The present study was developed to evaluate multiparous sow reproductive performance
and back flow in post-cervical artificial insemination (post-CAI) using a reduced number of
sperm than in cervical artificial insemination (CAI). The experimental groups were divided
into sows inseminated by: 1) cervical artificial insemination (CAI): 3×109 spermatozoa/80 ml; 2) post-CAI: 1.5×10spermatozoa/40 ml (post-CAI 1); 3) post-CAI using 1
×
109
spermatozoa/26 ml (post-CAI 2). Post-CAI 1 reproductive parameters were similar to those
of post-CAI 2 (except for live born litter size which was greater in post-CAI 1) and better
than for the CAI group (p < 0.01). In a second experiment the backflow volume, number
of sperm, and sperm quality in the backflow were studied in the 3 experimental groups.
The % of volume and spermatozoa in the backflow was higher in the CAI group (p < 0.05)
than post-CAI groups (statistically similar between them). Moreover, the quality parameters
(motility, progressive motility, viability, chromatin decondensation and morphology)
in backflow semen were identical in all three experimental groups, but differed as regards
the original insemination dose incubated inside a colostomy bag (sperm quality control
group). The present study shows that the use of post-CAI (either post-CAI 1 or 2) in field
conditions can be recommended because the efficiency is similar (in the case of post-CAI
2) or higher (post-CAI 1) than when using the traditional method (CAI), representing a
reduction cost.