不同精粗比饲粮中添加壳聚糖对体外瘤胃发酵甲烷产量和发酵特性的影响

本试验旨在利用长期人工瘤胃系统——Rusitec系统研究不同精粗比饲粮中添加壳聚糖对体外瘤胃发酵甲烷产量和发酵特性的影响。采用2×2两因子试验设计,2个因子分别为饲粮精粗比[30∶70(低精料饲粮)和70∶30(高精料饲粮)]和是否添加壳聚糖(0和1 500 mg/罐),共构成4组,每组4个重复。结果表明:与低精料饲粮相比,高精料饲粮显著降低了甲烷产量,中性洗涤纤维和粗蛋白质的降解率,发酵液乙酸和丁酸含量、乙酸/丙酸、氨氮浓度(P<0.05),显著提高了总产气量和丙酸含量(P<0.05);添加壳聚糖显著降低了甲烷产量和总产气量、粗蛋白质的降解率、发酵液乙酸和丁酸含量、乙酸/丙酸、氨氮浓度(P<0.05),显著提高了丙酸含量(P<0.05);在甲烷产量和总产气量,粗蛋白质的降解率,0、6 h发酵液氨氮浓度,0、12 h发酵液乙酸/丙酸上,2个因子存在互作(P<0.05),高精料饲粮中添加壳聚糖对甲烷产量和总产气量、粗蛋白质降解率、发酵液氨氮浓度的降低幅度大于低精料饲粮,对总挥发性脂肪酸浓度和乙酸/丙酸的降低幅度小于低精料饲粮。以上结果表明,改变饲粮的精粗比和添加壳聚糖均能够改变瘤胃发酵模式,且二者之间存在互作,壳聚糖在精粗比为70∶30的饲粮中添加效果优于精粗比为30∶70的饲粮。     

不同精粗比饲粮中添加凝结芽孢杆菌对绵羊羔羊生长性能和消化代谢的影响

本试验旨在研究不同精粗比条件下饲粮添加凝结芽孢杆菌(BC)对绵羊羔羊生长性能和消化代谢的影响。试验采用2×2因子完全随机设计,2个因素分别为精粗比[40∶60(低精料)、70∶30(高精料)]和BC[不添加和添加1.0×1010CFU/kg BC]。选取48只4月龄的杜泊×小尾寒羊F1代公羔,按体重随机分为4个组,分别饲喂低精料饲粮(LD组)、添加BC低精料饲粮(LD+BC组)、高精料饲粮(HD组)、添加BC高精料饲粮(HD+BC组),每组12只。生长性能试验共计70 d,其中预试期10 d,正试期60 d;消化代谢试验共计7 d,其中适应期4 d,取样期3 d。结果显示：1)24只饲喂高精料饲粮羔羊的末重(FBW)和平均日增重(ADG)显著或极显著高于24只饲喂低精料饲粮羔羊(P<0.05或P<0.01),并且料重比(F/G)极显著低于24只饲喂低精料饲粮羔羊(P<0.01);24只饲喂添加BC饲粮羔羊的ADG显著高于24只饲喂不添加BC饲粮羔羊(P<0.05)。2)24只饲喂高精料饲粮羔羊对干物质(DM)、有机物(OM)、中性洗涤纤维(NDF)的表观消化率极...     

不同精粗比饲粮中添加凝结芽孢杆菌对绵羊羔羊瘤胃发酵和免疫功能的影响

本试验旨在研究不同精粗比饲粮中添加凝结芽孢杆菌（BC）对绵羊羔羊生长性能、瘤胃发酵和免疫功能的影响。试验采用2×2双因子完全随机设计,2个因素分别为精粗比[40∶60（低精料）、70∶30（高精料）]和BC[不添加和添加1.0×1010CFU/kg BC]。选取48只体重相近的4月龄杜泊×小尾寒羊F1代公羔,随机分为4个组,分别饲喂低精料饲粮（LD组）、添加BC的低精料饲粮（LD+BC组）、高精料饲粮（HD组）、添加BC的高精料饲粮（HD+BC组）,每组12只。预试期10 d,正试期60 d。结果显示：1)24只饲喂高精料饲粮的羔羊瘤胃内pH,氨态氮、乙酸、异丁酸浓度以及乙丙比值显著低于24只饲喂低精料饲粮的羔羊（P<0.05）,丙酸、戊酸和总挥发性脂肪酸浓度显著高于24只饲喂低精料饲粮的羔羊（P<0.05）;24只饲喂添加BC饲粮的羔羊瘤胃内丙酸浓度显著高于24只饲喂未添加BC饲粮的羔羊（P<0.05）。饲粮精粗比和BC之间在瘤胃发酵参数上不存在显著的交互作用（P>0.05）。2)24只饲喂高精料饲粮的羔羊瘤胃内淀粉酶和蛋白酶活性显著高于24只饲喂低精料饲粮的...     

不同精粗比饲粮对牦牛瘤胃内环境的影响

旨在研究不同精粗比饲粮对西藏牦牛瘤胃内环境的影响.选取3周岁、平均体重(154.8±13.6)kg、健康无病的牦牛20头随机分为低精料组和高精料组,每组10头,公母各半,分别饲喂低精料(精粗比40∶60)和高精料(精粗比60 ∶ 40)饲粮,预试期10d,正试期90d(8、9和10月).结果:饲粮精料水平的提高显著降低...     

饲粮精粗比和添加硫胺素对奶牛体外瘤胃发酵参数及菌群结构的影响

本试验采用体内逐渐提高奶牛饲粮精料水平与体外批次培养相结合的方法建立亚急性瘤胃酸中毒模型,旨在研究不同精粗比饲粮对硫胺素微生物净合成量的影响,以及添加硫胺素对亚急性瘤胃酸中毒状态下奶牛体外瘤胃发酵参数和菌群结构的影响。试验采用2×4因子完全随机试验设计,因素1为硫胺素添加水平,设0和180 mg/kg 2个水平,因素2为饲粮的精粗比,设4个水平,分别为40∶60、50∶50、60∶40、70∶30。试验共设8个处理,每个处理3个重复,于体外培养0、3、6、9、12 h后采集样品。结果表明:随着精料水平的提高,培养液中硫胺素的微生物净合成量呈先升高后降低的趋势,其中精粗比为40∶60、70∶30的饲粮组培养液中硫胺素的微生物净合成量在3、9、12 h时均显著或极显著低于精粗比为50∶50和60∶40的饲粮组(P<0.05或P<0.01)。在12 h时,随着精料水平的提高,培养液pH极显著降低(P<0.01),精粗比为70∶30的饲粮组发生亚急性瘤胃酸中毒;与未添加组相比,添加硫胺素组培养液pH极显著提高(P<0.01)。在6、9、12 h时,精粗比为60∶40和70∶30的饲粮组培养液中乳酸浓度极显著高于精粗比为40∶60的饲粮组(P<0.01);在3、9 h时,添加硫胺素可极显著降低培养液中乳酸浓度(P<0.01)。饲粮精粗比对培养液中溶纤维丁酸弧菌和反刍兽新月形单胞菌的数量无显著影响(P>0.05),但可显著或极显著影响培养液中牛链球菌、乳酸杆菌和埃氏巨型球菌的数量(P<0.05或P<0.01);与未添加组相比,添加硫胺素组培养液中牛链球菌的数量降低了3.84%(P<0.01),埃氏巨型球菌的数量提高了4.02%(P<0.01),但乳酸杆菌、溶纤维丁酸弧菌和反刍兽新月单胞菌的数量未发生显著变化(P>0.05)。由此得出,在高精料饲粮条件下,瘤胃中硫胺素的微生物净合成量降低,发生亚急性瘤胃酸中毒;添加硫胺素可通过提高瘤胃pH,降低乳酸浓度,以及调节瘤胃菌群结构来缓解亚急性瘤胃酸中毒。     

不同铜水平饲粮对舍饲滩羊生长性能、屠宰性能及肉品质的影响

本试验旨在研究不同铜水平饲粮对舍饲滩羊生长性能、屠宰性能及肉品质的影响,为生产高端羊肉提供科学、可靠的理论依据。选取断奶后、平均体重为20kg左右的健康无疾病的滩羊40只,随机分为4组,每组10只。对照组饲喂基础饲粮,不额外添加铜,饲粮中铜含量为9.0mg/kg;试验I、Ⅱ、Ⅲ组分别饲喂在基础饲粮中添加3.0、5.5和7.0mg/kg铜。预试期为10d,正试期为60d。结果表明:1)4组间舍饲滩羊的初重、末重和平均日增重均无显著差异(P>0.05)。2)4组间舍饲滩羊的体长、体高、胸围均无显著差异(P>0.05)。试验Ⅰ组舍饲滩羊的体高相对增长量显著高于对照组和试验Ⅱ组(P<0.05)。3)4组间舍饲滩羊的宰前活重、胴体重、骨重、胴体脂肪重、GR值、眼肌面积、骨肉比以及胴体产肉率均无显著差异(P>0.05)。试验Ⅰ、Ⅱ组舍饲滩羊的净肉重显著高于对照组(P<0.05),试验Ⅲ组舍饲滩羊的尾部脂肪重显著高于对照组(P<0.05)。4)4组间舍饲滩羊的肌肉pH、初水分、失水率、滴水损失和熟肉率均差异不显著(P>0.05)。试验Ⅰ组舍饲滩羊的肉色红度值显著高于对照组和试验Ⅱ、Ⅲ组(P<0.05),试验Ⅰ、Ⅱ组舍饲滩羊的肌肉剪切力显著高于试验Ⅲ组(P<0.05)。综上所述,饲粮中添加适宜水平铜可提高舍饲滩羊的屠宰性能和肉品质,本试验条件下,以添加3.0mg/kg铜(饲粮铜含量为12.0mg/kg)为宜。     

饲粮精粗比对南江黄羊瘤胃体外发酵的影响

本试验旨在研究饲粮不同精粗比对南江黄羊瘤胃体外发酵的影响。试验以3只装有永久性瘤胃瘘管的健康南江黄羊[平均体重为(25.48±1.48)kg]作为瘤胃液供体动物,采用单因素试验设计,试验饲粮精粗比分别为10∶90(10C组)、30∶70(30C组)、50∶50(50C组)、70∶30(70C组)、90∶10(90C组)。结果表明:随着饲粮精粗比的提高,培养液中pH逐渐下降,发酵后70C、90C组均显著低于10C、30C组(P<0.05);精粗比对氨态氮浓度和总挥发性脂肪酸浓度影响不显著(P>0.05);微生物蛋白浓度随着精粗比的提高逐渐升高,其中90C组显著高于其他4组(P<0.05);有机物发酵率随着精粗比的提高显著提高(P<0.05);乙酸与丙酸的比值随着精粗比的提高逐渐下降。由此可知,本试验条件下,高精料饲粮对南江黄羊体外发酵有显著的影响,随着精料比例的升高,微生物蛋白合成量增加,瘤胃发酵的能量利用效率提高。     

酵母甘露寡糖对蒙古绵羊生长性能、血清免疫和炎症及抗氧化指标的影响

本试验旨在研究酵母甘露寡糖对蒙古绵羊生长性能、血清免疫和炎症及抗氧化指标的影响。选用体况良好、体重[(28.91±1.81)kg]相近的18只蒙古绵羊,随机分为3组(每组6只),对照组饲喂基础饲粮,甘露寡糖组和瘤胃素组在对照组饲粮的基础上在精料中分别添加0.1%酵母甘露寡糖和0.015%的瘤胃素。试验期为70 d,其中预试期10 d,正试期60 d。第1~30天,饲粮精粗比为4∶6,第31~60天饲粮精粗比逐步过渡到7∶3。于正试期第1天、第30天和第60天空腹称重并采集血清,检测血清免疫球蛋白M(IgM)、脂多糖结合蛋白(LBP)、白细胞介素6(IL-6)、血清淀粉样蛋白A(SAA)和一氧化氮(NO)的浓度,以及总抗氧化能力(TAOC)、总超氧化物歧化酶(T-SOD)和谷胱甘肽过氧化物酶(GSH-Px)活性。结果表明:1)与对照组相比,饲粮添加甘露寡糖和瘤胃素均能显著提高高精料饲养模式下蒙古绵羊的生长性能,表现为体重(第60天)、平均日增重显著增加(P0.05),料重比显著降低(P0.05),且甘露寡糖组在第1~30天的阶段日增重显著高于对照组和瘤胃素组(P0.05),第31~60天,瘤胃素组的阶段日增重显著高于对照组(P0.05)。2)第30天,甘露寡糖组绵羊血清中的IgM浓度、LBP浓度和T-SOD活性显著高于对照组(P0.05);第60天,与对照组相比,甘露寡糖组绵羊血清中SAA浓度显著升高(P0.05),血清T-AOC和GSH-Px活性显著降低(P0.05),瘤胃素组血清T-AOC也显著降低(P0.05)。综合得出,添加酵母甘露寡糖能改善饲喂高精料饲粮蒙古绵羊的生长性能、血清免疫功能和抗氧化能力,与添加瘤胃素有相似的效果,且在精粗比4∶6时效果较好。     

日粮不同精粗比与中草药添加剂对滩羊增重、肉理化性能、血液生化和免疫指标的影响

试验探讨在不同精粗比日粮中添加中草药对滩羊增重、肉理化性能、血液生化及免疫指标的影响。试验1组日粮精粗比为1.59,不添加中草药添加剂;试验2、3、4组日粮精粗比分别为1.59、2.31、0.98,且添加0.65%中草药添加剂。结果表明:各试验组间增重、日增重差异不显著(P>0.05)。试验3组增重和日增重高于试验2组和试验4组;饲喂中草药添加剂的试验2、3、4组IgA、IgG、IgM、WBC、LYM指标均高于不添加中草药添加剂的试验1组,且试验4组IgA、IgG、IgM、WBC、LYM均高于其他各组。试验90 d,试验4组与试验3组之间白细胞差异显著(P<0.05),试验30 d与试验90 d,试验3组淋巴细胞差异显著(P<0.05),试验4组淋巴细胞差异显著(P<0.05),中草药添加剂与合适的精粗比日粮可显著提高滩羊的血液生化指标和免疫水平;试验4组与试验3组间熟肉率差异显著(P<0.05),试验3组与其他各组pH值差异显著(P<0.05),且在各组中最高。说明滩羊育肥期日粮中添加0.65%中草药添加剂精粗比为0.98对其增重、肉理化性能、血液生化及免疫指标效果较好。     

烟酸对高精料饲粮肥育肉牛生长性能及血清生化指标的影响

本文旨在研究高精料饲粮中添加烟酸对肥育肉牛生长性能、养分表观消化率和血清生化指标的影响。选择体况良好、体重(402.2±25.4)kg的杂交公牛[西门塔尔()×中国黄牛(♀)]24头,随机分成4组,每组6头牛。Ⅰ组、Ⅱ组、Ⅲ组和Ⅳ组在精料中分别添加200、400、600和800 mg/kg的烟酸(以干物质计),饲粮精粗比85∶15,试验期56 d。结果表明:补饲烟酸对干物质采食量没有显著影响(P>0.05),Ⅳ组的生长性能优于其余3组。Ⅳ组饲粮粗蛋白质、粗脂肪的表观消化率显著地高于其余3组(P<0.05),酸性洗涤纤维表观消化率显著地高于Ⅲ组(P<0.05),中性洗涤纤维表观消化率显著地高于Ⅱ组和Ⅲ组(P<0.05)。烟酸水平对血清葡萄糖、甘油三酯和β-羟基丁酸的浓度无显著影响(P>0.05),Ⅳ组血清非酯化脂肪酸浓度极显著地高于其余3组(P<0.01)。结果提示,高精料饲粮中补饲烟酸可提高肥育肉牛生长性能和养分表观消化率,本试验条件下以精料中添加800 mg/kg的烟酸效果较好。     

Effects of dietary concentrate level and chromium-methionine supplementation on ruminal fermentation,and ruminal bacterial and fatty acid composition in Tan lambs北大核心CSCD

This study evaluated the effects of dietary concentrate level and chromium methionine(Cr-Met)supplementation on ruminal fermentation and fatty acid composition, and ruminal bacteria abundance in Tan lambs. Forty male Tan lambs [(21.00±1.23) kg body weight, 5 months of age] were randomly assigned to four treatment groups with 10 lambs in each treatment. The treatments were: a low-concentrate (LC) diet (concentrate:forage, 35:65) without Cr-Met supplementation; a high-concentrate (HC) diet (concentrate:forage, 55:45) without Cr-Met supplementation; groups fed the HC diet with 0.75 or 1.50 g·d-1·lamb-1 Cr-Met (HCM and HCH, respectively). Ruminal fluid was collected on day 65 with an oral stomach tube about 3 h after the morning feed and samples used for fermentation analysis, fatty acid composition determination and bacterial DNA extraction. It was found that: 1) Ruminal pH, acetate proportion and acetate:propionate were greater (P<0.05) with the LC diet whereas microbial crude protein, propionate and valerate proportions were greater (P<0.05) with the HC diet. The acetate:propionate was greater (P<0.05) in the HCM group than in the HC group. 2) For the HC diet, the DNA abundances of Butyrivibrio fibrisolvens vaccenic acid subgroup (Butyrivibrio VA) and Ruminococcus flavefaciens were decreased (P<0.05), compared with the LC diet, whereas the DNA abundance of Anaerovibrio lipolytica was increased (P<0.05). For lambs fed the HC diet, DNA abundances of B. fibrisolvens stearic acid subgroup, Butyrivibrio VA, Butyrivibrio proteoclasticus, and A. lipolytica showed a linear decrease (P<0.05) with increasing Cr-Met supplementation level; However, the DNA abundance of R. flavefaciens showed a linear increase (P<0.05). 3) Compared with the LC group, the concentrations of t11 C18:1, trans C18:1, c9t11 CLA, t10c12 CLA, C18:2n6, and C18:3n3 were decreased by the HC diet without Cr-Met supplementation whereas the concentration of C18:0 was increased. There was a linear increase in t11 C18:1 and trans C18:1 with increasing Cr-Met supplementation level in lambs fed the HC diet. The results suggest that the HC diet inhibited the growth of ruminal bacteria involved in the ruminal biohydrogenation process, and the addition of Cr-Met had a potentially positive effect on conjugated linoleic acid (CLA) synthesis in body tissue. © 2022, Editorial Office of Acta Prataculturae Sinica. All rights reserved.     

饲粮添加亚麻油和亚麻籽对绒山羊羔羊屠宰性能、器官生长发育及肉品质的影响

本试验旨在研究舍饲条件下饲粮添加亚麻油和亚麻籽对绒山羊羔羊屠宰性能、器官生长发育及肉品质的影响。试验采用单因素完全随机试验设计,选择体重为(18.60±0.10)kg的60只4月龄阿尔巴斯断奶羯羔,随机分为对照组(CON组)、亚麻油组(LSO组)和亚麻籽组(HLS组)3个组,每组4个重复,每个重复5只羊。在育肥前期(1~30 d)、中期(31~60 d)和后期(61~90 d),CON组饲喂基础饲粮,LSO组分别饲喂添加2.0%、2.0%和2.5%亚麻油的试验饲粮,HLS组分别饲喂添加5.5%、5.5%和7.0%热处理亚麻籽(120℃翻炒10 min)的试验饲粮。预试期14 d,正试期90 d。结果表明:1)LSO组羔羊的胴体重、屠宰率、肾脂重、尾脂重和脂肪组织重显著高于HLS组(P<0.05)。2)与CON组相比,LSO组羔羊的蹄、毛皮和头+蹄+毛皮+血液重显著增加(P<0.05),而HLS组显著降低(P<0.05)。与CON组和HLS组相比,LSO组羔羊的心脏、肾脏和内脏器官重显著增加(P<0.05),肺脏和胰脏指数显著降低(P<0.05)。与CON组相比,LSO组和HLS组羔羊的网胃重显著降低(P<0.05),HLS组羔羊的瓣胃重显著降低(P<0.05)。3)HLS组羔羊背最长肌的蒸煮损失和红度值显著高于LSO组(P<0.05),亮度值显著低于LSO组(P<0.05)。与CON组相比,LSO组羔羊背最长肌的黄度值显著增加(P<0.05),而HLS组显著降低(P<0.05)。与CON组相比,LSO组和HLS组羔羊的臂三头肌干物质、背最长肌粗蛋白质含量显著增加(P<0.05)。由此可见,饲粮添加亚麻油降低了绒山羊羔羊外部组织器官、内脏器官和消化道占体重的比例,屠宰性能较好,脂肪沉积也有所增加;饲粮添加亚麻籽的羔羊肉色和肌肉营养价值优于饲粮添加亚麻油的羔羊。     

饲养方式对滩羊羔羊肌肉及脂肪组织中脂肪酸组成的影响

为探究饲养方式对滩羊羔羊肌肉和脂肪组织中脂肪酸组成的影响,试验选择24只健康且体重相近（14.16 kg±0.58 kg）的2月龄滩羊羔羊随机分成舍饲组和放牧组,每组12只,于4月龄屠宰取其背最长肌、股二头肌、膈肌、皮下脂肪、肾周脂肪、尾部脂肪,用气相色谱仪测定脂肪酸含量。结果表明：①在肌肉组织饱和脂肪酸中,与放牧组相比,舍饲组滩羊羔羊股二头肌丁酸、棕榈酸含量显著提高（P<0.05）,膈肌辛酸、月桂酸、肉豆蔻酸含量显著降低（P<0.05）。在肌肉组织不饱和脂肪酸中,与放牧组比较,舍饲组滩羊羔羊背最长肌棕榈油酸、花生四烯酸含量显著降低（P<0.05）,γ-亚麻酸、α-亚麻酸含量显著提高（P<0.05）,二十碳五烯酸（EPA）、n-3多不饱和脂肪酸（n-3 PUFA）极显著提高（P<0.01）;股二头肌花生四烯酸含量显著降低（P<0.05）,十七碳一烯酸、α-亚麻酸、EPA、n-3 PUFA含量极显著提高（P<0.01）;膈肌棕榈油酸含量显著降低（P<0.05）。②在脂肪组织饱和脂肪酸中,与放牧组比较,舍饲滩羊羔羊皮下脂肪十一碳酸、十五碳酸含量显著降低（P<0.05）,十三碳酸含量极显著降低（P<0.01）;肾周脂肪葵酸、肉豆蔻酸含量显著降低（P<0.05）,丁酸、硬脂酸含量极显著提高（P<0.01）;尾脂十一碳酸含量显著降低（P<0.05）。在脂肪组织不饱和脂肪酸中,与放牧组比较,舍饲滩羊羔羊皮下脂肪十八碳二烯酸含量极显著提高（P<0.01）,肉豆蔻油酸、棕榈油酸、γ-亚麻酸含量极显著降低（P<0.01）;肾周脂肪十八碳一烯酸、α-亚麻酸、n-3PUFA含量显著提高（P<0.05）,肉豆蔻油酸含量显著降低（P<0.05）,十七碳一烯酸、二十碳二烯酸、十八碳二烯酸含量极显著提高（P<0.01）;尾脂肉豆蔻油酸、棕榈油酸含量显著降低（P<0.05）,十八碳二烯酸含量极显著提高（P<0.01）。综上,不同饲养方式对滩羊羔羊肌肉和脂肪组织脂肪酸含量存在一定影响,舍饲滩羊羔羊股二头肌中饱和脂肪酸含量及肾周脂肪中不饱和脂肪酸含量显著高于放牧滩羊羔羊。     

Effects of Different Types of N-carbamylglutamate on the Growth Performance,Serum Biochemical Indexes and Fat Distribution of Tan Sheep

The objective of the present experiment was to determine the effect of different types of N-carbamoylglutamate on growth performance,serum biochemical indexes and fat distribution of Tan sheep. Sixty male Tan lambs with average weight of (20.14±0.31)kg and similar age were randomly assigned three groups with five replications per group and 4 lambs per replication. The lambs in control group were fed basal diet, while lambs in test groups were fed diets containing 0.1% NCG and 0.1% RP-NCG,respectively. The results showed that:① Comparing with control group,the ADG was significantly improved (P<0.05) and F/G was significantly decreased (P<0.05) when 0.1% NCG or 0.1% RP-NCG were supplemented,while there was no significant difference between two experimental groups (P>0.05).② Dietary supplemented with 0.1% NCG or 0.1% RP-NCG significantly decreased the serum urea nitrogen (P<0.05),but there were no significant differences in serum total protein,creatinine content and creatine kinase activity (P>0.05).③ The ration of meat weight to carcass weight of two experimental groups was significantly improved (P<0.05).As 0.1% NCG or 0.1% RP-NCG were supplemented in the diets, the content of subcutaneous fat and GR value were significantly decreased (P<0.05),and the content of intramuscular fat (IMF) was significantly increased (P<0.05).In conclusion,dietary supplemented with 0.1% NCG or 0.1% RP-NCG could improve the growth performance and slaughter performance while there was no significant difference between NCG and RP-NCG.     

羔羊日粮精粗比对其肉及脂肪组织中脂肪酸组成的影响

为了研究不同精粗比日粮对广河羊羔肉品质的影响,在广河县羔羊肉生产区,选择不同精粗比饲喂的6月龄健康陶寒杂交(陶赛特羊♂×小尾寒羊♀)断奶去势公羔各3只进行屠宰,取股二头肌、背最长肌、肱二头肌3个部位肌肉和肾周脂肪、皮下脂肪、尾部脂肪3个部位脂肪,用气象色谱法分析其脂肪酸的种类及含量。结果表明,在所有组织中均检测出38种脂肪酸,其中饱和脂肪酸17种,不饱和脂肪酸21种。脂肪组织中饲喂低精粗比日粮的亚油酸(C18∶2n6c)、α-亚麻酸(C18∶3n3)、饱和脂肪酸(SFA)、多不饱和脂肪酸(PUFA)及其与饱和脂肪酸比值(P/S)、n3系多不饱和脂肪酸和n6系多不饱和脂肪酸均显著高于饲喂高精粗比日粮(P<0.05);饲喂低精粗比日粮的所有组织中花生四烯酸(C20∶4)的含量显著高于饲喂高精粗比日粮(P<0.05);与饲喂高精粗比日粮的羊羔肉相比,饲喂低精粗比日粮既节省了生产成本又明显改善和提高了羊羔肉中脂肪酸的营养价值。     

Antioxidative and oxidative status in muscles of pigs fed rapeseed oil, vitamin E, and copper

The susceptibility of a given muscle tissue to lipid oxidation may not only depend on the presence of unsaturated fatty acids and the balance between antioxidants and prooxidants, but also on the composition of the skeletal muscle. In the present study, the effects of dietary supplementation of vitamin E (dl-alpha-tocopheryl acetate) and copper in combination with a high level of monounsaturated fatty acids were examined with regard to the antioxidant concentration and the susceptibility to lipid oxidation of two muscles, longissimus (LD) and psoas major (PM), representing different oxidative capacity. In addition, fatty acid profiles of the backfat and the intramuscular lipids, as well as fresh meat quality traits, were studied. Pigs were allotted to a 3x3 factorial experiment with three levels of dl-alpha-tocopheryl acetate (0, 100, and 200 mg/kg of feed) and three levels of copper (0, 35, and 175 mg/kg of feed) added to a diet containing 6% rapeseed oil. A basal diet (without rapeseed oil) was added to the experimental design, giving a total of 10 dietary treatments. Muscle alpha-tocopherol concentrations increased (P<.001) with increasing dl-alpha-tocopheryl acetate in the feed. The antioxidative status was higher in PM than in LD, when considering the concentration of alpha-tocopherol (P<.001) and the activity of antioxidant enzymes (superoxide dismutase, P<.001; glutathione peroxidase, P = .06). Supplemental copper did not give rise to any deposition of copper in muscle tissue or backfat, but the antioxidant status of PM increased. The susceptibility to lipid oxidation was reduced in LD with increasing dietary dl-alpha-tocopheryl acetate and in PM with increasing dietary copper. Supplemental dl-alpha-tocopherol acetate improved the water-holding capacity of LD (P = .005) and PM (P = .003). The fatty acid composition of the backfat and the triglyceride fraction of the intramuscular fat became more unsaturated with the addition of rapeseed oil to the feed. Higher intakes of monounsaturated fatty acids due to the rapeseed oil were also reflected in the phospholipid fraction of the intramuscular fat, but no influence on the proportion of saturated fatty acids was seen. The susceptibility to lipid oxidation of PM was lower for pigs on the rapeseed oil-based diet than for those on the basal diet. The energy metabolic status of the muscles and the accumulation of calcium by the sarcoplasmic reticulum were not influenced by the dietary treatments, but there were differences between muscle types. The addition of rapeseed oil to the diet reduced the muscular content of glycogen (LD, P = .02; PM, P = .06) and elevated the plasma concentration of free fatty acids (P = .05). Overall, dietary fat, dl-alpha-tocopherol acetate, and copper affected the oxidative status of pig muscles, and the results differed depending on muscle type.     

妊娠后期母羊饲粮营养水平对产后羔羊生长性能、器官发育和血清抗氧旨标的影响

本试验在干物质采食量一致条件下,改变精料补充料与饲草比例调控妊娠后期母羊饲粮营养水平,旨在研究其对产后羔羊生长性能、器官发育和血清抗氧化指标的影响.选用健康、年龄[(11.0±1.0)月龄]和体重[(44.43±2.20) kg]相近、妊娠90 d的怀双羔初产湖羊母羊66只,分为3组,每组22只.以干物质为基础按照精料补充料与饲草比例分别为5∶5(5∶5组)、4∶6(4∶6组)和3∶7(3∶7组)饲喂至产羔,产羔后各组母羊饲喂相同的全混合日粮,自由采食.出生10、60 d屠宰羔羊测定各组织器官重量,出生20、60 d采集羔羊血清测定血清抗氧化指标.结果表明:1)妊娠后期母羊饲粮营养水平对羔羊初生重、哺乳期(出生0～60 d)羔羊体重均无显著影响(P>0.05),但随营养水平降低,羔羊初生重有降低趋势(0.05≤P<0.10),出生40和50 d体重有增加趋势(0.05≤P<0.10).2)出生0d,随着妊娠后期母羊饲粮营养水平的降低,羔羊的胸深极显著提高(P<0.01),体斜长显著降低(P<0.05);出生60 d,随着妊娠后期母羊饲粮营养水平的降低,羔羊的胸深、曲冠臀长显著或极显著提高(P<0.05或P<0.01).3)出生10 d,羔羊的肝脏、肺脏的重量随妊娠后期母羊饲粮营养水平的降低而显著降低(P<0.05);出生60 d,各组羔羊的组织器官重量差异不显著(P>0.05).4)出生20和60 d,随着妊娠后期母羊饲粮营养水平的降低,羔羊血清中总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)活性、谷胱甘肽过氧化酶(GSH-Px)含量显著或极显著提高(P<0.05或P<0.01),丙二醛(MDA)含量极显著降低(P<0.01).妊娠后期通过精料补充料与饲草比例调控母羊饲粮营养水平时发现,低营养水平(低精料补充料比例)能够降低羔羊初生重,但经补偿生长作用,羔羊血清抗氧化能力得到提高,生长性能也得到恢复.     

Influence of dietary palm oil supplementation on serum lipid metabolites, carcass characteristics, and lipid composition of carcass tissues of growing ram and ewe lambs.

The objective of this research was to determine the influence of dietary palm oil supplementation on carcass characteristics and lipid composition of tissues from growing lambs. Twenty-eight Suffolk x Hampshire lambs were weaned at 60 d of age (average 36 kg BW) and assigned to a 2 x 2 factorial arrangement consisting of diet (control [NPO] or 10.6% added dietary palm oil [PO]) and sex (ram vs ewe). The NPO diet (77% forage and 23% concentrate) contained 11.2% CP and 2.66 Mcal of ME/kg. Palm oil replaced molasses in the PO diet. Lambs were individually given ad libitum access to feed for 60 d to a final BW average of 50.1 kg. Lipid composition of the longissimus muscle and corresponding subcutaneous (s.c.) adipose tissue was determined by gas-liquid chromatography (GLC). Lambs fed PO were fatter (P less than .01) than lambs fed NPO (.77 vs .56 cm, s.c. fat). Diet had no effect on cholesterol content of lean tissue; however, feeding PO increased the saturated fatty acids of lean tissue. The s.c. fat from lambs fed PO had less (P less than .01) cholesterol (64.79 vs 89.67 mg/100 g) and more saturated fatty acids than that from lambs fed NPO. Ewes were fatter (P less than .01) than rams, yet they had less cholesterol content in the s.c. adipose tissue (68.71 vs 85.74 mg/100 g). High amounts of dietary palm oil fed to growing lambs caused changes in fatty acid deposition and cholesterol metabolism and may be a useful investigative tool to study lipid metabolism in growing ruminants.(ABSTRACT TRUNCATED AT 250 WORDS)     

过瘤胃保护甜菜碱和过瘤胃保护胆碱对1～3月龄湖羊生长性能、消化性能、屠宰性能和脂肪沉积的影响

本试验旨在研究过瘤胃保护甜菜碱(RPB)和过瘤胃保护胆碱(RPC)对1~3月龄湖羊生长性能、消化性能、屠宰性能和脂肪沉积的影响。试验选用30只体重相近的1月龄左右的湖羊公羔,随机分成3组,分别为对照组、RPB组和RPC组,每组10只。对照组饲喂基础饲粮,RPB组和RPC组则饲喂在基础饲粮干物质(DM)基础上分别添加2.9 g/kg RPB和2.5 g/kg RPC的试验饲粮。预试期21 d,正试期54 d。结果表明:1)饲粮中添加RPB和RPC对1~3月龄湖羊的平均日增重、平均日采食量和料重比均无显著影响(P0.05),但RPB组、RPC组的平均日增重较对照组分别增加了19.97%和27.75%。2)饲粮中添加RPB和RPC对1~3月龄湖羊的粗蛋白质(CP)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)、DM和有机物(OM)的表观消化率均无显著影响(P0.05)。3)饲粮中添加RPB和RPC均可以显著降低1~3月龄湖羊的背膘厚(P0.05),对宰前活重、屠宰率、胴体重、GR值、眼肌面积、腹脂重、肾周脂肪重和肌内脂肪(IMF)含量无显著影响(P0.05),但RPB组和RPC组眼肌面积较对照组分别增加了10.86%和3.16%,IMF含量较对照组分别增加了17.27%和36.36%,肾周脂肪重较对照组分别降低了20.60%和22.67%。综合以上试验结果得出,饲粮中添加2.9 g/kg RPB或2.5 g/kg RPC均可以改善1~3月龄湖羊的脂肪沉积部位和胴体品质,并且从消化性能、生长性能和屠宰性能来看,在满足维持需要的饲粮营养水平下,2种添加剂的作用相当     

Effects of dietary conjugated linoleic acid on fatty acid composition, lipid oxidation, color, and water-holding capacity of pork loin

The effects of dietary conjugated linoleic acid (CLA) on fatty acid composition, lipid oxidation, and pork quality were investigated. Pigs (n = 20) were fed a diet containing 0, 1, 2.5, or 5% CLA for 4 wk and slaughtered at 105 kg. The longissimus thoracis et lumborum muscle was collected at 24 h postmortem. Pork loin chops (3 cm thick) were packaged aerobically and stored at 4 degrees C for 7 d. Samples were analyzed for ultimate pH, intramuscular fat content, fatty acid composition, thiobarbituric acid-reactive substances, color (L*, a*, b*), and water-holding capacity. Dietary CLA reduced the concentration of linoleic acid and increased CLA concentration in intramuscular fat of pork loin (P < 0.05). The concentration of CLA in muscle was increased with dietary CLA level and did not change during storage. Thiobarbituric acid-reactive substance value of control was higher than that of the CLA-fed groups (P < 0.05). Intramuscular fat content was increased by dietary CLA, and less purge loss was observed with samples from CLA-fed pigs (P < 0.05). Dietary CLA improved the color stability of pork loin during cold storage. After 7 d, lightness (L*) and yellowness (b*) of the 5% CLA-fed group were significantly lower than those of control (P < 0.05). The results indicated that the water-holding capacity of pork loin was increased with increased intramuscular fat content apparently caused by dietary CLA. Also, the data indicated that color stability of pork was improved with inhibition of lipid oxidation and changing of fatty acid composition by dietary CLA.