Effect of dietary pigment on growth performance and disease resistance in black tiger shrimp post larva (Penaeus monodon, Fabricius)

Effects of dietary pigment on survival and disease (white spot syndrome virus: WSSV) resistance in black tiger shrimp post larva (Penaeus monodon, Fabricius) (PL15) for a 30-day period were studied. The results showed that not only was mean survival of black tiger shrimp (PL15) fed with supplementation of Lucarotene or Betatene at 125 mg/kg diet significantly higher (P<0.05) but also the body color was increased. There were no effects of dietary pigment on mean weight, percent weight gain and WSSV resistance. However, mean WSSV resistance of black tiger shrimp (PL15) fed diet containing Lucantin pink 50 mg/kg diet, Spirulina 30 g/kg diet or Betatene 125 mg/kg diet was higher than that of control

Effects of Thai medicinal plants on pathogenic bacterial, growth performance, health condition and disease resistance in black tiger shrimp (Penaeus monodon Fabricius)

Chemical analysis of turmeric (Curcuma longa) extracts using TLC/densitometry, showed an extract contain 21.57%w/w of three important curcuminoids: curcumin, desmethoxycurcumin and bisdesmethoxycurcumin. GC and MS were used to analyze volatile oils. Aromatic turmerone, α-turmerone and zingiberene were also obtained. Qualitative and quantitative analyses alcoholic extract of Andrographis paniculata using TLC, revealed that the extracts contain three important compounds in total lactone of 30.49% w/w. There are andrographolide,14-deoxy-11-12-didehydroandrographolide and neoandrographolide. TLC-chromatogram of Clinacanthus nutans extract after reacted with anisaldehyde/sulfuric acid showed a 9 key compounds, while preliminary neutralization test of the compounds revealed that there were active compounds against HSV-1 virus. In vitro efficacy test revealed that Curcuma longa and Andrographis paniculata extracts at 250 and 1,500 mg/L could eradicate 15 isolates of Vibrio spp. which were isolated from infected shrimps. Effects of medicinal plant extracts incorporated into the diet on shrimp immune responses were investigated. Shrimp fed diet containing Clinacanthus nutans extract at 20 mg/kg of diet had good growth, FCR and immune responses. The shrimp that were fed diet containing Curcuma longa extracts at 25 mg/kg of diet for 7-14 days showed high resistance to Vibrio harveyi. Likewise, the shrimp fed Andrographis paniculata extract at 25 mg/ kg of diet for 14 days had a higher resistance to WSSV. Incorporating the medicinal extracts at higher levels resulted in reduction in diet palatability which consequently had an effect on a decrease in growth, immune responses and resistance to bacterial and WSSV infection

An analysis of biological characteristics of Macrobrachium rosenbergii (de Man) in relation to pond production and marketing in Thailand

Data on production and marketing of giant freshwater prawn were collected over a 7-month grow-out period through collaboration with a medium-sized commercial prawn farm in central Thailand. Juvenile prawns with an average weight of 4.2 g were stocked at a density of 6 prawns/m2 in three 0.5-ha earthen ponds. Average growth rate determined during the first 3 months of the grow-out period was 0.4 g/prawn per day; prawns of marketable size were harvested selectively during the remaining 4 months of the rearing period, resulting in a total accumulated yield of 1.3 tonnes/ha with an average prawn weight of 32 g and 60% survival. As different sexes and sizes of prawns were sold at different prices, the harvests were customarily sorted into several categories: large, medium, and small males, long-clawed males, soft shells, females with eggs, females without eggs, and terminal males. The total weight and number of prawns recorded for each of these categories showed that the female to male ratios were 1.6:1 and 4:1 by weight and number, respectively while the ratio of short to long-clawed males was 3:1 by weight and 4:1 by number. Four percent of the marketable population was termed "soft shells" and 64% of the females bore eggs. The ratio of head weight to tail weight of marketable prawns varied substantially among the different categories: 1.0:1 for females, 2.5:1 for long-clawed males, and 1.6:1 for short-clawed males. Females predominated in the first and second 1.5-month harvest periods while males predominated in the final 1.5 months of the harvest. The economic yield of prawn culture was not only determined by the biomass, but also by the population structure of the various biological categories and the harvest season.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/27065/1/0000055.pd

Effects of ochratoxin A and deoxynivalenol on growth performance and immuno-physiological parameters in black tiger shrimp (Penaeus monodon)

Ochratoxin A (OTA) and deoxynivalenol (DON), naturally occurring contaminants of animal feed, have been implicated in several mycotoxicoses in farm livestock but there is little information on their toxicity in aquatic invertebrates. Therefore, in the present study an 8-week feeding trial was conducted on black tiger shrimp (Penaeus monodon) to assess the effects of OTA and DON on growth performance, haemolymph parameters and histopathology of shrimp. Results showed that feed supplemented with DON caused no effect on growth or survival rate of the shrimp. However, shrimps fed DON feed diet with 1,000 ppb showed significantly higher growth performance. No significant difference in total haemocyte counts (THC) was found in shrimp fed mycotoxins-supplemented feed. Feeding high level of OTA (1,000 ppb) caused a decrease in phenoloxidase (PO) activity. Although no histopathological change was observed, decrease in serum alkaline phosphatase (ALP), serum glutamic-oxaloacetic transaminase (SGOT) and serum glutamic-pyruvic transaminase (SGPT) levels in shrimp fed OTA or DON indicated that mycotoxin may impair the functioning of hepatopancreatic cells. Since no adverse effect occurred with the highest levels of OTA and DON (1,000 and 2,000 ppb, respectively) on haemolymph parameters and no residue was detected at the completion of the 8-week feeding period, it can be concluded that shrimp feeds occasionally contaminated with OTA or DON have no negative impact on the shrimp culture industry

Effect of diets containing a purified soybean trypsin inhibitor on growth performance, digestive proteases and intestinal histology in juvenile sea bream (Sparus aurata L.)

Juvenile sea bream were fed on diets containing 0.0, 2.0 or 4.0 g/kg of a soybean trypsin inhibitor (SBTI) for 30 days. The growth performance, total protease activity and intestinal histology were studied after 0,15 and 30 days of dietary treatment. No signi¢cant di¡erences were found in the weight gain, speci¢c growth rate (SGR) and feed conversion rate in fish fed on inhibitor-supplemented diets when compared with those fed on an inhibitor-free diet. Only the SGR at day 15 decreased signi¢cantly with protease inhibitor inclusion, although this effect was not observed at day 30. In relation to proteolytic activity at day 15, the total protease activity in the distal intestine decreased in ¢sh fed on inhibitor-supplemented diets. Zymograms of these extracts showed that the SBTI reduced the intensity of some proteolytic fractions in the distal intestine. A noticeable reduction in the protease activity of the intestinal content in fish fed onthe highest level of soybean inhibitor (4.0 g/kg) was also observed. However, at day 30, the inhibition e¡ect on these active bands was not detected, and the total protease activity was similar to that in ¢sh fed on an inhibitor-free diet. Histological examination revealed no perceptible differences in the intestinal structure between any of the diet groups. In addition, all ¢shweremaintained under experimentation for 10 more days and fed on an inhibitor-free diet to determine whether the possible effects caused by the protease inhibitor could be reverted.The administration of SBTI-supplemented diets did not affect sea bream growth performance or intestine histology after 30 days, and only a decrease in the total alkaline protease activity was found at day 15

Efficacy of insect larval meal to replace fish meal in juvenile barramundi, Lates calcarifer reared in freshwater

The present experiment was conducted to evaluate the efficacy of dietary protein from black soldier fly, Hermetia illucens, larval meal (BSFL) to replace fish meal (FM) protein in juvenile barramundi, Lates calcarifer. Larvae of black soldier fly were fed with the underutilised crop, sesbania, Sesbania grandiflora. Five isonitrogenous (44% crude protein) and isocaloric (16.0 kJ available energy/g) experimental diets were formulated to replace FM using processed BSFL meal at 0 (control), 25% (BSFL25), 50% (BSFL50), 75% (BSFL75) and 100% (BSFL100). Data for proximate and amino acid analysis suggested BSFL meal as an inferior protein ingredient than FM, but parallel to soybean meal. At the end of 8 weeks of fish feeding trial, there were no significant differences in the average weight gain (WG) and specific growth rate among the group of fish-fed control, BSFL25 and BSFL50 diets (P < 0.05). Although numerical differences were recorded in the fish whole-body proximate composition, crude protein and moisture content were not much affected by the different dietary treatments. Essential amino acids including arginine, histidine, lysine and methionine were found to be higher in the whole body of fish-fed BSFL100 diet. Broken line regression analysis of average WG showed an optimum FM replacement level of 28.4% with BSFL meal. Therefore, the present experiment clearly demonstrates that the maximal dietary inclusion level of BSFL meal as FM protein replacer for the optimum growth of juvenile barramundi reared in freshwater could be greater than 28.4% but less than 50%, without any adverse effects on the fish whole-body proximate and amino acid composition

Investigation of highly unsaturated fatty acid metabolism in the Asian sea bass, Lates calcarifer

Lates calcarifer, commonly known as the Asian sea bass or barramundi, is an interesting species that has great aquaculture potential in Asia including Malaysia and also Australia. We have investigated essential fatty acid metabolism in this species, focusing on the endogenous highly unsaturated fatty acid (HUFA) synthesis pathway using both biochemical and molecular biological approaches. Fatty acyl desaturase (Fad) and elongase (Elovl) cDNAs were cloned and functional characterization identified them as ∆6 Fad and Elovl5 elongase enzymes, respectively. The ∆6 Fad was equally active towards 18:3n-3 and 18:2n-6, and Elovl5 exhibited elongation activity for C18-20 and C20-22 elongation and a trace of C22-24 activity. The tissue profile of gene expression for ∆6 fad and elovl5 genes, showed brain to have the highest expression of both genes compared to all other tissues. The results of tissue fatty acid analysis showed that the brain contained more docosahexaenoic acid (DHA, 22:6n-3) than flesh, liver and intestine. The HUFA synthesis activity in isolated hepatocytes and enterocytes using [1-14C]18:3n-3 as substrate was very low with the only desaturated product detected being 18:4n-3. These findings indicate that L. calcarifer display an essential fatty acid pattern similar to other marine fish in that they appear unable to synthesize HUFA from C18 substrates. High expression of ∆6 fad and elovl5 genes in brain may indicate a role for these enzymes in maintaining high DHA levels in neural tissues through conversion of 20:5n-3