Effect of added zinc and phytase on growth and feeding economy in crossbred (Hampshire × Assam local) pigs

Twenty four weaned crossbred (Hampshire × Assam local) piglets (avg.11.0kg body weight) were allotted to four dietary treatments, in a 2×2 factorial arranged in RBD and offered ad libitum diets. The zinc contents in the grower and finisher diets were 50.9 and 50.2 ppm respectively. No zinc was added in the diet of T₁ group which in T₂ group phytase was added additionally at level of 200unit/kg diet. Zinc was supplemented in the diet of T₃ group as ZnSO₄.7H₂O to make it 100ppm. In the diet of T₄ group zinc was supplemented to make it 100ppm along with supplementation of phytase at level of 200unit/kg diet. The feed efficiency was found to be significantly lowest in T₁ group and highest in T₄ group comparing that of pigs of the other treatment group T₂ and T₃ due to phytase level. The lowest cost for per kg live weight gain was recorded in T₄ (54.97) followed by T₃ (58.53), T₂ (57.48) and T₁ (59.97), however the difference between these were non-significant. The lowest cost per kg live weight gain was recorded in T₄ followed by T₂, T₃ and T₁, respectively. 100ppm zinc supplementation with 200 phytase unit per kg diet to the pigs gave best economical returns.