本研究的目的是比较补充muramidase(MUR)和2种植物源性添加剂对生长性能的影响。肠道形态学,细菌负荷,以及在类似田间条件下饲养的肉鸡的短链脂肪酸(SCFA)的产生。共随机抽取6400只日龄罗斯308只肉鸡,分装到32支地面围栏中,有200只小鸡(100只雄性和100只雌性)/笔。治疗组为未补充的对照组,实验组补充了35,000LSU(F)/kg饲料的MUR,以100g/吨饲料计的植物性1(Phyto1,基于百里酚),或以60克/吨饲料的植物性2(基于生物碱的植物性2),总周期为41d。应用了4阶段进给程序(启动程序,种植者,终结者和提款)。评估的参数是:生长性能,car体产量,空肠内容物和排泄物中的muranic酸浓度,肝酶浓度,肠道形态学,盲肠内容物中的细菌计数以及短链和支链脂肪酸(SCFA和BCFA)。通过ANOVA分析数据,并使用Tukey检验来分离平均值。与其他组相比,空肠中的可溶性胞壁酸(MurN)随着MUR和Phyto2的补充而增加(P=0.0001),但只有补充MUR才会增加粪便中MurN的浓度。与对照组相比,补充所有饲料添加剂改善了体重增加和体重校正的饲料转化率(P=0.0001)。与对照组或其他补充组相比,MUR增加了绒毛高度(VH)(P=0.0001),导致大多数SCFA的浓度最高,总BCFA,总SCFA(P<0.05)。总之,在肉仔鸡的日粮中添加MUR和植物基因改善了生长性能,但是MUR,只有,能够有效降解两个肠段中的肽聚糖(PGN),以及增加有益菌和SCFA产量的丰度。
The objective of the present study was to compare the effectiveness of dietary supplementation of
muramidase (MUR) and 2 phytogenic additives on the growth performance, intestinal morphology, bacteria load, and production of short-chain fatty acids (SCFA) of broiler chickens raised under field-like conditions. A total of 6,400 day-old Ross 308 broiler chicks were randomly selected and distributed into 32 floor pens, with 200 chicks (100 males and 100 females)/pen. The treatment groups were an unsupplemented control, and the experimental groups supplemented with MUR at 35,000 LSU(F)/kg of feed, phytogenic 1 (Phyto 1, based on thymol) at 100g/ton feed, or phytogenic 2 (Phyto 2, based on alkaloids) at 60g/ton feed, for a total period of 41 d. A 4-phase feeding program was applied (starter, grower, finisher and withdrawal). The paramenters evaluated were: growth performance, carcass yield, concentration of muranic acid in the jejunum content and excreta, liver enzyme concentration, intestinal morphology, and bacteria enumeration and short and branch chain fatty acids (SCFA and BCFA) in the cecal content. Data were analyzed by ANOVA and Tukey\'s test was used to separate the means. Soluble muramic acid (MurN) in the jejunum increased with the supplementation of MUR and Phyto 2 when compared to the other groups (P = 0.0001), but only the supplementation of MUR increased the concentration of MurN in the excreta. The supplementation of all feed additives improved the body weight gain and the body weight corrected feed conversion ratio when compared to the control group (P = 0.0001). MUR increased villus heigh (VH) when compared to the control or the other supplemented groups (P = 0.0001), and led to the highest concentration of most SCFA, total BCFA, and total SCFA (P < 0.05). In conclusion, the supplementation of MUR and phytogenics to the diets of broiler chickens improved the growth performance, but MUR, only, was capable of effectively degrading peptidoglycans (PGNs) in both intestinal segments, as well as to increase the abundance of beneficial bacteria and SCFA production.