Detection of Pathogenic Leptospires in Water and Soil in Areas Endemic to Leptospirosis in Nicaragua.

In Nicaragua, there are ideal environmental conditions for leptospirosis. The objective of this investigation was to detect pathogenic and saprophytic leptospires in water and soil samples from leptospirosis-endemic areas in Nicaragua. Seventy-eight water and 42 soil samples were collected from houses and rivers close to confirmed human cases.

A cross-sectional epidemiological study of domestic animals related to human leptospirosis cases in Nicaragua.

Leptospirosis is one of the most extended zoonosis worldwide and humans become infected most commonly through contact with the urine of carrier animals, either directly or via contaminated water or soil. The aim in this study was to analyse the epidemiological behaviour of Leptospira spp., from domestic animals around the sites of human leptospirosis cases in Nicaragua, from 2007 through 2013.

Accumulation and depletion kinetics of erythromycin in rainbow trout (Oncorhynchus mykiss).

Erythromycin is an antimicrobial agent recommended for the control and treatment of diseases caused by gram-positive bacteria. Few studies, however, have determined the metabolic and pharmacokinetic aspects of this antimicrobial agent in fish. The aim of the present study, therefore, was to determine the accumulation and depletion time of erythromycin after administration of medicated feed containing 52 mg kg(-1) body weight day(-1) for 8 days in rainbow trout (Oncorhynchus mykiss).

Effect of Lactococcus lactis CLFP 100 and Leuconostoc mesenteroides CLFP 196 on Aeromonas salmonicida Infection in brown trout (Salmo trutta).

Aeromonas salmonicida is the etiological agent of furunculosis in salmonid fish. This pathogen is important from an epizootic perspective because fish surviving an outbreak can remain lifelong asymptomatic carriers, serving as reservoirs of infection. As a result, the early detection and the control of infection are essential to prevent the spread of new furunculosis outbreaks.

Quantitative analysis of bacterial adhesion to fish tissue.

Adhesion to host tissue represents a first crucial step in most bacterial infections. Both specific adhesion-ligand as well as hydrophobic interactions may be involved. The adhesion of Aeromonas salmonicida subsp.

A new real time PCR-based assay for diagnosing Renibacterium salmoninarum in rainbow trout (Oncorhynchus mykiss) and comparison with other techniques.

Bacterial Kidney Disease of salmonid is caused by a slow-growing gram-positive bacterium, Renibacterium salmoninarum. This bacterium lives both extra-cellular and intra-cellular in the host. Serological and molecular diagnostic methods to detect the bacterium major surface protein antigen p57 have been developed.

Enhancement of the immune response and protection induced by probiotic lactic acid bacteria against furunculosis in rainbow trout (Oncorhynchus mykiss).

We analysed the effect of probiotic strains on the cellular and humoral immune responses of rainbow trout (Oncorhynchus mykiss), and their capacity to prevent furunculosis during a challenge trial. Probiotic strains (Lactococcus lactis ssp. lactis CLFP 100, Leuconostoc mesenteroides CLFP 196, and Lactobacillus sakei CLFP 202) were administered orally to fish for 2 weeks at 10(6) CFU g(-1) of feed.

Protection of rainbow trout (Oncorhynchus mykiss) from lactococcosis by probiotic bacteria.

We analysed the effect of probiotic supplementation on the control of lactococcosis in rainbow trout. Probiotic strains Leuconostoc mesenteroides CLFP 196 and Lactobacillus plantarum CLFP 238 were administered orally to fish for 30 days at 10(7) CFU g(-1) feed. Thirty days after the start of the probiotic feeding, fish were challenged with Lactococcus garvieae.

Safety and efficacy of an inactivated vaccine against Lactococcus garvieae in rainbow trout (Oncorhynchus mykiss).

We studied the safety and efficacy of an inactivated vaccine (Ichtiovac-Lg) against Lactococcus garvieae in rainbow trout (Oncorhynchus mykiss). In an initial dose-response experiment to test safety, we injected 50 rainbow trout weighing 30-40 g with a double dose of vaccine (0.2 ml) intraperitoneally.

In vitro competitive adhesion and production of antagonistic compounds by lactic acid bacteria against fish pathogens.

The present study describes the screening of five lactic acid bacteria (LAB) for use as probiotics based on their competitive adhesion and production of antagonistic substances against some fish pathogens. A reduction of adhesion of all pathogenic strains tested was obtained with three of the LAB strains (Lactococcus lactis subsp. lactis CLFP100, Lactococcus lactis subsp.

Quantitative detection of Aeromonas salmonicida in fish tissue by real-time PCR using self-quenched, fluorogenic primers.

In this study a real-time PCR assay using self-quenched primers labelled with a single fluorophore for the detection of Aeromonas salmonicida was developed. Probe specificity was confirmed by amplification of 16 A. salmonicida strain templates and by the lack of a PCR product with 26 non-A.

Changes in intestinal microbiota and humoral immune response following probiotic administration in brown trout (Salmo trutta).

We studied the effect of several lactic acid bacteria (LAB) on the humoral response of brown trout (Salmo trutta). LAB groups (Lactococcus (Lc.) lactis ssp.

Sequencing of variable regions of the 16S rRNA gene for identification of lactic acid bacteria isolated from the intestinal microbiota of healthy salmonids.

The aim of this study was to identify lactic acid bacteria (LAB) using polymerase chain reaction (PCR) amplification of variable regions of the 16S rRNA gene. Thirteen LAB strains were isolated from the intestinal microbiota of healthy salmonids. A approximately 500-bp region of the highly conserved 16S rRNA gene was PCR-amplified and following this, a portion of the amplicon (272-bp) including the V1 and V2 variable regions was sequenced.

Immune modulation by probiotic strains: quantification of phagocytosis of Aeromonas salmonicida by leukocytes isolated from gut of rainbow trout (Oncorhynchus mykiss) using a radiolabelling assay.

A method is described for the rapid and sensitive assay of phagocytosis that utilizes radioactively labelled bacteria. With this method, we observed that phagocytosis of heat-inactivated Aeromonas salmonicida by leukocytes isolated from gut of rainbow trout fed with different viable probiotics (Lactococcus lactis subsp. lactis, Lactobacillus sakei, and Leuconostoc mesenteroides) was significantly higher (P<0.

Lactococcus garvieae in fish: a review.

Lactococcus garvieae is the etiological agent of Lactococcosis, an emergent disease which affects many fish species and causes important economic losses both in marine and freshwater aquaculture when water temperature increases over 16 degrees C in summer months. Normally, it causes a hyperacute and haemorrhagic septicemia. This paper presents a state of the art review of fish Lactococcosis including aspects such as pathogen characterization, pathogenesis, epidemiology, diagnosis and control measures of the disease in farmed fish.

The role of probiotics in aquaculture.

The increase of productivity in aquaculture has been accompanied by ecological impacts including emergence of a large variety of pathogens and bacterial resistance. These impacts are in part due to the indiscriminate use of chemotherapeutic agents as a result of management practices in production cycles. This review provides a summary of the use of probiotics for prevention of bacterial diseases in aquaculture, with a critical evaluation of results obtained to date.

Physiological and genetic characterisation of some new Aphanomyces strains isolated from freshwater crayfish.

Five Aphanomyces strains were isolated during suspected outbreaks of crayfish disease in Spain and Italy. Genetic and physiological evidence show that the strains isolated from the freshwater crayfish Procambarus clarkii and Pacifastacus leniusculus, do not fit into any previously identified group of Aphanomyces astaci and are not capable of killing crayfish following standardised experimental infection. RAPD-PCR and ITS sequencing analysis show a high degree of similarity between the new isolates, while they are clearly different from the A.