Experimental transmission of a sarcosporidian from Alpine ibex to domestic sheep and goats.

Sporocysts of Sarcocystis sp. from dogs fed with ibex meat were orally inoculated into kids and lambs. Three kids, given 4 x 10(6) and 4 x 10(4) sporocysts, respectively, died from acute sarcocystosis. Schizonts, though found in all the tissues of these kids, were particularly numerous in the kidneys, brain and spinal cord. Another three kids inoculated with 5 x 10(3) sporocysts and two lambs, inoculated with 1 x 10(6) and 5 x 10(3) sporocysts, respectively, showed no clinical signs and were sacrificed between 111 and 130 days after infection. Mature sarcocysts were found both in the heart and striated muscles of these animals. No parasitic stage was found in two kids and two lambs used as uninoculated controls. Biological differences between Sarcocystis sp. from ibex and the other sarcosporidians with a canine-caprine or canine-ovine cycle are stressed.