BALANÇO ELETROLÍTICO P ARA SUÍNOS MACHOS CASTRADOS EM CRESCIMENT O MANTIDOS EM AMBIENTE DE ALTA TEMPERA TURA Electrolyte balance of growing males castrated swines in a high temperature environment

The effect of electrolyte balance (EB) in diets with different levels of electrolytes for growing swine under high environmental temperature was evaluated. Two hundred castrated pigs with initial weight of 25.3±1.3 kg and final weight of 68.8±3.4 kg were allotted in a completely randomized experimental design with five treatments and four replicates with 10 pigs per experimental unit, for the growing phase T1 (control) diet without electrolyte 191 mEq/kg; T2 (NaHCO 3 ) diet supplemented with sodium bicarbonate (NaHCO 3 ) 250 mEq/kg; T3 (NaHCO 3 +KCl) diet supplemented with (NaHCO 3 ) and potassium chloride (KCl) 250 mEq/kg; T4 (NaHCO 3 ) diet supplemented with (NaHCO 3 ) 300 mEq/kg; T5 (NaHCO 3 +KCl) diet supplemented with NaHCO 3 and (KCl) 300 mEq/kg. The performance parameters evaluated were: feed intake, daily gain, nitrogen intake, lysine intake, efficiency of nitrogen use for weight gain, efficiency of lysine use for weight gain and the gainto-feed ratio and the physiological parameters, respiratory frequency and rectal temperature. Blood was colleted to measure serum concentration of Na, Cl and K. The average temperature was 29.65±3.80o C with relative humidity of 69.6±10.4%, Black Globe Temperature of 31.95±1.98o C and temperature index calculated of 80.51±2.44. The levels of EB decreased (P 0.05). The correction of EB did not influence the growth of the swine.