Synchronization and Resynchronization as a Novel Approach for Improving Reproductive Performance of Postpartum Dairy Cows
A.H. Shahzad1, A. Sattar1,*, A. Husnain1, I. Ahmad2, N. Ahmad1, D. Nak3 and Y. Nak3
1Theriogenology Department, University of Veterinary and Animal Sciences, Lahore
2Physiology Department, University of Veterinary and Animal Sciences, Lahore
3Department of Obstetrics & Gynecology, Uudag University, Bursa, Turkey
* Corresponding author: masattar@uvas.edu.pk
Fig. 1.
Scheme of the estrus synchronization protocols in experiment 1. Cows in resynch group were synchronized by CIDR-EB (CIDR on day-10, PG on day-6, Estradiol Benzoate (EB) on day-2. CIDR withdrawal on day-7, TAI 48 h later was marked on day-0). On day 14 post TAI previously used autoclaved CIDR was inserted for 7 days. On 23rd day post TAI GnRH was injected intramuscularly. Pregnancy diagnosis was done on day-30. In non-pregnant PG (Dalmazin, d-cloprostenol 0.150 mg; Fatro, Italy) was injected. GnRH (Dalmareline, lecirelin, Fatro Italy) after 48 h and TAI 16-20 h post GnRH. BS=blood sampling on day 14, 16 and 30 post TAI. CL area on day 30 post TAI. In control group (CIDR-EB) lactating dairy cows (n = 70) were enrolled without further treatment except AIDE (artificial insemination at detected estrus) between 18 to 30 days post TAI and PD was performed 30 days after AI, respectively.
Fig. 2.
Scheme of the estrus synchronization protocols in experiment 2. Cows in resynch group (n = 54) were synchronized by CIDR-EB (CIDR on day-10, PG on day-6, Estradiol Benzoate (EB) on day-2. CIDR withdrawal on day-7, TAI 48 h later was marked on day-0). On day 14 post TAI when previously used autoclaved CIDR was inserted for 7 days. On 23rd day post TAI injection of GnRH was injected intramuscularly. Pregnancy diagnosis was done on day-30. In case of non-pregnant PG (Dalmazin, d-cloprostenol 0.150 mg; Fatro, Italy) was injected. GnRH (Dalmareline, lecirelin, Fatro Italy) after 48 h and TAI 16-20 h post GnRH. In control group (CIDR-EB) lactating dairy cows (n = 64) were enrolled without further treatment except #AIDE (artificial insemination at detected estrus) between 18 to 30 days post TAI and PD was performed 30 days after AI, respectively.