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871.
872.
黄牛及其改良牛的配种受胎率是体现肉牛生产力的重要指标。为提高母牛的繁殖率和肉牛业的经济效益,本文对多年来通过外部观察和直肠触诊积累的母牛发情时的行为表现及生理特点进行了初步的汇总分析,结果表明:①爬跨行为是群养牛群发情的主要特征,而鸣叫不安、食欲减退是散养牛发情的主要特征;②母牛发情多在早晨6:00-11:00及下午16:00- 19:00,发情持续期平均为25-26 h;③由发情开始到排卵的持续时间平均为33.98 h;排卵高峰多集中在12:00-14:00和晚上23:00到次日凌晨3:00;④卵泡发育以直径0.8-1.2 cm居多;⑤在发情开始后24 h输精,可望有一个较高的受胎率。 相似文献
873.
874.
875.
奶牛日粮中添加油菜籽、菜油及脂肪酸钙对奶牛产奶量及奶品质的影响 总被引:2,自引:0,他引:2
试验选用泌乳3~5个月,2~5胎次,体重相近,健康无病,产奶量相近(P>0.05)的奶牛36头,随机分为4组,其中:对照组喂给基础日粮,试验1、2和3组分别在基础日粮中添加油菜籽(350 g/d·头)、菜油(150 g/d·头)和脂肪酸钙(200 g/d·头)。通过30 d对比饲养试验。结果表明:试验1、2、3组的奶牛日均产奶量分别比对照组相对提高0.88(P<0.05)、0.31(P>0.05)、0.70 kg/d·头(P<0.05)。各组间奶牛干物质采食量及饲料干物质利用率均无显著差异(P>0.05);试验1、2、3组牛奶中乳蛋白和非脂乳固体有增加的趋势,但不明显(P>0.05);试验1、2、3组与对照组的乳脂率无明显变化(P>0.05)。与对照组相比试验1组每头奶牛每天可增加纯收入1.08元,试验2组亏损0.06元,试验3组亏损0.14元;从而认为在日粮中添加油菜籽、菜油、脂肪酸钙可以提高奶牛产奶量,其中以添加油菜籽的经济效益最好。 相似文献
876.
Electro-acupuncture and Chinese herbs for treatment of cervical intervertebral disk disease in a dog
Ayne Murata Hayashi Júlia Maria Matera Tatiana Soares da Silva Ana Carolina Brand?o de Campos Fonseca Pinto Sílvia Renata Gaido Cortopassi 《Journal of veterinary science (Suw?n-si, Korea)》2007,8(1):95-98
A non-ambulatory dog with tetraparesis following a pain episode that had evolved over 2 months was submitted for medical treatment and diagnosed with intervertebral disk disease at C3-C4 and dorsal extradural compression at C1-C2 and C3-C4 using myelography and computed tomography. The dog experienced ambulation recovery after 15 days of treatment with only electroacupuncture and Chinese herbal medicine, with marked improvement occurring after only 10 treatments. Six months of follow-up demonstrated that the dog was stable and had no recurrence of symptoms. Therefore, it was concluded that the combination of electroacupuncture and Chinese herbal medicine was responsible for motor rehabilitation. 相似文献
877.
ZHAO Shoupei LI Xuemei GAO Yuhong SUN Xinsheng GUO Jianjun HAO Zangen MAO Sen 《中国畜牧兽医》2007,47(11):3510-3517
The purpose of this study was to evaluate thermal environment of cowshed in four seasons in central plain of Hebei,and analyze the correlation between the temperature parameters and physiological indexes of dairy cows.Three dairy cow houses with different building structures were selected,the thermal parameters (ambient temperature (Ta) and relative humidity (RH)) and physiological parameters (respiratory rate,rectal temperature and body surface temperature) were detected.The results showed that the Ta,RH and index of temperature and humidity (THI) changed significantly in four seasons (P<0.05),the average daily temperature in summer was the highest (28.59 ℃),and the average daily temperature in winter was the lowest (1.55 ℃).In summer,dairy cows were suffering from mild heat stress for 15.5 h every day,and from moderate heat stress for 6.0 h.In winter,dairy cows were under mild cold stress for an average of 12.0 h per day.The Ta and THI of three cowsheds in each season had no significant differece (P>0.05),except for that in winter.Compared with the cowshed with low wall or roller blind,the average Ta in the cowshed with only roof was 0.80-1.27 ℃ higher in summer and 1.36-1.84 ℃ lower in winter.In addition,the physiological parameters of dairy cows were extremely significantly higher in summer than those in other seasons (P<0.01).The respiration frequency or rectal temperature of cows among cowsheds in summer were significantly different (P<0.05),and the seasonal difference in body surface temperature was significant (P<0.05).Correlation analysis of thermal parameters and cow physiological parameters showed that the respiratory frequency,rectal temperature and body surface temperature were positively correlated with THI and Ta (P<0.05).However,there was no significant correlation between physiological parameters and RH (P>0.05).The results provided scientific basis for environment evaluation of cows,and physiological status of dairy cows were inferred according to environmental thermal parameters,which provided data for occurrence and early warning of stress. 相似文献
878.
介绍奶牛体细胞计数的概念、特征、测量方法、体细胞值所受到的影响及其在乳制品行业的应用,尤其是在降低奶牛乳房炎发病方面,用体细胞值作为一种遗传性状进行选择以提高奶牛对乳房炎抗性的应用。 相似文献
879.
880.