集约化饲养模式下巴美肉羊与小尾寒羊产肉性能的比较研究

为研究集约化饲养模式下巴美肉羊与小尾寒羊的生长性能、屠宰性能及肉品质指标,试验选择4月龄体况良好、体重相近的巴美肉羊和小尾寒羊公羔各10只,按品种分为2组,饲喂以精粗质量比为50∶50(干物质基础)的全混合日粮(TMR)。测定各试验羊饲养120d期间的相关生长性能指标和相关屠宰性能及肉品质指标。结果表明:1)巴美肉羊的干物质采食量、试验末体重、总增重和日增重均极显著高于小尾寒羊(P0.01);2)巴美肉羊宰前活重(P0.01)、热胴体重(P0.05)和眼肌面积(P0.05)均显著高于小尾寒羊,而屠宰率则显著低于小尾寒羊(P0.01);3)巴美肉羊背最长肌宰后45min的pH(P0.05)、宰后1h的红色度(a*)和黄色度(b*)(P0.01)以及宰后24h的红色度(a*)(P0.05)等指标均显著高于小尾寒羊,而巴美肉羊背最长肌的剪切力、滴水损失和蒸煮损失等指标显著低于小尾寒羊(P0.05)。由此可见,在以TMR日粮为主要饲喂方式的集约化饲养模式下,巴美肉羊比小尾寒羊能发挥更高的生产性能并生产出品质更佳的羊肉。     

不同精粗比全混合日粮对育肥羔羊屠宰性能及肉品质的影响

以南非肉用美利奴羊为父本,东北细毛羊为母本进行杂交,选取出生日期相近的4月龄断奶公羔F1代12只,随机分成A组和B组,每组6只,A组和B组分别饲喂精粗比6∶4和8∶2饲粮,研究不同饲粮对杂交一代羔羊屠宰性能及肉品质性状的影响。结果表明,B组宰前活重、胴体重、净肉重、骨重和板油重显著提高(P0.05);A组的失水率显著高于B组(P0.05);在羊肉的营养成分中,羊肉的干物质含量A组显著低于B组(P0.05),粗蛋白B组极显著高于A组(P0.01);粗脂肪A组极显著高于B组(P0.01);脂肪酸含量方面,不饱和脂肪酸亚油酸、亚麻酸和油酸的含量B组极显著高于A组(P0.01),饱和脂肪酸硬脂酸和棕榈酸的含量B组极显著低于A组(P0.01),从食品营养学的角度来讲,B组羊肉对人体有利。     

饲养方式对猪宰前生理行为、胴体性质及肉品质的影响

【目的】在两种饲养方式下,对猪运输前后唾液皮质醇水平、待宰栏行为和宰时血液福利指标作对比分析,以期说明发酵床饲养可降低猪对宰前应激的生理反应,最后对胴体性质和肉品质进行评估。【方法】按照密度一致原则(0.85 m~2/头),将144头日龄相近(70.47±1.60 d)体重为(27.08±1.06)kg的杜长大三元仔猪(公母各半)随机分为两组,即水泥地面饲养组(concrete floor house,CFH)和发酵床饲养组(deep-litter house,DLH),每组6次重复,CFH和DLH中每个重复分别为10和14头,自由采食和饮水。饲养期间记录猪日采食量,分别于试验第64和106天进行个体称重,按重复计算平均日增重和料肉比;试验结束时,每组选择10头体重约为105 kg猪进行屠宰(公母各半)。于运输前即饲喂栏(-60 min)和运输后待宰栏内0和120 min采集猪唾液,用于皮质醇测定;待宰栏内采集行为录像,用于猪行为学分析;宰时采集血液用于葡萄糖、乳酸、皮质醇含量及肌酸激酶活性测定;最后对猪胴体性质(热胴体重、屠宰率、胴体滴水损失、背膘厚、肉厚、瘦肉率)和背最长肌肉品质(p H、肉色、肌内脂肪、滴水损失、剪切力)进行评价。【结果】1饲养期间,CFH和DLH猪末重、日均采食量、日增重及料肉比均无显著差异(P0.10)。2运输前后,DLH猪唾液皮质醇水平均高于CFH猪(P0.05);与运输前相比(-60 min),运输后0和120 min DLH猪唾液皮质醇升幅均显著低于CFH猪(0 min:+2.85±0.66 vs.+5.08±1.33,P0.01;120 min:+1.03±0.63 vs.+2.66±1.54,P=0.04)。3待宰栏休息时,在0-30 min和30-60 min时段,猪休息、站立、探究、走动、争斗和饮水等行为方面,CFH和DLH组之间无显著差异(P0.10);然而,在60-90min时段时,DLH猪在探究、走动、争斗等行为方面显著低于CFH猪(P0.05)。4与CFH相比,DLH显著降低了宰时猪血液中乳酸含量和肌酸激酶活性(P0.01),对皮质醇含量有增加趋势(P=0.07),但对葡萄糖含量无显著影响(P0.10)。5 CFH和DLH猪屠宰率、胴体滴水损失、平均背膘厚及肉厚均无显著差异(P0.10);关于肉品质,与CFH比,DLH对猪背最长肌肌内脂肪含量和滴水损失分别有提高和降低趋势(P=0.10),但对p H、L*(亮度)、a*(红度)、b*(黄度)等指标无显著影响(P0.10)。【结论】DLH能够降低待宰栏内猪的争斗行为和宰前生理应激反应,提高猪对宰前应激的应对能力,但对其生长性能、胴体性质和肉品质无显著影响。     

Impact of Adrenaline or Cortisol Injection on Meat Quality Development of Merino Hoggets

Increased levels of stress hormones in the muscle could lead to post mortem metabolic/structural modiifcations that could be relfected on meat quality. The present study investigated the metabolic effect of either adrenaline or cortisol injected into lambs in order to obtain an animal model of acute stress. Results showed that adrenaline or cortisol injection lead to glucose metabolism and muscle temperature increase. Muscle pH immediately post mortem was affected by adrenaline treatment. Water holding capacity （WHC） of fresh muscle, ifnal muscle pH and temperature registered at 24 h post mortem were not affected by injected hormones. Hardness and adhesiveness of LD muscle evaluated 3 d post mortem tended to increase as a result of adrenaline or cortisol injection. Results demonstrated that injected hormones were able to affect the post mortem muscle biochemistry and the pH/T curve independently of ifnal muscle pH.     

Epigenome-wide DNA methylation analysis reveals differentially methylation patterns in skeletal muscle between Chinese Chenghua and Qingyu pigs

Chenghua (CH) pig and Qingyu (QY) pig are typical Chinese native fatty breeds. CH pig is mainly distributed in Chengdu Plain, while QY pig is widely distributed throughout the mountain areas around the Sichuan Basin. There are significant differences in their phenotypic traits, including body image, growth performance, and meat quality. This study compared several meat quality traits of CH and QY pigs and conducted a genome-wide DNA methylation analysis using reduced representation bisulfite sequencing (RRBS). It was observed that the pH at 45 min (pH_45min, P=5.22e–13), lightness at 45 min (L*_45min, P=4.85e–5), and lightness at 24 h (L*_24h, P=3.57e–5) of CH pigs were higher than those of QY pigs. We detected 10 699 differentially methylated cytosines (DMCs) and 2 760 differentially methylated genes (DMGs) associated with these DMCs. Functional analysis showed that these DMGs were mainly enriched in the AMPK signaling pathway, Type II diabetes mellitus, Insulin signaling pathway, mTOR signaling pathway, and Insulin resistance. Furthermore, 15 DMGs were associated with fat metabolism (ACACA, CAB39, CRADD, CRTC2, FASN, and GCK), muscle development (HK2, IKBKB, MTOR, PIK3CD, PPARGC1A, and RPTOR), or meat quality traits (PCK1, PRKAG2, and SLC2A4). The findings may help to understand further the epigenetic regulation mechanisms of meat quality traits in pigs and provide new basic data for the study of local pigs.     

济宁青山羊羔羊初生重、死亡率及其影响因素分析

为分析济宁青山羊初生重和死亡率2个重要经济性状的影响因素,利用SPSS 19.0和SAS 9.2软件对这2个指标进行描述性统计、最小二乘方差分析和协方差分析,分析2012—2017年产羔记录中出生年份、出生季节、配种季节、性别和产羔类型5个因素对济宁青山羊羔羊初生重和死亡率的影响并求得羔羊初生重、死亡率的最小二乘均值。结果表明：1)出生年份、出生季节、性别和产羔类型对羔羊初生重均有极显著的影响(P<0.01);产羔类型对羔羊死亡率有显著影响(P<0.05)、配种季节对羔羊死亡率有极显著影响(P<0.01)。2)2012—2017年6年羔羊初生重呈先下降后增加再下降的趋势,死亡率呈先下降再增加的趋势。3)公羔初生重极显著高于母羔初生重(P<0.01)。4)随着母羊产羔数的增加,死亡率升高。单羔的初生重极显著高于四羔及以上(P<0.01),双羔的初生重与三羔差异显著(P<0.05)。5)秋季出生的羔羊初生重极显著高于其他季节。春季所产羔羊的初生重显著高于夏季和冬季(P<0.05)。综上,济宁青山羊初生重和死亡率受出生年份、出生季节、配种季节、性别和...     

不同铜源和水平对肥育绵羊胴体性状、肉品质和脂肪酸组成的影响

为改善和提高绵羊肉的品质,研究不同铜源和水平对肥育绵羊胴体性状、肉品质和脂肪酸组成的影响,本试验选用50只体重相近((23.8±1.6)kg)、3月龄左右的杜泊×蒙古羊杂交一代羯羊,随机分为5组,分别饲喂5种日粮:1)基础日粮(不加铜);2)基础日粮+10 mg/kg(DM)赖氨酸铜;3)基础日粮+20 mg/kg(DM)赖氨酸铜;4)基础日粮+10 mg/kg(DM)碱式氯化铜;5)基础日粮+20 mg/kg(DM)碱式氯化铜.结果表明,日粮中添加铜显著降低了肥育绵羊背膘厚和肾脂率(P<0.01),但对热胴体重、屠宰率和眼肌面积影响差异不显著(P>0.05);日粮中添加铜对肥育绵羊肉品质没有影响(P>0.05),对血浆、肌肉和脂肪组织中脂肪酸组成也无影响(P>0.05).赖氨酸铜和碱式氯化铜2种铜源以及10和20 mg/kg(DM)2种铜水平对肥育绵羊胴体性状、肉品质和脂肪酸组成的影响是相同的,因此,本研究建议绵羊日粮的适宜铜源为碱式氯化铜,适宜铜水平为16.74 mg/kg(DM).     

饲喂全价颗粒饲料对子午岭黑山羊生产性能的影响

为建立羔羊短期最佳经济育肥饲养模式,以子午岭黑山羊羔羊作为研究对象,采用全价颗粒饲料(试验组)和当地配合饲料(对照组)进行短期育肥试验,观测其生长性能、屠宰性能和肉品质。生长结果表明:试验组羔羊的生长性能、胴体重和屠宰性能均高于对照组(P0.05),试验组和对照组的育肥期增重分别是5.15 kg和4.51 kg,胴体重分别是10.54 kg和9.88 kg,屠宰率分别是49.63%和48.31%。肉品质测定结果表明:试验组的部分肉品质优于对照组,试验组的失水率比对照组低5.4%(P0.01),熟肉率比对照组高8.15%(P0.01)。经济效益分析结果表明:试验组每只羔羊的纯收益较对照组高16元。由此说明,用全价颗粒饲料短期育肥子午岭黑山羊羔羊的效果较优。     

不同宰前禁食时间对羊肉品质影响的研究

【目的】动物在装卸和运输过程中的断料断水以及宰前休息期人为控制的禁食禁水行为称为宰前禁食。不当的宰前禁食处理可能降低畜禽胴体出品率,对肉的食用品质和加工性能产生不良影响。研究不同宰前禁食时间处理对羊肉品质的影响,确定适宜于肉羊的宰前禁食时间,对生产优质羊肉有重要意义。【方法】选取6月龄敖汉细毛羊公羊30只,分别进行宰前禁食0 h（对照）、12 h和24 h处理,研究羊肉食用品质（pH值、肉色、剪切力、持水力）、感官品质（膻味、嫩度、多汁性、总体可接受性）、卫生品质（菌落总数、大肠菌群总数）及宰后成熟过程中糖原含量、肌节长度和肌原纤维蛋白降解程度的变化规律。【结果】宰前禁食24 h处理组羊肉在宰后0 h、45 min、4 h的pH显著高于禁食12 h组和对照组（P＜0.05）。随着成熟时间延长,pH值差异逐渐消失,3个处理组之间羊宰后24 h和48 h pH差异不显著（P＞0.05）。宰前禁食24 h组羊肉蒸煮损失显著低于禁食12 h组和对照组（P＜0.05）。3个处理之间羊肉L*、a*、b*、ΔE、滴水损失、剪切力值及感官评价膻味、嫩度、多汁性和总体可接受性打分差异均不显著（P＞0.05）。宰后成熟24 h后,不同宰前禁食时间处理组羊肉的菌落总数及大肠菌群总数均在国标规定范围之内,不同处理组之间羊肉菌落总数差异不显著（P＞0.05）。随禁食时间的延长大肠菌群总数呈下降趋势,宰前禁食处理组羊肉大肠菌群菌落总数低于对照组。3个宰前禁食处理组羊宰后0 h、45 min、4 h、8 h、12 h、24 h、48 h羊肉的糖原含量差异不显著（P＞0.05）。随宰后成熟时间的延长,糖酵解程度加大,糖原含量呈下降趋势。随宰前禁食时间的延长,肌节长度增加。宰前禁食24 h处理组肌节长度大于禁食12 h处理组,禁食12 h处理组肌节长度大于对照组（P＜0.05）。宰前禁食处理组羊肉宰后0 h羊肉肌原纤维蛋白降解程度一致,没有显著条带出现或缺失。宰后成熟24 h时,3个处理组在27 kD均出现条带,且宰前禁食12 h和24 h处理组的27 kD条带颜色深于对照组,表明禁食12 h和24 h处理组羊肉蛋白降解程度高于对照组。【结论】宰前禁食12 h和24 h使羊宰后肌肉卫生品质提高,并且促进宰后蛋白质降解。宰前禁食24 h使蒸煮损失降低。宰前禁食12 h和24 h对羊肉极限pH、糖原含量及肉质指标无影响。与对照组相比,宰前禁食12 h和24 h有益于羊肉卫生品质,对食用品质及感官品质无影响。     

不同杂交组合改良甘肃高山细毛羊效果分析

为筛选不同品种对本地绵羊杂交改良的最优组合,以黑萨福克、无角陶赛特为父本,甘肃高山细毛羊为母本,研究杂交F₁代羔羊(无角陶赛特羊和甘肃高山细毛羊杂交后代简称“陶甘细”,黑萨橘克羊和甘肃高山细毛羊杂交后代简称“黑萨甘细”）及对照（甘肃高山细毛羊）的生长性能、屠柔性能和肉品质。生长观测表明,陶甘细1~6月龄生长速度高于黑萨甘细（P<0.01）,陶甘细平均日增量为199.8 g,高于黑萨甘细（P<0.01）;4月龄（断奶前）、黑萨甘细平均日增量最快,分别为276.6 g和244.0 g;屠宰性能表明,陶甘细热胴体质量、屠宰率、净肉率均极显著高于黑萨甘细（P<0.01）;肉品质测定表明,陶甘细嫩度优于黑萨甘细,根据新西兰羊肉分级标准,陶甘细肉质为PL级,黑萨甘细为ML级,陶甘细的肉品质优于黑萨甘细。可见：两杂交组合各项指标均高于对照组,且无角陶赛特对甘肃高山细毛羊改良效果优于黑萨福克。     

Effects of Dietary Isoflavone Supplementation on Meat Quality and Oxidative Stability During Storage in Lingnan Yellow Broilers

To investigate the effects of a synthetic isoflavone （SI） on meat quality and oxidative stability, 1 500 43-d-old Lingnan yellow male broilers were randomly assigned to five dietary treatments： diets supplemented with 0, 10, 20, 40, or 80 mg SI kg-1, fed ad libitum for a period of 3 wk. After refrigerated storage, a＊ value of the meat increased with dietary SI supplementation using 10 and 40 mg kg-1 level （P〈0.05）, L＊ value decreased （P〈0.05）, and 40 mg kg-j increased the pH （P〈0.05）. Supplementation with SI, at all levels, increased water holding capacity （P〈0.05） and decreased lactic acid content of meat （P〈0.05）. The concentration of malondialdehyde at 72 h decreased linearly （P=0.005） and quadratically （P=0.004） with increasing levels of SI. Dietary SI at 20 and 40 mg kg-1 levels enhanced total superoxide dismutase activity in meat （P〈0.05）. Meat pH quadratically decreased as the storage time increased （P〈0.05）, with the highest value at 24 h （P〈0.05）. Lactic acid and malondialdehyde concentrations of meat increased over time, with value at 96 h being far higher than at earlier times （P〈0.05）. Supplemental SI linearly and quadratically increased the mRNA abundance ofglutathione peroxidase （GPX） （P=0.001 and P=0.002） and catalase （CAT） （P=0.003 and P=0.006） in breast muscle. The results from this study indicate that dietary supplementation with SI can improve meat quality during refrigerated storage by decreasing lipid peroxidation and enhancing oxidative stability and, for male broilers from 43 to 63 d of age, the optimal level of SI was 40 mg kg-1.     

宰前因子对牛肉品质的影响

 【目的】探讨宰前因子对牛肉品质的影响,得出DFD（dark firm dry）牛肉的判定标准。【方法】研究某企业DFD肉的发生率,并挑选600头延边×西门塔尔杂交公牛进行不同的宰前处理,通过测量牛胴体背最长肌的pH、温度以及品质指标,对劣质牛肉的发生率及牛肉品质进行分析。【结果】宰前因子中待宰密度、温湿度以及短途运输对DFD肉的发生影响不大;而屠宰时间、季节、待宰时间和屠宰方式对劣质牛肉（PSE肉、DFD肉）的发生都有不同程度的影响;牛肉品质的颜色指标中b*比L*更具有作为判定劣质牛肉标准的意义;DFD牛肉的判定标准为pH24＞6.09,L*＜37.40±3.78,b*＜10.25±1.94,汁液损失值＜7.36%±2.81%。【结论】在冬季清晨,待宰24 h、击晕屠宰的肉牛DFD肉发生率较低;夏季、清真屠宰的肉牛PSE肉发生率较高;科学、规范的宰前管理可以降低肉牛的应激反应,有效减少劣质牛肉的发生;牛肉pH24＞6.09,品质会产生较大的差异。     

不同杂交组合羔羊产肉性能的研究

利用短期育肥试验研究了无角陶赛特羊不同杂交组合羔羊的产肉性能,结果表明:陶蒙F3公羔平均日增重304.50 g.d-1,比陶寒F3母羔267.50 g.d-1高37.00 g.d-1,两者间的差异显著(P<0.05).经育肥后陶蒙F3公母羔屠宰率分别为50.62%和49.68%,均高于陶寒F3公母羔,陶蒙F3和陶寒F3屠宰率与对照相比差异极显著(P<0.01).陶蒙F3公母羔胴体净肉率分别为77.58%和75.96%.陶蒙F3和陶寒F3大理石纹在3~4之间,剪切力3~4 kg,失水率小,肉质柔嫩多汁.育肥组羔羊与对照组相比每只多获纯利分别是89元和67元,经济效益明显.无角陶赛特羊杂交改良当地现有绵羊品种杂交优势明显,陶蒙F3杂交组合优于陶寒F3.     

A longitudinal study of the effect of time on the matching performance of a retinal recognition system for lambs

While there is strong evidence supporting retinal vascular pattern as a distinctive marker for sheep, it would be advantageous to get an insight into its robustness; in other words, to determine whether retinal recognition of young animals (lambs) can reach as good a matching performance as the one demonstrated for adult sheep. To this aim, a longitudinal study was devised to observe the evolution of matching scores (ms) of lamb retinal images (n = 38) acquired from 1 to 22 weeks after birth. It was observed that four lamb retinas (out of 38) underwent slight curving of one or two secondary arteries, which ceased by the time they were 6–8 weeks old. However, this slight artery curving did not affect matching performance. A random effects statistical model demonstrated that lamb age had an effect (P < 0.01) on the matching scores produced using this commercially available retinal recognition system. As lambs grew older (larger eyes) and they became easier to handle, retinal images of progressively better quality could be obtained in a more consistent way; and thus matching scores increased from an average of 86 at the first week of life, up to an average of 96 by week 8. Dunnett simultaneous tests of means indicated that no further improvement in matching score took place once lambs were at least 6–8 weeks old, meaning that the retinal image quality became by then optimal and consistent. Although the variable retinal image quality of younger lambs (1–4 weeks old) caused a reduction in matching score, they did not lead to false non-matches in any case (considering a cut-off matching score of 70 for acceptance of a positive match). Therefore, the results of these trials have shown that, with the available technology, retinal images can be used as a robust biometric marker of lambs from 1 week of age.     

Effect of dioscorea opposite waste on growth performance,blood parameters,rumen fermentation and rumen bacterial community in weaned lambs

This study investigated the effects of dioscorea opposite waste(DOW) on the growth performance, blood parameters, rumen fermentation and rumen microbiota of weaned lambs. Sixty healthy weaned Small-Tailed Han lambs(male,(22.68±2.56) kg initially) were used as the experimental animals. Four levels of concentrate: 0(control, CON), 10%(DOW1), 15%(DOW2) and 20%(DOW3), were replaced with DOW in the basal diet as experimental treatments. The results showed that lambs fed the DOW2 diet had a higher(P&l...     

EGF和β-巯基乙醇对羔羊卵母细胞体外受精和体外发育的影响

[目的]为优化幼畜卵母细胞体外培养体系提供理论基础。[方法]研究在成熟液中添加EGF和β-巯基乙醇对绵羔羊卵母细胞受精和卵裂、囊胚情况的影响,并与成年绵羊卵母细胞进行比较。[结果]在成熟液中添加不同浓度的EGF对羔羊卵母细胞卵裂率和囊胚率无显著影响(P0.05)。添加不同浓度的β-巯基乙醇可以提高羔羊卵母细胞囊胚率,其中添加100μmol/Lβ-巯基乙醇有显著影响(P0.05),但对卵裂率影响不显著(P0.05)。羔羊卵母细胞卵裂率和囊胚率均显著低于成年羊(P0.05)。添加100μmol/L的β-巯基乙醇能显著提高羔羊卵母细胞正常受精率(P0.05),且与成年羊卵母细胞受精率差异不显著(P0.05)。未添加β-巯基乙醇多精入卵率显著高于成年羊(P0.05),而添加100μmol/L的β-巯基乙醇多精入卵率与成年羊差异不显著(P0.05)。成熟液中不添加β-巯基乙醇时未受精率(20.0%)高于成年羊组(12.3%)和β-巯基乙醇(13.5%),但差异不显著(P0.05)。[结论]添加100μmol/L的β-巯基乙醇能显著提高羔羊卵母细胞发育能力,提高正常受精的比例并减少多精子受精的发生,但羔羊卵母细胞发育能力仍显著低于成年羊。     

Evaluation of Physicochemical,Microbiological and Sensory Stability of Frozen Stored Vacuum-Packed Lamb Meat

Nowadays, lamb meat represents only 7% of all meat produced in the world. In recent years the demand for standardized lamb meat cuts has been considered of great importance and the marketing occurs predominantly in the form of frozen cuts. Herewith, the main of this work was to evaluate the stability and safety of lamb meat during frozen storage. Meats were vacuum packed in high barrier multilayer plastic iflms and stored during 12 mon at （-18±1）℃. The meat stability was assessed by physical and chemical （lipid oxidation, objective color, pH value, cooking losses and instrumental texture）, microbiological （total count of psychrotrophic, coliform count at 45℃, coagulase-positive staphylococci and the presence of Salmonella） and sensory analysis （acceptance test and visual evaluation）. The vacuum packed lamb meat remained stable as to most physical and chemical indexes. Microbiological indexes showed good stability throughout the storage period according to Brazilian legislation standards to pathogenic microorganisms. Although a signiifcant reduction in tenderness （shear force increase from 3 to 8 kg）, it showed a good sensorial acceptance for all attributes tested, including texture, with scores of around 7 （like moderately） during the 12 mon of storage. Therefore, it can be concluded that, under the conditions applied in this study, lamb meat presents a shelf life of at least 12 mon when stored at-18℃.     

Long term effects of artificial rearing before weaning on the growth performance,ruminal microbiota and fermentation of fattening lambs

Early life intervention is important to shape the gut microbiome profiles of adult animals due to the tremendous alteration of diet components. Nevertheless, there is still no unified understanding about its long-term effects in lambs. In this study, sixty 20-day-old lambs were assigned into ewe-rearing (ER) and artificial-rearing (AR) treatments to evaluate the effects of AR strategy on ruminal microbiota, fermentation, and morphology of pre-weaning lambs (from 20 to 60 days of age) and its long-term effects in the fattening stage (from 61 to 180 days of age). During the pre-weaning stage, ER lambs were breastfed and supplemented starter, while AR lambs were artificially fed with milk replacer and starter. During the fattening stage, all lambs in both treatments were fed with the same fattening diets. At 60, 120 and 180 days of age, 6 lambs from each group were slaughtered to collect rumen content and tissue samples. Compared with ER lambs, the dry matter feed intakes of AR lambs increased (P<0.05) from 20 to 180 days of age, companying an increased average daily gain (ADG) from 61 to 120 days of age (P<0.05) and from 121 to 180 days of age (0.05<P<0.1). Although there was no difference in short-chain fatty acid (SCFA, including acetate, propionate, and butyrate) between treatments before weaning (P>0.05), it was higher (P<0.05) in AR lambs compared with ER lambs at the fattening stage. The rumen keratin layer of AR lambs was thinner (P<0.05) than that of ER lambs. Along with lamb growth from 60 to 180 days of age, the differences in rumen bacterial diversity between AR and ER treatments grew more distinct (P<0.05). Compared with ER lambs, AR lambs increased (P<0.05) rumen bacteria abundance, such as phylum Spirochaetes and genus Treponema at 60 days of age, phylum Actinobacteria and genus Succiniclasticum at 120 days of age, and phylum Proteobacteria at 180 days of age, but decreased genus Selenomonas from 60 to 180 days of age, and Anaerovibrio at 180 days of age. In summary, the early interventions before weaning could improve dry matter feed intake of lambs, which triggered robust rumen development and produced positive long-term effects on rumen fermentation and noticeable weight gain of fattening lambs. It suggests that the artificial rearing strategy is effective in improving rumen fermentation and microbial maturity of intensive fattening lambs.     

和田多胎红羊屠宰性能及6月龄羊肉成分分析

【目的】研究新疆和田多胎红羊的屠宰性能及羊肉成分,为其开发利用提供参考。【方法】选取6月龄羔羊、12月龄周岁羊、2岁成年羊3个阶段的和田多胎红羊公羊各6只,对其屠宰性能及6月龄羔羊羊肉成分进行测定。【结果】6月羔羊的屠宰率与成年羊之间差异性极显著（P<0.01）,与周岁羊之间差异性显著（P<0.05）;是否将脂尾作为净肉,6月龄羔羊的净肉率和骨肉比都与周岁羊及成年羊之间差异性极显著（P<0.01）;除周岁羊骨肉比外,脂尾对不同年龄阶段和田多胎红羊的净肉率及骨肉比均造成显著性差异（P<0.05）;6月龄和田多胎红羊羊肉水分足、粗脂肪含量（98.00±0.95 g/kg）,氨基酸、矿物质种类丰富,其中磷元素（1 600.00±2.66 mg/kg）、油酸（41.30±1.71 g/kg）、硬脂酸（17.40±1.30 g/kg）,含量水平相对较高。【结论】周岁羊及成年羊的胴体品质要优于6月龄羊,6月龄和田多胎红羊有待加强管理;脂尾对和田多胎红羊的屠宰性能影响较大;6月龄和田多胎红羊羊肉成分较为全面,营养价值较高。