Assane M, Sere A
Ecole inter-Etats des sciences et médecine vétérinaires, Département de physiologie, pharmacodynamie, thérapeutique, Dakar, Sénégal.
Ann Rech Vet. 1990;21(4):285-9.
Seasonal and gestational variations of triiodothyronine (T3) and thyroxine (T4) plasma concentrations were evaluated in 12 pregnant and 6 non pregnant adult Sahel Peulh ewes. Blood samples were drawn from all animals at different dates for radio-immunoassay. In this particular breed of sheep, plasma triiodothyronine and thyroxine levels did not present significant variations from the beginning of the cool season (December) until the end of the dry warm season (May). On the contrary, a highly significant rise of hormones (P less than 0.01) was observed at the onset of the humid warm season (June). Moreover, a significant decrease of thyroid hormone plasma levels (P less than or equal to 0.05) greater for thyroxine than triiodothyronine was observed at the end of gestation, particularly in twin pregnancies. At birth, the thyroxine plasma level was higher in single than in twin lambs (139.6 +/- 66.5 vs 110.5 +/- 43.8 ng/ml).
在12只怀孕的和6只未怀孕的成年萨赫勒富拉尼母羊中评估了血浆三碘甲状腺原氨酸（T3）和甲状腺素（T4）浓度的季节性和妊娠期变化。在不同日期从所有动物采集血样进行放射免疫测定。在这种特定品种的绵羊中，从凉爽季节开始（12月）到干燥温暖季节结束（5月），血浆三碘甲状腺原氨酸和甲状腺素水平没有呈现出显著变化。相反，在潮湿温暖季节开始时（6月）观察到激素水平显著升高（P小于0.01）。此外，在妊娠末期观察到甲状腺激素血浆水平显著下降（P小于或等于0.05），甲状腺素的下降幅度大于三碘甲状腺原氨酸，特别是在双胎妊娠中。出生时，单胎羔羊的血浆甲状腺素水平高于双胎羔羊（139.6±66.5对110.5±43.8 ng/ml）。
