黑白花奶牛几项血清生化指标的测定

对郑州工作奶站33头健康黑白花奶牛几项血清生化指标进行了测定。这些测定值可作为郑州地区奶牛营养监测和营养状态判断的参考数据。     

外源性cAMP和cGMP对黑白花奶牛泌乳性能的影响

对泌乳黑白花奶牛分别注射cAMP+cGMP组合剂、组合剂cGMP和自制环核苷酸组合剂(cAMP+cGMP).注射当月各组奶牛产奶量无差异;注射后1月,奶牛日平均产奶量比对照分别提高14.1%、23.6%和19.7%,差异达显着水平(P<0.05).对血液和乳生化指标测定结果表明,cGMP是提高黑白花奶牛产奶量的主要调节物;环核苷酸主要通过cGMP升高血糖、加快乳腺细胞乳的合成速度,从而使产奶量提高.     

娟姗牛与荷斯坦牛X-性控冷冻精液试验研究效果分析

采用娟姗牛与荷斯坦牛X-性控冷冻精液,给娟姗母牛、荷斯坦母牛及胚胎移植供体进行人工授精,以探索两种冷冻精液人工授精受胎效果及供体牛生产胚胎效果。研究结果表明,人工输精试验牛情期受胎率及供体母牛的平均可用胚胎数和可用胚胎率受公牛X-性控冷冻精液的影响;人工输精试验牛的受胎率青年牛优于经产牛,而荷斯坦牛的优于娟珊牛;生产胚胎的供体牛,综合可用胚胎数和可用胚胎率,在同一品种上青年牛的效果优于经产牛,在不同品种而同一年龄上的荷斯坦牛优于娟珊牛。     

Effects of calving age, breed fraction and month of calving on calving interval and survival across parities in Irish spring-calving dairy cows

The objective of this study was to investigate the effect of parity, age at calving, percentage North American Holstein-Friesian and calving date on subsequent calving interval and survival to facilitate the estimation of transition probabilities for month of calving. The economic value of traits that influence calving date, age distribution and survival can be assessed in models using a transition probability matrix. Such a matrix contains the probabilities that a cow of a particular age or breed calving in a particular month will calve in the same, an earlier or later month next year, or be culled. Following editing 1,046,855 calving records in spring-calving herds between the years 1990 and 2004 were analysed. Shorter calving intervals were associated with cows calving later in the calendar year. Age at first calving of < 24 months resulted in longer calving intervals to second calving across all levels of Holstein percentage with cows calving for the first time at 25–26 months of age having the shortest subsequent calving interval. Age at second calving of 37–38 months and third calving of 49–50 months were optimum for shorter subsequent calving intervals. Calving interval increased with Holstein percentage across the first 5 parities. Survival rate decreased with later month of calving and with older parities. When survival rate was measured as the ability of the cow to re-calve within 500 days, the highest survival rate was found in cows calving at 25–26 months of age whereas there was a noticeable reduction in survival across all parities in the 88–100% Holstein percent category.     

奶牛各胎次产乳量相关性研究与终生产乳量的早期预测

本文通过对荷斯坦奶牛１～７胎各胎次产乳量相关性的研究,分析了各胎次之间产乳量的相互关系,泌乳的规律性,并通过早期产乳量 生产乳量,筛选最佳预测终生产乳量的回归方程,预测的终生产乳量的相关系数达到０．７８１９。     

西宁地区黑白花奶牛,猪及藏犬红细胞免疫功能初探

应用红细胞Ｃ＿３ｂ受体（ＲＢＣ－Ｃ＿３ｂＲ）花环和红细胞免疫复合物（ＲＢＣ－ＩＣ）花环试验对西宁地区饲养的３５例黑白花奶牛，２０例８０日龄左右的荣昌猪及６例藏犬的红细胞免疫功能，分别进行了检测。结果证明被测三种动物的红细胞膜上均具有Ｃ＿３ｂＲ，并测得ＲＢＣ－Ｃ＿３ｂＲ及ＲＢＣ－ＩＣ的花环百分率分别为：牛９．３４±６．１４％及６．４９±３．１４％，猪４．３５±１．０８％及２．３５±１．１％，藏犬３．５９±０．４８％及１．３４±０．３３％。从而证明红细胞免疫系统（ＲＣＩＳ）亦适用于黑白花奶牛、荣昌猪及藏犬等动物。文中还对黑白花奶牛血清中红细胞免疫粘附（ＲＣＩＡ）促进因子和抑制因子进行了探讨。     

黑白花奶牛泌乳曲线参数的方差组份和遗传特性分析

本文根据北京黑白花奶牛８６０个有完整记录的泌乳期资料，利用Ｗｏｏｄ模型进行了泌乳曲线参数估计，并通过最小二乘法对估计结果进行了方差分析和相关性分析，估计了曲线参数的遗传力（ｈ＾２）、遗传相关（ｒＡ）、表型相关（ｒＰ）和环境相关（ｒＥ）。方差分析表明，父畜和胎次对产奶量（ＭＹ）、估计产奶量（ＥＭＹ）、ａ、ｃ、高峰月份（ＭＰＹ）和高峰月产奶量（ＰＹ）有极显著影响（Ｐ＜０．０１）；对持久力有显著影响（Ｐ     

Postpartum follicular and luteal activity in Holstein-Friesian cows genetically selected for high or low mature bodyweight: Relationships with follicle stimulating hormone,insulin, insulin-like growth factor-1 and growth hormone

AIM: To investigate ovarian follicular and luteal activity during the postpartum period of cows genetically selected for high or low mature bodyweight, in relation to metabolic and reproductive endocrine parameters, to determine whether there are differences between strains that could affect fertility outcomes.

METHODS: The presence of follicles ≥5 mm diameter and luteal structures was mapped in the ovaries of 12 high (heavystrain) and 12 low (light-strain) mature bodyweight cows by daily trans-rectal ultrasonography from Day 7 postpartum until the end of their first normal oestrous cycle. Blood samples were collected daily, for measurement of concentrations of follicle stimulating hormone (FSH), progesterone, growth hormone (GH), insulin-like growth factor-1 (IGF-1), and insulin. Intervals to first ovulation were calculated from ultrasonography data.

RESULTS: Heavy-strain cows had shorter intervals than light-strain cows from calving to the emergence of the first (9.0 (SE 0.9) vs 12.4 (SE 1.3) days) and second (16.4 (SE 1.8) vs 20.6 (SE 1.6) days) dominant follicles (p<0.05). Concentrations of FSH in heavy-strain cows prior to the emergence of the second, third and fourth dominant follicles were higher than in light-strain cows (p<0.05). Heavy-strain cows were more likely to have a large (>15 mm diameter) follicle earlier than light-strain cows (p<0.01). Concentrations of insulin and IGF-1, but not those of GH, were higher in heavy- than light-strain cows during the postpartum period (p=0.01 and p=0.02, respectively), and concentrations of both on Day 6 were inversely related to the time of emergence of the first dominant follicle (p>0.01).

Concentrations of progesterone were similar in both strains of cow until Day 10 of the first oestrous cycle, but thereafter were higher in light- than heavy-strain cows until Day 16. Progesterone concentrations in heavy-strain cows declined earlier and more rapidly than in their lighter counterparts.

CONCLUSION: These results indicate that there is a rapid postpartum resumption of follicular activity in both heavy-and light-strain cows, but that there is an earlier emergence of dominant follicles and ovulation in the former. Differences in luteal function, in terms of lower dioestrus progesterone concentrations and an earlier onset of luteolysis, in heavy- than light-strain cows might be sufficient to impair the fertility of the former.     

Some Arthropods Affecting Man and Livestock in New Zealand

Extract

At present, the standard tuberculin test used in New Zealand is the subcaudal intradermal test using 0·1 ml Commonwealth Serum Laboratories Synthetic Medium tuberculin, animals being classified as positive or negative to the test on the presence or absence of any swelling either visible or palpable at the site of the injection at the 96th hour.     

年龄、胎次、配种月份对奶牛产犊性别的影响

根据西宁某奶牛场1984-1995年荷斯坦奶牛的配种产犊记录,按不同配种年龄、胎次与配种月份所产犊的性别进行统计分析。结果表明:配种年龄对奶牛产犊性别无显著影响(p>0.05);胎次与奶牛产犊性别的关系表现为第三胎所产公犊显著多于母犊(p<0.05),其它各胎次差异均不显著(p>0.05);配种月份对奶牛产犊性别的影响表现为3-5月配种所产犊牛有母犊多于公犊趋势,但差异不显著(p>0.05),6月-9月配种所产犊牛公犊显著多于母犊(p<0.05),其余各月份差异均不显著(p>0.05)。