Controlling ammonia concentrations in calf hutches with sodium bisulfate.

Neonatal calves are susceptible to respiratory irritation and lung damage via elevated ammonia concentrations in calf facilities. The study objective evaluated the addition of Sodium Bisulfate (SBS; SurpHace; Jones-Hamilton) to reduce ammonia concentrations in calf hutches. Ninety Holstein male calves were blocked by body weight (BW) and randomly assigned to 1 of 2 treatments starting on June 4, 2025. Treatments were 1): Control: no SBS applied to calf hutch wheat straw bedding and 2): 454 g of SBS applied twice per week on Tuesday and Saturday mornings after feeding. SBS was applied with a Scotts WIZZ grass seeder to achieve even distribution of SBS in the hutches. Fresh chopped straw was added again on July 7 and ground soyhulls were added on July 14 and July 21 with the experiment ending on July 30. Ammonia readings were collected weekly starting wk 3 on Thursday mornings following feeding using a single personal NH3 gas detector (Model FD-80A (Forensics Detectors, Rolling Hills Estates, CA). The use of SBS reduced (P < 0.01) ammonia concentrations by approximately 85% (10.5 and 1.63 mg/kg for Control and SBS, respectively). There was a treatment by week interaction with the greatest reductions occurring during wk 7 and 8. Calves with SBS added to their bedding had increased (P < 0.02) BW gain (30.3 and 33.9 kg) and average daily gains (ADG; 541 and 605 g/d) approximately 12%. There was a tendency for increased calf starter consumption (0.63 and 0.73 kg/d) and a tendency for a treatment by week interaction demonstrating increased calf starter intake during wk 6, 7, and 8 for calf hutches receiving SBS compared with Control hutches. Feed conversions (0.495 and 0.511 kg/kg) were similar among both hutch treatments. Heart girth gain (12.5 and 14.5 cm) was improved for calves housed in hutches receiving SBS compared with Control hutches while remaining frame measurements were similar among calves housed in hutches without or with SBS. Scour scores were similar among calves housed in both hutch treatments. SBS was effective in reducing calf hutch ammonia concentrations by 85%, which supported improved BW gains, ADG, calf starter intake, and heart girth gains.