Comparison of three types of GNRH administration in heat synch program on pregnancy rate and LH surge in dairy cows

Subject Areas : clinical veterinary science

T.  Taktaz Hafshejani, ¹ (Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran)
S.  Khadivi Boroujeni, ² (Faculty of Veterinary Medicine, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran)
فرشاد  Babakhanian Boroujeni, ³ (Faculty of Veterinary Medicine, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran)

Received: 2016-11-04 Accepted : 2016-11-04 Published : 2013-12-22

Keywords: Cow, conception rate, GnRH, LH hormone,

Abstract :

The increasing human population and the reduction of animal food sources in the other side led researchersinto effective strategies for increasing livestock production. In this case if we can increase pregnancy rates incow herds will reach our goals faster. Purpose of this study was to determine the effects of three different typesof Gonadotrophin releasing hormone (GnRH) on the pregnancy rate and surge of LH hormone levels in heatsynchronization program. This study done on 130 cows in three separate groups. This was conducted in primarygroup with injection of 15μg (3cc) Buserelin Acetate by commercial brand of Vetocept® on zero day ,second groupwith injection of 100μg (1cc) Gonadorelin Acetate by commercial brand of Gonabreed® on zero day and thirdgroup by injecting 12/6 μg (3cc) Alarline Acetate (Luliberin A) by commercial brand of Vetarolin® on zero dayand continued for all three groups on next 7 days injection of 500μg, PGF2α by commercial brand of estroPLAN®and next 24 hours injection of 1mg Estradiol Benzoate with commercial brand of Vetastrol®. Pregnancy rates forthe frst group 34/14%,second group 40% and the third group 38/63%, respectively. and LH hormone Surge rateafter 1 hours later for the frst group 2/44, second group 1/59, third group 2/30,respectively. It is concluded thatpregnancy rates were higher in Gonabreed® Group than two other groups, but no statistically signifcant differencewas seen among them.(p>/05) in Vetocept® group surge of LH hormone was more than two other groups butthere was no signifcant difference among them. (P>/ 05) as well as there was no signifcant statistical differencebetween pregnancy rates of cows with normal postpartum uterine Examination in three groups. (p>/05) In additionto it, there was no signifcant statistical difference between pregnancy rate of cows with abnormal post partumuterine Examination but pregnancy rates in this group of cows was lower.(p>/05).