肉用羔羊舍饲育肥效果

根据肉用羔羊生理特点及营养需要配制营养丰富、安全无副作用的精料补充料。在全舍饲条件下对20只小尾寒羊(3～4月龄)进行饲喂试验,另20只在当地传统方式下饲喂试验,作为对照组。经35d试验,结果表明,试验全期试验组平均日增重比对照组多111g,每只平均多盈利37.5元。     

舍饲育肥羔羊补饲舔块对育肥效果的影响

以农作物秸秆为主适当添加农作物籽实的肉羊舍饲育肥方式 ,在青海省较为普遍。在此基础上添加价格低廉的复合营养舔块饲料。结果舔块处理组羊的总增重比对照组羊多 2 .6 5kg ,舔块处理组平均日增重比对照组提高了 2 7.4 % (P<0 .0 1) ,在外貌和行为表现上也好于对照组羊 ,同时可明显提高经济效益。表明给育肥羔羊补饲舔块是一种安全、使用方便、有效的营养补充方式。     

舍饲羔羊育肥的要点

舍饲羔羊育肥就是应用合理的饲养和管理方法,在圈舍内以最短的时间、最少的饲料及管理成本获得最快的增重速度,生产出肉质鲜嫩、营养丰富的优质羔羊肉,从而取得最高的经济效益。     

复合益生素对肉用羔羊增重效果的试验

河南省养殖业中草食反刍动物在畜禽业中所占的比例越来越大，研究复合益生素对羔羊生产性能的影响对河南省的养殖业发展及提高养殖业经济效益具有极为重要的现实意义。将复合菌益生素添加到羔羊的饲料中，观察复合菌益生素对肉用羔羊生长发育的影响，以便为以后的肉羊生产提供参考依据。     

良种羔羊舍饲育肥日粮筛选试验

设计4种日粮配方,经92d育肥,结果表明:试验1～4组平均日增重分别为244、224、167和189g,屠宰率、净肉率和眼肌面积和GR值等指标都以第一组最优,但经济效益排列顺序为第2、第1、第4和第3组。     

脲酶抑制剂育肥羔羊效果试验

在羔羊添加脲酶抑制剂育肥试验中，试验组平均体重43．2kg，比对照组提高20．7％（P＜0．01），日增重提高30．8％，饲料利用率提高15％，投入产出比为1∶2．1－1∶2．8。试验组比对照组每天每只多收入0．31元。     

冬季羔羊舍饲育肥中应用膨润土的试验研究

在玉米秸为主的日粮中每头添加膨润土16 g/d和羟甲基尿素20 g/d进行羔羊快速育肥试验.结果表明,羔羊日增重由对照组的65.00 g提高到试验组的120.63 g,二者差异显著(P＜0.05).饲料转化效率提高46.01%.40 d后羔羊瘤胃液pH值明显降低.膨润土能改善羔羊瘤胃消化代谢并促进羔羊生长.     

冬季羔羊舍饲育肥中应用膨润土的试验研究

在玉米秸为主的日粮中每头添加膨润土１６ｇ／ｄ和羟甲基尿素２０ｇ／ｄ进行羔羊快速育肥试验。结果表明,羔羊日增重由对照组的６５．００ｇ提高到试验组的１２０．６３ｇ,二者差异显著（Ｐ＜０．０５）。饲料转化效率提高４６．０１％。４０ｄ后羔羊瘤胃液ｐＨ值明显降低。膨润土能改善羔羊瘤胃消化代谢并促进羔羊生长。     

羔羊高效舍饲育肥技术

羔羊育肥就是利用羔羊生长发育快、饲料报酬高、生产周期短、肉质鲜嫩多汁、便于集约化生产的特点,通过采取相应的技术,如利用杂交优势、合理分群、科学搭配日粮、早期断奶等饲养管理技术措施,经过60～90d育肥,育肥到5～8月龄时,体重达到35～42kg时上市,从而获得最佳屠宰率、胴体重、优质羔羊肉和可观的经济效益。     

放牧时间对羊肉多不饱和脂肪酸沉积及氧化稳定性的影响

分析不同放牧时间对羊肉抗氧化性能的影响。选择40只乌珠穆沁去势公羔,按照体重和出生月份接近的同质原则随机分成5个处理组:舍饲组(0H,对照),放牧2 h组(2H)、放牧4 h组(4H)、放牧8 h组(8H)和放牧12 h组(12H)。舍饲组圈养,4个放牧组在清晨6:00出牧,依组次分别在8:00、10:00、14:00和18:00归牧。试验期102 d,预试期15 d,正式期87 d。放牧试验结束后,从各组挑选体重接近的6只屠宰,取背最长肌,测定多不饱和脂肪酸(PUFA)和抗氧化物浓度。结果表明,1)放牧时间显著影响羊肉中抗氧化物的浓度。舍饲组的丙二醛(MDA)含量显著(P<0.001)高于4个放牧组,且4个放牧组之间差异不显著。放牧4~12 h组的谷胱甘肽过氧化物酶(GSH-Px)显著(P=0.020)低于舍饲组,但其超氧化物歧化酶(SOD)显著(P<0.001)高于舍饲组。总抗氧化能力(T-AOC)在各组间差异不显著。2)放牧时间与羊肉中的MDA、SOD水平呈二次曲线关系,MDA先降低,至放牧10 h后升高,SOD先升高,至放牧10 h后降低;GSH-Px水平与放牧时间呈负线性关系,放牧时间越长其值越低。3)放牧4,12 h组的PUFA和高度氧化多不饱和脂肪酸(HP-PUFA)均显著高于放牧2 h和舍饲组(P<0.01)。PUFA和HP-PUFA沉积量与抗氧化物浓度之间关系密切。绵羊每天放牧2~10 h,可以改善羊肉的氧化稳定性,防止PUFA氧化,从而延长高品质羊肉的保质期。     

道赛特、萨福克与阿勒泰羊杂交公羔育肥效果对比试验

选用2.5月龄、体重相近、健康无病的断奶道赛特×阿勒泰(DAF1、DAF2)、萨福克×阿勒泰(SAF1、SAF2)杂交一、二代公羔各15只,阿勒泰羊(ALT)10只进行60d育肥试验。试验结果表明:SAF1、DAF1日增重为269g和262g,分别比ALT提高24.54%、21.30%,差异极显著(P<0.01);SAF2、DAF2日增重为258g和254g,分别比ALT提高19.44%、17.59%,差异显著(P<0.05),SAF1、DAF1、SAF2、DAF2日增重相互间差异不显著(P>0.05);育肥期内,每只杂交羊纯增直接经济收入分别比ALT多30.42、32.95、28.12、30.21元。     

Controlling microbial contamination on beef and lamb meat during processing

SUMMARY The microbiological quality of carcases, meat and environmental surfaces was evaluated in commercial boning rooms processing beef and lamb. There was considerable variation in the level of microbial contamination on both carcases and meat, with counts ranging from less than 20 to 10⁸/cm² on carcases and to 2 times 10⁷/cm² on meat. The level of microbial contamination on meat was influenced by the level of carcase contamination at boning and by the boning process itself. Carcase contamination was the major determinant of microbiological quality, as more than 70% of carcases had microbial counts greater than 10³/cm². Cutting boards were a major source for microbial dissemination during boning, particularly when carcase counts were less than 10³/cm². If carcases were heavily contaminated, the contamination of processing surfaces was irrelevant in determining microbial loads on meat. Where carcase contamination was at low to moderate levels, the contribution of the boning process to the contamination on meat assumed increased significance. Under these conditions, improved sanitation of cutting surfaces in the boning room resulted in a significant reduction in microbial contamination on the surface of meat. These results can form the basis for ensuring that improvements made in carcase management before boning, to improve microbiological quality, will be preserved through attention to cutting board hygiene during boning.     

The effects of dietary hesperidin supplementation on lamb performance and meat characteristics

An experiment was conducted to examine the effects of supplementing feed with hesperidin or α‐tocopheryl acetate on lambs' growth performance, carcass and meat characteristics. Sixteen male lambs were randomly assigned to four groups. One of the groups served as control and was given a basal diet, whereas the other three groups were given the same diet further supplemented with hesperidin at 1500 mg/kg, or hesperidin at 3000 mg/kg, or α‐tocopheryl acetate at 200 mg/kg. At the end of the experiment, lambs were fasted, weighed and slaughtered. After overnight chilling, samples of Longissimus thoracis muscle were taken and were used for meat quality evaluation. No significant differences were observed in final body weight, body weight gain and organ weights among the four groups. pH, color, water‐holding capacity, shear force values and intramuscular fat concentration of Longissimus thoracis muscle were also not significantly influenced by the dietary treatments. Measurement of lipid oxidation values showed that hesperidin supplementation positively influenced meat antioxidant properties during refrigerated storage.     

富含共轭亚油酸羔羊肉营养调控的研究进展

本文对羔羊肉营养特性及富舍CLA的羔羊肉营养调控进行综述.     

Rigor temperature and meat quality characteristics of lamb longissimus muscle

The present experiment was conducted to determine the effect of muscle temperature during the prerigor and early postrigor period on meat tenderness, postmortem proteolysis, calpain system activity, water-holding capacity, and color. Lamb longissimus muscle (n = 14) from the right and left carcass sides was excised immediately after dressing, divided into an anterior and posterior sample, vacuum-packaged, and stored overnight at 5 to 35 degrees C. Further storage, up to 14 d postmortem, was at 2 degrees C. Tenderness at 1 d postmortem, tenderization during further storage, and postmortem proteolysis were negatively affected by overnight incubation above 25 degrees C. This effect could be explained by an effect of temperature on muscle contraction and activity of the calpain system. Muscle contraction was at a minimum after incubation at 15 degrees C. Water-holding capacity was negatively affected by incubation above 25 degrees C. Color scores improved with increasing incubation temperature at 1 d postmortem. However, after 14 d of postmortem storage, no differences in color scores were observed. Based on the present results and results of other groups, a temperature around 15 degrees C at the onset of rigor seems optimal to maximize tenderness without having detrimental effects on water-holding capacity or color.     

An evaluation of the lamb vision system as a predictor of lamb carcass red meat yield percentage

An objective method for predicting red meat yield in lamb carcasses is needed to accurately assess true carcass value. This study was performed to evaluate the ability of the lamb vision system (LVS; Research Management Systems USA, Fort Collins, CO) to predict fabrication yields of lamb carcasses. Lamb carcasses (n = 246) were evaluated using LVS and hot carcass weight (HCW), as well as by USDA expert and on-line graders, before fabrication of carcass sides to either bone-in or boneless cuts. On-line whole number, expert whole-number, and expert nearest-tenth USDA yield grades and LVS + HCW estimates accounted for 53, 52, 58, and 60%, respectively, of the observed variability in boneless, saleable meat yields, and accounted for 56, 57, 62, and 62%, respectively, of the variation in bone-in, saleable meat yields. The LVS + HCW system predicted 77, 65, 70, and 87% of the variation in weights of boneless shoulders, racks, loins, and legs, respectively, and 85, 72, 75, and 86% of the variation in weights of bone-in shoulders, racks, loins, and legs, respectively. Addition of longissimus muscle area (REA), adjusted fat thickness (AFT), or both REA and AFT to LVS + HCW models resulted in improved prediction of boneless saleable meat yields by 5, 3, and 5 percentage points, respectively. Bone-in, saleable meat yield estimations were improved in predictive accuracy by 7.7, 6.6, and 10.1 percentage points, and in precision, when REA alone, AFT alone, or both REA and AFT, respectively, were added to the LVS + HCW output models. Use of LVS + HCW to predict boneless red meat yields of lamb carcasses was more accurate than use of current on-line whole-number, expert whole-number, or expert nearest-tenth USDA yield grades. Thus, LVS + HCW output, when used alone or in combination with AFT and/or REA, improved on-line estimation of boneless cut yields from lamb carcasses. The ability of LVS + HCW to predict yields of wholesale cuts suggests that LVS could be used as an objective means for pricing carcasses in a value-based marketing system.     

不同蛋白营养水平精补料对黄渠桥羊羔肉氨基酸含量的影响

试验研究了不同蛋白营养水平精补颗粒料对羔羊生长育肥性能的影响,试验选择出生15 d、体质量在10 kg左右的哺乳羔羊,采用随机分组试验设计,羔羊与母羊钻栏补饲的方法,通过饲喂不同营养水平的精补颗粒料,检测羔羊目标体质量达23 kg左右时,屠宰测定其羊肉氨基酸含量的变化。结果表明:羔羊早期补饲有利于羔羊增重,在羔羊生长到38日龄后,其体质量以试验Ⅰ组增长最快;饲喂不同蛋白水平精补颗粒料羔羊肉背最长肌中蛋白质含量、必需氨基酸含量及其占总氨基酸比例均是Ⅰ组均高于Ⅱ组、Ⅲ组和Ⅳ组,但组间差异不显著(P>0.05);同一饲养环境下,不同蛋白水平精补颗粒料饲喂羔羊其背最长肌肉中氨基酸风味各有不同,但差异不明显(P>0.05)。结果提示,以补饲颗粒精料粗蛋白18.5%和代谢能11.34 MJ/kg水平组合羔羊日增质量及其背最长肌中蛋白质含量、必需氨基酸含量等优势比较明显。     

日粮多不饱和脂肪酸对畜禽肉品质的影响

近年来,因为多不饱和脂肪酸(Polyunsaturated fatty acids,PUFA)独特的生物学功能,富含PUFA的畜禽产品的开发与利用成为热点,同时PUFA对畜禽肉品质的影响也备受关注。日粮中添加PUFA能够增加肉品中PUFA的含量,提高营养价值,但PUFA的强氧化性对其他肉品指标会产生影响。本文叙述PUFA对畜禽肉产品脂肪沉积、嫩度、系水力、风味和贮存性状等方面的影响,旨在为畜禽日粮的配制和人类膳食提供指导。