豆粕和土豆蛋白替代饲料中鱼粉对异育银鲫生长及能量收支的影响

利用全能量收支同步测定呼吸仪系统测定了三种不同蛋白源(鱼粉、豆粕、土豆蛋白)饲料对银鲫生长及能量收支各组分的影响。对照饲料全部以鱼粉为蛋白源,另两种饲料中30％的蛋白质分别来自豆粕和土豆蛋白。试验结果表明,银鲫对三种蛋白源的饲料的摄食率,食物转化效率均有显差异,以鱼粉组最高,豆粕其次,土豆蛋白最低。能量收支各组分也均有显差异,能量收支式如下：鱼粉88．1C=13．77F 2．95U 24．1G 41．8R 豆粕 102．3C=17．1F 2．8U 16．4G 55．4R土豆蛋白105．5C=14．9F 1．3U 14．4G 67．4R式中C、F、U、G、R分别代表摄食能、排粪能、排泄能、生长能、代谢能。     

长吻Wei幼鱼的赖氨酸需要量

本文通过以添加结晶氨基酸的半精制饲料饲喂长吻Ｗｅｉ（ＬｅｉｏｃａｓｓｉｓｌｏｇｎｉｒｏｓｔｒｉｓＧｕｎｔｈｅｒ）幼鱼的生长试验来确定春赖氨基酸需要量,试验饲料由鱼粉,玉米蛋白,糊精,明胶等组成,通过添加游离氨基酸达饲料中分别含赖氨酸国１．６４,２．０４,２．４４,２．８４和３．２４％五个水平,结果得出：长吻Ｗｅｉ幼鱼最大生长时对饲料中的赖氨酸的需要量为２．５７％,占饲料蛋白的６．５４％。     

南方鲇的营养学研究:Ⅰ.人工饲料的消化率

采用循环水养殖系统在２７．５℃条件下,用人工饲料持喂养南方鲇（Ｓｉｌｕｒｕｓ ｍｅｒｉｄｉｏｎａｌｉｓ Ｃｈｅｎ）幼鱼６周。以三氧化二铬（Ｃｒ２Ｏ３）为指示物,测定了蛋白质含量为３５％至６０％（变化梯度为５％）的６种等能（２０ｋＪ／ｇ）试验饲料的消化率,实验结果表明,饲料蛋白南水平由３９．８６％升至５５．７３％时,饲料干物质表观消化率（Ｄｄｍ）、蛋白质表观消化率（Ｄｐ）、脂肪表观消化率（Ｄ１）、能     

南方鲇的营养学研究:饲料中大豆蛋白水平对消化率及摄食率的影响

以23.78±0.09g的南方鲇为实验对象,以Cr2O3作为测定饲料消化率的指示物,以大豆蛋白分别替代0%、13%、26%、39%、52%和65%的鱼粉蛋白,配制成6种等氮(粗蛋白48%)、等能(总能20KJ/g)的饲料,用于探讨饲料中大豆蛋白替代鱼粉蛋白的比例对南方鲇消化率及摄食率的影响。实验在27.5±0.02℃水温条件下进行6周,溶氧维持在5mg/L以上,光制为14L∶10D。结果表明,饲料中不同比例的鱼粉蛋白与大豆蛋白对南方鲇的消化率及摄食率均存在显著影响(P<0.05)。其中南方鲇对于物质、蛋白质、脂肪和能量的消化率随着大豆蛋白替代率的提高而逐步下降,当替代量为65%时,其消化率显著低于其余各组(P<0.05)。而南方鲇的摄食率均随着饲料中大豆粉添加量的升高而升高,当大豆蛋白替代鱼粉蛋白超过39%时,摄食率显著高于其余各组(P<0.05)。通过分析认为,消化率是限制南方鲇利用大豆粉的重要因素,而摄食率不是影响其利用率的主要原因。     

罗非鱼对晶体蛋氨酸、包膜蛋氨酸利用的比较研究

为比较罗非鱼对晶体蛋氨酸、包膜蛋氨酸的利用效果, 设计了鱼粉含量为9%的鱼粉饲料、鱼粉含量为0%的无鱼粉饲料(以豆粕等蛋白替代鱼粉), 在无鱼粉饲料基础上分别添加晶体蛋氨酸、包膜蛋氨酸, 使其蛋氨酸含量与鱼粉饲料一致, 共4种饲料, 饲喂平均体重为(1.220.07) g/尾的奥尼罗非鱼(Oreochromis niloticus O. aureus) 8周。结果表明, 各组罗非鱼增重率分别为1642.7%、1250.3%、1362.0%、1451.7%, 饲料系数分别为1.08、1.45、1.30、1.21; 在无鱼粉饲料中添加晶体蛋氨酸、包膜蛋氨酸提高增重率8.9%、16.1% (P0.05), 降低饲料系数10.34%、16.55% (P0.05); 包膜蛋氨酸组较晶体蛋氨酸组具有更高增重率和更低饲料系数(P0.05)。对摄食后不同时间点肝脏和血浆谷草转氨酶(GOT)、谷丙转氨酶(GPT)活性变化的测定表明, 鱼粉饲料组、无鱼粉饲料组肝脏GOT、GPT活性分别在摄食后第2、第4h出现高峰; 晶体蛋氨酸组在摄食后1h出现高峰, 较无鱼粉组提前; 包膜蛋氨酸组在摄食后第5h出现高峰, 较无鱼粉组滞后; 血浆GOT、GPT活性变化趋势与肝脏的基本一致。消化率试验表明, 鱼粉饲料组干物质、粗蛋白质消化率最高, 无鱼粉饲料组最低; 在无鱼粉饲料中添加晶体蛋氨酸、包膜蛋氨酸后, 干物质、粗蛋白质消化率均得到显著提高(P0.05)。上述结果表明, 在蛋氨酸缺乏的实用饲料中补充晶体或包膜蛋氨酸, 均可显著提高罗非鱼生长性能和营养物质消化率, 包膜蛋氨酸较晶体蛋氨酸具有更高的利用效率和更好的促生长效果。       

饲料鱼粉、菜粕比例对异育银鲫生长和饲料利用的影响

通过在饲料中配制不同鱼粉和菜粕比例,探讨利用菜粕蛋白替代鱼粉对异育银鲫（Carssius auratus gibelio）的生长和饲料利用的影响。饲料中菜粕蛋白替代鱼粉蛋白的比例分别为 0、20%、40%、60% 和80%。实验结果表明,当饲料中菜粕蛋白比例高于40%时,异育银鲫的生长显著下降（P0.05）,对摄食率影响不明显（P0.05）。在80%替代水平下,干物质和蛋白质的消化率最低,能量消化率在40%替代水平最低。饲料转化效率在20%蛋白替代后明显下降（P0.05）。蛋白质和能量储积率在40%蛋白替代后明显下降（P0.05）。在40%菜粕蛋白下,鱼体能量和脂肪含量最高。鱼体蛋白质在60% 和80% 菜粕蛋白时最低,脂肪在20% 菜粕蛋白时最高。因此饲料菜粕蛋白的水平不超过20%（干物质含量约17%）不会影响异育银鲫的生长和饲料转化。       

大豆分离蛋白替代鱼粉对虹鳟生长性能及氮磷排泄的影响(英文)

以体重为(4.86±0.02)g的虹鳟稚鱼为实验对象,在室内循环水养殖系统中进行为期90d的生长实验。用1000 U/kg植酸酶预处理大豆分离蛋白,然后以预处理的大豆分离蛋白(Soy protein isolate,SPI)分别替代0、20%、40%、60%、80%和100%的鱼粉蛋白,配制成6种等氮(粗蛋白为44.97%)、等能(粗脂肪为13.42%)的饲料,以评估饲料中鱼粉替代量对虹鳟生长、体组成、消化率及氮磷排泄的影响。90d的养殖实验结果表明,大豆分离蛋白替代鱼粉对虹鳟生长性能和饲料利用率产生显著的影响(P<0.05)。当大豆蛋白替代水平由0增加到40%时,虹鳟的特定生长率(SGR)显著提高,随着饲料中SPI替代水平由40%增加到100%时,虹鳟的SGR显著降低(P<0.05),在S0、S20和S60试验组之间差异不显著(P>0.05)。增重率(WGR)和蛋白质效率(PER)分别在处理组之间的差异关系与特定生长率(SGR)在各组之间的变化趋势相类似;当大豆蛋白分别替代40%时,其饲料系数(FCR)显著低于其他替代组(P<0.05),当替代量超过40%后,随着替代水平的增加,FCR显著增加(P<0.05)。随着替代水平由0升高到100%,磷排泄显著降低,与之相反的是,磷沉积率显著升高。随着替代水平由0升高至40%,氮排泄逐渐降低,当替代水平由40%升高至100%,氮排泄逐渐升高,随着替代水平升高至40%,氮沉积率升高。试验证明,大豆分离蛋白替代量达到40%时,虹鳟的生长及饲料转化率达到最佳,而高比例的SPI对虹鳟的生长性能和饲料效率产生负面影响。     

在高植物蛋白饲料中添加水解鱼蛋白对牙鲆幼鱼的影响

研究采用酶解技术水解太平洋鳕鱼肉, 制备不同分子量组分的两种水解鱼蛋白产品(Fish protein hydrolysate,FPH-A 和FPH-B)。在牙鲆幼鱼高植物蛋白饲料配方中, 以水解鱼蛋白产物1.2%和3.7%两个梯度替代饲料中的鱼粉蛋白, 在室内流水养殖系统中进行了为期60d 的生长实验。研究了高植物蛋白饲料中添加水解鱼蛋白对肉食性鱼类牙鲆(Paralichthys olivaceus)生长性能和饲料利用的影响。结果表明, 添加3.7%的水解鱼蛋白显著促进了牙鲆幼鱼的生长, 特别是添加了富含低分子量组分的水解蛋白产品(FPH-A)后实验鱼的特定生长率最高。各实验处理组牙鲆摄食率没有显著差异。摄食添加3.7% FPH-A 的牙鲆鱼体粗蛋白含量显著高于对照鱼粉组。添加水解鱼蛋白显著提高了牙鲆幼鱼的蛋白质消化率、蛋白质效率和蛋白质沉积率,摄食3.7% FPH-A 实验鱼蛋白质消化率、蛋白质效率和蛋白沉积率最高, 显著高于其他各组。实验表明, 高植物蛋白饲料中添加低分子量组分的水解鱼蛋白可显著提高牙鲆幼鱼的生长和饲料蛋白利用。       

螺旋藻粉替代饲料中鱼粉对异育银鲫幼鱼生长、饲料利用和蛋白沉积的影响

实验以异育银鲫中科3号幼鱼(3.20.5) g为实验对象, 研究螺旋藻粉蛋白替代饲料鱼粉蛋白(0、20%、40%、60%、80%和100%)对鱼摄食、生长、饲料利用和蛋白沉积的影响。实验设计了6种等氮(38%)等脂(10%)等能(16.50 kJ)的饲料, 每处理3个重复。采用室内循环水养殖系统, 表观饱食投喂。实验水温为(283)℃, 实验共持续60d。结果发现:随藻粉替代比例的增加, 鱼摄食率显著上升; 饲料效率则呈显著下降趋势; 特定生长率在20%替代组与鱼粉组无显著差异(P0.05), 其他各替代组均显著低于鱼粉组(P0.05); 蛋白沉积率在20%、60%替代时与鱼粉组无显著差异(P0.05), 其他替代组显著低于鱼粉组(P0.05); 肥满度在各替代组均显著低于鱼粉组(P0.05); 鱼体蛋白随藻粉替代比例的增加呈现先持平后降低的趋势, 鱼体脂肪则呈先降低后升高的变化; 20%、40%和60%替代组全鱼灰分均高于全鱼粉组; 肠道消化酶(胰蛋白酶、脂肪酶和-淀粉酶)在替代组和对照组间均无显著差异(P0.05); 干物质表观消化率随藻粉蛋白替代比例的增加而呈显著上升, 蛋白的表观消化率则呈显著下降趋势, 总磷表观消化率在20%替代时最低, 在100%替代时最高。综合特定生长率和蛋白沉积率情况, 当鲫幼鱼饲料中鱼粉含量约为50%, 且鱼粉为唯一蛋白源时, 螺旋藻粉蛋白可替代饲料中20%鱼粉蛋白。     

大豆低聚糖对牙鲆营养效应的研究：I摄食、生长和代谢酶活性

本试验比较研究了不同蛋白源（鱼粉,FM;大豆分离蛋白,SPI）基础饲料中添加大豆低聚糖（SBOS）对牙鲆（Paralichthysolivaceus）摄食率、生长性能和代谢酶活性的影响。分别以FM、SPI作为主要蛋白源,配制了4种等氮等能饲料。其中,饲料FM、SP1分别以FM、SPI作为主要蛋白源;饲料FMO、SPIO分别在饲料FM、SPI基础上添加10％SBOS（水苏糖：2．61％;棉籽糖：0．61％）。试验表明：①饲料中添加SBOS对牙鲆前两周摄食丰无显著影响（P〉0．05）;而显著降低了整个养殖周期FMO组牙鲆总摄食率,提高了SPIO组牙鲆总摄食牢（P〈0．05）;②FM基础饲料中添加SBOS对牙鲆特定生长率（SGR）、饲料效率（FER）和蛋白质效率（PER）均无显著影响（P〉0．05）,但均呈明显下降趋势;SPI基础饲料中添加SBOS对FER和PER无显著影响,却显著提高了SGR（P〈0．05）;③FM基础饲料中添加SBOS提高了牙鲆血浆谷草转氨酶（AST）、谷丙转氨酶（ALT）、碱性磷酸酶（AKP）、乳酸脱氢酶（LDH）和γ-L-谷氨酰转肽酶（γ-GT）的活性,但仅AST差异显著（P〈0．05）,而对肝脏AST、ALT、AKP、LDH和1．GT活性无显著影响（P〉0．05）;SPI基础饲料中添加SBOS显著提高了血浆ALT和LDH活性,而对AST、AKP和γ-GT活性无显著影响;同时,SPI基础饲料中添加SBOS显著提高了肝脏AST和ALT活性,而对AKP、LDH和γ-GT活性无显著影响;④饲料巾添加SBOS对牙鲆血浆中尿素氮和游离氨基酸浓度均无显著影响。试验结果表明,不同蛋白源基础饲料中添加SBOS表现出不同的生长效应;其中,FM基础饲料中添加SBOS表现出一定的抑制生长效应,而SPI基础饲料中添加SBOS却表现出促生长效应。     

Meat meal in the diet of the early-weaned pig. II. Amino acid supplementation

One hundred and twenty pigs, initially 4–5 kg liveweight, were fed on wheat-based diets supplemented with meat meal and amino acids in two experiments, each of 4 weeks duration.In the first experiment, the supplementation of a normal meat meal diet with lysine and methionine increased the feed intake and weight gains of the pigs by 15 and 18%, respectively. Nitrogen retention was increased by 30%. Tryptophane gave a similar response to lysine and methionine.In the second experiment, a 21% crude protein basal diet was similar to the basal diet of the first experiment but it contained 1.02% lysine and 0.50% methionine plus cystine, compared to 0.90 and 0.51%, respectively, in the first experiment. Lysine and methionine supplementation of the diet did not significantly improve the performance of the pigs in the second experiment, but the supplementation of the diets with 0.08% tryptophane and lysine and methionine increased weight gains and feed intakes and decreased urea content of the blood plasma. The 21% crude protein diet contained 0.15% tryptophane.Increasing the crude protein content of diets from 18 to 24% by increasing their meat meal content increased the daily weight gains from 190 to 276 g.     

不同形式蛋氨酸对建鲤生长性能及血清游离氨基酸含量的影响

为考察不同形式蛋氨酸对建鲤生长的作用效果, 实验以豆粕、鱼粉、棉粕为蛋白源, 配制缺乏蛋氨酸的基础饲料(对照组, 蛋氨酸含量为0.48%), 在基础饲料中分别添加晶体蛋氨酸、微囊蛋氨酸、蛋氨酸羟基类似物(MHA)及蛋氨酸羟基类似物钙盐(MHA-Ca), 使蛋氨酸含量达到0.58%, 获得5个饲料处理组, 饲养平均体重为(8.61.0) g的建鲤(Cyprinus carpio var Jian)8周。结果显示: 各组鱼体增重率分别为343.51%、350.77%、382.80%、384.02%和385.59%; 饲料系数分别为1.58、1.55、1.42、1.42和1.41; 晶体蛋氨酸组鱼体增重率、饲料系数与对照组无显著差异(P0.05), 微囊蛋氨酸组、MHA组、MHA-Ca组增重率较对照组提高11.4%、11.8%、12.2% (P0.05), 饲料系数降低10.1%、10.1%、10.8% (P0.05)。各处理组在肌肉水分、脂肪含量间无显著差异(P0.05), MHA组肌肉粗蛋白含量较晶体蛋氨酸组显著下降, 其他各组间无显著差异(P0.05)。对摄食后不同时间的血清游离氨基酸浓度变化的分析表明, 对照组在摄食后2h或3h达到峰值, 晶体蛋氨酸组、MHA组在摄食后1h达到吸收峰值, 微囊蛋氨酸组在摄食后1h或2h达到峰值, 而MHA-Ca组则在摄食后3h达到峰值。上述结果表明, 在蛋氨酸缺乏的颗粒饲料中补充晶体蛋氨酸, 对建鲤生长性能无改善作用, 而添加微囊蛋氨酸、蛋氨酸羟基类似物、蛋氨酸羟基类似物钙盐则显著提高了鱼体生长性能, 降低饲料系数。       

高比例棉粕饲料中补充蛋氨酸对中华绒螯蟹幼蟹摄食、生长及抗氧化酶活性的影响

以40%棉粕为主的混合蛋白源制成基础饲料, 分别在其中添加0.00%、0.14%、0.28%、0.42%、0.56%蛋氨酸(分别记为0.00%Met、0.14%Met、0.28%Met、0.42%Met和0.56%Met), 配制了5种等氮等能的试验饲料, 以全鱼粉组(64.4%鱼粉)作为对照, 探讨了在高比例棉粕饲料中补充蛋氨酸对中华绒螯蟹幼蟹(0.390.02) g的摄食率、生长率和机体抗氧化酶活性的影响。结果表明: 与全鱼粉对照组相比, 0.42%Met组的增重率、特定生长率和饲料系数均无显著差异(P0.05), 但其显著高于0.00%Met、0.14%Met和0.28%Met组(P0.05); 增重率和特定生长率则显著高于0.56%Met组(P0.05); 从幼蟹的摄食量和蛋白质沉积率来看, 0.42%Met和0.28%Met组的摄食量与对照组相似, 当蛋氨酸的补充量低于0.28%或高于0.42%时, 幼蟹的摄食量均有所下降; 统计表明, 对照组的蛋白质沉积率最高(23.20%), 在各试验组中, 0.28%Met和0.42%Met组之间的蛋白质沉积率无显著差异(P0.05), 但显著高于0.00%Met、0.14%Met和0.56%Met组(P0.05); 分析幼蟹的肠道胰蛋白酶活性, 发现0.42%Met组与对照组之间无显著性差异(P0.05), 但均显著高于其他各试验组(P0.05); 0.28%Met、0.42%Met和0.56%Met处理组的血清丙二醛含量、超氧化物歧化酶活性和谷胱甘肽过氧化物酶活性与对照组无显著差异(P0.05)。结果提示, 在高比例植物蛋白(40%棉粕)的基础饲料中, 补充0.42%Met能够显著提高中华绒螯蟹幼蟹的生长率、消化率和抗氧化酶的活性。       

Nutritive value of rumen contents for monogastric animals

Rumen contents were investigated as a possible feed for farm animals. Although their composition varied to some extent, an average sample contained 21.8% crude protein, 30.3% crude fibre, 6.1% fat and 11.5% ash in the dry matter. Of total crude protein, 73.4% was amino acids. The raw rumen material was dried using the “organic carrier method” by previous mixing with maize meal (3 parts raw rumen contents/1 part maize meal). The product, RM meal (12.5% crude protein, 10.8% crude fibre, 5% fat, 4.9% ash), was used for feeding broiler chicks.The nutritive qualities of dried rumen contents (DRC) were assessed by biological tests on rats. Two levels of DRC (10% and 24%) were included in diets containing blood meal as a protein source and maize (Experiment I). The lower level of DRC (10%) did not reduce the growth rate of young rats (2.4 g/day), but the food consumption was increased. The total body composition of the rats was not changed (55.3% crude protein, 34.1% fat, 9.6% ash). The higher concentration of DRC decreased the growth rates markedly, as well as the apparent digestibility of dry matter and protein, and changed the body composition of rats.The apparent digestibility by rats of rumen protein in a semi-synthetic diet containing 50% DRC (Experiment II) was 44.6% and of dry matter, 56%.The RM meal was given to broiler chicks (0–8 weeks of age) as 23% or 60% of the diet which also contained soya bean meal, blood meal and sunflower meal as protein supplements (Experiment III). The chicks consumed all diets readily. The diet containing 23% RM meal (corresponding to 6.4% DRC) supported a better performance than the control diet. The larger amount of RM meal (corresponding to 17% DRC) reduced the final body weights of chicks.     

Optimum dietary crude protein level for finishing Awassi lambs

Awassi is a multi-purpose sheep breed. Awassi lambs being finished are usually offered an 18% crude protein (CP) diet. The growth rate of Awassi lambs is lower than other meat breeds. Therefore, this high content of dietary CP is questionable. The objective of this study was to estimate the optimum CP level for finishing Awassi lambs. Fifty male Awassi lambs (23.0±1.2 kg) were fed five high concentrate isocaloric diets (10 lambs per diet) that contained 10, 12, 14, 16, and 18% CP in a totally mixed diets for 9 weeks using a completely randomized design. Lambs were fed twice daily, and feed offered and feed refusals recorded for each feeding. Individual lamb intakes were calculated using daily feed offered and feed refused averaged over the interval of the experiment. Digestibility estimates were measured by total fecal collection. Lambs fed diets that contained 10, 12, and 14% CP gained less weight than those fed the 16 and 18% CP diets (P<0.05). Dry matter and CP intakes increased (P<0.05) with increasing levels of dietary CP. No difference (P>0.10) was observed in feed-to-gain ratio between diets except for the diet that contained 10% CP (P<0.05) which had a lower ratio. Organic matter and CP digestibility were lowest in lambs fed the 10% CP diet. Results suggest that the optimum CP concentration is 16% and that any increase above this level will not result in any improvement in production.     

饲料中添加胆汁酸对牛蛙生长性能、体组成和营养物质表观消化率的影响

试验研究了饲料中添加胆汁酸对牛蛙Rana (Lithobates) catesbeiana生长性能、体成分和营养物质表观消化率的影响。基础饲料以鱼粉、豆粕为主要蛋白源, 棕榈油为主要脂肪源, 在基础饲料中分别添加0、100、200和300 mg/kg的胆汁酸(含量99.1%)制作4种等氮等能的试验饲料。试验将144只牛蛙初始体重(75.014.23) g随机分为4组, 每组3个重复, 每个重复12只牛蛙, 进行为期8周的生长试验。结果显示: 各试验组牛蛙成活率和摄食率差异不显著(P0.05)。200 mg/kg胆汁酸添加组牛蛙的增重率、特定生长率、饲料效率、蛋白质效率和氮保留率显著高于对照组(P0.05)。在饲料中添加胆汁酸显著降低了牛蛙脏体指数和全体的脂肪含量(P0.05), 但不影响肌肉粗脂肪以及全体和肌肉水分、粗蛋白、粗灰分含量(P0.05)。各处理组间血清总胆固醇、甘油三酯、高密度脂蛋白胆固醇和低密度脂蛋白胆固醇浓度均无显著变化(P0.05), 血清尿素氮含量随着饲料中胆汁酸添加量的增加而降低, 添加300 mg/kg胆汁酸组牛蛙血清尿素氮含量显著低于对照组(P0.05)。血糖水平则随着胆汁酸添加量的增加而先降低后升高, 其中100 mg/kg胆汁酸添加组牛蛙血糖水平最低(P0.05)。100 mg/kg胆汁酸添加组牛蛙肠道脂肪酶活力显著高于对照组和300 mg/kg胆汁酸添加组(P0.05), 与200 mg/kg胆汁酸添加组之间差异不显著(P0.05), 蛋白酶活力与脂肪酶活力有相似的变化趋势, 而淀粉酶活力未受胆汁酸添加水平影响。各处理组饲料营养物质的表观消化率随饲料中胆汁酸添加量的增加而先升高后降低, 其中饲料添加200 mg/kg胆汁酸显著增加了牛蛙对饲料营养物质的表观消化率(P0.05)。结果表明: 在饲料中添加适量的胆汁酸能提高牛蛙对饲料的消化率, 提高饲料效率, 从而促进牛蛙的生长, 同时可促进蛙体脂肪代谢, 降低机体脂肪沉积, 提高牛蛙可食部分比例。根据本试验结果, 建议牛蛙饲料中胆汁酸添加水平为200 mg/kg。       

Apparent digestibilities and growth experiments with tilapia (Oreochromis niloticus) fed soybean meal, cottonseed meal and sunflower seed meal

Apparent digestibility and growth experiments with three oil seed by-products, soybean meal, cottonseed meal, and sunflower seed meal, were conducted using tilapia ( Oreochromis niloticus ) with an initial average body weight of 93 ± 5 g and 64 ± 1 g, respectively. The diets were formulated on an isonitrogeneous and isoenergetic basis. During the experimental period the fish were fed 1% and 1.5% of their metabolic body weight (kg^0.8) daily in the digestibility experiment and the growth experiment, respectively. Water temperature was maintained at 26.5 ± 1°C. Apparent digestibilities of the components and the diets were determined using an indirect method, i.e. with HCl-insoluble ash as an indicator. Faeces collection was carried out using a sedimentation technique.
Results of the apparent digestibilities showed that the crude protein, crude fat, as well as the gross energy digestibilities of soybean meal (93.0%, 94.6%, and 77.2%, respectively), were better than those of cottonseed meal (79.4%, 83.2%, and 57.9%, respectively) and sunflower seed meal (89.8%, 82.9%, and 49.3%, respectively). With the exception of the crude protein digestibility, nutrient and gross energy digestibilities of the cottonseed meal were found to be better than that of sunflower seed meal.
Growth experiment results indicated that soybean meal diet groups had inferior growth performance and feed conversion in comparison to the fishmeal control diet or the other test diets at an inclusion level of 32% of the digestible protein. Fish fed cottonseed meal diet and sunflower seed meal diet showed a relatively better, but not significantly different performance than did the fishmeal control diet. Supplementation diets with lysine and methionine did not enhance fish performance.     

Effect of cellulase,phytase and pectinase supplementation on growth performance and nutrient digestibility of rainbow trout (Oncorhynchus mykiss,Walbaum 1792) fry fed diets containing canola meal

This experiment was conducted to evaluate the effects of supplementing exogenous enzymes on growth, feed conversion ratio (FCR) and apparent nutrient digestibility in rainbow trout (Oncorhynchus mykiss) fry diets containing 32% canola meal. Five experimental diets (including a control diet containing no enzymes) were prepared as isonitrogenous (44% crude protein) and isocaloric (4000 kcal DE kg¹). The four other diets contained either cellulase, phytase, pectinase or an enzyme mix (a mixture of cellulase, phytase and pectinase in the same ratio). The feeding trial was conducted in triplicate for 12 weeks in 15 tanks (100‐L). At the beginning of the experiment 20 rainbow trout fry (initial weight 1.23 g) were stocked into each tank. Mean water temperature in the rearing tanks was 11°C and water flow in each tank was 6 L min^?1. At the end of the experiment the growth parameters and FCR displayed no significant differences in enzyme supplementation (P > 0.05). In addition, no differences were observed in dry matter, protein, or lipid digestibility with enzyme supplementation (P > 0.05). The results of this study showed that the addition of pectinase, phytase, cellulase or an enzyme mix to a diet containing 32% canola meal had no effect on growth, feed efficiency or dry matter, protein, or lipid digestibility in rainbow trout fry.     

Use of soybean flour (dehulled, solvent-extracted soybean) as a fish meal substitute in practical diets for African catfish, Clarias gariepinus (Burchell 1822): growth, feed utilization and digestibility

Growth and digestibility trials were conducted using African catfish, Clarias gariepinus (Burchell 1822): (1) to obtain apparent digestibility coefficient (ADC) values for capelin fish meal, soybean flour and corn meal; (2) to formulate diets based on ADC values of the protein feedstuffs; and (3) to evaluate the effects of replacing 25%, 50% and 75% of fish meal in control diets with soybean flour on growth, feed utilization efficiency and carcass composition. Supplemental methionine was added to the diet formulation in which soybean flour replaced 75% of the diet. Diets were formulated (400 g digestible protein kg⁻¹ and 15 kJ digestible energy g⁻¹ dry diet) and fed to catfish fingerlings (13.1 ± 0.5 g) to apparent satiation twice daily for 70 days. The protein and energy digestibilities of fish meal and soybean flour were high (>90% and >80%, respectively; P < 0.05). At 75% fish meal replacement with soybean flour (without methionine supplementation), growth and feed utilization efficiency indicators were depressed compared with other diet treatments which had a similar (P > 0.05) growth and feed utilization efficiency to those fed the control diet. The carcass compositions of catfish in all diets were similar (P > 0.05) and the liver histology of catfish fed any of the diets showed no alterations. The results obtained indicate that 50% of fish meal protein in practical catfish diets can be replaced with soybean flour and that catfish can effectively utilize supplemental methionine, thereby allowing up to 75% of the dietary fish meal protein to be replaced by soybean flour.