The first portion of this trial was designed to compare the solubility of two common liquid aspirin products – namely an acetylsalicylic acid and a sodium salicylate product. While the solubilities of these products are documented, the goal was to determine if under common commercial settings the solubility affected how much of the product would be taken up by the water medicator. Therefore, stock solutions were mixed at a set concentration and placed under nursery conditions. The stock solutions were then sampled at four different time points. The samples were then analyzed to determine the amount of active ingredient present at each time point. The results indicated that the sodium salicylate product was more soluble, resulting in a higher concentration of active ingredient in the samples at all time points. Because the sodium salicylate product could deliver a higher concentration of active ingredient to the pigs it was used in the remainder of the trial. The fact that the sodium salicylate product can deliver more active ingredient doesn’t necessarily imply that it should be used instead of acetylsalicylic acid products because the amount of aspirin that is beneficial is still unknown. If the amount of aspirin needed to reduce fever and pain enough to keep pigs on feed during a viral infection is relatively small, then either product would reach appropriate concentrations through the water medication system.
The second portion of the trial focused on administering aspirin at various stock solution concentrations and then measuring the resulting concentration of aspirin that was in the pig’s blood. This is an important step in determining what dose of aspirin is beneficial, as information on drug absorption and distribution, two major factors in dosage determination, are unknown for this administration system in the pig.
The results indicate that the sodium salicylate product, when given orally through a water-medication system, is absorbed and reaches measurable concentrations in the blood.
Although co-variables, such as water quality, equipment types, and management styles (including vaccination and treatment protocols) must be taken into account when extrapolating this data to other production situations, the results of this trial can be used in future studies to develop dosage recommendations.
In conclusion, this study showed that (1) there are significant differences in the acetylsalicyclic acid and sodium salicylate product solubility which may lead to differences in dosage recommendations and (2) sodium salicylate, when given orally through a water-medication system, is absorbed and reaches measurable concentrations in the blood.
