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1.
Using rainbow trout, Oncorhynchus mykiss (Walbaum), of approximately 50 g, a 63 day feeding trial was undertaken to evaluate the efficacy of individual and multiple amino acid supplements in diets where soyabean meal was used as the principle protein source. Iso-nitrogenous diets (45% crude protein) were formulated where the control diet (F) contained fishmeal as the reference protein and a solvent extracted soyabean meal (S) replaced approximately 66% of this protein source. The soyabean containing diets were then supplemented with crystalline amino acids thus; methionine only, dual supplemented with two methionine and lysine levels and finally, a supplement comprising methionine, lysine, tryptophan, threonine, arginine and histidine. The results showed that soyabean meal (SBM) was inferior to the reference protein when SBM was used to replace 66% of the fishmeal and that no significant restoration in growth, feed efficiency and apparent net protein utilization was obtained by either methionine only or dual methionine and lysine supplementation. However, by comparison with the fish fed the unsupplemented, single and dual supplemented diets, multiple amino acid incorporation was associated with significantly improved percentage weight gain, specific growth rate and marginal improvements in apparent net protein utilization. However, performance was not equal to that of the fish fed the fishmeal based control diet. The results are discussed with respect to the level of each of the essential amino acids (EAA) as a proportion of the total EAAs (A/E index) of test diets by reference to the whole body tissue amino acid profile of rainbow trout.  相似文献   

2.
An 8-week feeding trial was conducted with cobia to determine the amount of soybean meal that could replace fish meal in formulated diets without reducing growth. Juvenile cobia (initial mean weight, 32 g) were fed 48% crude protein diets in which dietary protein was supplied by brown fish meal or a mixture of hexane extracted soybean meal and the fish meal, resulting in 10%, 20%, 30%, 40%, 50% and 60% of fish meal protein being replaced by soybean protein. The fish readily accepted all seven experimental diets and no fish died during the trial. Detrimental effects on growth performance were obvious when half of the fish meal protein was replaced by soybean protein. There existed a significant difference in fish weight gain, feed conversion ratio (FCR), protein efficiency ratio (PER) and net protein utilization (NPU) when the replacement level for fish meal protein was increased from 40% to 50%, indicating that up to 40% of fish meal protein can be replaced by soybean meal protein without causing reduction in growth and protein utilization. On the other hand, quadratic regression analysis shows a growth optimum at 16.9% replacement of fish meal protein by soybean meal protein. Lipid concentrations in the cobia muscle increased significantly as dietary soybean meal increased. Muscle concentrations of free threonine and histidine decreased as use of the soybean meal increased in the diets. Since methionine concentration in the test diets decreased from 2.52 to 1.36 g 16 g−1 N as the soybean meal protein replacement level was increased from 0% to 60% while all other essential amino acids remained relatively constant, dietary requirement of methionine was calculated assuming it was equally available between the two proteins. The broken-line model analysis based on fish weight gain shows a breakpoint when dietary methionine+cystine concentration was 2.66 g 16 g−1 N or 1.28 g 100 g−1 diet.  相似文献   

3.
An 8‐week feeding trial was conducted to evaluate the effects of replacing fish meal (FM) with soybean meal (SBM) and peanut meal (PM) on growth, feed utilization, body composition and haemolymph indexes of juvenile white shrimp Litopenaeus vannamei, Boone. Five diets were formulated: a control diet (FM30) containing 30% fish meal and four other diets (FM20, FM15, FM10 and FM5) in which protein from fish meal was substituted by protein from SBM and PM. The dietary amino acids of diets FM20, FM15, FM10 and FM5 were equal to those of the diet FM30 by adding crystalline amino acids (lysine and methionine). Each diet was randomly assigned to triplicate groups of 30 shrimps (initial weight = 0.48 g), each three times daily. The results indicated that shrimp fed the diets FM15, FM10 and FM5 had poor growth performance and feed utilization compared with shrimp fed the control diet. No difference was observed in feed intake, survival and body composition among dietary treatments. The plasma total cholesterol level of shrimp and the digestibility of dry matter, protein and energy contained in the diets decreased significantly with increasing PM and SBM inclusion levels. Results of this study suggested that fish meal can be reduced from 300 to 200 g kg?1 when replaced by a mixture of SBM and PM.  相似文献   

4.
The objective of the present study was to evaluate the effect of fish meal quality on growth, feed conversion and protein utilization in common wolffish. Anarhichas lupus L. The study involved comparison between low-temperature-processed (Norse-LT) and regular fish meal (NorSeaMink) included in dry pellets. Results obtained for these dry feeds were compared with those obtained using moist feed containing squid mantle. The results show better growth rate, feed conversion factor, protein efficiency rate, (PER) and productive protein values (PPVs), when using low-temperature-processed meals compared with regular fish meals in feed to wolffish. No specific differences were found in growth rate and feed conversion factor between fish fed diets containing low-temperature-processed meal or squid mantle. Whole body lipid content was highly influenced by dietary content. No effect of dietary moisture content was demonstrated in this study.  相似文献   

5.
A 65-day study was undertaken to evaluate the utilization of lysine-supplemented wheat gluten meal as a protein source for rainbow trout, Oncorhynchus mykiss (Walbaum). The performance of the trout fed wheat gluten was compared to that of trout where protein was principally supplied using fish meal and full-fat soyabean meal. Six isonitrogenous diets (approximately 45% crude protein) were formulated. Thus, the reference diet (FS) was based on fish meal and full-fat soya bean meal while a further five diets were formulated with a mixture of wheat gluten and wheat middlings used to isonitrogenously replace approximately 75% and 57% of the full-fat soya and fish meal respectively. Crystalline l -lysine representing 0.00%, 0.29%, 0.58%, 0.87% and 1.16% of the complete diet was then added to the wheat-gluten-based diets. Optimal performance in terms of weight gain and apparent net protein utilization was achieved by the fish fed a wheat-gluten-based diet supplemented with lysine (0.58%) yielding a digestible lysine level of 1.9% of the complete feed. Within the range of supplements provided, lysine digestibility was high. However, at the highest levels of supplemental lysine the relationship between uptake and supplement level was not linear. Additionally, arginine digestibility was not affected by the level of lysine supplementation. However, amongst the wheat-gluten-based diets, optimal performance was associated with a lysine: arginine ratio of 1.1: 1. Despite a lysine: arginine ratio of approximately 1.1: 1, the overall performance of the fish fed the fish-meal-soya-based reference diet was poorer than expected. The results are discussed with respect to optimal patterns of gross and digestible amino acids, lysine-arginine antagonism and the possible relationship between antinutritional factors and the poor performance of the fish fed the fish-meal-soya-based reference diet.  相似文献   

6.
The relative contribution of the dietary nitrogen supplied by fish meal and a biofloc meal to the growth of Pacific white shrimp was evaluated using stable isotope analysis. Biofloculated material was obtained from an experimental tilapia culture system. Five formulated diets were supplied. Two of them consisted in isotopic controls having only fish meal or biofloc meal as protein source. Three mixed diets were formulated with varying proportions of these ingredients on a dietary nitrogen basis (75:25, 50:50 and 25:75). At the end of the trial, survival rates were similar (92–100%) but significant differences in mean final weight were observed and a negative correlation between the inclusion of biofloc meal and weight gain was evidenced. Mean final weight in shrimp fed on diet containing only fish meal was 2.8 g, while mean final weight of animals fed on diet containing 50% biofloc was 1.9 g. Isotopic mixing models indicated that all diets contributed higher proportions of dietary nitrogen from fish meal than from biofloc meal. Dietary nitrogen available in diets containing 25%, 50% and 75% of biofloc meal was incorporated in muscle tissue as 5%, 41% and 64% respectively. Diet supplying 25% of nitrogen from biofloc was the only mixed diet eliciting growth comparable to diet containing only fish meal. Lower growth and nitrogen deposition in shrimp fed on diets containing high proportions of biofloc meal were possibly associated to the use of only two protein sources and a restriction of essential amino acids.  相似文献   

7.
An 8‐week feeding trial was conducted to evaluate the effects of replacing fish meal with soybean meal (SBM) on growth, feed utilization, and nitrogen (N) and phosphorus (P) excretion of juvenile Pseudobagrus ussuriensis (initial average weight 0.50 ± 0.00 g). Seven isonitrogenous and isolipidic diets were formulated to contain SBM to replace fish meal protein at 0% (S0), 10% (S10), 20% (S20), 30% (S30), 40% (S40), 50% (S50) and 60% (S60) respectively. To investigate the effects of supplementation with crystalline amino acid to balance diet S60, one diet was formulated to add 0.30% methionine (SM60). The results showed that there was no significant difference in weight gain among fish fed S0, S10, S20, S30 and S40 diets, however, a significant reduction in this variable occurred when 50% and 60% of fish meal protein was replaced by SBM (P < 0.05). Apparent digestibility coefficients of dry matter, crude protein and phosphorus of diets were affected by dietary SBM levels. N and P excretion indicate that fish meal replacement by SBM led to an increase in N excretion, but led to a reduction in P excretion. No differences were detected in growth, feed utilization and N and P excretion between fish feed diets S60 and SM60. The results of this study show that 40% of fish meal protein could be replaced by SBM in diets of juvenile P. ussuriensis without having a significant negative effect on growth or feed efficiency, but that higher dietary SBM levels reduce fish performance.  相似文献   

8.
To be able to study nutrient requirement and utilization in any species, a diet supporting normal feed intake and growth equally well as a traditional fish meal‐based diet is needed. Additionally the formulation of the diet should allow low levels of the nutrient under study. When studying the amino acid metabolism and requirements, one cannot rely on the fish meal‐based diets as fish meal are nicely balanced according to requirements. Therefore the current study aimed to develop a plant protein‐based diet (with low fish meal inclusion) to be used in the nutritional studies of Senegalese sole juveniles supporting feed intake and growth close to that obtained in a fish meal‐based control feed. Two experiments were conducted to evaluate whether Senegalese sole juveniles would accept and utilize diets containing high plant protein inclusion. For testing the acceptance of high plant protein inclusion, two diets were formulated: a reference diet that contained fish meal as the main protein source (450 g kg?1 dry matter) whereas in the test diet, fish meal was substituted by a mixture of plant ingredients (soybean meal, corn and wheat gluten) with l ‐lysine supplementation. In order to improve the palatability, 50 g kg?1 squid meal was added to both diets. The indispensable amino acids (IAA) profile of the test diet was made similar to the control diet by adding crystalline amino acids. Further, automatic feeders were used to improve the feed intake. Fish (24 g initial body weight) were fed the diets for a period of 4 weeks. As fish accepted both diets equally well, a second study was undertaken to test the growth performance. Fish (6 g initial BW) were fed the diets for a period of 12 weeks. The use of automatic feeders to deliver the feed and the addition of both squid and balancing the indispensable amino acids resulted in growth performance and accretion not differing from the fish meal fed control. It can be concluded that juvenile Senegalese sole are able to grow and utilize high plant‐protein diets when both diet composition and feeding regime are adequate for this species.  相似文献   

9.
为探究2种蛋白源单一和混合替代鱼粉对大口黑鲈生长性能、血清生化指标和肠道组织学的影响,实验用发酵豆粕(FSM)、肉骨粉(MBM)和发酵豆粕+肉骨粉(FSM+MBM)混合物(1∶1)等蛋白替代基础饲料(FM,含鱼粉350 g/kg)中150 g/kg的鱼粉,使鱼粉含量降为200 g/kg,共配制成4种等氮等脂的实验饲料,记为FM (对照组)、FSM、MBM和FSM+MBM组,投喂初始体质量为(21.2±0.1) g的大口黑鲈8周。结果显示,与对照组相比,各替代组的增重率均无显著差异,但FSM组的增重率显著低于FSM+MBM组。此外,FSM组的饲料系数较对照组和MBM组显著升高。各组在全鱼成分(水分、粗蛋白、粗脂肪、粗灰分)和干物质消化率、蛋白质消化率以及蛋白质沉积率上无显著差异,而FSM组的蛋白质效率和脂肪沉积率显著低于对照组。此外,FSM组的血清谷草转氨酶显著增加,而血清总抗氧化能力以及超氧化物歧化酶、溶菌酶活性显著降低。在前肠形态学方面,各替代组的绒毛宽度均显著低于对照组,FSM组的绒毛高度、肌层厚度以及绒毛周长显著高于对照组。以上结果表明,在鱼粉含量为350 g/kg的饲料中,MB...  相似文献   

10.
A feeding trial was conducted to investigate the effects of the replacement of dietary fish meal and fish oil with oilseed meals (soybean or canola) and canola oil on growth, nutrient utilization, body composition, diet digestibility and hematological parameters of rainbow trout Oncorhynchus mykiss. Seven diets were used; the control diet (designated FM) contained fish meal and fish oil as the main protein and lipid sources. For the experimental diets, 40% of fish meal protein was substituted with soybean meal, canola meal or a soybean/canola meal mixture, and these diets (designated SM, CM and SCM, respectively) contained fish oil as the lipid source. Three additional diets (SM?+?CO, CM?+?CO and SCM?+?CO) were formulated with the same vegetable protein meals but with fish oil replaced by canola oil. Fish were fed twice daily to apparent satiation for 11?weeks. The growth of fish fed the CM?+?CO diet was significantly lower than that of fish fed the FM, SCM, SM?+?CO and SCM?+?CO diets. The feed conversion ratio (FCR) was significantly better in fish fed the FM and SCM?+?CO diets than in fish fed the CM and CM?+?CO diets. Furthermore, feed intake was significantly lower for fish fed the CM?+?CO diet than in fish fed the SCM diet, and lipid digestibility of the CM?+?CO diet was significantly lower than that of all other diets. No significant differences of body composition were observed. Circulating leukocyte levels, leukocyte ratios and serum lysozyme activity remained unaffected by dietary treatment. However, it was observed that fish fed the CM?+?CO diet displayed hematocrit levels significantly lower (P?<?0.05) than that of fish fed the other diets. The results indicate that when diets contain either fish oil or canola oil, canola meal and soybean meal can be incorporated into rainbow trout feeds at a combined 32% inclusion level (replacing 40% of fish meal protein) without inducing significant negative effects on growth, nutrient utilization or health.  相似文献   

11.
Animal by-product meals (ABM) were substituted for fish meal in five experimental diets for Nile tilapia fry, Oreochromis niloticus (L), with 25%, 50%, 75% and 100% substitution. Two diets with 100% ABM were tested, one with 50:50 animal lipid:soybean oil, and the other with 100% fish oil as attractant. In general, the best growth and feeding performance was obtained with a control diet based on fish meal as the sole protein, but the results were not statistically different from those obtained with 75% and 100% ABM with soybean oil. A simple cost analysis suggested better economic efficiency when tilapia were fed with 100% ABM. It was concluded that animal by-product meal can be used as a sole protein source in commercial diets for Nile tilapia fry, without affecting growth and food utilization of the fish, improving the economics of feeding in comparison with fish meal.  相似文献   

12.
An indoor feeding trial in a flow-through marine water system was performed to evaluate the feasibility of using dehulled lupin Lupinus albus seed meal as a protein source to replace fish meal in diets for the juvenile Penaeus monodon. Five isonitrogenous (40% crude protein) diets formulated by replacing 0, 25, 50, 75, and 100% of fish meal protein by lupin meal protein were fed to shrimp (mean initial weight of 4.32 ± 0.23 g) three times daily at a feeding allowance of 5% body weight per day for 42 days. Shrimp fed diets with 0, 25, 50 and 75% replacement had similar (P > 0.05) weight gain, dry matter feed intake, feed conversion ratio (FCR), protein efficiency ratio (PER), and apparent net protein utilization (ANPU). Shrimp fed the highest dietary inclusion level of lupin meal (100% replacement) had significantly (P < 0.05) lower responses for all the above parameters than shrimp fed all other diets. Survival was high (87–100%) and similar for all diets. Apparent dry matter digestibility (ADMD) of diets with 25, 50, 75 and 100% replacement of fish meal with lupin meal was similar (75.6–76.6%) and significantly (P < 0.05) higher than that of diet with 0% replacement (73.9%). Diets containing the two highest lupin inclusion levels (75 and 100% replacement) had significantly (P < 0.05) better apparent protein digestibility (APD) than those containing the two lowest lupin meal inclusion levels (0 and 25% replacement). There were no significant differences (P > 0.05) in whole-body composition (dry matter, protein, lipid and ash) of shrimp fed on the various diets. Pellet water stability was inversely related to level of lupin meal inclusion. It was found, in this study, that up to 75% protein of fish meal can be replaced with the protein of dehulled lupin seed meal in diets for juvenile P. monodon. The diet with total replacement of fish meal containing 40% lupin meal was utilized very poorly by the shrimp.  相似文献   

13.
Six isonitrogenous (350 g kg−1 crude protein) and isoenergetic (17573 kJ kg−1) experimental diets incorporating raw and fermented sesame ( Seasamum indicum ) seed meal at 200, 300, and 400 g kg−1 into a fishmeal based diet were fed to rohu Labeo rohita fingerlings for 60 days and the growth performance and feed utilization efficiency of the fish was studied. The antinutritional factor phytic acid, from raw sesame seed meal, could be reduced below detection limit by fermentation with lactic acid bacteria ( Lactobacillus acidophilus ). Fermentation of the oilseed meal resulted in reduction of the tannin content from 20 to 10 g kg−1. In terms of growth response, feed conversion ratio and protein efficiency ratio, a diet containing 400 g kg−1 fermented sesame seed meal resulted in a significantly ( P  < 0.01) best fish performance. In general, growth and feed utilization efficiencies of fish fed fermented sesame seed meal diets were superior to those fed raw oilseed meal diets. Apparent protein digestibility (APD) values decreased with increasing levels of raw oilseed meal. APD was, however, significantly ( P  < 0.01) higher at all levels of incorporation of fermented sesame seed meal, while diets containing raw oilseed meal resulted in poor protein and lipid digestibility. Carcass protein and lipid contents of fish fed fermented sesame seed meal diets increased with increasing level of incorporation, being highest with 400 g kg−1 fermented oilseed meal-containing diet. The results showed that sesame seed meal may be incorporated in carp diets up to 200 g kg−1 and 400 g kg−1 in raw and treated (fermented) forms respectively.  相似文献   

14.
An 8‐week feeding trial was conducted to evaluate the effects of replacing soybean meal (SBM) with canola meal (CM) on growth, feed utilization, body composition and haematological indices of juvenile hybrid tilapia (Oreochromis niloticus×Oreochromis aureus). Six isonitrogenous diets containing graded levels of CM (0, 95, 190, 285, 380 and 634 g kg?1 of diet corresponding to 0%, 15%, 30%, 45%, 60% and 100%, respectively, of protein from SBM) to replace SBM on an equal protein basis were fed to triplicate groups of juvenile fish (initial weight=6.3 g). The results indicated that up to 30% of SBM could be replaced by CM without causing a significant reduction in growth performance. Fish fed with diets in which CM replaced over 45% of SBM had a significantly lower protein efficiency ratio and a significantly higher feed conversion ratio than fish fed with other diets. The apparent digestibility coefficients (ADC) of dry matter, protein and phosphorus were lowest for fish fed the CM100 diet. Significant differences in haemoglobin, haematocrit and white blood cell concentration were found in fish fed diets with different CM levels. It is concluded that up to 19.02% CM can be used to replace 30% of SBM in diets for juvenile hybrid tilapia without compromising growth, feed conversion and protein utilization.  相似文献   

15.
Five experimental diets (PPC1, PPC2, PPC3, PPC4 and PPC5) containing about 465 g kg−1 crude protein were formulated to contain graded levels of potato protein concentrate (PPC) (a by-product of potato starch manufacturing) by replacement of fish meal protein. The contents of PPC were 0, 94, 200, 304 and 510 g kg−1 respectively. The diets were prepared isonitrogenously and isocalorically. A 6-week growth trial was conducted with rainbow trout, Oncorhynchus mykiss (Walbaum), at about 14°C to evaluate the potential use of the potato protein concentrate in trout diets.
The results showed that fish fed diets containing PPC showed decreased growth, feed utilization and condition factor, and increased mortality when PPC constituted the sole protein source. Incorporation of PPC in the diets resulted in decreased dry matter, protein and fat and increased ash contents of the fish body. In conclusion, the type of potato protein concentrate used, especially at high levels, was not suitable as an ingredient in trout feed.  相似文献   

16.
The aim of this trial was to compare the performance of rainbow trout fed diets including local or imported fish meal as the main protein sources, and to test the effect of reducing the fish meal content or including a fish protein hydrolysate in the diets. Two experimental diets were formulated to include 35% (diet 2) or 20% (diet 3) of a local processed whole fish meal; two other diets were formulated similar to diets 2 and 3 but with 5% fish protein hydrolysate replacing the same amount of fish meal (diets 4 and 5 respectively); a diet similar to diet 2, but including Norwegian fish meal, was used as a control (diet 1). The growth trial lasted 14 weeks and was carried out in floating net cages (325‐L capacity), with duplicate groups of 20 rainbow trout of an initial average weight of 58 g. The apparent digestibility coefficients (ADC) of the diets were evaluated in a separate laboratory trial. At the end of the growth trial, there were no significant differences in growth rate and protein efficiency ratio among groups. Feed conversion ratios were significantly better in groups fed diets 3, 4 and 5 than in the other groups. Nitrogen retention (% of N intake) was significantly higher in fish fed diets 4 and 5 than in those fed diet 2. There were no significant differences in energy retention (% of energy intake) among groups. At the end of the trial, there were no significant differences among groups in proximate composition of whole fish. The ADC of protein, energy and phosphorus of diets 1 and 2 were significantly lower than those of diets 3 and 5. It was concluded that, under the experimental conditions tested, performance of rainbow trout fed practical diets including good quality local processed fish meal is similar to that of fish fed diets including Norwegian fish meal. A reduction in the fish meal from 35% to 20% of the diet or the inclusion of a fish protein hydrolysate had no negative effects on growth performance and improved feed utilization.  相似文献   

17.
A study was conducted to investigate red crab Pleuroncodes planipes (Stimpson) as a protein source in experimental diets for postlarvae and juvenile brown shrimp Farfantepenaeus californiensis (Holmes). Four experimental diets were prepared. The base diet contained 10% shrimp meal, 25% fish meal and 27% soy meal plus other ingredients. Complete substitution of shrimp meal with red crab meal (RCM) was done on the remaining diets. Additionally, 5% of the soy meal was replaced with RCM in one diet, and 4% of the fish meal was replaced with RCM in the last diet. A commercial diet (36% crude protein) was used as an external comparison diet to provide a basis to evaluate the growth of shrimp on the test diets. The trial with shrimp postlarvae showed that diets containing RCM produced better results in terms of final weight (3.24–3.55 g), growth rate (0.044–0.046 g d?1) and feed conversion ratio (FCR) (3.7–3.8) than the base or the commercial comparison diets. The FCR was significantly different between the base diet (4.5) and the commercial diet (5.5). Final weight (3.83 g) and growth rate (0.044 g d?1) were higher when the diet replacing 4% fish meal was used to feed juveniles. The commercial diet produced the lowest values of final weight (2.57 g) and growth rate (0.025 g d?1) and the highest FCR (5.6) (P<0.05). These results indicate that the use of P. planipes as a replacement for traditional ingredients in shrimp rations is desirable.  相似文献   

18.
A feeding trial was conducted to evaluate the effect of replacing fish meal protein with fermented soybean meal (FSM) on the growth performance, feed utilization, amino acid profile, body composition, morphological parameters, activity of antioxidant and digestive enzymes of black sea bream (Acanthopagrus schlegeli) juvenile. Five isonitrogenic and isolipidic diets were prepared with levels of 0 (control), 80, 160, 240 and 320 g kg?1 FSM. Triplicate groups (40 fish per tank) of juvenile black sea bream with initial weight of 1.17 ± 0.04 g were hand‐fed to visual satiation at three meals per day for 8 weeks. The fish fed diets containing different levels of FSM had no significant differences regarding survival and specific growth rate compared with control group. Feed and protein efficiency ratios of fish fed diet containing 320 g kg?1 FSM were significantly lower than those of control group. Daily feed intake and daily protein intake of fish fed diet containing 240–320 g kg?1 were significantly higher than those of control group. Hepatosomatic index and condition factor of fish were not affected by different dietary FSM level. Fish fed diets containing 240–320 g kg?1 FSM had significantly higher visceral somatic index than control group. Whole body proximate and amino acid compositions of fish were not affected by dietary FSM level. The activity of digestive enzymes in the intestine was not affected by dietary FSM level. The activity of glutathione peroxidase in liver was significantly higher for fish fed the diet containing 160 g kg?1 FSM compared with control group. This study showed that up to 40% fish meal in the diets of juvenile black sea bream could be replaced by fermented soybean meal with supplementation of methionine, lysine and taurine.  相似文献   

19.
Abstract. Dried earthworm meal derived from the species Eisenia foetida was nutritionally evaluated as a replacement for herring meal in production diets from rainbow trout, Salmo gairdneri Richardson. Increasing levels of dried E. foetida meal, from 5 to 30% by weight, were included in the diet and the response of fish fed these diets was compared to fish fed a control diet without earthworm meal inclusion. There was no evidence of any adverse effect on the growth performance or feed utilization efficiency of fish fed diets containing these low levels of dried E. foetida meal. There was. however, a significant increase in the whole carcass lipid content of fish fed diets containing 5. 10 and 20% dried E. foetida meal. Concent rations of iron, zinc, lead, copper and cadmium within the whole fish carcass were not significantly elevated as a result of including these low levels of the dried E. foetida meal in diets for rainbow trout.  相似文献   

20.
A 12‐week experiment was conducted to evaluate the suitability of gambusia (Gambusia affinis) fish meal (GFM) as a partial and complete substitute for the protein supplied by herring fish meal (HFM) in diets for red tilapia fingerlings (mean weight 0.42 g). Seven isonitrogenous (35% crude protein), isolipidic (9% fat) and isoenergetic (15.9 kJ DE‐g?1 diets were formulated in which GFM replaced 0.0, 10, 25, 50, 75, 90 and 100% of the protein supplied by HFM. In general, GFM exhibited good potential as a substitute for HFM in red tilapia diets with no adverse effects on growth, feed efficiency, body composition, blood parameters or apparent digestibility of dry matter, protein and gross energy compared with the HFM‐based control diet. Growth performance (in terms of final weight, weight gain, per cent increase in weight and growth rate) of fish fed diets containing GFM at 25 or 50% level of replacement for HFM‐protein (diets 3 and 4) was statistically higher than for fish fed diets containing GFM at replacement levels >50%. Diet 4 had the best economic efficiency of fish weight gain. Partial or complete substitution of GFM for HFM did not affect feed utilization efficiency (in terms of FCR, FER, PER and APU) or digestibility coefficients of dry matter, protein and gross energy compared with those of the HFM‐based diet. Apparent protein digestibility varied little between diets, ranging from 84.2 to 87.3% with no significant differences. Survival of fish fed all the experimental diets (except for fish fed GFM at 90 or 100% level of replacement for HFM‐protein) was comparable with that of fish fed the control diet and ranged from 91.7 to 98.3%.  相似文献   

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