Dietary lipid requirement of whiteleg shrimp Litopenaeus vannamei juveniles cultured in biofloc system     

Ali Hamidoghli  Seonghun Won  Frolan A. Aya  Hyeonho Yun  Jinho Bae  In‐Kwon Jang  Sungchul C. Bai 《Aquaculture Nutrition》2020,26(3):603-612

An eight‐week feeding trial was conducted to evaluate the contribution of biofloc on dietary lipid requirement in whiteleg shrimp Litopenaeus vannamei. Five diets with graded levels of dietary lipid (45, 60, 90, 120 and 150 g/kg) were fed to juvenile shrimp. Final weight, weight gain and specific growth rate of shrimp fed diets with 60, 90 and 120 g/kg lipid levels were significantly higher than those of shrimp fed diets with lipid levels 45 and 150 g/kg (p < .05). Feed efficiency and protein efficiency ratio of shrimp fed 60, 90 and 120 g/kg were higher than those fed 150 g/kg diet. Plasma total cholesterol and triglyceride levels were lower in shrimp fed 45 g/kg compared with those fed the 90 g/kg (p < .05). Also, lysozyme activity for 90 g/kg group was higher than the 15 g/kg group. Hepatopancreas lipase and amylase activities of shrimp fed 90 and 120 g/kg diets were significantly higher than those of shrimp fed 45 and 150 g/kg diets. Broken‐line regression analysis for weight gain indicated that the dietary lipid requirement of whiteleg shrimp juveniles reared in a biofloc system was estimated to be higher than 56 g/kg but <60 g/kg.  相似文献   

Effects of two dietary probiotics (Bacillus subtilis or licheniformis) with two prebiotics (mannan or fructo oligosaccharide) in Japanese eel,Anguilla japonica     

Youngjin Park  Haham Kim  Seonghun Won  Ali Hamidoghli  Md Tawheed Hasan  In‐Soo Kong  Sungchul C. Bai 《Aquaculture Nutrition》2020,26(2):316-327

A 12‐week feeding trial was conducted to investigate the effects of two dietary probiotics; Bacillus subtilis KCTC 2217 or Bacillus licheniformis KCCM 11775 with two prebiotics; mannan oligosaccharide (MOS) or fructooligosaccharide (FOS) in Japanese eel. Fish averaging 12.8 ± 0.47 g (mean ± SD) were randomly distributed into five treatments with triplicate tanks. A basal control diet (CON) and four synbiotic diets supplementing B. subtilis + MOS (BSM), B. subtilis + FOS (BSF), B. licheniformis + MOS (BLM), and B. licheniformis + FOS (BLF). Weight gain and specific growth rate of fish fed all synbiotic diets were higher than those of fish fed CON. Immune‐related gene expression of heat shock protein 70 and immunoglobulin M of fish fed BSF and BLM were significantly higher than those of fish fed CON. Fish fed BSF and BLM had significantly higher intestinal villi length than those of fish fed BLF and CON (p < .05). Disease resistance against Aeromonas hydrophila of fish fed all synbiotic diets were significantly higher than those of fish fed CON (p < .05). Therefore, these results indicated that dietary B. subtilis with FOS (BSF) and B. licheniformis with MOS (BLM) could have beneficial effects on intestinal morphology, and immune‐related gene expression in Japanese eel.  相似文献   

Genetic variation in resistance of the tiger pufferfish Takifugu rubripes to a host-specific monogenean parasite Heterobothrium okamotoi     

Kim  Dong In  Hosoya  Sho  Mizuno  Naoki  Ito  Kotaro  Ieda  Risa  Kikuchi  Kiyoshi 《Fisheries Science》2019,85(6):1019-1025

Fisheries Science - The tiger pufferfish Takifugu rubripes is one of the most valuable aquaculture species in Japan. In this study, we investigated the genetic variation in resistance to...  相似文献   

Characterization of gonadotropic cells during continuous and seasonal spermatogenesis of two freshwater fish species: a histochemical and immunohistochemical study     

Rafael Henrique Nóbrega  Lázaro Wender Oliveira de Jesus  Renato Massaaki Honji  Maria Inês Borella 《Fish physiology and biochemistry》2017,43(1):51-63

This work describes gonadotropic (GtH) cells and their morphological and immunohistochemical changes during the spermatogenic cycle of Serrasalmus maculatus (continuous spermatogenesis) and Pimelodus maculatus (seasonal spermatogenesis). GtH cells, widely distributed in the proximal pars distalis of the adenohypophysis, were characterized as round-shaped cells with eccentric nucleus, and cytoplasm with basophilic secretory granules and a variable number of vacuoles for both species. Immunohistochemistry against β-follicle-stimulating hormone (Fsh) and β-luteinizing hormone (Lh) in adjacent sections showed two separated GtH-producing cell populations, and a third population where both GtHs are expressed in the same cell for both species. In the seasonal spermatogenesis of P. maculatus, GtH cells seemed to be more abundant during developing and spawning capable phases. In contrast, no cyclic changes were detected in the continuous spermatogenesis of S. maculatus, except for the strong immunoreaction for Fsh and Lh in males with intense spermiogenesis. We conclude that changes reported here might reflect the type of spermatogenic cycle (seasonal or continuous) which are under different regulatory mechanisms (environmental and internal cues) controlling the reproduction in these species.  相似文献   

Vegetated ridge and sandbag may not reduce soil erosion and loss of carbon and nutrients from upland fields     

Se-In Park  Hye In Yang  Hyun-Jin Park  Bo-Seong Seo  Dong-Hwan Lee  Young-Jae Jeong 《Soil Science and Plant Nutrition》2020,66(1):195-205

ABSTRACT

Though construction of vegetated ridge (VR) and placement of sandbag (SB) across the slope of upland fields are believed to be effective in reducing soil erosion and nutrient loss, relevant data are lacking to confirm such expectations. In this study, the effects of VR and SB on loss of soils, carbon (C), nitrogen (N), and phosphorus (P) (CNP) were investigated through both artificial (in dry season) and natural (in rainy season) runoff experiments on upland fields cultivated with maize (Zea mays L. var. ceratina). Contrary to expectations, both VR and SB were not effective in reducing the loss of soils and CNP. For VR, accelerated convergent flow caused by ridge failure, which occurred when part of the ridges collapsed because the amount of water collected in the furrows exceeded the water storage capacity of the ridges, led to excessive loss of soils and CNP. For SB, the loss of soils and CNP could be ascribed to the malfunction of SB; i.e., soil and CNP were lost by seepage through the gaps between SBs and between SB and soil surface. Maize growth and yield were not affected by VR and SB, coinciding with the lack of beneficial effects of VR and SB on soil and nutrient loss. As VR and SB are easy to be implemented and cost-effective, however, further study is necessary to correct the flaws of VR and SB found in this study.  相似文献   

Determination of the fluoroquinolone enrofloxacin in edible chicken muscle by supercritical fluid extraction and liquid chromatography with fluorescence detection   总被引：1，自引：0，他引：1  

Shim JH  Shen JY  Kim MR  Lee CJ  Kim IS 《Journal of agricultural and food chemistry》2003,51(26):7528-7532

A supercritical fluid extraction (SFE) method for the extraction of enrofloxacin from a chicken breast muscle was examined. A liquid chromatograph, equipped with a fluorescence detector, was used for the detection of enrofloxacin. Optimal extraction parameters, such as extraction time, supercritical fluid volume, modifier concentration, pressure, and temperature, were determined by examining SFE recoveries from control muscle samples spiked with enrofloxacin at different levels. In all of the experiments, high recovery values were observed, ranging from 101 to 104%. The extraction of enrofloxacin from real muscle samples was examined in chickens that were treated orally with enrofloxacin. Extraction was carried out by the SFE method after each oral treatment and under optimal extraction conditions at set intervals over time. The SFE, combined with liquid chromatographic analysis, showed that the concentration of enrofloxacin in the chicken muscles decreased continuously with time, giving a negligible concentration 72 h after the treatment. These results suggest that SFE is a useful approach for the extraction of enrofloxacin from chicken breast muscles.  相似文献   

Toxicity assessment of two IGR insecticides on eggs and larvae of the ladybird Eriopis connexa     

Fogel Marilina Noelia  Scorsetti Ana Clara  Minardi Graciela  Schneider Marcela Inés 《Pest management science》2023,79(4):1316-1323

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