Progesterone (P4) has a pivotal position on feminine puberty attainment in most cattle. Nevertheless, there aren’t any research evaluating the impact of P4 remedy beforehand to boar publicity for puberty induction in gilts.

Strategies and outcomes: Serum P4 focus, estrus expression and reproductive efficiency after boar stimuli have been evaluated in gilts intramuscularly handled with long-acting P4 earlier than boar publicity. In Experiment I, prepubertal gilts acquired both 1 mL of saline (management) or intramuscular P4 remedy (150 mg, 300 mg or 600 mg; n = 6 per remedy). Serum P4 focus for P4-treated gilts was higher than for management gilts for at the very least 8 d for P4300 and P4600 teams, however higher till after 16 d just for these handled with 600 mg. In Experiments II (prepubertal) and III (peripubertal), gilts acquired both saline (management) or 300 mg P4 intramuscular and people exhibiting estrus indicators have been artificially inseminated, whereas gilts with out estrus expression have been culled. In prepubertal gilts (Exp. II), estrus expression fee didn’t differ for management (79.1%; n = 110) and P4-treated gilts (81.5%; n = 108). In peripubertal gilts (Exp. III), though estrus expression didn’t differ between management (77.6%; n = 106) and P4-treated (69.6%; n = 102) gilts, P4-treated gilts introduced longer (23.1 ± 1.4 days) interval from remedy to estrus expression than management gilts (17.1 ± 1.3 days). In Experiments II and III, the proportion of culled gilts with ovarian buildings in line with regular estrous cycles, farrowing fee, and litter dimension didn’t differ between therapies.

Conclusion: Intramuscular remedy with 300 or 600 mg of long-acting P4 was environment friendly in sustaining excessive P4 concentrations in prepubertal gilts for at the very least 8 days. Nevertheless, P4 remedy over this time interval didn’t profit the reproductive efficiency of prepubertal and peripubertal gilts.

Baldessar P, de Brito CRC, Johann H, Schultz C, Peripolli V, Moreira F, Lucia T, Ulguim RR, Gasperin BG, Bianchi I,
Lengthy-acting injectable progesterone remedy previous to puberty induction in gilts. Home Animal Endocrinology. 2023; 84–85: 106807. https://doi.org/10.1016/j.domaniend.2023.106807.