作 者：
柏峻;赵二龙;李艳娇;李美发;辛均平;杨食堂;杨建军;易中华;瞿明仁;许兰娇
单 位：
国家肉牛产业技术体系高安试验站;江西农业大学江西省动物营养重点实验室饲料工程研究中心
摘 要：
本试验旨在探讨饲粮能量水平对育肥前期锦江牛屠宰性能、肉品质及血清内源激素含量的影响。试验选用50头初始体重为(301.7±30.1) kg的锦江去势公牛,随机分成5个组,即A、B、C、D和E组,每组10头,分为4个重复,每个重复2～3头牛。参照我国《肉牛饲养标准》配制基础饲粮,A组饲喂基础饲粮,B、C、D、E组饲粮的综合净能水平在基础饲粮的基础上依次提高6%、12%、18%、24%。5组饲粮的粗蛋白质水平保持一致,综合净能水平分别为6.02(A组)、6.38(B组)、6.74(C组)、7.10(D组)、7.46 MJ/kg(E组)。饲喂116 d后,禁饲12 h,每组选择3头体重接近于该组平均体重的牛进行屠宰,测定其屠宰性能及肉品质。结果显示:1)随着饲粮综合净能水平的提高,锦江牛背膘厚度呈先下降后上升的趋势,其中C组锦江牛背膘厚度最低(2.01 cm),而眼肌面积则逐渐增大,以E组锦江牛眼肌面积最高(81.04 cm~2)。2)随着饲粮综合净能水平的提高,背最长肌pH_(45)min逐渐下降,D、E组显著低于A组(P<0.05); C、D、E组背最长肌剪切力显著低于A、B组(P<0.05)。饲粮能量水平对背最长肌pH_(24h)、肉色(亮度、红度、黄度值)、滴水损失和蒸煮损失均无显著影响(P>0.05)。3) C组锦江牛背最长肌粗脂肪、粗蛋白质含量显著高于其余组(P<0.05),而背最长肌水分、粗灰分含量各组之间差异不显著(P>0.05)。4) E组血清生长激素含量显著高于A、B、C组(P <0. 05); C组血清瘦素含量显著低于A、B、D组(P<0.05),血清脂联素含量显著高于其余各组(P <0.05)。综上所述,在本试验条件下,结合屠宰性能、肉品质及血清内源激素含量等指标得出,C组饲粮的能量水平(综合净能水平为6.74 MJ/kg)比较适于育肥前期舍饲锦江黄牛生产优质牛肉所需的能量水平。
译 名：
Effects of Dietary Energy Level on Slaughter Performance, Meat Quality and Serum Endogenous Hormone Contents of Jinjiang Steers in Early Stage of Fattening
作 者：
BAI Jun;ZHAO Erlong;LI Yanjiao;LI Meifa;XIN Junping;YANG Shitang;YANG Jianjun;YI Zhonghua;QU Mingren;XU Lanjiao;Engineering Research Center of Feed Development,Jiangxi Province Key Laboratory of Animal Nutrition,Jiangxi Agricultural University;National Beef Cattle Industrial Technology System of G aoan Test Station;
单 位：
BAI Jun%ZHAO Erlong%LI Yanjiao%LI Meifa%XIN Junping%YANG Shitang%YANG Jianjun%YI Zhonghua%QU Mingren%XU Lanjiao%Engineering Research Center of Feed Development,Jiangxi Province Key Laboratory of Animal Nutrition,Jiangxi Agricultural University%National Beef Cattle Industrial Technology System of G aoan Test Station
关键词：
Jinjiang steers;;energy level;;slaughtering performance;;meat quality
摘 要：
This experiment was conducted to explore the effects of diet energy level on the slaughtering performance,meat quality and serum endogenous hormone contents of Jinjiang steers in early stage of fattening.Fifty Jinjiang steers with good body condition and similar body weight of (301.7±30.1) kg were randomly divided into 5 groups (groups A,B,C,D and E) with 10 heads in each group,and each group had 4 replicates with 2 to 3 steers per replicate. A basal diet was prepared by reference to China Beef Cattle Feeding Standard.Group A was fed the basal diet,and the combined net energy (NE_(mf)) levels of steers in groups B,C,D and E were increased by 6%,12%,18% and 24%,respectively,on the basis of the basal diet. The crude protein level of the 5 diets was consistent,and the NE_(mf) level of the 5 diets was 6.02 (group A),6.38 (group B),6.74 (group C),7.10 (group D) and 7.46 M J/kg (group E),respectively. After 116 days of feeding,the animals were forbidden to be fed for 12 h. For each group,three cows with body weight close to the average weight of that group were selected for slaughter to determine their slaughtering performance and meat quality.The results showed as follows: 1) with the increase of the dietary NE_(mf)level,the backfat thickness of Jinjiang steers showed a trend of first decreasing and then rising,among which,the backfat thickness of Jinjiang steers in group C was the lowest (2.01 cm),while the eye muscle area gradually increased,and the maximum value of group E was 81.04 cm~2. 2) With the increase of the dietary NE_(mf)level,the pH_(45) minof longissimus dorsi gradually decreased,and it in groups D and E was significantly lower than that in group A (P < 0. 05); the shear force of longissimus dorsi in groups C,D and E was significantly lower than that in groups A and B (P<0.05). However,dietary energy level had no significant effects on the pH_(24h),meat color [lightness (L~*),redness (a~*) and yellowness (b~*) values],dripping loss and cooking loss of longissimus dorsi (P>0.05).3) The crude fat and crude protein contents in longissimus dorsi of Jinjiang steers in group C were significantly higher than those in the other groups (P<0.05),but there were no significant differences in the moisture and ash contents in longissimus dorsi of Jinjiang steers among groups (P > 0.05). 4) The serum growth hormone content in group E was significantly higher than that in groups A,B and C (P<0.05). The serum leptin content in group C was significantly lower than that in groups A,B and D (P<0.05),and serum adiponectin content was significantly higher than that in other groups (P < 0. 05). In conclusion,under the conditions of this experiment,combined with the results of carcass traits,meat quality and serum endogenous hormone contents,the energy level of diet C (NE_(mf)level = 6.74 M J/kg) is relatively suitable for the energy level requirement for the production of high-quality beef of Jinjiang steers.
