Evaluierung von Kleingruppenhaltungssystemen und ausgestalteten Käfigen hinsichtlich Brustbeindeformationen, Gefiederstatus, Krallenlänge und Körpermasse bei den Legelinien Lohmann Selected Leghorn und Lohmann Brown

Abstract

Abstract. Title of the paper: Evaluation of small group housing systems and furnished cages concerning keel bone deformities, plumage condition, claw length und body weight in layer strains Lohmann Selected Leghorn and Lohmann Brown Small group housing systems (Eurovent 625+a-EU) and furnished cages (Aviplus und Eurovent 625A-EU) were evaluated for the occurrence of keel bone deformities, plumage condition, claw length and body weight. The examinations were performed in two layer strains, Lohmann Selected Leghorn (LSL) and Lohmann Brown (LB), over two laying periods. In addition, the effects of layer strain, month of laying period, rearing method, group- size and body weight on these traits were tested. The assessments based on a scoring system comprising the scores 1 (very severely defective part of the body) to 4 (intact part of the body) were performed every three months during the laying period. Examinations of keel bone condition and measurements of body weight were performed in a total of 864 hens, claw length and plumage condition were examined in a total of 720 hens. Housing system showed a significant effect on the incidence of keel bone deformities and claw length. Plumage condition was significantly affected by group size, whereas plumage condition was worst in groups of 20 hens in Aviplus and in groups of 10 hens in Eurovent 625A-EU. Concerning claw length there were significant differences between diverse claw abrasives. The strongest abrasion was found in groups with two abrasive blocks, whereas perforated metal plates led to the least abrasion. Month of laying period showed a significant effect on each examined trait with a decrease in keel bone and plumage condition and an increase in claw length and body weight during the laying period.