Two experiments were designed to determine the effects of dietary iodine and teat-dipping on the iodine status of dairy cows and their milk. Eight mid-lactation Holstein dairy cows with an initial body weight of 642 ± 62 kg and 145 ± 21 d in milk were studied for 2 periods over 44 d. In period 1, all cows were fed a basal diet supplemented with potassium iodide (KI) (10 mg I/Kg DM) for 8 d with no teat-dipping. In period 2, a pre-milking teat-dipping was applied for 10 d followed by no teat-dipping before milking (udder wash without iodine) and then post-dipping treatment was applied for 5 d. Feeding KI increased concentrations of iodine in serum, urine, and milk (P < 0.05). Switching from the KI supplementation to no iodine addition resulted in an immediate decrease of iodine in serum, urine, and milk (P < 0.05). Post teat-dipping resulted in increased iodine levels in serum, urine, and milk (P < 0.05). However, pre-milking teat-dipping did not affect iodine concentration compared to post-dipping. A 250 mL cup of milk from the control and KI-supplemented diets would provide 29.4% and 68.4%, respectively, of the adult-recommended dietary allowance for iodine. In conclusion, milk iodine concentration could be effectively enhanced by KI supplementation and teat-dipping practices.

设计了两个实验来确定膳食碘和乳头浸渍对奶牛及其牛奶碘状态的影响。8 头泌乳中期的荷斯坦奶牛初始体重为 642 ± 62 kg，在牛奶中 145 ± 21 天，在 44 天的两个时期内进行了研究。在第 1 阶段，所有奶牛都饲喂添加碘化钾 (KI)（10 mg I/Kg DM）的基础日粮，持续 8 天，不进行乳头浸渍。在第2阶段，进行挤奶前浸乳10天，然后在挤奶前不浸乳（无碘洗乳房），然后进行后浸处理5天。喂食 KI 会增加血清、尿液和牛奶中的碘浓度（P < 0.05）。从 KI 补充剂转换为不添加碘会导致血清、尿液和牛奶中的碘立即减少。P < 0.05)。乳头后浸渍导致血清、尿液和牛奶中的碘水平增加（P < 0.05）。然而，与后浸渍相比，挤奶前的乳头浸渍不会影响碘浓度。一杯 250 毫升来自对照饮食和 KI 补充饮食的牛奶将分别提供成人推荐饮食中碘的 29.4% 和 68.4%。总之，补充 KI 和乳头浸渍方法可以有效提高乳碘浓度。