THE EFFECTS OF DIFFERENT BEAK TRIMMING TECHNIQUES ON PLASMA CORTICOSTERONE AND PERFORMANCE CRITERIA IN SINGLE COMB WHITE LEGHORN HENS

Authors: DAVIS, G - DEPT POULTRY SCI, NC; ANDERSON, K - DEPT POULTRY SCI, NC; Jones, Deana

Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/22/2004
Publication Date: 9/1/2004
Citation: Davis, G.S., Anderson, K.E., Jones, D.R. 2004. The effects of different beak trimming techniques on plasma corticosterone and performance criteria in single comb white leghorn hens. Poultry Science. 83:1624-1628

Interpretive Summary: Beak trimming is a common practice in the commercial egg industry. While the process of beak trimming serves the beneficial purpose of reducing cannibalism and feather pecking in commercial layer flocks, it has been under the scrutiny of some animal rights groups as an inhumane practice. The current project was undertaken to determine the physiological effects of beak trimming on the laying hens. A flock of laying hens was equally divided into one of three treatments: non-trimmed controls, precision beak trimming at six days of age or block beak trimming at 11 weeks of age. Physiological indicators of immediate stress responses were elevated above those found in the controls for both beak trimming treatments. Birds which were beak trimmed at 6 days of age did experience reduced body weight and feed consumption compared to the controls until 8 weeks of age. After the 11 week block beak trimming, body weight was reduced compared to the controls until through 16 weeks of age. There were no differences in livability among any of the three treatments. Both beak trimming treatments resulted in better egg income, feed cost per hen and net income. Also, both of the beak trimmed treated hens exhibited lower fearfulness levels and better feather coverage at the end of the production cycle (78 weeks of age). It was determined that beak trimmed hens can adapt to the physiological stress of beak trimming and perform at a greater level of egg production compared to non-trimmed controls.

Technical Abstract: One-day old DeKalb XL chicks were given a six d (6DP) beak trim using a 2.8 mm gauge and an 11 wk beak trim (11WB) using a block cut approximately 2 mm anterior to the nasal openings. Corticosterone (CS) levels of the 6DP treatment were significantly (P < 0.01) elevated above non-trimmed CS levels at 2 h post-trim; and BW and feed consumption (FC) of the 6DP were depressed until eight wk of age. At 11 wk of age, CS of the 11WB treatment was significantly (P < 0.02) elevated above controls at 2, 8, 168, and 840 h post-trim. The 11WB treatment resulted in a decrease in FC and a reduction in BW at 12, 14, and 16 wk of age while there were no differences among treatments in livability during the pullet phase. At 72 wk of age, FC of the non-trimmed controls was greater than both beak trimmed treatments, and both beak trimmed treatments had greater hen housed eggs, percentage hen day egg production, and percent livability. Both beak trimmed treatments resulted in better egg income, feed cost per hen, and net income (NI). The 6DP and 11WB beak trim treatments resulted in an improvement of NI per hen of $1.48 and $1.86, respectively. In addition, both beak trimmed treatments exhibited better feather score and Hansen's Test (fearfulness). It was concluded that pullets and hens can adapt to the physiological stress of beak trimming and out perform non-beak trimmed controls during a lay phase.