Pit-1基因在荷斯坦奶牛中的多态性及其与估计育种值的相关性研究

本试验应用PCR—RFIIP技术研究了宁波荷斯坦奶牛PIT-1基因的基因和基因型频率;并比较了基因型频率与产奶量估计育种值和乳脂率估计育种值的相关性。结果显示,等位基因A和B的频率分别为28％和72％,基因型AA,AB和BB的频率分别为5．4％,45．9％和48．7％。各基因型间估计育种值均没有表现出显著差异。     

Development of a stereotaxic instrument for study of the bovine central nervous system

We have developed a bovine stereotaxic instrument in this study to be used for Holstein cattle from weanling to adult age. The bovine stereotaxic instrument is derived from the Horsley-Clarke principle. A pair of straight ear-bars and orbital ridge pieces with their carriers, head clamps, AP bars are symmetrically arranged across the head pace. For holding the heavy heads, a hard palate and a mandibular support are designed to be placed on the surface of the base frame. A new manipulator with long working distance has also been made. For ventriculography, a holder inserting an X-ray film cassette is placed just next to the AP bar. Finally, the instrument was combined together with an oil-operated lift, so that it can be adjusted to a proper height. Details of this instrument are described in this paper.     

Changes in blood β-hydroxybutyrate and glucose concentrations during dry and lactation periods in Iranian Holstein cows

Clinical and subclinical ketoses are important metabolic diseases in dairy cattle during early lactation and are associated with losses in milk production and several other periparturient diseases. Limited information is available regarding the prevalence of clinical and subclinical ketoses in dairy herds in Iran. The objectives of this study were (1) to detect serum β-hydroxybutyrate (BHB) and glucose concentrations during pre- and postparturition periods, (2) to investigate the correlation between the blood concentrations of BHB and glucose pre- and postpartum, and (3) to establish a cutoff point of blood BHB concentration for detection of subclinical ketosis (SCK) in Iranian Holstein cow. In the present study, blood BHB and glucose concentrations of 13 Iranian Holstein cows (4–6 years old) from three commercial dairy herds were measured at 60, 30, and 7 days before and 30 and 60 days after calving. Cows had the highest concentration of BHB and the lowest concentration of glucose at 30 days postpartum period, which were significantly (p < 0.05) different from the prepartum period. High negative correlation coefficients (p < 0.05) were observed between serum BHB and glucose concentrations at 7 days prepartum (r = −0.84) and 30 days postpartum (r = −0.76) periods. The distribution of blood BHB concentrations seemed to suggest a cutoff point of 1,200 μmol/l to distinguish healthy cows from cows with SCK. At this cutoff point, 15.4% of cows had serum BHB concentration higher than the cutoff point of 1,200 μmol/l. The results of this study showed that the concentration of blood BHB during lactation is significantly higher than in the dry period, possibly due to higher energy demands of animals at this time, and the peak prevalence of SCK occurs in the first month after calving.     

犊牛代乳应用试验效果观察

选择日龄为20d的小犊牛45头,随机分为对照组、试验组A、试验组B,试验组A为15头,试验组B为16头,对照组为14头。采用犊牛代乳粉和犊牛代乳料,与鲜奶做对比试验,连续饲喂70d,结果试验组B日均增重1.057±0.144kg/头,比对照组0.961±0.345kg/头增加0.096kg,提高9.99%,差异显著(P<0.05),试验组A日均增重0.980±0.3849kg/头比对照组0.961±0.345kg/头增加0.019kg,提高1.98%,差异不显著(P>0.05)     

影响本地杂交黄牛胚胎移植妊娠率的因素分析

本试验选用本地杂交黄牛作为受体,在同一饲养条件下,利用自然发情的方法,移植黑白花奶牛提供的胚胎,移植结果显示:胚胎发育日龄和受体发情日期同步移植,受胎率44.2%,8天受体移植7天桑葚胚,受胎率38.9%,7天受体移植8天囊胚,受胎率35.5%,三者比较差异不显著(P>0.05)。冻胚分别移植A、B、C级黄体的受体,其受胎率分别为40.4%、37.2%、33.3%,三者差异不显著(P>0.05);而鲜胚移植A、B、C级黄体,受胎率分别为48.6%,40.3%,25.8%,A、B级黄体移植受胎率差异不显著(P>0.05),A、C级黄体差异极显著(P<0.01),B、C级黄体差异显著(P<0.05)。不同胚胎质量比较:一、二、三级胚胎移植受胎率分别为50.5%、42.6、25.2%,三者比较,一级、二级胚胎受胎率差异不显著(P>0.05),但二级和三级差异显著(P<0.05),一级和三级差异极显著(P<0.01)。移植单胚和双胚的受胎率分别为25.2%,40.2%,二者差异显著(P<0.05)。     

添加Globatan对中国荷斯坦奶牛奶产量和乳成分的影响

试验组日粮中添加Rode＆Rode提供的Globatan（主要成分为欧洲甜栗树的提取物）。通过试验分别测定在新疆实际饲养和管理条件下，添加Globatan对中国荷斯坦奶牛奶产量和乳成分的影响。     

日粮中添加烟酸对泌乳早期奶牛产奶性能的影响

本试验选用 12头处于泌乳早期的中国荷斯坦奶牛 ,随机分为对照组、试验 1组、试验 2组 ,每组 4头 ,研究烟酸对中国荷斯坦奶牛泌乳早期的产奶量、乳脂率的影响。对照组饲喂基础日粮 ,试验 1组、试验 2组每头每日在基础日粮中分别添加 3g和 6g烟酸 ,经 30d饲养试验 ,结果表明 :试验 1组和试验 2组比对照组头日均多产标准乳 1.0 6kg(P <0 .0 5 )、1.85kg(P <0 .0 1) ,比对照组分别提高 3.2 1%、5 .6 1% ,对照组和试验组间的乳脂率差异不显著 (P >0 .0 5 )。     

From the Cover: PNAS Plus: Changes in genetic selection differentials and generation intervals in US Holstein dairy cattle as a result of genomic selection

Seven years after the introduction of genomic selection in the United States, it is now possible to evaluate the impact of this technology on the population. Selection differential(s) (SD) and generation interval(s) (GI) were characterized in a four-path selection model that included sire(s) of bulls (SB), sire(s) of cows (SC), dam(s) of bulls (DB), and dam(s) of cows (DC). Changes in SD over time were estimated for milk, fat, and protein yield; somatic cell score (SCS); productive life (PL); and daughter pregnancy rate (DPR) for the Holstein breed. In the period following implementation of genomic selection, dramatic reductions were seen in GI, especially the SB and SC paths. The SB GI reduced from ∼7 y to less than 2.5 y, and the DB GI fell from about 4 y to nearly 2.5 y. SD were relatively stable for yield traits, although modest gains were noted in recent years. The most dramatic response to genomic selection was observed for the lowly heritable traits DPR, PL, and SCS. Genetic trends changed from close to zero to large and favorable, resulting in rapid genetic improvement in fertility, lifespan, and health in a breed where these traits eroded over time. These results clearly demonstrate the positive impact of genomic selection in US dairy cattle, even though this technology has only been in use for a short time. Based on the four-path selection model, rates of genetic gain per year increased from ∼50–100% for yield traits and from threefold to fourfold for lowly heritable traits.Genetic improvement of livestock during the second half of the 20th century using pedigree and performance data has been very successful, particularly in dairy cattle populations (e.g., ref. 1). The improvement of dairy cattle has depended heavily on the use of artificial insemination (AI) to maximize the impact of elite bulls globally. Historically, progeny testing (2), or the characterization of these AI bulls by measuring and comparing performance of daughters, has been a critical step in identifying the very best bulls for widespread use. However, traditional genetic improvement schemes in dairy cattle have been limited by time required and expense of the progeny test paradigm. This process remained relatively slow because of the substantial time needed to accumulate sufficient daughter phenotypes to compute genetic evaluations with high accuracy. The recent development of genomic selection (3) programs based on single-nucleotide polymorphism genotypes was expected to increase rates of genetic gain (3, 4) in several ways, including shortened generation interval(s) (GI) (5, 6) and increased reliability of predicted breeding value(s) (PBV) (7). A doubling of rates of genetic gain was predicted when comparing genomic evaluations and traditional progeny testing schemes (5, 6, 8, 9). These advantages have been demonstrated in simulations (10, 11), and increased accuracies have been documented in the US Holstein population (12), but response to the incorporation of genomic data into dairy cattle evaluations has not been characterized.In April 2008, the United States released its first unofficial genomic PBV, and official evaluations for Holsteins and Jerseys were published in January 2009 (9). Genomic selection was rapidly adopted by the industry, and more than half of all AI matings in the United States are now made to genomically tested young bulls (13). Genomic breeding values have been available for 6 y, so a characterization was conducted of the dynamic changes in rates of genetic gain associated with alterations in GI and selection differential(s) (SD). Rendel and Robertson (14) described a four-path model of genetic improvement in which genetic progress occurs with differing selection dynamics, partitioned into improvement due to genetic changes in sire(s) of bulls (SB), sire(s) of cows (SC), dam(s) of bulls (DB), and dam(s) of cows (DC). The objective of this study was to measure the impact of genomic selection on SD and GI in US Holstein cattle using this four-path model, and to compare these observed results with those results predicted by theory.     

前外侧入路双钢板固定治疗Holstein Lewis骨折

目的:探讨前外侧入路双钢板内固定治疗Holstein-Lewis骨折的疗效。方法:2003年1月至2015年3月,复旦大学附属上海市第五人民医院收治45例Holstein-Lewis骨折患者。男32例,女13例,年龄21~52岁,平均36.8岁,均合并桡神经损伤。经臂部前外侧入路探查桡神经后,复位骨折端,植入3.5mm加压钢板,置于肱骨干前及外侧联合固定。桡神经根据损伤程度予以修补或松解。记录术后并发症,骨折愈合时间,桡神经功能恢复时间,肩、肘关节屈伸范围。采用UCLA肩关节和Mayo肘关节评分标准评价疗效。结果:本组患者切口均Ⅰ期愈合。随访8~36个月,平均15.3个月。骨折愈合时间3~6个月,平均3.9个月。41例桡神经嵌压水肿及不完全断裂患者于术后3~6个月恢复,平均4.8个月;4例桡神经完全断裂患者于2年后伸腕、伸指功能完全恢复。本组患者术后肩关节外展155°~165°,平均160°。肘关节活动范围125°~135°,平均128.5°。根据加州大学肩关节评分(UCLA)标准,肩关节功能优45例。根据Mayo评分标准,肘关节功能优42例,良3例。结论:前外侧入路双钢板固定治疗Holstein-Lewis骨折,具有内固定可靠,肌群损伤小,桡神经探查修补便利的特点,是一种安全可靠的治疗方式。     

Composition of goat and cow milk produced under similar conditions and analyzed by identical methodology

The aim of this study was to identify, under the best possible conditions, the interspecific differences between the proteins, fat and minerals in goat and cow milk. The protein fractions presented evident differences, especially concerning the amount of α_S1-casein, which was lower in the goat milk (62.8%; P < 0.05). The amino acid profile of the two proteins revealed certain differences, although the total quantity of essential amino acids did not vary (P > 0.05). The composition of fats was well-differentiated, mainly as concerns the content of medium-chain fatty acids (C6–14), which were higher in the goat milk (28.8%; P < 0.05). The same was true for n-6 polyunsaturated fatty acids (10.0%; P < 0.05) and n-3 polyunsaturated fatty acids (51.0%; P < 0.05), and also the total level of conjugated linoleic acid (33.8%; P < 0.05). The quantities of Ca, P, Mg and Cu were greater in the ash derived from goat milk (17.4, 15.6, 16.3 and 66.6%, respectively; P < 0.05). Due to the greater quantity of total solids present in goat milk (16.3%; P < 0.05), all of the above-mentioned differences would be considerably increased by the fact that they refer to the amounts present in a given volume. The differences detected between cow and goat milk mean that the latter constitutes a food of particular interest, in terms of both health and nutrition.