Implications of excreta uric acid concentrations in broilers offered reduced crude protein diets and dietary glycine requirements for uric acid synthesis  

作　　者：Peter H.Selle David I.Cantor Leon R.McQuade Bernard V.McInerney Juliano Cesar de Paula Dorigam Shemil P.Macelline Peter V.Chrystal Sonia Y.Liu 

机构地区：[1]Poultry Research Foundation within The University of Sydney,Camden,NSW 2570,Australia [2]Sydney School of Veterinary Science,The University of Sydney,Sydney,NSW 2006,Australia [3]Australian Proteome Analysis Facility,Macquarie University,Sydney,NSW 2109,Australia [4]Evonik Nutrition and Care GmbH,Hanau-Wolfgang 63547,Germany [5]School of Life and Environmental Sciences,Faculty of Science,The University of Sydney,Sydney,NSW 2006,Australia [6]Baiada Poultry Pty Limited,Pendle Hill,NSW 2145,Australia

出　　处：《Animal Nutrition》2021年第4期939-946,共8页动物营养（英文版）

摘　　要：In a previous experiment,male Ross 308 broiler chickens were offered dietary treatments with 3 levels of crude protein(222,193,165 g/kg)and 3 feed grains(ground maize,ground wheat,whole wheat)from 7 to 35 d post-hatch.Maize-based diets supported superior growth performance in comparison to wheatbased diets.Uric acid concentrations in excreta were retrospectively determined and related to total nitrogen(N)excreta concentrations.Uric acid concentrations ranged from 28.5 to 69.4 mg/g and proportions of uric acid-N to total excreta-N ranged from 27.4%to 42.6%in broiler chickens offered the 3×3 factorial array of dietary treatments.Proportions of uric acid-N to total N in excreta in birds offered the165 g/kg CP,maize-based diet were significantly lower by 10.6 percentage units(27.4%versus 38.0%;P=0.00057)than their wheat-based counterparts.Total excreta analysed had been collected from 35 to37 d post-hatch when feed intakes and excreta outputs were monitored.There were linear relationships between proportions of uric acid-N to total N in excreta in birds offered the three 165 g/kg CP diets with weight gain(r=-0.587;P=0.010),feed intake(r=-0.526;P=0.025)and feed conversion ratios(r=0.635;P=0.005).The possibility that increasing uric acid-N proportions in excreta is indicative of excessive ammonia accumulations compromising growth performance is discussed.The mean proportion of dietary glycine involved in uric acid excretion was 49.2%across all dietary treatments but ranged from 25.0%to 80.9%.Thus,the appropriate amount of dietary glycine is variable and largely dependent on the volume of uric acid synthesised and excreted.

关 键 词：Ammonia Broiler chicken GLYCINE Reduced crude protein diet Uric acid 

分 类 号：S831.5[农业科学—畜牧学]