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

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.

PMID 31444665  /  I Ansari, S Khalaji, M Hedayati