|Marchant Forde, Ruth -|
|CHENG, HENG WEI|
Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 31, 2010
Publication Date: December 1, 2010
Citation: Marchant Forde, R., Cheng, H. 2010. Different effects of infrared and one-half hot-blade beak trimming on beak topography and growth. Poultry Science. 89(12):2559-2564. Interpretive Summary: Beak trimming is a procedure performed to reduce or eliminate inter-bird feather pecking and cannibalism in farmed birds. In laying hens, beak trimming is typically performed at 7-10 days of age using a hot-blade trimmer which cuts and cauterizes the beak to prevent any postprocedure bleeding. There has been much debate and research concerning the relative effects of hot-blade trimming on pain and welfare, and as a result producers are keen to adopt and implement less painful ways of trimming birds. One such method, infrared beak treatment is purportedly a more acceptable, more welfare friendly alternative that is increasingly being used within the industry. This approach uses high intensity heat that penetrates down through the beak’s corneum layer to the corneum generating basal tissue and inhibits further germ layer growth. After treatment the corneum layer remains intact until 7-10 d post-trimming after which the tip of the beak begins to soften and erode away with use. The goal of current research was to examine the effects of infrared treatment, relative to hot-blade trimming, on pain and feeding ability post procedure. To achieve this we used three groups that were either hot-blade trimmed, infrared treated, or left as intact beak controls. At fixed intervals following trimming we examined beak morphological changes and tested the birds’ motivation and ability to feed. Infrared birds showed an improvement in performance and a reduction in stress levels. Improved beak trimming methods will enhance bird welfare with subsequent improvements in consumer perception of the poultry industry. The information provided in the article should be useful for farmers to develop breeding programs and for scientists to plan or interpret their studies.
Technical Abstract: This study examined the effects of infrared beak treatment (IR) and hot blade beak trimming (HB) on beak length and production in laying hens. Seventy-two day-old layer chicks were randomly assigned to HB, IR or a control (C) group. Chicks were pair housed by treatment, and beak images and production indices were obtained post-treatment and at fixed intervals for 10 weeks. All beaks were shaped normally at the onset of the study and no perceptible treatment-related differences in shape occurred over time (P > 0.05). Different trimming methods did, however, result in: varying proportions of trimming across treatments (P < 0.01) and different beak re-growth rates (P < 0.01). Immediately after treatment, HB beaks were significantly shorter than C or IR beaks (P < 0.01) and remained shorter than C beaks for the duration of the study (P < 0.01). C and IR beaks remained comparable in length until the onset of tissue degeneration and erosion of the IR beaks at 1 to 2 weeks post-treatment. At week 2 post-treatment, beaks were longest in C, intermediate in IR and shortest in HB birds (P < 0.01). Thereafter, there was an increase in beak length in all treatments over time (P < 0.01) but HB birds had greatest re-growth. HB birds’ beak length became similar to that of IR birds from week 3 to 8, and then became longer at week 9 and 10 post-treatment (P < 0.01). By week 10, HB beaks were about 20% shorter while IR beaks were 35% shorter than C beaks (P < 0.01). The effects of treatments on body weight (BW) emerged at day 5 post-treatment. Body weight in HB birds was suppressed up to, and including, week 9 post-treatment relative to C birds (P < 0.05), and was significantly lower than that in the IR birds between 2-4 weeks (P < 0.05). Infrared treated birds did not differ from C birds after week 3 post-treatment (P < 0.05). By the final week of the study, there were no longer any apparent differences in BW across treatments (P > 0.05). For the most part, feed intake (FI) was higher in C birds, intermediate in IR birds, and lowest in HB birds until week 9 post-treatment (P < 0.05). Similarly, feed waste was generally higher in C birds and least in the HB birds (P < 0.05). It appears IR was more effective at inhibiting beak re-growth with a less pronounced impact on production and growth than HB.