Comparison of liver and bone health of two laying hen strains kept in different cage systems

Abstract

Concerns have been increasing about conventional cages for laying hens in connection with welfare. Liver and bone disorders of laying hens are major problems. Therefore, the aim of this experiment was to investigate the differences in liver and bone traits of two laying strains kept in conventional and enriched cages. A total of 532 two Lohmann Brown Classic (LB) and 532 Lohmann LSL Classic (LW) hens were housed from 16 to 73 weeks in either conventional cages or enriched cages. Enriched cages had a nesting area, scratch pad, perch and claw shortener. At 73 weeks of age, blood parameters (alanine amino transferase (ALT), aspartate amino transferase (AST), alkaline phosphatase (ALP), calcium (Ca), phosphor (P), cholesterol and triglycerides), relative liver weight, fatty liver score and bone parameters (weight, length, diameter, maximum load, deformation at maximum load and stiffness of tibia and femur) were determined. The cage type affected only serum ALT, AST, ALP and cholesterol levels. Differences of liver and bone parameters between both cage types were not statistically significant. Serum ALT, ALP and P level and also weight and diameter of examined bones were affected by strain. This study indicates that cage type and cage type x strain interactions have limited effect on the liver and bone health.