安杂牛、西杂牛、弗杂牛犊牛早期断奶试验报告

本试验在国家肉牛牦牛产业技术体系张掖综合试验站肉牛繁育场应用犊牛代乳料开展了不同杂种犊牛的早期断奶试验,旨在研究早期断奶技术对不同杂种肉用犊牛生长发育以及犊牛代乳料适应性等的影响,以此为张掖市牛源基地建设提出可供借鉴的依据。结果表明:安杂牛(安格斯×西杂)、西杂牛(西门塔尔×河西黄牛)、弗杂牛(弗莱维赫×西门塔尔)三组间日增重差异不显著(P0.05),安杂牛组增重成本8.25元/kg,当地西杂牛组9.27元/kg,弗杂牛组9.62元/kg。安杂牛组的效益略好,弗杂牛组效益略差。在骨骼的生长发育上,从累计增长的效果来看,安杂牛组同比相同阶段龄的西杂牛与弗杂牛组间体直长与体斜长变化差异极显著(P0.01)。结果表明:在张掖自然资源条件下,经过本试验方案的试验观测,犊牛早期断奶成本低,效果好,安杂牛较西杂牛和弗杂一代牛相比,生长发育快,增重效果好,建议在张掖市及其同类地区推广使用犊牛代乳料,并实施犊牛早期断奶技术,提高对肉用杂种犊牛的培育效果。     

添加苜蓿草块对不同品种肉牛育肥效果的影响

在相同环境条件下,试验在三种苜蓿草块添加量下对不同品种肉用牛进行五期的育肥效果研究.通过测定不同品种的体重、日增重及粗饲料采食量,来比较不同品种肉牛增重效果试验结果表明:在精粗比下降的情况下,添加苜蓿草块能起到提高日增重的效应与不添加相比,荷斯坦牛组表现差异极显著(P<0.01),新褐杂牛组前后差异显著(PO.05).苜蓿草块的添加在本试验营养水平与体重下,新褐杂组、荷斯坦组、安杂组各组适宜的添加量分别为1.2kg、1.2kg、O.5kg.结合农区养牛的现状及生产力水平在低精粗比的情况下,肉牛应该首先考虑使用本地优良品种.     

品种、季节因素对放牧犊牛生长发育的影响

时3月龄安杂牛、新褐杂牛、荷斯坦牛公犊进行放牧补饲.结果表明,在相同饲养管理条件下,安杂犊牛、新褐杂犊牛、荷斯坦犊牛在5-8月份夏季天然草场平均日增重差异不显著(P>0.05),受季节性的牧草质量及连续放牧食入性牧草营养水平变化等因素影响,不同月份平均日增重水平差异显著(P<0.05).随着动物生长需要的增加与牧草营养的变化,犊牛在6月上旬有一个生长高峰,之后在7月上旬也有一个相对增重高峰,7月下旬至试验结束,平均日增重持续下降.三种犊牛在体高、腰角宽指标上差异显著(P<0.05).结论:肉牛补饲从6月下旬开始较适宜,补饲量根据生产计划做适当调整.     

添加苜蓿草块对不同品种肉牛育肥效果的影响

在相同环境条件下,试验在3种苜蓿草块添加量下对不同品种肉用牛进行5期的育肥效果研究。通过测定不同品种的体重、日增重及粗饲料采食量,来比较不同品种肉牛增重效果。试验结果表明,在精粗比下降的情况下,添加苜蓿草块能起到提高日增重的效应,与不添加相比,荷斯坦组差异极显著（P<0.01）,新褐杂组前后差异显著（P<0.05）,安杂组差异不显著（P>0.05）。在本试验营养水平与体重下,新褐杂组、荷斯坦组、安杂组各组苜蓿草块适宜的添加量分别为1.2、1.2、0.5 kg。结合农区养牛现状及生产力水平在低精粗比的情况下,肉牛应该首先考虑使用本地优良品种。     

胚胎移植犊牛早期断奶技术的研究与应用

利用本地黄牛胚胎移植的荷斯坦奶牛犊牛,设计奶牛42日龄、50日龄早期断奶方法的两种不同方案(试验Ⅰ组、试验Ⅱ组),分别与常规60日龄断奶方法(对照组)进行了对比试验。结果表明:早期断奶有利于犊牛早期的生长发育和骨骼发育,显著提高犊牛60日龄的体重、日增重及其体高和胸围,同时能显著降低犊牛的培育成本,其中试验Ⅰ组(即犊牛出生后4天开始采食,第1周每天喂6 kg牛奶和150 g犊牛料,以后每周增加200 g犊牛料、减少1 kg牛奶,第6周龄每天喂料1 200 g,停止喂牛奶)60日龄体重、日增重、体高及胸围分别为91.10 kg、0.91 kg、82.90 cm和93.70 cm,较常规的60日龄断奶犊牛分别提高20.30%、35.80%、10.20%、12.20%(P<0.05),犊牛培育成本397.20元/头,较对照组降低成本35.80%。     

奶公犊牛早期断奶试验研究

公犊牛早期断奶可以节省鲜奶，降低饲养成本，促进消化系统的发育.试验对奶公犊牛30日龄断奶，60日龄时测定结果.结果表明：试验组牛增重49.8 kg，每增重1kg体重需要成本13.25元，比正常饲喂组低5.79元/kg。     

高寒地区中国荷斯坦犊牛早期断奶方案对犊牛生长发育、腹泻与培育成本的影响

[目的]研究高寒地区中国荷斯坦犊牛早期断奶方案的推广价值。[方法]选取1周内新生、体重相近的犊牛16头,采用对照的试验方法将16头犊牛随机分为试验组和对照组,每组8头。试验组为早期断奶方案,对照组为常规断奶流程,试验期为90 d。[结果]试验组在60日龄与90日龄的日增重均显著高于对照组（P〈0.05）。试验组90日龄增重显著高于对照组（P〈0.05）。对照组犊牛30日龄内腹泻发病率为100%,重复发病率为75%;试验组30日龄内腹泻发病率为50%,重复发病率为50%。试验组与对照组相比节约成本32.52%。[结论]高寒地区中国荷斯坦犊牛可实行早期断奶方案,且能够提高企业和养殖户的经济效益,具有较好的推广价值。     

断奶日龄对和荷杂犊牛生长性能的影响

研究早期断奶对肉用犊牛生长发育和养殖效益的影响。采用对比试验方法,对120、90、60日龄断奶的和荷杂犊牛体重、体尺等生长指标和养殖效益进行分析。结果表明:人工哺乳条件下,和荷杂犊牛在120、90、60日龄断奶,饲养至150日龄时,试验Ⅰ组、Ⅱ组、Ⅲ组犊牛的体重、胸围、体斜长、体高、十字部高差异不显著(P>0.05),各组试验牛90、120和150日龄体重、胸围、体斜长、体高、十字部高与60日龄比较,试验Ⅲ组的增幅显著高于试验Ⅰ组、Ⅱ组。经济效益分析表明:试验牛饲养至150日龄,试验Ⅲ组饲料成本和增重成本最低、增重净收入最高。综合比较,在人工哺乳条件下,对和荷杂犊牛60日龄实施断奶最佳,生长发育好,养殖效益高。     

不同断奶月龄对新疆褐牛生长发育性能和犊牛腹泻发生的影响

本试验旨在探究早期断奶对新疆褐牛生长发育及犊牛腹泻的影响,为新疆褐牛科学饲养提供参考。试验选取出生日期、体重相近的新疆褐牛犊牛180头,随机分为两组,每组90头,在舍饲条件下通过特定营养配方方案,分别在4月龄(试验组)与6月龄(对照组)时进行断奶处理,比较试验两组生长发育情况差异并对饲养成本进行核算比较。结果表明,试验组与对照组在体尺、体重与日增重上差异均不显著(P0.05);试验组比对照组节省饲养成本339.70元,日节省饲养成本1.90元;试验组腹泻率与粪便指数两项指标均优于对照组。本试验方案下新疆褐牛犊牛在4月龄断奶时犊牛生长发育与对照组无明显差异,但早期断奶饲喂成本较低,能有效降低腹泻发生。     

新疆褐牛犊牛补饲试验效果分析

[目的]为探讨新疆褐牛犊牛补饲对其生长发育以及经济效益的影响,[方法]试验选取新疆褐牛犊牛20头,分为试验组和对照组,试验组犊牛在哺乳的基础上补饲精料,4月龄断奶,对照组分阶段饲喂,6月龄断奶。同时测定4月龄、6月龄的体高、体斜长、胸围、管围、体重并计算日增重和经济效益。[结果]结果表明,与对照组相比,4月龄试验组在体高、体斜长有着明显的提高,6月龄试验组在体斜长、胸围、管围、体重和日增重也有着明显的提高,但均为达到显著水平(P0.05)。经济效益分析结果表明,通过犊牛早期补饲可明显提高农牧民收入,节约饲养成本,相比传统饲喂方式每头犊牛饲养至6月龄可节约成本342元。[结论]综上,早期补饲对可提高新疆褐牛犊牛的生长性能,对改善养殖经济效益,提高经济收入有着显著的效果。     

断奶犊牛补饲配合精料配方筛选

[目的]为了筛选出适合攀枝花市地区断奶犊牛补饲配合日粮营养配方。[方法]选1.5~3月龄、体重100~180 kg的西本杂犊牛共32头,随机分为4组,开展断奶犊牛补饲配合精料配方筛选试验。[结果]经90 d的育肥,Ⅰ、Ⅱ、Ⅲ、Ⅳ组头均增重分别为40.63 kg、试验46.38 kg、46.5 kg和47.63 kg。日增重Ⅱ、Ⅲ、Ⅳ组较I组分别提高14.16%、14.47%、17.24%;Ⅲ、Ⅳ组较Ⅱ组分别提高0.27%、2.70%;Ⅳ组较Ⅲ组提高2.42%,组间差异均不显著（P〉0.05）。从经济效益看,I、Ⅱ、Ⅲ、Ⅳ、组头均纯收入分别为102.6元、219.44元、174.63元、140.02元,Ⅱ组较I组提高113.88%、较Ⅲ组提高25.66%、较Ⅳ组提高56.72%,Ⅱ组的经济效益高于其它组。[结论]试验结果表明,Ⅱ号配方是断奶西杂犊牛较为理想的补饲配合精料配方。     

Sire breed effects in matings with Angus cows: I. Fertility, calf survival and performance to 18 months

Over six calf crops, 524 exposures of Angus cows to three sire breeds resulted in 432 weaned calves for an 82.4% calf crop. Least-squares means for weaning rate by sire breed were 81.8, 80.5 and 83.9% for Angus, Charolais and Holsteins, respectively. Sire breed effect was not significant for calving rate, calf mortality or overall weaning rate, but was significant for all growth traits from birth to 18 mo. Angus-sired calves were smallest at birth, grew at a slower rate and were lightest in weight at all ages. Charolais-sired calves were heaviest at all weigh periods and Holstein-sired calves were intermediate. Holstein-sired calves scored significantly lower for both grade and condition than did Angus- and Charolais-sired calves. Charolais-sired calves had the highest grade. Calving rate tended to be influenced by the effect of cow (P less than .10) and sire breed X year (P less than .001). Calving rate was highest for 3-yr-old and for 6- to 10-yr-old cows and was also 1.5 percentage units higher for crossbred matings. Cow productivity (kg of calf weaned/cow exposed) is a combined measure of fertility, calf survival and weaning weight. Although sire breed did not significantly affect cow productivity (P less than .20), actual values favored cows producing crossbred calves by 14 and 9 kg for Charolais and Holstein crosses, respectively. Likewise, weight differences at 18 mo favored these crosses by 50 and 32 kg for heifers and 72 and 62 kg for steers. Among the two crossbred types, Charolais X Angus heifers were 28 kg heavier (P less than .05) than Holstein X Angus heifers at 18 mo but the 10 kg difference in steers was not significant. The fact that the large sire breeds produced calves with heavier weaning weights without demonstrating significant increases in overall productivity points out the importance of high weaning rates.     

基于主成分逐步回归法的新疆褐牛体重预测模型研究

[目的]为了找到适合新疆褐牛体重预测的方法。[方法]运用主成分回归分析法构建了新疆褐牛公牛体重模型,消除了常用估重方法中体尺指标间普遍存在的多重共线性模型。[结果]表明,该模型具有较高的精度(R2=0.810,P0.01),估测体重与实测体重具有较高的拟合度(R=0.922,P0.01)。[结论]这种方法适合新疆褐牛的体型结构特点,同时,该方法与模型的应用也为其他品种牛体重估测模型的构建提供了参考。     

Breed effects on crossbred cow-calf performance

Effects of seven breeds of cow's sire and 12 breeds of cow's maternal grandsire on preweaning performance of crossbred cows and their calves were examined in data from two experiments conducted at the Roman L. Hruska U.S. Mean Animal Research Center. Data included 1,836 records over three to five parities for 516 cows by 143 sires and by 307 maternal grandsires. The statistical model fitted effects of calf sex, parity, cow birth-breeding year or cow-calf birth year, the breed effects and their interactions. Deviations of breed of sire or equivalent grandsire effects on each trait from the mean for Hereford x Angus cows ranged from -1.6 to 5.5 kg (P less than .001) for calf birth weights, -15 to 1% (P less than .001) for calving difficulty, nonsignificant for preweaning calf mortality and -2 to 27 kg (P less than .001) for calf weaning weight. Deviations were nonsignificant for conception rate and calves weaned per cow exposed to breeding, but -2 to 40 kg (P less than .001) for calf weight weaned per cow exposed for breeding, -7 to 78 kg (P less than .001) for cow weight and -20 to 2% (P less than .001) for body condition score. The advantages of Holstein and Brahman cross over Hereford x Angus cows of 23 and 13% in weight of calf weaned/cow-breeding exposure must be compared with the expected greater feed requirements from 7 or 8% heavier cows and at least 50% higher milk production, which emphasizes the need to include input measures and costs in breed evaluation schemes.     

Comparison of Charolais and Limousin as terminal cross sire breeds

Birth, weaning, feedlot and carcass traits were evaluated on 1,181 calves sired by Charolais and Limousin bulls out of eight crossbred dam groups (Hereford X Angus, Angus X Hereford, Simmental X Angus, Simmental X Hereford, Brown Swiss X Angus, Brown Swiss X Hereford, Jersey X Angus, Jersey X Hereford). Calves were born in the spring over a 4-yr period during which dams ranged from 3 to 8 yr of age. Charolais-cross calves were 2.7 kg heavier (P less than .01) at birth and had a 9.9% higher (P less than .01) incidence of difficult calvings and 4.6% greater (P less than .05) preweaning death loss than did Limousin crosses. Charolais-sired calves out-gained Limousin-sired calves by 31 g/d (P less than .01) from birth to weaning and were 9 kg heavier (P less than .01) at weaning. After weaning, calves were self-fed a finishing diet and slaughtered as each animal attained an estimated carcass grade of low Choice. Charolais-cross calves gained 60 g/d faster (P less than .01) than Limousin crosses, were fed 6.8 fewer d and were 17.3 kg heavier (P less than .01) at slaughter. Feed efficiency was similar for both sire breeds. On a grade-equivalent basis, Charolais crosses produced 7 kg heavier (P less than .01) carcass and had 22 g more carcass weight per day of age (P less than .01). Charolais crosses had slightly less internal and external fat. Dressing percentage was higher for Limousin cross calves (64.6 vs 63.9%, P less than .01). Longissimus muscle area and carcass cutability were similar for crosses of both sire breeds.     

牛胚胎移植试验及其后代生长发育指标测定

为探讨牛胚胎移植受胎率、产犊成活率及后代生长发育情况,互助县先后从新疆呼图壁种牛场胚胎工程中心引进不同品种牛冷冻胚胎93枚,进行了胚胎移植试验.结果表明：平均受胎率为45.16%,产犊成活率为90.48%.黑白花、西门塔尔、利木赞、安格斯犊牛平均初生重为40.77,42.50,47.41,39.13,分别比同龄本地牛提高71.82%,79.10%,99.79%,64.90%;六月龄平均体重分别为116.74,123.36,134.15,120.49,分别比同龄本地牛提高64.80%,74.13%,89.37%,70.09%;12月龄体重分别为253.31,289.91,302.73,271.35,分别比同龄本地牛提高75.18%,100.51%,109.36%,87.66%;1周岁平均日增重分别为582.30g,677.84g,699.50g,636.22g.胚胎移植后代牛的生长发育较本地牛快.     

Characterization of breeds of Bos indicus and Bos taurus cattle for maternal and individual traits

Angus, Boran and Red Poll sires were mated to Ankole, Boran and small East African Zebu (Zebu) females to produce the cows characterized in this study, which produced calves by Friesian, Brown Swiss, Simmental, Boran and Red Poll sires. Individual traits included cow parturition weight, cow weight at weaning, cow mean weight and cow weight change from parturition to weaning; maternal traits included calf crop born percentage, preweaning viability percentage, overall viability percentage, birth weight, weaning weight, weight at 12, 18 and 24 mo and calf weight weaned per cow exposed to breeding (productivity index). Cows by Angus and Red Poll sires significantly exceeded cows by Boran sires (all cows in this comparison had Ankole and Zebu dams) in weaning weight of progeny and in cow weight at parturition and at weaning. Cows by Red Poll sires significantly exceeded cows by Boran sires in birth weight of progeny. Progeny of cows by Boran sires significantly exceeded progeny of cows by Angus and Red Poll sires in 24-mo weight. Cows by Angus and Red Poll sires did not differ (P greater than .05) in any of the traits analyzed. Cows with Ankole and Boran dams significantly exceeded cows with Zebu dams (all cows in this comparison had Angus and Red Poll sires) in progeny weight at birth, 18 mo and 24 mo and in cow weight at parturition and at weaning. Cows with Boran dams significantly exceeded cows with Zebu dams in weaning and 12-mo weight of progeny and significantly exceeded cows with Ankole dams in weaning weight of progeny. The significantly heavier weaning weight and significantly lighter 24-mo weight of the 3/4 Bos taurus progeny of cows with Angus and Red Poll sires relative to the 1/2 Bos taurus progeny of cows with Boran sires suggest that cattle that are 1/2 Bos taurus breed composition have greater general adaptation than cattle with 3/4 Bos taurus breed composition in the postweaning nutritive and climatic environment under which this experiment was conducted. Significantly heavier weights of Angus and Red Poll crossbred cows relative to Boran crossbred cows (all breeds crossed on Ankole and Zebu cows) indicate that the two Bos taurus breeds exceed the Boran (Bos indicus) breed in additive direct genetic effects for size when they have general adaptation to the environment.     

饲喂蒸汽压片玉米对新疆褐牛增重、瘤胃发酵及微生物多样性的影响

【目的】通过研究饲喂蒸汽压片玉米对新疆褐牛增重、瘤胃发酵及微生物的影响,旨在探索提高肉牛增重性能和饲养效益的饲喂方法。【方法】将16头年龄(18月龄)和体重相近(436.87 kg±17.29 kg)的健康新疆褐牛公牛随机分为2组,每组8头牛。试验组精料使用蒸汽压片玉米,对照组使用普通破碎玉米,预试期15 d,正试期180 d。记录试验牛初始体重、终末体重并计算平均日增重。于试验第180天采集新疆褐牛饲喂前(0 h)和饲后1、3、5、7、9 h瘤胃液测定瘤胃发酵指标;取0 h瘤胃液利用16S rRNA分析瘤胃微生物菌群组成。【结果】与对照组相比,试验组褐牛平均日增重显著提高(P＜0.05);瘤胃液pH在1 h显著降低(P＜0.05),在3 h极显著降低(P＜0.01);瘤胃液乙酸和乙酸＋丙酸＋丁酸含量在3 h均显著提高(P＜0.05),丙酸含量极显著提高(P＜0.01);在各采样时间点,瘤胃液氨态氮和微生物蛋白含量均极显著升高(P＜0.01)。两组褐牛瘤胃液Chao1指数和Shannon指数差异均不显著(P＞0.05),在门水平上,试验组拟杆菌门相对丰度显著提高(P＜0.05),螺旋菌门相对丰度极显著提高(P＜0.01),而厚壁菌门、脱硫杆菌门、疣微菌门相对丰度均显著降低(P＜0.05),放线菌门相对丰度极显著降低(P＜0.01);在属水平上,试验组理研菌科RC9、普雷氏菌属UCG-003、毛螺旋菌科XPB1014和毛螺旋菌科NK3A2相对丰度均显著提高(P＜0.05),而克里斯滕森菌科R-7相对丰度显著降低(P＜0.05)。【结论】饲粮中使用蒸汽压片玉米能显著提高新疆褐牛公牛平均日增重,改变瘤胃发酵速度,提高发酵效率,显著增加与碳水化合物和挥发性脂肪酸代谢相关的微生物丰度,降低了纤维降解相关和可致病的微生物丰度。     

不同肉牛品种杂交西门塔尔杂种牛效果的研究

为了研究不同肉牛品种杂交改良西门塔尔杂种牛的效果,筛选出产肉量高、肉质好、抗逆性强的品种杂交组合,为大规模开展杂交提供依据,试验采用红安格斯、利木赞、夏洛莱(法系)、德国黄牛4个品种牛,分别杂交西门塔尔杂种母牛,产犊后从每个杂交组合中选择11头断奶小公牛,在相同饲养管理条件下持续育肥至18月龄,并进行屠宰和肉质评定。结果表明:红安西杂组合杂交效果最好,其次是利西杂及夏西杂,德黄西杂组合杂交效果较差。说明在生产实际中,如果采用断奶小公牛持续育肥至18月龄时出栏、屠宰,应优先选择红安格斯×西门塔尔杂交组合。