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The gizzard: function, influence of diet structure and effects on nutrient availability

Published online by Cambridge University Press:  20 June 2011

B. SVIHUS*
Affiliation:
Department of Animal and Aquacultural Sciences, Norwegian University of Life Sciences, PO Box 5003, N-1432 Aas, Norway
*
Corresponding author: [email protected]
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Abstract

The gizzard has a number of important functions, such as aiding digestion by particle size reduction, chemical degradation of nutrients and regulation of feed flow, and responds rapidly to changes in the coarseness of the diet. This review summarises findings on the function of the gizzard, the interaction between diet and gizzard function, and the nutritional consequences of these interactions. Due to the reported improvements in nutrient availability when structural components which stimulate gizzard development has been added to the diet, it may be recommended to include at least 20 to 30% cereal particles larger than 1 mm in size, or to include at least 3% coarse fibres such as oat hulls, in the diet.

Type
Review Article
Copyright
Copyright © World's Poultry Science Association 2011

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References

AKESTER, A.R. (1986) Structure of the glandular layer and koilin membrane in the gizzard of the adult domestic fowl (Gallus gallus domesticus). Journal of Anatomy 147: 1-25.Google ScholarPubMed
ALMIRALL, M. and ESTEVE-GARCIA, E. (1995) In vitro stability of a β-glucanase preparation from Trichoderma longibrachiatum and its effect in a barley based diet fed to broiler chicks. Animal Feed Science and Technology 54: 149-158.CrossRefGoogle Scholar
AMERAH, A.M. and RAVINDRAN, V. (2008) Influence of method of whole-wheat feeding on the performance, digestive tract development and carcass traits of broiler chickens. Animal Feed Science and Technology 147: 326-339.CrossRefGoogle Scholar
AMERAH, A.M., RAVINDRAN, V. and LENTLE, R.G. (2009a) Influence of wheat hardness and xylanase supplementation on the performance, energy utilisation, digestive tract development and digesta parameters of broiler starters. Animal Production Science 49: 71-78.CrossRefGoogle Scholar
AMERAH, A.M., RAVINDRAN, V. and LENTLE, R.G. (2009b) Influence of insoluble fibre and whole wheat inclusion on the performance, digestive tract development and ileal microbiota profile of broiler chickens. British Poultry Science 50: 366-375.CrossRefGoogle ScholarPubMed
AMERAH, A.M., RAVINDRAN, V., LENTLE, R.G. and THOMAS, D.G. (2008) Influence of feed particle size on the performance, energy utilisation, digestive tract development, and digesta parameters of broiler starters fed wheat- and corn-based diets. Poultry Science 87: 2320-2328.CrossRefGoogle ScholarPubMed
ANDRYS, R., KLECKER, D., ZEMAN, L. and MARECEK, E. (2003) The effect of changed pH values of feed in isophosphoric diets on chicken broiler performance. Czech Journal of Animal Science 48: 197-206.Google Scholar
AO, T., CANTOR, A.H., PESCATORE, A.J. and PIERCE, J.L. (2008) In vitro evaluation of feed-grade enzyme activity at pH levels simulating various parts of the avian digestive tract. Animal Feed Science and Technology 140: 462-468.CrossRefGoogle Scholar
BALLOUN, S.L. and PHILLIPS, R.E. (1956) Grit feeding affects growth and feed utilization of chicks and egg production of laying hens. Poultry Science 35: 566-569.CrossRefGoogle Scholar
BANFIELD, M.J. and FORBES, J.M. (2001) Effects of whole wheat dilution v. substitution on coccidiosis in broiler chickens. British Journal of Nutrition 86: 89-95.Google Scholar
BEAUNE, D., LE BOHEC, C., LUCAS, F., GAUTHIER-CLERC, M. and LE MAHO, Y. (2009) Stomach stones in king penguin chicks. Polar Biology 32: 593-597.Google Scholar
BENNETT, C.D. and CLASSEN, H.L. (2003) Performance of two strains of laying hens fed ground and whole barley with and without access to insoluble grit. Poultry Science 82: 147-149.CrossRefGoogle ScholarPubMed
BENNETT, C.D., CLASSEN, H.L. and RIDDELL, C. (1995) Live performance and health of broiler chickens fed diets diluted with whole or crumbled wheat. Canadian Journal of Animal Science 75: 611-614.CrossRefGoogle Scholar
BENNETT, C.D., CLASSEN, H.L. and RIDDELL, C. (2002) Feeding broiler chickens wheat and barley diets containing whole, ground and pelleted grain. Canadian Journal of Animal Science 75: 611-614.Google Scholar
BIGGS, P. and PARSONS, C.M. (2009) The effects of whole grains on nutrient digestibilities, growth performance, and cecal short-chain fatty acid concentrations in young chicks fed ground corn-soybean meal diets. Poultry Science 88: 1893-1905.Google Scholar
BJERRUM, L., PEDERSEN, K. and ENGBERG, R.M. (2005) The influence of whole wheat feeding on salmonella infection and gut flora composition in broilers. Avian Diseases 49: 9-15.CrossRefGoogle ScholarPubMed
BOLTON, W. (1965) Digestion in the crop of the fowl. British Poultry Science 6: 97-102.CrossRefGoogle ScholarPubMed
BOROS, D., MARQUARDT, R.R. and GUENTER, W. (1998) Site of exoenzyme action in gastrointestinal tract of broiler chickens. Canadian Journal of Animal Science 78: 599-602.Google Scholar
CARLSON, D. and POULSEN, H.D. (2003) Phytate degradation in soaked and fermented liquid feed - effect of diet, time of soaking, heat treatment, phytase activity, pH and temperature. Animal Feed Science and Technology 103: 141-154.CrossRefGoogle Scholar
CHAPLIN, S.B., RAVEN, J. and DUKE, G.E. (1992) The influence of the stomach on crop function and feeding behaviour in domestic turkeys. Physiology and Behavior 52: 261-266.Google Scholar
CLARK, P.M., BEHNKE, K.C. and FAHRENHOLZ, A.C. (2009) Effects of feeding cracked corn and concentrate protein pellets on broiler growth performance. Journal of Applied Poultry Research 18: 259-268.CrossRefGoogle Scholar
CLEMENS, E.T., STEVENS, C.E. and SOUTHWORTH, M. (1975) Sites of organic acid production and pattern of digesta movement in the gastrointestinal tract of geese. Journal of Nutrition 105: 1341-1350.Google Scholar
CLINE, M.A., NANDAR, W., BOWDEN, C., CALCHARY, W., SMITH, M.L., PRALL, B., NEWMYER, B., ROGERS, J.O. and SIEGEL, P.B. (2010) The threshold of amylin-induced anorexia is lower in chicks selected for low compared to high juvenile body weight. Behavioural Brain Research 208: 650-654.Google Scholar
DÄNICKE, S., VAHJEN, W., SIMON, O. and JEROCH, H. (1999) Effects of dietary fat type and xylanase supplementation to rye-based broiler diets on selected bacterial groups adhering to the intestinal epithelium, on transit time of feed, and on nutrient digestibility. Poultry Science 78: 1292-1299.Google Scholar
DENBOW, D.M. (1994) Peripheral regulation of food intake in poultry. Journal of Nutrition 124: 1349S-1354S.CrossRefGoogle ScholarPubMed
DENBOW, D.M. (2000) Gastrointestinal anatomy and physiology, in: WHITTOW, G.C. (Ed.) Sturkie's avian physiology, pp. 299-325 (New York, Academic Press).Google Scholar
DENSTADLI, V., BALLANCE, S., KNUTSEN, S.H., WESTERENG, B. and SVIHUS, B. (2010) Influence of graded levels of brewers' dried grain on pellet quality, performance and gut function in broiler chickens. Poultry Science 89: 2640-2645.CrossRefGoogle Scholar
DORMITORIO, T.V., GIAMBRONE, J.J. and HOERR, E.J. (2007) Transmissible proventriculitis in broilers. Avian Pathology 36: 87-91.CrossRefGoogle ScholarPubMed
DUKE, G.E. (1986) Alimentary canal: secretion and digestion, special digestive functions, and absorption, in: STURKIE, P.D. (Ed.) Avian Physiology, pp. 289-302 (New York, Springer-Verlag).Google Scholar
DUKE, G.E. (1992) Recent studies on regulation of gastric motility in turkeys. Poultry Science 71: 1-8.CrossRefGoogle ScholarPubMed
ENGBERG, R.M., HEDEMANN, M.S. and JENSEN, B.B. (2002) The influence of grinding and pelleting of feed on the microbial composition and activity in the digestive tract of broiler chickens. British Poultry Science 43: 569-579.CrossRefGoogle ScholarPubMed
ENGBERG, R.M., HEDEMANN, M.S., STEENFELDT, S. and JENSEN, B.B. (2004) Influence of Whole Wheat and Xylanase on Broiler Performance and Microbial Composition and Activity in the Digestive Tract. Poultry Science 83: 925-938.CrossRefGoogle ScholarPubMed
EWING, W.R. (1951) Poultry nutrition, fourth edition (Pasadena, USA, W. Ray Ewing publisher).Google Scholar
FARNER, D.S. (1960) Digestion and the digestive system, in: MARSHALL, A.J. (Ed.) Biology and comparative physiology of birds, pp. 411-467 (New York, Academic Press).Google Scholar
FERRANDO, C., VERGARA, P., JIMÉNEZ, M. and GOÑALONS, E. (1987) Study of the rate of passage of food with chromium-mordanted plant cells in chickens (Gallus gallus). Quarterly Journal of Experimental Physiology 72: 251-259.CrossRefGoogle ScholarPubMed
FRIKHA, M., SAFAA, H.M., SERRANO, M.P., ARBE, X. and MATEOS, G.G. (2009) Influence of the main cereal and feed form of the diet on performance and digestive tract traits of brown-egg laying pullets. Poultry Science 88: 994-1002.CrossRefGoogle ScholarPubMed
GABRIEL, I., MALLET, S. and LECONTE, M. (2003) Differences in the digestive tract characteristics of broiler chickens fed on complete pelleted diet or on whole wheat added to pelleted protein concentrate. British Poultry Science 44: 283-290.CrossRefGoogle ScholarPubMed
GABRIEL, I., MALLET, S., LECONTE, M., TRAVEL, A. and LALLES, J.P. (2008) Effects of whole wheat feeding on the development of the digestive tract of broiler chickens. Animal Feed Science and Technology 142: 144-162.Google Scholar
GARIPOGLU, A.V, ERENER, G. and OCAK, N. (2006) Voluntary intake of insoluble granite-grit offered in free choice by broilers: Its effect on their digestive tract traits and performances. Asian-Australian Journal of Animal Science 19: 549-553.CrossRefGoogle Scholar
GIONFRIDDO, J.P. and BEST, L.B. (1996) Grit-use patterns in North American birds: The influence of diet, body size, and gender. Wilson Bulletin 108: 685-696.Google Scholar
GONZALES-ALVARADO, J.M., JIMENEZ-MORENO, E., VALENCIA, D.G., LAZARO, R. and MATEOS, G.G. (2008) Effects of fiber source and heat processing of the cereal on the development and pH of the gastrointestinal tract of broilers fed diets based on corn or rice. Poultry Science 87: 1779-1795.Google Scholar
GONZALES-ALVARADO, J.M., JIMENEZ-MORENO, E., VALENCIA, D.G., LAZARO, R. and MATEOS, G.G. (2007) Effects of type of cereal, heat processing of the cereal, and inclusion of fiber in the diet on productive performance and digestive traits of broilers. Poultry Science 86: 1705-1715.Google Scholar
GORDON, R.W. and ROLAND, D.A. (1997) The influence of environmental temperature on in vivo limestone solubilization, feed passage rate, and gastrointestinal pH in laying hens. Poultry Science 76: 683-688.Google Scholar
GUINOTTE, F. and NYS, Y. (1991) Effects of particle size and origin of calcium sources on eggshell quality and bone mineralization in egg laying hens. Poultry Science 70: 583-592.Google Scholar
GUINOTTE, F., GAUTRON, J., NYS, Y. and SOUMARMON, A. (1995) Calcium solubilisation and retention in the gastrointestinal tract in chicks (Gallus domesticus) as a function of gastric acid secretion inhibition and calcium carbonate particle size. British Journal of Nutrition 73: 125-139.Google Scholar
HAVENSTEIN, G.B., FERKET, P.R. and QURESHI, M.A. (2003) Growth, livability, and feed conversion of 1957 versus 2001 broilers when fed representative 1957 and 2001 broiler diets. Poultry Science 82: 1500-1508.Google Scholar
HETLAND, H. and SVIHUS, B. (2001) Effect of oat hulls on performance, gut capacity and feed passage time in broiler chickens. British Poultry Science 42: 354-361.CrossRefGoogle ScholarPubMed
HETLAND, H. and SVIHUS, B. (2007) Inclusion of dust bathing materials affects nutrient digestion and gut physiology of layers. Journal of Applied Poultry Research 16: 22-26.Google Scholar
HETLAND, H., SVIHUS, B. and CHOCT, M. (2005) Role of insoluble fiber on gizzard activity in layers. Journal of Applied Poultry Research 14: 38-46.CrossRefGoogle Scholar
HETLAND, H., SVIHUS, B., KROGDAHL, and Å., (2003) Effects of oat hulls and wood shavings on digestion in broilers and layers fed diets based on whole or ground wheat. British Poultry Science 44: 275-282.CrossRefGoogle ScholarPubMed
HETLAND, H., SVIHUS, B. and OLAISEN, V. (2002) Effect of feeding whole cereals on performance, starch digestibility and duodenal particle size distribution in broiler chickens. British Poultry Science 43: 416-423.Google Scholar
HILL, K.J. (1971) The structure of the alimentary tract, in: BELL, D.J. & FREEMAN, B.M. (Eds), Physiology and biochemistry of the domestic fowl, Vol. 1, pp. 1-23 (London, Academic press).Google Scholar
HOCKING, P.M. (2006) High-fibre pelleted rations decrease water intake but do not improve physiological indexes of welfare in food-restricted female broiler breeders. British Poultry Science 47: 19-23.Google Scholar
HUANG, D.S., LI, D.F., XING, J.J., MA, Y.X., LI, Z.J. and LV, S.Q. (2006) Effects of feed particle size and feed form on survival of Salmonella typhimurium in the alimentary tract and cecal S. typhimurium reduction in growing broilers. Poultry Science 85: 831-836.CrossRefGoogle ScholarPubMed
IBRAHIM, M.A. and EL ZUBEIR, E.A. (1991) Higher fibre sunflower seed meal in broiler chick diets. Animal Feed Science and Technology 33: 343-347.Google Scholar
JACKSON, S. and DUKE, G.E. (1995) Intestine fullness influences feeding behaviour and crop filling in the domestic turkey. Physiology and Behavior 58: 1027-1034.CrossRefGoogle ScholarPubMed
JIMENEZ-MORENO, E., GONZALEZ-ALVARADO, J.M., LAZARO, R. and MATEOS, G.G. (2009) Effects of type of cereal, heat processing of the cereal, and fiber inclusion in the diet on gizzard pH and nutrient utilization in broilers at different ages. Poultry Science 88: 1925-1933.CrossRefGoogle ScholarPubMed
JONES, G.P.D. and TAYLOR, R.D. (2001) The incorporation of whole grain into pelleted broiler chicken diets: production and physiological responses. British Poultry Science 42: 477-483.CrossRefGoogle ScholarPubMed
JOZEFIAK, D., RUTKOWSKI, A., JENSEN, B.B. and ENGBERG, R.M. (2007) Effects of dietary inclusion of triticale, rye and wheat and xylanase supplementation on growth performance of broiler chickens and fermentation in the gastrointestinal tract. Animal Feed Science and Technology 132: 79-93.Google Scholar
KA, S., LINDBERG, J., STROMSTEDT, L., FITZSIMMONS, C., LINDQVIST, N., LUNDEBERG, J., SIEGEL, P.B., ANDERSSON, L. and HALLBOOK, F. (2009) Extremely Different Behaviours in High and Low Body Weight Lines of Chicken are Associated with Differential Expression of Genes Involved in Neuronal Plasticity. Journal of Neuroendocrinology 21: 208-216.CrossRefGoogle ScholarPubMed
KLASING, K.C. (1998) Comparative avian nutrition. (Wallingford, UK, CAB International).CrossRefGoogle Scholar
KLASING, K.C. (2005) Poultry nutrition: A comparative approach. Journal of Applied Poultry Research 14: 426-436.CrossRefGoogle Scholar
KOCH, M., PÄRSCHKE, S. and EDGECOMBE, G.D. (2009) Phylogenetic implications of gizzard morphology in scolopendromorph centipedes (Chilopoda). Zoologica Scripta 38: 269-288.Google Scholar
LEESON, S., CASTON, L. and SUMMERS, J.D. (1996) Broiler response to energy or energy and protein dilution in the finisher diet. Poultry Science 75: 522-528.CrossRefGoogle ScholarPubMed
LI, Y. and OWYANG, C. (1993) Vagal afferent pathway mediates physiological action of cholecystokinin on pancreatic-enzyme secretion. Journal of Clinical Investigation 92: 418-424.Google Scholar
MAHAGNA, M. and NIR, I. (1996) Comparative development of digestive organs, intestinal disaccharidases and some blood metabolites in broiler and layer-type chicks after hatching. British Poultry Science 37: 359-371.Google Scholar
MAHAGNA, M., NIR, I., LARBIER, M. and NITSAN, Z. (1995) Effect of age and exogenous amylase and protease on development of the digestive tract, pancreatic enzyme activities and digestibility of nutrients in young meat-type chicks. Reproduction and Nutrition Development 35: 201-212.CrossRefGoogle ScholarPubMed
MALONE, G.W., CHALOUPKA, G.W. and SAYLOR, W.W. (1983) Influence of litter type and size on broiler performance. 1. Factors affecting litter consumption. Poultry Science 62: 1741-1746.Google Scholar
MCLELLAND, J. (1979) Digestive system, in: KING, A.S. & MCLELLAND, J. (Eds) Form and function in birds, pp. 69-182 (London, Academic Press).Google Scholar
MOORE, S.J. (1999) Food breakdown in an avian herbivore; who needs teeth? Australian Journal of Zoology 47: 625-632.CrossRefGoogle Scholar
MURAI, A., SATOH, S., OKUMURA, J.-I. and FURUSE, M. (2000) Factors regulating secretion from chicken pancreatic acini in vitro. Life Science 66: 585-591.Google Scholar
NAHAS, J. and LEFRANCOIS, M.R. (2001) Effects of feeding locally grown whole barley with or without enzyme addition and whole wheat on broiler performance and carcass traits. Poultry Science 80: 195-202.CrossRefGoogle ScholarPubMed
NIR, I., HILLEL, R., SHEFET, G. and NITSAN, Z. (1994) Effect of grain particle size on performance. 2. Grain texture interactions. Poultry Science 73: 781-791.Google Scholar
NORRIS, E., NORRIS, C. and STEEN, J.B. (1975) Regulation and grinding ability of grit in the gizzard of Norwegian willow ptarmigan ( Lagopus lagopus). Poultry Science 54: 1839-1843.CrossRefGoogle ScholarPubMed
O'DELL, B.L., NEWBERNE, P.M. and SAVAGE, J.E. (1959) An abnormality of the proventriculus caused by feed texture. Poultry Science 38: 296-301.Google Scholar
O'SULLIVAN, N.P., DUNNINGTON, E.A. and SIEGEL, P.B. (1992) Correlated responses in lines of chickens divergently selected for fifty-six-day body weight. 1. Growth, feed intake, and feed utilization . Poultry Science 71: 590-597.Google Scholar
PANIGRAHI., S. and POWELL, C.J. (1991) Effects of high rates of inclusion of palm kernel meal in broiler chick diets. Animal Feed Science and Technology 34: 37-47.Google Scholar
PARSONS, A.S., BUCHANAN, N.P., BLEMINGS, K.P., WILSON, M.E. and MORITZ, J.S. (2006) Effect of corn particle size and pellet texture on broiler performance in the growing phase. Journal of Applied Poultry Research 15: 245-255.CrossRefGoogle Scholar
PARTANEN, K., JALAVA, T. and VALAJA, J. (2007) Effects of a dietary organic acid mixture and of dietary fibre levels on ileal and faecal nutrient apparent digestibility, bacterial nitrogen flow, microbial metabolite concentrations and rate of passage in the digestive tract of pigs. Animal 1: 389-401.Google Scholar
PÉRON, A., BASTIANELLI, D., OURY, F.-X., GOMEZ, J. and CARRÉ, B. (2005) Effects of food deprivation and particle size of ground wheat on digestibility of food components in broilers fed on a pelleted diet. British Poultry Science 46: 223-230.CrossRefGoogle ScholarPubMed
PÉRON, A., SVIHUS, B., GABRIEL, I., BÉROT, S., TANGUY, D., BOUCHET, B., GOMEZ, J. and CARRÉ, B. (2007) Effects of two wheat cultivars on physico-chemical properties of wheat flours and digesta from two broiler chicken lines (D+ and D-) differing in digestion capacity. British Poultry Science 48: 370-380.Google Scholar
PLAVNIK, I., MACOVSKY, B. and SKLAN, D. (2002) Effect of feeding whole wheat on performance of broiler chickens. Animal Feed Science and Technology 96: 229-236.Google Scholar
PRESTON, C.M., MCCRACKEN, K.J. and MCALLISTER, A. (2000) Effect of diet form and enzyme supplementation on growth, efficiency and energy utilisation of wheat-based diets for broilers. British Poultry Science 41: 324-331.Google Scholar
RAVINDRAN, V., WU, Y.B., THOMAS, D.G. and MOREL, P.C.H. (2006) Influence of whole wheat feeding on the development of gastrointestinal tract and performance of broiler chickens. Australian Journal of Agricultural Research 57: 21-26.Google Scholar
RICHARDS, M.P. and PROSZKOWIEC-WEGLARZ, M. (2007) Mechanisms regulating feed intake, energy Expenditure, and body weight in poultry. Poultry Science 86: 1478-1490.CrossRefGoogle ScholarPubMed
RILEY, W.W. JR. and AUSTIC, R.E. (1984) Influence of dietary electrolytes on digestive tract pH and acid-base status of chicks. Poultry Science 63: 2247-2251.Google Scholar
RODGERS, N. (2008) Altering broiler gut development, morphology, microbiology and function by manipulating feed grain type, particle size and milling method affects life-long performance. Ph. D. Thesis, University of New England, Australia.Google Scholar
ROGEL, A.M., ANNISON, E.F., BRYDEN, W.L. and BALNAVE, D. (1987) . The digestion of wheat starch in broiler chickens. Australian Journal of Agricultural Research 38: 639-649.CrossRefGoogle Scholar
ROUGIERE, N., GOMEZ, J., MIGNON-GRASTEAU, S. and CARRÉ, B. (2009) Effects of diet particle size on digestive parameters in D+ and D- genetic chicken lines selected for divergent digestion efficiency. Poultry Science 88: 1206-1215.Google Scholar
SACRANIE, A. (2010) How feed constituents regulate gut motility, feed utilisation and growth in broiler chickens. Ph. D. Thesis, University of New England, Australia.Google Scholar
SANTOS, F.B.O., SHELDON, B.W., SANTOS, A.A. JR. and FERKET, P.R. (2008) Influence of housing system, grain type, and particle size on Salmonella colonization and shedding of broilers fed triticale or corn-soybean meal diets. Poultry Science 87: 405-420.Google Scholar
SCHMITZ, E.H. and BAKER, C.D. (1969) Digestive anatomy of the Gizzard Shad, Dorosoma cepedianum, and the Threadfin Shad, D. petenense. Transactions of the American Microscopical Society 88: 525-546.CrossRefGoogle Scholar
SCOTT, M.L. and HEUSER, G.F. (1957) The value of grit for chickens and turkeys. Poultry Science 36: 276-283.Google Scholar
SENKOYLU, N., SAMLI, H.E., AKYUREK, H., OKUR, A.A. and KANTER, M. (2009) Effects of whole wheat with or without xylanase supplementation on performance of layers and digestive organ development. Italian Journal of Animal Science 8: 155-163.CrossRefGoogle Scholar
SHAKOURI, M.D., IJI, P.A., MIKKELSEN, L.L. and COWIESON, A.J. (2009) Intestinal function and gut microflora of broiler chickens as influenced by cereal grains and microbial enzyme supplementation. Animal Physiology and animal nutrition 93: 647-658.CrossRefGoogle ScholarPubMed
SHIRES, A., THOMPSON, J.R., TURNER, B.V., KENNEDY, P.M. and GOH, Y.K. (1987) Rate of passage of canola meal and corn-soybean meal diets through the gastrointestinal tract of broiler and white leghorn chickens. Poultry Science 66: 289-298.Google Scholar
SIEGEL, P.B. and DUNNINGTON, E.A. (1987) Selection for growth in chickens. CRC Critical Reviews of Poultry Biology 1: 1-24.Google Scholar
SIEGEL, P.B., CHERRY, J.A. and DUNNINGTON, E.A. (1984) Feeding behaviour and feed consumption in chickens selected for body weight. Annales Agriculturae Fenniae 23: 247-252.Google Scholar
SMULIKOWSKA, S., CZERWINSKI, J., MIECZKOWSKA, A. and JANKOWIAK, J. (2009) The effect of fat-coated organic salts and a feed enzyme on growth performance nutrient utilization, microflora activity, and morphology of the small intestine in broiler chickens. Journal of Animal and Feed Sciences 18: 478-489.Google Scholar
STARCK, J.M. (1999) Phenotypic flexibility of the avian gizzard: rapid, reversible and repeated changes of organ size in response to changes in dietary fibre content. The Journal of Experimental Biology 202: 3171-3179.Google Scholar
STEENFELDT, S. (2001) The dietary effect of different wheat cultivars for broiler chickens. British Poultry Science 42: 595-609.CrossRefGoogle ScholarPubMed
STEENFELDT, S., KJAER, J.B. and ENGBERG, R.M. (2007) Effect of feeding silages or carrots as supplements to laying hens on production performance, nutrient digestibility, gut structure, gut microflora and feather pecking behaviour. British Poultry Science 48: 454-468.CrossRefGoogle ScholarPubMed
SVIHUS, B. (2006) The role of feed processing on gastrointestinal function and health in poultry, in: PERRY, G.C. (Ed.) Avian gut function in health and disease, Poultry Science Symposium Series vol. 28, (Oxfordshire, UK, CABI publishing).Google Scholar
SVIHUS, B., HERSTAD, O., NEWMAN, C.W. and NEWMAN, R.K. (1997) Comparison of performance and intestinal characteristics of broiler chickens fed on diets containing whole, rolled or ground barley. British Poultry Science 38: 524-529.Google Scholar
SVIHUS, B. and HETLAND, H. (2001) Ileal starch digestibility in growing broiler chickens fed on a wheat based diet is improved by mash feeding, dilution with cellulose or whole wheat inclusion. British Poultry Science 42: 633-637.CrossRefGoogle ScholarPubMed
SVIHUS, B., JUVIK, E., HETLAND, H. and KROGDAHL, A. (2004a) Causes for improvement in nutritive value of broiler chicken diets with whole wheat instead of ground wheat. British Poultry Science 45: 55-60.Google Scholar
SVIHUS, B., HETLAND, H., CHOCT, M. and SUNDBY, F. (2002) Passage rate through the anterior digestive tract of broiler chickens fed on diets with ground or whole wheat. British Poultry Science 43: 662-668.Google Scholar
SVIHUS, B., KLØVSTAD, K.H., PEREZ, V., ZIMONJA, O., SAHLSTRÖM, S., SCHULLER, R.B., JEKSRUD, W.K. and PRESTLØKKEN, E. (2004b) Physical and nutritional effects of pelleting of broiler chicken diets made from wheat ground to different coarsenesses by the use of roller mill and hammer mill. Animal Feed Science and Technology 117: 281-293.Google Scholar
SVIHUS, S., SACRANIE, A., DENSTADLI, V. and CHOCT, M. (2010) Nutrient utilization and functionality of the anterior digestive tract due to intermittent feeding and whole wheat inclusion in diets for broiler chickens. Poultry Science 89: 2617-2625.Google Scholar
UDDIN, M.S., ROSE, S.P., HISCOCK, T.A. and BONNET, S. (1996) A comparison of the energy availability for chickens of ground and whole grain samples of two wheat varieties. British Poultry Science 37: 347-357.Google Scholar
VAHJEN, W. and SIMON, O. (1999) Biochemical characteristics of non starch polysaccharide hydrolyzing enzyme preparations designed as feed additives for poultry and piglet nutrition. Archives of Animal Nutrition 52: 1-14.Google Scholar
VAN DER KLIS, J.D., VERSTEGEN, M.W.A. and DE WIT, W. (1990) Absorption of minerals and retention time of dry matter in the gastrointestinal tract of broilers. Poultry Science 69: 2185-2194.Google Scholar
WALDENSTEDT, L., ELWINGER, K., HOOSHMAND-RAD, P., THEBO, P. and UGGLA, A. (1998) Comparison between effects of standard feed and whole wheat supplemented diet on experimental Eimeria tenella and Eimeria maxima infections in broiler chickens. Acta Veterinaera Scandinavica 39: 461-471.Google Scholar
WILLIAMS, J., MALLET, S., LECONTE, M., LESSIRE, M. and GABRIEL, I. (2008) The effects of fructo-oligosaccharides or whole wheat on the performance and digestive tract of broiler chickens. British Poultry Science 49: 329-339.Google Scholar
WU, Y.B. and RAVINDRAN, V. (2004) Influence of whole wheat inclusion and xylanase supplementation on the performance, digestive tract measurements and carcass characteristics of broiler chickens. Animal Feed Science and Technology 116: 129-139.CrossRefGoogle Scholar
WU, Y.B., RAVINDRAN, V., THOMAS, D.G., BIRTLES, M.J. and HENDRIKS, W.H. (2004) Influence of method of whole wheat inclusion and xylanase supplementation on the performance, apparent metabolisable energy, digestive tract measurements and gut morphology of broilers. British Poultry Science 45: 385-394.Google Scholar
YI, Z. and KORNEGAY, E.T. (1996) Sites of phytase activity in the gastrointestinal tract of young pigs. Animal Feed Science and Technology 61: 361-368.Google Scholar
ZHANG, B. and COON, C.N. (1997) The relationship of calcium intake, source, size, solubility in vitro and in vivo, and gizzard limestone retention in laying hens. Poultry Science 76: 1702-1706.Google Scholar