Influence of age, body weight on some reproductive organs of growing holstein friesian bulls

The influence of age and body weight on some genital organs was studied for 22 Holstein Friesian bulls aged 12-36 months. The bulls under investigation were from three farms and were examined at 2-week intervals. Age, body weight and measurements of some reproductive organs were positively significantly correlated among each other. Meanwhile, organs were significantly positively correlated [P <0.01] to the age from 12 to 36 months, and were significantly increased with the increase of body weight. It could be concluded that the biometry of genital organs was increased linearly as age and body weight increased in Friesian bulls, accordingly the age and body weight of bulls must be taken into consideration before selection and introducing in breeding program

Studies on certain reproductive aspects of Friesian holstein cows under farm conditions in Libya 2 Factors affecting the lifetime performance

The factors affecting the reproductive performance of local Friesian Holstein dairy herd near Tripoli on the north west of Libya were evaluated with respect to age at first calving, herd life, gestation period length, throughout the 5th parities. In addition, the correlation between the gestation period and both the calves's weight and dam's age within the different seasons as well as the average weight of the born calves during the 5th parities was also studied. The first calving age and the herd life averaged 30.31 and 89.28 months respectively. The average gestation period length during the first parity was the shortest [277.43 days] in comparison with the subsequent parities. The averages of the 2nd, 3rd, 4th and 5th parities were 278.80, 279.39, 280.03 and 281.74 days, respectively. Investigation of the relationship between the length of gestation period and the weights of the new borns within season basis showed unclear pattern; Exceptionally, the weight of the male calves of the 4th parity in winter, 1st parity in spring and during the 5th parities of summer and autumn showed positive strong correlations. The female calves weights showed also strong positive correlations during 2nd parity of winter and the 4th parity of summer only. Neither positive nor negative correlation between gestation period length against the dam's age was obtained in this data. Males were consistently heavier than females for all parities

Prognosis of parturition through some measurements on the dam and foetus in SMR cows

This study was applied on 68 SMR cows. The distance between the tuber coxae of the pelvis was measured in 56 cows two and one days before, during and one day after parturition, as well as in 12 nonpregnant cows. The diameter of the fetlock joint of the fetus was measured at the beginning of the expulsive stage of parturition. The sex and weight of the fetus were recorded immediately after delivery. The type of parturition was considered as normal if no outside help was needed. The results revealed that there was a significant increase in the distance between the two tuber coxae of the pelvis 2 days before [in pluriparous cows] and one day before [in primiparous cows] parturition and decrease one day after parturition. All animals having a distance over 38 cm in primiparous and 42 cm in pluriparous cows during parturition gave normal birth. A positive correlation between the diameter of the fetlock joint of the fetus and its weight during parturition was recorded. Therefore, the measurement of the distance between tuber coxae of the dam and the diameter of the fetlock joint of the fetus during parturition may give an idea about the physiological changes of the pelvis and the size and weight of the fetus and consequently may be of help in the prognosis of parturition