title: Nutritional value of raw and micronised field beans (Vicia faba L. var. minor) with and without enzyme supplementation containing tannase for growing chickens.
abstract: An experiment examined the effects of two field bean cultivar samples with different tannin contents, the effect of heat treatment (micronising) and the effect of dietary supplementation of a proprietary enzyme preparation containing tannase, pectinase, and xylanase activities on metabolisable energy (ME), total tract dry matter digestibility (DMD) and ether extract digestibility (EED), nitrogen retention (NR), tannin degradability, gastrointestinal tract (GIT) development, and endogenous mucin losses excretion in broiler chickens. The Control diet contained per kg 221 g crude protein and 12.83 MJ ME. Four additional diets contained 300 g/kg of each of the two untreated or micronised experimental field bean cultivar samples. Each diet was then split into two batches and one of them was supplemented with 3400 units tannase per kg diet resulting in 10 diets in total. Each diet was fed to seven pens with two randomly selected male broilers each. Birds fed the high tannin bean sample had a lower weight gain (p < 0.001), and a lower determined apparent ME (p < 0.05), and DMD (p < 0.001) but a higher tannin degradability (p < 0.001). Compared to the Control diet, feeding field beans increased (p < 0.001) the weights of the proventriculus and gizzard of the birds, and also increased endogenous mucin losses (p < 0.05). Supplementing diets with the tannase-containing enzyme preparation improved dietary ME (p < 0.001), DMD (p < 0.001), NR (p < 0.001) and DEE (p < 0.05), but did not change tannin degradability. Heat treatment of the beans reduced the degradability of condensed tannins and increased endogenous mucin losses (p < 0.05). The differences in the feeding value of the different field bean samples were not improved by heat treatment, but enzyme supplementation improved the feeding value of all diets regardless of the bean samples or heat treatment. Further research is warranted to study the effectiveness of tannase supplementation in poultry diet formulations by dose response trials with purified tannase preparations.
authors: a Department of Animal Production , Welfare and Veterinary Sciences, Harper Adams University , Newport , Shropshire , UK.|b National Institute of Poultry Husbandry , Harper Adams University , Newport , Shropshire , UK.
authors: Jalil Mahmwd
authors: JM
authors: Abdulla
authors: a Department of Animal Production , Welfare and Veterinary Sciences, Harper Adams University , Newport , Shropshire , UK.|b National Institute of Poultry Husbandry , Harper Adams University , Newport , Shropshire , UK.
authors: Stephen Paul
authors: SP
authors: Rose
authors: a Department of Animal Production , Welfare and Veterinary Sciences, Harper Adams University , Newport , Shropshire , UK.
authors: Alexander Mackay
authors: AM
authors: Mackenzie
authors: c Department of Animal Nutrition and Technology , Agricultural Institute , Shumen , Bulgaria.
authors: Sonya Georgieva
authors: SG
authors: Ivanova
authors: d Department of Genetics and Selection , Agricultural Institute , Shumen , Bulgaria.
authors: Genoveva Petrova
authors: GP
authors: Staykova
authors: a Department of Animal Production , Welfare and Veterinary Sciences, Harper Adams University , Newport , Shropshire , UK.|b National Institute of Poultry Husbandry , Harper Adams University , Newport , Shropshire , UK.
authors: Vasil Radoslavov
authors: VR
authors: Pirgozliev
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000824:Animal Nutritional Physiological Phenomena / Q000187:drug effects; D000818:Animals; D030161:Avian Proteins / Q000378:metabolism; D002265:Carboxylic Ester Hydrolases / Q000008:administration & dosage*; D002645:Chickens / Q000254:growth & development / Q000378:metabolism*; D004032:Diet / Q000662:veterinary; D019587:Dietary Supplements / Q000032:analysis; D043364:Endo-1,4-beta Xylanases / Q000378:metabolism; D004734:Energy Metabolism; D041981:Gastrointestinal Tract / Q000187:drug effects / Q000254:growth & development; D006358:Hot Temperature; D009753:Nutritive Value; D011096:Polygalacturonase / Q000378:metabolism; D011897:Random Allocation; D031307:Vicia faba / Q000737:chemistry*
chemical_list: D030161:Avian Proteins; D002265:Carboxylic Ester Hydrolases; C022711:tannase; D011096:Polygalacturonase; D043364:Endo-1,4-beta Xylanases
keywords: Broilers; Vicia faba; digestibility; energy content; enzyme preparations; heat treatment; tannase