Wageningen University & Research, Animal Nutrition Group, Wageningen 6708 WD, The Netherlands; Trouw Nutrition R&D, Amersfoort 3811 MH, The Netherlands.
Trouw Nutrition R&D, Amersfoort 3811 MH, The Netherlands.
Poult Sci. 2021 Mar;100(3):100913. doi: 10.1016/j.psj.2020.12.013. Epub 2020 Dec 9.
Chelating agents can be used to improve the nutritional availability of trace minerals within the gastrointestinal tract. This study was conducted to determine the effect of a novel chelating agents, L-glutamic acid N,N-diacetic acid (GLDA), a biodegradable alternative to ethylenediaminetetraacetic acid on the nutritional bioavailability of zinc in broilers. Twelve dietary treatments were allocated to 96 pens in a randomized block design. Pens contained 10 Ross 308 male broilers in a factorial design with 6 incremental zinc levels (40, 45, 50, 60, 80, and 120 ppm of total Zn), with and without inclusion of GLDA (0 and 100 ppm) as respective factors. Experimental diets were supplied from day 7 to 21/22 and serum, liver and tibia Zn content were determined in 3 birds per pen. Growth performance and liver characteristics were not affected by dietary treatments, but both supplemental Zn and GLDA enhanced tibia and serum zinc concentration. The positive effect of GLDA was observed at all levels of the dietary Zn addition. The amount of zinc needed to reach 95% of the asymptotic Zn response was determined using nonlinear regression. When GLDA was included in the diet, based on tibia Zn, the same Zn status was achieved with a 19 ppm smaller Zn dose while based on serum Zn this was 27 ppm less Zn. Dietary GLDA reduces supplemental Zn needs to fulfill nutritional demands as defined by tibia Zn and serum Zn response. Considering the positive effect on the nutritional availability of Zn in broilers, GLDA presents an opportunity as biodegradable additive, to reduce Zn supplementation to livestock and thereby reducing Zn excretion into the environment, while fulfilling the nutrition Zn needs of farmed animals.
螯合剂可用于提高胃肠道内痕量矿物质的营养可用性。本研究旨在确定新型螯合剂 L-谷氨酸 N,N-二乙酸（GLDA）作为乙二胺四乙酸的可生物降解替代品对肉鸡锌的营养生物利用度的影响。12 种饲粮处理分配到随机区组设计的 96 个栏位中。每个栏位包含 10 只罗斯 308 雄性肉鸡，采用 6 个递增锌水平（40、45、50、60、80 和 120ppm 总 Zn）和有无 GLDA（0 和 100ppm）的析因设计。从第 7 天到 21/22 天，每栏 3 只鸡提供实验饲粮，测定血清、肝脏和胫骨 Zn 含量。饲粮处理对生长性能和肝脏特性没有影响，但补充 Zn 和 GLDA 均提高了胫骨和血清 Zn 浓度。在添加 Zn 的所有水平均观察到 GLDA 的积极作用。使用非线性回归确定达到 95%渐近 Zn 响应所需的锌量。当饲粮中包含 GLDA 时，基于胫骨 Zn，添加 19ppm 更小的 Zn 剂量即可达到相同的 Zn 状态，而基于血清 Zn，则少添加 27ppm 的 Zn。饲粮 GLDA 减少了满足胫骨 Zn 和血清 Zn 响应定义的营养需求所需的补充 Zn 量。考虑到对肉鸡 Zn 营养有效性的积极影响，GLDA 作为可生物降解的添加剂为减少牲畜 Zn 补充提供了机会，从而减少 Zn 排泄到环境中，同时满足养殖动物的 Zn 营养需求。
