羔羊代乳料的研究与使用

目前,国内外对犊牛和仔猪的早期断奶及代乳料和开食料的研究较多,相比之下,对羔羊的早期断奶及补饲效果报道甚少。在我国,从20世纪60年代开始曾先后开展了犊牛早期断奶时的试验研究并取得了一定的成绩。由于羔羊的现代化、集约化的生产,要求全进全出,这样羔羊的早期断奶就显得尤为重要,同时羔羊的代乳料的研究也就更加重要,本文将对代乳料研制和使用过程中的一些问题做一简述。     

羔羊早期断奶技术研究进展

对近年来羔羊早期断奶技术在断奶时间、代乳料以及过渡方式等内容研究取得的新进展进行整理归纳,以期能为肉羊养殖获得更高的经济效益提供参考。     

代乳料饲喂羔羊早期断奶试验研究

研究用3个不同配方的代乳料对羔羊进行早期断奶,对羔羊体重、成活率、体尺等指标的影响。选择80只25日龄杂交羔羊(小尾寒羊和本地羊),随机分为4组进行试验。3个试验组5日龄内用代乳料逐渐代替母乳,另一组为对照组(自然哺乳)。结果表明:①试验1组、2组、3组的只均日增重分别为:203.25 g、238.45 g、241.50 g、高于对照组的150.60 g,差异显著(P0.05);②试验组羔羊体高、尻高、胸围、体长均高于对照组,试验组间无明显差异;③试验组成活率为100%,比对照组95%有所提高;④试验组羔羊断奶时每只均利润比对照组增加了40元以上。     

不同配方代乳料对羔羊生长发育的影响

试验用3个不同配方的代乳料对羔羊进行早期断奶,研究其对羔羊体重、成活率、体尺等指标的影响.选择80只25日龄的无角陶赛特羔羊,随机分为4组进行试验.3个试验组5日龄内用代乳料逐渐代替母乳,另一组为对照组(自然哺乳).结果表明:①试验Ⅰ组、Ⅱ组、Ⅲ组的只均日增重分别为:223.25、256.67和257.25 g,高于对照组的159.29 g,差异显著(P<0.05);②试验组羔羊体高、尻高、胸围、体长均高于对照组,试验组间无明显差异;③试验组成活率为100%,比对照组95%有所提高;④试验组羔羊断奶时只均利润比对照组增加了40元以上.     

早期断奶羔羊饲喂代乳料的研究

针对母羊产奶不足会影响羔羊的生长发育及肉羊规模化生产的需要,该试验对人工哺喂羔羊代乳料的效果进行了研究.采用单因子随机分组设计,将24只羔羊(无角陶赛特♂×小尾寒羊♀的F1代)随机分为3组,分别为对照组、试验组Ⅰ和试验组Ⅱ,试验组饲喂代乳料和优质干草,对照组自然哺乳和饲喂优质干草,进行了60 d的饲养试验.结果表明,对羔羊实行早期断奶饲喂代乳料是可行的,饲喂代乳料的羔羊和自然哺乳羔羊生长发育速度差异不显著(P>0.05).     

不同断奶时间及代乳料对放牧羔羊生长的影响

试验设计3个不同断奶时间(30 d,45 d,60 d)和3个不同营养水平的代乳料,研究这两个因素对放牧条件下甘肃高山细毛羊羔羊生长性能的影响。结果表明:在45 d断奶时,饲喂代乳料Ⅲ的羔羊在60 d时体重比对照组高4.35 kg,差异极显著(P<0.01),该组平均每只羔羊比对照组的经济效益高27.58元;60 d断奶时,饲喂代乳料Ⅲ的羔羊在75 d时体重比对照组高5.26 kg,差异极显著(P<0.01),该组平均每只羔羊的经济效益比对照组高29.51元。     

早期断奶对巴音布鲁克羊羔羊增重及血清中部分生长类激素水平的影响

选择巴音布鲁克羊健康羔羊20只,分别在40和60日龄实施早期断奶,同时饲喂2种不同粗蛋白质水平(20%、22%)的代乳料,测定血清中生长类激素水平,研究早期断奶对羔羊生长的影响。试验分为4个试验组(A、B、C、D组,2种断奶日龄分别对应2种粗蛋白质水平代乳料)和1个对照组(哺乳羔羊)。结果表明:①平均日增重,试验组羔羊均高于对照组,其中饲喂22%CP代乳料的2种断奶日龄组显著高于对照组(P0.05);22%CP的2组平均日增重显著高于20%CP的2组(P0.05);同一营养水平的代乳料,2种断奶日龄间平均日增重无显著差异。②血清中4种生长类激素的水平,试验组羔羊血清中IGF-Ⅰ、INS水平均高于对照组,其中B组(40日龄断奶,22%CP)IGF-Ⅰ显著高于对照组(P0.05);B、D组(22%CP)INS显著高于对照组(P0.05);B组IGF-Ⅰ显著高于A、C、D组(P0.05)。试验组羔羊血清中T3、T4浓度与对照组无显著差异(P0.05)。因此,本试验条件下,巴音布鲁克羊羔羊40和60日龄断奶可行,且以饲喂粗蛋白质水平为22%的代乳料效果较好。     

羔羊代乳料对雷州山羊生长性能、养分表观消化率、瘤胃发酵参数和菌群结构及健康状况的影响

本试验旨在研究羔羊代乳料对雷州山羊生长性能、养分表观消化率、瘤胃发酵参数和菌群结构及健康状况的影响。选取体重相近、出生20日龄的健康雷州山羊公羔48只，分为代乳料组（饲喂代乳料+开食料）和母乳组（饲喂母乳+开食料），每组24个重复，每个重复1只羔羊。预试期10 d，正试期40 d。结果表明：1）代乳料组羔羊40日龄平均个体重、21～40日龄平均日增重及干物质、粗蛋白质、粗脂肪和粗灰分的表观消化率均显著低于母乳组（P<0.05）;21～40日龄，代乳料组开食料平均日采食量显著高于母乳组（P<0.05），但平均日总采食量却显著低于母乳组（P<0.05），且腹泻率极显著高于母乳组（P<0.01）。2）代乳料组羔羊60日龄平均个体重、41～60日龄和21～60日龄平均日增重及各养分表观消化率均与母乳组相比差异不显著（P>0.05）；代乳料组41～60日龄和21～60日龄开食料平均日采食量均极显著高于母乳组（P <0.01）；代乳料组41～60日龄平均日总采食量显著高于母乳组（P<0.05），但21～60日龄2组间差异不显著（P>0.05）；代乳料...     

代乳料对羔羊增重的对比试验

为了解代乳料对早期断奶羔羊的饲喂效果,选择8群青海毛肉兼用细毛羊,分为8组(对照组4组,试验组4组),每组180只,其中对照组羔羊由母羊自由哺乳和放牧,试验组羔羊由母羊自由哺乳+补喂代乳料和放牧。结果表明,通过饲喂代乳料,基本可以解决在枯草季节,牧草中蛋白质减少时羊群生长发育缓慢的现象。     

内蒙古：推广肉羊高效技术

一是推广羔羊早期断奶技术。重点围绕羔羊代乳料饲养、羔羊早期补饲等环节开展技术推广,使羔羊实现早期断乳,确保羔羊在转入育肥期能迅速达到上市标准。同时通过缩短母羊的哺乳期,可使母羊提早发情,提前配种,实现反季节生产。     

羔羊代乳粉蛋白质来源和水平的研究进展

代乳粉对羔羊早期断奶至关重要.本文综述了羔羊早期断奶的意义和代乳粉的饲喂效果以及代乳粉的蛋白质来源与水平,并对羔羊代乳粉的发展趋势进行了展望.     

羔羊代乳粉研究进展及其在肥羔生产中的应用前景

文章从羔羊代乳粉的研究进展及其在羔羊早期断奶中的应用等几个方面进行了阐述,分析了肥羔生产的产业优势及产业现状,认为羔羊代乳粉是肥羔规模化、工厂化、产业化生产的主要技术条件,应用前景广泛.     

Effect of different feeding regimes on pre‐weaning growth rumen fermentation and its influence on post‐weaning performance of lambs

Influence of pre‐weaning live weight on post‐weaning growth performance was assessed on thirty‐nine 15‐day‐old Indian native lambs, randomly fed in three equal groups until 180 days of age. During pre‐weaning phase lambs were maintained under feeding regimen of grazing (C‐0; Control), grazing and ad lib creep mixture supplementation (C‐AL) or grazing, with ad lib creep mixture and milk replacer supplementation (C‐ALMR). Lambs were allowed to suckle respective dam in morning and evening till 90 days of age, and fed ad lib green leaves of Ailanthus excelsa after grazing. After weaning all lambs were maintained on grazing and ad lib finisher concentrates supplementation. Pre‐weaning performance of lambs in terms of weaning weight (17.2 kg), average daily gain (ADG; 154 g) and feed conversion ratio 3.73 was higher (p < 0.01) in C‐ALMR lambs but total gain and ADG were similar among three groups during post‐weaning phase. However, improved pre‐weaning plane of nutrition and growth rate increased (p < 0.01) finishing weight (FW) of lambs in C‐AL, 33 kg and C‐ALMR, 32 kg. Dry matter intake was significantly (p < 0.01) higher in C‐AL and C‐ALMR lambs due to combined effect of feeding. Rumen pH was lowest (p = 0.049) in C‐AL lambs. Rumen ciliate protozoa population (10⁴/ml) decreased in C‐ALMR lambs (4.3) but increased in C‐AL lambs (50.0) more so in C‐0 Lambs (19.8). Concentrate feeding of C‐AL lamb improved nutrient digestibility. Lambs of C‐0 group consumed more DM during post‐weaning phase that improved growth performance, while nutrient digestibility was not affected by pre‐weaning nutrition. Thus, pre‐weaning nutrition has significant influence on FW, however influence of milk replacer feeding on lamb growth need further studies.     

Sheep rumen metabolic development in response to age and dietary treatments

This study examined the time course of rumen metabolic development in the absence of solid feed consumption and the effect of delayed solid feed consumption on sheep rumen development. Twenty-seven lambs consumed milk replacer until slaughter at nine ages from 1 to 84 d (milk group). Three additional lambs consumed milk replacer from 1 to 48 d. From 49 d until slaughter at 84 d, these lambs were weaned onto solid feed (fed group). At slaughter, rumen contents were removed for VFA analysis and rumen epithelium was preserved for morphological examination. Rumen epithelial cells were isolated and incubated in media containing 2.5 mM U-[14C]-glucose or 10 mM 1-[14C]-butyrate. Rumen VFA concentrations did not change with age in lambs given milk replacer. At 84 d of age, intraruminal VFA concentrations were elevated in lambs consuming solid feed compared to 84-d-old lambs given milk replacer (P < .05). The number of ruminal papillae per square centimeter decreased (P < .05) while papillae length and width did not change significantly with age in rumen epithelium from lambs given milk replacer. At 84 d of age, rumen epithelium from lambs in the fed group had fewer and larger papillae/per square centimeter than rumen epithelium from lambs given milk replacer (P < .05). Rates of glucose and butyrate oxidation and acetoacetate and lactate production by rumen cells isolated from lambs given milk replacer did not change with age. Beta-hydroxybutyrate (BHBA) production was undetectable before 42 d of age in lambs given milk replacer and increased to levels found in conventionally raised adults by 84 d. At 84 d there were no differences in rates of glucose and butyrate oxidation or acetoacetate and lactate production by rumen cells between the two treatment groups. Thus, the change in substrate oxidation from glucose to butyrate, indicative of rumen metabolic maturation, does not occur in the absence of solid feed consumption. However, the development of rumen ketogenesis, as evidenced by increased BHBA production, does occur in the absence of solid feed consumption. Delaying the initiation of solid feed consumption results in rumen morphological development but does not stimulate rumen metabolic development. Increased intraruminal VFA concentrations, earlier exposure to VFA, or a longer period of exposure to VFA may be required to induce the genes responsible for rumen metabolic development.     

代乳料原料组成对早期断奶羔羊生长及脏器发育的影响

为了探讨代乳料原料的不同组合效应对早期断奶羔羊的饲喂效果,选取25只甘肃高山细毛羔羊,分为5组,每组5只,对照组羔羊由母羊自由哺乳和放牧;试验组羔羊30日龄断奶,饲喂4种代乳料:A组主原料未膨化,B组主原料膨化,C组主原料膨化+血浆蛋白粉,D组在C组基础上增加乳清粉。试验期为30~90日龄。结果表明:50、70日龄时,对照组羔羊体质量最大,试验组羔羊受断奶应激的影响,相应指标较小。90日龄时,D组体质量显著高于B、C组(P0.05),超过了对照组。30~90日龄阶段,D组日增体质量最大,且显著高于B、C组(P0.05)。对照组脾脏质量显著高于4个试验组(P0.05),且脾脏指数最高。说明在代乳料中添加血浆蛋白粉及增加乳清粉,有利于羔羊健康发育,使代乳料的饲喂效果最佳。     

湖羊羔羊早期断奶前后瘤胃发酵与微生物区系的变化

本试验旨在研究湖羊羔羊早期断奶前后的瘤胃发酵与微生物区系变化，为幼龄反刍动物瘤胃发育变化理论以及羔羊的早期培育等提供依据。选择初生重接近的湖羊公羔（3.81 kg±0.55 kg）16只，1~7日龄饲喂母乳，8日龄与母羊分离，开始饲喂代乳粉（按8日龄体重的2%，分3次等量饲喂）和开食料（自由采食），35日龄断奶。分别于断奶前（21日龄）、后（42日龄）各选择5只羔羊进行屠宰，采集瘤胃内容物，测定瘤胃发酵、酶活和微生物区系。结果表明，断奶后羔羊的瘤胃总挥发性脂肪酸、乙酸、丙酸、丁酸及纤维素酶和α-淀粉酶活性均极显著高于断奶前（P<0.01）。断奶后瘤胃菌群多样性和丰富度均低于断奶前（P<0.05）。断奶前后的优势菌门均为拟杆菌门（Bacteroidetes）和厚壁菌门（Firmicutes），其中，拟杆菌门为第一优势菌门，在断奶前后分别占61.96%和65.36%，厚壁菌门为第二优势菌门，在断奶前后分别占32.08%和24.03%；两菌门之和在断奶前后分别占瘤胃总菌门的94.04%和89.39%。断奶前后的优势菌属均为unidentified_Prevotellaceae，分别占21.85%和38.49%。断奶前后羔羊瘤胃微生物的功能没有显著变化，都主要集中在复制和修复、碳水化合物代谢和翻译等途径。以上结果说明，羔羊早期断奶后的瘤胃发酵和酶活增强，菌群多样性和丰富度有所降低，在早期断奶前后的优势菌群和功能相似。     

湖羊羔羊早期断奶前后瘤胃发酵与微生物区系的变化

本试验旨在研究湖羊羔羊早期断奶前后的瘤胃发酵与微生物区系变化,为幼龄反刍动物瘤胃发育变化理论以及羔羊的早期培育等提供依据。选择初生重接近的湖羊公羔(3.81 kg±0.55 kg)16只,1~7日龄饲喂母乳,8日龄与母羊分离,开始饲喂代乳粉(按8日龄体重的2%,分3次等量饲喂)和开食料(自由采食),35日龄断奶。分别于断奶前(21日龄)、后(42日龄)各选择5只羔羊进行屠宰,采集瘤胃内容物,测定瘤胃发酵、酶活和微生物区系。结果表明,断奶后羔羊的瘤胃总挥发性脂肪酸、乙酸、丙酸、丁酸及纤维素酶和α-淀粉酶活性均极显著高于断奶前(P<0.01)。断奶后瘤胃菌群多样性和丰富度均低于断奶前(P<0.05)。断奶前后的优势菌门均为拟杆菌门(Bacteroidetes)和厚壁菌门(Firmicutes),其中,拟杆菌门为第一优势菌门,在断奶前后分别占61.96%和65.36%,厚壁菌门为第二优势菌门,在断奶前后分别占32.08%和24.03%;两菌门之和在断奶前后分别占瘤胃总菌门的94.04%和89.39%。断奶前后的优势菌属均为unidentified_Prevotellaceae,分别占21.85%和38.49%。断奶前后羔羊瘤胃微生物的功能没有显著变化,都主要集中在复制和修复、碳水化合物代谢和翻译等途径。以上结果说明,羔羊早期断奶后的瘤胃发酵和酶活增强,菌群多样性和丰富度有所降低,在早期断奶前后的优势菌群和功能相似。     

早期断奶对藏西北绒山羊背最长肌氨基酸和脂肪酸含量的影响

[目的] 研究早期断奶对藏西北绒山羊背最长肌中氨基酸和脂肪酸含量的影响。[方法] 将18只健康羔羊按照体重相近原则随机分为试验组和对照组,试验组在28日龄（D28）实施早期断奶,对照组在60日龄（D60）自然断奶,羔羊断奶后饲喂相同的代乳料至75日龄;从两组随机选取5只羔羊进行屠宰采样,对其背最长肌中氨基酸和脂肪酸指标进行测定分析。[结果] 在藏西北绒山羊背最长肌中检测出17种氨基酸,包括赖氨酸、亮氨酸等7种必需氨基酸,天冬氨酸、精氨酸等10种非必需氨基酸。两组断奶羔羊肉中总氨基酸含量、必需氨基酸含量、非必需氨基酸含量均无显著差异（P>0.05）,28日龄断奶组羔羊肉中EAA/TAA、EAA/NEAA比值显著（P<0.05）高于60日龄断奶羔羊。共检测出29种饱和脂肪酸、不饱和脂肪酸,以棕榈酸和油酸含量最高,早期断奶对羔羊肉中饱和脂肪酸含量、单不饱和脂肪酸含量以及多不饱和脂肪酸含量影响不显著（P>0.05）。[结论] 藏西北绒山羊羔羊肉中所含氨基酸和脂肪酸种类多、含量丰富,实施早期断奶、及早补充颗粒料对肉中脂肪酸和氨基酸含量无影响,且可提高EAA/TAA、EAA/NEAA比值,使其更符合FAO/WHO氨基酸评分模式;该试验可为藏西北绒山羊羔羊实施早期断奶、提高母羊的繁殖率提供参考。     

饲喂代乳粉对羔羊生长性能和体组织参数的影响

研究饲喂代乳粉和母羊哺乳对羔羊生长性能和体组织参数的影响。选取18只日龄和体重相近、健康的杂交F1羔羊,随机分成试验组和对照组,每组9只。试验组饲喂代乳粉,对照组随母羊哺乳,饲养时间为90d。称取20、90日龄空腹体重,并于90日龄时每组随机选取4只屠宰,称量胴体、各胃室、小肠各段、内脏器官鲜重。结果表明:与对照组相比,试验组羔羊平均日增重提高18.61%(P0.05);宰前活体重、胴体重分别提高22.28%、32.44%(P0.05),屠宰率提高6.67%(P0.05);复胃总重增加13.25%(P0.05),其中瘤胃鲜重增加25.92%(P0.05),皱胃鲜重提高6.74%(P0.05),网胃和瓣胃鲜重则有降低的趋势;回肠鲜重和长度分别增长75.28%(P0.05)和35.50%(P0.05);肺、肾脏、肝脏和脾脏鲜重提高22.29%、30.10%、28.86%和38.22%(P0.05)。结论:饲喂代乳粉后可提高羔羊生长性能,但对屠宰率无显著影响,可促进其瘤胃的发育,并影响部分内脏器官发育。     

Economic analysis of feeding pasteurized nonsaleable milk versus conventional milk replacer to dairy calves

OBJECTIVE: To determine growth, morbidity, and mortality rates in dairy calves fed pasteurized nonsaleable milk versus commercial milk replacer and compare economics of feeding pasteurized nonsaleable milk versus commercial milk replacer in dairy calves. DESIGN: Clinical trial. ANIMALS: 438 dairy calves. PROCEDURE: Calves were assigned at 1 to 2 days of age to be fed pasteurized nonsaleable milk or a commercial milk replacer until weaned. Body weight was measured at the time of study enrollment and at the time of weaning, and any medical treatments administered and deaths that occurred prior to weaning were recorded. A partial budget model was developed to examine the economics of feeding pasteurized nonsaleable milk versus commercial milk replacer. RESULTS: Calves fed conventional milk replacer had significantly lower rates of gain (-0.12 kg/d [-0.26 lb/d]), lower weaning weights (-5.6 kg [-12.3 lb]), higher risk for treatment during the summer and winter months (odds ratio [OR], 3.99), and higher risk of death during the winter months (OR, 29.81) than did calves fed pasteurized nonsaleable milk. The estimated savings of feeding pasteurized nonsaleable milk, compared with milk replacer, was dollars 0.69/calf per day. The estimated number of calves needed to economically justify the nonsaleable milk pasteurization system was 23 calves/d. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that dairy calves fed pasteurized nonsaleable milk have a higher growth rate and lower morbidity and mortality rates than do calves fed conventional milk replacer. Feeding pasteurized nonsaleable milk could be an economically viable strategy for dairy calf producers.