The study was designed to determine the effects of breed, age, parity, feeding practice, Body Condition Score (BCS), timing of insemination, postpartum insemination interval and milk yield on first service pregnancy rates in cows (n = 308). The demographic factors were recorded by interviewing the farmers. All cows were examined for pregnancy diagnosis by rectal palpation of genital tract at 60-80 days post Artificial Insemination (AI). The pregnancy rate of different groups was compared and analyzed by Z test using SPSS software version 17. The overall pregnancy rate in cows was 52.6%. Though the age and parity of cows and milk yield did not affect significantly on pregnancy rate, the pregnancy rate was the highest in cows of 3-5 years of age (56.1%), in cows of parity 1-2 (57.4%) and in moderate yielding (2-5 liters milk/day) cows (62.1%). Balanced feeding and timing of insemination had a profound impact on the pregnancy rate of cows. The pregnancy rate in cows fed with combination of green grass, straw and concentrate was significantly (p<0.05) higher (63.5%) than cows fed only straw (38.5%). The pregnancy rate in cows with BCS 3-4 was significantly (p<0.05) higher (58.0%) than that of BCS 1.5-2 cows (35.0%). The pregnancy rate in cows inseminated at 6-12 h after the start of standing estrus was significantly (p<0.05) higher (58.8%) than those inseminated 13-24 h after start of standing estrus (40.4%). Cows with good BCS and AI at 6-12 h after the start of standing estrus are the best choice of selection for getting the best result in the first service pregnancy rate in cows.

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