Apparent digestibility coefficients and nutritional value of Iranian cottonseed meal varieties for rainbow trout (Oncorhynchus mykiss)

Three different varieties of cottonseed meal (CSM) were evaluated to measure the apparent digestibility coefficient (ADC) of the nutrients using chromic oxide (Cr2O3) as an indigestible marker. Five experimental diets were prepared and mixed with 1% of Cr2O3, 2% of mineral and vitamin each of which were premixed. Diet 1 was used as the control diet. Diets 2, 3, 4 and 5 were formulated using 70% of the control diet together with 30% of each of the cottonseed meal Pak (CSMP), cottonseed meal Sahel (CSMS), cottonseed meal Akra (CSMA), and soya bean meal (SBM), respectively, in three replications. The ADC of the three CSM varieties was measured to be 53.8-62.7%, 60.2-66.6% and 75.6-82.4% for dry matter, fat and crude protein, respectively. Survival rate for all fishes used in this study was more than 98%. Fishes fed with the CSM diets were not significantly different compared with those fed with the SBM diet in terms of survival rate (p>0.05). Apparent protein digestibility of CSMP and CSMS showed no significant difference with SBM (p>0.05). Therefore, it could be concluded that two kinds of CSM could be used as a replacement for SBM in rainbow trout as a protein source

Probiotic administration of Litopenaeus vannamei: Is there any negative effect on the fatty acid profile of meat?

It has been found that appropriate probiotic applications increased growth performance and disease resistance in shrimp. Bacillus subtilis has been suggested as a potent probiotic in improving growth performance and enhancing immune response in white shrimp, Litopenaeus vannamei. The aim of this work was to evaluate the possible effect of B. subtilis administration on the meat fatty acid profile of white shrimp, L. vannamei. Two groups of shrimps received B. subtilis strains L10 and G1 from the B. subtilis-supplemented feed (10^5 and 10^8 CFU g^-1) while two other groups received it from the rearing water (10^5 and 10^8 CFU ml^-1). One group received no B. subtilis and served as control. According to the results, there was no significant difference between the muscle fatty acid profiles of shrimps administrated by probiotic and control group. This study showed that B. subtilis administration, in either diets or water, did not have any negative effect on fatty acid profiles of L. vannamei meat

Solderability of Sn-0.7Cu/Si3N4 lead-free composite solder on Cu-substrate

AbstractReinforcing high performance ceramic particulates is an effective approach to improve solderability of lead-free Sn-0.7Cu solder. Various weight percentage compositions (0.5, 1.0, and 1.5) of Silicon Nitride (Si3N4) reinforced in Sn-0.7Cu solder were developed using powder metallurgy (PM) routes to investigate their solderability properties on copper (Cu) substrate. The solderability performances of the new composite solder will be determined and analyzed based on their contact angles on Cu substrate, including interface intermetallic compound (IMC) layer thickness and IMC phases formed for different Si3N4 ratios. Results also show an improvement in solderability of the Sn-0.7Cu/Si3N4 composite lead-free solder with optimum wettability achieved by 1.0wt.% Si3N4. The minimal average decrease in IMC layer thickness and the formation of the different shaped of scallops figuring the IMC layer were observed. X-ray diffraction (XRD) also revealed the decreasing peak intensity of Cu6Sn5 phases with Si3N4. Overall, the entire range of composition of Si3N4 into Sn-0.7Cu monolithic solder use in this study indicated an enhancement of solderability performances on Cu-substrates

Variation of growth and proximate composition in Portunus pelagicus juveniles fed with selected feeds in recirculating aquaculture system (RAS)

Aim: The experiment was conducted to determine the suitability of using scad fish, Acetes shrimp and common squid for the direct and indirect application as diets for the juvenile rearing of the blue swimming crab Portunus pelagicus. Methodology: A total of 54 crab juveniles with an initial weight of 2.46 ±0.94 g were randomly stocked in triplicate at 6 crabs per 60 l tank (0.26 m²) experimental units and fed twice daily with three different types of feed namely scad fish, squid tissue and frozenAcetesshrimp foraperiodof31days. Results: At the end of the trail, ammonia and nitrite-nitrogen compound were significantly higher in Acetes shrimp fed group. It is found that final body weight (g) of P. pelagicus was significantly higher when fed with squid, however no significant differences were noticed between scad fish and Acetes shrimp fed groups. The whole body proximate composition was similar in all the diet fed individuals except the level of lipid which was higher in squid compared to scad fish and Acetes shrimp. Significantly (p<0.05) better food conversion ratio (FCR) was observed in juvenile crab fed with squid even though scad fish possessed the highest crude protein of 83.33%. Interpretation: Overall, the results suggested that squid meal could be recommended for P. pelagicus juvenile culture. Hence, squid meal may be incorporated in crab artificial diet as protein source to attain better survival and growth

Ontogenic development of the mouth and digestive tract in larval Malaysian mahseer, Tor tambroides Bleeker.

This study analysed morphology and histology of the developing mouth and digestive tract of the Malaysian mahseer larvae to assess the best weaning time to a compound diet for the fry on the basis of their morphological features. The mouth development was monitored using light and scanning electron microscopy; the development of the alimentary canal was followed histologically using light microscopy after haematoxylin-eosin staining. The larval mouth opened 1day after hatching (1 DAH); the histological structures of oesophagus were completed by 5 DAH. At 2 DAH, differentiation of enterocytes began, and at 7 DAH the supranuclear protein inclusion appeared in the posterior intestine. The hepatopancreas was structurally completed at 4-5 DAH, coinciding with the start of exogenous feeding and the evidence of lipid storage in the liver. It was concluded that Malaysian mahseer larvae should certainly be able to ingest, and possibly digest and absorb, a formulated diet of 287μm Ø from 7 DAH onward

Mitochondrial barcodes of dragonflies and damselflies originated from Taman Negara Endau Rompin, Johor, Malaysia

Dragonflies and damselflies (Odonates) are important biological indicators in freshwater ecosystems. However, identification among Odonates is often challenging due to their similar morphological features. Therefore, the incorporation of morphological identification by taxonomists and validation using mitochondrial barcodes such as cytochrome c oxidase subunit I (COI) can be a more reliable approach to enhance the accuracy in species identification. In this study, four COI barcodes for Malaysian dragonflies (Neurothemis fluctuans) and damselflies (Neurobasis chinensis, Aristocypha fenestrella and Sundacypha petiolata) were generated. Three of the generated barcodes (D2 COI, D4 COI and D5 COI) supported the species identified by taxonomists meanwhile D3 COI deduced that the damselfly species was misidentified due to the very similar morphology between the same genus of damselfly. All of the COI barcodes are now available in the GenBank with the accession numbers of MT266926.1 (D2 COI), MT266925.1 (D3 COI), MT269676.1 (D4 COI) and MT266924.1 (D5 COI)

Effects of bottom substratum on survival and growth of early juveniles of blue swimming crab, (Linnaeus, 1758) in captivity

Aim: Cannibalism remains a limiting factor during the nursery culture of crabs. This study was undertaken to improve the rearing techniques by investigating the impact of bottom substratum on crablet survival and growth. The knowledge gained from the research will be useful for the communal seed culture and development of crab farming, which are important factors regarding farmers' job stability in the future. Methodology: Blue swimming crab, Portunus pelagicus (first settled (C1 crabs); initial average weight and SD of 0.02 ± 0.01g) were cultured in glass aquarium (90 x 44 x 34 cm) and their survival and growth were assessed after 22 days of culture in four types of substratum such as control (none), sand, soil, or sand + soil. All treatments had 25 juvenile crabs, each of which was triplicated. Feeding was done twice a day (9 am and 5 pm) to apparent satiation. Results: Survival of early juvenile crabs cultured with sand was substantially higher at 65.33 ± 6.11% than those cultured with soil, sand + soil or control at 29.33 ± 10.07%, 28.00 ± 8.00%, and 21.33 ± 6.11%, respectively. Growth performance (such as final weight, weight gain and specific growth rate) of the early juvenile of P. pelagicus in all treatments were not significantly different (p>0.05). Interpretation: Overall, the best survival was achieved with sand substratum and can be recommended as a mean of reducing cannibalism during the early nursery rearing of blue swimming crab juveniles under captive culture conditions

A comparative study of proximate composition of Artemia urmiana enriched with different sources and levels of HUFA

The nutritional quality of commercially available Artemia strains is relatively poor in Eicosapentaenoic acid (EPA), Arachidonic acid (ARA) and especially Docosahexaenoic acid (DHA). Hence, it is essential and common practice to enrich this live prey with emulsions of special oils. One commercial ICES30/4 (Belgium), Linseed oil as a vegetable oil, Cod liver oil and Sturgeon ovary oil as two animal oils with EPA amounts in these oils were 6.29, 0.03, 11.39, 7.55 and the DHA amounts were 20.90, 0.00, 7.64, 2.76 respectively with three concentrations (100, 200 and 300ppm) during two enrichment periods (12 and 24h) were tested in order to improve the HUFA content, the DHAIEPA ratio and ARA content of Artemia urmiana nauplii. The results showed that Artemia enriched with different levels of vegetable oil and enrichment periods was poor in relation to either HUFA content and DHAIEPA ratio but the fish oils and emulsion resulted in HUFA incorporation. Sturgeon ovary oil caused the poorest DHAIEPA ratio enrichment (0.40 in 300ppm-24h) but the commercial emulsion (ICES30/4) was found as the best for DHA/EPA ratio enrichment (1.20 in 300ppm-24h). Cod liver oil (0.53 in 100ppm-24h) can be a good internal source substitute for improving the DHAIEPA ratio enrichment compared to ICES30/4 due to price and availability. As a result, HUFA content was increased with enrichment level 200ppm during 24h. Also, all oil sources improved lipid and protein percentages in A. urmiana nauplii

Effects of different diets on growth, survival and body composition of Rutilis frisii kutum larvae

The main objective of this study was to investigate the effect of different diets on Caspian kutum larval growth, survival and body composition, thus the Caspian kutum was examined in diets, Starved (S), Egg yolk (E), Artemia nauplii (A) and Artemia nauplii plus egg yolk (A+E). Totally four dietary treatments were tested in triplicate for 30 days. A significant growth difference between fry fed was observed in Artemia plus egg yolk (p<0.05). Final mean lengths and weights for each treatment (S, A, E, A+E), respectively were 7.0±0.07, 26±0.91, 23.5±0.91, 28.6±0.18 mm (Mean±SE, n = 12) and 4.9±0.08, 57±2.14, 51±2.18, 74±3.64 mg (Mean±SE, n = 12). The larvae accumulated increasing protein in Treatment A+E and lipid in treatment E (p<0.05). Also, the highest survival rate, 70.9±2.1%was in the treatment A+E and was significantly higher compared to 59.5±1.45% and 56.6±0.98%and in the other group (p<0.05). During culture period some other factors such as DGC (Daily Growth Coefficient), DWG (Daily Weight Gain), DLG (Daily Length Gain) and SGR (Specific Growth factor Rate) were measured. The obtained result showed that diet Artemia plus egg yolk is promising for use in Caspian kutum culture for in early stages of life cycle

Acute and sub-chronic toxicity of a trypsin-modulating oostatic factor (TMOF) on the growth, body composition and histopathology of red hybrid tilapia, Oreochromis sp. as a non-target organism

Trypsin-modulating oostatic factors (TMOF) have been shown to be an effective larvicide to mosquitos as a means of controlling their populations and spread of diseases, however there is limited information on its effects to fish, a non-target organism. Two experiments were performed to assess the acute and sub-chronic toxicity of a TMOF product to tilapia. For the acute toxicity test, treatments consisted of a control (0), 100, 500, 1000, 1500 and 2000 mg/L TMOF, which were triplicated with 10 fish/replicate according to the static renewal method. For the sub-chronic test, there were four triplicated treatments (50 fish/replicate) consisting of a control, TMOF at 60 mg/L, TMOF treated diets and a combination of these and the test was conducted for 35 days. After 35 days, growth performance, hepatosomatic index (HSI), vicersomatic index (VSI), whole-body proximate composition, and histopathology of the gills, liver and intestine were recorded. No LC50 values were obtained, even when using TMOF at saturated levels, within 96 hours. Meanwhile, after 35 days no significant differences in all of the measured parameters were detected among the treatments. Based on these findings, the TMOF product showed no acute or sub-chronic toxicity to tilapia and is safe to this non-target organism