Subscribe Now Subscribe Today
Science Alert
 
Blue
   
Curve Top
Pakistan Journal of Biological Sciences
  Year: 2007 | Volume: 10 | Issue: 16 | Page No.: 2709-2713
DOI: 10.3923/pjbs.2007.2709.2713
 
Facebook Twitter Digg Reddit Linkedin StumbleUpon E-mail

Influence of hCG Administration after AI on Conception Rates and Serum Progesterone Concentration in Cattle

N. Shams-Esfandabadi , A. Shirazi , P. Mirshokrai and M. Bonyadian

Abstract:
The objectives of this study were to determine the effect of administration of exogenous hCG 5 days after Artificial Insemination (AI) on serum progesterone concentration and conception rate in lactating dairy cows. In this experiment 5 days after AI the cows were alternately assigned randomly to treatment group (n = 70) received an injection of 3000 IU hCG (Chorulon, each vial contained 1500 IU, Intervet, Holland) and control group (n = 88), received no treatment. On day 5 and 12 blood samples from 20 of cows (10 in each group) were obtained to measure serum progesterone concentrations. The study population was stratified by parity, milk yield production, number of AI and Days in milk. Cows that were detected in estrous after days 18-24 were reinseminated and recorded as no pregnant (open) to the prior AI. The uteri of cows not observed in estrous were palpated per rectum 45-50 days after insemination to determine pregnancy status. Pregnancy proportion in treatment and control groups were 27.5 and 35.2%, respectively. The results demonstrated that there was no significant differences between two groups (p<0.05). Mean serum progesterone concentrations did not differ between treatment and control groups on day 5 (2.94±0.65 versus 2.98±0.36 ng mL-1). On day 12 serum progesterone concentrations were greater (p<0.05) in the treatment group compared with control group (16.07±3.64 versus 8.71±0.86 ng mL-1). Regardless of treatment, parity, milk yield production, number of AI and days in milk had no effect on the pregnancy rate. In conclusion, 3000 IU of hCG 5 days after insemination did not improve pregnancy rate in dairy cows, despite the fact that serum progesterone concentration were higher in treatment group.
PDF Fulltext XML References Citation Report Citation
How to cite this article:

N. Shams-Esfandabadi , A. Shirazi , P. Mirshokrai and M. Bonyadian , 2007. Influence of hCG Administration after AI on Conception Rates and Serum Progesterone Concentration in Cattle . Pakistan Journal of Biological Sciences, 10: 2709-2713.

DOI: 10.3923/pjbs.2007.2709.2713

URL: https://scialert.net/abstract/?doi=pjbs.2007.2709.2713

COMMENT ON THIS PAPER
 
 
 

 

 
 
 
 
 
 
 
 
 

 
 
 
 
 
 
 
 
 
 
 
 

Curve Bottom