Effect of iodine source and level on milk yield and composition of Friesian cows.
Abstract: Twenty five lactating Friesian cows were used to study the effect of iodine source (potassium iodide, KI and iodinated casein, IC) and level (0.6, and 1.0 mg / kg DMI) on milk production and composition during the different seasons (summer vs. autumn and winter). The effect of iodine supplementation on diet digestibilities, ruminal activity, blood constituents and physiological status of cows were also studied. The experimental ration was consisted of 60% concentrate mixture and 40% rice straw with berseem hay (on DM basis). .
Iodine supplementation decreased all the nutrient digestibilities and the nutritive value of diets except the high level of iodinated casein ration (H-IC) which recorded higher (P<0.05) DCP value. Ration containing low level of potassium iodide (L-KI) had higher DMI, while the daily intakes of TDN, SV and DCP were higher for cows fed low level of iodinated casein ration (L-IC). There were significant increases in 4% Fat-corrected milk yield and economical efficiencies for cows fed iodine supplemented diets. Moreover, iodine supplementation significantly increased milk contents of fat, protein, lactose, ash, energy, iodine concentration, triiodothyronine, thyroxine, serum iodine concentrations, rectal temperature, respiration rate and pulse rate. Total VF A's concentrations before and after feeding were significantly higher with H-KI ration. Blood serum proteins and creatinine values were not affected by iodine supplement, while glucose content was affected by increasing iodine level, From these results, it could be. concluded that iodine supplementation had beneficial effects on the productive performance of lactating cows and tended to decrease feed costs and increase economical efficiency.
Publication year 1998
Availability location مكتبة معهد بحوث الانتاج الحيوانى- شارع نادى الصيد - الدقى - الجيزة
Availability number 596
Organization Name
Country Egypt
Department Animal Nutrition Research Departement
Author(s) from ARC
Agris Categories Animal feeding
AGROVOC
TERMS		 Animal nutrition. Cows. Iodine. Milk. Milk yield.
Publication Type PhD Thesis
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