Department of Animal Biosciences, University of Guelph, Guelph, ON, Canada, N1G2W1.
DSM Nutritional Products Inc., Parsippany, NJ, 07054, USA.
Poult Sci. 2021 Sep;100(9):101362. doi: 10.1016/j.psj.2021.101362. Epub 2021 Jun 29.
Growth performance, organ weight, ceca digesta short chain fatty acids (SCFA), jejunal histomorphometry, tibia ash, apparent retention (AR) of components and caloric efficiency were investigated in broiler chicken strains differing in growth rate fed diets with multienzyme supplement (MES). The strains differed in estimated time to reach 2.1 kg BW: 37, 43, 47, and 50 d and were designated C, F, J, and N, respectively. A corn-soybean meal diet was formulated for 2-phase program (starter and grower) and fed without or with MES containing phytase, protease and fiber-degrading enzymes. A total of 640-day-old chicks (42.3 + 0.01 g/bird) were housed in cages (5 cockerels and 5 pullets/cage) and allocated to give 8 replicates/ strain and diet combination. Equal amount of feed was fed based on observed ad-libitum intake of C strain in the starter (d 0-14) and grower (d 15-28). Body weight was monitored, grab excreta samples taken and at completion of allocated feed one bird per cage necropsied for samples. With exception of P, apparent metabolizable energy corrected for nitrogen (AMEn) and ceca digesta acetic acid, there was no (P > 0.05) interaction between strain and MES on examined responses. Strains differed (P < 0.01) on growth, FCR, gizzard weight, tibia ash, breast weight, ceca digesta concentration of lactic, propionic, and isobutyric acid and caloric efficiency. The final body weight (BW) was 1,344, 1,134, 959, and 916 g/bird for C, F, J, and N, respectively. Corresponding caloric efficiency was 4,930, 5,807, 6,680 and 7,199 kcal/kg BW gain, respectively. Birds fed MES had higher BW gain (P < 0.05) in grower phase, larger gizzard, higher AR of CP, crude fat, neutral detergent fiber, and Ca than non-MES birds. In conclusion, growth rate influenced organ attributes, nutrient, and caloric utilization. Enzyme supplementation improved growth in grower phase and nutrient utilization independent of strain, suggesting that effects of feed enzymes are not influenced by inherent growth rate.
研究了在生长速度不同的肉鸡品种中，添加多酶制剂（MES）对生长性能、器官重量、盲肠内容物短链脂肪酸（SCFA）、空肠组织形态、胫骨灰分、成分表观保留率（AR）和热能效率的影响。这些品种的估计达到 2.1kgBW 的时间不同：37、43、47 和 50 天，分别命名为 C、F、J 和 N。设计了一个玉米-豆粕日粮，用于 2 阶段方案（起始和生长），并分别饲喂不含或含植酸酶、蛋白酶和纤维降解酶的 MES。共 640 日龄的雏鸡（42.3±0.01g/只）饲养在笼中（每笼 5 只公鸡和 5 只母鸡），并按 C 品种在起始阶段（d0-14）和生长阶段（d15-28）的自由采食量进行分配，以保证每只鸡都能吃到等量的饲料。监测体重，采集抓取的粪便样本，并在完成分配的饲料后，对每笼中的一只鸟进行尸检以获取样本。除了 P，氮校正表观代谢能（AMEn）和盲肠内容物乙酸外，品种和 MES 对所检查的反应没有交互作用（P>0.05）。品种之间在生长、FCR、肌胃重量、胫骨灰分、胸肌重量、盲肠内容物乳酸、丙酸和异丁酸浓度和热能效率方面存在差异（P<0.01）。最终体重（BW）分别为 C、F、J 和 N 品种的 1344、1134、959 和 916g/只。相应的热能效率分别为 4930、5807、6680 和 7199kcal/kgBW 增重。在生长阶段，饲喂 MES 的鸡体重增加（P<0.05），肌胃更大，CP、粗脂肪、中性洗涤剂纤维和 Ca 的 AR 更高。总之，生长速度影响器官属性、营养物质和热量利用。酶制剂的补充提高了生长阶段的生长速度和养分利用率，与品种无关，这表明饲料酶的作用不受固有生长速度的影响。
