Two experiments were conducted to study the effects of (Na + K)/Cl ratio on the diet of commercial laying hens, at the end of egg production by the addition of sodium bicarbonate (NaHCO3), sodium chloride (NaCl), potassium chloride (KCl) and ammonium chloride (NH4Cl), with regard to productive parameters and plasma blood characteristics. The first experiment involved five treatments: 0.30% NaCl; 0.30% NaCl + 0.95% NaHCO3; 0.38% KCl + 0.67% NaHCO3; 0.8% KCl + 1.62% NaHCO3 and 0.38% KCl + 2.56% NaHCO3. The (Na + K)/Cl ratios were respectively, 3.46; 4.46; 4.46, 5.46 e 6.46. The second experiment involved four treatments: 0.30% NaCl; 0.47% NaHCO3 + 0.19 NH4Cl; 1.17% NaHCO3 + 0.19% NH4Cl and 1.88% NaHCO3 + 0.19% NH4Cl. The (Na+K)/Cl ratios were 3.46; 4.46; 5.46 and 6.46, respectively. In the first experiment, the greatest feed intake was observed in the hens fed diet with 0.30% NaCl. The birds fed KCl presented better feed conversion. It was observed an increase in the plasma blood phosphorus and plasma blood pH. The birds fed diets with 5.46 of (Na +K)/Cl ratio presented the highest plasma blood phosphorus. The hens receiving the diets with the 4.46 and 6.46 (Na+K)/Cl ratios presented an increase in the plasma blood pH. In the second experiment, the egg weight decreased as NaHCO3 increased in the diet.
blood; laying hens; performance; shell thickness
