Department of Poultry Science, Mississippi State University, Mississippi State, MS, USA.
Department of Animal Science, University of Tennessee, Knoxville, TN, USA.
Poult Sci. 2021 Apr;100(4):100973. doi: 10.1016/j.psj.2020.12.070. Epub 2020 Dec 31.
In a companion study, we found that inclusion of different doses of riboflavin affected growth performance of Ross 708 male broilers' responses to coccidial challenge (by 5 Eimeria spp on day 14 of age) and dietary Bacillus subtilis (B. subtilis) supplementation. The current study was conducted to further test whether supplementation of B. subtilis and riboflavin will reduce negative impact and inflammation caused by Eimeria spp proliferation and help proper function of internal organs. A total of 1,248 Ross × Ross 708 male broiler chicks were randomly placed in 96 floor pens (8 blocks, 12 treatments). Treatments were arranged in a 3 (riboflavin) × 2 (B. subtilis) × 2 (Coccidial challenge) factorial arrangement in a randomized complete block design. Coccidial challenge reduced the weight of sampled birds on day 27 and day 36 and increased the relative weights of the internal organs of proventriculus, duodenum, jejunum, ileum, and spleen to BW on day 27, which may be because of inflammation caused by proliferation of Eimeria spp. The increased relative weights of duodenum, jejunum, ileum, and spleen on coccidial challenged birds were lost on day 36. Correlation analysis also indicated that the jejunum weight was positively related to villus height, Eimeria acervulina, and Eimeria maxima on day 27 but was not on day 36. The loss of the positive relationships may be because of recovery of the birds from coccidiosis on day 36. Even though the coccidial challenge and riboflavin interactively affected feed conversion ratio and BW gain and supplementation of dietary B. subtilis reduced mortality from day 35 to 42 in the companion study, the same response of internal organs was not observed in the current study. Coccidial challenge compromised development of internal organs of Ross 708 male broilers at an early age, but the negative effects subsided with age of birds rather than supplementation of riboflavin and B. subtilis at current tested levels under our experimental set up.
在一项伴随研究中，我们发现添加不同剂量的核黄素会影响 Ross 708 雄性肉鸡对球虫挑战（在 14 日龄时使用 5 种艾美耳球虫）和饲粮枯草芽孢杆菌（B. subtilis）补充的生长性能的反应。本研究旨在进一步测试 B. subtilis 和核黄素的补充是否会减轻由艾美耳球虫增殖引起的负面影响和炎症，并有助于内部器官的正常功能。总共 1248 只 Ross×Ross 708 雄性肉鸡雏鸡被随机放置在 96 个地板笼（8 个块，12 个处理）中。处理采用 3（核黄素）×2（枯草芽孢杆菌）×2（球虫挑战）因子设计，在随机完全区组设计中安排。球虫挑战降低了 27 日龄和 36 日龄采样鸟类的体重，并增加了 27 日龄前胃、十二指肠、空肠、回肠和脾脏相对于 BW 的相对重量，这可能是由于艾美耳球虫增殖引起的炎症。感染球虫的鸟类的十二指肠、空肠、回肠和脾脏的相对重量在 36 日龄时丧失。相关分析还表明，27 日龄时空肠重量与绒毛高度、艾美耳堆形艾美耳球虫和巨型艾美耳球虫呈正相关，但 36 日龄时则无相关性。这种正相关关系的丧失可能是由于鸟类在 36 日龄时从球虫病中恢复。尽管在伴随研究中，球虫挑战和核黄素相互作用影响了饲料转化率和 BW 增益，饲粮枯草芽孢杆菌的补充降低了 35 日龄至 42 日龄的死亡率，但在当前研究中并未观察到内部器官的相同反应。球虫挑战损害了 Ross 708 雄性肉鸡早期内部器官的发育，但随着鸟类年龄的增长，负面影响减弱，而不是在我们的实验设置下，以当前测试的水平补充核黄素和 B. subtilis。
