INFECTION OF LACTATING GOATS BY MAMMARY INSTILLATION OF CELL-BORNE CAPRINE ARTHRITIS-ENCEPHALITIS VIRUS

The possibility of transmission of caprine arthritis-encephalitis viru s between lactating goats by the transfer of infected cells during mil king has been examined experimentally. Four virus-free Saanen goats we re infected, two in full lactation and two during the drying off perio d, by instillation of infected allogeneic cells into the milk canal of one-half of the udder. All four goats became infected, as shown by th e isolation of virus from peripheral blood monocytes, seroconversion, and presence of typical lesions in the mammary gland. The virus was ra pidly and constantly demonstrable in cells from the mammary secretions of the dry goats, but less regularly detected from milk cells from th e lactating goats. Virus was more frequently isolated when milk SCC we re elevated. Virus was present as often in secretions from the uninocu lated half of the udder as the inoculated half. Dry goats seroconverte d progressively, although antibody concentrations remained low; the la ctating goats developed weak, positive Western blots in the late phase of lactation but only gave positive ELISA titers after drying off and artificial reinduction of lactation. At necropsy, lesions typical of the virus were observed in the mammary tissues of all four goats, and three had arthritis of the carpi.