Deep intrauterine insemination in sow: results of a field trial

摘要

Riassunto Traditional insemination techniques in pigs depose a high number of spermatozoa (2 to 3x109 spermatozoa) in a large volume of liquid (80-100 ml) into the cervix channel. The dose can be reduced markedly deposing it directly into the uterine horn. Previous studies showed that fertility rate and litter size were not significantly different with 5 or 15x107 spermatozoa in 10 ml into the uterus. The goal of this study was to determine the on-farm application and the reproductive performance of the deep intrauterine insemination (Firflex? probe, MAGAPOR, Spain) in sows. Experiments were conducted under field conditions in 4 commercial pig farms in the North of Italy (September 2003 and March 2004). A total of 166 crossbred multiparous sows were randomly selected after weaning and assigned to one of the following groups: Group 1 – traditional insemination with 3x109 sperm./dose, two insemination per oestrus (n=94) and Group 2 – deep intrauterine insemination with 15x107 sperm./dose, one insemination per oestrus (n=72). Different technicians in each farm performed the inseminations. Fertility rate was verified by transcutaneous ultrasonography; the total number of born and the number of alive born were counted at farrowing. Analysis of variance using the GLM procedure of SAS (SAS/STAT, 2000) was used to determine the effect of insemination technique, parity, period, farm and their interaction on the main effects of fertility rate and litters size. Fertility rate of Group 2 (50.5%) was significantly lower (P≤0.01) than those achieved after a traditional insemination (77.8%). The interaction between the insemination group and the period of trial was significant (P≤0.01), pointing out increasing results during the second period for deep intrauterine insemination. Prolificacy was significant lower (total born, P≤0.05, and born alive, P≤0.01) for Group 2. In conclusion, the results indicate that deep intrauterine insemination might realize suitable results with respect of fertility, even if the adverse effects on prolificacy will need to be further tested. The potential advantage for the pig industry occurs if technicians acquire the specific practice.