贵州喀斯特地区胚胎移植安格斯牛生长性能初探

本研究以贵州喀斯特地区胚胎移植所产的17头公犊,25头母犊共42头安格斯牛为材料,对其初生至12月龄的体重、体尺等生长发育指标进行了测定,并与原产地同龄段安格斯牛和本地黎平黄牛的相应生长发育指标进行比较,以确定胚胎移植安格斯牛在本地区的适应性.结果表明,胚移犊牛基本适应当地自然条件和饲养管理条件,生长性能较本地黎平黄牛明显高;胚移公犊各年龄段体重明显低于原产地同龄段公犊,甚至低于胚移母犊;胚移牛不同年龄阶段日增重,公、母犊均以3月龄以前最快,3～6月龄最差.     

安格斯牛胚胎移植的试验研究

以沈阳市奉东优良畜禽繁育基地饲养的纯种安格斯牛为供体,以基地和东陵区农户饲养的杂种牛为受体,进行胚胎移植,共获得169枚胚胎,其中可移植胚胎95枚,平均每头（次）获得可用胚胎数5．9枚。将13枚鲜胚和16枚冻胚移植给同期发情的受体牛,结果为鲜胚的产犊率为38．5％（5／13）,冻胚为43．8%（7／16）;将61枚冻胚移植给自然发情的受体牛时,产犊率为42．6％（26／61）;冻胚的总产犊率为42．9％（33／77）。     

胚胎移植所产安格斯牛在湖北地区的适应性研究

对湖北省胚胎移植所产安格斯牛进行了观察、记录和测定,其体尺发育良好,日增重0.5￣1岁时最高,生理指标均在正常值范围内,公牛所产精液达到GB4143-84标准要求,大多数母牛繁殖机能正常。但也发现其生长发育过程中生长速度转慢、易患寄生虫疾病、其体形凹背和垂腹的比例较大、母牛繁殖性能较低等问题。整体上胚胎移植的安格斯牛对湖北地区的环境条件是适应的。     

胚胎移植安格斯牛血统关系的分子遗传检测

胚胎移植牛的血统界定,在生产中有十分重要的意义。本研究采用RAPD方法对25头胚胎移植的安格斯肉犊牛进行了分析,结果表明RAPD可以较好的将这25头胚移牛的血统关系反应出来,其聚类的结果与其系谱基本一致。     

红安格斯牛超数排卵和胚胎移植受体同期发情处理

选择100头红安格斯母牛使用2种超数排卵处理方案,有效超排供体母牛77头。对受体牛采用3种方案进行同期发情处理。结果表明:育成母牛和经产母牛平均回收胚胎数分别为8.45、9.23枚(P>0.05),平均回收可用胚胎数分别为6.33、7.02枚(P>0.05);2种超排方案均取得较好的效果,超排方案1和方案2分别回收胚胎数为10.10、7.63枚,回收可用胚胎数为6.62、6.51枚。受体同期发情处理一次PG法、二次PG法及CIDR+PG法,同期发情率分别为71.19%、74.44%和77.63%(P>0.05),发情受体利用率分别为66.67%、64.93%及69.49%(P>0.05),胚胎移植妊娠率分别为50.00%、55.17%和56.10%(P>0.05),与自然发情受体利用率及胚胎移植妊娠率无显著性差异。     

发酵稻草对安格斯牛生长性能、屠宰性能、血清生化指标及肉品质的影响

本试验旨在研究发酵稻草对安格斯牛生长性能、屠宰性能、血清生化指标及肉品质的影响。选择体重[（561.23±7.09） kg]相近、体况良好、23月龄左右的安格斯阉牛30头,随机分为3组,每组10个重复,每个重复1头。对照组饲粮中添加10.23%稻草,Ⅰ组饲粮中添加10.00%发酵稻草,Ⅱ组饲粮中添加20.00%发酵稻草,3组饲粮营养水平基本一致。预试期15 d,正试期165 d。结果表明;1）Ⅰ组和Ⅱ组的平均日增重、平均采食量和终末腹围显著高于对照组（P<0.05）,料重比显著低于对照组（P<0.05）。与对照组相比,Ⅰ组和Ⅱ组的养殖效益分别提高了7.60%和14.94%。2）Ⅰ组和Ⅱ组的血清球蛋白和总蛋白含量显著高于对照组（P<0.05）。3）各组之间屠宰性能指标差异不显著（P>0.05）。4）Ⅰ组和Ⅱ组的肌肉肉色黄度（b*）值和粗脂肪含量显著高于对照组（P<0.05）,肌肉剪切力显著低于对照组（P<0.05）。Ⅰ组和Ⅱ组的肌肉饱和脂肪酸（SFA）含量均低于对照组（P>0.05）,肌肉单不饱和脂肪酸（MUFA）和多不饱和脂肪酸（PUFA）含量...     

黑安格斯牛超数排卵试验效果分析

[目的]为了验证黑安格斯牛超数排卵设计方案的可行性。[方法]超数排卵方案采用CIDR＋GnRH＋VADE＋FSH＋PG的方法。[结果]本次试验获得平均可用胚胎数7．6枚／头,可用胚胎率为82％。[结论]该试验方案效果显著,可以应用于黑安格斯牛超数排卵处理。     

复合菌发酵稻草对安格斯牛生长性能、瘤胃发酵参数及菌群结构的影响

本试验旨在研究复合菌发酵稻草对安格斯牛生长性能、瘤胃发酵参数以及菌群结构的影响.选择14月龄左右、体重[(390.47±50.14)kg]相近的健康安格斯牛20头,随机分为2组,每组10个重复,每个重复1头牛.稻草组(RS组)饲喂稻草+玉米青贮+精料全混合日粮,发酵稻草组(FRS组)饲喂发酵稻草+玉米青贮+精料全混合日...     

固原市安格斯肉牛的胚胎移植效果

[目的]观察固原市安格斯肉牛的胚胎移植效果。[方法]利用非手术移植方法,把安格斯牛冷冻胚胎移植入受体母牛。[结果]把100头安格斯牛冷冻胚胎移植到西门塔尔牛、安格斯牛、秦川牛品种的受体母牛,其移植妊娠率为45%。[结论]固原市安格斯牛的胚胎移植已经获得了较好的效果,但还需要进一步提高移植妊娠率。     

Diagnosis and control of pseudolipidosis of angus calves

Abstract

Extract

Sir,—Pseudolipidosis, a nervous disease of Angus calves, characterized by head tremor, ataxia and inco-ordination was first described in Australia by Whittem and Walker (1957 Whittem, J. H. and Walker, D. 1957. “Neuronopathy” and “Pseudolipidosis” in Aberdeen Angus calves. J. Path. Bact., 74: 281–288.  [Google Scholar]), and was diagnosed shortly afterwards in New Zealand (W. J. Hartley, pers. comm.). In recent years, a growing awareness by breeders and veterinarians of its widespread occurrence has stimulated interest in its control and eradication. Procedures necessary for this must be based on a knowledge of the disease's aetiology and pathogenesis. Long assumed to be an inherited disease because of circumstantial evidence and its pathological similarity to certain of the inherited storage diseases of children, it was not until recently that there was any experimental evidence to support this hypothesis. As a result of this new evidence, the New Zealand Angus Society has recommended to their members procedures that should afford some measure of control until more effective methods can be evolved. Consequently, although our studies are incomplete, it is desirable that information on clinical signs, means of diagnosis, inheritance and the breed society's recommended means of control should also be available to the veterinary profession.     

Effects of dam nutrition on growth and reproductive performance of heifer calves

A 3-yr study was conducted with heifers (n = 170) whose dams were used in a 2 x 2 factorial arrangement of treatments to determine the effects of late gestation (LG) or early lactation (EL) dam nutrition on subsequent heifer growth and reproduction. In LG, cows received 0.45 kg/d of a 42% CP supplement (PS) or no supplement (NS) while grazing dormant Sandhills range. During EL, cows from each late gestational treatment were fed cool-season grass hay or grazed sub-irrigated meadow. Cows were managed as a single herd for the remainder of the year. Birth date and birth weight of heifer calves were not affected (P > 0.10) by dam nutrition. Meadow grazing and PS increased (P = 0.02; P = 0.07) heifer 205-d BW vs. feeding hay and NS, respectively. Weight at prebreeding and pregnancy diagnosis were greater (P < 0.04) for heifers from PS dams but were unaffected by EL nutrition (P > 0.10). There was no effect (P > 0.10) of LG or EL dam nutrition on age at puberty or the percentage of heifers cycling before breeding. There was no difference (P > 0.10) in pregnancy rates due to EL treatment. Pregnancy rates were greater (P = 0.05) for heifers from PS dams, and a greater proportion (P = 0.005) of heifers from PS dams calved in the first 21 d of the heifers' first calving season. Nutrition of the dams did not influence (P < 0.10) heifers' average calving date, calving difficulty, and calf birth weight during the initial calving season. Weight at the beginning of the second breeding season was greater (P = 0.005) for heifers from PS dams but was not affected by maternal nutrition during EL (P > 0.10). Dam nutrition did not affect (P > 0.10) heifer ADG or G:F ratio. Heifers from PS dams had greater DMI (P = 0.09) and residual feed intake (P = 0.07) than heifers from NS cows if their dams were fed hay during EL but not if their dams grazed meadows. Heifers born to PS cows were heavier at weaning, prebreeding, first pregnancy diagnosis, and before their second breeding season. Heifers from cows that grazed meadows during EL were heavier at weaning but not postweaning. Despite similar ages at puberty and similar proportions of heifers cycling before the breeding season, a greater proportion of heifers from PS dams calved in the first 21 d of the heifers' first calving season, and pregnancy rates were greater compared with heifers from NS dams. Collectively, these results provide evidence of a fetal programming effect on heifer postweaning BW and fertility.     

Effects of supplementation with cellooligosaccharides on growth performance of weaned calves on pasture

We conducted two feeding experiments to evaluate the effects of cellooligosaccharide (CE) supplementation on growth performance in grazing beef calves. Calf sex and age and duration of the experimental period differed between the experiments. Experiment 1 (10 weeks) used 5.6‐month‐old castrated males; Experiment 2 (13 weeks) used 3.9‐month‐old females. Eight Japanese Black calves were assigned to either a control group (CON) or an experimental group (CE) fed CE at a rate of 10 g/day mixed with concentrate. Calves were stocked in fields in which Kentucky bluegrass was dominant. In both experiments, average daily gain tended to be greater in CE than in CON, especially in late stages of experiments, but no significant differences in body weight changes were observed. In Experiment 2, final heart girth was larger in CE than in CON calves. We monitored rumen microbial community composition in Experiment 2 and found increases in fibrolytic bacteria and methanogenic archaea in CE calves, but the overall microbial composition did not differ between the groups. Our results suggest that supplementation with CE may positively affect growth performance in weaned calves on pasture, but longer‐term CE supplementation may be required to exhibit the effect.     

饲喂大豆异黄酮对荷斯坦犊牛生长性能及腹泻的影响

为研究饲喂不同浓度大豆异黄酮(soy isoflavone, SIF)对荷斯坦犊牛生长性能及腹泻的影响,试验采用单因素随机分组设计将40头体况良好、体重相近的(30±10)日龄荷斯坦犊牛分为4组:CON组,TGⅠ、Ⅱ、Ⅲ组,每组10头。CON组饲喂3×2 L/d全脂酸化乳,开食料自由采食;TGⅠ、Ⅱ、Ⅲ组分别在对照组饲喂的基础上添加100、300、600 mg/d SIF。预试阶段7 d及正试阶段60 d。于正试阶段0、20、40、60 d时称(测)量犊牛体重、体尺并计算日增重,每日进行犊牛粪便评分,每周统计腹泻率和腹泻频率。结果表明:试验组日增重在试验全期及各期均高于CON组且TGⅢ组日增重最高。试验组腹泻率和腹泻频率在试验全期及各期均不高于CON组且TGⅢ组腹泻率和腹泻频率最低。综上所述可得结论:饲喂大豆异黄酮有提高荷斯坦犊牛增重促进生长的作用,且饲喂浓度为600 mg/d饲喂时间在40 d以上时效果最佳。饲喂大豆异黄酮有降低犊牛腹泻率的作用,且饲喂浓度为600 mg/d时效果最佳。     

复合酸度调控剂对犊牛生长性能、血气指标的影响

探讨代乳粉中添加复合酸度调控剂对0～3月龄犊牛生长性能、血气指标的影响。试验分为对照组和试验组,分别饲喂乳液pH值为6.2和5.0的代乳粉。每个处理6头犊牛,分别在试验开始后的0、14、28、42、56d测定每头犊牛的体重、体尺,每日记录每头犊牛代乳粉和开食料供料量和剩料量,观察每头犊牛的粪便形态和评分,并分别在0、14、42d采血测定血气指标。试验数据显示:与对照组相比,试验组犊牛各阶段的平均日增重有所提高,其中0～14、14～28、28～42、42～56d分别提高了5.6%、45.9%(P<0.05)、11.9%、5.8%;试验全期两组间平均日采食量、饲料转化率差异皆不显著(P>0.05);全期腹泻率试验组比对照组降低了13.9%,但差异不显著(P>0.05);28d体长指数试验组低于对照组(P<0.05)。试验开始(0d)和饲喂42d时各组间犊牛血气指标皆无差异(P>0.05);饲喂14d时试验组血液的pH值(P<0.05)、氧饱和度(P<0.05)、氧气分压、实际剩余碱储、标准碳酸氢盐浓度皆高于对照组,而二氧化碳分压显著低于对照组(P<0.05)。结果表明,在代乳粉中添加复合酸度调控剂后28d前对犊牛产生了一定作用,可提高14～28d阶段犊牛日增重,降低28d体长指数,并有降低腹泻率的趋势;犊牛血液的pH值、SO2升高而PCO2降低。     

Effect of birth date on growth performance of calves of seasonally-bred range cattle

SUMMARY: This study was undertaken to investigate the relationship between date of birth and growth performance of calves born to seasonally-bred range beef cows. Late-born calves exhibited an apparent superiority in preweaning growth over that of their early-born counterparts. This was attributed to a positive residual effect of maternal environment arising from the fact that calves born late were those whose dams had a substantial proportion of the critical last trimester of the gestation period in a favourable season. This advantage soon disappeared and early-born calves gained more weight and at a faster rate between 90 days and weaning. A combination of the effect of weaning stress and unfavourable nutritional environment in the immediate postweaning period had a check on calf growth but late born calves suffered most. It was concluded that, in this environment, nutrition was most limiting to calf growth between weaning and 12 months of age and it was during this period that a clear advantage of early birth of calves appeared; A 1 day delay in BD was associated with a 9.1 kg (P < .01) decrease in net weight change in this period. However, due to compensatory growth, the corresponding figure for the 12 months to 18 months period was an increase of 11.6 kg (P < .01) in weight change. In terms of actual postweaning weights (not age-adjusted), early BD was superior to late BD at all ages except at 18 month. A 1 day delay in BD was associated with a .7 kg reduction (P < .01) in liveweight between 90 days and weaning, a 6.7 kg reduction (P < .01) in actual weaning weight, a 6.8 kg reduction (P < .01) in actual 12 months liveweight, and a non significant (P > .05) 0.7 kg reduction in actual 18 months liveweight. Under seasonal breeding and group management of calves, all animals from a calf crop are expected to go to market at the same time, thereby rendering age-adjustment of liveweights irrelevant. However, the sale of late calves could be delayed by a few months to take advantage of the rainy season and to exploit compensatory growth. The benefit of this practice should, however, be weighed against both the direct cost (of feeding, veterinary care, labour and so on) and the indirect cost - the competition factor -introduced on the next calf crop. ZUSAMMENFASSUNG: Beziehung zwischen Geburtsdatum und Wachstumsleistung von K?lbern saisongedeckter Fleischrinder Sp?tgeborene K?lber zeigten eine scheinbare überlegenheit im Saugperiodenwachstum, was den positiven Restwirkungen maternaler Umwelt zugeschrieben wird, die auf günstige Umwelteinflüsse w?hrend des letzten, dann regenreichen Trimesters der Tr?chtigkeitsperiode zurückzuführen sind. Dieser Vorteil ist bald verschwunden, und frühgeborene K?lber hatten ein rascheres Wachstum zwischen 90 Tagen und dem Absetzen. Eine Kombination von Absetzstre? und ungünstiger Ern?hrungssituation unmittelbar nach dem Absetzen bremste das Jungtierwachstum, wobei sp?tgeborene K?lber den meisten Schaden zeigten. In der gegebenen Umwelt hat mangelnde Ern?hrung den st?rksten begrenzenden Einflu? auf Wachstum zwischen Absetzen und J?hrlingsalter, so da? sich in dieser Periode der Vorteil von frühen Geburten zeigte. Eine Verz?gerung von 1 Tag bei der Geburtszeit führte zu 9,1 kg Verminderung des Nettogewichts-Zuwachses in dieser Periode. Aufgrund kompensatorischen Wachstums ?nderte sich das zwischen 12 und 18 Monaten auf plus 11,6 kg Zuwachs. In bezug auf Jungtiergewichte (nicht alterskorrigiert) waren Tiere mit frühem Geburtsdatum in allen Altersklassen, au?er bei 18 Monaten, überlegen. Eine Verz?gerung von 1 Tag im Geburtsdatum war verbunden mit 0,7 kg Reduktion im K?rpergewichtszuwachs zwischen 90 Tagen und Absetzen, mit einer 6,7 kg Reduktion im Absatzgewicht und 6,8 kg im J?hrlingsgewicht. Das 18 Monate Gewicht war insignifikant um 0,7 kg reduziert. Unter saisonaler Zucht und Management gehen alle Tiere zur selben Zeit auf den Markt, so da? Alterskorrekturen irrelevant sind. Allerdings k?nnte der Verkauf sp?tgeborener K?lber um einige Monate verz?gert werden, um die Vorteile der Regenzeit und des damit verbundenen kompensatorischen Wachstums auszunutzen. Vorteile einer solchen Praxis aber sollten sowohl gegen die direkten (Futter, Veterin?re, Arbeit usw). wie auch gegen indirekte Kosten (Wettbewerb durch die n?chsten K?lber) balanciert werden.     

鸡胚给养氨基酸对肉仔鸡孵化率和胚胎生长的影响

本试验将90枚孵化第18天的落盘肉仔鸡胚蛋随机分为3组,分别向羊膜腔注射0.5mL复合氨基酸溶液、0.5mL生理盐水和不注射(对照组),研究对孵化率和后期胚胎生长的影响。结果显示:各处理组间的孵化率和出壳体重无显著差异(P>0.05),但出壳重与第18天胚蛋重的比值有显著差异(P<0.05),注射氨基酸组比对照组增加2.3%。这些结果表明鸡胚给养氨基酸可有效增加肉鸡出壳重。     

犊牛生产体系和断奶后的管理对其生长性能的影响

文章旨在评估犊牛生产系统和断奶后管理对其生长性能和胴体特征的影响。试验采用2×2因子设计,两个生产系统(在玉米秸秆上饲养和在干燥环境饲养),两个断奶后的管理(直接育肥和采用生长-育肥两阶段饲养)。结果显示:与冬季在干燥环境饲养的牛相比,冬季在玉米秸秆上过冬的犊牛初始体重较轻(P <0.05)。同时,冬季在干燥环境下饲养的犊牛较在玉米秸秆上过冬的犊牛日增重显著提高(P <0.05)。前期在玉米秸秆上过冬的犊牛在生长-育肥期的初始体重显著低于在干燥环境饲养犊牛(P <0.05)。但在玉米秸秆上过冬的犊牛较干燥环境饲养的犊牛存在代偿性反应特征,表现为日增重和饲料报酬显著提高(P <0.05)。在评价断奶后管理对生长性能的影响时,生长-育肥期犊牛较育肥期犊牛初始体重、末重和干物质摄入量显著提高(P <0.05)。但与生长-育肥期犊牛相比,育肥期犊牛日增重和饲料报酬显著提高(P <0.05)。断奶后的管理和生产体系对大理石纹的影响具有显著交互效应(P <0.05)。在玉米秸秆上过冬的生长-育肥组较其他组显著提高了大理石纹评分(P <0.05)。结论:与断奶后直接饲喂育肥期饲料的犊牛相比,采用生长-育肥两阶段饲喂方式的犊牛胴体重量显著提高。然而,直接饲喂育肥料的犊牛饲料报酬和日增重均提高,两阶段饲喂方式的犊牛在经济收益上无显著差异。