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Embryo production by superovulation and dual siring in alpacas (Vicugna pacos)

Forshey, B.S., Moraes, C.R., Lakritz, J., Pinto, C.R.F., Coffman, E., Schanbacher, B.J., Place, N.J., Coutinho da Silva, M.A.
Small ruminant research 2018 v.162 pp. 63-68
Vicugna pacos, alpacas, embryo (animal), embryo transfer, females, follicle-stimulating hormone, genetic improvement, herds, male fertility, males, ovarian follicles, ovulation, parentage, progeny, superovulation
Alpacas can only produce one offspring per year. In order to accelerate the genetic gain of a herd, superovulation and embryo transfer can be used to produce multiple embryos from superior females. We hypothesized that the use of dual siring with superovulation would result in the production of multiple embryos sired by different males. After administration of the superovulation protocol, receptive females were bred to two proven males (A and B) 8–12 h apart and ovulation was induced by gonadotropin at the time of the first breeding. Growth of multiple dominant follicles was successfully achieved in 95% of cycles. Females that were receptive after FSH treatment and were bred with both males (order A–B or B–A). Embryo collections were performed 8–9 days post-breeding on 15 cycles and 73% of collections recovered ≥1 embryo. A total of 46 embryos, were recovered for an average of 3.13 ±3.1 (range 0–10) embryos/flush. Parentage analysis was performed for 23 embryos (6 from A to B, 17 from B to A). Twenty-two of the 23 embryos were determined to be sired by male B, being six embryos from breeding A-B and 16 embryos from breeding B-A. A single embryo from breeding B-A was sired by male A. In conclusion, FSH administered at decreasing doses can be used to promote superovulation resulting in collection of multiple embryos per cycle. However, slight differences in male fertility may affect the frequency of embryos sired by each male.