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.     

藏羔羊生长规律的观察及消维康的保育效果

对62只哺乳期羔羊按不同时期的体重增长分析了羔羊哺乳期的生长规律，发现在自然放牧条件下，初生重对羔羊生长速度影响不大，1月龄生长速度最快，日增重118－123g，3-4月龄生长速度下降（日增重44.74-46.84g)，5月龄生长又加快，日增重为61.33-81.33g，这与羔羊生长发育的营养需求及羔羊摄入的草料关系密切，羔羊灌服消维康比未服药组成活率提高11．92％，5月龄时每只羔羊多增重2.42kg。     

澳·本杂F1代与本地黄牛的增重对比试验

2003年至2005年,农业部"948"项目-澳洲矮牛引进及开发试验利用项目在湖南省永顺县顺利实施并通过验收,澳洲矮牛在该县投放以来,澳.本杂牛表现出良好的适应性和增重优势。本次试验通过对6月龄澳.本杂F1代公牛与本地公黄牛在相同放牧补饲条件下,进行体重增重的对比试验,结果表明F1代杂交牛的日增重和9月龄体重均大于本地牛,F1代平均日增重比本地牛大203g,9月龄平均体重比本地牛重49.43kg,生长优势明显;在试验过程中,澳.本杂F1代对本地的饲养条件适应性表现良好。     

云南省肉牛饲养配套技术研究

用2-6月龄、6-12月龄、12-25月龄和2岁以上云南黄牛及其杂交牛分别在舍饲和放牧条件下，研究杂交改良、补充肉牛浓缩料、精料补充料及驱虫对其采食量、日增重、单位耗料量、生理生化指标的影响，制定科学的肉牛饲养配套技术。结果表明：杂交改良牛的采食量、日增重、饲料效率均优于云南黄牛；犊牛、生长牛在传统饲料基础上添加浓缩料和驱虫。其日粮的粗蛋白、钙、磷和微量元素得到提高，改善了目前农村肉牛的营养水平；后期育肥牛在传统饲养的基础上增加肉牛补充料和蛋白质，明显改善了日粮营养水平，生产性能各项指标显著提高。100头中试试验，云南黄牛在人工草场放牧情况下，驱虫和补饲2kg肉牛精料补充料，日增重613g，比传统饲养提高68．87％。在舍饲条件下，日增重达780g，提高64．56％；杂交牛在同样条件下，日增重分别达866g和l159g，比未补饲牛分别提高59．19％和84．55％，是传统饲养云南黄牛的1．39倍和1.45倍。     

新疆褐牛犊牛放牧补饲试验效果分析

[目的]为了研究新疆褐牛犊牛放牧补饲增重效果.[方法]选择4～6月龄新疆褐牛80头作为研究对象,随机分为试验组和对照组,在不同饲养条件下进行日增重效果对比试验.[结果]表明:放牧加补饲的日增重效果明显优于纯放牧的饲养方式(P＜0.01);新疆褐牛公犊和母犊的日增重效果差异不显著;放牧加补饲的新疆褐牛犊牛在第1个月和第2...     

暖季草场不同放牧方式对牦牛藏羊生产力的影响

为探讨中度放牧条件下放牧方式对家畜生产力的影响，开展了牦牛单牧（YG）、藏羊单牧（SG）、牦牛藏羊1∶6混牧（MG1∶6）、牦牛藏羊1∶4混牧（MG1∶4）和牦牛藏羊1∶2混牧（MG1∶2）5个控制性放牧试验，研究了牧草生长季不同生长时期对家畜日增重的影响以及不同放牧方式对牦牛和藏羊暖季增重、牧草营养和家畜采食量的影响。结果表明：1）在牧草返青期和生长期，牦牛和藏羊的日增重显著大于牧草枯黄期（P<0.05）;2）牦牛和藏羊日增重在不同的放牧方式下无显著差异（P>0.05），而牦牛暖季增重在YG下最高，在MG1∶2和MG1∶6相对较高，藏羊暖季增重在MG1∶2中最高，在SG和MG1∶4相对较高；3）不同放牧方式下牧草营养和单位面积家畜采食量无显著差异（P>0.05），单一家畜放牧单位面积增重SG最高，牦牛藏羊两种家畜混合放牧则MG1∶2单位面积增重最高。综上，牧草枯黄期牦牛和藏羊的补饲对于维持其生产性能具有重要的意义，且MG1∶2对于牦牛和藏羊生产是一种较优的组合生产方式。     

草地放牧制度及其评价

根据近期国外发表的有关资料和刊物关于草地放牧制度评价方面的论述及研究结果，对连续放牧与划区轮牧两种放牧制度对草地家畜增重，牧草生长，家畜营养摄入和家畜行为的影响进行综述，认为影响草地牧草生长及家畜表现各方面的并不同放牧制度本身，而与其载畜率及采用的放牧技术手段和放牧条件有关。     

不同饲养方式下合作猪的生长性能

通过舍饲养殖,研究不同饲养方式下合作猪的生长性能。结果显示:1～6月龄舍饲组合作猪体重、体高、体长、胸围均极显著高于放牧组(P<0.01);头长和管围差异不显著(P>0.05)。合作猪初生～1月龄、3～6月龄日增重,放牧组显著低于舍饲组(P<0.05);1月龄到3月龄日增重,2组差异不显著(P>0.05)。2组合作猪绝对生长在6月龄为最大,放牧组为103.00 g,舍饲组为150.67 g。2组合作猪相对生长系数随日龄的增加而下降,体重的生长强度随月龄的增加逐渐减小。     

半牧半舍饲养条件下科尔沁牛生长特性和生产性能

【目的】为研究内蒙古半牧半舍饲养条件下科尔沁牛的生长规律和生产性能。【方法】2014年4月~2015年4月选取内蒙古通辽市扎鲁特旗5处养殖户多头样本,测量和分析初生、6月、12月、18月和24月龄科尔沁牛生长特性。【结果】科尔沁公牛和母牛体重均随月龄的延长呈直线增加,初生和6月龄,科尔沁公牛和母牛的体重没有显著性差异(P0.05),但12月龄、18月龄和24月龄科尔沁公牛体重均显著高于母牛体重(P0.05),公牛体重分别比母牛体重高20.9%、36.07%和42.58%。公牛日增重在0.61~0.95kg/cm。18月龄和24月龄科尔沁公牛肉用指数分别为3.82和4.61。【结论】科尔沁牛乳肉兼用牛,在以放牧为主舍饲为辅的条件下,具有较好的生长发育特性和生产性能,适合本地区的养殖,但为提高生产效率,有待进一步加强饲养管理和饲料利用效率。     

不同放牧强度对家畜生产性能与牧草干物质体外消化率的影响

于2010—2012年间在内蒙古锡林郭勒盟正镶白旗克氏针茅草原进行了不同载畜率的放牧试验,研究了草地家畜生产性能与牧草干物质体外消化率在不同放牧强度下的变化。结果表明,不同放牧强度下牛日增重呈显著差异(P<0.05),且均随放牧强度的增加而下降;不同放牧强度下单位公顷牛日增重在MG区显著高于LG区和HG区(P<0.05);不同放牧强度下MG区牧草体外消化率显著高于LG区(P<0.05),且随放牧时间的推移牧草体外消化率逐渐下降。在同时考虑家畜体重与牧草消化率的情况下,放牧强度应控制在0.35～0.40头/hm2。     

皖南牛种质资源特性和杂交改良效果分析

[目的]研究皖南牛的种质资源特性,探讨其杂交利用效果。[方法]对皖南牛和和—皖杂交F1代牛进行了初生、6月龄、12月龄和24月龄体重和体尺性状测定。[结果]皖南牛和和—皖杂交F1代牛公母牛在0～6月龄、12～24月龄时是体重增长高峰期,利用日本和牛对皖南牛进行杂交改良,可显著改善其个体小、生长慢等不足,杂交优势明显。[结论]皖南牛是我国优良的地方品种牛之一,具有独特的遗传发育特性,亟需加以保护和开发利用,且杂交改良可能是提高其养殖效益的有效途径之一。     

Effects of supplemental protein sources during the grazing period on performance, ruminal characteristics and blood constituents in early weaned growing Wagyu steer calves

We investigated the effects of grazing and supplemental protein sources during the grazing period on growth performance, ruminal characteristics and blood constituents in 15 growing Wagyu steer calves weaned at 3 months of age. Each animal was allotted one of three treatments: (1) GSBM, soybean meal (SBM) supplemented as a protein source during a grazing period; (2) GCGM, corn gluten meal (CGM) supplemented as a protein source during a grazing period; or (3) NG, no grazing, in which steers were fed hay and GSBM concentrate only. The estimated rumen undegradable protein (RUP) concentration of CGM was higher than that of SBM. High RUP supplementation during the grazing period did not influence feed intake or growth performance. Compared with the NG treatment, the average daily gain in GSBM and GCGM calves was significantly depressed (P < 0.05). Bodyweight/withers height ratio in the NG calves tended to be greater than in the GSBM and GCGM calves. Final paunch girth/heart girth ratio in the GSBM and GCGM calves was significantly greater (P < 0.05) than in the NG calves. Supplementation with CGM did not influence ruminal ammonia nitrogen and blood constituents. These results indicate that CGM supplementation during the grazing period did not enhance the growth of Wagyu calves because the CGM diet probably did not elevate the metabolizable protein supply to the grazing calves above that of the SBM diet in our conditions.     

安秦F_1代、和秦F_1代与秦川牛生长性能比较

[目的]为探讨安秦F1代与和秦F1代与秦川牛的生长发育情况。[方法]选择安秦、和秦、秦川公牛各10头作为2个试验组和1个对照组,测定6、12、18、24月龄的空腹体重、体长、体高、胸围数据,并进行比较分析。[结果]表明,在集约化饲养条件下,6～24月龄的安秦F1代体重及各项体尺指标,均显著高于秦川牛（P〈0.05）,和...     

日本和牛与雷琼牛杂交育肥试验研究

选择20头10月龄日本和牛与雷琼牛F1代杂交牛,10头10月龄雷琼牛,以相同营养水平饲养管理方式进行20个月高强度育肥比较,分析和牛与雷琼牛F1代与雷琼牛的育肥增重效果、产肉性能。结果表明：F1杂交牛育肥期末增重显著高于雷琼牛（P〈0.01）;F1杂交牛在整个育肥期日增重均显著高于同时期的雷琼牛（P〈0．01）,其中F,杂交牛育肥3～6月日增长速度最快,雷琼牛前3个月日增长速度最快;F1杂交牛的宰前体重、胴体重、净肉重和眼肌面积均显著高于与雷琼牛（P〈0.01）,屠宰率、净肉率分别提高7．28％和6．25％。试验结果表明,日本和牛与雷琼牛杂交,F,代杂交牛经育肥后,其增重效果、屠宰性能均优于雷琼牛。     

The effects of grazing and supplemental protein concentrations during the grazing period on subsequent finishing performance and carcass quality in Japanese Black cattle steers

The effects of grazing and supplemental protein concentrations, provided during the grazing period, on subsequent finishing performance and carcass quality were investigated. This experiment was carried out using 15 Japanese Black cattle (Wagyu) steers. The steers were fed as follows: (i) grazing supplemented with moderate protein concentrate (GMP) (18% crude protein (CP); dry matter (DM) basis) before finishing, followed by feeding in a barn until slaughter; (ii) grazing supplemented with low protein concentrate (GLP) (14% CP; DM basis) before finishing, followed by feeding in the barn until slaughter; and (iii) no grazing before finishing (NG). From the end of the grazing season to the end of the growing period, the GMP and GLP steers were managed in the same way as the NG steers. All of the animals were fed the same diet in the finishing period (9 months to 28 months). None of the three treatments affected the average daily gains. For all treatments, chilled carcass weights were more than 450 kg and did not differ significantly among the groups. The longissimus muscle areas in the grazed steers were numerically larger than in those receiving the NG treatment. Fat thickness was significantly greater (P < 0.05) in the NG steers than in the grazed steers. The intramuscular fat and marbling scores were not affected in the grazed steers. In conclusion, the carcass quality of grazed steers was similar to that of the NG steers at a similar final age, and the quantity of meat in the NG steers would be less than that of the GMP and GLP steers. Therefore, spring‐born Wagyu steers should be grazed using the GLP supplement before fattening.     

Early-weaning and postweaning nutritional management affect feedlot performance, carcass merit, and the relationship of 12th-rib fat, marbling score, and feed efficiency among Angus and Wagyu heifers

Twelve 3/4 Angus (Angus) and 12 Wagyu-cross (1/2 Wagyu x 1/2 Angus) (Wagyu) heifers were weaned at 180 d of age and grazed on endophyte-infected tall fescue for 16 mo before entering the feedlot as 2-yr-olds. Twelve 3/4 Angus heifer calves and 12 Wagyu-cross heifer calves from the following year's calf crop were weaned at 142 +/- 4.1 d of age, immediately adjusted to an 80% concentrate diet, and finished as calves. All heifers were fed a common finishing diet until an estimated 50% of their respective group would grade USDA low Prime or better based on ultrasound predictions. Ultrasound measurements of s.c. and i.m. fat depots were recorded at 60-d intervals throughout the finishing period. Heifers finished as calves had higher (P = 0.02) marbling scores at any given fat thickness and gained more efficiently (P < or = 0.01) at any given marbling score than heifers finished as 2-yr-olds. Gain:feed decreased quadratically (P < or = 0.05) as 12th-rib fat thickness increased for Angus and Wagyu heifers. Gain:feed decreased linearly (P < or = 0.01) for Wagyu calves and quadratically (P < or = 0.01) for Angus calves as 12th-rib fat thickness increased. However, these differences in slope were not different (P = 0.34) as a result of breed among heifers finished as calves. Marbling score increased linearly (P < or = 0.01) as 12th-rib fat thickness increased for Angus and Wagyu heifers finished as 2-yrolds or as calves. However, Wagyu heifers, regardless of age at feedlot entry, had a higher marbling score (P < or = 0.05) at any given 12th-rib fat thickness than Angus heifers. Finishing early-weaned heifers as calves as opposed to 2-yr-olds results in i.m. fat deposition during a period of more efficient growth. Additionally, including Wagyu genetics into the breeding of early-weaned heifers finished as calves or as 2-yr-olds results in higher marbling scores at any 12th-rib fat thickness.     

不同饲养方式对涪陵水牛生长性能的影响

为了提高涪陵水牛的产肉性能，探索适合涪陵水牛的科学饲养模式，本试验研究了不同饲养方式对涪陵水牛生长性能的影响。挑选3Q头体重接近的涪陵水牛，随机分为A、B、C三组，A组采用栓系舍饲方式、B组则用半天放牧加补饲的方式、C组采取全天放牧加补饲，试验时间为3个月，通过每月末定期测定牛的体斜长、体高、胸围和管围四项指标反映生长发育情况。结果表明，半天放牧组的生长性能明显优于全天放牧组，而舍饲组优于放牧组。     

引进日本和牛冻精改良本地黄牛效果观察

[目的]观察日本和牛冻精与不同肉牛品种杂交改良效果.[方法]选择胎次、膘情和年龄接近,健康无病、饲养管理条件基本相同的经产西杂、秦杂、奶杂和本地母牛150头,随分为工、Ⅱ、Ⅲ、Ⅳ和V5组,每组30头.Ⅰ、Ⅱ、Ⅲ、Ⅳ组的120头基础母牛选用日本和牛冻精授配改良,即：日本和牛冻精x;西门塔尔x;本地黄牛杂交组合（简称和西杂组）,日本和牛冻精x;秦川x;本地黄牛杂交组合（简称和秦杂组）,日本和牛冻精x;荷斯坦奶牛x;本地黄牛杂交组合（简称和奶杂组）,日本和牛冻精x;本地黄牛（简称和杂组）,V组为本地黄牛.测量初生、6月龄、12月龄体尺、体重.[结果]表明：在初生、6月龄、12月龄体尺、体重数据中,和秦杂牛组、和西杂牛组、和奶杂牛组和和杂牛组与本地黄牛之间有显著差异（P＜0.05）;和秦杂牛组、和西杂牛组、和奶杂牛组与和杂牛组差异显著（P＜0.05）,与本地黄牛组差异极显著（P＜0.01）.[结论]和秦杂牛、和西杂牛组合可作为本市推广品种.     

限时放牧对苏尼特羔羊生长性能及主要消化器官发育的影响

为研究限时放牧对苏尼特羔羊生长性能及肉品质的影响,试验选取30只体重相近的4月龄苏尼特去势公羔作为试验动物,将其随机分成5组,每组6只。试验第Ⅰ组完全舍饲,不放牧,补饲精料500g;Ⅱ、Ⅲ、Ⅳ组放牧加补饲,放牧时间分别为2、4、8h,分别补饲精料500、250、250g;第Ⅴ组为全天放牧,放牧12h,不补饲。试验结束后羔羊全部屠宰,取相应组织样分析处理。结果表明:放牧加补饲有利于提高日增重,但放牧时间过长日增重反而降低(第Ⅳ组);第Ⅲ组羔羊的小肠长度、四胃总重量和四胃所占比例均高于其他各组,且四胃所占比例显著高于第Ⅰ组(P<0.05),其中瘤胃的发育好于其他各组。     

Growth and pubertal development of F1 bulls from Hereford, Angus, Norwegian Red, Swedish Red and White, Friesian, and Wagyu sires

The objective of the study was to characterize body growth, testicular development, and puberty from 8 to 14 mo of age in bulls (n = 120) produced by mating sires from Hereford, Angus, Norwegian Red, Swedish Red and White, Friesian, and Wagyu breeds to MARC III ((1/4) Hereford, (1/4) Angus, (1/4) Red Poll, and (1/4) Pinzgauer) cows. Traits evaluated were birth weight, weaning weight (at 215 d), yearling weight, ADG from 8 to 14 mo of age, paired testicular volume growth from 8 to 14 mo of age, age at puberty (determined by production of 50 x 10(6) sperm with 10% motility), age at freezable semen (determined by production of 500 x 10(6) sperm with 50% motility), and, at 15 mo of age, paired testicular weight and daily sperm production per testis pair. There was an effect of sire breed (P = 0.03) for age at puberty; animals with Wagyu and Swedish Red and White inheritance reached puberty at a later date (302 and 302 d of age, respectively) compared with Angus-sired bulls (268 d). Age at puberty for Hereford-, Norwegian Red-, and Friesian-sired bulls was 270, 271, and 278 d, respectively. Differences in BW were observed (P = 0.03) at birth; bulls with Hereford and Friesian were heavier at birth (43 and 41 kg, respectively) compared with those with Norwegian Red, Swedish Red and White, and Wagyu inheritance (39, 38, and 38 kg, respectively). Differences in BW were also observed at 1 yr of age (P = 0.001), where the heaviest animals were those sired by Angus (450 kg), whereas the lightest animals were those sired by Wagyu (403 kg). Bulls with Wagyu inheritance had the lowest (P = 0.04) ADG (1.12 kg/d) compared with bulls with inheritance from Hereford (1.22 kg/d), Angus (1.28 kg/d), Norwegian Red (1.24 kg/d), Swedish Red and White (1.25 kg/d), and Friesian (1.27 kg/d). Differences in scrotal growth rate were not significant (P = 0.99). They ranged from 1.95 in Angus-sired to 1.66 cm3/d in Wagyu-sired bulls. There were no differences (P = 0.80) for age at freezable semen (335 +/- 10 d). At slaughter (15 mo of age), there were no differences (P = 0.62) for paired testicular weight (603 +/- 28 g) and daily sperm production (10.6 x 10(9) +/- 0.9 x 10(9) per testis pair). Growth of bulls with Wagyu inheritance was slower, and bulls with Wagyu or Scandinavian inheritance reach puberty at an older age than bulls with Angus inheritance.