Possibility of Neospora caninum infection by venereal transmission in CB-17 scid mice.
CB-17 scid and BALB/c male mice were inoculated intraperitoneally with Neospora caninum to examine the possibility of its venereal transmission. Some of these mice were killed on days 7 and 20 post-inoculation to examine the genital organs for presence of the parasite. The remaining scid male mice were housed with non-infected female mice from day 7 p.i. and kept with them for 14 days. These scid mice died between days 28 and 35 p.i. N. caninum DNA was detected in the testis of mice on days 7 and 20 p.i. by PCR and tachyzoite viability was determined by bioassay conducted by means of mouse inoculation. Microscopically, fewer tachyzoites were detected in the testis obtained on day 20 p.i., than in other organs. The inoculated BALB/c male mice survived until the end of the experiment with no clinical signs and N. caninum DNA was detected in the testis on day 7 p.i. but not on day 14 p.i. Five of eight female scid mice housed with infected males became pregnant. Tachyzoites were detected in three of these mice and their neonates (n=3, 5 and 13, respectively). In three non-pregnant mice, no parasite was detected. Two of the four female BALB/c mice housed with infected male scid mice became pregnant but the parasite was not detected in them or in the neonates (n=3 and 13, respectively). These results indicate that the tachyzoites were present in the genital organs of the immunodeficient mice from day 7 p.i. and suggest that transmission may occur through mating with male mice.
Masuda
Tsuneyuki
T
Department of Basic Veterinary Science, School of Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro 080-8555, Japan.
Kobayashi
Yoshiyasu
Y
Maeda
Ryuichiro
R
Omata
Yoshitaka
Y
D000818:Animals; D000831:Animals, Newborn / Q000469:parasitology; D003048:Coccidiosis / Q000635:transmission / Q000662:veterinary*; D016054:DNA, Protozoan / Q000032:analysis; D005260:Female; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D016513:Mice, SCID; D018688:Neospora / Q000302:isolation & purification*; D011247:Pregnancy; D011467:Prostate / Q000469:parasitology; D012669:Seminal Vesicles / Q000469:parasitology; D012749:Sexually Transmitted Diseases / Q000469:parasitology* / Q000635:transmission*; D013997:Time Factors
D016054:DNA, Protozoan