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81.
Francisco J Magallón Barajas Rosalía Servín Villegas Guillermo Portillo Clark & Berenice López Moreno 《Aquaculture Research》2006,37(5):492-499
Transport of post‐larvae shrimp used in aquaculture is an important element of successful cultivation because of the potential for stress during stocking procedures. To find optimum transport conditions, several bioassays were performed in the laboratory to evaluate survival of whiteleg shrimp Litopenaeus vannamei 5–30‐day‐old postlarvae under conditions similar to those encountered during transport from the hatchery to nursery and shrimp ponds. Postlarvae were exposed for 4 h to different temperatures and pH levels ammonia concentrations. Survival was significantly reduced after a 4 h exposure to pH 9 and was inversely related to temperature with or without 7 mg L?1 of ammonia. The 15‐ and 20‐day‐old postlarvae had higher survival rates than other ages. The lowest survival occurred in alkali conditions (pH 9), with 7 mg L?1ammonia at 30 and 32°C. To assure optimal survival of postlarvae during transfer from the hatchery to the nursery and shrimp ponds, we recommend temperatures below 28°C, pH no higher than 8, no ammonia and post‐larval age at least 15 days. 相似文献
82.
Robert Manuel L. Juárez-Gómez Juan Chaires-Pacheco Mariana Peña-Ramírez Yuri J. 《New Forests》2020,51(2):335-347
New Forests - Spanish red cedar, Cedrela odorata L. (Meliaceae), is a valuable timber tree in tropical American forests. Existing demand for elite individuals endangers the conservation of... 相似文献
83.
Mattana Efisio Peguero Brígido Di Sacco Alice Agramonte Wilvin Encarnación Castillo Wilkin Rafael Jiménez Francisco Clase Teodoro Pritchard Hugh W. Gómez-Barreiro Pablo Castillo-Lorenzo Elena Terrero Encarnación Marianny Way Michael J. García Ricardo Ulian Tiziana 《New Forests》2020,51(4):705-721
New Forests - Native trees from the Caribbean were tested for seed desiccation responses, by adapting the “100-seed test” protocol. Ninety-seven seed lots of 91 species were collected... 相似文献
84.
85.
Dalila F. Canizales-Rodríguez Víctor M. Ocaño-Higuera Enrique Marquez-Rios Abril Z. Graciano-Verdugo Jose L. Cárdenas-López María S. Yepiz-Gómez 《Journal Of Aquatic Food Product Technology》2013,22(3):259-269
Postmortem changes in blue shrimp (Litopenaeus stylirostris) muscle were studied on the basis of biochemical, chemical, physical, and microbiological changes during an 18 day storage period at 0°C. Adenosine 5′-triphosphate (ATP) content, breakdown products, K-value, pH, trimethylamine nitrogen (TMA-N), total volatile basic nitrogen (TVB-N), water holding capacity (WHC), color, and texture (shear force) changes were examined. Also, total mesophilic and psychrophilic bacterial counts were measured. K-value increased linearly (r2 = 0.98) from an initial value of 1.37 ± 0.59 to 59.42 ± 6.05% at Day 18. Spoilage indicators TVB-N and TMA-N increased from 29.56 ± 1.33 and 0.69 ± 0.25 to 39.04 and 2.04 ± 0.59 mg of N/100 g at Day 18, respectively; meanwhile, the total viable counts of mesophilic and psychrophilic bacteria increased from 3.48 ± 0.44 and 2.61 ± 0.29 log CFU/g to 6.27 ± 0.21 and 7.14 ± 0.39 log CFU/g, respectively, which indicated spoilage at the end of the storage period. The pH, texture, WHC, and color were affected (p < 0.05) during the storage period. Overall, results indicate that blue shrimp muscle quality was maintained for 12 days of storage in ice. 相似文献
86.
J R López S Núñez B Magariños N Castro J I Navas R de la Herran A E Toranzo 《Journal of fish diseases》2009,32(7):603-610
The first isolation of Tenacibaculum maritimum from wedge sole, Dicologoglossa cuneata, is reported. The pathogen was recovered from ulcers of cultured fish, from three different outbreaks. The six isolates obtained were biochemically and serologically characterized and diagnosis was confirmed by polymerase chain reaction using specific primers and partial 16S rRNA gene sequencing. The isolates constituted a homogeneous phenotypic group; however, they belong to two of the different serotypes described within this species. A virulence evaluation of the isolates using Wedge sole fry was also performed. 相似文献
87.
M. Pérez-López P. Anglade M.P. Bec-Ferté L. Debrauwer E. Perdu J.P. Cravedi P. Rouimi 《Fish physiology and biochemistry》2000,22(1):21-32
Liver, kidney, gill and olfactory epithelium cytosolic fractions of rainbow trout (Oncorhynchus mykiss) were examined for glutathione S-transferase (GST) contents. Proteins retained on a glutathione (GSH)-affinity matrix were separated as monomers by reversed-phase HPLC and characterized by immunoblotting, mass spectrometry and partial amino acid sequence. For each organ concerned, a specific pattern of these proteins was determined and appeared similar for liver and kidney on one hand, and for gill and olfactory epithelium on the other hand. It was confirmed that the prominent hepatic GST is a class enzyme, also constitutively expressed as a major isoform in the four organs studied. Moreover, a class variant and two new class GST subunits were characterized in minor fractions. An unknown protein, which was found major in gills and olfactory epithelium, exhibited some characteristics of class GSTs. Occurrence of possible GSH-adduct formation observed on two distinct monomers in specific experimental conditions is discussed. These results and methods were used to investigate the effect of 3,3,4,4-tetrachlorobiphenyl (TCB), a polychlorinated biphenyl (PCB), on GST expression in trout liver. From HPLC-profiling, significant co-induction of the major class and the two minor class GST subunits was observed in trout after waterborne exposure to TCB which was followed by a slight increase in 1-chloro-2,4-dinitrobenzene (CDNB) activity. The present work allows qualitative evaluation of the specific detoxification potential of rainbow trout. The use of HPLC-profiling of GSTs as a possible tool for the biomonitoring of polluted aquatic environment is suggested. 相似文献
88.
Histological alterations in gills of shrimp Litopenaeus vannamei in low‐salinity waters under different stocking densities: Potential relationship with nitrogen compounds 下载免费PDF全文
Marcela G. Fregoso‐López María S. Morales‐Covarrubias Miguel A Franco‐Nava Javier Ramírez‐Rochín Juan F Fierro‐Sañudo Jesús T Ponce‐Palafox Federico Páez‐Osuna 《Aquaculture Research》2017,48(12):5854-5863
Two experimental modules with different stocking densities (M1 = 70 and M2 = 120 shrimp /m2) were examined weekly over a culture cycle in tanks with low‐salinity water (1.9 g/L) and zero water exchange. Results showed survival rates of 87.7 and 11.9% in M1 and M2, respectively. Water temperature, pH, dissolved oxygen, electrical conductivity and chlorophyll a were not significantly (p > .05) different between modules. In contrast, the concentrations of nitrogen compounds were significantly (p < .05) different between modules, except nitrite‐N (M2 were 2.31 ± 1.38 mg/L N‐TAN, 0.18 ± 0.49 mg/L N‐NO2? and 6.83 ± 6.52 mg/L N‐NO3?; in M1: 0.97 ± 0.73 mg/L N‐TAN, 0.05 ± 0.21 mg/L N‐NO2? and 0.63 ± 0.70 mg/L N‐NO3?). When waters of both modules reached higher levels of ammonia and nitrite, histological alterations were observed in gills. The histological alterations index (HAI) was higher in M2 (5‐112) than in M1 (2‐22). 相似文献
89.
P.H. Strobl-Mazzulla G.C. López L.A. Miranda G.M. Somoza 《Fish physiology and biochemistry》2003,28(1-4):51-52
The molecular cloning of a cDNA encoding the pejerrey brain cytochrome P450 aromatase (P450aromB) is described. This form shares higher identity to other brain aromatases than with their respective ovarian counterparts and the self ovarian aromatase. Tissue-specific expression of both aromatases was examined in pejerrey by RT-PCR. The immunocytochemical distribution of P450aromB was described. 相似文献
90.
Long‐term effects of improved pasture establishment (with high proportion of legumes) on soil organic‐C status and N availability in Mediterranean cork oak (Quercus suber L.) woodlands were assessed. Soils were sampled beneath scattered crowns and in open areas, considering two systems: unmanaged and managed woodlands where improved pastures were installed 26 and 32 years ago. Total and labile C and N pools were measured and C and N mineralization were determined over 24 weeks laboratory incubation. Soils under improved pastures showed higher organic‐C, total‐N and net N mineralization than those under unmanaged pasture, mainly when established beneath trees. Potentially mineralizable C, C mineralization rate and microbial C were not statistically different between the unmanaged and improved pasture sites, but were higher closer to the tree than in the open area (1.8, 1.2 and 1.2 times, respectively). The qCO2 was higher in improved pastures (1.7 times). Labile pool of C and N extracted with hot water increased under improved pasture (3.4 and 1.7 times, respectively). Results indicate that soil quality amelioration by improved pastures is stronger in the presence of oak trees. Management systems that favour oak tree maintenance and regeneration should be taken into account to reverse soil degradation. 相似文献