Monitoring of heamatological indices in a sample group of cats subjected to serial blood collections for bioequivalence testing.

The bioequivalence evaluation of a drug is based on the bioavailability of its active molecule. Serial blood sampling might be limited in cats, due to their reduced blood volume and other morphophysiological characteristics that will be analyzed in this study. The bioequivalence testing of an antihelmintic product was conducted on 37 common breed cats, between 2 to 4 kg, fed with dry and canned food. The testing protocol consisted of two phases, 14 days apart. Eleven blood samples were collected at increasing time periods (024h). The total blood volume collected in each stage was evaluated based on the volemia, estimated at 7.5% from the total body weight, representing a maximum of 13 ml/kg and 2.2 ml for each sample. Along with the serial blood sampling, at the start and ending of the two phases, haematological evaluations (on EDTA) and biochemical profiles (on Li-Heparin) were performed. Addtionally, morphological assessments were carried out on panoptic stained smears. No major alterations of the physiological parameters were recorded, except for a small decline in the erythrocitary parameters, associated with oscillations of the total white blood cell count and a tendency to monocytosis. The results of this study reveal the necessity to associate physiological parameters of the tested animals with the requirements of drugs bioequivalence testing protocols, in order to respect ethical and good practice standards while collecting multiple blood samples.