Page Banner

United States Department of Agriculture

Agricultural Research Service

Title: Comparison of Salmonella Enteritidis Infection in Hens Molted Via Long Term Feed Withdrawal Vs Full Fed Wheat Middling

Authors
item Seo, Kun Ho
item Holt, Peter
item Gast, Richard

Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 29, 2001
Publication Date: December 5, 2001
Citation: Seo, K., Holt, P.S., Gast, R.K. 2001. Comparison of salmonella enteritidis infection in hens molted via long term feed withdrawal vs full fed wheat middling. Journal of Food Protection.

Interpretive Summary: Salmonella Enteritidis (SE) is an important pathogen for the layer industry, primarily because of its ability to infect hens and ultimately contaminate egg contents. 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 fee for 10-14 days which hcauses the birds to cease egg lay for a period of time. Previous work showed that molting birds through feed removal increased the severity of a Salmonella Enteritidis (SE) infection. The current study was conducted to follow the progression of a SE infection in unmolted hens vs hens molted via 14-day feed removal or unlimited feeding of wheat middlings, in the presence or absence of 2.5% lactose administered in the drinking water. All molt procedures caused cessation of egg lay within 3-7 days. In two trials, birds subjected to total feed removal shed 1000-100000 logs more SE Ethan either the control birds (unmolted) or birds fed wheat middlings on days 4 and 10 post infection. Liver/spleen, ovary, and cecum counts were also significantly (P<0.05) higher in the fasted birds in one trial and liver/spleen and cecum counts in the second. These results indicate that there are alternative methods to long term feed removal which can be used to molt birds and not increase the risk for SE problems.

Technical Abstract: Salmonella Enteritidis (SE) is an important pathogen for the layer industry, primarily because of its ability to infect hens and ultimately contaminate egg contents. Studies have shown that stress situations such as flock recycling (induced molting) can increase SE problems in the flock. The current study was conducted to follow the progression of a SE infection nin unmolted hens vs hens molted via 14-day feed removal, or ad libitum feeding of wheat middlings, in the presence or absence of 2.5% lactose administered in the drinking water. In two trials of the experiment, all hens were infected with approximately 1000000 SE at day 4 of molt and sampled for SE shedding on days 4, 10, 17, and 24 post infection. In Trials 1 and 2, birds subjected to total feed removal shed 1000-100000 more SE than either the control birds (unmolted) or birds fed wheat middlings on days 4 and 10 post infection. Liver/spleen, ovary, and cecum counts were also significantly (P<0.05) higher in the fasted birds in one trial and liver/spleen and cecum counts in the second. No differences in any of the SE counts were observed in unmolted vs wheat middlings-fed birds. Lactose supplementation in drinking water did not provide any advantage in reducing SE infection in both trials. These results indicate that there are alternative methods to long term feed removal which can be used to molt birds and not increase the risk for SE problems.

Last Modified: 10/21/2014
Footer Content Back to Top of Page