Authors : O.O. Demiral , M. Un , M. Abay , T. Bekyurek and N.O. Atabay
Abstract: In present study it was aimed to investigate the effectiveness of ES via prostaglandin F2 (PGF2 ) admistration and Timed Artificial Insemination (TAI) in multipar and nullipar Akkaraman breed sheep. The study used a total of 20 animals which were divided into 2 groups: Group 1 = 10 multipar ewes (2-4 years old) and Group 2 = 10 nullipar ewes (1, 5 years old). All animals were injected with 125 �g Cloprostenol (Estrumate® DIF Istanbul Turkey) at nine day intervals. Ewes were inseminated vaginally 42 h after the second PGF2 administration with the semen which were collected from 6 purebreed Akkaraman rams (2-3 years old) and diluted at 150�106 motile spermatozoa / 0.5 mL dose. Progesterone (P4) levels in blood samples were assessed at the moment of hormone injections and after 3 days. Thirty days after the inseminations, pregnancies were diagnosed via ultrasonography. Pregnancy rates were found to be 40 % for multipar and 20 % for nullipar ewes (p>0.05). P4 levels in multipar and nullipar animals at the first PGF2 administration, three days after the first PGF2 administration, at the second PGF2 administration and three days after the second PGF2 administration were measured as (median) 2.67-3.67 (p>0,05), 0.96-0.86 (p>0,05), 6.26-5.24 (p<0,05) and 0.99-1.25 ng mL 1 (p<0.05), respectively. It was concluded that multipar animals yielded better responses to ES accomplished through PGF2 administration. The Nullipar animals should be considered as a negative factor for the sucsess of TAI via synchronization of estrus with PGF2 in ewes.
O.O. Demiral , M. Un , M. Abay , T. Bekyurek and N.O. Atabay , 2008. The Effectiveness of Synchronization of Estrus via Prostaglandin F2 Administration and Timed Artificial Inseminaton in Multipar and Nullipar Akkaraman Breed Ewes. Research Journal of Animal Sciences, 2: 41-44.