Factors Limiting the Pregnancy Rates in Artificially Inseminated Cows in Bangladesh

Abstract

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.

Risk factors limiting first service conception rate in dairy cows, and their economic impact

“…We observed that FSC rates were similar between the two farms studied, which is probably because they have similar nutritional and health management, and productivity. Our finding that cow parity does not affect FSC is consistent with those of some studies [ 4 , 19 ], but others have shown that FSC rate is affected by cow parity because it was lower in cows with parity ≥4 or 5 than in primiparous cows [ 7 , 10 ]. IDE or timed AI did not affect FSC rate in the present study, which is consistent with some previous studies [ 27 , 28 ].…”

“…Cows with BCS≤2.25 were less likely to conceive at first service than cows with BCS ≥3.25 in a previous study [ 18 ]. In addition, the FSC rate was lower in cows with BCS of 1.5 to 2.0 than in cows with BCS of 3 to 4 in another [ 19 ], and FSC rate was higher in cows with BCS of 2.5 to 3.5 than in cows with BCS of 1.5 to 2.0 at the time of AI [ 3 ]. These findings indicate that nutritional status at the time of AI is very important for FSC and also imply that excessive BCS loss in early lactation should be recovered before performing AI.…”

Assessing Reproductive Performance to Establish Benchmarks for Small-Holder Beef Cattle Herds in South Africa

“…The overall annual PR reported at both national and provincial level was comparable with those reported in Bangladesh, Brazil and SA [ 21 , 40 , 41 ]. This level of performance is lower than the >75% recommended achievable performance of PR for beef cattle at extensive systems in tropical regions such as Australia [ 39 , 42 , 43 ].…”

Blood Biochemical Profiles and Pregnancy Rate of Brahman Crossbred Cows Supplemented with Mineral Mixture

“…The results obtained were similar to Ervandi et al (2020) that Brahman Crossbred cows fed low-quality feed will produce a low pregnancy rate. Haque et al (2015) also suggested that the variety of feed given to breeding cows (fresh forage, straw and concentrate mixture) increased reproductive hormone, resulting in a better pregnancy percentage. In this study, early detection of pregnancy was assumed to be using 21-NRR.…”