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1.
This study was designed to evaluate the efficacy of eight sources (designated A–H) of soybean meal (SBM) which included six new non‐genetically modified soya varieties in practical feed formulation for Pacific white shrimp, Litopenaeus vannamei, using both growth and digestibility trials. A soybean meal‐based reference diet was formulated using conventional soybean meal (527 g kg?1 diet), which was then replaced on an isonitrogenous basis with various other experimental soybean meals. In a 6‐week growth trial, shrimp in four replicate tanks per dietary treatment (10 shrimp per tank, initial weight 0.52 ± 0.04 g) were cultured in a recirculating system. There were no significant differences with respects to per cent weight gain and survival across all dietary treatments; however, final weights and feed conversion ratio (FCR) were lower in shrimp offered diet 3. Apparent digestibility coefficients for the eight (A–H) different soybean meals were determined in L. vannamei for dry matter (ADMD), gross energy (ADE) and crude protein (ADP) using 10 g kg?1 chromic oxide as inert marker with 70 : 30 replacement techniques. Coefficients ranged from 71.3% to 88.3%, from 76.6% to 91.3% and from 93.6% to 99.8%, for ADMD, ADE and ADP, respectively. Improved digestibility values were observed in soybean C which was characterized by crude protein (471 g kg?1), crude fat (97 g kg?1), low cooking temperature (180 °C), higher nitrogen solubility index (689 g kg?1) and protein dispersibility index (619 g kg?1). This indicates that new lines of soybean meal can be used to improve digestibility coefficients in shrimp feeds.  相似文献   

2.
Growth and digestibility trials were conducted to evaluate the use of flash dried yeast (FDY) as a supplement in practical shrimp feeds. The six‐week growth trial evaluated the effects of FDY supplementation (0, 10, 20, 40 and 60 g kg–1) in the plant‐based practical diet on the performances and proximate compositions of juvenile Pacific white shrimp, Litopenaeus vannamei. Final biomass, final mean weight, per cent weight gain (WG), feed conversion (FCR) and protein retention efficiency (PRE) of Pacific white shrimp were not significantly influenced when FDY was added up to 40 g kg–1 of the diet. However, 60 g kg–1 FDY supplementation significantly reduced growth, feed utilization and protein retention. Supplementation of FDY in the practical diets of Pacific white shrimp did not affect protein, moisture, lipid, crude fibre, and ash content of whole shrimp body. Apparent digestibility coefficients of energy, protein, and amino acid (AA) for FDY were determined using chromic oxide as an inert marker and the 70:30 replacement technique. The energy and protein digestibility of FDY were 38.20% and 53.47%, respectively, which were significantly lower than fishmeal (FM) and soybean meal (SBM) that were run at the same time. Most amino acid digestibility of FDY was lowest among the three ingredients tested. Results of this work indicated that energy, protein and amino acid digestibility of FDY are lower compared to SBM and FM, and high levels supplementation (≥60 g kg–1) of FDY can cause negative effects to the growth response of Pacific white shrimp. Based on these results, further research regarding the effects of the low level inclusion of FDY in practical diets on immune responses of Pacific white shrimp is warranted.  相似文献   

3.
Apparent digestibility coefficients of dry matter, crude protein, lipid and energy, and amino acids availability in white fish meal, brown fish meal, meat meal, fermented soybean meal, soybean meal and rapeseed meal were determined for loach (Misgurnus anguillicaudatus) (12.05 ± 0.21 g), using a reference diet with 5 g kg?1 chromic oxide and test diets that contained 700 g kg?1 reference diet, by weight, and 300 g kg?1 of the test feed ingredients. The juvenile loach was held in 300‐l tanks at a density of 30 fish per tank. White fish meal, brown fish meal, meat meal and fermented soybean meal had highest apparent digestibility coefficients (ADCs) of dry matter, crude protein and gross energy among ingredients tested, ranged from 50.4% to 60.9% for dry matter, from 64.6% to 88.4% for crude protein and from 57.9% to 79.0% for gross energy. The apparent digestibility coefficients of dry matter ranged from 61.0% to 66.9% for animal products and 50.4% to 60.7% for plant products. For crude protein, apparent digestibility coefficients of protein exceeding 80% were observed for white fish meal, brown fish meal, meat meal and fermented soybean meal, and the apparent digestibility coefficients of protein in rapeseed meal were the lowest among all the treatments. Lipids from both animal and plant feedstuffs were poorly digested by loach, ranging from 64.0% to 77.6%. The apparent digestibility coefficients of energy were similar to those of dry matter and protein, and the highest and lowest ADCs of energy were found in WFM and RM, respectively. The loach used dietary phosphorus from the animal feedstuffs more efficiently than from plant feedstuffs (soybean meal and rapeseed meal), with ADC‐values ranging from 42.3% to 53.1% and from 25.1% to 32.7%, respectively. For the animal products, the availabilities of amino acids in white fish meal and brown fish meal were higher than that in meat meal, expect for Met, Asp, Pro, Gly, and Cys. Among all the plant products, the availabilities of amino acids in fermented soybean meal were higher than in soybean meal and rapeseed meal, and thus had a greater potential to be used as a dietary replacement of fish meal in loach diets.  相似文献   

4.
Apparent digestibility coefficients (ADCs) of dry matter, crude protein, crude lipid, gross energy, phosphorus and amino acids in Peruvian fish meal, poultry by‐product meal, meat and bone meal, spray‐dried blood meal, hydrolysed feather meal, corn gluten meal, soybean meal, peanut meal, cottonseed meal and rapeseed meal were determined for juvenile snakehead (Ophiocephalus argus) with initial mean body weight of 78.1 g. A reference diet and test diets that consisted of a 70 : 30 mixture of the reference diet to test ingredient were used with 5 g kg?1 Cr2O3 as an external indicator. Fish meal, poultry by‐product meal and corn gluten meal had higher ADCs of dry matter, crude protein, and gross energy among ingredients tested. Dry matter ADCs ranged 61.9–81.5% for animal ingredients and corn gluten meal and ranged 52.2–68.0% for soybean meal, peanut meal, cottonseed meal and rapeseed meal. Energy ADCs of ingredients followed similar trends to differences in dry matter digestibility. Protein ADCs of animal and plant ingredients ranged 73.6–92.8% and 75.3–85.6%, respectively. Amino acid ADCs generally reflected protein digestibility. Lipid ADCs were relatively high for the ingredients tested. Phosphorus ADCs of animal and plant ingredients ranged 39.5–65.2% and 38.7–57.1%, respectively.  相似文献   

5.
Due to the variations in nutrient quality of soybean meal (SBM) that is a result of differences in production location and processing specifications, a study was conducted to determine the fluctuations in apparent digestibility coefficients of differently sourced SBM fed to Pacific white shrimps (Litopenaeus vannamei). Twenty‐four SBM‐based diets were formulated by mixing a basal diet and test ingredients on a dry matter basis (70:30 ratio), while 1% chromic oxide was used as the inert marker. The digestibility trial was carried out in a semi‐closed recirculation system with six replicate groups per treatment (mean shrimp weight of 10.2 g). Significant differences were observed for apparent dry matter, energy and protein digestibility coefficients (p < .05 was considered significant) among 24 sources of SBM and digestibility values ranged from 45% to 90%, 56% to 93% and 87% to 98%, respectively. Based on multivariate analysis, acid detergent fibre, neutral detergent fibre, lignin, raffinose and trypsin inhibitor were screened as the key chemical characteristics in SBM that influenced digestibility of nutrients in Pacific white shrimps. Variations in growth performances of shrimp were in line with the variations in apparent digestibility coefficients of SBM verifying the importance of digestibility data in shrimp feed formulations.  相似文献   

6.
Accurate digestibility coefficients for protein, energy, and lipid are needed by feed formulators to optimize diets to meet nutritional requirements and to substitute ingredients cost‐effectively. Of particular interest is protein, which accounts for the majority of shrimp feed content and expense. The current study evaluated seven cottonseed meal and protein products. Most of the samples were derived from a glandless cotton variety that lacks significant levels of the antinutritive compound, gossypol. The various protein fractions were evaluated for apparent crude protein, crude lipid, and energy digestibility when fed to juvenile Pacific White Shrimp, Litopenaeus vannamei. Apparent energy digestibility for the protein fractions derived from the glandless seed ranged from 76.7% for ground kernels to 94.6% for protein isolate, and these values were greater than the value obtained for the commercial meal that contained gossypol (64%). Apparent protein digestibility for the six glandless‐cotton‐based samples varied from 72.3% for the ground full‐fat kernels to 94.1% for the protein isolate, and these values were mostly higher than the value obtained for the commercial meal (82.3%). The high apparent digestibility values demonstrate that low‐gossypol cottonseed protein products may be useful as a cost‐effective replacement for more expensive protein sources in L. vannamei diets.  相似文献   

7.
Apparent digestibility coefficients of dry matter (DM), crude protein, crude lipid, gross energy, phosphorus and amino acids in Peruvian fish meal (FM), fermented soybean meal, extruded soybean meal, soybean meal, peanut meal, wheat gluten meal, corn gluten meal, shrimp byproduct meal, meat and bone meal (MBM), poultry meat meal and plasma protein meal (PPM) were determined for white shrimp (Litopenaeus vannamei). A reference diet (RF) and test diets (consisting of 70% RF diet and 30% of the feedstuff) were used with 0.5% chromic oxide as an external indicator. A total of 1440 shrimp (initial mean body weight 1.05 ± 0.01 g) were randomly stocked into thirty‐six 500‐L fibreglass tanks with 40 shrimp per tank and three tanks per diet. Faeces were collected from triplicate groups of shrimp by a faecal collection vessel attached to the shrimp‐rearing tank. The shrimp were fed to apparent satiation four times a day and the feeding experiment lasted for 6 weeks. Statistics indicate that apparent DM digestibilities for white shrimp (L. vannamei) were the highest for FM, ranged 52.83–71.23% for other animal products and 69.98–77.10% for plant products. The protein and lipid from plant and animal sources were well digested by white shrimp. Apparent protein and lipid digestibility were in the range 87.89–93.18% and 91.57–95.28%, respectively, in plant products, and 75.00–92.34% and 83.72–92.79%, respectively, for animal products. The white shrimp demonstrated a high capacity to utilize phosphorus in the ingredients. The apparent phosphorus digestibility ranges of animal feedstuffs and plant feedstuffs were 58.90–71.61% and 75.77–82.30% respectively. Amino acid availability reflected protein digestibility, except that in MBM, for which the availability of some amino acid was lower, possibly due to protein damage during processing. Digestibility information could promote the use of ingredient substitution in least‐cost formulated diets for white shrimp.  相似文献   

8.
Apparent digestibility coefficients (ADCs) for dry matter, crude protein, energy and essential amino acids for five commonly used feed ingredients were determined for juvenile spotted rose snapper Lutjanus guttatus (average body weight 90.6 g). ADCs were determined using the stripping technique to collect faeces after fish were fed a reference diet and test diets composed of 700 g kg?1 reference diet and 300 g kg?1 test ingredient. Chromic oxide (Cr2O3) was used as an inert indicator. Ingredients tested included sardine fishmeal (FM), canola meal (CM), tuna by‐products meal (TBM), poultry by‐product meal pet grade (PBM‐PG) and solvent‐extracted soybean meal (SBM). In general, all ingredients showed high digestibility values for all essential amino acids, although differences were detected among ingredients. ADC values for dry matter, protein and energy ranged 77.0–80.4%, 84.3–82.5% and 89–88.8%, respectively, for marine ingredient and land‐based animal protein sources, and 75.0–74.2%, 81.5–80.9% and 87.4–86.8%, respectively, for the plant‐based protein source. SBM, TBM and PBM‐PG should be further evaluated in feeding trials as partial FM replacements in rose snapper L. guttatus diets. Knowledge of ADC values for these ingredients will allow feed producers to develop nutritionally balanced, low‐cost feed formulations for this species.  相似文献   

9.
A study was conducted to determine apparent digestibility coefficients for dry matter (ADMD), crude protein (ACPD) and gross energy (AED) of selected ingredients in diets for juvenile Penaeus setiferus . Ingredients tested were corn grain, cottonseed meal, crab meal, grain sorghum, meat and bone meal, menhaden fish meal, rice bran, rice grain, shrimp meal, soybean meal, squid liver powder, wheat flour, wheat gluten, wheat middlings and wheat shorts. ADMD coefficients of test ingredients ranged from 22% to 100% and appeared to be related to the fibre, ash and starch content of the ingredient. ACPD coefficients ranged from 58% to 100%. Plant protein supplements (soybean meal and cottonseed meal) were utilized as efficiently as, or better than, animal protein supplements (squid liver powder, menhaden fish meal, meat and bone meal, shrimp meal and crab meal). ACPD coefficients for meat and bone meal, shrimp meal and crab meal (58–59%) were significantly lower than those for menhaden fish meal (76%) and squid liver powder (82%). AED coefficients (44–100%) varied significantly among plant products of similar proximate composition. Corn grain and wheat flour were better utilized by P. setiferus than other high-starch energy supplements. Wheat gluten exhibited the highest ADMD, ACPD and AED coefficients of all ingredients tested.  相似文献   

10.
Soybean coproducts are important protein sources in aquaculture because of their amino acid profile. Tilapia can be reared on soybean coproducts as the only source of dietary protein without compromising growth. This study estimated apparent digestibility coefficients for five soybean coproducts for juvenile Nile tilapia, Oreochromis niloticus, fed with extruded diets. A reference diet and test diets consisting of 70% reference diet and 30% coproduct ingredient were formulated, along with 5.0 g kg?1 chromic oxide (Cr2O3) as a marker. Apparent digestibility coefficients (ADC) for dry matter (ADCDM), gross energy (ADCGE) and crude protein (ADCCP) for soybean coproducts were estimated as 84.2–88.4%, 86.9–91.1% and 96.8–97.9%, respectively. ADCDM and ADCCP values did not vary among the ingredients, but low‐protein soybean meal exhibited lower ADCGE values than did soybean protein concentrate. ADCs of all amino acids were >95%, and mean ADCs for amino acids were similar to the values observed for ADCCP. Soybean coproducts had good nutritional value in extruded diets fed to tilapia. Methionine, histidine and valine were the limiting amino acids in all evaluated ingredients.  相似文献   

11.
Apparent digestibility coefficients (ADCs) of dry matter, crude protein, lipid, energy, phosphorus and amino acids in white fish meal, soybean meal, rapeseed meal and peanut meal were determined for Synechogobius hasta (28.65 ± 0.43 g, mean ± SD), using a reference diet with chromic oxide indicator and test diets that contained 70% reference diet, by weight, and 30% of feed ingredients. The juvenile S. hasta were held in 300 L tanks at a density of 30 fish per tank respectively. Faeces were collected from three replicate groups of fish by siphoning. The ADCs of dry matter and energy were the highest in white fish meal and the lowest in rapeseed meal ( P <0.05). Crude protein ADC was the lowest in rapeseed meal ( P <0.05) and showed no significant differences among other treatments ( P >0.05). The highest phosphorus ADC was observed in white fish meal and differences were not marked for other treatments ( P >0.05). Lipid ADC were above 90% and showed no significant differences among the treatments ( P >0.05). Amino acid availability values for the test ingredients followed similar trend to values of protein digestibility. All amino acids were more available from fish meal than from plant protein ingredients. Among three plant meals, the availability of amino acids was higher in peanut meal and lower in rapeseed meal.  相似文献   

12.
Studies were conducted with Atlantic cod, Gadus morhua (L.), to determine the apparent digestibility coefficients (ADCs) of protein and energy and the digestible energy (DE) content in feed ingredients widely available in Canada. We also tested the assumption of “independency” used in digestibility studies. The feed ingredients included two fish meals (herring, anchovy), three crustacean by-product meals (whole krill, crab, shrimp), two animal by-product meals (poultry by-product, hydrolyzed feather), six oilseed meals (soybean, soy protein concentrate, soy protein isolate, canola, canola protein concentrate, flaxseed), two pulse meals (white lupin, pea protein concentrate) and two cereal grain meals (corn gluten, wheat gluten). Protein ADCs were high for wheat gluten meal (99.9%), soy protein concentrate (98.6%), soy protein isolate (97.4%), whole krill meal (96.3%), herring meal (93.3%), soybean meal (92.3%), anchovy meal (92.2%), pea protein concentrate (89.8%), white lupin meal (89.7%), crab meal (89.4%), canola protein concentrate (88.8%) and corn gluten meal (86.3%); mid-range for poultry by-product meal (80.2%) and canola meal (76.0%); and low for shrimp meal (66.7%), hydrolyzed feather meal (62.4%) and flaxseed meal (50.2-55.0%). Energy ADC was high for whole krill meal (96.3%), wheat gluten meal (95.4%), soy protein concentrate (94.9%), herring meal (92.8%), soy protein isolate (92.1%), soybean meal (88.1%) and anchovy meal (86.4%); mid-range for canola protein concentrate (83.3%), corn gluten meal (82.7%), crab meal (82.4%), pea protein concentrate (76.7%) and white lupin meal (75.3%); and low for poultry by-product meal (71.0%), canola meal (60.6%), hydrolyzed feather meal (58.9%), shrimp meal (41.4%) and flaxseed meal (21.2-37.4%). From the protein ADC data, results clearly showed that the basal diet and test feed ingredients were digested independently of one another in nearly all cases, the only exceptions being for those diets containing test ingredients of very high (> 99%, wheat gluten) or very low (< 67%, hydrolyzed feather and flaxseed) protein ADCs. In the case of DE, the basal diet and test feed ingredients were digested independently in all test diets without exception.  相似文献   

13.
Abstract— In vitro enzyme assays are rapid, inexpensive techniques for estimating protein digestibility of feed ingredients. Three assays—the Lazo single-enzyme assay with porcine trypsin; the Hsu multi-enzyme assay with porcine trypsin, α-chymotrypsin, and peptidase; and the Satterlee multi-enzyme assay with porcine trypsin, α-chymotrypsin, peptidase, and bacterial protease—were used to estimate relative protein digestibility (RPD) of selected feed ingredients used in diets for the Pacific white shrimp Penaeus vannamei. Ingredients tested were casein, gelatin, rice bran, shrimp meal, soybean meal, wheat gluten, and six varieties of fish meal. A highly significant, inverse, linear relationship existed between final pH in each of the enzyme assays and in vivo apparent protein digestibility of the ingredient in P. vannamei feeding trials. Ranking of RPD coefficients obtained in the Lazo single-enzyme assay followed closely the ranking of published in vivo apparent protein digestibility coefficients for the same ingredients in P. vannamei digestibility trials. Results indicated that a single-enzyme assay with porcine trypsin identified differences in protein digestibility of feedstuffs in vitro as well as the two multi-enzyme assays tested. The porcine-trypsin, single-enzyme assay appears to be a potentially useful tool for evaluating protein quality and relative protein digestibility of feedstuffs for P. vannamei.  相似文献   

14.
The apparent digestibility coefficients (ADCs) of amino acids (AA), protein, and energy in six feed ingredients (Brazilian fish meal, soybean meal, corn gluten meal, alcoholic yeast, corn, and wheat bran) we evaluated for pacu juveniles. In general, all ingredients showed high digestibility values for all AA, and differences among ADCs of individual amino acid were detected ( P  < 0.01). Corn gluten, soybean, and fish meals had the highest ADCs of AA. The ADCs of protein in fish meal, yeast, and corn gluten meal should not be used as AA digestibility indicators, because those showed differences up to 6.7% between the ADCs of protein and AA. All ingredients had lower ADCs of energy than corn gluten meal ( P  < 0.01). Lysine was the first limiting amino acid in fish meal, corn gluten meal, wheat bran, and corn, and the second limiting amino acid in soybean meal, as methionine was the first limiting amino acid in soybean meal and yeast. However, the soybean meal was the best quality protein source, as it had the highest digestible essential amino acid index. This demonstrated that digestible amino acid values can be used to formulate practical diets for pacu, preventing potential deficiencies or excess that might cause environmental and economic losses.  相似文献   

15.
Abstract— Fisheries by-catch and by-product meals are portrayed as ingredients having a great potential as ingredients in aquaculture feeds. The present study was designed to evaluate the nutritional value of shrimp by-catch meal, shrimp processing waste meal, and two fish meals made from Pacific whiting (meal with and without solubles) for rainbow trout by determining apparent digestibilityof these ingredients and conducting a 12-wk feeding trial with juvenile fish (average initial weight 20 g/fish). Apparent digestibility coefficients (ADCs) for protein in diets containing by-catch and processing by-products were 76% for shrimp by-catch meal, 79% for shrimp processing waste meal, 88% for Pacific whiting meal without solubles, and 92% for Pacific whiting meal with solubles. ADCs for lipid were higher than 94% for all the diets. ADCs for energy were 57% for shrimp by-catch meal, 73% for shrimp processing waste meal, 70% for Pacific whiting meal without solubles, and 73% for Pacific whiting meal with solubles. Growth performance was significantly affected by dietary protein source. Fish fed the shrimp by-catch meal diet had weight gain and feed conversion ratios similar to that of fish fed the control diet with anchovy fish meal. Fish fed diets containing shrimp processing waste and Pacific whiting meal with solubles had significantly lower weight gain and higher feed conversion ratios than the control diet. Growth was significantly lower in fish fed the Pacific whiting meal diet compared to fish fed the anchovy fish meal. The lower growth of fish fed diets containing Pacific whiting meal appeared to be a result of lower feed intake, indicating perhaps a lower palatability of this ingredient. Additional research addressing processing methods, nutritional manipulations, and palatability enhancement is needed to improve potential of some fisheries byproduct meals as ingredients in the diets of rainbow trout.  相似文献   

16.
The ability of frogs to digest dietary nutrients changes with growth, with the animals becoming more or less demanding. The objective of this study was to determine the apparent digestibility coefficients of protein, energy and ether extract of 14 ingredients used in bullfrog diets (spray‐dried blood meal, hydrolysed feather meal, poultry by‐product meal, red blood cell concentrate, tilapia by‐product meal, sardine fishmeal, salmon fishmeal, meat and bone meal, corn gluten meal, soybean meal, corn, wheat bran, soy protein concentrate and soybean oil). A total of 2,325 bullfrogs (Lithobates catesbeianus) in different phases of development were used: early phase (mean weight of 30–50 g), growth phase (80–110 g) and finishing phase (150–200 g). Faeces were collected using the method of dissection. Marked differences in digestibility of the ingredients were observed between the different phases of frog development. Among the ingredients studied, salmon fishmeal and corn gluten meal showed good utilization of the protein (78.9% and 86.7%, respectively) and energy fraction (89.4% and 83.3%, respectively). The salmon fishmeal, poultry by‐product meal, sardine fishmeal, soy protein concentrate, wheat bran and soybean oil exhibited good ether extract utilization (81.2%–92.8%), recommending their use in bullfrog diets.  相似文献   

17.
A feeding trial was conducted to evaluate the efficacy of replacing fish meal (FM) with blood meal (BM), poultry by‐product meal (PBM), meat and bone meal (MBM) and shrimp head meal (SHM), rapeseed meal (RM) and peanut meal (PM) on a digestible basis of crude protein and lysine and methionine in five practical diets for the Pacific white shrimp at the FM levels of 300, 250, 200, 150 and 100 g kg?1 under laboratory conditions. Each of the five experimental diets was hand‐fed to four replicate tanks of shrimp with an average weight of 0.33 ± 0.03 g to satiation at each meal. The shrimp were fed three times a day over a six‐week period. The per cent weight gain of initial body weight (WG%) was significantly lower in shrimp fed 100 g kg?1 FM diet, but the value for hepatosomatic index (HSI) and the level of blood urea nitrogen (BUN) tended to be higher in shrimp fed 100 g kg?1 FM diet than those in shrimp fed other diets. The lowest value for feeding rate (FR) occurred for shrimp fed the basal diet and was significantly lower than that in shrimp fed the FM diets at 100–150 g kg?1. Shrimp fed diets containing 200 g kg?1 or lower FM had significantly lower feed utilization than those fed the 250 g kg?1 FM diet and the basal diet. The protein efficiency ratio (PER) in the shrimp fed the basal diet was significantly higher than in the other FM diets. Decreasing the FM replacement level significantly reduced nutrient digestibility except in the cases of ash and gross energy, but it did not affect the survival, condition factor (CF), body composition, digestive enzyme activity or plasma transaminase activity. The results of the study indicate that feeding a diet formulated on a digestible basis and involving FM replacement with other protein sources at a greater replacement proportion will not produce a level of shrimp growth equal to that achieved by feeding the basal diet.  相似文献   

18.
海水养殖花鲈对几种饲料蛋白原料的表观消化率   总被引：2，自引：1，他引：1  
纪文秀  王岩  唐金玉 《水产学报》2010,34(1):101-107
测定了在室内海水流水系统中养殖的花鲈对7种常用饲料原料,宠物级鸡肉粉(P-PBM)、饲料级鸡肉粉(F-PBM)、血粉(BM)、羽毛粉(FEM)、蚕蛹粉(SWP)、豆粕(SBM)和菜粕(RSM)以及1种混合动物蛋白粉(MM=50%P-PBM+20%F-PBM+20%BM+10%FEM)的干物质、蛋白质和能量表观消化率(ADC)。实验饲料由70%基础饲料(蛋白质含量为42.0%,能量含量为18.9MJ/kg)和30%的待测原料组成。基础饲料和实验饲料中均添加1%(质量分数)的Cr2O3作为外源标记物。饲养实验共进行4周。实验期间每天投饵两次,采用虹吸方法收集粪便。实验结果显示:花鲈对P-PBM、F-PBM、BM、FEM、MM、SWP、SBM和RSM干物质ADC分别为61%～87%,蛋白质ADC为80%～96%,能量ADC为75%～93%。其中,花鲈对SBM的蛋白质ADC最高,对MM的蛋白质ADC最低,对BM的干物质和能量ADC最高,对RSM的干物质和能量ADC最低。  相似文献   

19.
A growth trial and a digestibility trial were conducted to evaluate the efficacy of phytase supplemented to practical shrimp feeds. The 5 weeks growth trial evaluated the effects of phytase supplementation in replete phosphorus (P) diets on the performances and compositions of juvenile Pacific white shrimp, Litopenaeus vannamei. No significant differences were observed in final biomass, final mean weight, weight gain, feed conversion ratio (FCR), protein retention and survival across all the treatments. Shrimp reared on the P deficient diet had significantly higher P retention and lower whole body P levels as compared to shrimp fed the other diets. Copper content in the whole shrimp body was significantly increased in the treatment supplemented with 1,000 IU kg?1 feed phytase. The digestibility trial was conducted to study the combined effects of phytase supplementation levels and diet type (plant‐based versus fishmeal‐based) on apparent digestibility coefficients of Pacific white shrimp, Litopenaeus vannamei. There were no effects of diet type so the data was combined. Phytase incorporation at both 500 and 2,000 IU kg?1 significantly improved protein digestibility, whereas P digestibility was enhanced when 2,000 IU kg?1 phytase was supplemented to the diet. Apparent digestibility coefficients of alanine, arginine, aspartic acid, cysteine, glutamic acid, glycine, histidine, isoleucine, leucine, lysine, methionine, ornithine, phenylalanine, proline, serine, threonine, tyrosine and valine were significantly increased when fed diets contained 500 and 2,000 IU kg?1 phytase supplementation. Results of this work demonstrate that under the conditions of the study growth was not enhanced by phytase supplementation in P replete diets. However, nutrient retention for Cu and digestibility of P, protein and a number of amino acids were enhanced.  相似文献   

20.
A growth trial and a digestibility trial were conducted to evaluate the efficacy of carbohydrase supplemented to practical shrimp feeds. The 5‐wk growth trial investigated the effects of carbohydrase supplementation at 0, 0.01, 0.02, 0.03, 0.04, and 0.05% in soybean‐based diets on the performance of juvenile Pacific white shrimp, Litopenaeus vannamei. No significant differences were observed in final biomass, final mean weight, weight gain, feed conversion ratio, and survival across all treatments. The digestibility trial was conducted to evaluate the effects of carbohydrase supplementation at 0.02%, which is the recommended dose by the company that developed the carbohydrase on apparent digestibility coefficients of dry matter, protein, and energy of Pacific white shrimp. Protein digestibility was significantly improved when fed diets contained 0.02% carbohydrase in contrast with the basal diet. No significant differences were found in apparent digestibility coefficients of dry matter and energy. Based on the positive results on protein digestibility, further research regarding the efficacy of exogenous enzymes and their application is warranted.  相似文献   

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