Effects of dietary crude protein and electrolyte balance on production parameters and blood biochemicals of laying hens under tropical summer condition

The objective of this study was to determine the effects of different levels of crude protein (CP) and dietary electrolyte balance (DEB) on productive performance, egg quality, and blood biochemical parameters of laying hens reared during hot summer months. The average minimum and maximum room temperatures recorded from 32 to 42 weeks of age were 27.2 and 36.5 °C, respectively, with relative humidity ranging from 48 to 56 %. A total of 144 Lohmann LSL-Lite laying hens were assigned to each of four dietary treatments with six replicate cages of six birds. The treatments were as follows: CP 15.4 % + DEB 165 mEq/kg (group 1), CP 15.4 % + DEB 250 mEq/kg (group 2), CP 13.9 % + DEB 165 mEq/kg (group 3), and CP 13.9 % + DEB 250 mEq/kg (group 4). In groups 3 and 4, feed conversion ratio and blood uric acid were decreased (P?P?+, and HCO₃ ^? values were also higher (P?