This study determined the effects of different dietary crude protein (CP) levels on ammonia emission (NH3), litter and manure composition, nitrogen (N) losses, and water intake in broiler breeders. A total of 480 females and 64 males (Ross 308) 20 wk of age were randomly allotted to 2 dietary treatments with 8 replicates of 30 females and 4 males per replicate. Birds were fed either high CP (CPh) or low CP diets (CPl) supplemented with free amino acids (AA). Both diets consisted of 3 sub-diets; 1 for each phase of the laying period. Diets were formulated to be iso-caloric and calculated CP content of the CPl diets was 15 g/kg lower than the CPh diets (Breeder 1 (23 to 34 wk): 135 vs. 150, Breeder 2 (35 to 46 wk): 125 vs. 140 and Breeder 3 (47 to 60 wk of age): 115 vs. 130 g/kg, respectively). Pens consisted of an elevated slatted floor (25% of the floor surface) and a litter floor. Water and feed intake were recorded daily. Litter (floor) and manure (below slatted floor) composition and ammonia concentration were measured at 34, 44, and 54 wk of age. Ammonia concentration was measured using a flux chamber on top of the litter or manure. Estimated N losses were calculated. Dietary protein level did not affect water intake and dry matter (DM) content of the litter or manure. Compared to birds fed the CPh diets, the litter and manure samples of broiler breeders fed the CPl had 8% lower total-N and 13% lower ammonia-N content resulting in a 9% lower ammonia concentration, 9% lower ammonia emission, and 11% lower total-N losses. In conclusion, this study shows that reducing CP level in the diet of broiler breeders reduces ammonia emission and total N-losses from litter and manure.

中文翻译：

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日粮粗蛋白水平对肉种鸡氨排放、垫料和粪便组成、氮损失和饮水量的影响。

本研究确定了不同日粮粗蛋白 (CP) 水平对肉种鸡氨排放 (NH3)、垫料和粪便组成、氮 (N) 损失和饮水量的影响。总共 480 名女性和 64 名男性 (Ross 308) 20 周龄被随机分配到 2 个饮食处理，每个重复 8 个重复，每个重复 30 名女性和 4 名男性。给鸡喂食补充有游离氨基酸（AA）的高CP（CPh）或低CP日粮（CP1）。两种饮食均由 3 种子饮食组成；1 为产蛋期的每个阶段。将日粮配制成等热量的，计算出的 CP1 日粮的 CP 含量比 CPh 日粮低 15 g/kg（育种者 1（23 至 34 周）：135 对 150，育种者 2（35 至 46 周）： 125 对 140 和饲养员 3（47 至 60 周龄）：分别为 115 对 130 g/kg）。围栏由高架板条地板（占地板表面的 25%）和垫料地板组成。每天记录水和饲料摄入量。在 34、44 和 54 周龄时测量垫料（地板）和粪​​便（板条地板以下）成分和氨浓度。使用垫料或粪便顶部的通量室测量氨浓度。计算了估计的 N 损失。日粮蛋白质水平不影响垫料或粪便的水摄入量和干物质 (DM) 含量。与饲喂 CPh 日粮的鸡相比，饲喂 CP1 的肉种鸡的垫料和粪便样本的总氮含量降低 8%，氨氮含量降低 13%，导致氨浓度降低 9%，氨排放降低 9%，并且总氮损失降低 11%。综上所述，