Adoption Of Embryo Transfer In Kenya And Its Improvement Through Use Of Optimal FSH Dosage During Superovulation

Abstract

Agriculture is a key sector in national development contributing 32% of the gross domestic product (GDP) in Kenya. The livestock sub sector accounts for 37% of the agricultural GDP equivalent to 12% of the national GDP with dairy cattle contributing 4% of the national GDP. Dairy farmers in Kenya are required to embrace assisted reproductive techniques like embryo transfer (ET) to meet an ever-rising demand for milk that is projected to rise to 12.76 billion litres annually by the year 2030. Although ET has been in this county for decades, its practice has not been optimal to meet the demand of the need to improve dairy cattle through production of high quality heifer stock. The major challenge the ET practitioners have been citing for its inefficiency have been low embryo output during flushing and the cost of superovulation due to dosage of Follicle Stimulating Hormone (FSH). This study sort to utilize ultrasonography to create an understanding of the follicular dynamics during superovulation in order to enhance adoption of ET through reduced dosage rate of FSH. The specific objectives of the study were to evaluate the follicular dynamics during super ovulation using different follicle stimulating hormone (FSH) dose rates, to determine the embryo yield (quantity and quality) for the different FSH superovulation dose rates, to assess any other general factors likely to affect adoption of embryo transfer technology in Kenya, and to analyze the success rate of currently used MOET protocol used on dairy cattle in Kenya in relation with regards to embryo yield. The research was carried out in dairy cattle kept at the University of Eldoret farm in Uasin Gishu County. Cows were restrained in a crush and ultrasonography was done using a portable ultrasound device equipped with a 5.0/7.5 MHz linear bi-frequential probe (frequency of 6.5 MHz was used as standard). These were done daily before superovulation in three consecutive estrous cycle repeats. The probe was secured in an examination sleeve to protect the diaphragm and also to hold the acoustic gel in place. The probe was then introduced into the rectum after fecal evacuation was done and moved back and forth over the pelvic area to scan the ovaries xiii from above. Follicles of different sizes and the CL were identified and their location on the ovaries was noted. The diameters of the three largest follicles and corpus luteum (CL) were then measured and their location sketched on a research book to ease their identification. These follicle traits were used to track and evaluate for follicular dynamics. Follicular populations were obtained by manual count of all visible follicles. Numbers and sizes of ovarian follicles were determined and follicles were considered small (2 to 5 mm) or medium (6 to 8 mm). The dominant follicle (DF) of a wave was defined as the follicle that measured at least 9 mm in diameter and exceeded the diameter of all other follicles in the wave. The estrous cycles were described as being in recruitment, selection or dominant phase based on numbers and sizes of follicles noticed in the ovary. Cows observed to be in either recruitment or selection phases of the estrous cycle were super ovulated and later inseminated twice at 12 hours apart and embryos flushed after seven days. Numbers and grades of the harvested embryos were assessed. A questionnaire was also administered to 293 farmers in Uasin Gishu and Trans Nzoia Counties to evaluate factors affecting adoption of MOET technology. Secondary data from ADC Namandala and Sasini farms retrieved and analyzed to success rate of the currently used MOET protocol. Cows were seen to be in the three phases of estrous cycle during superovulation hence the usefulness of ultrasonography during superovulation. One third of the donors failed to ovulate, another third produced 1 – 3 embryos while a third produced over three embryos. The number of embryos recovered after flushing was similar to those of the MOET protocol conducted in Sasini farm but more than those for ADC Namandala farm. The season, technique, super ovulation protocol used and animal factors were shown to influence embryo production and recovery. The low adoption of embryo transfer was associated with inadequate sensitization about the technology, unavailability of the technology in Kenya, high cost of embryo production, and few professionals trained to handle the process. A FSH dosage rate of 200mg produced similar results to that of 400mg. To reduce the cost of embryo production xiv associated with the use of 400 mg of FSH per donor, it is recommended that super ovulations may be carried out in Kenya using 200 mg of FSH per donor. Ultrasound technique should also be used to monitor dynamics of follicular activity in order not to waste FSH on animals in the dominant phase who will not respond. Once this is done adoption of ET in Kenya is likely to be enhanced.