Evaluation of ovsynch protocols for timed artificial insemination in water buffaloes in Bangladesh

Abstract

A total of 65 water buffaloes (groups A, B, and C) at ≥60 days postpartum with a body condition score (BCS) of ≥2.5 were selected to evaluate ovsynch protocols for timed artificial insemination (TAI). The group A buffaloes (n = 25) were treated with a simple ovsynch protocol (GnRH -Day 7 -PGF2α -Day 2 -GnRH -16 h -TAI). The group B buffaloes (n = 22) received PGF2α treatment 12 days before the initiation of simple ovsynch (PGF2α at Day -12 + simple ovsynch; modified ovsynch). The group C buffaloes (n = 18) were treated with a double ovsynch protocol (GnRH -Day 7 -PGF2α -Day 3 -GnRH -Day 7 -GnRH -Day 7 -PGF2α -48 h -GnRH -16 h -TAI). Milk P4 ELISA was used for tracking ovulation and conception rates. Ovulation rates were higher in buffaloes that received the double ovsynch treatment (group C; 83.3%) than those with simple ovsynch (group A; 72.0%; P < 0.05). The group C cows (44.4%) achieved a higher conception rate than the cows of groups A (28.0%) and B (36.4%) (P < 0.05) and multiparous buffaloes having BCS of ≥3.5 responded better to the ovsynch treatments than the primiparous ones (P < 0.05). The double ovsynch protocol increases both ovulation and conception rates in comparison to the simple and modified ovsynch protocols and is more effective in multiparous cows than in primiparous ones.

Studies on Factors Affecting Pregnancy Rate after Treatment of Anestrus Buffaloes in Chitwan District

“…Similar finding was obtained by Devkota et al (2013) who found highest pregnancy rate (37.5%) in buffaloes showing 7-12 months of anoestrus and found lowest pregnancy rate (12.5%) in buffaloes having 2-6 months of anoestrus and >12 months of anoestrus. Similar finding was obtained by Hoque et al, (2014), in cattle in Bangladesh.…”

“…The pregnancy rate was found to be higher in parous buffaloes than heifers when pregnancy was checked in 102 days of FTAI but no significantly different. Similar finding was obtained by Hoque et al, (2014) in cattle in Bangladesh who found highest pregnancy rate (57.4%) in cows of parity 1-2 and lowest pregnancy (45.0%) in cows of parity 0/heifer. However, the variation in pregnancy rates among different parity of cows was not significant (p>0.05).…”

“…But there are other studies showing that conception rate is lower in high milk producer (Nebel and McGilliard, 1993). Hoque et al, (2014) in cattle in Bangladesh found that the pregnancy rate in cows yielding >2-5 L milk was the highest (62.1%) and the pregnancy rate in cows yielding 1-2 L milk was the lowest (49.4%). However, the variation in pregnancy rates among cows of different milk yields was not significant (p>0.05).…”

Effect of Ovsynch Protocol and Mineral Supplementation on Fertility in Pubertal and Peripubertal Buffalo Heifers

“…(Velladurai et al, 2015) observed 37.50 and 25.00 per cent first service conception in mineral mixture and ovsynch plus mineral mixture treated postpartum RFM affected crossbred cows. Similar conception rate were reported by Ravikumar et al, (2007) 33.33 per cent and Hoque et al, (2014) 28 per cent in postpartum cyclic buffaloes treated with ovsynch protocol.…”

“…(Ravikumar et al, 2007) recorded 83.33 and 54.54 per cent ovulatory response in ovsynch treated postpartum subestrus and anestrus buffaloes, respectively. 72 per cent ovulatory response was observed by (Hoque et al, 2014) in postpartum cyclical buffaloes in ovsynch treatment. The reduced ovulatory response observed in mineral mixture group (50.00 percent) could be due to the sequelae of suppressed hypothalamic GnRH and pituitary LH secretion which depressed the ovarian function and in ovsynch treatment for getting good ovulatory response it requires suitable follicular development at the time of initiation of ovsynch and prevention of premature luteolysis (Pursley et al, 1997).…”