Submitted to: Journal of Applied Poultry Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/2/2005
Publication Date: 1/1/2006
Citation: Murase, T., Miyahara, S., Sato, T., Otsuki, K., Holt, P.S. 2006. Isolation of salmonella organism from commercial layer houses where the flocks were molted using a wheat bran diet.. Journal of Applied Poultry Research. 15 :116-121. Interpretive Summary: Induced molting is a procedure used by 60-70% of the layer industry to achieve a second egg laying cycle from their flocks. A molt is generally induced through the removal of feed for 10-14 days which cause the birds to cease egg lay for a period of time. Previous work showed that molting birds through feed removal increased the severity of Salmonella enteritidis (SE) infections while molting hens by feeding them wheat middlings (WM) did not. The current study examined if WM could be used in a commercial situation to molt hens. Compared with the fasted hens, egg production post molt was generally better in the WM molted hens and isolation of environmental salmonellae was generally lower. These results indicated that there are alternative methods to long term feed removal that can be used to successfully molt hens while not increasing the risk for SE problems.
Technical Abstract: A flock comprising approximately 26,000 commercial laying hens reared in an environmentally controlled windowless house, was given wheat middlings (WM) for 25 days (trial 1) or treated with the WM for 21 days and then were given a mixture of the WM and the layer feed (1:1 (w/w)) for the last 4 days of the treatment (trial 2). After that, the birds were again fed with their normal layer feed. Photoperiod was reduced from 16 hours to 9 hours in both trials. Most of the birds in both trials ceased egg production by 10-15 days of the treatment. The mean production during 61-120 days exceeded 86% in both trials. In 3 additional flocks molted via 11- or 12-day feed deprivation, the mean egg production during 61-120 days ranged from 74.5-82.5%. Mortality observed in the flocks with WM treatments did not exceed that for the flocks molted with feed removal. The houses in the farm were naturally contaminated with several Salmonella enterica serovars. In rooms where the flocks were subjected to feed deprivation, isolation of Salmonella suddenly increased when the hens went completely out of egg production while no increase in the isolation rate was found during the WM treatment. The study demonstrated that feeding of WM was successfully used as an alternative to feed withdrawal to improve egg production in aging hens in a commercial egg-production setting.