Experimental Transmission of Enzootic Intranasal Tumors of Goats

The successful experimental transmission of enzootic intranasal tumor (EIT) from goat to goat is described. Ten kids, less than 48 hours old, from a Hock free of the disease and seronegative for ruminant lentiviruses were inoculated intranasally or intrasinusally with either nasal Huid from goats with naturally occurring EIT or EIT retrovirus concentrated from such Huids. EIT was induced in three kids after 12-24 months. The EIT retrovirus was demonstrated in tumor material from each of the three kids by western blotting and electron microscopy. All kids were seronegative for ruminant lentiviruses. Enzootic intranasal tumors (EIT, enzootic nasal ad- enocarcinoma) of sheep and goats are diseases char- acterized by neoplastic transformation of nasal glands. Profuse seromucous nasal exudate, dyspnea, stertorous breathing, and skull deformations are characteristic of these two disease^.^,^-'%",'^ Although the etiology of these diseases is unknown at present, several features suggest that they are infectious and that a virus could be in- volved. Ultrastructural studies have revealed retrovi- rus-like particles in association with epithelial cells in both sheep and g~ats.*,~,'J~ Furthermore, nasal exudate and tumor tissue from goats with EIT contain a reverse transcriptase activity associated with a particle with typical bouyant density. The same particle contained a 25,000-Mr protein that cross-reated antigenically with the p27 capsid protein of Mason-Pfizer monkey virus (MPMV) and p25 of sheep pulmonary adenomatosis retrovirus. It also contained a low-Mr protein related to p 10- 12 of MPMV.3 A particle-associated 25,000- Mr protein that cross-reacted with the p27 of MPMV also has been detected in nasal fluids of sheep with naturally occurring EIT.3 Thus each of these two nasal tumors of small ruminants is associated with a type- D-like retrovirus. Epidemiologic observations pointing to the infec- tious nature of EIT in sheep have been supported by the successful experimental transmission in sheep us- ing filtrates of tumor that were free of bacteria and ce1ls.l In this paper, we report the successful trans- mission of EIT in goats using nasal exudate containing the type-D-like retrovirus.