Development of a large commercial camel embryo transfer program: 20 years of scientific research.

Embryo transfer in camels was initiated to respond to demand from the camel industry particularly in the United Arab Emirates since 1990. This paper reviews the research performed in critical areas of reproductive physiology and reproductive function evaluation that constitute a pre-requisite for a successful embryo transfer program. A description of donor and recipient management as well as a retrospective evaluation of calf production in the embryo transfer program at Sweihan, UAE is provided. The program utilized two management systems for donors, with and without ovarian superstimulation. Non-stimulated donors are flushed every 14-15 days with a mean embryo production per year per female of 8.5±3.1 (mean±SEM). Response to gonadotropin stimulation is extremely variable. FSH doses and frequency of administration is often adjusted to a specific female. In the period of 1990-2010, 11,477 embryos were transferred to recipients. Transfers from 1990 to 2009 (n=10,600) resulted in 2858 weaned calves, representing an overall efficiency (% weaned calves/transfer) of 27%. Pregnancy rates at 60 days post transfer varied from 19 to 44%. Pregnancy length following transfer is extremely variable. A major challenge in a large embryo transfer program is finding good quality recipients. Causes of pregnancy and neonatal losses are under study.