Xu Y, Stark C R, Ferket P R, Williams C M, Nusairat B, Brake J
Prestage Department of Poultry Science, North Carolina State University, Raleigh, 27695-7608.
Prestage Department of Poultry Science, North Carolina State University, Raleigh, 27695-7608
Poult Sci. 2015 Mar;94(3):362-70. doi: 10.3382/ps/peu057. Epub 2015 Feb 12.
Two 49 d floor pen studies were conducted to evaluate the effects of litter type and dietary coarse ground corn (CC) inclusion on broiler live performance, gastrointestinal tract (GIT) development, and litter characteristics. Experiment 1 was a 2×2 factorial arrangement of 2 genders (male or female) and 2 CC levels (0 or 50%). From 15 to 35 d, the addition of CC decreased feed intake (P<0.01) and BW gain (P<0.05) of males but not females. The inclusion of CC decreased feed intake (P<0.01) and BW gain (P<0.01) from 0 to 49 d but improved adjusted feed conversion ratio (AdjFCR) from 35 to 49 d (P<0.05). Male broilers exhibited better live performance than females during the study as evidenced by greater feed intake (P<0.01) and BW gain (P<0.01), and improved FCR (P<0.01), but with increased mortality (P<0.05). The inclusion of CC increased relative gizzard weight (P<0.01) and decreased relative proventriculus weight (P<0.01) at 49 d. Experiment 2 was a 2×2 factorial arrangement of 2 CC levels (0 or 50%) and 2 litter types (ground old litter or new wood shavings litter). The inclusion of CC decreased feed intake throughout the experiment without affecting final BW when only males were used and improved FCR after 25 d (P<0.01). New litter improved FCR from 1 to 14 d (P<0.01). At 49 d, the birds fed the CC diet had reduced excreta nitrogen (P<0.05) and litter moisture (P<0.05). In conclusion, 50% CC inclusion initially produced negative effects on live performance that became positive as BW increased. The effects of CC became evident at an earlier age for males. New litter had only a marginal benefit on broiler live performance.
进行了两项为期49天的地面平养试验,以评估垫料类型和日粮中粗磨玉米(CC)添加量对肉鸡生长性能、胃肠道(GIT)发育及垫料特性的影响。试验1采用2×2析因设计,包括2个性别(雄性或雌性)和2个CC水平(0%或50%)。在15至35日龄期间,添加CC降低了雄性肉鸡的采食量(P<0.01)和体重增加量(P<0.05),但对雌性肉鸡无影响。从0至49日龄,添加CC降低了采食量(P<0.01)和体重增加量(P<0.01),但改善了35至49日龄的校正饲料转化率(AdjFCR)(P<0.05)。在试验期间,雄性肉鸡的生长性能优于雌性肉鸡,表现为采食量更高(P<0.01)、体重增加量更大(P<0.01)、饲料转化率更好(P<0.01),但死亡率更高(P<0.05)。在49日龄时,添加CC增加了肌胃相对重量(P<0.01)并降低了腺胃相对重量(P<0.01)。试验2采用2×2析因设计,包括2个CC水平(0%或50%)和2种垫料类型(旧垫料或新刨花垫料)。仅使用雄性肉鸡时,添加CC在整个试验期间降低了采食量,但不影响最终体重,并在25日龄后改善了饲料转化率(P<0.01)。新垫料在1至14日龄改善了饲料转化率(P<0.01)。在49日龄时,饲喂CC日粮的肉鸡粪便氮含量(P<0.05)和垫料湿度降低(P<0.05)。总之,添加50%的CC最初对生长性能产生负面影响,但随着体重增加变为正面影响。CC对雄性肉鸡的影响在更早的年龄就变得明显。新垫料对肉鸡生长性能的益处有限。