In addition to solubility and stability, palatability also largely determines the efficacy of a veterinary product for use in drinking water. Good acceptance of medicated water is crucial for correct dosing. Moreover, diseased animals need to keep drinking for complete and fast recovery. The impact of two types of sulfonamide / trimethoprim-based products on water intake was investigated in a field trial.
Table 1. Different sulfonamide / trimethoprim-based products
Nursery pigs (with an average body weight of 16.5 kg) in excellent health, reared under the same conditions and in the same compartments were evenly divided into two mixed sex groups:
Products (Table 1) were administered at the registered dose for five consecutive days at the dose rate as shown in Table 2.
Table 2. Daily dose rate of products
Medicated water was administered via a highly concentrated stock solution using a proportioner set at 1% dilution (1:100). Concentrations of the sulfonamide and trimethoprim in the stock solutions as well as the volumes at the start of administration were equal. Water consumption was measured digitally.
Water intake on the first day of treatment
Cumulative water intake per pig was measured at seven timepoints during the first day of treatment in both groups and the mean water consumption was compared (Figures 1 and 2).
Figure 1. Cumulative water intake at seven different timepoints on day 1 of treatment
Figure 2. Water intake in the sulfamethoxazole / trimethoprim group compared to the HydroTrim® group at seven different timepoints on day 1 of treatment, expressed as a percentage
Daily water intake
Mean daily water consumption per pig was measured from 2 days before to 2 days after the treatment period.
Figure 3. Daily water intake in the sulfamethoxazole / trimethoprim group compared to the HydroTrim® group from 2 days before to 2 days after the treatment period, expressed as a percentage
Conclusion
Sulfamethoxazole-based water-soluble products provoke an immediate and continuous decrease in water intake throughout the treatment period in pigs, unlike HydroTrim® (sulfadiazine-trimethoprim).