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投喂频率对南美白对虾(Penaeus vannamei Boone)生长、饲料利用及虾体组成影响的初步研究 总被引：4，自引：0，他引：4
本实验选用商品饲料饲养平均初体重为0．09g的南美白对虾，经过30d的生长实验，研究不同投喂频率对南美白对虾生长、成活以及饲料利用的影响。结果表明，随着投喂频率由3次／天增加到5次／天，南美白对虾的增重率、特定生长率和蛋白质效率显著提高，而饲料系数则显著降低，但当投喂频率由5次／天增加到7次／天时，南美白对虾增重率、特定生长率和蛋白质效率并无显著提高。对对虾全虾体主要组成成分的分析表明南美白对虾体主要组成成分并不受投喂频率增加的影响。 相似文献
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Seasonal and sexual variations as well as the effect of dry feed supplement on total drinking water intake and its utilization were observed in mithun （Bosfrontalis） - a semi-wild animal found in North Eastern Hill Region （NEHR） of India. In a completely randomized design, twelve adult mithuns （B. frontalis） as per their sex and body weight were assigned in two different rearing systems （free grazing and free grazing with dry concentrate feed supplementation）, and ten growing male mithuns as per their body weight assigned in two different levels of dry concentrate feed supplementation （1.o kg and 2.0 kg dry concentrate feeds on green forage based diet） and in two different seasons （summer and winter）. It was observed that the environmental temperature had a significant effect on drinking water intake by mithuns. Drinking water consumption （per unit of body weight） was significantly （P 〈 0.05） higher in summer than in winter. Supplementation of concentrate feed on free grazing animals resulted in increase in water consumption. Total water consumption （drinking as well as performed water） was found to be 15.18 litres per 100 kg body weight by growing mithun. Feed dry matter and digestible nutrient intakes by growing mithun were observed to be increased with the increase of supplementation of dry concentrate feed. Roughage to concentrate ratio did not affect the nutrient digestibility. Mithun calves drank an average of 4.30 litres water for each kg of dry matter intake. Metabolic water was significantly （P〈0.01） increased with the increase of supplementation of concentrate feed whereas water turn over, which depends upon the body weight of the animals, did not differ significantly on offering of lower or higher level of dry feed. Faecal water loss of growing mithun was decreased with the increase in intake of concentrate feed and was estimated to be 33 - 46 % of total water intake. Excretion of water through faeces of mithun was about 3.8 % of body weight. It could, there 相似文献
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温度对奥尼罗非鱼仔稚鱼生长、饲料利用和消化酶活力的影响 总被引：1，自引：0，他引：1
研究了温度22、25、28、31和34℃下奥尼罗非鱼(Oreochromis niloticus×O.aureus)仔稚鱼生长、饲料利用和消化酶活力。结果表明:1)不同温度对奥尼罗非鱼仔稚鱼生长有显著影响(P<0.05),温度为31℃时,仔稚鱼生长速度和绝对增重率最高,分别为0.08cm/d和0.035g/d;温度为22℃时最低,仅0.06cm/d和0.020g/d。2)饲料系数在28℃时最低,仅1.90;22和34℃时较高,达2.14和2.17,各组差异显著(P<0.05)。3)在仔稚鱼发育和存活率上,当温度在22～34℃时,温度越高,仔稚鱼发育越好;各组仔稚鱼的存活率介于93.7%～94.7%,差异不显著(P>0.05)。4)在消化酶活力上,胃蛋白酶、胰蛋白酶和淀粉酶活力随温度升高而升高,均在34℃时活力最高;脂肪酶活力在31℃时达到最高,22℃时活力最低。 相似文献
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Seasonal and sexual variations as well as the effect of dry feed supplement on total drinking water intake and its utilization were observed in mithun (Bos frontalis)-a semi-wild animal found in North Eastern Hill Region (NEHR) of India. In a completely randomized design, twelve adult mithuns (B. frontalis) as per their sex and body weight were assigned in two different rearing systems (free grazing and free grazing with dry concentrate feed supplementation), and ten growing male mithuns as per their body weight assigned in two different levels of dry concentrate feed supplementation (1.0 kg and 2.0 kg dry concentrate feeds on green forage based diet) and in two different seasons (summer and winter). It was observed that the environmental temperature had a significant effect on drinking water intake by mithuns. Drinking water consumption (per unit of body weight) was significantly (P < 0.05) higher in summer than in winter. Supplementation of concentrate feed on free grazing animals resulted in increase in water consumption. Total water consumption (drinking as well as performed water) was found to be 15.18 litres per 100 kg body weight by growing mithun. Feed dry matter and digestible nutrient intakes by growing mithun were observed to be increased with the increase of supplementation of dry concentrate feed. Roughage to concentrate ratio did not affect the nutrient digestibility. Mithun calves drank an average of 4.30 litres water for each kg of dry matter intake. Metabolic water was significantly (P<0.01) increased with the increase of supplementation of concentrate feed whereas water turn over, which depends upon the body weight of the animals, did not differ significantly on offering of lower or higher level of dry feed. Faecal water loss of growing mithun was decreased with the increase in intake of concentrate feed and was estimated to be 33～46% of total water intake. Excretion of water through faeces of mithun was about 3.8% of body weight. It could, therefore, be inferred that water intake by mithun varied with seasons, rearing systems and dry feed consumption. As far as the water nutrition is concerned, it is needed to give an attention while feeding mithun in summer with dry feed supplementation under semi-intensive system of rearing. 相似文献
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不同饲料蛋白水平下L-肉碱对新吉富品系尼罗罗非鱼生长和饲料利用的影响 总被引：1，自引：1，他引：0
研究了三个蛋白水平(22%、25%、28%)和五个L-肉碱水平(0、200、400、600、800mg/kg)下尼罗罗非鱼生长和饲料利用率。结果表明,随着饲料中蛋白水平的提高,罗非鱼幼鱼的终体重、增重率(WGR)和特定生长率(SGR)呈上升趋势,而饲料系数(FCR)和蛋白质效率(PER)均随饲料蛋白水平的升高而显著下降(P<0.05);同等蛋白水平下,终体重、WGR和SGR均在L-肉碱添加量为200mg/kg时最高,不添加L-肉碱组最小;在添加400mg/kgL-肉碱时FCR最小,而PER最大,与不添加L-肉碱组比较,差异均显著(P<0.05)。说明饲料中蛋白含量和L-肉碱添加量能显著影响罗非鱼幼鱼的生长和饲料利用,而外源性L-肉碱可明显促进罗非鱼生长,提高饲料转化效率。 相似文献
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为研究投喂策略对多纹钱蝶鱼(Selenotoca multifasciata)幼鱼生长的影响,实验选取初始湿体质量为1.19±0.35 g的多纹钱蝶鱼幼鱼进行养殖,实验为期60 d。1)投喂频率实验:实验设计4组,分别为F1(8:00投喂1次), F2(8:00、20:00投喂2次), F3(8:00、14:00、20:00投喂3次), F4(8:00、12:00、16:00、20:00投喂4次),每组随机放80尾实验鱼,各2个平行,观察多纹钱蝶鱼幼鱼生长及饲料利用情况,结果显示:各组终末湿体质量、增重率、特定生长率、摄食率、肥满度均随投喂频率增加呈先上升后降低的趋势,F2与F3无显著差异(P>0.05),F1与F4无显著差异(P>0.05)。F4组存活率与其他组差异显著(P<0.05), F1组增重率显著低于其他组(P<0.05),特定生长率最高的F2组与F1、F4组差异显著(P<0.05),最低的F1组与其他组差异均显著(P<0.05),4种投喂频率对摄食率、肥满度、饲料系数及蛋白质效率没有显著影响(P>0.05)。2)投喂水平实验:实验设... 相似文献
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An 8-week feeding experiment was conducted in an indoor recirculation seawater system to investigate the effects of partial replacement of dietary fishmeal with proteins from five sources on the growth performance and feed utilization of Sebastes schlegeli. Six isonitrogenous and isoenergetic diets were formulated using fishmeal (FM, the control) as sole protein source, or proteins from five sources including poultry by-product meal (PBM), meat and bone meal (MBM), soybean meal (SBM), cottonseed meal (CSM) and canola meal (CNM). Fifteen percent of the crude protein provided by fish meal was replaced, respectively. The results showed that the differences in specific growth rate (SGR) and survival rate (SR) among fish fed PBM, MBM, SBM, CSM and whole FM diets were not significant. However, SGR and SR of fish fed CNM diet was significantly lower than that of other treatments. Feeding rate, feed conversion, nutrient retention showed similar patterns to that of growth. Fish fed CSM and CNM showed significantly lower apparent digestibility coefficient (ADC) of dry matter and gross energy than those fed others while fish fed CNM showed lower ADC of crude protein than those fed others (P<0.05). These results suggested that it was feasible to substitute 15% dietary protein provided by fishmeal with PBM, MBM, SBM and CSM, respectively, but not with CNM as the replacement with CNM reduced fish growth and feed utilization. 相似文献
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