Accumulation of acaricide resistance mechanisms in Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) populations from New Caledonia Island     

Chevillon C  Ducornez S  de Meeûs T  Koffi BB  Gaïa H  Delathière JM  Barré N 《Veterinary parasitology》2007,147(3-4):276-288

Rhipicephalus (Boophilus) microplus has been pesticide-controlled for several decades in the pacific island of New Caledonia. Since 1996, pesticide-control has been based on either deltamethrin (Butox) or amitraz (Taktic) in herds harbouring deltamethrin-resistant ticks. In this island, the first R. microplus deltamethrin- and amitraz-resistances were detected in 1992 and 2003, respectively. Using LPT bioassays, we have undertaken to update data regarding the geographical distribution and the physiological diversity likely to be involved in these resistances. We confirmed that after 17 years of intensive use of deltamethrin, several resistances of moderate levels (<30-fold) have evolved and/or diffused in any part of the island. We also evidenced that amitraz-resistant phenotypes have recently evolved in diverse western tick populations, although none has reached fixation in any tick population yet. According to synergists bioassays, the physiological changes involved in amitraz-resistance in New Caledonia would involve target modification and detoxifying P450 cytochrom oxydase(s). It may also involve detoxifying esterase(s) although this later point will need confirmation on samples bearing higher frequency of resistant phenotypes. Results are discussed with regard to the local evolutionary dynamics of resistance.  相似文献   

RhizoTubes as a new tool for high throughput imaging of plant root development and architecture: test,comparison with pot grown plants and validation     

Christian?Jeudy  Marielle?Adrian  Christophe?Baussard  Céline?Bernard  Eric?Bernaud  Virginie?Bourion  Hughes?Busset  Lloren??Cabrera-Bosquet  Frédéric?Cointault  Simeng?Han  Mickael?Lamboeuf  Delphine?Moreau  Barbara?Pivato  Marion?Prudent  Sophie?Trouvelot  Hoai?Nam?Truong  Vanessa?Vernoud  Anne-Sophie?Voisin  Daniel?Wipf  Christophe?SalonEmail author 《Plant methods》2016,12(1):31

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Influence of pig substitution on milk yield, litter weights, and milk composition of machine milked sows.     

A S Garst  S F Ball  B L Williams  C M Wood  J W Knight  H D Moll  C H Aardema  F C Gwazdauskas 《Journal of animal science》1999,77(7):1624-1630

This study was conducted to 1) determine milk yield of sows that were machine milked up to four times daily; 2) determine the effect of pig substitution on milk yield; 3) assess litter weight changes for sows that are milked; and 4) determine milk composition. Eight sows were milked four times daily to d 51 postpartum. Sows either maintained their own litter or had a week-old replacement litter to replace 25-d-old pigs. Individual gland milk yields were obtained on random days throughout lactation, and different diameter and weighted teat cups were rotated so that all glands received all combinations. Composite milk samples were analyzed for fat, protein, and somatic cells. Milk yields peaked at about 19 d postpartum and declined to 45 d postpartum in sows with their own litter, whereas milk yields peaked earlier and had a more dramatic decline after fostering of a younger litter. Litter weights were 17.1 +/- 1.0 kg at farrowing with 13.6 +/- .6 pigs born alive. Final litter weights were 34.4 +/- 11.7 kg for sows with replacement litters and 74.4 +/- 13.5 kg for sows with their own litters, and numbers of pigs weaned were 6.5 +/- 1.3 and 9.7 +/- 1.5, respectively. Milk fat was influenced by route of oxytocin administration (6.53 +/- .12 for i.v. vs 7.21 +/- .19% for i.m. administration; P < .05). Milk fat percentage was highest on d 2 and declined to 13 d postpartum. Milk protein was influenced by time of day of milking (lowest at the fourth milking, 5.57 +/- .11%) and followed a pattern similar to that for milk fat. Milk protein was affected in a linear manner by milk yield, with highest protein associated with lowest milk yields. Somatic cells in milk were influenced by litter replacement (P < .05) and oxytocin administration (P < .01). There was a linear increase in somatic cells from about 8 x 10(6) cells/mL milk at d 2 to more than 12 x 10(6) cells/mL milk at d 51 postpartum. These results show that pig replacement affects the amount of milk obtained. Moreover, milk composition changes throughout lactation. However, milk removal from sows has a severe impact on litter weight gains, and in systems where sow's milk is needed for commercial purposes, pig supplementation is necessary.  相似文献   

Sensory Analysis of Rainbow Trout,Oncorhynchus mykiss,Fed Enriched Black Soldier Fly Prepupae,Hermetia illucens     

Wendy M. Sealey  T. Gibson Gaylord  Frederic T. Barrows  Jeffery K. Tomberlin  Mark A. McGuire  Carolyn Ross  Sophie St‐Hilaire 《Journal of the World Aquaculture Society》2011,42(1):34-45

A growth trial and fillet sensory analysis were conducted to examine the effects of replacing dietary fish meal with black soldier fly (BSF) prepupae, Hermetia illucens, in rainbow trout, Oncorhynchus mykiss. A practical‐type trout diet was formulated to contain 45% protein; four test diets were developed by substituting 25 and 50% of the fish meal with normal (BSF) or fish offal‐enriched black soldier fly (EBSF) prepupae. Dietary fat was adjusted to approximately 20% lipid using fish oil and poultry fat. Diets were fed to three replicate tanks of fish per treatment (10 fish/tank) for 8 wk. After the trial, three fish per tank were sampled for determination of hepatosomatic index, intraperitoneal fat ratio and muscle ratio, and muscle proximate and fatty acid composition. Fish remaining after sampling were used for sensory evaluation. Growth of fish fed the EBSF diets was not significantly different from those fish fed the fish meal‐based control diet, while the growth of fish fed the BSF diets was significantly reduced as compared to the control diet. A group of 30 untrained panelists did not detect a significant difference in a blind comparison of fish fed the fish meal containing control diet as compared to fish fed the EBSF or BSF diets.  相似文献   

Ecoviability for ecosystem‐based fisheries management          下载免费PDF全文

Luc Doyen  Christophe Béné  Michel Bertignac  Fabian Blanchard  Abdoul Ahad Cissé  Catherine Dichmont  Sophie Gourguet  Olivier Guyader  Pierre‐Yves Hardy  Sarah Jennings  Lorne Richard Little  Claire Macher  David Jonathan Mills  Ahmed Noussair  Sean Pascoe  Jean‐Christophe Pereau  Nicolas Sanz  Anne‐Maree Schwarz  Tony Smith  Olivier Thébaud 《Fish and Fisheries》2017,18(6):1056-1072

Reconciling food security, economic development and biodiversity conservation is a key challenge, especially in the face of the demographic transition characterizing many countries in the world. Fisheries and marine ecosystems constitute a difficult application of this bio‐economic challenge. Many experts and scientists advocate an ecosystem approach to manage marine socio‐ecosystems for their sustainability and resilience. However, the ways by which to operationalize ecosystem‐based fisheries management (EBFM) remain poorly specified. We propose a specific methodological framework—viability modelling—to do so. We show how viability modelling can be applied using four contrasted case‐studies: two small‐scale fisheries in South America and Pacific and two larger‐scale fisheries in Europe and Australia. The four fisheries are analysed using the same modelling framework, structured around a set of common methods, indicators and scenarios. The calibrated models are dynamic, multispecies and multifleet and account for various sources of uncertainty. A multicriteria evaluation is used to assess the scenarios’ outcomes over a long time horizon with different constraints based on ecological, social and economic reference points. Results show to what extent the bio‐economic and ecosystem risks associated with the adoption of status quo strategies are relatively high and challenge the implementation of EBFM. In contrast, strategies called ecoviability or co‐viability strategies, that aim at satisfying the viability constraints, reduce significantly these ecological and economic risks and promote EBFM. The gains associated with those ecoviability strategies, however, decrease with the intensity of regulations imposed on these fisheries.  相似文献   

A comparison of the use of different swab materials for optimal diagnosis of amoebic gill disease (AGD) in Atlantic salmon (Salmo salar L.)     

Carolina Fernandez-Senac  Sophie Fridman  Jadwiga Sokolowska  Sean J. Monaghan  Teresa Garzon  Monica Betancor  Giuseppe Paladini  Alexandra Adams  James E. Bron 《Journal of fish diseases》2020,43(11):1463-1472

Routine gill swabbing is a non-destructive sampling method used for the downstream qPCR detection and quantitation of the pathogen Neoparamoeba perurans, a causative agent of amoebic gill disease (AGD). Three commercially available swabs were compared aiming their application for timelier AGD diagnosis (Calgiswab^® (calcium alginate fibre-tipped), Isohelix^® DNA buccal and cotton wool-tipped). Calcium alginate is soluble in most sodium salts, which potentially allows the total recovery of biological material, hence a better extraction of target organisms’ DNA. Thus, this study consisted of (a) an in vitro assessment involving spiking of the swabs with known amounts of amoebae and additional assessment of retrieval efficiency of amoebae from agar plates; (b) in vivo testing by swabbing of gill arches (second, third and fourth) of AGD-infected fish. Both in vitro and in vivo experiments identified an enhanced amoeba retrieval with Calgiswab® and Isohelix® swabs in comparison with cotton swabs. Additionally, the third and fourth gill arches presented significantly higher amoebic loads compared to the second gill arch. Results suggest that limiting routine gill swabbing to one or two arches, instead of all, could likely lead to reduced stress-related effects incurred by handling and sampling and a timelier diagnosis of AGD.  相似文献   

Methacarn preserves mucus integrity and improves visualization of amoebae in gills of Atlantic salmon (Salmo salar L.)     

Carolina Fernandez  Dario Mascolo  Sean J. Monaghan  Johanna L. Baily  Lynn Chalmers  Giuseppe Paladini  Alexandra Adams  James E. Bron  Sophie Fridman 《Journal of fish diseases》2019,42(6):883-894

Two aqueous fixation methods (modified Davidson's solution and modified Davidson's solution with 2% (w/v) Alcian blue) were compared against two non‐aqueous fixation methods (methacarn solution and methacarn solution with 2% (w/v) Alcian blue) along with the standard buffered formalin fixation method to (a) improve preservation of the mucous coat on Atlantic salmon, Salmo salar L., gills and (b) to examine the interaction between the amoebae and mucus on the gill during an infection with amoebic gill disease. Aqueous fixatives demonstrated excellent cytological preservation but failed to deliver the preservation of the mucus when compared to the non‐aqueous‐based fixatives; qualitative and semi‐quantitative analysis revealed a greater preservation of the gill mucus using the non‐aqueous methacarn solution. A combination of this fixation method and an Alcian blue/Periodic acid–Schiff staining was tested in gills of Atlantic salmon infected with amoebic gill disease; lectin labelling was also used to confirm the mucus preservation in the methacarn‐fixed tissue. Amoebae were observed closely associated with the mucus demonstrating that the techniques employed for preservation of the mucous coat can indeed avoid the loss of potential mucus‐embedded parasites, thus providing a better understanding of the relationship between the mucus and parasite.  相似文献   

Evaluating the use of garlic (Allium sativum) for the remedy of Cryptocaryon irritans in guppies (Poecilia reticulata)     

Ji Hyun Kim  Sophie Fridman  Hamutal Borochov‐Neori  Tamar Sinai  Dina Zilberg 《Aquaculture Research》2019,50(2):431-438

Garlic (Allium sativum) has been shown to possess antimicrobial properties against a range of disease‐causing agents, including fish parasites. Our study aimed to investigate the potential use of garlic as a treatment against Cryptocaryon irritans infection, using guppies (Poecilia reticulata) as the fish model. Garlic was freeze‐dried, powdered, and used as it is or as an aqueous extract. The content of allicin, its main active ingredient, was 1.25 mg/g in garlic powder and 0.82 mg/ml in the aqueous extract, as determined by HPLC analysis. Aqueous garlic extract fully immobilized C. irritans theronts and protomonts within 20 and 40 min, respectively, following exposure to 5 µl/ml. Treatment trials were performed, in which infected fish were fed with garlic powder‐supplemented feeds (5%, 10%, or 20% supplementation), bathed in garlic aqueous extract (250 or 500 µl/L) and subjected to a combined treatment which included both feeding and bathing. Results revealed that the tested treatments failed to cure the infection, though reduction in infection intensity on the caudal fin, but not on the gills, was evident following dietary supplementation with 20% of powdered garlic in one of the trials.  相似文献   

Instream mesohabitat biodiversity in three groundwater streams under base‐flow conditions     

P.J. Wood  P.D. Armitage  C.E. Cannan  G.E. Petts 《水产资源保护:海洋与淡水生态系统》1999,9(3):265-278

1. Concerns regarding the ecological functioning and biodiversity of groundwater‐dominated rivers have been highlighted in the wake of increased water resource pressures, channel management activities and natural drought. 2. The macroinvertebrate communities within three groundwater‐dominated streams in the UK, subject to different management strategies, were examined in relation to substratum mesohabitat diversity. 3. The mesohabitat structure was similar at all three sites examined but the number of taxa present at each site varied markedly. 4. Differences found at each site are related to (i) recent hydrological conditions (drought severity) and (ii) management activities, and are discussed with reference to the conservation and restoration of riverine systems. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   

Intestinal Contents Supernatant Viscosity of Rats Fed Oat-Based Muffins and Cereal Products     

Daniel D. Gallaher  Kimberly J. Wood  Cynthia M. Gallaher  Leonard F. Marquart  Alta M. Engstrom 《Cereal Chemistry》1999,76(1):21-24

The intestinal contents viscosities of oat-based breakfast cereals and muffins were examined. Male Sprague-Dawley rats were adapted for four days to a semipurified diet (AIN-76A). Following an overnight fast, the animals were meal-fed 5 g of either the AIN-76A diet (containing 5% cellulose), the AIN-76A diet containing 2% guar gum, whole-grain oat flour, one of five cereals (corn flakes, cooked oatmeal, uncooked oatmeal, cooked oat bran, or Cheerios), or one of two types of muffins (containing whole-grain oat flour or oatmeal). Two hours after presentation of the meal, the animals were killed, the small intestines removed, and the contents collected. The contents were centrifuged, and the viscosity values of the undiluted supernatants were determined. The supernatant viscosity from rats fed the AIN-76A diet was negligible (<5 mPa·sec), whereas that from rats fed guar gum was high (396 ± 117 mPa·sec). Of the cereals fed, corn flakes resulted in the lowest viscosity (<5 mPa·sec). However, all oat-based cereals resulted in high intestinal contents supernatant viscosity levels (cooked oatmeal 368 ± 128, uncooked oatmeal 307 ± 107, cooked oat bran 301 ± 85, Cheerios 199 ± 58, mPa·sec) with no statistically significant differences. The intestinal contents viscosity values for the whole-grain oat flour muffin and oatmeal muffin were 233 ± 52 and 111 ± 26 mPa·sec, respectively, a statistically significant difference (P < 0.05). This suggests that the form of the oat within a food may influence the degree of viscosity produced within the small intestine after that food is consumed.  相似文献