高峰,同时高pH值肉牛的发生几率也显著提高,表明温度确实会加剧肉牛的宰前应激,导致宰前肉牛体内肌糖原被过量消耗,排酸期间乳酸产生含量减少,最终牛肉的极限pH值更高。试验二:研究了宰前肉牛不同日粮能量水平对牛肉排酸后pH值和屠宰率的影响。结果表明,无氮浸出物摄入量对牛肉排酸后pH值有显著影响,呈负相关,无氮浸出物摄入量高的肉牛试验组排酸后的最终极限pH值显著低于无氮浸出物摄入量低的试验组,说明能量水平的高低对肉牛整体能量代谢有影响,能量水平高的肉牛会在体内储存更多的糖原和脂肪,经宰前应激阶段消耗后剩余的糖原含量也更多,经排酸后pH值也会下降到更低的水平;粗蛋白摄入量对肉牛的屠宰率影响显著,呈正相关,粗蛋白摄入量高的肉牛试验组屠宰率显著高于粗蛋白摄入量低的试验组,表明粗蛋白对肉牛增重的影响最大,影响体内蛋白质代谢,增加蛋白沉积转化为肌肉组织。试验三:分析对待宰阶段肉牛补饲葡萄糖、肌醇和褪黑激素对排酸后牛肉pH值、屠宰率的影响。结果表明,宰前24h内补饲葡萄糖对排酸后牛肉pH值、屠宰率影响显著,说明由于宰前断食,肉牛体内能量消耗没有补充,经葡萄糖补充后,补充能量,对宰前应激有正面影响,由于经过能量补充,体内糖原含量增加,应激对糖原消耗量不变的情况下至屠宰时肌肉中肌糖原存量也增加,最终排酸后牛肉的pH值更低;宰前24h内补饲肌醇对排酸后牛肉pH值影响显著,对屠宰率影响不显著,说明宰前补饲的肌醇较好的发挥了补充能量的效果,也减少了肌糖原的消耗,但对屠宰率影响不显著,说明短期内补充少量肌醇对肉牛体重增加影响不大;宰前24h内补饲褪黑激素对排酸后牛肉pH值、屠宰率影响不大,没有相关性,表明短期内补充褪黑激素对增加肉牛睡眠时间,减少应激反应并无影响,也不能影响肉牛增重。
[Abstract]:With the development of China's economy, the living standard of residents is constantly improving, the structure of food consumption is being perfected, and the beef market is expanding year by year. However, the stress reaction in the pre slaughter stage will lead to the decline of beef quality, and the research on the coping style of beef stress reaction in China is not perfect. This paper is divided into three parts, respectively. The relationship between the body temperature of beef cattle before slaughter in different seasons and the content of the muscle glycogen after slaughter and the pH of beef after the slaughter (test one) were collected in winter (Shi Wen 6 C), spring (Shi Wen 19), and summer (Shi Wen 27) to collect body temperature, pH value, muscle glycogen content, study season (Shi Wen), pH value, and muscle glycogen content three. At the same time, 15 days before slaughter, beef cattle were fed with diets with different energy levels, and the relationship between dietary energy level and beef pH after acid removal was studied (test two), and the pre slaughter of energy material and special nutrients (glucose, inositol, melatonin) Gai Shanniu meat before slaughter stress and beef meat quality (test three). The relationship between the body temperature of beef cattle before slaughter under different room temperature, the relationship between the content of the postmortem muscle glycogen and the pH value of the beef after the acid removal was systematically studied. The results showed that the content of muscle glycogen was negatively correlated with the pH value of beef after acid discharge, the higher the content of the muscle glycogen and the lower the pH value after the slaughter, it was proved that the excess consumption of muscle glycogen led to the substrate during the acid discharge. At the same time, the average glycogen content and the pH value of beef were significantly affected by the different temperatures in different seasons. The average glycogen content and pH value of beef cattle increased significantly with the increase of temperature, and reached the peak in summer and the incidence of high pH beef cattle increased significantly, Biao Mingwen. Biao Mingwen Degrees do aggravate the pre slaughter stress of beef cattle, resulting in excessive consumption of muscle glycogen in the body of beef cattle before slaughter, the decrease in lactic acid production during acid discharge and the higher pH value of the final beef. Experiment two: the effects of different dietary energy levels on the pH value and slaughter rate of beef after slaughtering were studied. The pH value of beef was negatively correlated, and the ultimate pH value of the beef cattle test group with high intake of nitrogen free extract was significantly lower than the low intake of nitrogen free extract, indicating that the energy level had an impact on the overall energy metabolism of beef cattle, and the high energy level beef cattle could store more glycogen in the body. Fat, after the consumption of pre slaughter stress, the remaining glycogen content was also more, and the pH value decreased to a lower level after acid removal. The crude protein intake had a significant effect on the slaughter rate of beef cattle, which was positively correlated. The slaughter rate in the beef cattle test group with high crude protein intake was significantly higher than the low protein intake test group, indicating that crude protein was used for beef cattle. The effect of weight gain was the greatest, affecting protein metabolism in the body and increasing protein deposition into muscle tissue. Experiment three: the effects of supplementing glucose, inositol and melatonin on pH value and slaughter rate of beef after slaughtering were analyzed. The results showed that the effect of supplementing glucose in 24h on the pH value and slaughter rate of beef after slaughtering was significant. The energy consumption of beef cattle was not supplemented before slaughter. After supplementation of glucose, it had a positive effect on pre slaughter stress. As a result of energy supplement, the content of glycogen in the body increased, and the muscle sugar in the muscle increased in the condition of the constant consumption of glycogen to slaughter, and the pH value of beef was lower. The effect of inositol in pre 24h on beef pH value after acid removal was significant, and the effect on slaughter rate was not significant. It indicated that inositol supplementation before slaughter played a good role in supplementing energy and reduced the consumption of muscle glycogen, but the effect on slaughter rate was not significant. It indicated that a small amount of myosol supplementation in the short term had little effect on the weight gain of beef cattle; 24h supplementation before slaughter was used. Melatonin had little influence on the pH value and slaughter rate of beef after acid removal. It showed no correlation, indicating that the short-term supplementation of melatonin had no effect on increasing the sleep time of beef cattle and reducing stress response, and could not affect beef weight gain.

【学位授予单位】：吉林农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S823

【相似文献】