饲喂不同种类粗饲料的辽宁绒山羊瘤胃内酸碱环境及氮代谢的研究

Reach on Rumen parameters of acid and nitrogen metabolizing of Liaoning Cashmere Goat Fed with different Sorts of Roughages

本试验选择9只年龄3.2±0.2岁、体重50.4±2.6kg的装有永久性瘤胃瘘管的成年辽宁绒山羊公羊为试验动物。采用随机区组设计,将动物分为3组,分别饲喂给以玉米秸、大豆秸、花生秸为主的1、2、3号试验日粮,每天8:00和16:00饲喂,全天自由饮水。试验预试期15d,试验期15d,连续7d测排尿量,采集瘤胃液、尿液,研究瘤胃内酸度和氮代谢参数。结果表明:三组的瘤胃液pH、乳酸浓度、总酸度、TVFA和戊酸均差异不显著(P>0.05)。从试验1组到3组,瘤胃液TVFA浓度、乙酸浓度、丙酸浓度、异丁酸浓度、丁酸浓度、异戊酸浓度均呈增加趋势;其中试验3组的丙酸和异丁酸、异戊酸均显著(P<0.05)高于1组;并且试验3组的丁酸极显著(P<0.01)高于1组;其他的差异不显著(P>0.05)。试验1组瘤胃NH4-N极显著(P<0.01)低于试验2组和试验3组,而后两组差异不显著(P>0.05);试验1组UN浓度显著(P<0.05)低于试验3组,但与试验2组差异不显著(P>0.05);三个试验组瘤胃液BCP浓度和MCP合成量均差异不显著(P>0.05),但试验2组与3组BCP浓度和MCP合成量均高于试验1组。相关分析表明,瘤胃MCP(y,g/d)合成量与瘤胃液TVFA(x,mmol/L)浓度存在显著相关关系:y=2.32x+2.22,r2=0.61,P<0.05;瘤胃MCP(y,g/d)合成量与瘤胃液丙酸浓度(x,mmol/L)存在显著相关关系:y=0.23x+9.68,r2=0.64,P<0.05;瘤胃液MCP(y,g/d)与UN(x,mg/L)存在显著的线性关系:y=1.32x+2.53,r2=0.78,P<0.05。因此,以花生秸为主的日粮瘤胃液BCP浓度、MCP合成量较高,秸秆粗饲料转化利用效率较好,提高该日粮的能量蛋白水平会进一步增加微生物蛋白的合成和动物对其的利用。

Nine Liaoning Cashmere Goats （3.2±0 2 years old, body weight=23.11±1.03 kg） were randomly divided into three groups to investigate rumen parameters of acid and nitrogen metabolizing fed with three ra- tions made mainly of corn stalk, soybean stalk and peanut stalk respectively. All the rams were fed at 8：00 and 16：00, and ad libitum drink. The results showed there were no significant diffrence among the three groups in the value of rumen pH, lactic acid, TVFA and valeric acid though TVFA, acetic acid, acetone acid, buty acid and ~aleric acid were increasing from group I to Ill .There were extremityly significant diffrence{P〈O.01 } be- tweeen group I and U ,.group I and m in rumen NH4-NNH4-N; There was significant diffrence{P〈0.05} betweeen group I and ]1I in tureen UN; there were no significant diffrence（P 〈 0.05） among all the groups in ru- men BCP and MCP although the values increasing from group Ⅰ to Ⅲ. And the relationship between rumen MCP（y, g/d） arid TVFA （μ mmol/L） was： y = 2.32x ＋ 2.22, r2 = 0.61, P〈 0.05; the relationship between rumen MCP（y,g/d） and acetone acid{x,mmol/L} was：y= 0.23x ＋ 9.68, r2 = 0.64, P〈0.05;the relationship between ru- men MCP（y,g/d） and UN {x,mg/L） was： y = 1.32x ＋ 2.53, r2= 0.78, P〈0.05. In conclusion the rumen mierobse produce more MCP in rumen fed with ration made mainly of peanut stalk than others, and the utilization efficiency of feed was the higest.