Effect of Dietary Supplementation of Acidic Calcium Sulfate (Vitoxal) on Growth,Survival, Immune Response and Gut Microbiota of the Pacific White Shrimp,Litopenaeus vannamei     

J. Davies Anuta  Alejandro Buentello  Susmita Patnaik  Addison L. Lawrence  Ahmed Mustafa  Michael E. Hume  Delbert M. Gatlin III  Maurice C. Kemp 《Journal of the World Aquaculture Society》2011,42(6):834-844

Dietary acidifiers have been recognized as beneficial in animal production including aquacultural production of fish where they confer such benefits as improved feed utilization, growth, and resistance to bacterial pathogens. If improvements in growth and immune responses by acidifier supplementation can be confirmed in shrimp, then mortalities due to diseases could be minimized, limiting the emergence of disease‐resistant bacterial pathogens as a potential result of antibiotic misuse. With this in mind, a 35‐d feeding trial was conducted to evaluate growth, enteric microbiota populations, and nonspecific immune responses of Litopenaeus vannamei fed diets containing the commercial acidifier Vitoxal, based on acidic calcium sulfate in an indoor temperature‐controlled, recirculating culture system without any natural productivity. Experimental diets were formulated to contain 0 (basal), 0.4, 1.2, 1.6, or 2.0% acidic calcium sulfate (ACS) by weight. Shrimp fed in excess, 15 times a day using automatic feeders. Weight gain and survival among treatments were excellent, but not significantly different (P > 0.05). Denaturing gradient gel electrophoresis analysis revealed that the enteric microbial community of shrimp fed the basal diet differed markedly from those fed the acidifier on the basis of 64.9% similarity coefficient. Shrimp fed the commercial acidifier at 1.2 and 2.0% responded significantly (P < 0.05) better to reduced stress and displayed enhanced immune responses including hemocyte phagocytic capacity, hemolymph protein concentration, hyaline cell counts, and hemolymph glucose, compared with shrimp fed the basal diet. These results point to an enhanced performance in terms of positive shifts in the composition of enteric microbial communities as well as improved immune performance, with no changes in growth or survival.  相似文献   

Pyrethroid resistance in the cotton bollworm,Helicoverpa armigera (Hübner), in West Africa     

Thibaud Martin  Germain O Ochou  Franois Hala‐N'Klo  Jean‐Michel Vassal  Maurice Vaissayre 《Pest management science》2000,56(6):549-554

The susceptibility of Helicoverpa armigera to pyrethroids has been investigated in West Africa by means of laboratory bioassays since 1985, the first year of widespread pyrethroid use. For some years, this survey has shown a tendency for the pest to become more tolerant to pyrethroids. During the 1996 growing season, farmers using calendar‐based spraying programmes reported control failures in various countries. The strong efficacy of cypermethrin on small larvae was confirmed in experimental plots, but the effect decreased quickly in successive instars. Bioassays performed on resistant strains revealed an increase in LD₅₀ that was related to different resistance mechanisms. Metabolic resistance (MFO) appears to be a possible primary mechanism of resistance to pyrethroids. Target modification (kdr) is involved to a small degree and esterases seem to appear only after additional selection pressure. © 2000 Society of Chemical Industry  相似文献   

Comparison of three enzyme-linked immunosorbent assays for serologic diagnosis of contagious agalactia in sheep.     

Michel Pépin  Philippe Dufour  Maurice Lambert  Michel Aubert  Aurèle Valognes  Thierry Rotis  Anne Van de Wiele  Dominique Bergonier 《Journal of veterinary diagnostic investigation》2003,15(3):281-285

Serologic diagnosis of ovine contagious agalactia (Mycoplasma agalactiae) with the enzyme-linked immunosorbent assay (ELISA) developed by Agence Fran?aise de Sécurité Sanitaire des Aliments (AFSSA) may produce a few false-positive (FP) and false-negative (FN) results. When the prevalence of disease is low, these erroneous results may generate problems for eradication schemes. To prevent this, 2 commercial ELISAs were compared with the AFSSA ELISA. Flocks of known status were selected and classified into 4 categories: true positive (TP), FP, true negative (TN), and FN; 20 sheep per flock were submitted for blood sampling. A flock was considered positive when at least 1 out of 20 sera was positive or 2 sera were doubtful. In the flock, the diagnostic sensitivity of the 3 kits was very good (100%), and the diagnostic specificity showed an improvement from 46% (AFSSA test) to 88% and 92% (commercial tests). Considering individual animals, very few positive ewes were detected within TN or FP flocks; the proportion of positive ewes varied greatly from one kit to another (48% to 82%) within TP flocks. The kinetics of antibody response in sheep experimentally infected with various field strains of M. agalactiae were quite similar with all 3 ELISAs. The agreement between the 3 tests, assessed using the kappa value, varied from moderate to good (respective values of 0.56, 0.61, and 0.86). The 2 commercial ELISAs showed better performances, probably because of a superior analytical sensitivity, and are a good alternative for the serodiagnosis of contagious agalactia in sheep.  相似文献   

Attempted infection of Chad goats by bovine infections rhinotracheitis virus. Serological survey in West Chad     

Y Maurice  A Provost 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1970,23(4):419-423

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The Blood Sedimentation Test in the Diagnosis of Equine Infectious Anaemia     

Maurice Panisset 《Canadian journal of veterinary research》1938,2(1):3-12

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Root induction in Pinus ayacahuite by co-culture with Agrobacterium tumefaciens strains     

Saborio F  Moloney MM  Tung P  Thorpe TA 《Tree physiology》1999,19(6):383-389

Transformation of in-vitro-derived shoots of Pinus ayacahuite Ehrenb. was achieved by co-culture with an oncogenic strain (A281 x 200) of Agrobacterium tumefaciens. During co-culture rooting also occurred; however, this rooting was not induced by genetic transformation of host cells, because a "disarmed" strain of A. tumefaciens (EHA101) also induced rooting. Furthermore, direct contact between shoots and bacterial cells was not required. Rooting occurred in agar-solidified medium and in a soilless substrate (9:1 vermiculite:peat mix). We conclude that A. tumefaciens strains induced rooting in P. ayacahuite through a change in the rhizosphere, probably by producing some root-inducing compound(s), and not through transformation of host cells.  相似文献   

Resveratrol inhibits the activity of equine neutrophil myeloperoxidase by a direct interaction with the enzyme   总被引：2，自引：0，他引：2  

Kohnen S  Franck T  Van Antwerpen P  Boudjeltia KZ  Mouithys-Mickalad A  Deby C  Moguilevsky N  Deby-Dupont G  Lamy M  Serteyn D 《Journal of agricultural and food chemistry》2007,55(20):8080-8087

Resveratrol is a polyphenolic antioxidant present in beverage and food known for its multiple protective effects. We report the inhibitory effects of resveratrol on equine myeloperoxidase (MPO), a hemic peroxidase present in the granules of the neutrophils involved in the inflammatory response. Resveratrol inhibited the production of reactive oxygen species (ROS) by stimulated equine neutrophils by acting as a direct scavenger of the ROS released by the cells but did not modify the degranulation of the stimulated neutrophils as the amounts of released MPO were unchanged. Resveratrol strongly inhibited the chlorination, oxidation, and nitration activities of MPO in a dose-dependent manner. By an original technique of specific immunological extraction followed by enzymatic detection (SIEFED), we demonstrated that resveratrol inhibited the peroxidasic activity of the MPO measured by a direct interaction such as the fixation of resveratrol on the enzyme. The observation of a decrease of the accumulation of compound II suggested that resveratrol acts as an electron donor for MPO reduction.  相似文献   

Effect of the spray application technique on the deposition of entomopathogenic nematodes in vegetables     

Brusselman E  Beck B  Pollet S  Temmerman F  Spanoghe P  Moens M  Nuyttens D 《Pest management science》2012,68(3):444-453

BACKGROUND: The present study compared entomopathogenic nematode delivery at the base of savoy cabbage and cauliflower, at the lower side of savoy cabbage and cauliflower leaves and in leek stems and the ground deposition using a five‐nozzle spray boom equipped with an ISO 08 flat fan, an air induction flat fan and Twinjet spray nozzles. Additionally, an air support system and a row application system were evaluated. RESULTS: Approximately 40% of the applied nematodes did not reach the foot of the cabbage plants. The use of an air support system or a row application system improved nematode deposition at the savoy cabbage base. Relative nematode deposition on the lower side of savoy cabbage leaves was 27.20%, while only 2.64% of the applied nematodes reached the lower side of cauliflower leaves. After spraying leek with a standard boom, a low relative nematode deposition (26.64%) was measured in the leek stem. Nozzle type affected the distribution of nematodes in droplet spots. CONCLUSION: Nozzle type has a minor effect on the number of entomopathogenic nematodes delivered on difficult‐to‐reach targets. The use of modified spray application techniques directing the spray to the target site are necessary to increase the chances of contact of entomopathogenic nematodes with their target. Copyright © 2011 Society of Chemical Industry  相似文献   

Spatial and stochastic simulation to evaluate the impact of events and control measures on the 1997-1998 classical swine fever epidemic in The Netherlands. I. Description of simulation model     

Jalvingh AW  Nielen M  Maurice H  Stegeman AJ  Elbers AR  Dijkhuizen AA 《Preventive veterinary medicine》1999,42(3-4):271-295

The simulation model InterCSF was developed to simulate the Dutch Classical Swine Fever (CSF) epidemic of 1997–98 as closely as possible. InterCSF is a spatial, temporal and stochastic simulation model. The outcomes of the various replications give an estimate of the variation in size and duration of possible CSF-epidemics. InterCSF simulates disease spread from an infected farm to other farms through three contact types (animals, vehicles, persons) and through local spread up to a specified distance. The main disease-control mechanisms that influence the disease spread in InterCSF are diagnosis of the infected farms, depopulation of infected farms, movement-control areas, tracing, and pre-emptive slaughter. InterCSF was developed using InterSpread as the basis. InterSpread was developed for foot-and-mouth disease (FMD). This paper describes the process of modifying InterSpread into InterCSF. This involved changing the assumptions and mechanisms for disease spread from FMD to CSF. In addition, CSF-specific control measures based on the standard European Union (EU) regulations were included, as well as additional control measures that were applied during the Dutch epidemic. To adapt InterCSF as closely as possible to the Dutch 1997/98 epidemic, data from the real epidemic were analysed. Both disease spread and disease-control parameters were thus specifically based on the real epidemic. In general, InterSpread turned out to be a flexible tool that could be adapted to simulate another disease with relative ease. The most difficult were the modifications necessary to mimic the real epidemic as closely as possible. The model was well able to simulate an epidemic with a similar pattern over time for number of detected farms as the real outbreak; but the absolute numbers were (despite many relevant modifications) not exactly the same — but were within an acceptable range. Furthermore, the development of InterCSF provided the researchers with a better insight into the existing knowledge gaps. In part II (see the final paper in this issue), InterCSF was used to compare various control strategies as applied to this epidemic.  相似文献   

Intermittent claudication in an Afghan hound due to aortic arteriosclerosis     

Zandvliet MM  Stokhof AA  Boroffka S  van den Ingh TS 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(2):259-261

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