Abstract

The study was designed to identify Cryptosporidium oocyst with the determination of infection rate in the faeces of local backyard chicken in Ninevah governorate. One hundred and forty freshly voided fecal samples were randomly collected from both sex of local hens aging between 6-12 months old. These samples were taken from ten various regions of the governorate from the 1^st Oct. 2010 till 1^st Oct. 2011. Two techniques were applied in this study, hot modified acid – fast stain was used to define the parasite species, while iodine stain was followed for determination the infective rates. Using hot modified acid – fast stain, C. baileyi was diagnosed and identified based on the measurements and diameters of the oocyst using ocular micrometer. Such dimensions were (4.6 × 6.2) micron containing four sporozoites. Out of 140 fecal samples, only 59 samples harbored the oocyst parasite in a percentage of 44.5% hens more than 6 month-one year ages and 33.2% for less than 6 months. However, higher infection rates were noticed in the females which were 45% versus 17.9% in the males. The infection rate was variant among different places which ranged between 25% and 55.6 %. There were significant statistical differences (P<0.05) in the infection rates of the geographical regions of the governorate.