119 Use of lactating females with nursing calves as recipients in an embryo transfer program in camel (Camelus dromedarius)

Multiple ovulation and embryo transfer (MOET) has been used to improve the reproductive efficiency of elite camels. However, one of the most challenging factors for the use of this technology is the availability and selection of good-quality recipients. The best pregnancy rates are achieved when embryos are transferred to recipients that are negatively synchronized to be 1 or 2 days behind the donor. In Middle Eastern countries, calves are allowed to suckle for about a year and are weaned usually during the later months of the breeding season. This way the dam loses a year of nursing the calf and is available for breeding or as a recipient in a MOET program during the next season. The present experiment was, therefore, aimed to study the use of lactating camels as recipients in our MOET program while allowing their calves to suckle them till weaning, which was ~3 months after embryo transfer. A total of 25 lactating animals were selected and their ovaries were scanned by ultrasound. The animals with no follicular activity were injected with 1000 IU of equine chorionic gonadotrophin (eCG) intramuscularly to induce ovarian activity and follicular growth. On Day 8 after eCG administration, all recipients were scanned, and those having mature follicles were injected with gonadotrophin-releasing hormone (GnRH) to induce ovulation. Out of 25 animals, 18 animals (72%) responded and had follicles more than 10 mm in diameter on either ovary on Day 8, which were given an injection of GnRH to induce ovulation. All 18 animals ovulated and had CL as seen on Day 7 after GnRH administration. Each recipient received a single freshly collected embryo in the left uterine horn on Day 7 after their ovulation. Twenty recipients from the weaned/nonlactating ones were also synchronized, as per our previously published protocols, and received each a freshly collected embryo, to act as the control. On Day 15 after embryo transfer 14 of the lactating recipients (78%) were detected as pregnant by ultrasound scanning and 11 (61%) of them were pregnant by Day 90. All of these recipients are in the advanced stage of pregnancy and expected to deliver within the next 2 months. Our results of pregnancies achieved in lactating camels were not different from those of nonlactating camels (60%) on Day 90 after embryo transfer. In conclusion, this study shows that lactating camels can be used as recipients in an embryo transfer program while they are with their suckling calves and their pregnancy rates are at par with the nonlactating recipients.