Rodewald ElsiAnna, Jasek Brooke, Zhang Li, Roberts Stacey, Bortoluzzi Cristiano, Adhikari Pratima
Department of Poultry Science, Mississippi State University, Starkville, MS 39762, USA.
dsm-firmenich, Animal Nutrition and Health, North America, Belvidere, NJ 07823, USA.
Animals (Basel). 2025 Jul 16;15(14):2095. doi: 10.3390/ani15142095.
The objective of this study was to determine the effects of two levels of a precision biotic (PB) within a reduced CP diet for performance, digestibility, and blood biomarkers in Dekalb White laying hens from 24 to 42 weeks of age. A total of four diets were fed: (1) an industry-standard positive control (PC) diet with a formulated CP level of 17.5%; (2) a negative control (NC) diet with a formulated CP level of 15.5%; (3) NC with 0.5 kg/ton PB (NC+PB1); (4) NC with 0.7 kg/ton PB (NC+PB2). The NC diet decreased hen-day egg production compared to the PC diet, and supplementation with both levels of PB led to intermediate levels of production. There was a similar trend for the feed conversion ratio (FCR), measured in kilograms of feed per dozen eggs. Feed cost was lower in the reduced CP diets compared to the PC. Apparent total tract digestibility was decreased with PB supplementation without differences in apparent ileal digestibility. The increased plasma uric acid levels in the NC+PB2 group suggest a shift in protein metabolism toward higher efficiency in ammonia detoxification. While more research is needed on PB, this research suggests that supplementation with PB in laying hens could potentially improve performance parameters.
本研究的目的是确定在24至42周龄的迪卡白蛋鸡的低粗蛋白（CP）日粮中添加两种水平的精准生物制剂（PB）对生产性能、消化率和血液生物标志物的影响。总共投喂了四种日粮：（1）一种行业标准的阳性对照（PC）日粮，其配方粗蛋白水平为17.5%；（2）一种阴性对照（NC）日粮，其配方粗蛋白水平为15.5%；（3）添加0.5千克/吨PB的NC日粮（NC+PB1）；（4）添加0.7千克/吨PB的NC日粮（NC+PB2）。与PC日粮相比，NC日粮降低了母鸡日产蛋量，添加两种水平的PB均使产蛋量达到中间水平。以每打鸡蛋的饲料千克数衡量的饲料转化率（FCR）也有类似趋势。与PC日粮相比，低粗蛋白日粮的饲料成本更低。添加PB后，表观全肠道消化率降低，但表观回肠消化率没有差异。NC+PB2组血浆尿酸水平升高表明蛋白质代谢向更高效率的氨解毒方向转变。虽然关于PB还需要更多研究，但本研究表明在蛋鸡日粮中添加PB可能会改善生产性能参数。
