Unilateral Intrauterine Horn Insemination of Fresh Semen in Cats.

Abstract

ABSTRACT. The sperm count required were investigated to obtain a conception rate of 80% by unilateral intrauterine insemination (UIUI) of fresh semen in cats. The conception rates obtained by insemination before and after ovulation were also examined. Thirty-six female cats aged 1-7 years were used in the experiments, and the number of experimental cases was 44. Seven male cats aged 2-12 years from which semen could be collected by the artificial vagina method were used. In artificial insemination, 100 iu × 2 or 250 iu of hCG was administered on days 2-4 of estrus, and sperm were introduced into the uterine horn with a greater number of ovulations (or mature follicles) 15, 20 and 30 hr after hCG administration by laparotomy. The inseminated sperm counts were 2 × 10 6 (Exp. 1), 4 × 10 6 (Exp. 2), and 8 × 10 6 (Exp. 3). As a result, ovulation was induced in 42 of 44 cases (induction rate: 95.5%) regardless of the dosage of hCG. Conception was obtained by UIUI in two of 16 animals (conception rate: 12.5%) in the Exp. 1, five of 16 animals (31.3%) in Exp. 2, and eight of 10 animals (80.0%) in Exp. 3. Regarding the relationship between the ovulation state at insemination and conception, the conception rate obtained by insemination before ovulation was clearly higher than that obtained by insemination after ovulation (p<0.05). Regarding the number of kits compared to the number of ovulations on the inseminated side, the percentages of cases in which the number of kits exceeded the number of ovulations on the inseminated side were similar in all groups inseminated with a different number of sperm. It is therefore necessary to investigate conception rates obtained by bilateral insemination to increase the fertility rate. Based on the above findings, it was shown that the sperm count required for fertilization by UIUI is 8 × 10 6 . KEY WORDS: feline, fresh semen, intrauterine insemination.

Approaches and efficacy of artificial insemination in felids and mustelids

“…High pregnancy rates (67-75%) were achieved in ferrets when anesthesia and insemination were conducted at either 24 h post-hCG ($6 h before anticipated ovulation) or the time of hCG administration ($30 h before ovulation). Interestingly, these ferrets were in natural estrus, similar to the cats in the study conducted by Tsutsui et al [66] that demonstrated an 80% pregnancy success. These findings further support the concept that eCG-induced estrus might affect follicular sensitivity to the ovulatory process.…”

“…It was recognized that two semen collection procedures may be required to achieve this high cellular density for a single insemination [65]. In contrast, Tsutsui et al [66,67] achieved a conception rate of 80% in the cat by intrauterine insemination (by laparotomy) but using only 8 Â 10 6 fresh sperm into a single uterine horn. This relationship between insemination site and number of sperm required for conception also has been observed in the dog [68].…”

“…Conversely, when the interval from hCG administration-to-anesthesia is increased to 6-14 h after the anticipated time of ovulation, all cats release ova, and 50% of these become pregnant and deliver live offspring (Table 3) [63]. Tsutsui et al [66] found conflicting results. These investigators evaluated conception rates in domestic cats that were inseminated in utero via laparotomy either before or after ovulation.…”

Unilateral Intrauterine Horn Insemination of Frozen Semen in Cats.

“…However, the semen qualities after thawing were not reported, and thus, we could not evaluate the extender used in their study. Therefore, we prepared frozen feline semen using egg yolk fructose citric acid (EYT-FC) [6,7], which we use as an extender for fresh feline semen, and egg yolk sodium citrate (EYC), which is an extender of bovine semen [4], and compared the semen quality after thawing and the conception rate obtained by UIUI. To ensure uniform conditions for the freezing method, a cell freezer (Cell Freezer R204, England) was used.…”

“…To ensure uniform conditions for the freezing method, a cell freezer (Cell Freezer R204, England) was used. For AI, UIUI was performed, as reported [7] for insemination of fresh semen, and we investigated the fertilization of ova in the non-inseminated uterine horn by the inseminated sperms. Because a higher conception rate was previously obtained by insemination before ovulation than insemination after ovulation, AI was performed 15 or 20 hr after hCG administration, a time point predicted to be prior to ovulation [7].…”