title: Effect of dietary iodine on thyroid hormones and energy blood metabolites in lactating goats.
abstract: Aim of this work was to evaluate if long-term dietary supplementation of potassium iodide (KI) to dairy goats can influence metabolic and hormonal parameters. Thirty Sarda crossbred dairy goats were divided into three groups, which were orally administered 0 (control group; CON), 0.45 (low iodine group; LI) or 0.90 (high iodine group; HI) mg of KI/day, respectively. The daily dose of KI (76.5% of iodine) was administered as salt dissolved in water for 8 weeks. Plasma contents of nonesterified fatty acids (NEFA), urea, glucose, insulin, free triiodothyronine (FT(3)) and thyroxine (FT(4)) were determined weekly. Iodine supplementation increased significantly the FT(3) hormone (P = 0.007) and FT(3)/FT(4) ratio (P = 0.001) and tended to influence the FT(4) hormone (P = 0.059). An iodine level × week of sampling interaction for NEFA (P = 0.013) evidenced a temporary concentration increase in supplemented groups. The 'Revised Quantitative Insulin Sensitivity Check Index' increased with KI supplementation (P ≤ 0.01). Blood urea nitrogen (BUN) and insulin were lowered (P ≤ 0.01) by iodine supplementation (groups LI and HI; P ≤ 0.01). The glucose concentration evidenced an iodine level × week of sampling interaction (P = 0.025) due to an unexpected and temporary increase of its concentration in the CON group. Glucose concentration was decreased by KI supplementation only in LI group (P < 0.05). In conclusion, the daily supplementation of low doses of KI can improve insulin sensitivity and decrease BUN in dairy goats.
authors.affiliation: Dipartimento di Agraria, Università di Sassari, Italy. anudda@uniss.it
authors.forename: A
authors.initials: A
authors.lastname: Nudda
authors.forename: G
authors.initials: G
authors.lastname: Battacone
authors.forename: G
authors.initials: G
authors.lastname: Bomboi
authors.forename: B
authors.initials: B
authors.lastname: Floris
authors.forename: M
authors.initials: M
authors.lastname: Decandia
authors.forename: G
authors.initials: G
authors.lastname: Pulina
mesh_terms: D000818:Animals; D001774:Blood Chemical Analysis / Q000662:veterinary; D019587:Dietary Supplements / Q000032:analysis*; D004305:Dose-Response Relationship, Drug; D004734:Energy Metabolism; D005260:Female; D006041:Goats / Q000097:blood / Q000378:metabolism*; D011193:Potassium Iodide / Q000008:administration & dosage*; D013974:Thyroxine / Q000097:blood*; D014284:Triiodothyronine / Q000097:blood*
chemical_list: D014284:Triiodothyronine; D011193:Potassium Iodide; D013974:Thyroxine