Histopathological Study on Fibrous Layer of Hydatid Cyst in Camel, Cattle and Sheep

Hydatid cyst almost is caused by Echinococcus granulosus. Due to probable differences in fibrous layer of cyst, our main objectives were to investigate any difference of fibrous layer of hydatid cyst in camel, cattle and sheep, using histopathological methods.
For each kind of animal, 22 samples including hydatid-cyst-infected livers and/or lungs were collected from Isfahan City abattoirs (Iran) during April to June 2016. A specimen of about 1 cm2 of fibrous layer was taken, and underwent usual pathologic processing and analyzing.
Findings: Overall, 138 pathological sections were examined. The diameter size range of the cysts was 1.5-6.0 cm in camel and cattle and 0.5-2.0 cm in sheep. Cattle have maximum sterile cyst. The average age was 9, 6 and 3 years for camels, cows and sheep, respectively. The fibrous capsule presented in all 66 studied animals (100%). The necrosis was seen in 20 animals (30.3%), 12 cases in camels’ lung, 6 cases in cattle’s lung and only 2 cases in sheep (1 case in lung and 1 case in liver). There was only one 1case of granuloma (1.52%) in cattle’s liver.
There were some differences in fibrous layer of hydatid cyst in camel, cattle and sheep. The severity of pathologic changes led to necrosis and granuloma were different in these animals and the relative frequencies as well. It may be due to hosts’ types, parasites’ strains and average age of host. More investigation is required.