Trans-abdominal scan evidence of superfoetation in a West African Dwarf goat doe: A case report
Twelve adult West African Dwarf (WAD) goats consisting 3 bucks and 9 does were used in a study which investigated the response of the does to standing heat and mating after synchronization with Lutalyse ®. The bucks were kept in a separate pen from that of the does. All animals were fed with commercial feedstuff (15.23% CP), elephant grass and fresh water ad libitum. One of the does which had earlier been observed to be mated during 72-96 hours following synchronization was again observed to stand and be re-mated during 192-216 hours. Trans-abdominal scan conducted at 60 days post initial mating revealed the presence of two conceptuses with Crown Rump Lengths (CRLs) measuring 2.0 cms i.e. about 42.6 days gestation and 3.7 cms i.e. about 65.9 days gestation. This finding does not only show that WAD does may return to estrus shortly after an initial mating, but showed a difference of about 23 days in the ages of the conceptuses. This finding may suggest a delay in implantation of the younger embryo, if the two or more ova were fertilized during the first mating exercise, or that the younger embryo was conceived sequel to the 192-216th hour-mating. Either-way, this observation is suggestive of superfoetation.
Keywords: Mating, implantation, West African Dwarf (WAD) does, ultrasonography, superfoetation.