Effects of ascorbic acid enrichment by immersion of rainbow trout (Oncorhynchus mykiss, Walbaum 1792) eggs and embryos     

Bahram Falahatkar  Konrad Dabrowski  Murat Arslan  & Jacques Rinchard 《Aquaculture Research》2006,37(8):834-841

This study was conducted to examine the effects of different forms and concentrations of ascorbic acid (vitamin C), and different enrichment times (24 and 48 h post ovulation) on egg, embryo and alevin ascorbate concentrations and survival of rainbow trout (enrichment was at the ova stage). In experiments 1 and 2, fertilized eggs were immersed in water containing ascorbate at 0 (control), 100, 1000 mg L^?1 l ‐ascorbic acid (AA) and 2000 mg L^?1 l ‐ascorbyl monophosphate (AP). In experiment 3, 0 (control), 500 and 1000 mg L^?1 AA neutralized (N) with NaOH, 1000 mg L^?1 AA non‐neutralized (NN), 1000 and 2000 mg L^?1 AP immersions were used. The mean total ascorbic acid (TAA) and dehydroascorbic acid (DHA) concentrations were measured before fertilization, at 3 and 24 h after fertilization, at the eyed stage, and in hatched alevins. We observed significant differences in TAA concentration at different immersion levels at 3 and 24 h after fertilization. Survival decreased significantly depending on the level of vitamin C, pH of the solutions and immersion time. We suggest that when broodstock rainbow trout do not have enough vitamin C in their ovaries, immersion of eggs in 1000 mg L^?1 of neutralized AA may be useful.  相似文献   

A PROPOSED RADIOGRAPHIC CLASSIFICATION SCHEME FOR CONGENITAL THORACIC VERTEBRAL MALFORMATIONS IN BRACHYCEPHALIC “SCREW‐TAILED” DOG BREEDS     

Rodrigo Gutierrez‐Quintana  Julien Guevar  Catherine Stalin  Kiterie Faller  Carmen Yeamans  Jacques Penderis 《Veterinary radiology & ultrasound》2014,55(6):585-591

Congenital vertebral malformations are common in brachycephalic “screw‐tailed” dog breeds such as French bulldogs, English bulldogs, Boston terriers, and pugs. The aim of this retrospective study was to determine whether a radiographic classification scheme developed for use in humans would be feasible for use in these dog breeds. Inclusion criteria were hospital admission between September 2009 and April 2013, neurologic examination findings available, diagnostic quality lateral and ventro‐dorsal digital radiographs of the thoracic vertebral column, and at least one congenital vertebral malformation. Radiographs were retrieved and interpreted by two observers who were unaware of neurologic status. Vertebral malformations were classified based on a classification scheme modified from a previous human study and a consensus of both observers. Twenty‐eight dogs met inclusion criteria (12 with neurologic deficits, 16 with no neurologic deficits). Congenital vertebral malformations affected 85/362 (23.5%) of thoracic vertebrae. Vertebral body formation defects were the most common (butterfly vertebrae 6.6%, ventral wedge‐shaped vertebrae 5.5%, dorsal hemivertebrae 0.8%, and dorso‐lateral hemivertebrae 0.5%). No lateral hemivertebrae or lateral wedge‐shaped vertebrae were identified. The T7 vertebra was the most commonly affected (11/28 dogs), followed by T8 (8/28 dogs) and T12 (8/28 dogs). The number and type of vertebral malformations differed between groups (P = 0.01). Based on MRI, dorsal, and dorso‐lateral hemivertebrae were the cause of spinal cord compression in 5/12 (41.6%) of dogs with neurologic deficits. Findings indicated that a modified human radiographic classification system of vertebral malformations is feasible for use in future studies of brachycephalic “screw‐tailed” dogs.  相似文献   

Effects of dietary cottonseed meal protein level on growth, gonad development and plasma sex steroid hormones of tropical fish tilapia Oreochromis sp     

Jacques Rinchard  Godfrey Mbahinzireki  Konrad Dabrowski  Kyeong-Jun Lee  Mary-Ann Garcia-Abiado  Joseph Ottobre 《Aquaculture International》2002,10(1):11-28

Five experimental diets containing increasing proportions of cottonseedmeal (CSM) protein (0, 25, 50, 75 and 100%; diets 1 to 5, respectively) toreplace fish meal (FM) protein were formulated for intensive culture of tilapiaOreochromis sp. Each diet was fed to three replicategroupsof fish (mean weight ± SE = 11.3 ± 3.9 g) in30L aquaria connected as a closed recirculating-water system andmaintained at 27 ± 1 °C. Fish were fed three times adayby hand at a rate of 3% of body weight during four weeks, after which thefeeding rate was gradually decreased to reach 1.5% at 16 weeks. Thesubstitutionof 75 and 100% of FM proteins by CSM proteins resulted in significantly lowerbody weights in both sexes. In both sexes, gonadosomatic indexes and plasmaconcentrations of sex steroids (testosterone, 11-ketotestoterone,estradiol-17 and 17,20-dihydroxy-4-pregnen-3-one) were notsignificantly different among dietary treatments. The concentration ofgossypol,an antifertility agent contained in CSM, was measured in reproductive tissues.The total gossypol concentration in the testis was consistently lower than thatmeasured in the ovaries of the same group. Moreover, in both sexes, theconcentration of the (+)isomer of gossypol was always higher than that of(–)isomer. The total gossypol concentrations in testes increasedsignificantly with the increase of CSM in the diet. The highest levels of the(+)isomer (7.64 ± 0.62 g g^–1)were found in the testes of fish fed diet 4, whereas the (–)isomerreached its highest values in the testes of fish fed diet 5. The highest levelsof both enantiomers of gossypol were found in the ovaries of fish fed diet 4(14.2 ± 2.7 and 5.6 ± 1.5 g g^–1for (+) and (–)isomers, respectively). In both sexes, thehistological analysis of the gonads did not reveal differences among the fishfed different levels of CSM. Although CSM at any levels did not affect thereproductive parameters examined in this study, it cannot be used to substitutemore than 50% of FM since at higher levels growth of tilapia was compromised.  相似文献   

Effect of habitat fragmentation on spawning migration of brown trout (Salmo trutta L.)   总被引：2，自引：0，他引：2  

C. Gosset  J. Rives  J. Labonne 《Ecology of Freshwater Fish》2006,15(3):247-254

Abstract –  Human-induced habitat alteration is one of the main causes of the decline of freshwater fish populations. The watershed of the River Bidasoa (Spain) is an example of heavily fragmented habitat. The local brown trout ( Salmo trutta L.) population is disturbed, with evidence of poor recruitment as well as low adult densities in the main stem. Forty male and female adult migratory trout were tagged with external or internal radio transmitters and released. Fixed stations with data loggers and mobile antennae were used with daily surveys to track fish movements during the migration and spawning period (3 months). Migration distances did not exceed 10 km, and half of the fish never entered a tributary in the study area. Fragmentation because of weirs on the main stem apparently prevented fish from reaching their spawning destination. Fish that entered the tributaries were first confronted with an accessibility problem because of low discharge. However, each fish chose one tributary, without making attempts to run up in other tributaries. Once in the tributary, fish were restrained in their upstream movements by dams. The study area appeared to be isolated from the vast upper part of the watershed. Within the study area, upper parts of tributaries also seemed strongly disconnected from the main stem. This study illustrates the negative impact of river fragmentation on S. trutta migration pattern. Population sustainability can be directly affected through the low availability of spawning grounds for migratory fish. Long-term effects of fragmentation may cause reproductive isolation within watersheds, which in the case of trout also means isolated phenotypic population units.  相似文献   

Top-spraying soybean meal-based diets with phytase improves protein and mineral digestibilities but not lysine utilization in rainbow trout, Oncorhynchus mykiss (Walbaum)     

Jouni Vielma  Kari Ruohonen  Jacques Gabaudan  Kurt Vogel 《Aquaculture Research》2004,35(10):955-964

Two digestibility trials and two growth trials were carried out to evaluate the influence of top‐sprayed phytase on apparent digestibility coefficients (ADCs) of protein and mineral and utilization in rainbow trout fed with soybean meal‐based diets. In Trial 1, a semi‐purified diet containing 50% soybean meal was supplemented with graded levels of phytase (0, 500, 1000, 2000 and 4000 U kg^?1 diet), and fed to triplicate groups of fish. In Trial 2, commercial‐type extruded feeds containing 36% soybean meal with either 0 or 2000 U phytase kg^?1 were fed to five replicate groups of fish. Phytase clearly decreased phytic acid content of feces from 35 to 5 mg and from 34 to 14 mg phytic acid per g faecal dry matter in Trials 1 and 2 respectively. Apparent digestibility coefficient of P improved from 23% to 83% in Trial 1 and from 35% to 54% in Trial 2 by phytase. Apparent protein increased by 1.2% and 3.2%‐units by phytase in Trials 1 and 2. Zinc digestibility was significantly increased in Trial 1, but not in Trial 2. Trials 3 and 4 were conducted to evaluate the influence of phytase on dietary P (Trial 3) and lysine (Trial 4) utilization. Three diets were prepared for each trial: P (Trial 3)‐ or lysine (Trial 4)‐deficient basal diets, basal diets with phytase supplementation (2000 U kg^?1) and P (Trial 3)‐ or lysine (Trial 4)‐fortified diets. Rainbow trout (initial weight 20 g) were fed for 10 weeks using four and six replicates for Trials 3 and 4 respectively. Phytase increased P utilization in Trial 3 as demonstrated by an increase in vertebra ash from 24.1% to 45.4%, and by an increase in weight gain from 243% to 459% of the initial weight. Phytase did not increase lysine utilization, since neither protein retention nor weight gain were enhanced by phytase. Supplemental lysine increased protein retention and weight gain to 43.1% and 514%, respectively, and also decreased whole‐body lipid contents significantly from 120 to 123 g kg^?1 in fish fed the basal diet and phytase‐supplemented diet to 106 g kg^?1 in fish fed with lysine‐fortified diet.  相似文献   

Treatment of Hydroponics Wastewater Using Constructed Wetlands in Winter Conditions   总被引：1，自引：0，他引：1  

Vincent Gagnon  Gabriel Maltais-Landry  Jaume Puigagut  Florent Chazarenc  Jacques Brisson 《Water, air, and soil pollution》2010,212(1-4):483-490

Hydroponics culture generates large amounts of wastewater that are highly concentrated in nitrate and phosphorus but contains almost no organic carbon. Constructed wetlands (CWs) have been proposed to treat this type of effluent, but little is known about the performance of these systems in treating hydroponic wastewater. In addition, obtaining satisfactory winter performances from CWs operated in cold climates remains a challenge, as biological pathways are often slowed down or inhibited. The main objective of this study was to assess the effect of plant species (Typha sp., Phragmites australis, and Phalaris arundinacea) and the addition of organic carbon on nutrient removal in winter. The experimental setup consisted of 16 subsurface flow CW mesocosms (1 m², HRT of 3 days) fed with 30 L?d¹ of synthetic hydroponics wastewater, with half of the mesocosms fed with an additional source of organic carbon (sucrose). Carbon addition had a significant impact on nitrate and phosphate removal, with removal means of 4.9 g m^-2?d^-1 of NO₃-N and 0.5 g m^-2 d^-1 of PO₄-P. Planted mesocosms were generally more efficient than unplanted controls. Furthermore, we found significant differences among plant treatments for NO₃-N (highest removal with P. arundinacea) and COD (highest removal with P. australis/Typha sp.). Overall, planted wetlands with added organic carbon represent the best combination to treat hydroponics wastewater during the winter.  相似文献   

Molecular characerization of the interaction between the fungal pathogen Cladosporium fulvum and tomato     

Guy Honée  Guido F. J. M. Van den Ackerveken  Henk W. J. Van den Broek  Ton J. Cozijnsen  Matthieu H. A. J. Joosten  Mirian Kooman-Gersmann  Jacques Vervoort  Ralph Vogelsang  Paul Vossen  Jos P. Wubben  Pierre J. G. M. De Wit 《Euphytica》1994,79(3):219-225

The fungus Cladosprium fulvum is a biotrophic leaf pathogen of tomato. The fungus develops in the intercellular space without forming specialized feeding structures and does not affect the leaf tissue. The outcome of the C. fulvum-tomato interaction can be described by the gene-for-gene model. Failure of infection is expressed by a hypersensitive response. Two fungal proteins, ECP1 and ECP2, have been isolated and their corresponding genes have been cloned. In a compatible interaction including many physiological races ECP1 and ECP2 are highly produced and a role in pathogenicity is suggestive. The ecp1 gene shows some homology with tumor necrosis factor receptors (TNFRs) while the ecp2 gene shows no homology with sequences known in data bases. However, disruption of one of the two genes showed no reduced pathogenicity of the fungus. Two race-specific elicitors, AVR4 and AVR9, have been isolated and their corresponding genes have been cloned. The avirulence genes Avr4 and Avr9 are only present in C. fulvum avirulent on Cf-4 and Cf-9 cultivars, respectively. The expression of these two genes is, like the expression of the ecp genes, highly induced when the fungus grows in planta. Disruption of the Avr9 gene in wild type avirulent races leads to virulence on tomato genotypes carrying the complementary resistance gene Cf-9. A single base-pair change in the avirulence gene Avr4 leads to virulence on tomato genotypes carrying the Cf-4 resistance gene. Isolation, characterization and possible function of ECP1, ECP2, AVR4, and AVR9 will be discussed.  相似文献   

Comparative efficiencies of isopropyl and tert-butyl alcohols for extracting zeins from maize endosperm     

Landry J  Delhaye S  Damerval C 《Journal of agricultural and food chemistry》2002,50(14):4131-4134

Protein of endosperm of maize grains originating from three wild-type inbreds and their opaque-2 versions were solubilized in diverse extracts (E) by the sequential use of 0.5 M NaCl, water (E(1,2)), alcohol plus a reducing agent (E(3)), and salt plus a reducing agent (E(4)). Zeins were isolated in extracts E(3) and E(4) obtained by using 55% (w/w) isopropyl alcohol (i-PrOH) + 0.2% dithiothreitol (DTT) followed by 0.5 M NaCl + 0.2% DTT buffered at pH 10 or 60% tert-butyl alcohol (t-BuOH) + 0.2% DTT followed by 0.5% sodium acetate + 0.2% DTT in 30% t-BuOH. For a given genotype the percentage of extracted zeins was independent of the nature of the alcohol. The latter had a slight effect on the respective magnitude of E(3) and E(4): E(3) increased at the expense of E(4) when t-BuOH was substituted to i-PrOH for their isolation. The percentage of the total endosperm nitrogen present in E(3) + E(4) was identical to that of fractions F(II) + F(III) + F(IV) isolated according to the classical Landry-Moureaux extraction procedure. SDS-PAGE analysis revealed the presence of all types of zeins (alpha, beta, gamma, and delta) in E(3) and F(III), residual zeins in E(4) isolated with t-BuOH, and streaking only in E(4) and F(IV) isolated with NaCl at pH 10. The data together with those of the literature were discussed with regard to the influence of procedure on the yield of zeins using alcoholic extraction.  相似文献   

Origin of French virgin olive oil registered designation of origins predicted by chemometric analysis of synchronous excitation-emission fluorescence spectra     

Dupuy N  Le Dréau Y  Ollivier D  Artaud J  Pinatel C  Kister J 《Journal of agricultural and food chemistry》2005,53(24):9361-9368

The authentication of virgin olive oil samples requires usually the use of sophisticated and very expensive analytical techniques, so there is a need for fast and inexpensive analytical techniques for use in a quality control methodology. Virgin olive oils present an intense fluorescence spectra. Synchronous excitation-emission fluorescence spectroscopy (SEEFS) was assessed for origin determination of virgin olive oil samples from five French registered designation of origins (RDOs) (Nyons, Vallée des Baux, Aix-en-Provence, Haute-Provence, and Nice). The spectra present bands between 600 and 700 nm in emission due to chlorophylls a and b and pheophytins a and b. The bands between 275 and 400 nm in emission were attributed to alpha-, beta-, and gamma-tocopherols and to phenolic compounds, which characterize the virgin olive oils compared to other edible oils. The chemometric treatment (PLS1) of synchronous excitation-emission fluorescence spectra allows one to determine the origin of the oils from five French RDOs (Baux, Aix, Haute-Provence, Nice, and Nyons). Results were quite satisfactory, despite the similarity between two denominations of origin (Baux and Aix) that are composed by some common cultivars (Aglandau and Salonenque). The interpretation of the regression coefficients shows that RDOs are correlated to chlorophylls, pheophytins, tocopherols, and phenols compounds, which are different for each origin. SEEFS is part of a global analytic methodology that associates spectroscopic and chromatographic techniques. This approach can be used for traceability and vindicates the RDOs.  相似文献   

Optimization of headspace solid-phase Microextraction (SPME) for the odor analysis of surface-ripened cheese     

Lecanu L  Ducruet V  Jouquand C  Gratadoux JJ  Feigenbaum A 《Journal of agricultural and food chemistry》2002,50(13):3810-3817

Fifty volatile compounds of surface smear-ripened cheese were detected and identified using headspace solid-phase microextraction (HS-SPME) and vacuum distillation coupled to gas chromatography-mass spectrometry. Changes in the headspace of aroma compounds were monitored over the whole packaging period (47 days) using the HS-SPME method. Initially, the concentration of methanethiol increased before reaching a plateau. This evolution could be linked to the growth of Brevibacterium linens. During the shelf life of cheese, levels of acetic acid and 3-methylbutanoic acid remained constant, whereas butane-2,3-dione, 3-hydroxybutan-2-one, and hydroxypropan-2-one levels gradually declined and acetone and 3-methylbutanol levels dropped sharply to a plateau. Changes in odor could be related to changes of the rind, which behaved as a barrier, strongly influencing the distribution of volatile compounds in the headspace. Using a gas chromatography-olfactometry technique without separation, it was shown that the SPME extract was representative of the cheese odor.  相似文献