Boosinger T R, Brendemuehl J P, Bransby D L, Wright J C, Kemppainen R J, Kee D D
Department of Pathobiology, College of Veterinary Medicine, Auburn University, AL 36849-5519.
Am J Vet Res. 1995 Jan;56(1):66-9.
Newborn foals of mares grazing on Acremonium coenophialum-infected fescue pasture throughout gestation or from gestation day 300 to parturition had increased gestation duration and decreased serum triiodothyronine concentration. Pregnant mares were allotted to 4 treatments: grazing continuously on endophyte-free (E-) fescue, grazing continuously on endophyte-infected (E+) fescue, grazing on E+ fescue from gestation day 300 to parturition, and grazing on E+ fescue from conception to gestation day 300. Morphometric studies indicated that foals born to mares exposed to endophyte late in gestation had large, distended thyroid follicles lined by flat cuboidal epithelial cells. Mean triiodothyronine concentration in foals exposed to endophyte (395.2 ng/dl) was decreased (P < 0.01), compared with mean values in control foals (778.0 ng/dl). Thyroxine and reverse triiodothyronine concentrations were not significantly different among groups. Foal organ weight as a percentage of foal body weight was not significantly different among experimental groups.
在整个妊娠期或从妊娠第300天到分娩期间，在感染了内生真菌（Acremonium coenophialum）的羊茅草地上放牧的母马所生的新生马驹，妊娠期延长，血清三碘甲状腺原氨酸浓度降低。将怀孕母马分配到4种处理组：持续在无内生真菌（E-）的羊茅草地上放牧、持续在感染内生真菌（E+）的羊茅草地上放牧、从妊娠第300天到分娩期间在E+羊茅草地上放牧、从受孕到妊娠第300天在E+羊茅草地上放牧。形态学研究表明，在妊娠后期接触内生真菌的母马所生的马驹，其甲状腺滤泡大且扩张，内衬扁平立方上皮细胞。与对照马驹的平均值（778.0 ng/dl）相比，接触内生真菌的马驹的平均三碘甲状腺原氨酸浓度（395.2 ng/dl）降低（P < 0.01）。各实验组之间甲状腺素和反三碘甲状腺原氨酸浓度无显著差异。各实验组马驹器官重量占马驹体重的百分比无显著差异。
