اثرات توازن الكتروليت هاي جيره بر عملكرد و كيفيت پوسته ي تخم مرغ مرغ هاي تخم گذار در شرايط تنش گرمايي و حرارتي خنثي در مرحله ي اول تخم گذاري

The effects of dietary electrolyte balance on performance and eggshell quality of laying hens exposed to heat stress and thermo neutral condition in early laying period

This study was conducted to evaluate the effects of different dietary electrolyte balance on performance and egg quality in early period of egg production under heat stress and thermo neutral condition. This experiment was done on hens that were in early of egg production period. Number of 256 Hy- line W-36 laying hens from 24 to 34 weeks of age were placed in two separated experimental room under heat stress and thermo neutral condition. Each experiment was earned out in a completely randomized design. Diets were formulated with inclusions of NaCl, NaHC03, KHC03 and NH4C1 to give different dietary electrolyte balances (DEB) as 0, 120, 240 and 360 mEq/kg and were fed to laying hens for 10 weeks. Results of these experiments showed that performance of laying hens were not significantly affected by diets of various DEB in both heat stress and thermo neutral conditions. Eggshell quality were significantly affected by DEB (p<0.Q5). Under heat stress, eggshell weight and egg weight/surfaces and under thermo neutral condition, egg specific gravity, eggshell weight, eggshell thickness, eggshell ash and egg weight/surfaces were significantly affected by DEB and improved by increasing dietary electrolyte balance from 120 to 360 mEq/kg in many cases. In conclusion, increasing DEB to 360 mEq/kg in early period of egg production in heat stress and thermo neutral condition can improve eggshell quality.