Prevalence and Factors Associated with Biting Lice Infestation in Subtropical Goats

Background - Pediculosis and skin disorders are commonly observed in goats in subtropical regions, such as Hong Kong. Literature about pediculosis and its associated factors in subtropical goat farming is scarce. Objective - To determine the prevalence and identify factors associated with biting lice infestation in subtropical goats. Animals - 309 goats were selected from 17 farms that were clients of the veterinary ambulatory service (City University of Hong Kong), using a stratified random sampling design. Methods - This cross-sectional study was conducted from January to March 2025. The presence of lice, individual-level (e.g., skin lesions and hair coat condition) and herd-level factors were recorded by a single trained assessor via visual inspection and a questionnaire. Lice identification was confirmed by microscopy. Factors associated with biting lice infestation were identified using multivariate logistic regressions (Significance: P < 0.05). Data are presented with odds ratios and 95% confidence intervals. Results - The prevalence of biting lice infestation was estimated at 54.0% (167/309) and was positively associated with herd size (23.44 [8.83; 69.04], P < 0.001), skin lesion (17.85 [3.92; 98.35], P = 0.03), and poor hair coat condition (2.25 [1.24; 4.14], P < 0.001). In contrast, the presence of biting lice was negatively associated with the presence of sucking lice (0.01 [0.006; 0.09], P < 0.001). Conclusion and Clinical Importance - In subtropical regions, poor hair coat condition and skin lesions may serve as indirect clinical indicators of biting lice infestation in goats.