Effect of Foot Pad Dermatitis on Production Performance,Egg Quality,Behavioral Responses,and Immune Levels of Laying Hens in Furnished Cages
Foot pad dermatitis(FPD)is a contact dermatitis affecting the claw and toe surfaces of poultry.FPD is one of the most common paw-toe health problems,with negative effects on the welfare and health of poultry.This study aimed to explore the effects of FPD on production per-formance,egg quality,behavioral responses,and immune levels of laying hens in the furnished cages.In this study,60 Hyline Brown laying hens with 48 weeks of ages(WOA)were randomly selected.After four-point scoring,that score 0 for no lesions on the foot pads,score 1 for exces-sive keratosis,a small lesion of the foot pad epithelium with redness or discoloration,score 2 for foot pad dermatitis with epidermis discoloration,cutaneous lesions slight to erosion;score 3 for bumble foot with swelling of the foot pad visible from dorsal view.Bird was raised in furnished cage until 55 WOA.Performance and egg quality of laying hens were recorded and video-recorded for 2 consecutive days at 51 and 55 WOA.Then,the tonic immobility(TI)tests and open field tests(OFT)were carried out.Finally,the expression of immune-related factors in the skin,spleens,livers,small intestines,and serum of hens were detected.We found that FPD had no significant effect on the production performance(P＞0.05),but improved the body weight com-pared with the score 0 group(P＜0.05),and the protein height and Haugh Units were signifi-cantly reduced for hens at 51 WOA(P＜0.05).Behavioral observations showed that FPD re-duced the expression of preening behaviors in laying hens(P＜0.05).However,there was no significant effect on other event behaviors(object pecking,toe pecking,pacing,comfort behav-iors)(P＞0.05).The results of behavioral tests showed that FPD had no significant effect on re-sponses of fear and anxiety in laying hens(P＞0.05).The relative mRNA expressions of im-mune cytokines(IL-2,IL-4,IL-6,IL-8,IL-10,IL-17,IL-1β,IFN-γ,and TNF-α)and immuno-globulin IgA and IgG in foot,liver,and spleen tissues were significantly increased in hens with FPD(P＜0.05).The concentrations of IL-4,IL-6,IFN-γ,and TNF-α were also increased in the serum(P＜0.05).FPD had no significant effect on the production performance of laying hens.FPD decreased the expression of preening behavior and increased the expression of immune-related factors in the skin of the paw toe,which might lead to the chronic inflammation of laying hens.
foot pad dermatitislaying hensproduction performanceegg qualitybehaviorsimmune responses
万方数据
维普
