%0 Journal Article
%T Comportamiento reproductivo de vacas criollas con amamantamiento restringido y sincronizaci¨®n del estro
%A Z¨¢rate-Mart¨ªnez
%A Juan Prisciliano
%A Ram¨ªrez-God¨ªnez
%A Jos¨¦ Alejandro
%A Rodr¨ªguez-Almeida
%A Felipe Alonso
%J Agronom¨ªa Mesoamericana
%D 2010
%I Scientific Electronic Library Online
%X reproductive performance of creole cows with restricted suckling and estrus synchronization. the objectives were to study the reproductive performance, initiation of post-partum ovarian activity, response to restricted suckling, estrus synchronization, and conception rate using artificial insemination at a fixed time of creole rodeo cows (c). in chihuahua, m¨¦xico, during the summer 2008, twenty-seven cows were used over 95 d, and the beginning of post-partum ovarian activity was detected by ultrasonography. hormone treatment for estrus synchronization was administered to 22 cows (n=11 per group). in treatment1 (t1) the cows (n=11) received a cidr with 1,9 g of progesterone and one im injection with 1 mg of ¦Â-estradiol + 50 mg of p4. the cidr was removed after d 7 and an im injection of 30 mg of pgf2¦Á was applie d. after 24 h, 1 mg of ¦Â-estradiol was applied, and the cows were inseminated 54 h after removing the cidr. t2 (n=11) was similar, but the im injection contained ¦Â-estradiol only. the c showed aggressive behavior (ab) during the restricted suckling. the average days from the beginning of the ovarian activity were 11,66 d and only 11,11% of the cows exhibited estrus during initial ovarian activity. one hundred percent of the animals underwent estrus on d 9 post synchronization, there were not differences (p>0,05) among the levels of progesterone of the t1 (4,94¡À0,331 ng/ml) vs the t2 (4,87¡À0,30 ng/ml. there was a t*ds interaction for concentrations of progesterone and e2 (p=0.06). there were no differences (p>0.05) in conception rate (18,8%). adding p4 with a cidr did not increase the levels of progesterone in c.
%K bovine
%K progesterone
%K estradiol
%K corpora lutea.
%U http://www.scielo.sa.cr/scielo.php?script=sci_abstract&pid=S1659-13212010000100013&lng=en&nrm=iso&tlng=en