Sayed Mortaza Alavi Shoushtari - Department of Theriogenology, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran
Siamak Asri Rezaie - Department of Internal Medicine and Clinical Pathology, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran
Amir Khaki - Department of Theriogenology, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran
Abulfazl Belbasi - Graduate Student, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran
Hamid Tahmasebian - Graduate Student, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran.

To investigate uterine fluid and serum copper (Cu) and zinc (Zn) variations during the estrous cycle in water buffaloes, ۷۱ genital tracts and blood samples were collected from the abattoir in Urmia, Iran. The phase of the estrous cycle was determined by examining ovarian structures; ۱۸, ۱۵, ۱۶ and ۲۲ were pro-estrous, estrous, met-estrous and diestrous, respectively. The uterine fluid was collected by gentle scraping of the uterine mucosa with a curette. Blood serum and uterine fluid samples of ۷۱ pre-pubertal buffalo calves were also collected and treated in similar manners. The mean (± SEM) total serum (۷۷.۱۰ ± ۱.۵۰ µg dL-۱) and uterine fluid (۲۹۶.۴۰ ± ۹.۴۰ μg dL-۱) Cu in cyclic cows was higher than the values of ۵۴.۰۰ ± ۱.۱۰ μg dL-۱ and ۱۳۳.۴۰ ± ۵.۷۰ μg dL-۱ in pre-pubertal calves, respectively. Blood serum (۱۱۴.۶۰ ± ۳.۲۰ μg dL-۱) and the uterine fluid (۳۴۹.۹۰ ± ۸.۹۰ μg dL-۱) Zn content in cyclic cows were also higher than those (۹۸.۸۰ ± ۱.۵۰ μg dL-۱ and ۲۴۶.۶ ± ۴.۵۰ μg dL-۱ respectively) in pre-pubertal calves. Serum Cu in pro-estrus and estrus were lower than those in other stages and also lower than those in the uterine fluid. The lowest serum Zn content was recorded in pro- and met-estrus, while in the uterine fluid it was observed in estrus. In all stages of estrous cycle the uterine fluid Zn content was significantly higher than those of the serum. These results suggested that during the estrous cycle in the buffalo cows, Cu and Zn were actively secreted in uterine lumen and were not dependent on blood serum. The values also increased after puberty.

Buffalo, Estrous cycle, Uterine fluid, copper, Zinc