产犊季节和胎次对测定奶牛日泌乳性能的影响

[目的]通过研究产犊季节、胎次对奶牛测定日泌乳性能的影响,以期为指导日粮配方调整、增加牛奶产量和提升原料奶质量提供科学依据。[方法]采集江苏某奶牛场2012年度408头奶牛共3012条生产性能测定记录,用线性模型分析产犊季节和胎次对测定日产奶量、乳脂率、乳蛋白率、脂蛋比、305d产奶量及体细胞评分的影响进行分析。[结果]表明：不同产犊季节对测定日产奶量和305d产奶量的影响极显著（P〈0．01）,对乳脂率、乳蛋白率、脂蛋比无显著影响;不同胎次除对乳脂率影响显著外（P〈0．05）,对其它奶牛泌乳性能及体细胞评分均影响极显著（P〈0．01）。[结论]夏、秋两季产犊奶牛的305d产奶量高;2～3胎产犊奶牛的泌乳性能较佳,随着胎次的增加,特别是5胎及以后,泌乳性能的各项指标都有不同程度的降低。     

影响奶牛产犊间隔的因素分析

对江苏省徐州市某奶牛场约800头荷斯坦奶牛1998到1999年产犊间隔与产犊季节、产奶量、产犊胎次、犊牛初生重、犊牛性别等基础资料进行统计分析,结果表明:产犊季节对产犊间隔有极显著的影响(P<0.01);奶牛的产奶量对产犊间隔也有极显著的影响(P<0.01);产犊胎次、犊牛初生重及犊牛性别对产犊间隔无显著影响(P>0.05)。     

中国荷斯坦牛青年初产年龄和成年母牛产犊间隔遗传参数估计

本研究旨在估计河南省青年牛初次产犊年龄与成年母牛产犊间隔遗传参数。收集河南省17个牧场2008—2017年14406头青年牛的初次产犊年龄记录与8912头成年母牛的产犊间隔记录,使用DMU软件DMU_AI模块采用AI-REML结合EM算法的动物模型估计性状遗传参数。动物模型中的固定效应包括出生年季、产犊年季和牧场效应,产犊间隔性状动物模型还包括胎次效应;随机效应包括加性效应和残差效应。结果表明:青年牛初次产犊年龄的遗传力为0.21、成年母牛产犊间隔性状遗传力为0.05,与相似研究结果相近,为制定区域性、精细化的育种目标提供理论参考。     

产犊季节、胎次及牛场对荷斯坦牛泌乳性能的影响

[目的]研究产犊季节、胎次及不同牛场对奶牛泌乳性能的影响情况,以期为提高奶牛的泌乳性能及牛奶质量提供可靠的理论依据。[方法]收集3个千头以上奶牛场共8 872次相关信息,用多因素方差分析法分析产犊季节、胎次和牛场对泌乳天数、305d校正奶量、305d脂肪产量、305d蛋白产量和全泌乳期产奶量5个泌乳性能的影响进行分析。[结果]不同产犊季节、胎次和牛场都极显著影响奶牛的5项泌乳性能(P<0.01)。夏季和秋季产犊奶牛的泌乳性能较为理想。夏季产犊奶牛的泌乳天数和全泌乳期产奶量最高,其他三个泌乳性能都位居第二;秋季产犊奶牛的305d校正奶量、脂肪产量和蛋白产量都显著高于其他三个季节(P<0.05),泌乳天数和全泌乳期产奶量也仅次于夏季。头胎牛的各项泌乳性能都显著高于其他胎次的奶牛(P<0.05),其次为2胎产犊奶牛。随着胎次的增加,泌乳性能的各项指标都有不同程度的降低。除了泌乳天数之外,A牛场的各项泌乳性能都最佳,且显著高于B、C两个奶牛场(P<0.05)。[结论]在饲养条件良好的情况下,本研究中三个牛场的奶牛适宜在夏、秋两个季节产犊,此时泌乳性能较好;此外,头胎产犊奶牛的泌乳性能在各胎次中最高。     

温带气候条件下胎次、季节和哺乳期对母猪繁殖性能的影响

利用最小二乘法对温带气候条件下874窝杜洛克和659窝大约克母猪的繁殖性状数据进行统计分析。结果表明:胎次、季节对杜洛克和大约克母猪的断奶再发情间隔、产仔数、21日龄窝重等繁殖性状影响显著(P<0.05);哺乳期对杜洛克和大约克母猪的断奶再发情间隔影响显著(P<0.05)。母猪1~7胎繁殖性状呈现先升高后降低的趋势,随着哺乳期的延长母猪断奶再发情间隔先减少后增加,夏季高温高湿对母猪产生热应激,影响其生长性能的发挥。在生产中,加强对初产和六胎以上的母猪饲养管理,及时淘汰老龄母猪,在夏季做好母猪的防暑降温等工作,推荐采用21~28d断奶。     

胎次和泌乳阶段对荷斯坦奶牛血液乳成分前体物及泌乳相关激素含量的影响

本文旨在研究胎次和泌乳阶段对荷斯坦奶牛血液乳成分前体物及泌乳相关激素含量的影响。选取不同泌乳阶段的1~4胎奶牛60头荷斯坦奶牛饲喂相同全混合日粮,每15 d采集血液。血液检测参数有葡萄糖(GLU)、甘油三酯(TG)、非酯化脂肪酸(NEFA)、β-羟丁酸(BHBA)、总氨基酸(T-AA)5种乳成分合成前体物及甲状腺素(T4)、生长激素(GH)、皮质醇(COR)、胰岛素(INS)、催乳素(PRL)、孕酮(PRG)6种激素的含量。利用SAS 9.2中Proc Univeriate程序进行正态分布检验,利用Proc Mixed线性模型评估胎次、泌乳阶段的固定效应。结果表明:1)胎次可显著影响泌乳奶牛血液INS及PRL含量(P0.05),而对血液COR、GH、PRG、T4及5个乳成分前体物含量无显著影响(P0.05)。2)随着泌乳时间延长,血液GLU含量逐渐递增,且泌乳早期(0~21 d)显著低于其他泌乳阶段(P0.05),而泌乳早期血液BHBA和NEFA含量显著高于其他泌乳阶段(P0.05),同时血液T-AA含量在泌乳中期(22~100 d)显著高于其他泌乳阶段(P0.05);泌乳阶段对奶牛血液COR、GH、PRG、T4和INS含量均有显著的影响(P0.05),但对血液PRL含量无显著影响(P0.05),其中泌乳前期COR含量显著高于泌乳中期和后期(201~305 d)(P0.05),而泌乳后期的GH、PRG和T4含量均较高。本方法能提高利用生化检测指标评估泌乳荷斯坦奶牛代谢状态的准确性,可以作为奶牛养殖者监测奶牛健康状态的工具。     

季节变化对奶牛日粮营养物质消化率的影响

环境温度变化明显影响奶牛日粮营养物质的消化率,试验以8头泌乳奶牛分别在春季、夏季进行消化试验,以比较季节温度变化对奶牛日粮营养物质表观消化率的影响。结果表明:春季奶牛日粮粗蛋白质、中性洗涤纤维、酸性洗涤纤维的表观消化率分别为57.79%、45.77%和39.08%,相应夏季的表观消化率则为68.3%、67.81%和51.09%,夏季的营养物质表观消化率显著高于春季(P<0.05)。     

产后20天应用氯前列烯醇对分娩期和产后期异常奶牛繁殖指标的影响

本试验选用276头高产中国荷斯坦牛为研究对象,其中120头初产奶牛和156头经产奶牛均表现为分娩期异常或产后期异常,如难产、胎衣不下、双胎难产、早产或子宫感染。试验牛被分为处理组与对照组。处理组在产后20d间隔811连续两次皮下注射氯前列烯醇（0.4mg/次）,对照组注射4．0mL灭菌生理盐水。然后观察其首次发情的时间、适合第一次人工授精的时间、首次授精妊娠率、150d妊娠率、产后的空怀天数、重复配种奶牛的比例和每头牛的授精次数。结果表明,产后应用前列腺素对产后首次发情的时间和产后首次人工授精的时间没有影响,但处理组奶牛首次人工授精的妊娠率明显升高,这在头胎牛更为明显;产后应用氯前列烯醇可明显减少平均授精次数、缩短产后空怀时间、增加产后150d泌乳奶牛的妊娠率、降低产犊后重复配种率。     

胎次对荷斯坦牛产奶量及乳脂率的影响

为了探讨胎次对荷斯坦奶牛产奶量和乳脂率的影响,本试验选用67头健康无病的荷斯坦奶牛,研究了胎次对荷斯坦牛305 d产奶量及乳脂率的影响,并分析胎次与产奶量及乳脂率的相关性.结果表明：胎次对奶牛产奶量的影响显著（P＜0.05）,而未对乳脂率产生显著影响（P＞0.05）.由相关分析可知,胎次和产奶量呈极显著正相关（r=0.452,P＜0.01）,胎次与乳脂率的相关不显著（r＝0.056,P＞0.05）.     

应用PMSG、氯前列烯醇药物提高奶牛场奶牛繁殖效率及缩短奶牛产犊间隔

试验建立了有效的奶牛卵巢疾病治疗技术,探讨了影响奶牛场奶牛繁殖率的若干因素。试验结果表明:PG子宫内给药组, 0. 3mg剂量同 0. 2, 0. 4mg剂量相比,发情有效头数差异虽不显著(P>0.05),但效果好于 0. 2, 0. 4mg剂量;PG肌肉注射组,一次肌肉注射 0. 6mg剂量可有效地诱导卵巢持久黄体、黄体囊肿的奶牛发情,同肌肉注射 0. 4mg剂量相比,发情效果明显地好于 0. 4mg组,且差异显著(P<0.05),同二次肌肉注射氯前列烯醇发情有效头数差异不显著。对卵巢静止和卵巢机能不全所致的乏情母牛,PMSG只注射一次即能得到预期效果。     

影响奶牛产犊间隔的因素分析

对西宁某奶牛场1993—2000年中国荷斯坦奶牛的配种、产犊记录和产奶量记录进行了统计分析，结果表明：胎次和产犊季节对奶牛产犊间隔没有显著影响(P＞0．05)；产奶量在6000kg以上奶牛的产犊间隔板显著长于4000kg以下的奶牛(P＜0．01)，显著长于产奶量在4000—4999kg奶牛的产犊间隔(P＜0．05)。     

Factors Affecting Fertility According to the Postpartum Period in Crossbred Dual-Purpose Suckling Cows in the Tropics

To determine the relationship between first service conception rate (FSC) and the postpartum period (PP), 6160 calvings from 2250 crossbred dual-purpose cows were analysed. The effects of breed predominance (BT: Bos taurus and BI: Bos indicus), season of service (dry, intermediate and humid), parity (1 or 2 and more), agroecological region (Sub-humid and Dry Tropical Forest) and milk production were studied. The postpartum period was grouped according to the calving–first service interval as G1 ≤ 60 days (n = 1889); G2 > 60 ≤ 90 days (n = 1436); G3 > 90 ≤ 120 days (n = 1030); and G4 > 120 days (n = 1805). Data were analysed by chi-squared test. The overall mean for FSC was 58.2% and was lower in G1 (p < 0.01). All PP showed a breed effect on FSC, with mean values of 61.6% and 53.3% for BI and BT, respectively. Season of service also affected FSC, which was significantly lower during the humid period: 51.2% versus 57.4% and 61.5% for the intermediate and dry periods (p < 0.01), respectively. Parity and environmental effects were not observed on FSC. Levels of milk yield did influence the FSC, which decreased from 66.7% and 61.0% for milk yields of < 1500 kg and between 1501 and 2000 kg to 46.0% in milk yields > 2000 kg (p < 0.01).     

季节与奶牛疾病关系的探讨

本文根据膛师院附属兽医院（１９８３－１９９３）临床病例资料的和安微省部分奶牛场的调查资料，试就季节对奶牛乳房炎，支气管炎及支气管肺炎，奶牛流行热，传染性角膜炎。结果炎和奶牛焦虫病的影响进行分析探讨，以利减少和预防奶牛疾病。     

Reproduction and Lactational Performance of Cattle in a Smallholder Dairy System in Zimbabwe

A study was conducted in two adjacent locations. Nharira (communal) and Lancashire (small-scale commercial) farming areas in Zimbabwe to characterize the breeds and evaluate the reproductive and lactation performance of dairy cattle under smallholder management. The types of cows identified were Friesian, Jersey and Red Dane, and an indigenous Sanga breed called the Mashona and its crossbreds. Both sectors used more exotic and crossbred cows than indigenous cows. The mean monthly weights of the dairy cows were higher in Lancashire than in Nharira and the calving intervals were longer in Nharira than in Lancashire. The mean age at first calving was higher and the mean total lactation yields were greater in Nharira than in Lancashire, but the mean 305-day lactation yields were not significantly different. The mean lactation lengths were longer for the cows from Nharira. It was concluded that the reproductive and lactation performances were low. The calving intervals were extended, probably owing to suboptimal nutrition and heat stress, particularly during the dry season, and to poor management practices, such as delayed mating due to the poor availability of bulls.     

两广地区带犊母牛体系建立之浅谈

带犊母牛体系的建立在肉牛产业链中具有非常重要的意义。本文就该体系中种牛的选育、母牛产犊率和犊牛断奶体重的主要管理作一简单概述。     

健宫散对产后子宫炎奶牛生殖激素的影响

试验旨在研究中药复方健宫散对子宫炎奶牛生殖激素雌二醇(E2)、促卵泡生成素(FSH)、黄体生成素(LH)的影响。选取年龄、体况评分(BCS)和胎次相近的18头奶牛,按临床症状、阴道分泌物的性状、B超检查分为患病组(患子宫炎不治疗)、正常组(未患子宫炎)和治疗组(患子宫炎治疗),每组6头。治疗组每日灌服中药健宫散400 g/头,患病组与正常组灌服生理盐水400 g/头。灌药期为一个疗程(7 d)。分别于用药前、用药中、停药后1、4、7、11、15、20 d采集血液,检测3组奶牛E2、FSH、LH指标。结果表明:中药复方健宫散治疗后E2、FSH、LH都显著上升,E2出现2个峰值,在停药后1 d达到最高峰,停药后7 d达到第2个高峰;FSH在停药后4 d达到高峰;LH在用药中达到高峰。其中E2、FSH、LH的峰值显著高于正常组、患病组,而LH的峰值比正常组、患病组峰值提前。本试验条件下,中药复方健宫散可以促进性激素分泌,调节性激素代谢,从而达到预防和治疗子宫炎效果。     

Survival Analysis of Calves and Reproductive Performance of Cows in Commercial Dairy Farms in and Around Addis Ababa,Ethiopia

A study was conducted at five locations to determine the survival rate of calves and to estimate the performance level of improved dairy cows under commercialized farming systems in Ethiopia. Seven hundred and one calves born from 1997 to 1999, and 797 cows were included in the study. Cumulative calf/heifer survival at 360, 540 and 720 days was 80%, 76% and 70%, respectively. Number of services per conception averaged 2 while mean age at first service and days open were 850+/-18 and 192+/-11 days, respectively. Calf survival, days open and age at first service were significantly affected by breed and management factors (p <0.05), whereas parity significantly affected the number of services per conception and days open. There was a tendency towards improved performance over the years. This was especially so for calf survival and days open. Clearly, all the traits measured varied among study farms, indicating that substantial improvement can be achieved through better management. This paper describes these individual traits of improved dairy breeds under commercialized farming systems in Ethiopia.     

中药复方灌注液对奶牛急性子宫内膜炎临床疗效观察

为了考察中药复方灌注液对奶牛子宫内膜炎自然病例的临床治疗效果,将确诊患有急性子宫内膜炎的病牛40头,随机分为5组(A组~E组),每组8头,其中A、B、C组分别为中药复方灌注液高、中、低剂量组,分别子宫内灌注中药复方灌注液150、100、50mL/次,隔天1次,连用3次;D组为阳性药物对照组,子宫内灌注双黄连注射液100mL/次,隔天1次,连用3次;E组为疾病对照组,不给药,另选择临床健康奶牛8头作为健康对照组(F组),不给药。结果表明,中药复方灌注液能显著降低急性子宫内膜炎病牛子宫颈口黏液白细胞数和血液白细胞数,临床症状明显改善,其中高、中剂组效果较好,说明该中药复方灌注液对奶牛急性子宫内膜炎自然病例具有显著治疗效果,推荐临床使用剂量为100mL/次,隔天1次,连用3次。     

环境因素对散养奶牛的繁殖行为和繁殖性能的影响

1991～1994年在洛阳市奶牛场连续观察散养与栓系饲养体制下奶牛的发情表现、发情地点及每日的发情时间分布，统计每月的受胎率和奶牛的产后首次配种时间。结果表明，在散放饲养条件下，奶牛发情明显，发情行为期长；夏、冬季的受胎率低于春、秋季，明显地受温度的影响和五项气象因素的综合作用；五项气象因素对产后首次配种时间的综合影响显著。     

Effect of indoor energy restriction level and management on beef production in Belgian Blue double‐muscled cow‐calf pairs

One hundred and twenty‐six cows were involved to investigate the impact of energy (E) restriction (100%, 90%, 80% and 70% of total energy requirements) during the indoor period and two calf management systems (CMS: suckling or rearing). An E restriction during the indoor period resulted in a loss of body weight, even for E100, which was compensated during the re‐alimentation period, but body weight remained lower in suckling than in non‐suckling cows. The cows yielded 213 full‐term gestations and 8 abortions. Abortion was not affected by E (p = 0.187) or CMS (p = 0.804). Calving interval was neither affected by E (p = 0.775) but tended to be longer in suckled cows (p = 0.087). E reduced body weight and body condition score (BCS) at the end of the calving interval, while CMS only affected BCS. E70 resulted in a higher colostrum yield than E100 and E 90 but immunoglobulin content was not affected (p = 0.759). Cow culling was not affected by E or CMS. It increased from 12.9% to 22.2% and 32.5% for cows with a BCS at parturition lower than 1.5 or between 1.5 and 2.0, or higher than 2 respectively. Calf birth weight was neither affected by E or CMS, but there was an interaction between E and dam age (p = 0.050). Increasing the E restriction tended to reduce calf survival (p = 0.089). Performance of the surviving calves was not affected by E, but suckling calves gained faster than rearing calves (p < 0.001). Beef production by the cow‐calf pair was not different between energy levels (p = 0.738), but it was 10.8% lower for E70 than for E100 cows. It is not appropriate to apply an E restriction of more than 10–20% for maximum cow reproductive traits and calf performance.