Seasonal Effects on Estrus Behaviours in Dairy Cattles
نویسندگان
چکیده
The present investigation was carried out to evaluate the effects of environmental factors on reproductive performance of bovine (Bos taurus) during summer, winter and spring for one year. The study was performed on free moving animals under natural condition during the two consecutive estrus periods by visual observation. The duration of estrus, numbers of mounts were observed. There was a seasonal effect on the duration of estrus; estrus was longer (P<0.001) in summer as compared to those of winter and spring. In addition, cows were mounted more times in estrus during winter than in summer and spring. The results of this study revealed that season influences on estrus behaviour of cows.
منابع مشابه
The Relationships Between Milk Production and Some Blood Metabolites and Their Effects on Returning to Estrus in Lactating Holstein Dairy Cows
In this study, the relationships and correlations between milk production and some blood metabolites related to energy and protein balance and their effects were investigated on returning to estrus after AI in lactating Holstein dairy cows. Blood and milk samples were collected from sixty lactating Holstein dairy cows based on their reproductive status in 13-17 d post AI. BUN, MUN, glucose, tri...
متن کاملEffects of two different protocols: injection of progesterone vs. injection of GnRH+PGF2a on the onset of estrus in dairy cows with postpartum anestrous
Postpartum anestrous is one of the most important problems in the dairy industry in the world and especially in Iran. The objective of present study was to compare the efficacy of two hormonal programs for recycling of postpartum anestrous cows. For this reason, 230 Holstein cows from 4 similar dairy herds (with totally 2560 cow and unique management and feeding system) located on the suburb of...
متن کاملEffects of two different protocols: injection of progesterone vs. injection of GnRH+PGF2a on the onset of estrus in dairy cows with postpartum anestrous
Postpartum anestrous is one of the most important problems in the dairy industry in the world and especially in Iran. The objective of present study was to compare the efficacy of two hormonal programs for recycling of postpartum anestrous cows. For this reason, 230 Holstein cows from 4 similar dairy herds (with totally 2560 cow and unique management and feeding system) located on the suburb of...
متن کاملComoarison of PCR and bacterial culture methods for diagnosis of dairy cattles subclinical submastitis caused by staphylocuccus aureus
متن کامل
The effect of administration of gonadotropin releasing hormone analogue at estrus or during luteal phase on reproductive performance of dairy cows maintained under sub-temperate climate
Overall, 531 dairy cows were inseminated with the aim to study their reproductive performance following administration of GnRH analogue on different days of estrous cycle with different doses. These cows were divided into six treatment and one control group. Depending upon different treatment groups, Buserelin acetate was injected at a dose of 10.5 µg or 21.0 µg on different days (0, 5 or 12) o...
متن کامل