首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
In this study, we replaced fish meal with peanut meal (PM) in isonitrogenous and isolipidic diets for Pacific white shrimp at inclusion levels of 0, 70, 140, 210, 280 and 350 g kg?1. The diets were hand‐fed to three independent groups of shrimp three times a day over a 6‐week period. Shrimp fed PM diets at a level of 280 g kg?1 or higher had lower per cent weight gain compared with those fed the basal diet, whereas shrimp fed PM diets at 140 g kg?1 or higher had a lower feed utilization and protein efficiency ratio compared with shrimp fed the basal diet. The feeding rate in shrimp fed PM diets at 350 g kg?1 and the survival and protease activity in shrimp fed PM diets at 210 g kg?1 or higher were lower than that in shrimp fed the basal diet. Diets containing 280 g kg?1 or higher of PM caused an increase in the whole‐body moisture content of the shrimp, but decreased whole‐body protein and ash contents compared with the basal diet. Nutrient digestibility was lower or tended to be lower in shrimp fed a PM diet compared with those fed the basal diet. The activities of peroxidase and acid and alkaline phosphatases in plasma decreased with increasing levels of PM inclusion up to 210 g kg?1. Superoxide dismutase activity decreased at dietary PM levels of 280 g kg?1 or higher. Aflatoxin B1 residue in the muscle was not affected by any of the treatments and remained low. The data suggest that up to 140 g kg?1 of PM could be included in practical diets for Pacific white shrimp.  相似文献   

2.
An assessment of the nutritive value of palm kernel meal (PKM) and aflatoxin‐contaminated PKM (obtained by fermenting PKM with Aspergillus flavus) as a dietary ingredient in pelleted feed for tilapia, Oreochromis mossambicus Peters, was carried out in a 12‐week feeding trial. Seven isonitrogenous (40% crude protein) and isoenergetic (15.1 kJ g?1) practical diets were formulated and fed close to apparent satiation to triplicate groups of 12 fish (mean initial weight 8.4 ± 0.1 g). The control diet contained 30% fish meal and 10% soybean meal (SBM) proteins. Four other experimental diets containing 20% and 50% of the SBM protein replaced by either PKM or fermented PKM, respectively, were formulated. Two additional diets containing either PKM or fermented PKM supplemented with a commercial aflatoxin adsorber (0.5% SorbatoxTM) were also formulated. Measured aflatoxin B1 levels in the fermented PKM‐based diets ranged from 75 to 100 µg kg?1 diet. The growth performance and feed utilization efficiency of tilapia fed fermented PKM‐based diets were significantly lower than in fish fed the control diet at all inclusion levels (P < 0.05). Despite a small reduction, weight gains of tilapia fed PKM‐based diets were not significantly different compared with fish fed the control diet. The addition of 0.5% Sorbatox did not produce any beneficial or negative effects to the growth of tilapia. Under the dietary conditions of the present experiment, it was concluded that PKM can substitute up to 50% SBM in practical diets for O. mossambicus without much adverse effect to fish growth. However, when PKM was contaminated with A. flavus, its' incorporation into tilapia diets resulted in growth depression as a result of decreased diet digestibility and also possibly because of the presence of anti‐nutrients found in the contaminated PKM.  相似文献   

3.
Fungal contamination of shrimp feeds affects the shelf life leading to substantial economic losses. Ultrastructural changes in Penaeus monodon sub‐adults fed three different doses (50, 1000 and 2000 ppb) of aflatoxin B1 (AFB1) were studied. At the end of 4 and 8 weeks of experiment, the hepatopancreas of shrimps were observed for ultrastructural changes. The prominent ultrastructural changes in hepatopancreas of the shrimps fed 1000 and 2000 ppb AFB1 were rupture of cell membrane and microvillus border, damage and swelling of mitochondria, fragmentation of endoplasmic reticulum, nuclear vacuolation, chromatin condensation and autophagy. This study helps to decipher the ultrastructural changes and relate the effects on biochemical, pathological, immunological and histological architecture of the shrimps fed AFB1‐incorporated feed. The observed ultrastructural changes could serve as indicators in shrimps exposed to toxicants.  相似文献   

4.
This experiment was conducted to evaluate the effects of dietary lipid sources on the growth performance and fatty acid (FA) composition of juvenile shrimp, Litopenaeus vannamei. Six isoenergetic and isonitrogenous semi‐purified diets containing casein, solvent‐extracted soybean meal and gelatin as protein sources, were supplemented with 60 g kg−1 of lipid sources. The lipid sources included: pollack fish oil (PO), pork lard (PL), soy oil (SO), peanut oil (PN), rapeseed oil (RO) and a mixture of pollack fish oil and soy oil (POSO 1 : 1 w/w). Each diet was fed to juvenile shrimp (0.10 g average weight) four times daily in triplicate tanks to apparent satiation (feeding ratio was about 8%) for 8 weeks. At the end of the experiment, weight gain, specific growth rate and protein efficiency ratio were significantly higher for shrimp fed the diet containing PO and the POSO mixture oil than the other lipid sources. The nutritional values of SO, RO, PN and PL were similar. Shrimp fed on PO, mixture oil of POSO and SO had better survival rates than the other lipid sources, and shrimp fed the PL had the lowest survival rate. There were significant differences in lipid contents of whole body and hepatopancreas amongst the dietary treatments; however, lipid contents of tail muscle were not significantly affected by the dietary lipid sources. Shrimps fed POSO diet had higher protein content in whole body than those fed the other lipid sources, and shrimp fed PO diet had highest crude protein content of the tail muscle. A high correlation was found between dietary FA composition and FA composition of whole shrimp. FA composition of the whole body was generally affected by dietary lipid sources, especially dietary unsaturated FA.  相似文献   

5.
An 8‐week feeding trial was conducted to evaluate the effects of dietary aflatoxin B1 (AFB1) on growth performance, haematological parameters and histological changes in juvenile Pacific white shrimp, Litopenaeus vannamei. Six practical diets (455 g kg‐1 protein, 78 g kg‐1 lipid) with different levels of AFB1 (0, 25, 50, 100, 500, 1000 μg kg?1) were formulated. Each diet was fed to triplicate groups of shrimps (initial weight: 0.52 g). The results showed that shrimp fed with control diet (0 μg kg?1 AFB1) had significant higher weight gain (WG) and specific growth rate (SGR) than other groups. However, there were no significant differences in feed efficiency (FE) or hepatosomatic index (HSI) among all groups. Compared to the control diet, AFB1 supplementation significantly changed the activities of shrimp serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), total antioxidant capacity (T‐AOC) and glutathione S‐transferase (GST) and the content of cholesterol (CHO). Histological damages were identified in the hepatopancreas of shrimp when dietary AFB1 level was over 107.6 μg kg?1. Based on this study, it was concluded that the AFB1 level in Pacific white shrimp diet should be <38.1 μg kg?1.  相似文献   

6.
Toxicity of aflatoxin B1 (AFB1) was investigated in juvenile hybrid sturgeon Acipenser ruthenus ♂ × A. baeri♀, an important coldwater finfish farmed in China and other countries. Seven experimental diets (Diet A–G) containing different levels of AFB1 (0, 1, 5, 10, 20, 40 and 80 μg kg?1 diet) were fed to juvenile sturgeon weighing 10.53 ± 0.17 g kg?1 to determine its effect on survival, growth, feed consumption, hematocrit, liver histology as well as muscular and hepatic toxin accumulation. The experiment lasted for 35 days and was conducted in two periods of 25 and 10 days each. No external changes or unusual behaviour was observed in the fish fed diets with AFB1. Mortality was observed in fish fed with highest levels of AFB1 (80 μg kg?1– Diet G) from day 12 onwards. After 25 days, fish fed the diet of 80 μg AFB1 kg?1 showed significant lower survival (50 ± 5.77%) followed by those fed 40 μg AFB1 kg?1 diet (80 ± 5.77%) and 20 μg AFB1 kg?1 diet (86.66 ± 3.33%). No significant difference was observed in specific growth rate (SGR) or hepatosomatic index (HSI) between groups. Hematocrit was significantly higher in the fish fed the diet of highest AFB1. The fish were weighed at day 25 in some treatments (Diets F and G) because of high mortality. However, feeding was continued for another 10 days to observe mortality or behavioural changes if any in the other groups. After 35 days, survival in the fish fed Diet F (40 μg AFB1 kg?1) was 40% and those fed Diet E (20 μg AFB1 kg?1) was 36.2%. Significant histopathological changes including nuclear hypertrophy, hyperchromasia, extensive biliary hyperplasia, focal hepatocyte necrosis and presence of inflammatory cells were observed in the liver of fish fed high levels of aflatoxin (40 and 80 μg kg?1). AFB1 accumulation in fish muscle and liver increased with increased dietary AFB1 levels. It could be confirmed that 10 μg AFB1 kg?1 diet was the maximum allowable level in hybrid sturgeon diet.  相似文献   

7.
A growth trial was conducted to determine the effects of inclusion of whole shrimp floc or floc fractions to a control diet on growth and survival of shrimp (Litopenaeus vannamei). The floc sample was collected from marine shrimp culture tanks and partially fractionated by extraction with water, acetone and hexane. A series of diets was manufactured by inclusion of whole floc (intact or ground), each of the fractions or their combination to a control diet. These diets were fed to shrimp (approximately 1.0 g) in an indoor laboratory under flow‐through conditions for 8 weeks. It was found that addition of whole floc (200 g kg?1) or floc fractions (24–200 g kg?1) to the control diet improved (P < 0.05) shrimp growth rate without affecting (P > 0.05) shrimp survival (>81.3%). Although inclusion of whole floc reduced the crude protein and crude fat contents and gross energy of the control diet, shrimp fed the whole floc‐supplemented diets obtained the highest (P < 0.05) growth rates (1.01 and 1.03 g week?1) among the shrimp fed the 11 tested diets including two control (0.81 and 0.85 g week?1), two commercial (0.45 and 0.71 g week?1) and five floc‐fraction‐added (0.91–1.00 g week?1) diets. Many bioactive compounds in the floc that possibly affected shrimp growth were also analysed and quantified.  相似文献   

8.
Six diets were formulated with vitamin B6 levels (2.6, 32.7, 54.8, 90.7, 119.6 and 247.4 mg kg−1, dry diet) to determine the requirement for juvenile Pacific white shrimp, Litopenaeus vannamei. Triplicate groups of 40 juvenile shrimp (approximately 1.0 g) were provided four times each day to apparent satiation (8 weeks). Weight gain (WG), specific growth rate, feeding efficiency, protein efficiency ratio (PER) and protein productive value of the shrimp were significantly influenced by the vitamin B6 levels. No significant differences in whole‐body and muscle composition, except for dry matter and protein contents in whole body. Vitamin B6 concentration in the hepatopancreas significantly increased with the dietary vitamin B6 level increasing from 2.6 to 32.7 mg kg−1. High‐density lipoprotein cholesterol in the haemolymph improved with the dietary vitamin B6 levels increasing from 2.6 to 90.7 mg kg−1 diet and no significant differences in low‐density lipoprotein cholesterol, cholesterol, glucose and total protein concentrations. Aspartate aminotransferase, alanine aminotransferase, superoxide dismutase, catalase and lysozyme in the haemolymph were significantly influenced by dietary vitamin B6 levels. The optimal dietary vitamin B6 requirements estimated using a two‐slope broken‐line model based on WG and SGR and an exponential model based on the vitamin B6 concentration in the hepatopancreas were 110.39, 110.08 and 167.5 mg kg−1, respectively.  相似文献   

9.
This article elucidates the effect of crude dietary aflatoxin B1 (AFB1) on the stability of the lysosomal membrane in tilapia (Oreochromis mossambicus), and the analysis was made at the biochemical and cellular level. The liver lysosomal acid phosphatase activity was used to evaluate the functional integrity of the lysosome. Three experimental groups were fed on diets containing 0.375, 2.5 and 6 mg kg?1 of AFB1 for a time period of 6 weeks, whereas a fourth group fed on the semi‐purified diet formed the control. Significant changes were observed in the stability of the lysosomal membrane in aflatoxin exposed groups. This is the first report, so far, of changes induced by AFB1 on the stability of lysosomal membrane in tilapia (O. mossambicus).  相似文献   

10.
Total replacement of fishmeal using marine co‐product meals in the diets for white shrimp Litopenaeus vannamei and its effects on growth, feed utilization and muscle HUFA and sterol composition were assessed in a 45‐day feeding trial with juvenile shrimp (0.32 g mean initial weight). Eight dietary treatments were tested: a control diet containing fishmeal (FM), a commercial shrimp diet as external reference and six diets where the FM in the control diet was totally replaced by pen shell scallop viscera (Pinna rugosa), squid viscera (Dosidicus gigas) or whole chub mackerel (Scomber japonicus) meals, produced by two methods: (i) cooking followed by grinding and drying and (ii) grinding followed by drying. Survival in all treatments was above 92%, except in the commercial diet (77%). The growth response, feed utilization and chemical composition of shrimp varied among the treatments and were affected in different ways by the by‐products and the meals preparation process. Growth and feed intake were significantly higher in shrimp fed diets containing cooked‐dried squid and pen shell scallop viscera meals, and whole mackerel meal produced by grinding followed by drying. Muscle fatty acid profiles were improved for human consumption when these ingredients were used, compared with the diets containing FM.  相似文献   

11.
This study investigated the effectiveness of dietary supplementation of astaxanthin (Ax) from the Haematococcus pluvialis on growth, survival, and pigmentation in Pacific white shrimp. Ten test diets were processed to contain five levels of Ax (25, 50, 75, 100, and 150 mg/kg as fed basis) by adding the natural or synthetic Ax to a basal diet containing no Ax. Each diet and a commercial shrimp feed were fed to four replicate tanks of shrimp (12 shrimp/tank) for 8 wk. Neither the natural nor synthetic Ax affected shrimp growth or survival. After cooking, shrimp fed the diets containing the natural Ax exhibited a strong red color, compared to the light pink color of shrimp fed the remaining diets. Colorimetric readings and Ax content in cooked shrimp demonstrated that the natural esterified Ax had greater pigmentation efficiency than synthetic free Ax (P < 0.05). The Ax contents in shrimp tail muscle demonstrated significant correlation with the levels of dietary Ax. The supplementation level of the natural Ax for optimum pigmentation efficiency is in a range of 75–100 mg/kg diet. The Ax product used in this study contained only a small amount (ca. 5.0%) of other carotenoids, indicating that the high pigmentation efficiency was mainly due to algal esterified Ax.  相似文献   

12.
An 8‐week study was conducted to explore the results of Macsumsuk® as a feed additive on the stress tolerance and growth of Litopenaeus vannamei in 15 culture tanks of 36 L each. Three hundred shrimp averaging 0.1 ± 0.01 g were fed with five isonitrogenous (48.38 ± 0.38% CP) diets (in triplicate groups) containing kaolinite (Macsumsuk®) at 0%, 0.3%, 0.6%, 1.2% and 2.4%, namely Mk0, Mk0.3, Mk0.6, Mk1.2 and Mk2.4. Specific growth rate (SGR) and weight gain (WG) of shrimp fed diets Mk1.2 and Mk2.4 were significantly better than those of shrimp fed diet Mk0 (p < .05). However, SGR and WG of shrimp fed diets Mk0.6, Mk1.2 and Mk2.4 were not significantly different. Protein efficiency ratio (PER) and feed efficiency (FE) of shrimp fed diets Mk1.2 and Mk2.4 were significantly better than those of shrimp fed diets Mk0, Mk0.3 and Mk0.6. Furthermore, the survival of shrimp fed diet Mk2.4 was significantly lower than that of shrimp fed diet Mk0.6 (p < .05). Cumulative mortality of shrimp fed diet Mk1.2 was significantly lower than that of shrimp fed diet Mk0 at 1–1.5 hr post‐stress to low dissolved oxygen (from 6.1 mg/L to 2.9 mg/L) and 4–5 hr post‐stress to low salinity (from 32‰ to 1‰) (p < .05). The optimum dietary Macsumsuk® level for juvenile L. vannamei was determined as 1.97% by the polynomial regression analysis of weight gain.  相似文献   

13.
This study was conducted to evaluate the effects of supplementation of crystalline methionine or coated methionine supplemented in diets of Pacific white shrimp (Litopenaeus vannamei) on growth performance and feed utilization. Five iso‐nitrogen and iso‐caloric diets were prepared in which diets were supplemented with cellulose‐acetate‐phthalate (CAP), tripalmitin‐polyvinyl alcohol (TPA), acrylic resin (RES) coated l ‐methionine, hydroxyl‐methionine calcium (MHA) and crystalline l ‐methionine diet (MET, control), respectively. After 7 weeks, shrimp (0.81 ± 0.01 g in initial body weight) weight gain fed with MET and RES diets were significantly higher than that of the others (P < 0.05), while feed conversion ratio of shrimp fed with RES was significantly lower than the others (P < 0.05). Crude protein (as wet weight basis) in whole body of shrimp fed the RES diet was markedly higher than the others (P < 0.05). Methionine contents in muscle of CAP and MHA groups were significantly higher than those of MET group (P < 0.05). Apparently digestibility for essential amino acid of MET group was the highest except methionine. In the present study, RES coating methionine appeared to effectively improve feed protein utilization and enhance growth performance of Pacific white shrimp fed with low fishmeal practical diet.  相似文献   

14.
Jatropha curcas (L.) is a multipurpose and drought‐resistant tree, widespread throughout the tropics and subtropics. Its seeds are rich in oil and protein (contains 600–660 g kg?1 crude protein similar to fish meal). It is being promoted as a biofuel plant. Jatropha kernel meal obtained after oil extraction is an excellent source of protein. However, presence of toxic and antinutritional constituents restricts its use in fish and shrimp feed. An 8‐week experiment was conducted to evaluate the nutritional quality of the detoxified Jatropha kernel meal (DJKM) in white leg shrimp (Litopenaeus vannamei). Shrimp (60) with an initial average body weight of 4.46 ± 0.64 g were randomly distributed into three treatments with four replicates and fed isonitrogenous and isoenergetic diets (crude protein 350 g kg?1, crude lipid 90 g kg?1): Control (fish meal‐based protein), JC25 and JC50 (25% and 50% of fish meal protein replaced by DJKM). Higher (P < 0.05) body mass gain, specific growth rate and metabolic growth rate were observed in DJKM‐fed groups than in Control group. However, lower (P > 0.05) feed conversion ratio was observed in DJKM‐fed groups, while protein efficiency ratio exhibited an opposite trend. Protein, ash and gross energy content of the whole shrimp body were higher (P < 0.05) in DJKM‐fed groups compared to Control group. Moisture and lipid content of the whole shrimp body did not differ significantly among the three groups. Cholesterol level in plasma was highest (P < 0.05) in the Control group, followed by JC25 and JC50 groups; all being significantly different. In conclusion, DJKM is a promising fish meal replacer in shrimp diets.  相似文献   

15.
Juvenile (5.5–5.7 g) white leg shrimp were exposed to mycotoxin in one indoor trial by feeding fumonisin B1 (FB1) at levels from 0.2 to 2.0 μg g?1 FB1 for 30 days. Shrimp growth was affected after exposure to more than 0.6 μg g?1 FB1. Soluble muscle protein concentration decreased, and changes in myosin thermodynamic properties were observed in shrimp after 30 days of exposure to FB1. Marked histological changes in tissue of shrimp fed a diet containing FB1 at 2.0 μg g?1 were also observed. Shrimp fed diets containing more than 0.6 μg g?1 FB1 showed greater decrease in shear forces after 12 days of ice storage.  相似文献   

16.
An 8‐week feeding trial was conducted to evaluate the optimum dietary protein‐to‐energy (P/E) ratio in juvenile whiteleg shrimp, Litopenaeus vannamei. Six diets were formulated with two protein levels (30% and 35%) and three digestible energy levels (16, 17.5 and 19 kJ/g diet) at each protein level (30P16, 30P17.5, 30P19, 35P16, 35P17.5 and 35P19). Fifty shrimp averaging 0.97 ± 0.03g (Mean ± SD) were randomly distributed in biofloc tanks and fed one of the experimental diets. Weight gain (WG), specific growth rate (SGR) and feed efficiency (FE) of shrimp fed the 35P17.5 diet were significantly higher than those of shrimp fed 30P16, 30P17.5 and 30P19 diets (< .05). Results for non‐specific immune responses showed that diet 35P17.5 caused higher lysozyme activity in shrimp comparing to lower protein diets. Thiobarbituric acid reactive substances (TBARS) of plasma were lower for shrimp fed on diets consisting of higher protein and energy levels than shrimp fed on the 30P19 diet. Analyses of digestive enzyme activities showed higher trypsin activities for shrimp fed on 35P17.5 and 35P19 diets comparing to 30P16 and 30P17.5 diets. Also, hepatopancreatic lipase activity of shrimp fed 35P16, 35P17.5 and 35P19 diets were significantly higher than those of shrimp fed the other diets. In conclusion, based on the results for growth performance, biochemical parameters, immune responses, oxidative stress and enzyme activities, 35% protein and 17.5 kJ/g digestible energy (35P17.5) could be considered as the optimum protein‐to‐energy ratio in the diet of juvenile whiteleg shrimp reared in a biofloc system.  相似文献   

17.
Channel catfish Ictalurus punctatus (initial weight: 6.1 g/fish) were fed eight diets containing the mold Fusarium moniliforme-cultured corn supplying 0.7, 2.5, 5, 10, 20, 40, 80, or 240 mg of the mycotoxin, fumonisin B1 (FB1)/kg diet under laboratory conditions for 12 wk. Fish fed diets containing FB1 levels of 40 mg/kg and above showed reduced growth, feed consumption, and feed efficiency, but fish fed FB1 concentrations of 20 mg/kg and below did not. The minimum level of FB1 that depressed growth appeared to be between 20 and 40 mg/kg. Hematocrit was significantly lower for fish fed diets containing 80 and 240 mg FB,/kg than for fish fed diets containing lower levels of FB1. Fish fed diets containing 40 mg FB1kg and above had increased liver glycogen, increased vacuolation in nerve fibers, and perivascular lymphohistiocytic investment in the brain compared to fish fed diets containing lower levels of fumonisins. Results from this study indicate that FB1 levels below 20 mg/kg diet are not a problem in commercial catfish feeds. However, it is prudent to screen for fumonisins in feed ingredients.  相似文献   

18.
A 14‐wk feeding trial was carried out to evaluate the optimum dietary riboflavin (vitamin B2) level in juvenile sea cucumber, Apostichopus japonicus. A total of 360 sea cucumbers averaging 1.49 ± 0.07 g (mean ± SD) were randomly distributed into 18 rectangular plastic tanks, and each tank was then randomly assigned to one of three replicates of six diets containing 0.29 (B20), 4.22 (B24), 8.93 (B29), 17.9 (B218), 56.7 (B257), and 577 (B2577) mg riboflavin/kg diet. At the end of 14 wk of feeding trial, average weight gain (WG) of sea cucumbers fed B29, B218, B257, and B2577 diets were significantly (P < 0.05) higher than that of animals fed B20 diet. WG of sea cucumbers fed B218, B257, and B2577 diets were significantly higher than those of animals fed B20 and B24 diets. Specific growth rate of sea cucumbers fed B29, B218, B257, and B2577 diets were significantly higher than those of animals fed B20 and B24 diets. Feed efficiency of sea cucumbers fed B29, B257, and B2577 diets were significantly higher than those of animals fed B20 and B24 diets. Although significant differences were recorded in proximate composition of sea cucumbers fed the experimental diets, no clear trends were observed. The ANOVA test suggested that the optimum dietary riboflavin level in sea cucumber could be 17.9 mg/kg diet but broken‐line analysis of WG indicated a level of 9.73 mg riboflavin/kg diet. Therefore, these results may indicate that the optimum dietary riboflavin level in sea cucumber could be higher than 9.73 mg/kg diet but lower than 17.9 mg/kg diet.  相似文献   

19.
A 4‐week feeding trial was conducted to determine the effects of oxidized fish oil (OFO, POV: 234.84 meq kg?1) on growth performance and oxidative stress of Litopenaeus vannamei. Five diets containing various OFO levels (0, 25, 50, 75 and 100 g kg?1) with the same dietary lipid level were fed to L. vannamei. The results showed that the body weight gain and the specific growth rate of the shrimp fed with 50, 75 and 100 g kg?1 of OFO diets decreased significantly (< 0.05), whereas the hepatosomatic index increased significantly (P < 0.05). The malondialdehyde concentrations in the serum and muscle of the shrimp fed with 50, 75 and 100 g kg?1 of OFO diets were significantly higher than that of the shrimp fed with fresh fish oil (P < 0.05). The total antioxidant competence decreased significantly compared with the control group. Therefore, dietary OFO affects the growth performance and increases the oxidative stress of shrimp.  相似文献   

20.
Two growth trials and a physiology assessment were conducted to evaluate three non‐genetically modified (GM) soybean cultivars as ingredients in practical diets for Pacific white shrimp, Litopenaeus vannamei. In addition, a commercially available fermented yeast product was evaluated as dietary supplement. For the growth trials (46 and 35 days, respectively, for trials 1 and 2), the basal diet was primarily composed of soybean meal (SBM), fishmeal (FM), whole wheat, corn protein concentrate, poultry meal (PM, pet food grade) and corn starch. Non‐GM cultivars were processed with novel methodologies to produce Navita? ingredients (N1, N2 and N3) which were incorporated at low (L) or high (H) levels into the experimental diets, in partial replacement of FM and full replacement of conventional SBM. The last two formulations incorporated the fermented yeast for a total of nine experimental diets (Table 1 ). Results from the growth trials indicate that shrimp fed diet 5 (HN2) exhibited significantly lower (< .05) weight gain as compared to shrimp fed diets 1 and 2 (basal and LN1, respectively) in trial 1, as well as compared to animals fed diets 1, 2, 3 and 8 (basal, LN1, HN1 and basal + yeast) in trial 2. The feed conversion ratio significantly increased for shrimp fed diet 5, in contrast with shrimp fed diets 1, 2, 3 and 8 in trials 1 and 2, as well as compared to shrimp fed diets diet 6 (LN3) in trial 2. For the physiological assessment (stress and immune responses), only the effects of diets 1, 3, 8 and 9 (basal, HN1, basal + yeast and HN1 + yeast, respectively) were investigated. Granular cell counts were significantly higher for shrimp fed the yeast‐containing diets. Haemolymph glucose and haemolymph packed cell volume were significantly reduced for shrimp fed diets 3, 8 and 9. No significant differences were observed in total haemocyte counts, hyaline cells counts, semi‐granular cells counts, haemolymph protein, haemocyte phagocytic capacity and haemocyte respiratory burst activity. Results of this work indicate that selective soy breeding technology coupled with novel processing options has the potential to increase the nutritional value of conventional SBM for shrimp feeds. Trends on immune responses were more difficult to elucidate possibly due to the limited length of the feeding trial.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号