库布齐沙漠蒙古牛肉品质及肌肉矿物质元素含量分析

试验通过对库布齐蒙古牛与西门塔尔牛肉品质部分指标及肌肉矿物质含量进行分析测定,研究库布齐蒙古牛的肉品质特性。选择库布齐蒙古牛与西门塔尔牛各6头,采集背最长肌进行样品分析。结果表明:蒙古牛肉色泽深红,红度a^*、黄度b^*、系水率、熟肉率、剪切力均高于西门塔尔牛,且均呈显著性差异(P<0.05),而失水率及pH显著低于西门塔尔牛(P<0.05);蒙古牛肌肉微量元素Cr、Cu、Fe、Mn、Se、Zn含量均显著高于西门塔尔牛(P<0.05),肌肉中P和I含量均显著低于西门塔尔牛(P<0.05),其他元素含量差异不显著(P>0.05)。说明库布齐蒙古牛肉口感、多汁性及色度方面较优,肌肉中大部分矿物质元素含量高于西门塔尔牛,肉品质较高。     

运输后禁食与非禁食对肉兔应激水平、肉品质和行为的影响

本试验以伊拉肉兔为研究对象,探究肉兔运输后在禁食与非禁食条件下对其应激水平、肉品质和行为的影响,探索合理的肉兔运输后的处理方式。试验选取80只体重相近（（2.5±0.5） kg）的伊拉公兔,随机分为8个组：对照组、运输后0 h组、非禁食6 h组、非禁食24 h、禁食6 h组、禁食24 h组、禁食行为观察组和非禁食行为观察组（做行为观察,不屠宰）。预试期为7 d,正式期的运输时间为2 h。结果发现,在血清生化测定中,和对照组相比,运输后0 h组血清ALT、AST、TG、Glu、CK、LDH水平无显著变化（P>0.05）,而运输后0 h组血清TP浓度显著下降,皮质醇浓度显著上升（P<0.05）。非禁食24 h组血糖水平高于禁食24 h组（P<0.05）、血清CK浓度低于禁食24 h组（P<0.01）,非禁食6 h的LDH水平低于禁食6 h组（P<0.05）。在肉品质测定中,运输后0 h时肌肉pH显著上升（P<0.05）,肌肉L^*、a^*水平显著下降（P<0.05）,而非禁食24 h组的L^*、a^*和b^*值显著高于禁食24 h组。而禁食组与非禁食组的肌肉pH、失水率、蒸煮损失率和剪切力等无显著差异（P>0.05）。在基因表达方面,运输后0 h时JNK、Caspase-3的mRNA水平显著上升（P<0.05）。非禁食相比于禁食降低了JNK mRNA相对表达量（P<0.05）,对Caspase-3水平无显著影响（P>0.05）。在行为学方面,非禁食相比于禁食降低了肉兔的食粪行为（P<0.05）,对于肉兔刻板行为改变不明显（P>0.05）。本研究提示,在运输后静养期间,24 h非禁食能一定程度降低肉兔的应激、减少机体损伤、改善兔肉品质,有利于提高肉兔的福利水平。     

放牧与舍饲饲养方式对小尾寒羊肉品质的影响

本研究旨在探讨放牧和舍饲两种饲养方式对小尾寒羊肉品质的影响。将100只2月龄雄性断奶羔羊随机分为放牧组与舍饲组,至8月龄进行屠宰,比较两组羔羊肉的营养成分、氨基酸含量、肉色、pH、嫩度及产肉性能。结果表明,放牧组羊肉粗蛋白和水分含量显著高于舍饲组羊肉（P<0.05）。舍饲组羊肉干物质显著高于放牧羊肉（P<0.05）,粗脂肪极显著高于放牧组羊肉（P<0.01）。舍饲组羊肉蛋氨酸、天冬氨酸和丝氨酸含量显著高于放牧组羊肉（P<0.05）,苏氨酸、缬氨酸、异亮氨酸、亮氨酸、赖氨酸、谷氨酸和组氨酸含量均极显著高于放牧组羊肉（P<0.01）,必需氨基酸总量、非必需氨基酸总量和氨基酸总量也极显著高于放牧组羊肉（P<0.01）。放牧组羔羊背最长肌黄度值（b^*）和亮度值（L^*）极显著高于舍饲组（P<0.01）,肌纤维直径极显著低于舍饲组（P<0.01）,肌纤维密度极显著高于舍饲组（P<0.01）。舍饲组羊肉熟肉率极显著高于放牧组（P<0.01）,眼肌面积极显著大于放牧组（P<0.01）。综上所述,放牧饲养的羔羊其肉蛋白质含量较高,脂肪含量较低,肌纤维特性较好,舍饲饲养的羔羊其肉脂肪含量和氨基酸含量较高,肉色和产肉性能较好,生产中可结合两种饲养方式平衡养殖。     

北京黑猪MYH3和MYH13基因多态性与肉质性状的关联分析

【目的】 试验旨在研究肌球蛋白重链3（myosin heavy chain 3，MYH3）和肌球蛋白重链13（myosin heavy chain 13，MYH13）基因遗传变异对猪肉质性状的影响。【方法】 利用北京黑猪背最长肌样本进行肉质性状（肌内脂肪（intramuscular fat，IMF）、水分、滴水损失、酸碱度（pH）、肉色L^*值、肉色a^*值和肉色b^*值）表型数据的测定。利用PCR和Sanger测序技术对MYH3和MYH13基因启动子区和CDS区进行基因分型。将性别、场、日龄作为协变量，采用协方差分析，确定与猪肉质性状相关的SNPs，利用实时荧光定量PCR检测基因表达水平。【结果】 试验共筛选到9个SNPs，其中MYH3基因CDS区有1个错义突变（c.5782 G>C）与IMF显著相关（P<0.05），且MYH3基因表达水平与IMF呈正相关；MYH13基因CDS区有4个SNPs，其中2个（c.1923 G>A、c.1308 G>A）与肉色a^*值显著相关，1个（c.963 G>A）与滴水损失显著相关，1个（c.237 G>T）与肉色L^*值显著相关（P<0.05）；MYH13基因启动子区有4个SNPs，其中2个（rs699287502、rs318639161）与肉色L^*值显著相关，2个（rs321315318、rs330770991）与滴水损失显著相关（P<0.05），且MYH13基因表达水平与滴水损失呈负相关。【结论】 MYH3基因有1个SNP与IMF显著相关，且其基因表达水平与IMF呈正相关。MYH13基因中存在3个SNPs与滴水损失显著相关，且该基因启动子区2个SNPs基因表达水平与滴水损失呈负相关；3个SNPs与肉色L^*值显著相关；2个SNPs与肉色a^*值显著相关。以上SNPs均可作为影响北京黑猪肉质性状的候选基因功能位点。     

不同品种牛背最长肌抗氧化性能的研究

本试验旨在研究不同品种牛肌肉的抗氧化特性,为优质牛肉的生产提供试验数据。选用5个品种牛(利木赞牛、中国西门塔尔牛、鲁西牛、秦川牛、晋南牛)的背最长肌,测定肌内脂肪含量、24小时的滴水损失以及在0～4℃下肉色、过氧化物值(PV)及硫代巴比妥酸反应物(TBARS)在72h内的变化动态。结果表明,背最长肌的肌内脂肪含量与24小时滴水损失率在不同品种牛肌肉之间没有显著差异(P>0.05);在整个储存时期(0～72h),5个品种牛肌肉的a*、b*值均呈下降趋势;4～72h内,利木赞牛肌肉的a*值均是最高的,且在冷藏8、12h时,利木赞牛肌肉的a*值显著大于鲁西牛肉和秦川牛(P<0.05),24h后利木赞牛的a*值显著大于西门塔尔牛(P<0.05);随着储存时间的延长,5个品种牛背最长肌的PV和TBARS值均有不同程度的增加,利木赞牛肌肉的PV和TBARS值增加最慢,秦川牛和鲁西牛肌肉的PV和TBARS值增加较快。结果表明,5个品种牛的肌内脂肪含量和滴水损失差异不显著,利木赞牛肌肉能够较长时间保持肉色和抗氧化特性。     

Effects of Different Ammonia Concentrations on Growth Performance,Immunity and Antioxidant Capacity of Beef Cattle

The aim of this study was to investigate the effects of different ammonia concentration on production performance, immunity and antioxidant capacity of beef cattle. In this study, 16 healthy Qinchuan cows with an initial weight of (220±5) kg were randomly divided into 4 groups with 4 replicates per group and 1 cattle per replicate.Treated with ammonia at concentrations of<5 (control), (15±3), (30±3) and (45±3) mg·m^-3, respectively. The advanced experiment period was 10 days and the formal period was 30 days. During the trial period, the production performance was recorded(ADG,ADFI and F/G), and serum samples were collected from the jugular vein at day 1, 15, 30. Then the biochemical indicators, immune globulin,cytokines and antioxidant enzymes activities were measured.The results showed as follows:1) Compared with the control group, average daily gain (ADG) significantly decreased when ammonia concentration was 30 mg·m^-3, and average daily feed intake (ADFI) was significantly decreased in all ammonia treatment groups (P<0.05), and feed∶gain (F/G) increased significantly when ammonia concentration was 15 and 30 mg· m^-3 (P<0.05). 2) The content of serum CRE、BUN、ALT、AST and LDH were significantly increased when the ammonia concentration was 45 mg·m^-3 (P<0.05), and the An content increased significantly in all ammonia treatment groups compared with the control group, indicating that ammonia exposure caused damage to liver and kidney function of cattle. 3) The immunoglobulin A (IgA) level was significantly reduced in each ammonia treatment group (P<0.05), the content of IgM was significantly decreased when the ammonia concentration was 30 and 45 mg· m^-3 (P<0.05). However, there was no significant difference in IgG content among the groups (P>0.05). Ammonia exposure significantly increased the levels of IL-6 at 30 and 45 mg·m^-3, and IL-4 content was significantly increased at 45 mg· m^-3 (P<0.05), IFN-γ content was significantly reduced at 30 and 45 mg· m^-3 (P<0.05), thus inducing an inflammatory response of beef cattle. 4) Ammonia exposure significantly decreased T-AOC activity at 30 and 45 mg· m^-3 and GSH-Px activity was significantly decreased at 45 mg· m^-3 (P<0.05), MDA content significantly increased at 30 mg· m^-3 (P<0.05);No significant difference was observed in the serum SOD and CAT activities in each group (P>0.05). In summary, this study suggested that excessive ammonia exposure reduced growth performance, impaired immunity and antioxidant capacity of beef cattle.     

不同氨气浓度对肉牛生产性能、免疫和抗氧化能力的影响

本试验旨在研究不同氨气浓度对肉牛生产性能、免疫和抗氧化能力的影响。选取16头初始体重为（220±5）kg的健康秦川母牛,随机分为4组饲养于4个环控舱内,每组4个重复,每头牛为1个重复。将氨气浓度分别设置为<5（对照组）、（15±3）、（30±3）和（45±3）mg·m^-3。预试期为10 d,试验期为30 d。试验期间记录生产性能（日增重、日采食量和料重比）,并于试验第1、15和30天颈静脉采集血清样本,检测肉牛血液生化指标、免疫球蛋白、细胞因子和抗氧化酶活性。结果表明：1）与对照组相比,氨气浓度为30 mg·m^-3时显著降低了肉牛平均日增重（ADG）,平均日采食量（ADFI）在所有氨气处理组均显著下降（P<0.05）,而料重比（F/G）在氨气浓度为15和30 mg·m^-3时显著上升（P<0.05）。2）氨气浓度达到45 mg·m^-3时显著增加了血清肌酐、尿素氮、谷丙转氨酶、谷草转氨酶和乳酸脱氢酶含量（P<0.05）,而与对照组相比,血氨含量在所有处理组均显著增加,表明氨气暴露对肉牛的肝、肾功能造成了损伤。3）各氨气处理组均显著降低了免疫球蛋白A含量（P<0.05）,而免疫球蛋白M含量在氨气浓度为30和45 mg·m^-3时显著下降（P<0.05）,但免疫球蛋白G含量在各组间无显著差异（P>0.05）,白细胞介素6含量在氨气浓度为30和45 mg·m^-3时显著上升,而白细胞介素4含量在45 mg·m^-3时显著上升（P<0.05）,γ-干扰素含量在氨气浓度为30和45 mg·m^-3时显著降低（P<0.05）,表明氨气暴露引发了肉牛的炎症反应。4）氨气浓度在30和45 mg·m^-3时显著降低了血清总抗氧化能力,在45 mg· m^-3时显著降低了谷胱甘肽过氧化物酶活性（P<0.05）,丙二醛含量在30 mg·m^-3时显著增加（P<0.05）;但血清超氧化物歧化酶和过氧化氢酶活性在各处理组间无明显差异（P>0.05）。综上所述,过量氨气暴露降低了肉牛的生长性能,并对肉牛的免疫和抗氧化能力产生了不利影响。     

肉用西门塔尔牛与和牛杂交群体的肉品质分析

本研究旨在对肉用西门塔尔牛与杂交和牛两试验群体进行肉质性状比较,以期为肉品质性状遗传机制剖析及优质肉牛培育提供理论指导。收集肉用西门塔尔牛与杂交和牛两试验群体肉质性状表型数据,包括眼肌面积、剪切力、系水力、pH、肉色、脂肪颜色和大理石花纹等指标,进行相关性及差异性分析,从而综合评价两群体的肉品质。结果显示,两群体的脂肪颜色、系水力及剪切力呈现两两正相关;肉色与脂肪颜色、pH呈正相关,且肉色与pH呈显著相关（P < 0.05）,而系水力与pH、肉色和大理石花纹呈负相关。在两试验群体间,和牛杂交群体的大理石花纹、眼肌面积、pH性状表现为极显著优于肉用西门塔尔牛（P < 0.01）。从性别比较来看,肉用西门塔尔牛母牛在大理石花纹、pH、剪切力等性状上极显著或显著优于公牛（P < 0.01;P < 0.05）;而和牛杂交群体母牛的肉色和剪切力性状表现为显著或极显著高于公牛（P < 0.05;P < 0.01）。总体而言,和牛杂交群体的肉质性能优于肉用西门塔尔牛;群体内比较表明,肉用西门塔尔牛群体母牛肉质性能优于公牛,而和牛杂交群体母牛肉质性能低于公牛。     

冷季不同饲养模式对牦牛肉品质的影响

旨在研究冷季自然放牧与育肥的饲养模式对牦牛肉品质、营养品质的影响。为评价冷季短期育肥营养调控牦牛肉品质提供理论和数据参考。本研究选择体重相近（（270±10）kg）,健康无疾病的5周岁公牦牛共12头,随机分为放牧与舍饲育肥组,每组6个重复,每个重复1头牛。同时进行传统全放牧饲养与全混合日粮（total mixed rations,TMR）舍饲饲养,试验周期120 d。育肥试验结束后对两组牦牛进行屠宰,并分别采集其背最长肌（longissimus dorsi,LD）、肱二头肌（biceps brachii,BB）、股二头肌（biceps femoris,BF）各500 g,用于测定肌肉肉品质（加工品质、食用品质）及营养成分。结果表明：1）经舍饲育肥后,牦牛3个部位肉色亮度值（L^*）均有显著提高（P<0.05）,但红度值（a^*）显著降低（P<0.05）。LD失水率显著降低（P<0.05）;BB以及BF失水率极显著降低（P<0.01）;LD的蒸煮损失和剪切力极显著降低（P<0.01）;BB和BF的蒸煮损失和剪切力显著降低（P<0.05）。2）舍饲育肥对不同部位牦牛肌肉中水分、蛋白质、脂肪、钙和磷的含量均存在极显著影响（P<0.01）,但灰分含量仅在LD中存在极显著影响（P<0.01）。3）舍饲育肥对LD的必需氨基酸（essential amino acids,EAA）和非必需氨基酸（non-essential amino acids,NEAA）含量都存在显著影响（P<0.05）,其余两个部位则影响不大（P>0.05）,在3个部位的肌肉中,脂肪酸都为以C_16：0、C_18：0、C_18：1N₉C、C_18：2N₆C和C_20：4N₆为主,极显著降低了各部位肌肉的多不饱和脂肪酸（polyunsaturated fatty acid,PUFA）含量（P<0.01）,极显著提高了单不饱和脂肪酸（monounsaturated fatty acid,MUFA）的含量（P<0.01）,并降低了各部位n-6/n-3的比值。结果提示,与传统放牧相比,冷季育肥的饲养模式对于牦牛肉亮度和红度有一定影响,提高了牦牛肉的加工品质,降低了蒸煮损失,同时一般营养价值也高于放牧牦牛。育肥牦牛背最长肌氨基酸组成优于放牧牦牛,蛋白质品质更好,虽然育肥损失了一些肌肉中丰富、健康的脂肪酸,但提高了脂肪含量,对于牦牛肉的食用品质和嫩度有了很大改善。     

Study on Supplementary Quantity of Grazing Beef Cattle in Spring in Inner Mongolia Grassland

The experiment was conducted to study the optimal supplementary feeding quantity of grazing beef cattle in spring in Inner Mongolia grassland.Seventy-five Simmental beef cattle with average weight of (281.19±17.15)kg were selected and divided into 5 groups (group A,B,C,D and E) with 15 replicates per group.Those cattle grazed optionally and supplemented with 0,0.8,1.7,2.5,3.4 kg/d concentrate,respectively,according to beef cattle weight of 0,0.3%,0.6%,0.9% and 1.2%.Pre-trial period was 15 d,the trial period was 60 d.The results showed that,with the increasing of concentrate supplementation,the daily gain of beef cattle was gradually significant increased (P < 0.05);Group D were 331.25%,130.00% and 38.00% higher than that of group A,B and C,respectively,the apparent digestibility of dry matter and crude protein were significantly higher than that of other groups (P < 0.05).The daily income of group D was 11.22 yuan and were 183.33%,102.53%,36.17%,20.52% significantly higher than that of group A,B,C and E (P < 0.05),the fattening income of group D was the highest.According to above results,the optimum adding levels was 2.5 kg/d in spring under the condition of grazing in Inner Mongolia.The higher daily gain and higher economic benefits could be obtained under the optimal supplementary feeding quantity.     

内蒙古草原放牧肉牛春季补饲量的研究

试验旨在研究内蒙古草原放牧肉牛春季最佳补饲量。选择75头体重为(281.19±17.15)kg的健康西门塔尔杂交肉牛随机分为5组(A、B、C、D、E组),每组15头牛,1头牛为1个重复。各组分别按体重的0、0.3%、0.6%、0.9%及1.2%补饲精料,依次为0、0.8、1.7、2.5及3.4 kg/d,其他放牧条件相同。预试期15 d,正试期60 d。结果表明,随着精料补饲量的增加,肉牛的平均日增重依次显著增加(P < 0.05),D组平均日增重较A、B、C组分别提高331.25%、130.00%及38.00%,日粮中干物质和粗蛋白质的表观消化率显著高于其他各组(P < 0.05);D组日均收入为11.22元,分别较A、B、C及E组显著提高了183.33%、102.53%、36.17%及20.52%(P < 0.05),育肥效益最好。综合以上结果,内蒙古草原春季放牧条件下,肉牛每天的最佳补饲量为2.5 kg,在此条件下可获得较高的日增重及较高的经济收益。     

Comparative Study on Carcass Traits and Meat Quality of Different Month Old of Xinjiang Brown Cattle Steers

In this research,12 heads of 28 to 30 months (low months age group) and 8 heads of 32 to 34 months (high months age group) Xinjiang Brown cattle steers which fed in the same mode of nutrition were chose for the slaughter test,in which the carcass traits,nutrient composition and some edible quality index were measured and comparative analyzed,a research which through comparative analysis the carcass traits and meat quality of nutritional components of different months of Xinjiang Brown cattle steers was carried out.The results indicated that the marbling,carcass grade,fat,meat color of high months age group were better than that of low months age group,the traits of the low months age group on fat color,moisture,protein,cooking loss and shear force value were better than that of high months age group,and there were significant difference on the traits of fat and meat color L^* between the two groups (P<0.05),while the differences of other traits between them were not significant (P>0.05);As high-grade beef,in addition to the traits of meat color and pH value of the chunk roll,tenderloin and striploin,each site of the meat traits on the fat,protein,moisture,cooking loss,shear force value indicators were all better than other parts,and showed the best of nutritional value and edible quality.28 to 34 months of Xinjiang Brown cattle steers could produce high-grade beef,the meat could be used as the raw materials of steak and boiled beef.     

不同月龄新疆褐牛阉牛胴体性状及肉品质比较研究

选择相同营养模式下低月龄组(28~30月龄)12头、高月龄组(32~34月龄)8头新疆褐牛阉牛进行屠宰,分别对胴体性状、营养成分、部分食用品质指标进行测定和比较分析,旨在探索新疆褐牛阉牛生产高档牛肉的适宜月龄。结果表明,高月龄组大理石花纹、胴体等级、脂肪、肉色均优于低月龄组,低月龄组脂肪色泽、水分、蛋白质、蒸煮损失、剪切力值优于高月龄组,且脂肪、肉色L^*值差异显著(P<0.05),其余组间差异均不显著(P>0.05);上脑、里脊、外脊作为高档牛肉,除肉色、pH外,脂肪、蛋白质、水分、蒸煮损失、剪切力值指标均优于其他部位,表现出了极好的营养价值和食用品质。28~34月龄阶段的新疆褐牛阉牛可以生产高档牛肉,其肉品都可作为牛排和涮牛肉的原材料。     

Effect of Soybean Meal Replaced by Fermented Rapeseed Meal on Growth Performance,Meat Quality and Serum Biochemical Indexes of Broilers

This experiment was conducted to study the effect of soybean meal replacement by fermented rapeseed meal on growth performance,meat quality and serum biochemical indexes of broilers.A total 400 23-day-old Yellow-feathered male broilers were randomly divided into 4 groups with 4 replicates per group and 25 broilers per replicate.The broilers in control group were fed a basal diet,and the others were fed the basal diets with the 3% (group Ⅰ),6% (group Ⅱ) and 9% (group Ⅲ) fermented rapeseed meal equal-nutritionally replacing the soybean meal,respectively.The experiment lasted for 43 days.The results showed as follows:① Compared with control group,the ADG,ADFI and F/G of groups Ⅰ,Ⅱ and Ⅲ showed no significant differences (P>0.05);The ADG of group Ⅲ were 16.47% (P<0.05),15.03% (P<0.05) higher than that of groups Ⅰ and Ⅱ,the F/G of group Ⅲ were 7.71% (P<0.05),4.27% (P>0.05) lower than that of groups Ⅰ and Ⅱ.② There were no significant differences in the pH₁,pH₂₄,meat color (L^*,a^*,b^*),cooking loss and tenderness of chest muscle among all groups(P>0.05);Compared with control group,the water loss rate of groups Ⅰ,Ⅱ and Ⅲ were significantly decreased (P<0.05).③ Compared with control group,the serum GLU content of groups Ⅰ,Ⅱ and Ⅲ were decreased by 13.06%(P<0.05),8.12%(P>0.05) and 9.57%(P>0.05);The serum TP content of groups Ⅰ,Ⅱ and Ⅲ were increased by 2.50%(P>0.05),20.86%(P<0.05) and 33.92%(P<0.05);The serum GPT content of groups Ⅰ,Ⅱ and Ⅲ were decreased by 7.99%(P>0.05),18.85%(P>0.05) and 26.98%(P<0.05).It was concluded that it would be feasible to replace the soybean meal with 3% to 9% fermented rapeseed meal in broiler feeding,and the optimum supplemental level of fermented rapeseed meal was 9%.     

发酵菜籽粕替代豆粕对肉鸡生长性能、肉品质及血清生化指标的影响

本试验旨在研究发酵菜籽粕替代豆粕对肉鸡生长性能、肉品质及血清生化指标的影响。选用23日龄黄羽肉公鸡400只,随机分为4组,每组4个重复,每个重复25只,对照组饲喂基础日粮,试验Ⅰ、Ⅱ和Ⅲ组分别在基础日粮中添加3%、6%和9%发酵菜籽粕等营养替代豆粕。试验期43 d。结果表明:①与对照组相比,试验Ⅰ、Ⅱ和Ⅲ组肉鸡平均日增重、平均日采食量和料重比差异均不显著(P>0.05);与试验Ⅰ、Ⅱ组相比,试验Ⅲ组肉鸡平均日增重分别提高16.47%(P<0.05)、15.03%(P<0.05),料重比分别降低7.71%(P<0.05)和4.27%(P>0.05)。②各组肉鸡胸肌的pH₁、pH₂₄、肉色(L^*、a^*、b^*)、蒸煮损失和嫩度差异均不显著(P>0.05);试验Ⅰ、Ⅱ和Ⅲ组肉鸡胸肌的失水率与对照组相比均显著降低(P<0.05)。③与对照组相比,试验Ⅰ、Ⅱ和Ⅲ组肉鸡血清中葡萄糖含量分别降低13.06%(P<0.05)、8.12%(P>0.05)和9.57%(P>0.05);总蛋白含量分别提高2.50%(P>0.05)、20.86%(P<0.05)和33.92%(P<0.05);谷丙转氨酶含量分别降低7.99%(P>0.05)、18.85%(P>0.05)和26.98%(P<0.05)。综上所述,肉鸡日粮中添加3%~9%发酵菜籽粕等营养替代豆粕是可行的,其中添加9%发酵菜籽粕效果最好。     

鲁西牛不同杂交组合生产性能比较分析

试验旨在探索鲁西黄牛与不同优良肉牛品种的杂交效果，提高鲁西黄牛的生产性能。选取111头健康公牛分为4组：A组为29头利木赞牛×鲁西牛杂交牛（利鲁牛）；B组为26头西门塔尔牛×鲁西牛杂交牛（西鲁牛）；C组为27头和牛×鲁西牛杂交牛（和鲁牛）；D组为29头纯种鲁西牛。在相同饲养管理条件下进行育肥及屠宰试验，并对育肥效果进行综合分析。结果显示，利木赞牛、西门塔尔牛、和牛对鲁西牛均有较好的杂交改良效果；平均日增重以西鲁牛最高，极显著高于其他3组牛（P<0.01）；宰前活重、胴体重、屠宰率均以西鲁牛最高，显著高于其他3组牛（P<0.05）；和鲁牛大理石花纹沉积能力最强；日平均采食量和日平均饲料成本在各组间差异均不显著（P>0.05）。综合分析，从产肉量来讲，西鲁牛最佳；从大理石花纹沉积能力来讲，和鲁牛最佳。     

The Quality Evaluation of Different Anatomical Locations of Yunling Cattle

In order to define the quality characteristics of different anatomical locations of Yunling cattle,the pressing loss rate,cooking loss rate,shear force,pH, L^* value,a^* value,b^* value,crude protein content,crude fat content and moisture of supraspinatus (SU),infraspinatus (IF),triceps brachii (TB),rhomboideus (RH),serratus ventraliscervicis (SVC),splenius (SP),psoas major (PM),longissimus dorsi (LD),latissimus dorsi (LA),semimembranosus (SM),semitendinosus (ST),biceps femoris (BF),gluteus medius (GM),rectusfemoris (RF),vastus lateralis (VL), tensor fasciae latae (TFL) from Yunling cattle carcass were determined.The quality traits of Yunling cattle meat among different anatomical locations were analyzed using variance,correlation and standardization analysis. The result showed that there were significant differences in quality traits among various anatomical locations (P<0.05). The SU,IF,PM,SVC and TFL had higher tenderness comparing to other muscles with shear force values less than 4 kg,while the water holding capacity of SP,ST and VL was poorer than other muscles. The ST had the highest L^* value among all muscles. There was significantly positive correlation between shear force and pressing loss, cooking loss rate. The LD and ST had similar quality characteristic,while BF,GM and VL had similar quality characteristic. It was showed that different parts of muscle had significant effect on Yunling cattle meat quality.The quality of forequarter meat was better, which could be used to develop high-end products.     

云岭牛不同解剖部位肉品质评价

为了明确云岭牛不同解剖部位肉的品质特性,本试验测定了云岭牛冈上肌（SU）、冈下肌（IF）、臀三头肌（TB）、菱形肌（RH）、颈腹侧锯肌（SVC）、夹肌（SP）,中部胴体的腰大肌（PM）、背最长肌（LD）、背阔肌（LA）,后部胴体的半膜肌（SM）、半腱肌（ST）、股二头肌（BF）、臀中肌（GM）、股直肌（RF）、股外侧肌（VL）和阔筋膜张肌（TFL）共16个解剖部位肉的压力失水率、蒸煮损失、剪切力、pH、亮度（L^*）、红度（a^*）、黄度（b^*）、粗蛋白质、脂肪、水分10项品质指标,并通过方差分析、相关性分析和标准化分析研究其品质特性。结果显示,云岭牛不同解剖部位肉之间的10项品质指标均存在显著差异（P<0.05）。冈上肌、冈下肌、腰大肌、颈腹侧锯肌和阔筋膜张肌的嫩度较好,其剪切力均低于4 kg。夹肌、半腱肌和股外侧肌的保水性较差,半腱肌的L^*值最高。相关性分析结果表明,剪切力和压力失水率、蒸煮损失呈显著正相关。标准化分析发现,背最长肌和半腱肌具有相似的品质特征;股二头肌、臀中肌和股外侧肌具有相似的品质特征。结果表明,部位因素对云岭牛肉品质具有显著影响,云岭牛胴体前部肉品质较好,可以作为开发高档产品的原料来源。     

枸杞渣和甘草混合添加剂对黄羽肉鸡生产性能和肉品质的影响

试验旨在研究在日粮中添加枸杞渣和甘草混合添加剂（LWRMA）对黄羽肉鸡生产性能和肉品质的影响。将240只健康的1日龄良凤花黄羽肉鸡（公母各半）按体重相近的原则随机分成4组,每组6个重复,每个重复10只鸡。对照组（CS）饲喂在基础日粮中添加45 mg/kg金霉素的日粮,试验Ⅰ、Ⅱ、Ⅲ组分别饲喂在基础日粮中添加1%、2%、4% LWRMA的日粮。试验期为56 d。结果显示：①与对照组相比,试验Ⅲ组的平均日采食量（ADFI）显著提高（P<0.05）;平均日采食量与LWRMA添加量在多个试验阶段（1~14、29~41、42~56、1~28、29~56、1~56 d）都呈显著线性效应（P<0.05）;各组间平均日增重（ADG）和料重比（F/G）均无显著差异（P>0.05）。②与对照组相比,试验Ⅲ组的胸肌率显著提高（P<0.05）;胸肌率与LWRMA添加量存在显著线性效应（P<0.05）;试验Ⅱ、Ⅲ组胸肌和腿肌的黄度（b^*）极显著提高（P<0.01）,试验Ⅲ组的腿肌剪切力显著降低（P<0.05）;肌肉黄度、胸肌的红度（a^*）及系水力、腿肌剪切力均与LWRMA添加量存在显著的线性效应（P<0.05）,平均肌纤维横截面积和平均肌纤维密度均与LWRMA添加量呈显著线性效应（P<0.05）。③LWRMA添加水平对各组胸肌T-AOC、CAT、SOD和GSH-Px活性没有显著影响（P>0.05）。综上所述,黄羽肉鸡日粮中添加4% LWRMA不仅在生产性能及肌肉抗氧化性能方面可获得与添加金霉素同样的效果,而且可改善肉品质。