Nonsurgical collection of blastocysts from dairy goats.
In two trials, eight attempts were made to collect fertilized ova from dairy goats by nonsurgical methods. In both trials the cervix of each doe was dilated by inserting a Laminaria japonica tent device into the cervical canal prior to flushing. In Trial 1, an attempt was made to collect embryos from four nonsuperovulated does by flushing phosphate-buffered saline (PBS) through a rigid pipette. Little fluid and no embryos were recovered from the does. All four donors were in estrus two days after the procedure. In the second trial, FSH-superovulated does were collected on day 5 following estrus. The donors were anesthetized, and a modified Foley catheter was passed through the cervical canal. In three does, a 24 ga. two-way Foley was stiffened with a size 10 (French) polypropylene catheter which penetrated the Foley, extending 7 cm beyond the tip. Recovery of flushing medium with this device was minimal, and laparotomy of one doe revealed a punctured uterus. Replacement of this device with a different catheter, through which a polypropylene catheter (size 5 Fr.) penetrated only 1 to 2 cm, resulted in satisfactory return of infused PBS, and recovery of two blastocysts and one degenerated ovum from this doe. Use of the same device on a second doe without laparotomy resulted in collection of seven blastocysts and three degenerated ova. Of three observed donors that received Laminaria tents (including one which was not flushed) two were in estrus three days after the procedure, while unused synchronized recipients showed normal cycle lengths. Surgical transfer of two blastocysts from each donor to each of two synchronized recipients resulted in the birth of twin kids from one recipient doe. The study demonstrates the feasibility of embryo collection from dairy goats by nonsurgical means.
Bondurant
R H
RH
Dept. of Veterinary Reproduction, University of California, Davis, CA 95616 USA.
Skirrow
S
S
Anderson
G B
GB
Hanson
F
F
Rogers
W H
WH