The evaluation of hepatic diseases in cats requires many laboratorial tests, and those routinely used are less conclusive. Considering the little availability of data and controversies related to the subject, we decided to study the preprandial and postprandial serum bile acids and plasma ammonia levels, and the effects of storage on these values. Preprandial (fasting) and postprandial serum bile acid (SBA) levels of 20 adult, healthy cats were determined using the enzymatic method. The measured values were 0.5 ± 0.1 and 3.6 ± 1.0 µmol/L, respectively. The preprandial and postprandial plasma ammonia (PA) levels, obtained 30 minutes after blood collection, 157.0 ± 18.7 µg/dL or 89.5 ± 10.7 µmol/L and 295.3 ± 28.2 µg/dL or 165.2 ± 17.3 µmol/L, were determined using the ion-specific electrode method, showing significant difference. However, this difference was not observed when the ammonia levels were measured in plasma samples kept under frozen storage (-20ºC) during 24 and 48 hours. These results suggest that the plasma samples should not be stored for further ammonia level determination. The SBA and PA levels measured for healthy cats in this study can be compared to those obtained from cats under suspicion of liver disease, helping to establish the diagnosis and prognosis.
Bile acids; Ammonia; Cats
