Determinants influencing prevalence of louse infestations on layers of district Faisalabad (Pakistan).

1. This paper describes the influence of some epidemiological determinants on the prevalence of louse infestation on layers in Faisalabad (Pakistan). 2. Seventy layer farms were screened to determine the prevalence of louse infestation and its determinants including age of the bird, availability of space per bird and frequency of litter change. Prevalence of Lipeurus caponis was highest (53.2%), followed by Menacanthus stramineus (22.16%), Goniodes dissimilis (12.37%) and Goniodes gallinae (12.37%). 3. Older birds (36 to 74 weeks of age) were found with a significantly higher prevalence of louse infestation than younger birds. 4. Month-wise prevalence of louse infestation was higher during the summer months (from April to August) and at older age. 5. Birds kept at floor area allowances ranging from 0.43 to 0.55 m(2) were highly infested with lice as compared to those provided with a space of 0.61 m(2) or higher per bird. 6. Litter change frequency after every 8 weeks resulted in a reduced chance of louse infestation as compared to less frequent litter changing practice. 7. It was concluded from the study that the louse infestation is a menace for the poultry production industry in Pakistan and age, space per bird and litter change frequency are the influencing determinants. 8. Further research on the chemotherapeutic trials and resistance in poultry should be continued for an effective lice control program.