Blood thyroid hormone and circulating lipid profiles in multiparous Holstein dairy cows

摘要

Chalmeh A, Hajimohammadi A, Nazifi S., Blood thyroid hormone and circulating lipid profiles in multiparous Holstein dairy cows, Onl J Vet Res., 19(10): 672-678, 2015. Multiparous Holstein cows in early, mid and late lactations, far-off and close-up dry periods were sampled for blood triiodothyronine (T3), thyroxine (T4), free T3 (FT3), free T4 (FT4), cholesterol, triglyceride (TG), high, low and very low density lipoproteins (HDL, LDL and VLDL). Compared (P<0.05) with other groups, cholesterol in midand late lactation cows was higher. LDL in mid lactation cows was highest and lowest in far-off dry cows. Glucose, TG, HDL and VLDL values did not differ between groups. In early lactation cows T3 was higher. In early and mid-lactation cows T4 was lower. Cows in early lactation had highest FT3 whereas those with close-up dry periods lowest FT3. In far-off dry cows FT4 was higher. There were no correlations between any lipid value except for TG with VLDL. T3 correlated with T4 in all cows but not with FT3 or FT4. FT3 correlated with FT4 in all groups. Cholesterol correlated with TG and T3 and T4 in all cows.