Research note: Mite infestations in non-descriptive indigenous chickens in Bangladesh: Present status and pathology

Non-descriptive, indigenous chickens (NDICs) in Bangladesh are commonly reared in scavenging system. Here, we describe the prevalence and pathological impacts induced by mite infestations in NDICs. We found that 47.4 % of NDICs (185 out of 390) were infested with three species of mites namely Trombicula spp. (53.1 %), Knemidocoptes mutans (scaly leg mites/SLM, 15.1 %) and Dermanyssus gallinae (red mites of poultry/PRM, 2.8 %). Sex, age and seasons significantly (p < 0.05) influenced the prevalence of mite infestations. Trombiculid mites produced more specific lesions characterized by circumscribed disc-shaped notches with attached bright red colored mites, which were commonly found in breast, fluff and thigh. Destruction of the epidermis, proliferation of fibrous connective tissues along with massive infiltration of heterophils and lymphocytes were predominant. Thick, rough and ragged appearances with encrustation of the skin of leg were found grossly in SLM infestations. Histologically, hyperkeratosis, acanthosis, massive infiltrations of reactive cells and cross-sections of parasites were detected. PRM induced petechial hemorrhages, papules, necrosis, rupture of the feather follicles and scab formations. Hyperkeratosis and huge infiltration of mononuclear cells and granulocytes were evident. Taken together, mite infestation is a big challenge in profitable NDICs rearing in Bangladesh and warrants immediate attention for their control.