Table 2.
Ovulation, conception, and pregnancy rates of suckled Bos indicus cows submitted to a synchronization of ovulation protocol using progesterone associated with estradiol having different dosages of PGF2α (Study 1), ovulatory stimuli (Study 2), and uses of intravaginal progesterone insert (Study 3 and 4). Adapted from Meneghetti et al. [17].
| Item | Ovulation rate | Conception rate | Pregnancy rate |
|---|---|---|---|
| Study 1-PGF2α dosagea | |||
| Half-dose | 88.7% (110/124) | 69.2% (76/110) | 61.3% (76/124) |
| Full-dose | 94.4% (119/126) | 68.2% (81/119) | 64.3% (81/126) |
| Study 2-Ovulatory stimulusb | |||
| ECP | 89.5% (282/315) | 56.7% (160/282) | 50.8% (160/315) |
| EB | 90.9% (289/318) | 57.1% (165/289) | 51.9% (165/318) |
| GnRH | 91.0% (284/312) | 59.5% (169/284) | 54.2% (169/312) |
| Study 3-CIDR usesc | |||
| CIDRn | 91.7% (496/541) | 56.0% (278/496) | 51.4% (278/541) |
| CIDR9d | 90.6% (482/532) | 59.3% (286/482) | 53.8% (286/532) |
| CIDR18d | 90.1% (373/414) | 55.8% (208/373) | 50.2% (208/414) |
| Study 4-CIDR usesc | |||
| CIDRn | 79.7% (55/69) | 54.5% (30/55) | 43.5% (30/69) |
| CIDR9d | 80.0% (144/180) | 61.1% (88/114) | 48.9% (88/180) |
| CIDR18d | 83.9% (188/224) | 60.1% (113/188) | 50.4% (113/224) |
| CIDR27d | 85.7% (90/105) | 57.8% (52/90) | 49.5% (52/105) |
aCows were treated with 12.5 mg (Half-dose) or 25 mg (Full-dose) dinoprost tromethamine on d 7 of a protocol using progesterone associated with benzoate estradiol. Progesterone devices were maintained between d 0 and 9, and fixed-time AI were performed on d 11. Ovulation was induced with estradiol benzoate administered on d 10. Dependent variables were not affected by PGF2α dosage (P > .10).
bCows were treated with estradiol cypionate (ECP) on d 9, estradiol benzoate (EB) on d 10, or gonadotropin releasing (GnRH) hormone on d 11 relative to initiation of a protocol using progesterone associated with benzoate estradiol. Progesterone devices were maintained between d 0 and 9, and fixed-time AI were performed on d 11. Dependent variables were not affected by ovulatory stimulus (P > .10).
cCows received a nonpreviously used CIDR (CIDRn), a CIDR used previously for 9 d (CIDR9d), a CIDR used previously for 18 d (CIDR18d), or a CIDR used previously for 27 d (CIDR27d) at initiation of the protocol. Dependent variables were not affected by CIDR type (P > .10).