@article{breda2013temporary,
  title = {Temporary Calf Removal and Equine Chorionic Gonadotropin (Ecg) Administration after Progesterone-Based Protocol Improves the Reproductive Performance of Beef Cattle},
  author = {Jose Carlos dos Santos Breda and Alisson Morais Giacomeli and Luiz Ernandes Kozicki and Marcio Saporski Segui and Romildo Romualdo Weiss and Ivo Walter dos Santos and Melina Andrea Formighieri Bertol},
  year = 2013,
  url = {https://ibimapublishing.com/articles/IJVMR/2013/781569/},
  journal = {International Journal of Veterinary Medicine: Research & Reports},
  volume = 2013 (2013),
  pages = 7,
  doi = 10.5171/2013.781569,
  abstract = {This study aimed to evaluate the effects of equine chorionic gonadotropin (eCG) administration and the temporary 48-h calf removal (CR) in a long-term progesterone (P4)-based protocol in suckled Nelore cows. In all, 150 cows were randomly submitted to P4 protocol as follows. At day 0 (d 0), an intravaginal device containing 1.9 g P4 was inserted, and 1 mg estradiol benzoate (EB) was injected intramuscularly (im). On d 8, the P4 device was removed, and cows were im injected 500 µg of prostaglandin F group 2 alpha (PGF2α). On the same day, 75 cows (eCGCR group) received 400 IU im of eCG and were separated from their calves for 48 h. The other 75 cows (NoeCGCR group) stayed with the calves and did not receive eCG. On d 10, the calves were returned to the eCGCR group. After 8 days, all the cows were observed for estrus. The ovulatory follicle size was measured using ultrasonography at the day estrus was detected, and artificial insemination (AI) was performed 12 h later. Pregnancy was diagnosed 35 days after AI. The respective parameters for the eCGCR and NoeCGCR groups were as follows: pregnancy rate, 74.6% and 50.6% (p < 0.01); estrus induction rates, 80.0% and 64.0% (p < 0.05); ovulatory follicle diameter, 11.3 and 10.5 mm; estrus observation after d 8, 2.1 and 3.5 days (p > 0.05). Thus, eCGCR after a long-term P4 protocol markedly improved pregnancy rates and estrus induction.  },
  keywords = {Progesterone, eCG, calf removal, estrus observation, AI, Nelore},
  note = Article ID: 781569
}