Evaluation of Ovsynch and CIDR inserted concurrently with or two days after initiation of Ovsynch protocol to improve reproductive performance in lactating dairy cows with low estrus detection efficiency


Shahzad A. H., Sattar A., Ahmad N., Ahmad I., Nak D., Nak Y.

ADSA- ASAS Joint Annual Meeting , Florida, Amerika Birleşik Devletleri, 12 - 16 Temmuz 2015, ss.874

  • Yayın Türü: Bildiri / Özet Bildiri
  • Basıldığı Şehir: Florida
  • Basıldığı Ülke: Amerika Birleşik Devletleri
  • Sayfa Sayıları: ss.874
  • Bursa Uludağ Üniversitesi Adresli: Evet

Özet

To assess the efficiency of 3 synchronization methods as postpartumreproductive management tools in dairy cattle on a commercial dairyfarm. Cyclic Holstein lactating cows (n = 167),55–90 DIM, were ran-domly allotted to 1 of 3 treatments. First group was (Ovsynch: n = 58)given a 2-mL i.m. injection of synthetic GnRH on d 0. After 7 d, PGF2a(2 mL i.m.) was injected. A second injection of GnRH was administered48 h after the PGF2a injection and all cows were bred by timed AI 16 hafter the second GnRH injection. Cows in second group (Ovsynch+P7:n = 55) were introduced a modified Ovsynch TAI treatment similar toOvsynch but CIDR was inserted for a 7-d period (CIDR was insertedwith GnRH and removed on PG Shot). In third group (Ovsynch+P5; n= 54), cows were subjected to Ovsynch protocol in addition to CIDRinsertion for 5 d (CIDR was inserted after 2 d of GnRH and removed withPG shot). P4 conc. was measured on d 30 and 60. Pregnancy diagnosiswas carried out at d 30, 60, 90 post insemination in all 3 groups. Pro -gesterone profile was significantly higher (P < 0.05) for Ovsynch + P5(7.75 ± 0.38 ng/mL) and Ovsynch + P7 (7.58 ± 0.26 ng/mL) comparedwith Ovsynch (6.52 ± 0.32 ng/ mL) on d 30 PTAI but nonsignificantamong all 3 synchronization treatments (i.e., 6.37 ± 0.49 in Ovsynch,6.75 ± 0.36 in Ovsynch+P5 and 6.80 ± 0.41 in Ovsynch+P7 group).Pregnancy rate in Control group was 39.7, 36.2, and 32.80 on d 30,60 and 90 post insemination. In second modified Ovsynch group with7d CIDR (Ovsynch+P7) insertion pregnancy rate was 42.6% on d 30,37% on d 60 and 90 PAI. In third group pregnancy rate was 45.5, 43.6and 41.8 on corresponding 30, 60, 90 d PAI. Although pregnancy ratewere statistically not significant but, by percentage points, improvedpregnancy rate was observed on all 3 time points in Ovsynch+p5 group.