Sahin Nurhan, Sahin Kazim, Onderci Muhittin, Sarkar Fazlul H, Doerge Daniel, Prasad Ananda, Kucuk Omer
Department of Animal Nutrition, Faculty of Veterinary Science, Firat University, Elazig, Turkey.
Exp Anim. 2006 Apr;55(2):75-82. doi: 10.1538/expanim.55.75.
Genistein is a powerful antioxidant and plays a role in calcium and bone metabolism. We evaluated the efficacy of dietary supplementation with genistein on the nutrient use and mineral concentrations in tibia and serum of quails reared at high environmental temperature (34 degrees C). Two hundred and forty Japanese quails (10 days old) were randomly assigned to 8 treatment groups consisting of 10 replicates of 3 birds. The birds were kept in a temperature-controlled room at 22 degrees C (Thermoneutral, TN groups) or 34 degrees C (for 8 h/d; 09.00 am-05.00 pm; Heat stress, HS groups). Birds were fed either a basal diet (TN and HS) or the basal diet supplemented with 200, 400 or 800 mg of genistein/kg of diet. Heat exposure decreased apparent nutrient digestibility and bone mineralization when the basal diet was fed (P < 0.001). Apparent digestibility of dry matter (DM) (P < 0.05), crude protein (CP) (P < 0.05) and ash (P < 0.01) was significantly improved by genistein supplementation. However, this improvement was not in direct proportion to increased doses of supplement since there was no difference when diets included either 400 or 800 mg genistein/kg of diet (P < 0.05) in birds reared under heat stress. The amounts of Ca, P, Mg, Mn, Zn, Fe and Cu in the excreta decreased (P < 0.01), while Ca, P, Mg, Mn, Zn and Cu concentrations in tibia ash increased in quails reared under heat stress conditions (P < 0.01) with genistein supplementation. Ca and P concentrations in tibia ash were also increased in birds kept under thermoneutral conditions with genistein supplementation. Increased serum alkaline phosphatase activity (P < 0.01) was associated with increasing dietary genistein in all groups. In conclusion, genistein supplementation to the basal diet improved digestibility of CP, DM and ash and levels of Ca and P and bone mineralization in quails reared under heat stress conditions.
金雀异黄素是一种强大的抗氧化剂，在钙和骨代谢中发挥作用。我们评估了在高环境温度（34摄氏度）下饲养的鹌鹑日粮中添加金雀异黄素对营养物质利用以及胫骨和血清中矿物质浓度的影响。240只日本鹌鹑（10日龄）被随机分配到8个处理组，每组3只鸟，重复10次。这些鸟被饲养在温度控制在22摄氏度的房间（热中性，TN组）或34摄氏度的房间（每天8小时；上午9点至下午5点；热应激，HS组）。给鸟喂食基础日粮（TN组和HS组）或添加了200、400或800毫克金雀异黄素/千克日粮的基础日粮。喂食基础日粮时，热暴露会降低表观营养物质消化率和骨矿化（P < 0.001）。添加金雀异黄素显著提高了干物质（DM）（P < 0.05）、粗蛋白（CP）（P < 0.05）和灰分（P < 0.01）的表观消化率。然而，这种改善与补充剂剂量的增加并非直接成比例，因为在热应激条件下饲养的鸟中，日粮中含有400或800毫克金雀异黄素/千克日粮时没有差异（P < 0.05）。热应激条件下饲养的鹌鹑补充金雀异黄素后，排泄物中钙、磷、镁、锰、锌、铁和铜的含量降低（P < 0.01），而胫骨灰分中钙、磷、镁、锰、锌和铜的浓度增加（P < 0.01）。在热中性条件下饲养的鸟补充金雀异黄素后，胫骨灰分中的钙和磷浓度也增加。所有组中血清碱性磷酸酶活性的增加（P < 0.01）与日粮中添加金雀异黄素有关。总之，在基础日粮中添加金雀异黄素可提高热应激条件下饲养的鹌鹑对CP、DM和灰分的消化率以及钙、磷水平和骨矿化。
