Tropical Animal Health and Production
Potassium phosphate and potassium carbonate administration by feed or drinking water improved broiler performance, bone strength, digestive phosphatase activity and phosphorus digestibility under induced heat stress conditions
I. Ansari1 , S. Khalaji1 & M. Hedayati1
1Department of Animal Science, Faculty of Agricultural Sciences, Malayer University, Malayer 65719-95863, Iran
Potassium phosphate (K2HPO4) and potassium carbonate (K2CO3) administration by feed or water were evaluated on broiler performance, bone strength, alkaline phosphatase activity (ALP), and phosphorus digestibility under heat stress and high chloride condition. Experimental groups include control; 15 cc/kg K2HPO4; 30 cc/kg K2HPO4; 15 cc/l K2HPO4; and 3.7 g/kg K2CO3. Body weight (BW), feed and water consumption, plasma potassium, phosphorus, and calcium concentration along with plasma and digestive ALP and intestinal digesta pH were measured during the trial. Tibia ash, calcium and phosphorus content, and breaking strength were measured on days 21 and 42 and phosphorus digestibility on day 36 of age. As a result of this, study feed and water consumption was increased by supplementation of the feed or water with K2HPO4 (P ≤ 0.001). K2HPO4 increased body weight at 42 days of age (P ≤ 0.001). Tibia ash and phosphorus content was increased by K2HPO4 supplementation (P ≤ 0.004; P ≤ 0.003). K2CO3 did increased tibia ash but not changed tibia phosphorus content significantly. Tibia shear force, shear energy, extension, and length were improved by K2HPO4 administration at 42 days of age (P ≤ 0.001). Administration of either feed or water with K2HPO4 increased plasma potassium, phosphorus, and calcium concentration at 21 days of age, whereas K2CO3 reduced plasma potassium at 21 days of age (P ≤ 0.05). Plasma ALP reduced by addition of 15 cc K2HPO4 and K2CO3 to diets at 42 days of age, whereas digestive ALP was increased by inclusion of K2HPO4 and not by K2CO3. Supplementation of either feed or water with K2HPO4 increased phosphorus digestibility, whereas K2CO3 reduced phosphorus digestibility (P ≤ 0.003). Jejunum and ileum pH was reduced by K2HPO4 or by K2CO3 at 21 and 42 days of age (P ≤ 0.006; (P ≤ 0.05). Over all, results of current study revealed that K2HPO4 can be a suitable potassium salt choice instead of KCL in hot weather conditions especially when the water or diet contains high levels of chloride.
Keywords: Potassium phosphate . Potassium carbonate . Heat stress . Chloride