Aspirin products (salicylates) are widely used in the rearing of swine mostly for fever and inflammation reduction in the case of infectious disease, but also for less-descript reasons such as maintenance of water and feed intake and maintenance of general health throughout the growing period.
The salicylates play an important role as a non-steroidal, anti-inflammatory drug in swine production systems worldwide. Because of their immunomodulatory, analgesic, antipyretic, and anti-inflammatory activities, they are commonly used as an aid in the treatment of swine disease. Other effects have been reported such as minimizing the effects of heat stress, and enhancing growth performance, feed utilization, nutrient digestion and absorption and the quality of meat.
Because data are lacking that supports the pharmacokinetic differences between sodium salicylate and liquid aspirin when administered orally via the drinking water to swine, a study was developed with the goal of determining appropriate plasma levels within the first twenty-four hours of using Oral-Pro® Sodium Salicylate 48.6% (OPSS 48.6%) and Liquid Blue Aspirin12.5% (LBA 12.5%) when administered according to label directions.
Materials and Methods
The study was divided into two phases. All pigs were weighed at the beginning of each phase. Oral-Pro® Sodium Salicylate 48.6% (Aurora Pharmaceutical, Inc.) was administered by single oral dose at the rate of 3.23 ml per 100# body weight. Liquid Blue Aspirin 12.5% was administered orally by single oral dose at the rate of .97 ml per 100# body weight.
Phase I: Pigs were assigned to Treatment 1 and treated with OPSS 48.6% by a single oral dose for 1 day. Additional pigs were assigned to Treatment 2 and treated with LBA 12.5% ASA by a single oral dose for 1 day. Blood collections occurred at the same time points as with Treatment 1. (See Figure 1)
Phase II: After a 4-day washout period, pigs were weighed on the first day of Phase II. Pigs were assigned to treatment with LA 12% by single oral dose at the same dosage rate as in Phase I and the same sample time points. Additional pigs were assigned to treatment with OPSS 48.6% by single oral dose at the same dosage rate as in Phase I and the same sample time points. (See Figure 2)
- Sodium Salicylate 48.6%-treated animals reached therapeutic blood levels within 15 minutes of treatment and maintained above therapeutic levels for about 5 hours.
- Liquid Blue Aspirin12.5%-treated animals didn’t achieve therapeutic blood levels at any of the time points measured.
- The average blood level of salicylate achieved over the 24-hour testing period in the Sodium Salicylate 48.6%-treated animals were above therapeutic levels.
- The average blood level of salicylate achieved over the 24-hour period in the Liquid Blue Aspirin12.5%-treated animals was well below therapeutic levels. (See averages of both Phase I and Phase II study results in Figure 3)
Water treatment with Oral-Pro® Sodium Salicylate 48.6% provides quicker and longer lasting therapeutic blood levels than Liquid Blue Aspirin 12.5% resulting in improved reduction of fever and inflammation in swine.