Eficiência reprodutiva com inseminação artificial intra-cervical e pós-cervical, em fêmeas suínas, associada à concentração espermática e perfil estral

Abstract

Artificial insemination (AI) is a technique intensively used in the swine farms nowadays, due to its benefits related to genetic improvement and health status, allowing the industry to market high-quality healthy products. The post-cervical AI (PCAI) allows the deposition of semen in the uterine body, using 1 x 10 9 spermatozoa dose. Thus, with PCAI the fertility of one particular boar can influence the reproductive performance of a much higher number of females than in ICAI-based systems. The objective of this study was to compare the subsequent reproductive performance of swine breeding females submitted to either intra-cervical artificial insemination (ICAI) with sperm concentrations of 3.5 x 10 9 spermatozoa per dose or post-cervical artificial insemination (PCAI) with 2, 1, or 0.5 x 10 9 spermatozoa per dose. The study was conducted in a commercial farm including 338 F1 females. Among them, 232 were first inseminated 12 h after estrus detection, receiving the subsequent doses after 12 h intervals, whereas 106 were inseminated right after ovulation diagnosis through real-time ultrasound. Conception and farrowing (FR) rates for ICAI (98.9% e 97.9%, respectively) did not differ (P < 0,001) from those observed for PCAI (87.1% e 84.3%, respectively). Total litter size did not differ across treatments (P = 0.09). Although TP did not differ (P = 0,40) for different parities, total litter size for primiparous females (9.1 ± 0.4) was lower (P = 0,0004) than for parity-2 and -3 females (11.5 ± 0.5 e 11.5 ± 0.2, respectively). There was a significant effect of an interaction between treatment and parity on total litter size (P < 0.05), generally characterized by the occurrence of lower litter sizes for PCAI in primiparous females than for other treatment by parity combinations. In conclusion, reproductive performance for PCAI and ICAI were similar with sperm concentrations up to 1 x 10 9 spermatozoa per dose.