POST AI CONCEPTION RATE IN CATTLE AT CHAR AREA IN NAGESHWARI UPAZILA UNDER KURIGRAM DISTRICT

Abstract

The present study was conducted to determine the conception rate of cows/heifers artificially inseminated at different villages of Nageshwari Upazila, Kurigram. The study was carried out during the period from August 2013 to July 2015. One hundred and eighty four animals were inseminated using frozen semen. The cows were inseminated between 6-20hrs of onset of heat obtained from data (history) from the owner. A total of 184 cows/heifers of different breed, age, season, body weight and parity were selected and artificial insemination was performed by using frozen semen. The age and interval from caving to AI were recorded by interviewing the farmers and BCS, body weight of cows/heifers measured by eye estimation. Date of AI, bull on/name/breed and authority of used semen were recorded from the AI card given to the farmers by AI technicians. All cows/heifers were examined for pregnancy by rectal palpation of genital tract at 80-90 days post AI. One hundred and seven were inseminated 1 or 2 times and 77 animals for 3 and more services. Out of 184 animals 101 animals were conceived and 83 animals did not conceived. The overall conception rates were 54.9%. A significantly decreased conception rate (p<0.01) was observed in age group more than 8 years than other groups. Upon increasing age the service required for conception was irregular. The conception rate with respect to different parities ranged from 25% to 73%. Cows received insemination at parity 1 showed highest conception rate (73%) and cows received insemination at parity 6 showed lowest conception rate (25%). There was significant difference between them on conception rate (p<0.01). The overall and within group conception rate percentage in Local (52.9%) and Friesian cross (62.3%) cows/heifers were relatively higher than that of Sahiwal cross (40%). However the difference was not significant (p>0.05). The conception rate was observed significantly higher (78.9%) in the cows which were inseminated in spring than the cows were inseminated in summer (29.8%), winter (72.1%) and rainy (35.7%) season. The conception rate was significantly higher (p<0.01) in 1st and 2nd service compared with 3rd services (89.7% vs 6.5%). A proportion of cows, which failed to conceive in the first service repeated in second, third services and or more. More service is required for heifer than older animals. Further study is needed with large number of cattle population with proper AI recording system under veterinary herd fertility programme considering management and environmental variables.