Aumont G, Lamand M, Tressol J C
Laboratoire des Maladies Nutritionnelles, INRA, Theix, Ceyrat, France.
Reprod Nutr Dev (1980). 1989;29(1):113-25. doi: 10.1051/rnd:19890110.
In a first experiment, 2 groups of 46 and 47 multiparous ewes received diets which provided an iodine intake of 0.36 and 0.26 mg/kg dry matter (group C) and, 2.01 and 1.94 mg/kg (group D), respectively, for pregnancy and lactation. In a second experiment, 3 groups of 10 nulliparous ewes received diets which provided an I intake of 0.13 and 0.12 mg/kg dry matter (group A), 0.22 and 0.20 mg/kg dry matter (group B), and 10.77 and 8.88 mg/kg dry matter (group E), respectively, for pregnancy and lactation. Observations and sampling were carried out on the ewes from the first third of pregnancy to the 2nd and the 6th week of lactation. The diets provided adequate nutrition for pregnant and lactating ewes. Dietary I content had no effect on the dry matter intake, the size or the weight of the litter and the length of pregnancy. Plasma inorganic iodine (PII) was less affected by the I intake during lactation than during pregnancy. The excretion of I in milk induced a decrease in PII between pregnancy and lactation. The I in urine expressed as microgram I/g creatinine was largely affected by the intake. Colostrum I was 6.7, 4.0, 1.2, 1.3 and 1.5 times higher in groups A, B, C, D and E than the I in milk collected 1 week postpartum. Milk iodine (MI) content and the ratio MI/PII were markedly dependent on the I intake. During pregnancy, plasma T4 concentration decreased for each group. Plasma T4 concentration remained low during lactation in the low I intake group, whereas it increased at the same time in the other groups. The plasma T3 concentration decreased at the 6th week of lactation in the highest I intake group. Experimental values showed that 0.12 mg I/kg dry matter induced depletion in the I stocks of pregnant and lactating ewes, whereas an I intake above 10 mg I/mg dry matter disturbed the metabolism of thyroid hormones.
在第一个实验中，两组分别有46只和47只经产母羊，在怀孕和泌乳期分别给予碘摄入量为0.36毫克/千克干物质和0.26毫克/千克干物质的日粮（C组），以及2.01毫克/千克和1.94毫克/千克的日粮（D组）。在第二个实验中，三组分别有10只初产母羊，在怀孕和泌乳期分别给予碘摄入量为0.13毫克/千克干物质和0.12毫克/千克干物质的日粮（A组）、0.22毫克/千克和0.20毫克/千克干物质的日粮（B组），以及10.77毫克/千克和8.88毫克/千克干物质的日粮（E组）。对母羊从怀孕前三分之一期至泌乳第2周和第6周进行观察和采样。日粮为怀孕和泌乳母羊提供了充足的营养。日粮碘含量对干物质摄入量、产仔大小或重量以及怀孕时长均无影响。与怀孕期相比，泌乳期碘摄入量对血浆无机碘（PII）的影响较小。乳汁中碘的排泄导致怀孕期和泌乳期之间PII降低。以微克碘/克肌酐表示的尿碘受摄入量影响很大。初乳碘含量在A、B、C、D和E组中分别比产后1周采集的乳汁碘含量高6.7倍、4.0倍、1.2倍、1.3倍和1.5倍。乳碘（MI）含量和MI/PII比值明显取决于碘摄入量。在怀孕期间，每组的血浆T4浓度均下降。低碘摄入量组在泌乳期血浆T4浓度仍保持较低水平，而其他组在此期间则同时升高。在最高碘摄入量组中，泌乳第6周时血浆T3浓度下降。实验值表明，0.12毫克碘/千克干物质会导致怀孕和泌乳母羊碘储备耗竭，而碘摄入量高于10毫克碘/毫克干物质会扰乱甲状腺激素的代谢。
