Abstract
The relationship between stage of reproductive tract maturity and susceptibility to the experimental establishment of persistent infection with equine arteritis virus, (EAV) was investigated in 21 prepubertal and 15 peripubertal colts. Five of six prepubertal colts inoculated intranasally remained infected in the reproductive tract from post-challenge day 28 to 93 and two of six from post-challenge day 120 to 180. No virus was detected in five of these animals killed on post-challenge day 210. Each of two peripubertal colts remained infected in the reproductive tract at post-challenge day 60 and one of nine was found to be persistently infected with EAV 15 months after challenge. These findings confirm that the virus can replicate in the reproductive tract of a significant proportion of colts for a variable period of time after clinical recovery in the absence of circulating concentrations of testosterone equivalent to those found in sexually mature stallions. Long-term persistent infection with EAV does not appear to occur in colts exposed to the virus before the onset of peripubertal development. We suggest that colts should be vaccinated at approximately 6 months of age, before peripubertal development but after the disappearance of maternally acquired antibodies.
References
- Carlsten H., Holmdahl R., Tarkowski A., Nilsson L.A. Oestradiol-and testosterone-mediated effects on the immune system in normal and autoimmune mice are genetically linked and inherited as dominant traits. Immunology. 1989;68:209–214. [PMC free article] [PubMed] [Google Scholar]
- den Boon I.A., Snijder E.I., Chirnside E.D., de Vries A.A.F., Horzinek M.C., Spaan W.I.M. Equine arteritis virus is not a togavirus but belongs to the coronavirus "superfamily". Journal of Virology. 1991;65:2910–2920. doi: 10.1128/jvi.65.6.2910-2920.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Doll E.R., Bryans J.T., McCollum W.H., Crowe M.E.W. Isolation of a filterable agent causing arteritis of horses and abortion by mares. Its differentiation from equine abortion, (influenza) virus. Cornell Veterinarian. 1957;47:3–41. [PubMed] [Google Scholar]
- Doll E.R., Knappenberger J.T., Bryans An outbreak of abortion caused by equine arteritis virus. Cornell Veterinarian. 1957;47:69–75. [PubMed] [Google Scholar]
- Fujinami R.S., Oldstone M.B.A. Antibody initiates virus persistence: immune modulation and measles virus infection. In: Notkins A.L., Olstone M.B.A., editors. Concerts in Viral Pathogenesis. Springer; New York: 1984. pp. 187–193. [Google Scholar]
- Fukunaga Y., Imagawa H., Tabuchi E., Akiyama Y. Clinical and virological findings on experimental equine viral arteritis in horses. Bulletin of the Equine Research Institute. 1981;18:110–118. [Google Scholar]
- Inada T., Mims C.A. Live lactic. dehydrogenase virus, (LDV) induces suppressor T cells that inhibit the development of delayed hypersensitivity to LDV. Journal of General Virology. 1986;67:2103–2112. doi: 10.1099/0022-1317-67-10-2103. [DOI] [PubMed] [Google Scholar]
- Little T.V., Holyoak G.R., Timoney P.J., McCollum W.H. Proceedings of the 6th International Conference of Equine Infectious Diseases, Cambridge, 1991. 1992. Output of equine arteritis virus from persistently infected carrier stallions is testosterone dependent; pp. 225–229. [Google Scholar]
- McCollum W.H. Proceedings of the 2nd International Conference of Equine Infectious Diseases, Paris 1969. Karger; Basel and New York: 1970. Vaccination for equine viral arteritis; pp. 143–151. [Google Scholar]
- McCollum W.H., Prickett M.E., Bryans J.T. Temporal distribution of equine arteritis virus in respiratory mucosa, tissues and body fluids of horses infected by inhalation. Research in Veterinary Science. 1971;12:459–464. [PubMed] [Google Scholar]
- McCollum W.H., Timoney P.J. Proceedings of the Grayson Foundation International Conference of Thoroughbred Breeders Organization on Equine Viral Arteritis. Grayson Foundation Inc.; Lexington, KY: 1985. The pathogenic qualities of the 1984 strain of equine arteritis virus; pp. 34–37. [Google Scholar]
- Mims C.A. The pathogenetic basis of viral tropism. American Journal of Pathology. 1989;135:447–455. [PMC free article] [PubMed] [Google Scholar]
- Murphy T.W., Timoney P.J., McCollum W.H. Analysis of genetic variation among strains of equine arteritis virus. In: Powell D.G., editor. Proceedings of the 5th International Conference of Equine Infectious Diseases, Lexington, 1987. University Press; KY, Lexington: 1992. pp. 1–11. [Google Scholar]
- Murphy T.W., Timoney P.J., McCollum W.H. Variation in genomic RNA of equine arteritis virus during long term persistence in the stallion. Veterinary Microbiology. 1993 [Google Scholar]
- Naden J., R.P. Amann, Squires E.L. Testicular growth, hormone concentrations, seminal characteristics and sexual behavior in stallions. Journal of Reproduction and Fertility. 1990;88:167–176. doi: 10.1530/jrf.0.0880167. [DOI] [PubMed] [Google Scholar]
- Neu S.M. Ph.D. Thesis. University of Kentucky; 1988. A study of the pathogenesis and pathologic effects of persistent infection with equine arteritis virus in experimentally infected stallions; pp. 150–200. [Google Scholar]
- Neu S.M., Timoney P.J., McCollum W.H. Proceedings of the 5th International Conference of Equine Infectious Diseases, Lexington. 1988. Persistent infection of the reproductive tract in stallions experimentally infected with equine arteritis virus; pp. 149–154. [Google Scholar]
- Oldstone M.B.A. Scientific American, August. 1989. Viral alteration of cell function; pp. 42–48. [DOI] [PubMed] [Google Scholar]
- Oldstone M.B.A. Viral persistence. Cell. 1989;56:517–520. doi: 10.1016/0092-8674(89)90573-4. [DOI] [PubMed] [Google Scholar]
- Pringle C.R. Current topics. American Society of Microbiology News. 1992;58:475. [Google Scholar]
- Schuurs A.H.W.M., Verheul H.A.M. Effects of gender and sex steroids on the immune response. Journal of Steroids and Biochemistry. 1990;35:157–172. doi: 10.1016/0022-4731(90)90270-3. [DOI] [PubMed] [Google Scholar]
- Senne D.A., Pearson J.E., Carbrey E.A. Proceedings of the United States Animal Health Association Meetings, Louisville, KY. 1985. Equine viral arteritis: a standard procedure for the virus neutralization test and comparison of results of a proficiency test performed at five laboratories; pp. 29–33. [Google Scholar]
- Snijder E.J., den Boone J.A., Bredenbeek P.J., Horzinek M.C., Rijnbrand R., Spaan W.J.M. The carboxyl-terminal part of the putative Berne virus polymerase is expressed by ribosomal frameshifting and contains sequence motifs which indicate that toro- and coronaviruses are evolutionary related. Nucleic Acids Research. 1990;18:435–454. doi: 10.1093/nar/18.15.4535. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Timoney P.J. Proceedings of the Grayson Foundation International Conference of Thoroughbred Breeders Organization on Equine Viral Arterilis. Grayson Foundation Inc.; Lexington, KY: 1985. Clinical, virological and epidemiological features of the 1984 outbreak of equine viral arteritis in the Thoroughbred population in Kentucky, USA. pp. 24–33. [Google Scholar]
- Timoney P.J., McCollum W.H. Proceedings of the 36th Annual Conference of the American Association of Equine Practitioners, Lexington, 1990. 1991. Equine arteritis virus: current clinical and economic significance; pp. 403–409. [Google Scholar]
- Timoney P.J., McCollum W.H., Murphy T.W. Proceedings of the 6th International Conference of Equine Infectious Diseases, Cambridge, 1991. 1992. A longitudinal study of equine arteritis virus infection in Standardbred stallions with special reference to occurrence of the carrier state; pp. 231–237. [Google Scholar]
- Timoney P.J., McCollum W.H., Murphy T.W., Roberts A.W., Willard J.G., Carswell G.D. The carrier state in equine arteritis virus infection in the stallion with specific emphasis on the venereal mode of virus transmission. Journal of Reproduction and Fertility, Supplement. 1987;35:95–102. [PubMed] [Google Scholar]
- Timoney P.J., McCollum W.H., Roberts A.W. Proceedings for the 32nd Annual Meeting of the American Association of Equine Practitioners, Nashville. 1986. Detection of the carrier state in stallions persistently infected with equine arteritis virus; pp. 57–65. [Google Scholar]
- Timoney P.J., McCollum W.H., Roberts A.W., Murphy T.W. Demonstration of the carrier state in naturally acquired equine arteritis virus infection in the stallion. Research in Veterinmy Science. 1986;41:279–280. [PubMed] [Google Scholar]
- Vendramini A.C.L.M., Soo C., Sullivan D.A. Testosterone-induced suppression of autoimmune disease in lacrimal tissue of a mouse model, (NZB/NZW F1) of Sjögren's syndrome. Investigations in Ophthamology and Vision Science. 1991;32:3002–3006. [PubMed] [Google Scholar]
- Westaway E.G., Brinton M.A., Gaidamovich S.Y., Horzinek M.C., Iqarashi L, Kaariainen D.K., Lvov D.K., Porterfield J.S., Russel P.K., Trent D.W. Togaviridae. Intervirology. 1985;24:125–139. doi: 10.1159/000149632. [DOI] [PubMed] [Google Scholar]
