中国农业科学 ›› 2015, Vol. 48 ›› Issue (14): 2827-2838.doi: 10.3864/j.issn.0578-1752.2015.14.014

• 畜牧·兽医·资源昆虫 • 上一篇    下一篇

放牧与舍饲条件下山羊肌肉发育和抗氧化能力变化研究

黄金玉1,2,焦金真1,2,冉涛1,2,汤少勋1,康劲翮1,谭支良1   

  1. 1中国科学院亚热带农业生态研究所/中国科学院亚热带农业生态过程重点实验室/湖南省农业生态工程重点实验室,长沙 410125
    2中国科学院大学,北京 100049
  • 收稿日期:2014-09-18 出版日期:2015-07-16 发布日期:2015-07-16
  • 通讯作者: 谭支良,E-mail:zltan@isa.ac.cn
  • 作者简介:黄金玉,E-mail:yuqionger2012@126.com
  • 基金资助:
    国家自然科学基金(31320103917)、中国科学院外籍青年科学家计划(2013Y2GA0010)、中央驻湘科研机构技术创新发展专项(2013TF3006)

Study on the Developmental Changes of Meat and Antioxidant Capacity of Grazing and House-Feeding Goats

HUANG Jin-yu1,2, JIAO Jin-zhen1,2, RAN Tao1,2, TANG Shao-xun1, KANG Jin-he1, TAN Zhi-liang1   

  1. 1Institute of Subtropical Agriculture, Chinese Academy of Sciences / Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, the Chinese Academy of Sciences / Key Laboratory of Agro-ecological Processes in Subtropical Region of Hunan Province, Changsha 410125
    2University of Chinese Academy of Sciences, Beijing 100049
  • Received:2014-09-18 Online:2015-07-16 Published:2015-07-16

摘要: 【目的】探究在放牧、舍饲条件下幼龄山羊肌肉品质及抗氧化能力的发育性变化。【方法】选择体况良好、体重相近的经产湘东黑山羊母羊25头,进行同期发情处理,怀孕后产羔,获得36头羔羊,不记公母。出生后20 d内所有羔羊均仅喂以母乳。在0、7、14 d,每个时间点分别随机选取4头屠宰;21 d时,将剩余的24头羔羊随机分为放牧组和舍饲组,每组12头,除母乳外,放牧组以牧草为食,舍饲组补给精料及与放牧组相同的牧草,40 d断奶;在42、56、70 d时,两组每个时间点分别随机选取4头进行屠宰。称量宰前活重、胴体重,采集背最长肌,测定肌肉中粗蛋白(CP)、肌内脂肪(IMF)、氨基酸(AA)、脂肪酸(FA)的组成和含量及主要抗氧化酶活性,包括过氧化氢酶(CAT)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、还原型谷胱甘肽(GSH)和总抗氧化能力(T-AOC)。【结果】(1)羔羊宰前活重、胴体重随日龄显著增加(P<0.05),相较于舍饲羊,放牧羊宰前活重较低(P>0.05),但胴体重较高(P>0.05)。(2)无论是放牧还是舍饲,肌肉干物质中CP水平随日龄呈线性增加趋势(P<0.05),IMF含量呈升高趋势(P>0.05);相较于舍饲羊,放牧羊CP水平较低(P>0.05),IMF含量明显较高(P<0.05)。(3)肌肉中氨基酸总量(TAA)、成人必需氨基酸(AEAA)、婴儿必需氨基酸(BEAA)在不同日龄间没有显著差异(P>0.05),但TAA随日龄有升高趋势(P>0.05),鲜味氨基酸(FAA)随日龄呈显著增加趋势(P<0.05);相较于舍饲羊,放牧羊TAA、AEAA、FAA含量较低,BEAA则较高,但均差异不显著(P>0.05)。(4)肌肉中饱和脂肪酸(SFA)在放牧条件下随日龄变化不显著(P>0.05),舍饲时呈二次曲线变化(P<0.05),单不饱和脂肪酸(MUFA)显著降低(P<0.05),多不饱和脂肪酸(PUFA)、必需脂肪酸(EFA)显著升高(P<0.05);与舍饲羊相比,放牧羊SFA、PUFA、EFA比例较低(P>0.05),MUFA较高(P<0.05)。(5)随着年龄的增长,CAT、SOD活力在0—14 d呈升高趋势,14—42 d有所降低,之后继续呈增加趋势,整体变化不显著(P>0.05),GSH-Px活力呈显著性二次曲线变化(P<0.05),T-AOC呈升高趋势(P<0.05),GSH含量在放牧组呈线性降低趋势(P<0.05),在舍饲组变化不显著(P>0.05);相较于舍饲羊,放牧羊SOD、GSH-Px、T-AOC活力较高(P>0.05),CAT活力较低(P>0.05),GSH含量则显著较低(P<0.05)。【结论】随着年龄的增长,山羊宰前活重、胴体重显著增加,但饲养方式(放牧、舍饲)对其影响不显著,而肌肉中CP水平逐渐增加,IMF沉积呈升高趋势,氨基酸、脂肪酸的组成一致,含量有差异,相应指标是舍饲羊优于放牧羊。整体来看,舍饲羊肉质稍优于放牧羊。但山羊肌肉抗氧化能力随日龄逐渐增强,且放牧羊高于补饲羊。因此,根据当地和养殖场的条件,以及幼龄山羊肉质阶段性发育规律,合理选择放牧、舍饲等饲养方式,如可以将二者结合或轮换等,以获得更好的肉质和更大的经济效益。

关键词: 湘东黑山羊, 背最长肌, 放牧, 舍饲, 肉质, 抗氧化能力

Abstract: 【Objective】The objective of this experiment is to explore developmental changes of meat quality and antioxidant capacity of grazing and house-feeding goats. 【Method】Thirty-six kid goats were collected from 25 Xiangdong black female goats with estrus synchronization. All postnatal goats were fed on goat milk in 20 days. At 0, 7, and 14 d, 4 kid goats were slaughtered, respectively. And then the rest of these kids were assigned into two groups of 12 per group based on different feeding systems-grazing and house-feeding. At 21 d, the grazing group started to feed goat milk and forage, and the house-feeding group was fed on goat milk and a diet of forage supplemented with concentrate starter. All kids were weaned at 40 days. At 42, 56, and 70 d, 4 kids were slaughtered, respectively, in each group. The longissimus dorsi muscle from all 36 kids were collected and crude protein, intramuscular fat, amino acids, fatty acids contents and antioxidant enzymes (catalase, superoxide dismutase, glutathione peroxidase, reduced glutathione and total antioxidant capacity ) activities were determined.Result】The live weight and carcass weight of kids increased significantly with age (P<0.05). When compared with house-feeding kids, grazing kids had lower (P>0.05) live weight, but higher (P>0.05) carcass weight. The content of crude protein in dry matter showed a linear increasing trend in two groups (P<0.05), while intramuscular fat (IMF) showed an increasing trend (P>0.05).Grazing kids presented lower contents of crude protein (P>0.05) and higher IMF than house-feeding kids. The level of total amino acids (TAA), adult essential amino acids (AEAA) and baby amino acids (BEAA) were not affected significantly by age, whereas both TAA (P>0.05) and flavor amino acids (FAA) (P<0.05) showed an increasing trend. Likewise, TAA, AEAA and BEAA were not affected remarkably by feeding system; grazing kids had lower TAA, AEAA and FAA, but higher BEAA than house-feeding kids (P>0.05). (4) Age did not affect saturated fatty acids (SFA) in grazing kid, but had a quadratic effect on SFA in rearing kids; monounsaturated fatty acids (MUFA) gradually decreased (P<0.05), while polyunsaturated fatty acids (PUFA) and essential fatty acids (EFA) remarkably increased (P<0.05) with age. Compared to house-feeding group, the grazing group showed lower levels of SFA, PUFA and EFA (P>0.05), but higher level of MUFA (P<0.05). Age did not have an effect on the active levels of catalase (CAT) and superoxide dismutase (SOD), however, had a quadratic effect on glutathione peroxidase (GSH-Px) (P<0.05), and an increasing effect on total antioxidant capacity (T-AOC) (P<0.05); reduced glutathione (GSH) in grazing group showed a linear decreasing trend (P<0.05), but no significant difference in house-feeding group (P>0.05).【Conclusion】Whatever the feeding system, kid goats at different ages had an increasing live weight and carcass weight, and in longissimus dorsi muscle, crude protein gradually increased, intramuscular fat showed an increasing trend, and amino acids and fatty acids contents fluctuated with age. Meanwhile, the grazing kids presented a relatively lower level of meat quality while higher antioxidant capacity than the house-feeding kids. Consequently, for producing the desirable chevon and achieving higher profit, an adaptive feeding system should be selected according to the natural environment, feedlot condition and the development profile of the muscle.

Key words: Xiangdong black goats, longissimus dorsi muscle, grazing, house-feeding, meat quality, antioxidant capacity