The influence of Dermanyssus gallinae and different lighting regimens on selected blood proteins, corticosterone levels and egg production in layer hens.

Egg production in battery cage systems in commercial poultry farms promotes uncontrolled growth of poultry ectoparasite Dermanyssus gallinae. Intermittent lighting regimens provided a promising alternative for controlling D. gallinae invasions. The study analysed the influence of D. gallinae invasions on selected blood protein fractions (albumin, α-, β-, γ-globulin), corticosterone levels and egg production in Hy-Line Brown layer hens exposed to two lighting regimens: A (16 L:8D) and B (intermittent (4 L:2D); L-light, D-dark). Blood samples were collected from a total of 48 hens (divided into uninfested - UF, and infested - IF groups for each lighting regimen). The concentrations of protein fractions were analysed by electrophoresis on Cormay Gel Protein 100, and corticosterone levels were determined in a radioimmunoassay. The results of the study revealed concentrations of β-globulin and corticosterone levels were significantly higher in IF than UF groups in both lighting regimens. However, both parameters were higher in hens exposed to lighting regimen B than lightening regimen A. Gamma-globulin concentrations were significantly lower in IF than UF groups in both lighting regimens. Egg production was significantly lower in all groups than commercial standard. D. gallinae and intermittent lightening regimen had interaction effect on the corticosterone level in hens. Strong decreasing (negative) linear relationship between corticosterone levels and egg production (r = -0.911) was reported.