Fertilization rate after deep intra uterine insemination in pig

The objectives of the present study were to investigate fertilization rate and number of embryo on each side of the reproductive tract after inseminated multiparous sows using deep intra uterine insemination (DIUI) technique with fresh semen. Eight crossbred multiparous sows were used in the experiment. The sows were examined for the onset of standing oestrus every 6 h by using a back pressure test in the presence of a mature boar. Transrectal ultrasonography was performed every 4 h using a 5 MHz probe to examine the time when ovulation took place in all sows. During the second oestrus after weaning, the sows were inseminated once at about 6-8 h before expected ovulation using diluted fresh semen from a proven sire. The insemination was performed using DIUI technique. The long flexible catheter (1.8 m) was inserted through the conventional artificial insemination (AI) catheter and was moved forward along one uterine horn until its total length. The diluted fresh semen with 150x106 motile sperm in 5.0 mL Beltsville thawing solution (BTS) was deposited at the proximal third in one side of the uterine horn (unknown side). Subsequently, a warm BTS 2.5 mL was used to flush the semen into the uterine horn after insemination. All sows (n=8) were generally anesthetized at about 61.1±12 h after insemination (range 48-72 h). The embryos were flushed from the oviduct and the proximal part of the uterine horn. The number of embryos and number of ovulation on the left and right sides of the reproductive tract within animal were compared using pair t-test. It was found that fertilization was found in 5 out of 8 sows (62.5%) after DIUI. On average, 11.2±2.2 embryos/sows were recovered from both sides of the reproductive tracts. The number of ovulation per sows was 16.4±2.6 ova. The number of ovulation on the left and the right side of the ovaries did not differ significantly (8.5 vs 7.9; P=0.75). Of the 5 pregnant sows, 57 embryos were recovered. Of these embryos, 3 embryos developed to 8-cell stages (5.3%) and 54 embryos developed to 4-cell stages (94.7%). Number of embryos recovered from the left and the right side of the reproductive tracts were not significantly differences (left-right =+4.2, P=0.20). The overall recovery rate of the oocytes and embryos was 66.4% (87/131). Fertilization rate in all pregnant sows was 100% (all ovum were fertilized). It could be concluded that using DIUI technique in pig with 150x106 spermatozoa, fertilization took place in both side of the oviducts.