Kalia Sahil, Magnuson Andrew D, Sun Tao, Liu Guanchen, Kim Woo Kyun, Johnson Zackary, Lei Xin Gen
Department of Animal Science, Cornell University, 252 Morrison Hall, Ithaca, NY, 14850, USA.
Department of Poultry Science, University of Georgia, Athens, GA, USA.
J Anim Sci Biotechnol. 2023 Mar 16;14(1):27. doi: 10.1186/s40104-023-00842-3.
Docosahexaenoic acid (DHA) and calcidiol could be enriched in chicken for improving public nutrition and health. It remains unclear if supranutritional levels of DHA and calcidiol impair growth performance or metabolism of broiler chickens. This study was to determine singular and combined effects of high levels of supplemental DHA-rich microalgal biomass or oil and calcidiol on growth performance, concentrations of triglycerides, cholesterol, and nonesterfied fatty acids in plasma, liver, breast, and thigh, and biophysical properties of tibia.
In Exp. 1, 144 day-old Cornish chicks were divided into 4 groups (6 cages/treatment, 6 birds/cage), and were fed a corn-soybean meal basal diet (BD), BD + 10,000 IU calcidiol/kg (BD + Cal), BD + 1% DHA-rich Aurantiochytrium (1.2 g DHA/kg; BD + DHA), and BD + Cal + DHA for 6 weeks. In Exp. 2, 180 day-old chicks were divided into 5 groups, and were fed: BD, BD + DHA (0.33% to 0.66% oil, 1.5 to 3.0 g DHA/kg), BD + DHA + EPA (1.9% to 3.8% eicosapentaenoic acid-rich Nannochloropsis sp. CO18, 0.3 to 0.6 g EPA/kg), BD + DHA + calcidiol (6000 to 12,000 IU/kg diet), and BD + DHA + EPA + Cal for 6 weeks.
Birds fed BD + Cal diet in Exp. 1 and BD + DHA + EPA diet in Exp. 2 had higher (P < 0.05) body weight gain (10%-11%) and gain:feed ratio (7%), and lower (P < 0.05) total cholesterol and triglyceride concentrations in plasma (18%-54%), liver (8%-26%), breast (19%-26%), and thigh (10%-19%), respectively, over the controls. The two diets also improved (P < 0.05) tibial breaking strength (8%-24%), total bone volume (2%-13%), and (or) bone mineral density (3%-19%) of chickens.
Supranutrition of dietary calcidiol and DHA alone or together did not produce adverse effects, but led to moderate improvements of growth performance, lipid profiles of plasma and muscle, and bone properties of broiler chickens.
二十二碳六烯酸（DHA）和骨化二醇可在鸡肉中富集，以改善公众营养与健康状况。目前尚不清楚超营养水平的DHA和骨化二醇是否会损害肉鸡的生长性能或代谢。本研究旨在确定高水平补充富含DHA的微藻生物质或油脂以及骨化二醇对生长性能、血浆、肝脏、胸肌和大腿中甘油三酯、胆固醇和非酯化脂肪酸浓度以及胫骨生物物理特性的单一和联合影响。
在实验1中，将144只1日龄的科尼什鸡分为4组（每组6个笼子，每个笼子6只鸡），分别饲喂玉米 - 豆粕基础日粮（BD）、BD + 10000 IU骨化二醇/千克（BD + Cal）、BD + 1%富含DHA的金藻（1.2克DHA/千克；BD + DHA）以及BD + Cal + DHA，持续6周。在实验2中，将180只1日龄的鸡分为5组，分别饲喂：BD、BD + DHA（0.33%至0.66%油脂，1.5至3.0克DHA/千克）、BD + DHA + EPA（1.9%至3.8%富含二十碳五烯酸的微拟球藻CO18，0.3至0.6克EPA/千克）、BD + DHA + 骨化二醇（6000至12000 IU/千克日粮）以及BD + DHA + EPA + Cal，持续6周。
在实验1中，饲喂BD + Cal日粮的鸡以及在实验2中饲喂BD + DHA + EPA日粮的鸡，与对照组相比，体重增加更高（P < 0.05）（10% - 11%），料重比更高（7%），血浆（18% - 54%）、肝脏（8% - 26%）、胸肌（19% - 26%）和大腿（10% - 19%）中的总胆固醇和甘油三酯浓度更低（P < 0.05）。这两种日粮还改善了（P < 0.05）鸡的胫骨断裂强度（8% - 24%）、总骨体积（2% - 13%）和（或）骨矿物质密度（3% - 19%）。
日粮中单独或同时超营养添加骨化二醇和DHA不会产生不良影响，反而会适度改善肉鸡的生长性能、血浆和肌肉的脂质谱以及骨骼特性。
