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Effects of Organic Selenium (OS) on Survival, Physiological and Immunological Response of Snub-Nosed Dart (Trachinotus Blochii Lacepide, 1801) Fingerlings When Challenged with Bacterial Infection and Copper Exposure
Get PDFTwo trials were conducted to determine the effects of diet supplemented with organic selenium (OS, Selplex, Alltech, Kentucky USA) on survival, physiological, and immunological parameters of snub-nosed dart (Trachinotus blochii Lacepide, 1801) when challenged with Nocardia sp. bacteria or when exposed to toxic levels of environmental copper. The fish were fed two different diets containing 0% (D1,control diet) and 0.03% OS (D2) for 12 weeks before challenge. Cumulative mortality, phagocytic activity, and respiratory burst of head kidney leucocytes, and physiological parameters including moisture content and lipid accumulation in the liver, moisture content, and crude protein in the flesh were recorded. Results showed that the cumulative mortality of fish fed Se supplemented diet was lower than that of the fish fed the control diet when challenged with Nocardia sp. Survival rate was 100% in both treatment groups when exposed to copper only. Phagocytic activity and respiratory burst were higher in fish fed D2 (Se supplemented) compared to the D1 group when challenged with Nocardia sp. Phagocytic activity was higher in fish fed Se supplemented diet compared to the control group when exposed to environmental copper. No significant differences in the protein content, total lipid, and moisture in liver and flesh were recorded between the diet groups. Results indicated that supplementation of 0.3 g/Kg of OS (Sel-Plex) in the diet of snub-nosed dart is recommended to enhance fish survival and immunity when challenged with bacteria Nocardia sp. and environmental Cu toxicity exposure
Effects of Replacing Fish Meal with Soybean Meal or Fermented and Phytase-Treated Soybean Meal Respectively, on Growth Performance, Feed Utilization, and Apparent Digestibility in Juvenile Turbot (Scophthalmus maximus L.)
Get PDFThe objective of this study was to evaluate the effect of fish meal (FM) substitution with gradient soybean meal (SBM) or fermented and phytase-treated soybean meal (PHSBM) in the diets of turbot (Scophthalmus maximus). A 9 week feeding trial was conducted using juvenile turbots (Scophthalmus maxima) fed seven experimental diets. The seven isonitrogenous (approximately 50% crude protein) and isoenergetic (approximately 21.0 kJ/g diet of gross energy) diets were formulated to include FM protein substitution with corresponding amounts of protein from soybean meal and phytase-treated soybean meal sources. Results showed that survival rate and feed intake did not differ significantly between the FM diet and any plant protein incorporated diets. Compared with the FM diet, final body weight and SGR were significantly reduced by the SBM2, SBM3, and PHSBM3 diets. Except for the PHSBM1 diet, feed efficiency ratio in the other SBM or PHSBM incorporated diets was much lower than in the FM diet. Body ash content was not affected by gradient PHSBM incorporated diets compared with the FM diet, while SBM incorporated diets (SBM2 and SBM3) showed a higher ash content than the FM diet (P<0.05). Body crude protein was significantly reduced when fishmeal protein was replaced by soybean meal up to 60% (SBM3). There was no significant difference in the crude lipid and moisture contents among different treatments. Fish meal replaced by gradient PHSBM did not affect the apparent digestibility coefficients (ADC) of dry matter and crude protein, while the ADC of dry matter was markedly reduced in all the soybean meal incorporated diets compared with the FM diet. These results show that 30% fish meal protein could be replaced by soybean meal in the diet of turbot, while PHSBM could be substituted for up to 45% dietary fish meal
Timing of Puberty and Reproductive Performance in Wild-Reared and Hatchery-Reared Pacific Red Snapper Lutjanus peru
Get PDFA ten-year study (2005 to 2015) was conducted to examine the timing of puberty and reproductive performance in Pacific red snapper Lutjanus peru. Wild young juveniles reared in a 200 m3 lined-pond from 2005 were captured and spawned over the next three consecutive years, starting in 2009. The study continued in hatchery-reared red snappers from the 2010 progenies that spawned in 2014. In wild-reared and hatchery-reared red snapper, puberty occurred in both sexes at three years and nine months. In a pond, eight wild-reared females had on average 54 days of broadcast spawning, which corresponded to 0.276 M viable eggs per day. Each female had on average 1.838 million (M) viable eggs, and a relative fecundity of 0.555 M eggs/kg yielding 0.010 M eggs/kg per spawn. All wild-reared males (n = 22) had running sperm. In progeny hatchery-reared red snapper, nine females had vitellogenic oocytes, but only three reproduced. Ninety percent of hatchery-reared males (n=31) had running sperm. The ratio of 11-ketosterone to estradiol allowed identification or corroboration of sex. Results suggest L. peru synchronizes reproduction according to photoperiod and water temperature. This species (2.3+ kg, 52.0+ cm) is a potential candidate for sustainable aquaculture, including rearing, and reproduction in captivity
Effects of Dietary Lecithin, Nucleoside, and Krill Supplementation to a Fishmeal Based Diet on Growth and Feed Utilization of Sharpsnout Sea Bream (Diplodus Puntazzo)
Get PDFThe aim of this 96 day feeding trial was to investigate the effects of the addition of different combinations of dietary lecithin, nucleosides, and krill to a fishmeal-based diet on the growth, feed utilization, feed consumption, and body composition of sharpsnout sea bream (Diplodus puntazzo). Six hundred (600) fish (average weight 21.21 ± 0.06SD g) were divided into 8 groups (triplicate treatments) and fed eight isoenergetic fishmeal-based diets, (C-control, L-lecithin, N-nucleosides, K-krill, L+N-lecithin+nucleosides, N+K-nucleosides+krill, L+K-lecithin+krill, L+N+K-lecithin+nucleosides+krill). The effects of the dietary regimes were evaluated in terms of specific growth rate (SGR), feed conversion ratio (FCR), daily feed intake (DFI), and whole body chemical composition (moisture, crude ash, crude protein and crude lipid). At the end the trial the fish had tripled their initial weight. SGR, FCR and DFI were 1.17-1.24 %, 0.95-1.01, and 1.03-1.14% respectively. Although differences were observed between some groups, none of the tested feed additives improved SGR, FCR, and DFI, compared to the control diet. Analysis of whole body proximate composition showed that moisture, crude ash, crude protein, and crude lipid ranged 61.45-64.00%, 3.96-4.26%, 15.44-17.26% and 14.87-18.82% respectively. Crude lipid concentration was higher in whole body of fish fed the nucleoside supplemented diet compared to control, lecithin, and krill groups. No other effects of the dietary regime on the whole body composition of sharpshout sea bream were observed
Evaluation of Dietary Anti-nutritional Factors and Amino Acids Supplementation on Growth, Feed Efficiency Ratio, and Apparent Digestibility of Japanese Flounder (Paralichthys olivaceus) at Equal Feed Intake
Get PDFA 30-day feeding trial was conducted to evaluate the anti-nutritional factors in fish meal-based diets, and limiting amino acids in soybean meal-based diets on growth, feed efficiency ratio (FER), and nutrient apparent digestibility (AD) of Japanese flounder (Paralichthys olivaceus) at equal feed intake. Four isonitrogenous and isoenergetic diets were formulated: Diet 1 contained fish meal as the main dietary protein source; Diet 2 was based on Diet 1 and supplemented with anti-nutritional factors; Diet 3 contained both fish meal and soybean meal as main protein source; Diet 4 was based on Diet 3 and supplemented with crystalline amino acids. All diets were assigned to triplicate groups of 5 fish per aquarium. Results from Diet 1 showed that force-feeding was a possible method to rear Japanese flounder with high FER and 100% survival rate. In the first three periods (4 days/period), weight gain (WG) and FER of fish fed Diets 2, 3 & 4 were significantly lower (P<0.05) than in fish fed Diet 1. After 30 days of the feeding trial, WG and FER of fish fed Diets 3 & 4 were significantly lower than in fish fed Diet 1 (P<0.05). No significant difference in WG and FER was observed either between fish fed Diets 1 & 2, or between fish fed Diets 3 & 4. The AD of dry matter and crude lipid of fish fed Diets 3 & 4 were significantly lower than those of fish fed Diet 1 (P<0.05). Results indicated that supplementation of anti-nutritional factors in a fish meal-based diet, or supplementation of crystalline amino acids in a soybean meal-based diet did not significantly affect growth performance of Japanese flounder by force feeding
Effects of Time after Hormonal Stimulation on Milt Properties in Waigieu Seaperch Psammoperca waigiensis
Get PDFThe objective of the present study was to assess the effects of time after stimulation with domperidone (DOM), luteinizing hormone releasing hormone analog (LHRHa), and human chorionic gonadotropin (HCG), on features of spermiation including milt physical properties, sperm motility parameters, and sperm morphology, in Waigieu seaperch Psammoperca waigiensis. Male broodfish were injected with either 0.9% saline solution (control), or a single dose of DOM [20 mg/kg body weight (BW)], LHRHa (20, 50, or 80 μg/kg BW), or HCG (500, 1000, or 1500 IU/kg BW). Milt samples were collected before hormone induction (0 h) to assess original milt condition, and at 24 h, 48 h, and 72 h post injection (p.i.). Results showed that treatment with saline solution, DOM, or LHRHa did not significantly alter milt physical properties, sperm motility parameters, or sperm morphology. Treatment with HCG at a dose of 1000 IU/kg BW significantly increased milt volume, total sperm production, and sperm motility parameters, but decreased spermatocrit and sperm concentration at 48 h p.i. These parameters were significantly reduced at 72 h p.i. In conclusion, our results suggest that Waigieu seaperch milt should be collected 48 h after hormonal stimulation with a single dose of HCG (1000 IU/kg BW) to ensure high properties of milt such as milt volume, total sperm production, and sperm motility parameters
Effect of Partial Substitution of Fish Meal with Sunflower Meal on Feed Utilization, Intestinal Digestive Enzyme, Hematological Indexes, Intestinal, and Liver Morphology on Juvenile Turbot (Scophthal musmaximus L.)
Get PDFA 70-day feeding trial was conducted to evaluate effects of partial substitution of fish meal (FM) by sunflower meal (SFM) on juvenile turbot (Scophthal musmaximus L.). Five isonitrogenous and isoenergetic diets were formulated with 0%, 15%, 25%, 35%, and 45% replacement of FM protein with protein from SFM. Triplicate groups of juvenile turbot (30 fish per group), were hand-fed twice daily to apparent satiation. Final body weight (FBW), specific growth rate (SGR), and weight gain rate (WGR), were not significantly influenced by type of plant protein at the 15% level (P>0.05), while higher levels showed significant reduction of FBW, SGR, WGR. Feed efficiency ratio (FER) and feed intake (FI) were significantly influenced when FM protein was replaced up to 45% (P0.05). In the SFM diet groups, all superoxide dismutase (SOD) values were significantly higher than the control (P0.05) in microvilli height between diets; parenchyma structure of liver was severely damaged; smaller hepatocyte areas and areas with high levels of hepatocyte vacuolization and disorganization were present. All results indicated that SFM protein can partially replace FM protein in juvenile turbot diets without adverse effects
Aeromonas veronii, Associated with Skin Ulcerative Syndrome, Isolated from the Goldfish (Carassius auratus) in China
Get PDFAeromonas infections are the most common bacterial disease in cultured fish. In April 2013, an epizootic ulcerative syndrome occurred on a goldfish farm in Xuzhou, central China. A gram-negative bacterium was isolated from the ulcerative lesions and internal organs of infected dragon-eye goldfish (Carassius auratus), tentatively named strain CAV-134. The results showed that the isolate was identified as Aeromonas veronii by physiological and biochemical characteristics, furthermore it was confirmed by 16S rRNA, gyrB, mu, asl and aha1 genes sequencing analysis. The pathogenicity of the isolate was confirmed in crucian carp and produced an LD50 of 1.99×106 CFU/ml. Antimicrobial susceptibility pattern of strain CAV-134 showed it was susceptible to most antimicrobial agents tested but resistant to ampicillin, amoxicillin, carbenicillin, vancomycin, teicoplanin, lincomycin and clindamycin. This is the report on the pathogenic A. veronii isolated from the skin ulcerative syndrome of dragon-eye goldfish
