|Byrd, James - Allen|
|Nisbet, David - Dave|
Submitted to: Poultry Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 2/16/2006
Publication Date: 6/5/2006
Citation: McReynolds, J.L., Moore, R.W., Kubena, L.F., Byrd II, J.A., Woodward, C.L., Nisbet, D.J., Ricke, S.C. 2006. Effect of various combinations of alfalfa and standard layer diet on susceptibility of laying hens to Salmonella enteritidis during forced molt. Poultry Science. 85:1123-1128. Interpretive Summary: Salmonella bacteria can cause illness and death in humans consuming contaminated poultry products. Poultry eggs may become contaminated with Salmonella after the molting process. In this study, we looked at combining an alfalfa diet or a combination of alfalfa and a corn soy diet for their effectiveness in reducing Salmonella during an induced molt. Supplemental diets such as alfalfa have been shown to help keep the bacterial populations balanced in the gastrointestinal tract during a molt. When the birds were treated with these products, Salmonella was reduced in the bird. This finding is important because it will aid in designing management practices to reduce or prevent contamination of eggs and egg products by Salmonella bacteria.
Technical Abstract: Feed deprivation is commonly used by the poultry industry to induce molting and stimulate multiple egg-laying cycles. However, feed deprivation has been observed to increase susceptibility to Salmonella infections. Previous studies indicated that alfalfa was efficacious in reducing Salmonella; the present investigation was designed to evaluate the efficacy of combined alfalfa and layer diets on Salmonella colonization. Leghorn hens over 50 wk of age were divided into groups of 12 hens and placed in individual laying cages. One wk prior to dietary changes, hens were put on an 8-h light and 16 h-dark photoperiod that continued for the 9-day experiment. Hens were challenged orally with 10**4 cfu of Salmonella enteritidis (SE) on d 4 of treatment, and cultured for SE at the termination of the study (d 9). Two independent experiments were run consisting of the following treatment groups: non-fed hens (NF), full-fed standard commercial layer diet (FF), 100% alfalfa meal diet (ALF), a 90% alfalfa meal/10% standard commercial layer diet (ALF90), a 70% alfalfa meal/30% standard commercial layer diet (ALF70). When evaluating SE colonization in the ceca (Exp.1) a reduction (P < 0.05) was seen in the ALF and ALF70 treatment groups compared to the controls with Log10 values of 0.54, 0.44 and 2.82 respectively. When evaluating physiological parameters the alfalfa treatment groups had reductions (P < 0.05) in weight loss, ovary weight and feed consumption when compared to the FF hens and these results where comparable to the NF hens. In Exp.2 all of the treatment groups had a reduction (P < 0.05) in SE colonization of the ceca. There were also similar physiological reductions (P < 0.05) in weight loss, ovary weight and feed consumption when birds were fed the alfalfa diets in Exp 2. These data suggest that alfalfa can potentially be combined with layer ration to limit SE infection and still induce a molt comparable to feed withdrawal.