PREVENTION OF TRANSMISSION OF SHEEP PULMONARY ADENOMATOSIS BY EMBRYO-TRANSFER

Two-hundred-and-fifteen embryos recovered from 76 donor ewes from floc ks endemically infected with sheep pulmonary adenomatosis (SPA) and ma ted with uninfected rams were transferred to 131 uninfected recipients under strict sanitary conditions using International Embryo Transfer Society protocols. The recipients and their progeny were kept in a clo sed, isolated spa-free flock. Thirty-eight of 51 progeny from SPA-posi tive donors and 55 of 74 progeny from donors in which no lesions of SP A were detected survived for at least five years after birth. In a sim ilar study 11 embryos from four uninfected donors mated to an SPA-infe cted ram were transferred to seven recipients, and four of five progen y born to four recipients survived for at least five years. No evidenc e of SPA was found in the recipients or their progeny by embryo transf er in either study. On the basis of clinical and pathological criteria , it is concluded that embryo transfer can be used to provide an effec tive barrier against the transmission of SPA from donors from infected flocks, whether or not the parents show clinical signs of the disease .