Effect of ammonium chloride supplementation on urine pH and urinary fractional excretion of electrolytes in goats.

OBJECTIVE: To determine whether dietary supplementation with ammonium chloride would affect urine pH or urinary fractional excretion (FE) of electrolytes in goats fed grass hay.
DESIGN: Clinical trial. ANIMALS: 15 yearling castrated male goats. PROCEDURES: In the dose response study, 3 yearling goats fed orchard grass hay and water ad libitum were administered ammonium chloride at either 200, 400, or 500 mg/kg (91, 182, or 227 mg/lb), PO, every 24 hours. In the FE study, 8 goats fed orchard grass hay were randomly divided into either a treatment (n=4) or a control group (4). In the treatment group, ammonium chloride was administered at 450 mg/kg (2.25% of dry matter intake [DMI]), PO, every 24 hours for 8 days. The FE of electrolytes was compared between groups; FE measurements were also determined for 4 client-owned goats fed alfalfa hay.
RESULTS: Ammonium chloride administered at 450 mg/kg (2.25% of DMI) achieved and maintained urine pH<6.5 for 24 hours. Goats fed orchard grass hay with ammonium chloride supplementation had significantly higher FE of calcium and chloride than did goats fed orchard grass hay without supplemental ammonium chloride. CONCLUSIONS AND CLINICAL RELEVANCE: Dietary ammonium chloride supplementation at a dose of 450 mg/kg may be necessary to achieve a urine pH<6.5 in goats. Further studies of ammonium chloride supplementation and urolithiasis in goats fed low-calcium diets are indicated.