Measuring Biochemical Variables and Serum Amyloid A (SAA) in Working Mules in Central Italy

SIMPLE SUMMARY: Mules are thought to be stoic animals that generally express few signs of illness or disease. Mules used as working equids in strenuous conditions on a daily basis may not show clinical signs of disease until the disease is more advanced. The help of stable side tests and measuring variables such as acute phase proteins, which are known to elevate in a rapid manner due to infection or inflammation, may assist owners and practitioners with detecting early signs of disease in working mules. This study measured serum amyloid A (SAA), an acute phase protein, in 10 healthy working mules in Central Italy. The study found no change in SAA for mules working 8 h but mild increases in serum electrolytes, urea, and creatinine concentrations that supported a loss of body water and decreased renal blood flow in response to exercise. ABSTRACT: According to FAO reports, the global mule population counts about 9 million mules. This hybrid cross of a male donkey and a female horse is mainly used for draft purposes because they are thought to be strong and hardy animals. Most consider mules to be less susceptible to disease and fatigue compared to horses. Therefore, the aim of this study was to investigate the effects of fieldwork on biochemical variables and serum amyloid A in working mules. Blood samples were collected from 10 healthy, female, working mules before and after 8 h of fieldwork. According to statistical analysis, a significant influence (p < 0.05) of fieldwork was found on mules’ electrolyte profile with increased levels of sodium, chloride, and calcium, as well as on blood urea nitrogen and creatinine. After a day of fieldwork, serum sodium, chloride, calcium, urea, and creatinine concentrations were increased, supporting decreases in body water and renal blood flow. However, without comparison to a group of mules that were not exercised yet maintained under similar ambient conditions, it is uncertain whether these changes can be attributed to exercise. Further, no change in SAA concentration was found after exercise, indicating that the work performed did not result in systemic inflammation.