Laparoscopic Oviductal Artificial Insemination Improves Pregnancy Success in Exogenous Gonadotropin-Treated Domestic Cats as a Model for Endangered Felids1

Abstract

Artificial insemination (AI) in cats traditionally uses equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG) to induce follicular development and ovulation, with subsequent bilateral laparoscopic intrauterine insemination. However, long-acting hCG generates undesirable secondary ovulations in cats. Uterine AI also requires relatively high numbers of spermatozoa for fertilization (~8 × 10(6) sperm), and unfortunately, sperm recovery from felids is frequently poor. Using short-acting porcine luteinizing hormone (pLH) instead of hCG, and using the oviduct as the site of sperm deposition, could improve fertilization success while requiring fewer spermatozoa. Our objectives were to compare pregnancy and fertilization success between 1) uterine and oviductal inseminations and 2) eCG/hCG and eCG/pLH regimens in domestic cats. Sixteen females received either eCG (100 IU)/hCG (75 IU) or eCG (100 IU)/pLH (1000 IU). All females ovulated and were inseminated in one uterine horn and the contralateral oviduct using fresh semen (1 × 10(6) motile sperm/site) from a different male for each site. Pregnant females (11/16; 69%) were spayed approximately 20 days post-AI, and fetal paternity was genetically determined. The number of corpora lutea (CL) at AI was similar between hormone regimens, but hCG increased the number of CL at 20 days post-AI. Numbers of pregnancies and normal fetuses were similar between regimens. Implantation abnormalities were observed in the hCG group only. Finally, oviductal AI produced more fetuses than uterine AI. In summary, laparoscopic oviductal AI with low sperm numbers in eCG/hCG- or eCG/pLH-treated females resulted in high pregnancy and fertilization percentages in domestic cats. Our subsequent successes with oviductal AI in eCG/pLH-treated nondomestic felids to produce healthy offspring supports cross-species applicability.

Urethral catheterization and sperm vitrification for simplified semen banking in felids

“…With LO‐AI, sperm function and motility over time are not as critical as with intravaginal or uterine AI. High pregnancy rates (70%–80%) have been obtained with LO‐AI using low sperm numbers (~1 million motile/oviduct) for insemination, including semen that was frozen using standard straw cryopreservation methods (Swanson, ; Conforti et al., ; Swanson, Newsom, Lyons, Grahn, & Bateman, ). The results of the present study suggest that catheter‐collected vitrified sperm exhibit adequate post‐thaw sperm function to produce pregnancies in domestic cats if used in conjunction with LO‐AI.…”

The use of altrenogest to avoid hyperestrogenism after eCG-hCG ovulation induction in southern tigrina (Leopardus guttulus)

“…Increased concentrations of estrogen during surges are proven to be detrimental to oocyte quality [24], as these create an unsuitable uterine environment for fertilization and implantation [25] as well as disrupt oviductal embryo transport [26]. In theory, longer estrogen exposure could also have deleterious effects on reproduction [27].…”

“…Therefore, preventing excessive estrogen surge lengths to a more natural duration might also improve fertility rates after gonadotropin ovulation induction [15,27]. One approach for preventing excessive estrogen and progesterone circulation in felids under exogenous gonadotropin regimes is to focus on improving these protocols, testing different gonadotropins, i.e., porcine LH instead of hCG [27,28].…”

“…One approach for preventing excessive estrogen and progesterone circulation in felids under exogenous gonadotropin regimes is to focus on improving these protocols, testing different gonadotropins, i.e., porcine LH instead of hCG [27,28]. Another approach is to reduce to minimum endogenous hormonal production before using established eCG-hCG or gonadotropin protocols and dosages [14,15].…”

Spermatic and oxidative profile of domestic cat (Felis catus) epididymal sperm subjected to different cooling times (24, 48 and 72 hours)

“…Therefore, it is necessary to improve alternatives for reproduction and preservation for these animals (Wildt et al., ). Recent advances in oocyte cryopreservation (Fernandez‐Gonzalez & Jewgenow, ), intracytoplasmic sperm injection (ICSI) (Buarpung, Tharasanit, Comizzoli, & Techakumphu, ), semen cooling (Angrimani, Barros, et al., ) and artificial insemination (Conforti et al., ) are practical examples of progress in feline reproduction methods. Even though several studies are focused on the gamete function of the domestic cat, the results can be applied also to wild felines as the domestic feline assumes an important role as a biological model to wild cats (Buarpung et al., ).…”