Epidemiological characterization and risk evaluation associated with the presence of Phthiraptera in poultry farms from Minas Gerais, Brazil

Phthiraptera are lice highly adapted to living as permanent and obligatory ectoparasites of birds and mammals. High infestations by biting lice contribute to the low productivity, loss quality of the eggs, besides weight decrease of chickens. Therefore, this study aimed to evaluate and to characterize the risks involved with the presence of biting lice in laying chicken from Minas Gerais, Brazil, throught a Multiple Correspondence Analysis (MCA). A secondary database with information regarding 402 chicken houses from 42 properties of laying hens from the same region was used and adapted for this study. The variables that composed the correspondence model were selected through Chi-square tests (p ≤ 0.05). A risk index was designed to relate the presence of biting lice out of variables such as risk factors related to the presence of these ectoparasites. The MCA graphic designed to conduct the epidemiological characterization of the presence of biting lice presented a Chi-square accumulated value of 53.59%. There was an association between the risk index and the synanthropic birds, subsistence hens, presence of lice and other ectoparasites in shelters and ectoparasites control. These results provide knowledge about the Phthiraptera epidemiology. Besides that, this information may contribute to the decision-making process in order to reduce the risk of possible infestations in poultry farms and the negative effects of the infestations.