Evaluating the Effect of Acetylsalicylic Acid in Turkey Poults Experimentally Infected with Coccidia

Acetylsalicylic acid (ASA), originally trademarked as Aspirin, is a common nonsteroidal anti-inflammatory drug (NSAID) used in human and veterinary medicine to mitigate pain and pyrexia caused by inflammatory processes. There is limited information on the effectiveness of ASA in turkey production. The objective of this study was to investigate the effect of ASA on turkey poults with induced coccidial enteritis. Two experimental trials were conducted. In both trials, the turkeys were divided into four groups: no coccidia + no ASA; no coccidia + ASA (NA); coccidia + no ASA (CN); and coccidia + ASA (CA). In both trials, turkeys in groups CN and CA were given 100× the dose of a commercial turkey coccida vaccine. Starting 48 hr postinoculation and for 7 days, the turkeys from groups NA and CA were given ASA (50 mg/kg per day). For Trial 1, ASA was given via oral gavage twice daily, whereas in Trial 2 (T2), ASA was in the drinking water. Poult weights and cloacal temperatures were recorded daily. Blood was collected daily from two randomly selected birds from each group for biochemical analysis and to assess the serum salicylic acid and nitric oxide (NO) levels. At the end of the trials, tissues were examined histologically, and immune gene expression was evaluated. Coccidia infection was the factor that had most significant influence on the majority of measured parameters. ASA had minimal to no effect on reducing clinical signs, minimizing weight loss, or controlling body temperature. These findings may be due to the rapid elimination of the drug or because sick birds did not consume sufficient ASA. In T2, it was estimated that the CA group poults consumed 31 mg/kg of ASA or less per day. Although the drinking water concentration was calculated to match the total daily intake (50 mg/kg per day), ASA's rapid metabolism meant that continuous low-level ingestion might not have reached the therapeutic plasma threshold achieved by two to three daily bolus doses. Because ASA is rapidly metabolized, a higher total daily dose may be required when provided in drinking water to maintain effective serum concentrations compared with bolus administration. Although the serum NO and tissue gene expression analysis showed that coccidia infection predominantly induces an inflammatory response, the anti-inflammatory effect of ASA administered to birds in the NA or CA groups were nil to minimal. This study highlights the complexity of ASA's effects on turkeys.