The metabolizable energy value of lecithin and factors affecting its efficacy in improving the digestibility of fat in broilers － fat source and age

• Main Authors: Chen, Min-Hsiu, 陳敏修
• Other Authors: Shu-Hsing Chiang
• Format: Others
• Language: zh-TW
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/77689875958386995725

碩士 === 東海大學 === 畜產學研究所 === 84 === The objects of the study were to investigate (1) whether fatsource and age of chicks affecting the efficacy of lecithin inimproving the digestibility of fat in broilers and (2) themetabolizable energy value of lecithin. Experiment 1, one hundred and twenty 3-d old Arbor Acres chickswere allotted to a 2×2 factorial design arrangement. Chicks werefed diets supplemented with 8% of soybean oil or tallow and 0 or2% of lecithin. Lecithin was supplemented by replacing starch ofthe diets. And 0.25% Cr2O3 was added in diet as an indicator.There were six replicates each treatment with five chicks eachreplicate. Chicks were fed in a heated wire-floored metabolismcage; excreta were collected for 5d each starting from age 7 and21 d. The results indicated that the digestibility of soybean oilwas higher than the digestibility of tallow (P< 0.01). Elderchicks had a higher fat digestibility than younger chicks had (P <0.01). Adding lecithin to diets improved fat digestibility (P <0.06). There were no interaction between fat source×lecithin andbetween lecithin×age (P > 0.05). The digestibility of fatty acidsin soybean oil was higher than the fatty acids in tallow (C16:0,C18:0, C18:2 and C18:3: P < 0.01; C18:1: P < 0.05). Elder chickshad a higher individual fatty acid digestibility than youngerchicks had (C16:0, C18:0, C18:1, C18:2 and C18:3: P < 0.01).Adding lecithin to diets could improve C16:0 and C18:0digestibility (P < 0.01). But not the digestibility of C18:1,C18:2 and C18:3 (P > 0.05). Experiment 2, one hundred and twenty 8-d old Arbor Acres chickswere allotted to four treatments and were fed one of four corn- SBMdiets: (1) Diet 1, containing 20% glucose; (2) Diet 2, containing15% glucose and 5% lecithin; (3) Diet 3, containing 10% glucoseand 10% lecithin; (4) Diet 4, containing 20% lecithin. And 0.25%Cr2O3 was added in diet as an indicator. There were six replicateseach treatment with five chicks each replicate. Chicks were fed ina heated wire-floored metabolism cage; excreta were collected from14 to 21-d old. The metabolizable value of lecithin was determinedby extrapolating lecithin to 100% of diet according to the linearregression between the metabolizable energy of diets and thelecithin contents. The determined metabolizable energy of lecithinwas 6147 kcal/kg.