A Simple Spectrophotometric Method for Coccidian Oocysts Counting in Broiler Feces.

Abstract

This study aimed to develop a rapid spectrophotometric method for counting coccidian oocysts in broilers feces, based on a standard count method "Malassez cell". Therefore, a raw suspension containing purified oocysts of Eimeria known to parasitize broiler chicken was used. Five concentrations of oocyst suspensions were prepared, and three series of counts using the proposed method were compared with the conventional protocol using Malassez cell to quantify oocysts. Calibration curves were drawn to correlate the specific absorbance measurement at 550nm and the number of coccidian oocysts quantified using Malassez cell counting (oocysts mL-1). The obtained results allowed to establish a formula for an easy estimation of the cell count based on their respective absorbance. The developed method can be used not only for the in vitro evaluation of the anticoccidian activity of natural or synthetic substances, but also for assessing oocysts production and the level of coccidian infection in broilers. The estimation formula has been found to be satisfactory and useful for a wide range of Eimeria oocyst suspension, offering a methodology with high potential for automation in anticoccidian tests in vivo and in vitro.