投喂频率对鳡幼鱼摄食及生长的影响

研究了不同投喂频率(1次/d,2次/d,3次/d,4次/d)对鳡(Elopichthys bambusa)幼鱼摄食及生长的影响,试验持续30 d。结果显示:投喂频率从1次/d增加到4次/d,鳡幼鱼的摄食率逐步提高,1次/d组的摄食率显著低于其他组(P<0.05);体重增加率、特定生长率有不同程度增高,在3次/d时达到最高;饲料转化率逐次下降,1次/d组显著高于其他组(P<0.05)。随着投喂频率增加,实验各组组内个体体重差异显著下降,鳡的规格趋于整齐,组间每日摄食表现也各不相同。试验表明:鳡的生长受投喂频率的影响,每天投喂3次是鳡养殖的最佳投喂频率。     

不同饥饿时间对白斑狗鱼恢复投喂期间生长性能的影响

在水温22~26℃条件下,研究了在不同饥饿时间处理后再投喂对白斑狗鱼(Esox lucius)生长性能的影响,试验设置饥饿14、21、28、35、42 d组和正常投喂对照组,各组饥饿结束后恢复正常投饵,在投喂后以7 d为一个生长阶段,比较各处理组的增重率、特定生长率、摄食率、饲料系数,试验周期为56 d。结果显示,随着饥饿时间的延长,白斑狗鱼的总体重损失率呈逐渐升高的趋势,而各饥饿阶段体重损失率呈下降的趋势;各饥饿处理组恢复投喂后的增重率和特定生长率均显著高于对照组(P<0.05),且随饥饿时间的延长而逐渐升高,但在恢复投喂后的第35天,S14组(饥饿14 d组)与对照组无显著性差异(P>0.05);各饥饿处理组恢复投喂后的摄食率随饥饿时间的延长而显著性升高(P<0.05);饵料系数随饥饿时间的延长而逐渐下降,其中在第14天时,S42组(饥饿42 d组)的饵料系数显著高于其他饥饿处理组(P<0.05),与对照组无显著性差异(P>0.05)。在同一饥饿处理组,随着投喂时间的延长,增重率、特定生长率和摄食率均呈显著性下降的趋势(P<0.05),饵料系数呈升高的趋势,其中S14组在第35天时恢复到对照组水平。结果表明:摄食率升高和饵料系数下降是饥饿再投喂白斑狗鱼增重率显著上升的原因,且这种生长倾向随着恢复投喂时间的延长而不断减弱。     

投喂频率对福瑞鲤幼鱼摄食与生长的影响

研究不同投喂频率(1次/d,2次/d,3次/d,4次/d)对福瑞鲤(FFRC strain common carp)幼鱼摄食与生长的影响,试验周期为30 d。结果显示:当投喂频率从1次/d增加到4次/d时,福瑞鲤幼鱼的摄食率逐步提高,1次/d组的摄食率显著低于其他组(P0.05);体重增长率、体长增长率和特定生长率随投喂频率的增加均有不同程度提高,在4次/d时达到最高;饲料转化率逐步升高,1次/d组显著低于其他组(P0.05)。各试验组福瑞鲤幼鱼的个体体重/体长差异随着投喂频率的增加而先升后降,最终幼鱼的规格趋于一致。综合本试验结果,投喂频率对福瑞鲤幼鱼的摄食与生长存在显著影响,在4次/d的投喂频率下其摄食水平、生长性能、饲料转化效率及大小分化差异系数等均表现出较好状态。     

投喂频率对池塘循环水养殖大口黑鲈消化酶、组织结构及脂代谢酶基因表达的影响

为研究池塘工程化循环水养殖模式下投喂频率(2 次/d、3 次/d、4 次/d)对大口黑鲈(Micropterus salmoides)体成分、肠道消化和肝脏组织结构及脂蛋白酯酶(LPL)和肝脂酶(HL)基因相对表达丰度的影响, 选用平均体重为 (5.0±0.4) g 的大口黑鲈为研究对象, 在池塘工程循环水养殖系统中进行为期 120 d 的养殖实验。结果表明, 投喂频率对鱼体全鱼的粗脂肪和灰分含量影响显著(P<0.05); 投喂频率 2 次/d 组的灰分含量显著高于其他两组, 而 2 次/d 组体脂肪含量低于投喂 3 次/d、4 次/d 组, 体水分和粗蛋白含量均不受投喂频率的影响(P>0.05); 投喂频率 2 次/d 组肠道淀粉酶和脂肪酶活性显著高于 4 次/d 投喂组(P<0.05); 投喂频率对大口黑鲈肠道绒毛高度和宽度影响不显著 (P>0.05), 4 次/d 组肠道绒毛排列整齐度下降且肌层厚度显著低于 2 次/d 和 3 次/d 组(P<0.05)。肝脏组织学显示, 投喂频率越高肝脏脂肪堆积加重, 相对于 2 次/d 和 3 次/d 组, 4 次/d 组肝细胞偏移、空泡化的现象较明显。在第 60 天和 90 天, 2 次/d 组 LPL 基因相对表达量显著高于 4 次/d 组(P<0.05); 而在第 120 天时, LPL 的相对表达量在各组间差异不显著(P>0.05)。2 次/d 组 HL 基因相对表达量显著高于 4 次/d 组(P<0.05)。综合分析, 在饱饲投喂条件下, 池塘循环水养殖大口黑鲈的适宜投喂频率为 2 次/d。     

投喂频率对绿鳍马面鲀幼鱼生长和肌肉品质的影响

为研究不同投喂频率对绿鳍马面鲀幼鱼生长性能和肌肉品质的影响,在室内循环水养殖系统中,采用人工配合饲料,以1次/d、2次/d、3次/d、4次/d等4种投喂频率,对体质量(13.8±0.83)g的绿鳍马面鲀幼鱼进行了饲养试验,试验时长为42 d。结果显示,随着投喂频率增加,绿鳍马面鲀幼鱼的终末体质量呈逐渐升高的趋势,特定生长率呈先升后降的变化趋势,其中3次/d组幼鱼的特定生长率最高,显著高于1次/d组(P<0.05);饲料系数也随着投喂频率的增加而升高,3次/d组的饲料系数显著高于1次/d组(P<0.05),4次/d组的饲料系数显著高于1次/d组和2次/d组(P<0.05);肌肉品质方面,4次/d组幼鱼的肌肉粗脂肪含量显著高于1次/d组(P<0.05),不同投喂频率组间肌肉粗蛋白质含量和灰分含量无显著性差异(P<0.05)。综合考虑生长性能和肌肉品质指标,绿鳍马面鲀幼鱼适宜的投喂频率为日投3次。     

不同循环饥饿投喂模式对许氏平鲉生长和体成分的影响

为探究不同循环饥饿投喂模式下许氏平鲉的补偿生长和体成分的变化，分别采用每日投喂(对照组)、饥饿2 d投喂1 d、饥饿2 d投喂2 d、饥饿2 d投喂3 d、饥饿2 d投喂4 d和饥饿2 d投喂5 d的循环饥饿投喂模式，对初始体长(10.25±0.74) cm、体质量(16.77±2.72) g的许氏平鲉幼鱼进行为期67 d的养殖试验。试验结果显示：饥饿2 d投喂5 d试验组的终末体质量、质量增加率、特定生长率均最高，表现为超补偿生长；饥饿2 d投喂4 d组的终末体质量、质量增加率和特定生长率与对照组差异不显著(P>0.05),表现为完全补偿生长；饥饿2 d投喂1 d、饥饿2 d投喂2 d和饥饿2 d投喂3 d试验组的终末体质量、质量增加率和特定生长率均显著低于对照组(P<0.05),表现为不能补偿生长。各组间的饲料效率、肝体指数和肥满度差异不显著(P>0.05),但对照组的脏体指数显著高于循环饥饿投喂组(P<0.05)。与对照组相比，循环饥饿投喂组(除饥饿2 d投喂5 d试验组外)的鱼体粗脂肪含量显著降低(P<0.05),粗蛋白质和灰分含量各组间差异不显著...     

投喂频率对点篮子鱼生长性能影响

以初始平均体重(114.71±3.631)g、体长(15.70±0.352) cm的点篮子鱼为研究对象,探讨不同的投喂频率对其生长性能及体成分的影响.结果表明,投喂频率对点篮子鱼的存活率没有显著影响(P＞0.05),试验期间各个试验组存活率均为100％.而投喂频率对点篮子鱼的特定生长率(SGR)、日均增重(DWG)和增重率(WG)有显著影响(P＜0.05).每天投喂1次(F1)到4次组(F4)的点篮子鱼的SGR、DWG和WG随投喂频率的增加而显著性升高,而每天投喂5次组(F5)的SGR、DWG和WG显著低于F4组.随着投喂频率的提高,点篮子鱼的摄食率(FR)逐渐上升.饵料系数(FCR)与投喂频率呈正相关.鱼体水分和灰分含量随着投喂频率的增加而下降,F1到F4组间有显著性差异(P＜0.05),F4到F5无显著性差异.各试验组鱼体蛋白质含量无显著变化,而脂肪含量随投喂频率增加显著增加(F1到F4组间差异显著(P＜0.05),F4与F5无差异).综合本试验点篮子鱼的生长性能、饲料转化率和体成分变化,认为人工养殖点篮子鱼的最适投喂频率为4次/d.     

斜带石斑鱼种苗转饵模式研究

对36日龄平均体质量(0.21±0.01)g的斜带石斑鱼种苗的转饵模式进行研究。设计5种转饵模式:转饵1组前10d投喂生物饵料,然后转投配合饲料;转饵2、转饵3和转饵4组前10d进行联合投喂(转饵2:25%配合饲料+75%生物饵料;转饵3:50%配合饲料+50%生物饵料;转饵4:75%配合饲料+25%生物饵料),然后转投配合饲料;转饵5组直接投喂配合饲料;转饵试验至种苗60日龄结束。试验结果表明,由于鱼体长度变异系数显著高于其他各组(P0.05),转饵4组试验鱼死亡率最高,而其他各组之间差异不显著(P0.05);试验结束时,转饵1组试验鱼体质量和质量增加率最低,显著低于其他各组(P0.05),而转饵2组又显著低于转饵4和转饵5组(P0.05);转饵1组种苗36—45日龄的特定生长率显著低于其他各组(P0.05),而46—60日龄的特定生长率显著高于其他各组(P0.05)。转饵试验结束后,各组种苗全鱼水分和粗蛋白含量差异不显著(P0.05),转饵5组种苗全鱼粗脂肪含量显著低于其他各组(P0.05)。综合比较各项指标,转饵3的模式种苗质量增加率较高而死亡率较低,是本研究中效果较好的转饵模式。     

高温和投饵对海蜇螅状幼体生长和足囊繁殖的影响

以海蜇新生螅状幼体为研究对象，采用实验生态学方法研究3种高温(室内恒温、夏季常温、夏季高温)、3种饵料投喂频率(无饵料投喂、每7 d投喂1次、每2 d投喂1次)及其交互作用对海蜇螅状幼体的死亡率、个体生长和足囊繁殖的影响，试验持续45 d。试验结果显示：高温条件下，饵料投喂频率显著影响海蜇螅状幼体的死亡率(P<0.05);而高温、饵料投喂频率及两者交互作用均显著影响海蜇螅状幼体的相对生长率(P<0.05);各高温组中螅状幼体生成的足囊数均随饵料投喂频率的增加而增多；足囊萌发率最多出现在夏季常温-每7 d投喂1次组，平均为34.34%;饵料投喂频率对海蜇螅状幼体生成足囊数及足囊萌发率影响显著(P<0.05),高温及两者交互作用对海蜇螅状幼体生成足囊数及足囊萌发率影响均不显著(P>0.05)。试验结果表明，尽管高温条件下海蜇螅状幼体死亡率高，但存活的螅状幼体足囊繁殖速度快，足囊繁殖速度随温度的升高而加快可能是螅状幼体应对高温死亡率增加的一种繁殖策略。试验结果可为提高海蜇育苗技术和准确预报苗种产量提供科学依据。     

锦鲤幼鱼循环饥饿后的补偿生长和体成分变化

为研究体长(10.63±0.20)cm、体重(17.63±0.72)g锦鲤(Cryprinus carpiod)幼鱼循环饥饿后的补偿生长和体成分变化,试验设5个组,分别为正常投喂和4个循环饥饿投喂组,其中循环饥饿投喂组投喂方式分别为:饥饿1 d后投喂3 d、饥饿1 d后投喂5 d、饥饿2 d后投喂3 d、饥饿2 d后投喂5 d,试验水温为(27.0±1.0)℃,试验周期为40 d。试验结果表明:循环饥饿1 d后投喂的特定生长率、摄食率均显著高于正常投喂的(P0.05),但末均长、末均重、总摄食量、相对增重率和饲料利用率的差异均不显著(P0.05),表现为完全补偿生长,推测其补偿生长应是通过提高摄食率来实现的;循环饥饿2d后投喂的末均长、末均重、总摄食量、特定生长率、相对增重率均显著低于正常投喂的(P0.05),而摄食率、饲料利用率的差异均不显著(P0.05),表现为不能补偿生长,但是否对其生理机能造成伤害有待于进一步研究确定;4个循环饥饿投喂组的鱼体粗蛋白和粗脂肪含量较正常投喂组有所降低,而水分和灰分含量有所升高。因此,循环饥饿1 d后投喂3 d的实际投喂时间较短,且为完全补偿生长,是最佳的循环饥饿投喂模式。     

投喂频率对尼罗系吉富罗非鱼幼鱼胃排空、生长性能和体组成的影响

通过胃排空试验与养殖试验研究了不同投喂频率对尼罗系吉富罗非鱼幼鱼的胃排空、生长性能以及体组成的影响.在试验开始时,观测尼罗系吉富罗非鱼幼鱼的胃内饲料排空情况,胃排空试验结果表明,胃排空率的最佳描述为平方根函数,胃内饲料在饱食投喂后15 h左右完全排空,达到投喂前水平,80％胃排空为9h,也就是投喂后大约9h恢复食欲.360尾试验鱼(初始体质量3.72 g)以不同的投喂频率(1d4次、1d3次、1d2次、2d4次、2d3次、2d2次)分组,每组设立3个平行组,随机养殖于18个网箱中,每箱养殖20尾鱼,按饱食量投饲膨化饲料.养殖期为6周.尼罗系吉富罗非鱼幼鱼在投喂频率为1d4次、1d3次和1d2次时特定生长率和饲料效率显著高于投喂频率为2d4次、2d3次和2d2次时(P＜0.05)；投喂频率为1d2次、2d4次、2d3次和2d2次时其摄食量显著低于1d4次和1d3次时(P＜0.05).随着投喂频率降低,鱼体水分含量逐步上升,脂肪和蛋白质含量逐步下降,其中1d4次、1d3次组鱼与2d2次组鱼有显著性差异(P＜0.05).各投喂频率组间的肝体指数无显著性差异(P＞0.05).3.7～48.0 g尼罗系吉富罗非鱼幼鱼的适宜投喂频率为1d2次,较2d2次、2d3次和2d4次时明显提高了生长速度和饲料效率,较1d3次、1d4次摄食量显著降低.2种试验结果较为一致.     

Effect of partial replacement of fish meal with soybean meal and feeding frequency on growth,feed utilization and body composition of juvenile Chinese sucker,Myxocyprinus asiaticus (Bleeker)

A factorial (2 × 4) feeding trial was conducted to investigate the effects of feeding frequency and partial replacement of fish meal (FM) with soybean meal (SBM) on the growth performance, feed utilization and body proximate composition of juvenile Chinese sucker. Two feed types including replacement of 30% FM (diet 1) with SBM (diet 2) were used. Triplicate groups of fish (average weight, 11.80 ± 0.19 g) were fed each feed type to visual satiation at four meals per day, three meals per day, two meals per day and one meal per day for 8 weeks. At the end of the feeding trial, the survival of fish was not significantly different among the treatments. Weight gain was affected by the feeding frequency. The highest weight gain was observed in fish fed with diet 1 at three meals per day. There existed a significant difference in daily feed intake (DFI), daily protein intake (DPI), feed conversion ratio (FCR) and protein efficiency ratio (PER) when the feeding frequency was increased from one or two to three or four meals per day (P < 0.001), but not by the feed types. For both two feed types, the highest DFI and DPI were observed at three meals per day. The highest PER was gained at four meals per day, while FCR was the least. The body proximate composition of fish was altered by feeding frequency. The crude lipid content increased with the increase in feeding frequency. Essential amino acids (EAAs) content showed no significant differences among different treatments. The present findings suggest that three feedings per day at visual satiation may be sufficient for the maximal growth performance of Chinese sucker grown from 11 to 45 g. Results also indicate that about 30% of FM protein can be replaced by SBM protein in Chinese sucker diets without adversely affecting growth.     

Effect of photoperiod and feeding frequency on growth and feed utilization of fingerlings Persian sturgeon (Acipenser persicus)

The effects of photoperiod (12L:12D and 18L:6D) and feeding frequency (three, four and five evenly spaced daily feedings) of 10% biomass per day during light hours on growth and stress response of Persian sturgeon (Acipenser persicus) fingerlings were evaluated. The interaction between photoperiod and feeding frequency was not significant (P>0.05). Faster growth was observed in fish exposed to an 18L:6D photoperiod (P<0.01). The feed conversion efficiency (FCE) was also better with an 18L:6D photoperiod (P<0.05). Fish fed four and five meals per day grew similarly (P>0.05) and faster than when fed only three meals (P<0.01). The FCE with four or five meals per day was better than with three meals (P<0.05). At harvest, the proximate composition was similar in all treatments (P>0.05). Stress indicators (cortisol, glucose and haematocrit) did not differ between photoperiods (P<0.05). The results showed that 0.9–8.0 g Persian sturgeon fingerlings should be reared with an 18L:6D photoperiod and fed four times per day to obtain good growth and FCE.     

Effects of Feeding Rate and Feeding Frequency on Survival, Growth, and Body Composition of Ayu Post-Larvae Plecoglossus altivelis

The effects of feeding rate and feeding frequency on survival, growth and body composition of ayu post‐larvae (0.15 g in body weight and 3.5 cm in total length) were investigated in this study. A factorial experimental design of two feeding rates (3 and 6% of body weight of fish per meal) five feeding frequencies (one meal in 2 d, one meal a day, two meals a day, four meals a day, and six meals a day) with three replicates was used. Survival of ayu post‐larvae was significantly (P 0.05) affected by feeding frequency but not by feeding rate. Survival of ayu improved linearly with feeding frequency at both feeding rates. Weight and length gains and specific growth rate (SGR) of ayu was significantly (P 0.05) affected by feeding frequency but not by feeding rate, with weight and length gains and SGR linearly elevated with increasing feeding frequency at both feeding rates. The greatest weight and length gains were observed in fish receiving six meals daily at both feeding rates; however, no significant difference in weight gain was observed among two, four, and six meals a day, or in length gain between four and six meals a day. Feed efficiency ratio (FER) was significantly (P 0.05) affected by both feeding rate and feeding frequency. FER linearly decreased with feeding frequency at both feeding rates or feeding rate in the same feeding frequency. When the total daily amount of feed supply was constant with various feeding frequencies at different feeding rates (one meal a day at 3% feeding rate and one meal in 2 d at 6% feeding rate, two meals a day at 3% feeding rate and one meal a day at 6% feeding rate, or four meals a day at 3% feeding rate and two meals a day at 6% feeding rate), improvement in survival, weight and length gains, and SGR was observed in fish with higher feeding frequency at lower feeding rate. Moisture, protein, and lipid content of fish were not significantly (P > 0.05) affected by either feeding rate or feeding frequency. However, lipid content of ayu linearly increased with feeding frequency at 6% feeding rate. The highest body lipid content was observed in fish receiving six meals daily at both feeding rates. Ash content of fish was significantly (P 0.05) affected by feeding frequency but not by feeding rate. Based on performance of ayu, it can be concluded that optimum feeding rate and feeding frequency for ayu post‐larvae (an initial weight of 0.15 g) were 3% per meal and four meals a day, respectively, under these experimental conditions.     

Effects of feeding frequency on food intake,growth and body composition of rainbow trout (Salmo gairdneri)

The effects of feeding frequency on food intake, weight change and relative proportions of the major body components were investigated at 10°C in a strain of hatchery-reared rainbow trout. Feeding frequencies were from one meal every second day to six meals per day, within the range common to current piscicultural techniques. Fish were fed a dry, pelleted diet either to satiation at each meal, or in restricted total daily amounts based on a percentage of their wet body weight. All fish were forced to swim at a constant speed of approximately one body length per second to minimize variability in growth and body composition.Maximum daily food intake occurred with just two feedings to satiation per day. Growth closely paralleled food intake. Neither specific growth rate nor whole body levels of moisture, lipid or protein were affected significantly by differences in feeding frequency. A trend towards increased body fat with more frequent feeding was observed among fish fed to satiation at each meal; this was believed to be the result of a somewhat higher total food intake than among less frequently fed fish. Fish fed a restricted daily ration divided into a number of meals exhibited smaller differences in lipid content.The general lack of response to feeding frequency was attributed primarily to the low metabolic rate of trout and to the characteristically slow rate of food passage in the digestive tract.     

Effects of feeding frequency and feed type on the growth,feed utilization and body composition of juvenile olive flounder,Paralichthys olivaceus

A factorial (3 × 4) feeding trial was conducted to investigate the effects of feeding frequency and feed type on the growth performance, feed utilization and body proximate composition of juvenile olive flounder. Three feed types including a sinking moist pellet (MP), a sinking dry pellet (DP) and a floating extruded pellet (EP) were used. Fish (average weight, 11.1 ± 0.4 g) were randomly distributed in thirty‐six 300 L tanks in a flowthrough system. Triplicate groups (30 fish per tank) of fish were fed each feed type to visual satiation at three meals per day, two meals per day, one meal per day and one meal every 2 days for 7 weeks. At the end of the feeding trial, the survival of fish was not significantly different among the treatments. Weight gain was affected by the feeding frequency. The highest weight gain was observed in fish fed the EP at three meals per day. The daily feed intake of fish fed the MP and DP tended to be higher than that of fish fed the EP at each feeding frequency. The feed efficiency and the protein efficiency ratio of fish fed the EP were higher than those of fish fed the MP and DP. The body proximate composition of fish was altered by the feeding frequency. The crude lipid content increased with the increase in the feeding frequency. The present findings suggest that three feedings per day at visual satiation of the floating EP may be sufficient for the maximal growth performance of olive flounder grown from 11 to 60 g.     

Effect of number of meals and frequency of feeding on voluntary feed intake of Colossoma macropomum (Cuvier)

Juvenile, 0.87 g Colossoma macropomum (Cuvier) were submitted to different ad libitum feeding regimes. Feeding frequency ranged from one to five meals per day and intervals between meals from 3 h to 24 h. Higher feeding frequencies resulted in higher feed uptake, a higher growth rate and a decreased feed utilization efficiency. Feed consumption was lower at 0700 h than at 1900 h. The amount of feed from different meals persisting in the digestive tract was determined with chromic-oxide-marked feed. This method revealed that with ad libitum feeding, about 21% of the feed remained uneaten. Feed losses did not differ significantly between feeding regimes. Feed accumulated in the digestive tract in the morning and early afternoon. In the late afternoon most feed rests disappeared from the digestive tract and feed consumption increased. It is suggested that feed uptake and growth of C. macropomum can be improved by extending the feeding period after 1900 h.     

Devising optimum feeding regimes and temperatures for the warmwater culture of eel, Anguilla anguilla L.

Abstract. This paper describes feeding experiments conducted with small eels under holding conditions and temperatures designed to mimic those on the farm. It was shown that frequent feeding allows highest consumption at 16°C and below because gut passage is slowed at these temperatures. At higher temperatures food consumption and conversion can be increased by feeding meals at a defined optimum frequency which was shown to rise with temperature. This optimum is associated with lowered activity levels which spare energy for growth. The underlying factor is a preference for meals at a size and feeding interval corresponding with the capacity and emptying of the stomach. A series of models have been formulated to allow prediction of optimum feeding regimes and understanding of consumption-conversion-growth-temperature interrelationships. Optimum conditions for growth are shown to occur at 26.5°C with maximum consumptions and a feeding frequency of either three or four times per day. This optimum temperature is shown to be lowered with reduced consumptions.     

Devising optimum feeding regimes and temperatures for the warmwater culture of eel,Anguilla anguilla L.*

Abstract. This paper describes feeding experiments conducted with small eels under holding conditions and temperatures designed to mimic those on the farm. It was shown that at temperatures up to 16°C highest daily consumptions occur with frequent feeding. This is because gut passage is slowed and limits consumption at these temperatures. At higher temperatures feed consumption and conversion can be increased by feeding meals at a defined optimum frequency which was shown to rise with temperature. This optimum frequency of feeding is associated with lowered activity levels which spare energy for growth. The underlying factor is a preference for meals at a size and feeding interval corresponding with the capacity and emptying of the stomach. Optimum conditions for growth are shown to occur at 26.5°C with maximum consumptions at a feeding frequency of either three or four times per 24-h day. This optimum temperature is shown to be lowered as daily feed intake is reduced.