INFLUENCE OF SEQUENTIAL FEEDING AND FREE CHOICE FEEDING OF WET AND DRY WHOLE WHEAT ON LEG PROBLEMS IN BROILER CHICKS

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1 PE_2012sp49_1 INFLUENCE OF SEQUENTIAL FEEDING AND FREE CHOICE FEEDING OF WET AND DRY WHOLE WHEAT ON LEG PROBLEMS IN BROILER CHICKS Hamed Dadgar 1 *, Majid Toghyani 1, Amin Neamati 2 and Mohamad Dadgar Department of Animal Science, Khorasgan Branch, Islamic Azad University, Isfahan, Iran 2 - Young Researchers Club, Khorasgan Branch, Islamic Azad University, Isfahan, Iran *Corresponding author: nahr1362@yahoo.com ABSTRACT In this experiment the effects of sequential feeding and free choice feeding of wet and dry whole wheat on leg problems of broiler chicks was assessed. Four hundred and twenty broiler chicks were used in this study from 7 to 42 d. The treatments employed were: control, two different times of access (6 and 12 h) to wet and dry whole-wheat to alternate corn soybean diet and also ground wheat diet with free access to dry or wet whole-wheat in separate feeders. Tibial dyschondroplasia (TD), walking ability (gait score), foot pad dermatitis, femoral degeneration (FD), valgus/varus angulation, leg deformities and hock burn of broiler chicks were evaluated at 42 day of age. Tibial dyschondroplasia was not affected significantly by dietary treatments. The gait score was low in broilers in the group fed the 12 h sequential wet whole-wheat. Hock burn of broilers receiving dry and wet whole-wheat sequential feeding for 6 and 12 h were lower than control and free access to wet and dry whole wheat (P<0.05) birds. Broilers in dry whole wheat sequential feeding for 6 and 12 h had the lowest foot pad dermatitis (P<0.01). KEYWORDS: Broiler chicks; wet feeding; free choice; sequential feeding. INTRODUCTION Leg problems in domestic chickens are multifactorial in origin; causes include genetic age, predisposition, nutrition, management and environment (Hall, 2001). Leg problems include tibial dyschondroplasia, femoral degeneration, varus/valgus deformations, walking ability (gait score), foot pad dermatitis, hock burn, crooked toes, femoral head necrosis and ammonia burns. The most recent large-scale study found that 27.6 percent of the birds assessed close to slaughter age showed poor locomotion, and 3.3 percent were almost unable to walk (Knowles et al., 2008). Animal welfare aspects include the ability of affected birds to eat and drink (Garner et al., 2002; Sanotra et al., 2002) and the pain associated with the pathology of leg weakness. Lame broilers will preferentially select a ration containing an analgesic agent, more so than sound broilers (McGeown et al., 1999), which suggests that they are seeking pain relief associated with their leg abnormalities (Sorensen et al., 2000). Gait scoring surveys have shown that large numbers of broilers have impaired walking abilities and there is evidence that birds with score 3 or higher experience pain or discomfort (Scahaw, 2000).Other problems associated with the legs such as Tibial Dyschondroplasia, can be observed in chickens as late as 4 weeks of age. The weight of the bird compresses the legs causing painful lameness. Up to 30% of the flock can be affected; however, most birds show no clinical signs of the disorder. Both Angular bone deformity and Tibial Dyschondroplacia have been associated with rapid growth rate because the birds gain weight at a faster rate than the skeletal structure is able to mature. Droual et al. (1991) reported angular limb deformity of the valgus/varus type 154, World s Poultry Science Journal, Supplement 1, Expanded Abstract - Poster Presentation - Poultry and Welfare Environment

2 is the most common long bone distortion seen in broilers. It involves either outward or inward angulation of the limb at the intertarsal joint. Values of up to 20 may be considered normal, but can almost double in deformity (Hunter et al., 2008). Foot pad dermatitis (FPD) is a type of contact dermatitis affecting the plantar region of the feet in poultry and other birds. Hyperkeratosis and necrosis of the epidermis can develop, and in severe cases, these changes are followed by ulcerations with inflammatory reactions of the subcutaneous tissue (Ekstrand et al., 1997). The lesions are commonly named ammonia burns and are thought to be caused by a combination of moisture, high ammonia content, and other not yet specified chemical factors in the litter (Berg, 2004).Selection for rapid growth rate in broilers is accompanied by a decrease in walking ability, and there is a high unfavorable phenotypic correlation (0.8) found between BW and overall walking ability (Kestin et al., 2001). Materials and methods A total of 300 one-day-old broiler chicks of a commercial breed (Ross 308) were used. During the first week, chicks were fed cornsoybean meal starter diet. At 7 days of age chicks were allocated randomly to five treatment groups. Each treatment group consisted of four replicates each of 15 chicks. The following five treatments were employed: control (groundwheat with 50, 100 and 150 g wheat per kg respectively in starter, grower and finisher diet), sequentially two different times of access (6 and 12 h) to wet or dry whole wheat to alternate corn-soybean meal diet and also in free choice feeding of wet (FWW) or dry (FDW) whole wheat to alternate corn-soybean meal diet in separate feeders. Wet wheat were prepared fresh daily by adding 1.3 kg water to each kg of air-dry wheat. The time interval between wetting and delivery of wheat to the birds was about 15 min and wet food would therefore have an average of 12 h soaking period during each 24 h. The wheat used in the study, a soft wheat of unknown cultivar, was obtained from commercial sources, contained 110 g CP/kg as fed basis. Four birds within each pen were randomly selected as focal animals. The foot pads and hocks of the focal animals were inspected on slaughter at 6 wk (Ross 308) Feet of any other chickens that died during the week were also scored. The foot pads of both feet were scored. If the feet were dirty, they were gently washed with a wet cloth before scoring. Only the central plantar was scored. A scale from 0 (no, lesions, no or very small superficial lesions, slight discoloration on a limited area, mild thickening of the skin) to 3 (very severe lesions, ulcers or scabs, signs of haemorrhages or swollen foot pads) was used to evaluate degree of discoloration of papillae as well as the number and severity of scratches and wounds. The hocks were given 0 (not affected), 1 and 2 (color changes or minor lesions) or 3 points (severe lesions). Left and right hock were scored separately. And Subjective gait scoring was used to assess bird mobility according to Garner et al. (2002).The GS was evaluated on individual birds (4 males and 4 females per pen).birds were selected at random at 41 d of age and were weighed and wing-banded for identification purposes. The GS consists of a 4- point scale from 0 to 3, where 0 represents no detectable gait abnormality and 3 indicates a bird incapable of standing on its feet and birds tried to use their wings to aid walking, or crawled along on their shanks Gait scores were assessed on d 42. Body weights were also collected at these times to correlate BW with GS. On day 42, two birds (closest to the mean pen weight) were selected from each replicate pen, and fasted for 6 h. After fasting and the birds were slaughtered and right legs of the birds were evaluated for the establishment of scores of the Femoral degeneration (FD) and Tibial dyschondroplasia (TD).The evaluation of valgus and varus was assess the angle of the joints of the legs for this four birds within each pen were randomly selected to measure the angle between the tibia and the third finger on the right leg and left, when the angle was negative characterized the varus deformity and World s Poultry Science Journal, Supplement 1, Expanded Abstract - Poster Presentation - Poultry and Welfare Environment, 155

3 when the angle was positive, characterized the valgus deformity. On Statistical analysis all data were subjected to one-way analysis of variance using the general linear models procedure of the SAS (SAS Institute, 1997). Significant differences were considered at P<0.05. RESULTS AND DISCUSSION The effects of sequential feeding of wet and dry whole wheat on leg problems of broiler chicks are presented in Table 1 and the effects of free choice feeding of wet and dry whole wheat on leg problems of broiler chicks are presented in Table 2. Results showed the gait score was low in broilers feeding the 12 h sequential wet wholewheat maybe it is worth noting that the mean GS values did not exceed 1, regardless of the dietary nutrient density, feed form, or lighting program. This indicates that intensive selection against skeletal abnormalities has improved the skeletal condition, in agreement with industry perception and recent reports from our laboratory (Classen et al., 2003, 2004). Sorensen et al. (2000) reported that GS was increased to 2 at 49 d of age, compared with a mean GS of 0.9 at 28 d of age. The GS values may have increased had the birds been reared to an older age, and hence heavier BW, because the data in this study illustrate that GS increases with age. Tablante et al. (2003) reported that the higher growth rate of male broilers may reduce Table 1 - Effect of sequential feeding of wet and dry whole wheat on leg problems of broiler chicks (7-42 d). Variable Control SWWF SDWF 6h 12h 6h 12h Significant Body weight (g) ** TD NS GS NS FD * Food pad dermatitis ** Hock Born * Valgus/Varus * Control: ground-wheat with 50, 100 and 150 g wheat per kg respectively in starter, grower and finisher diet; SWWF: Sequential wet whole-wheat feeding; SDWF: Sequential dry whole-wheat feeding TD: Tibial dyschondroplasia, GS: walking ability, FD: femoral degeneraation, valgus/varus: leg deformities. NS: Not significant *: P<0.05 **: P<0.01 Table 2 - Effect of free choice feeding of wet and dry whole wheat on leg problems of broiler chicks (7-42 d) Variable Control FDW FWW Significant Body weight (g) ** TD NS GS NS FD NS Food pad dermatitis ** Hock Born NS Valgus/Varus NS Control: ground-wheat with 50, 100 and 150 g wheat per kg respectively in starter, grower and finisher diet; FWW: free choice feeding of wet whole-wheat feeding; FDW: free choice feeding of dry whole-wheat feeding, TD: Tibial dyschondroplasia, GS: walking ability, FD: femoral degeneration, valgus/varus: leg deformities. NS: Not significant. *: P<0.05 **: P<0.01. the bone mineral content because of incomplete or inadequate bone mineralization at 42 d of age, likely because of differences in physiology (testosterone and estrogen) and how it alters bone formation and remodeling. The higher incidence in leg abnormalities in males may be the result of poor bone mineralization; therefore, the higher bone mineral content in female broilers supports the improvement in their walking ability. Valgus/Varus deformities was low in broilers feeding the 12 h sequential dry whole-wheat (P<0.05) perhaps as for the different grades of 156, World s Poultry Science Journal, Supplement 1, Expanded Abstract - Poster Presentation - Poultry and Welfare Environment

4 GS was found significant difference for legs, the largest deviation of joint-related GS 3 (bird with difficulty walking) indicating that this deformity may be related to these characteristics (age and GS). Santora et al. (2001) also found a positive correlation between GS and Valgus/ Varus deformity. Also results showed the Broilers received dry whole wheat sequential feeding for 6 and 12 h had the lowest foot pad dermatitis (P<0.01). Diet affects the incidence of foot pad dermatitis but there is evidence to suggest that it plays a key role. Methionine is an important amino acid for poultry and helps with skin healing, so a diet low in methionine may lead to higher levels of foot pad dermatitis. In addition, if the diet is not especially formulated to balance the essential amino acids that the birds require, then it may be overloaded with crude protein. Some feed mills simply add bulk protein on the assumption that the birds will be able to get what they need from it. However, this overloading can lead to the birds excreting excess nitrogen and loose, sticky droppings, which can make it harder to keep bedding dry and stick to the bird s feet making them even more prone to foot pad dermatitis.results showed the Broilers received dry whole wheat sequential wet whole-wheat feeding had for 12 h had the lowest femoral degeneration in comparison with other treatment (P<0.05). Tibial dyschondroplasia was not affected significantly by dietary treatments. Hock born dermatitis decrease in broilers received free choice feeding of dry whole-wheat feeding and sequential dry whole-wheat feeding for 6 h. REFERENCES ALMEIDA PAZ, I.C.L., MENDES, A.A., MARTINS, M.R.F.B., FERNANDES, B. C. S., ALMEIDA, I.C.L., MILBRADT, E.L., BALOG, A. and KOMIYAMA, C.M. (2009) Follow-up of the development of femoral degeneration lesions in broilers. Int. J. Morphol. 27(2): AMERAH, A.M., RAVINDRAN V. (2008) Influence of method of whole-wheat feeding on the performance, carcass traits and digestive tract development of broiler chickens. Animal Feed Science and Technology 147(4): BERG, C. (2004) Pododermatitis and hock burn in broiler chickens. Page 37 in Measuring and Auditing Broiler Welfare. C. A. Weeks and A. Butterworth, ed. CABI Publishing, Wallingford, UK. EKSTRAND, C., ALGERS, B., and J. SVEDBERG. (1997) Rearing conditions and foot pad dermatitis in Swedish broiler chickens. Prev. Vet. Med. 31: GARNER, J. P., FALCONE, C., WAKENELL, P., MARTIN, M. and MENCH, J.A. (2002) Reliability and validity of a modified gait scoring system and its use in assessing tibial dyschondroplasia in broilers. Br. Poult. Sci. 43: HALL, A.L. (2001) The effect of stocking density on the welfare and behaviour of broiler chickens reared commercially. Animal Welfare 10: HUNTER, B., WHITEMAN, A,. SANEI B. and DAM, A. (2008) Valgus/Varus Leg Deformities in Poultry Factsheet KESTIN, S.C., GORDON, S., SU., G. and SORENSEN, P. (2001) Relationship in broiler between lameness, liveweight, growth rate and age. Vet. Rec. 148: KJAER, J.B., SU, G., NIELSEN, B.L. and SORENSEN, P. (2006) Foot Pad Dermatitis and Hock Burn in Broiler Chickens and Degree of Inheritance. Poultry Science 85: MCGEOWN, D., DANBURY, T.C., WATERMAN-PEARSON, A.E. and KESTIN, S.C. (1999) Effect of carprofen on lameness in broiler chickens. Vet. Rec. 144: ROSE, S.P., FIELDEN, M., FOOTE, W.R. and GARDIN, P. (1995) Sequential feeding of whole wheat to growing broiler chickens. British Poultry Science 36(1): SANOTRA, G.S., LUND, J.D., ERSBOLL, A.K., PETERSEN, J.S. and VESTERGAARD, K.S. (2001) Monitoring leg problems in broilers: A survey of commercial broiler production in Denmark. World s Poult. Sci. J. 57: SCAHAW.( 2000) The welfare of chickens kept for meat production (broilers). Report of the Scientific Committee on Animal Health World s Poultry Science Journal, Supplement 1, Expanded Abstract - Poster Presentation - Poultry and Welfare Environment, 157

5 and Animal Welfare. Adopted 21 March Brussels, European Commission. SORENSEN, P., SU, G. and KESTIN, S.C. (2000) Effects of age and stocking density on leg weakness in broiler chickens. Poult. Sci. 79: TABLANTE, N.L., ESTEVEZ, I. and RUSSEK- COHEN, E. (2003) Effect of perches and stocking density on tibial dyschondroplasia and bone mineralization as measured by bone ash in broiler chickens. J. Appl. Poult. Res. 12: , World s Poultry Science Journal, Supplement 1, Expanded Abstract - Poster Presentation - Poultry and Welfare Environment