|摘要: ||本試驗旨在探討飼糧中菸[生僉]酸與色胺酸添加量對雛鵝生長性能、血液與骨骼性狀之影響。試驗動物使用商用1日齡白羅曼雛鵝120隻，試驗採2×5複因子試驗(Factorial experiment)，二種色胺酸含量(0.16及0.26%)與五種菸[生僉]酸添加量(0、25、50、75及100 ppm)之處理組合，每一處理組鵝隻6隻，公母各半，兩重複，逢機分配於20欄內，試驗採籠飼飼養，試驗期四週，每週秤量雛鵝之個別體重一次，並記錄各處理組之飼料採食量。試驗結束時，每處理組採取體重相近之雛鵝4隻(2公2母)，由翼下靜脈採取血液後犧牲、解剖，採取肝臟和脛骨，供測定血清中三酸甘油酯、膽固醇、總脂質與離子濃度，以及脛骨重量、長度、直徑、強度、相對重量、灰分百分比、鈣與磷之含量。|
試驗結果顯示，在色胺酸含量方面，隻日增重及隻日採食量，以飼糧中色胺酸含量0.26％處理組較0.16%處理組顯著較佳(P < 0.05)，飼料轉換率亦有較佳之趨勢。在菸[生僉]酸添加量方面，隨著飼糧中菸[生僉]酸添加量之增加，隻日增重與隻日採食量均隨之顯著增加(P < 0.05)；而飼料轉換率亦隨著飼糧中菸[生僉]酸添加量之增加而有顯著改善之現象(P < 0.05)。血清尿酸濃度則以0.26%處理組顯著較0.16%處理組為低(P < 0.05)；飼糧菸[生僉]酸添加量0 ppm處理組，血清中尿酸濃度，顯著較其他處理組為高(P < 0.05)；菸[生僉]酸添加量0 ppm處理組與25 ppm處理組，血清中三酸甘油脂濃度顯著較其他處理組為低(P < 0.05)，並以菸[生僉]酸添加量0 ppm處理組為最低。由脛骨性狀顯示，脛骨長度以0.26%色胺酸處理組顯著較0.16%色胺酸處理組者為長(P < 0.05)；而菸[生僉]酸0 ppm 處理組，在脛骨長度、灰分及脛骨重量，顯著低於其他處理組(P < 0.05)。綜上所述，缺乏菸[生僉]酸會導致雛鵝生產性能降低、脛骨粗短症、鱗狀皮膚炎與軟骨發育障礙之發生；畸形腿之發生有隨著飼糧中菸[生僉]酸添加量之增加而降低之趨勢，當飼糧中菸[生僉]酸添加量增加至25 ppm時，可完全防止畸形腿之發生。
The purpose of this experiment was to investigate the effects of different levels of dietary tryptophan and niacin on growth performance, bone and blood characteristics of goslings during 0 to 4 weeks of age. One hundred and twenty similar body weight White Roman goslings, one day of age, were used and were randomly divided into 10 dietary treatments. Each treatmental group contained 2 replicates with 6 goslings. Each group gosling was fed one of ten experimental diets. Ten dietary treaments were 2 tryptophan levels (0.16 and 0.26%) and 5 niacin supplemented levels (0、25、50、75 and 100 ppm), respectively. Goslings were housed in individual cage, the experiment period was 28 days. The goslings were weighed individually once a week, and recoreded the feed intake of each treatmental group. At the end of experiment, each treatmental group was sampled 4 goslings (2♂2♀) which body weight were the group average weight. The goslings were slaughtered, then sampled the blood, liver, abdominal fat and tibia, for the determinations of triglyceride, cholesterol and total lipid of serum；and for tibia weight, length, width, force intensity, relative weight and ash percentage.
The results indicated that the daily weight gain and daily feed intake of goslings in 0.26% tryptophan group was significantly more than 0.16% tryptophan group (P<0.05). Feed conversion rate, 0.26% tryptophan group had a better tendency. When dietary niacin levels increased, daily weight gain, daily feed intake and feed conversion ratio increased significantly (P<0.05). The uric acid concentration of serum in basal diet group was significantly higher than that in the other groups；the uric acid concentration of serum in 0.26% tryptophan group was significantly lower than 0.16% tryptophan group (P<0.05).The concentration of triglyceride in serum of birds fed basal diet was significantly lower than that of birds fed the other diets. In the tibia length, 0.26% tryptophan group was significantly longer than 0.16% tryptophan group (P<0.05). The weight, length, the percentage of ash, in basal diet treatment was significantly lower than those in the other treatments (P<0.05). In conclusion, dietary niacin deficiency led to decrease growth performance, induce tibia perosis, scaly dermatitis and chondrodystrophy; basal diet supplemented with 25 ppm niacin could prevent the occurrence of perosis.