Department of Animal Science, Faculty of Agriculture, Urmia University, Urmia, Iran.
J Anim Physiol Anim Nutr (Berl). 2020 May;104(3):876-885. doi: 10.1111/jpn.13321. Epub 2020 Feb 10.
This study was conducted to determine the effects of dietary inclusion levels of iodine supplementation and duration of feeding on performance, carcass characteristics, meat iodine, thyroid hormones and some indices including red blood cell, haematocrit, haemoglobin, aspartate transaminase, alanine transaminase and alkaline phosphatase in broilers. A total of 450 one-day-old male broiler chicks were used during a 42 days experiment in 9 treatments with five replicates pen for each treatment. The experimental design was a 3 × 3 factorial arrangement of treatments including three levels of iodine (0, 2.5 and 5 mg/kg as a source of potassium iodide) during the T (total, 1-42 days), GF (grower and finisher, 11-42 days) and F (finisher, 25-42 days) periods (p < .05). The results demonstrated that none of the performance data (feed intake, body weight gain and feed conversion ratio) were influenced by level and duration of iodine consumption (p > .05). The diet supplemented with 5 mg/kg iodine had no effects on relative weights during total (T) and grower and finisher (GF) periods, but there was an effect on the finisher (F) period. Moreover, increasing the iodine level from 0 to 5 mg/kg linearly decreased the relative weights of the both small intestine and jejunum (p < .05). Increasing the iodine level from 0 to 5 mg/kg linearly increased the breast iodine content. Also, the highest breast meat enrichment was observed during the T period (p < .05). Blood triiodothyronine concentration was not changed by any of the iodine level and duration of consumption, but tetraiodothyronine concentration was higher for T period than GF and F ones (p < .05) and even linearly increased by increasing the level of dietary iodine for 0 to 5 mg/kg (p < .05). It was concluded that 5 mg/kg iodine from day 1 to day 42 of age is needed in the diet to enrich the broiler meat.
本研究旨在确定日粮中添加碘补充剂的水平和喂养时间对肉鸡生产性能、胴体特性、肌肉碘含量、甲状腺激素以及红细胞、红细胞压积、血红蛋白、天门冬氨酸转氨酶、丙氨酸转氨酶和碱性磷酸酶等一些指标的影响。在一项为期 42 天的试验中，使用了 450 只 1 日龄雄性肉鸡，每个处理有 5 个重复栏。试验设计为 3 个因素 3 水平的析因设计，包括日粮碘水平（0、2.5 和 5mg/kg 碘化钾）、生长期（1-42 天）、育肥期（11-42 天）和育肥后期（25-42 天）（p<.05）。结果表明，碘的摄入量和持续时间对生产性能数据（采食量、体重增重和饲料转化率）没有影响（p>.05）。日粮添加 5mg/kg 碘对生长期（T）和育肥期（GF）的相对体重没有影响，但对育肥后期（F）有影响。此外，从 0 到 5mg/kg 线性增加碘水平会降低小肠和空肠的相对重量（p<.05）。从 0 到 5mg/kg 线性增加碘水平会增加胸肌碘含量。此外，T 期观察到胸肉的富集度最高（p<.05）。碘的摄入量和持续时间对血液三碘甲状腺原氨酸浓度没有影响，但四碘甲状腺原氨酸浓度在 T 期高于 GF 和 F 期（p<.05），甚至随着日粮碘水平从 0 到 5mg/kg 的增加而线性增加（p<.05）。结论是，在日粮中从 1 日龄到 42 日龄需要添加 5mg/kg 碘来富集肉鸡肉。
