Factors associated with success rate of oral force-feeding ammonium chloride administration to acidify urine in goats.

Background: Ammonium chloride is the most common urine acidifier used for urolithiasis treatment and prevention in goats.

Aim: The objective of this study was to determine a guideline for ammonium chloride administration to acidify urine in goats.

Methods: A three-period, three-treatment crossover study was conducted in three groups, with 10 female goats in each group. Three dosages of ammonium chloride were used (250, 350, or 450 mg/kg). In each experimental period, ammonium chloride was orally administered for three consecutive days or until the urine pH dropped below 6.5. Urine samples were collected to measure the pH before each administration and 1 day after the last administration. The Cox proportional hazards model was conducted to identify factors associated with the success rate in reducing the urine pH below 6.5 at a time.

Results: The dosage of ammonium chloride and period of administration were significantly associated with the success rate (p < 0.001). The success rates during a unit of time for goats receiving 350 mg/kg and 450 mg/kg were greater than that of goats receiving 250 mg/kg. The second and third periods of ammonium chloride administration provided higher success rates during a unit of time compared to the first period. The success rate was also associated with the pretreatment urine pH (p = 0.044). There was a higher success rate for goats with a lower pretreatment urine pH.

Conclusion: The recommended ammonium chloride dosage was 350 mg/kg. Periodic use can be considered to achieve better outcomes. The pretreatment urine pH should be measured to anticipate the clinical response.