Lumpy catfish, cause unknown. Pollution?

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Begin forwarded message:

From: noreply>
Date: 8 November 2011 6:20:06 AWST
To: Undisclosed Recipients
Subject: Disease News Update

AquaticHealth.net Disease News Update >> Catfish tumor – USA [ProMed request for information]

Link to source content: http://www.hometownannapolis.com/news/TOP/2011/10/31-31/Cause-of-catfish-tumors-still-unknown.html.

Your input is important: Please verify and add any relevant commentary to this report. Also, is the information in the report summarised somewhere in the Wiki?

Report Content:

CATFISH TUMOR – USA: (MARYLAND) REQUEST FOR INFORMATION

*******************************************************

A ProMED-mail post

ProMED-mail is a program of the

International Society for Infectious Diseases

Date: Mon 31 Oct 2011

Source: Howntownannapolis.com, The Capital Gazette [edited]

Cause of catfish tumors still unknown

How to increase fertility in fish

Posted on by TheFishVet - Richmond's School of Fish

Aquaculture International: Journal of the European Aquaculture Society Volume 19, Number 6 (December 2011)

Ovaprim treatment promotes oocyte development and milt fertilization rate in diploid and triploid African catfish (Clarias gariepinus)

Authors: Ali Karami 1, Annie Christianus 1, Hadi Zokaeifar 1, Khairul Saad 1, Fahmi Imraan 1, Shahram Shakibazadeh 1, Hossien Negarestan 2, Simon Courtenay 3 Author Affiliations:

1: Department of Aquaculture, Faculty of Agriculture, University Putra Malaysia, 43400 Selangor, Malaysia
2: Department of Aquatic Ecology of Caspian Sea, Iranian Fisheries Research Organization (IFRO), Tehran, Iran
3: Fisheries and Oceans Canada at the Canadian Rivers Institute, Department of Biology, University of New Brunswick, Fredericton, NB, Canada

Source: Aquaculture International: Journal of the European Aquaculture Society, Volume 19, Number 6 (December 2011) Page Numbers: 1025 – 1034 Available Full Text:

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Abstract:

Abstract

Triploid fish are increasingly used in aquaculture because they are generally unable to reproduce successfully. Energy is channeled into somatic growth rather than gonadal development, and in the event of escape, the animals are unlikely to breed successfully among themselves or with wild conspecifics. This study tested the ability of recently matured triploid African catfish (Clarias gariepinus) to produce and fertilize eggs with and without ovaprim treatment. Triploid females did not show the increase in ovary size observed in diploid members of the same cohort between 8 and 9 months of age, or the coincident decrease in visceral fat deposits, and this was unaffected by up to 5 weekly i.m. injections of 0.5 ml kg-1 Ovaprim. However, we observed advanced vitellogenin (Vtg) sequestration in oocytes of triploid females, albeit to a lesser degree and with lesser cortical alveoli, compared to oocytes from diploid cohort members. Histological sections revealed a positive trend of oocyte development up to the third weekly ovaprim injection followed by a negative gonadal development in weeks four and five. Milt from triploid males injected 9–12 h earlier with 0.25 ml kg-1 ovaprim i.m. fertilized more diploid eggs than milt from untreated triploid males (30 vs. 20%), but none of the developing embryos of triploid paternity survived to hatch. In contrast, milt of diploid males fertilized 49% of eggs, and 20% of the developing embryos hatched successfully. These rates were improved in ovaprim-injected diploid males to 70% fertilization and 33% hatch. This study demonstrates potential of overcoming non-viability of eggs from triploid female African catfish, and enhancing the ability of triploid milt to fertilize eggs.

Citation: Ali Karami, Annie Christianus, Hadi Zokaeifar, Khairul Saad, Fahmi Imraan, Shahram Shakibazadeh, Hossien Negarestan, Simon Courtenay . Ovaprim treatment promotes oocyte development and milt fertilization rate in diploid and triploid African catfish (Clarias gariepinus). Aquaculture International: Journal of the European Aquaculture Society, Volume 19, Number 6 (December 2011), pp. 1025-1034,

How to grow super abs

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Aquaculture Volume 321, Number 3-4 (December 2011)

Organic acids as potential growth promoters in the South African abalone Haliotis midae

Authors: Neill Jurgens Goosen, Johann Ferdinand Görgens, Lourens Francois De Wet, Hafizah Chenia Author Affiliations:

no affiliations available

Source: Aquaculture, Volume 321, Number 3-4 (December 2011) Page Numbers: 245 – 251 Available Full Text:

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Abstract: The study investigated organic acids and organic acid salts as growth promoters in cultured South African abalone Haliotis midaewhen incorporated as feed additives in formulated feed. Two blends of organic acids (1% acetic acid+1% formic acid, and 1% benzoic acid+1% sorbic acid) and one of organic acid salts (1% sodium benzoate+1% potassium sorbate) were evaluated in South African abalone (23mm initial mean length), and tested against a negative control and positive control containing 30ppm avilamycin as antibiotic growth promoter (AGP). Experiments were performed at controlled water temperatures under optimal (Phase 1) and sub-optimal (Phase 2) temperatures. During Phase 1 the organic acid and organic acid salt blends significantly enhanced mass growth rate (both linear weight increase [AGRW] and specific growth rate [SGR]) compared to both controls. Linear length increase (AGRL) was significantly higher than the negative control. SGR was increased by 15.8%–17.9% relative to the negative control; AGRW and AGRL were between 12.9%–22.9% and 11.7%–13.5% higher, respectively. No significant growth enhancement was observed during Phase 2. Avilamycin had no effect on growth and none of the treatments had significant effects on feed conversion ratio (FCR), relative incidence cost (RIC, relative to negative control) or feed intake during either phase. The mode of growth enhancement could not be established; it could not be shown that the acid and salt treatments or the AGP had any effects on intestinal microflora, but possible energy effects of the acids were eliminated as potential mechanism; it is unclear what role gut acidification played in the enhanced growth performance.

Citation: Neill Jurgens Goosen, Johann Ferdinand Görgens, Lourens Francois De Wet, Hafizah Chenia . Organic acids as potential growth promoters in the South African abalone Haliotis midae. Aquaculture, Volume 321, Numbers 3-4 (December 2011), pp. 245-251,

Oral treatment against marine Ich

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Aquaculture
Volume 321, Number 3-4 (December 2011)
In vitro and in vivo efficacies of ionophores against Cryptocaryon irritans

Authors: T. Yoshinaga, H.J. Im, S. Nishida, K. Ogawa
Author Affiliations: no affiliations available

Source: Aquaculture, Volume 321, Number 3-4 (December 2011)
Page Numbers: 167 – 172
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Abstract: We assayed the effects of a variety of antiprotozoal compounds against trophonts of Cryptocaryon irritans, the causative agent of ‘white spot disease of marine fish’ in vitro using the double layered media that we developed previously for the culture of the parasite. In the assay, ionophores, particularly sodium salinomycin, showed apparent killing and growth-suppression effects against the parasite. As there was no mortality in Japanese flounder Paralychthys olivaceusthat were fed a diet containing sodium salinomycin (200ppm) for two weeks, we evaluated the efficacy of 200ppm sodium salinomycin against C. irritansin Japanese flounder. We fed Japanese flounders a medicated diet for 5d prior to and 3d after challenge with C. irritans.In the experimental group, the number of protomonts recovered from the fish and the size of tomonts that were transformed from the protomonts were significantly reduced, when compared to the control group. Furthermore, in a different experiment, the fish that were fed a diet medicated with sodium salinomycin survived longer than those fed an unmedicated diet after challenge. Sodium salinomycin can be a good candidate drug for chemotherapy and control of Cryptocaron irritansinfection.
Citation: T. Yoshinaga, H.J. Im, S. Nishida, K. Ogawa . In vitro and in vivo efficacies of ionophores against Cryptocaryon irritans. Aquaculture, Volume 321, Numbers 3-4 (December 2011), pp. 167-172,

How TB escapes the immune system…

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I wonder if there are parallels with fish tuberculosis…

The article below is from –

http://www.sciencedaily.com/releases/2011/10/111003180430.htm

Tuberculosis bacterium’s outer cell wall disarms the body’s defense to remain infectious
18 October 2011
The bacterium that causes tuberculosis has a unique molecule on its outer cell surface that blocks a key part of the body’s defense. New research suggests this represents a novel mechanism in the microbe’s evolving efforts to remain hidden from the human immune system. Researchers found that the TB bacterium has a molecule on its outer surface called lipomannan that can stop production of an important protein in the body’s immune cells that helps contain TB infection and maintain it in a latent state. This protein is called tumor necrosis factor (TNF). When TNF is not produced in sufficient quantities, the TB bacterium can grow unchecked and cause an uncontrolled active infection inside and outside of the lungs. “There are several unique components on the Mycobacterium tuberculosisouter cell wall that help it sneak into the lung relatively unnoticed,” said Larry Schlesinger, professor and chair of the Department of Microbial Infection and Immunity at Ohio State University and senior author of the study. “The more we can learn about how these cell wall structures influence the human immune response, the closer we can get to developing a more effective strategy to treat or even prevent an active tuberculosis infection.”Lipomannan resembles a tree branch sprinkled with smaller sugar molecules protruding from the outer cell wall of the bacterium. The findings show that lipomannan can block TNF production at the microRNA level. MicroRNAs are small segments of RNA that regulate — or fine-tune — a gene’s protein-building function. To date, microRNAs have been implicated most frequently in the development of cancer. Schlesinger said this research is among the first studies to show that pathogenic bacteria can influence microRNA activation in immune cells and is the first to explore how microRNAs regulate the macrophage inflammatory response to Mycobacterium tuberculosis. Macrophages are first-responder cells in the immune response. They eat TB bacteria at the point of infection in the lung and then normally activate molecules that make pieces of the bacteria visible to infection-fighting warriors, triggering an eventual T-cell response to come to the macrophages’ aid. The research is published this week in the online early edition of the Proceedings of the National Academy of Sciences.About 2 billion people worldwide are thought to be infected with TB bacteria. People who are infected can harbor the bacterium without symptoms for decades, but an estimated one in 10 will develop active disease characterized by a chronic cough and chest pain. Both active and latent infections are treated with a combination of antibiotics that patients take for at least six months, and such treatment is becoming less effective with more drug-resistant bacterial strains. Schlesinger and colleagues conducted the study comparing lipomannans from two types of bacteria — a virulent strain of Mycobacterium tuberculosis and a harmless strain called Mycobacterium smegmatis, which is often used as a control bacterium in TB research. Many of these same researchers, led by Schlesinger, had previously isolated the lipomannans from each type of bacterial cell’s surface and used powerful biochemical analyses to characterize the significance of the lipomannans’ structural differences. In a study published recently in the Journal of Biological Chemistry, the group reported on how the surface structures on virulent TB bacteria lowered the response of a specific T-cell that typically gets recruited to fight tuberculosis. In this newer study, the scientists compared how the structures affected the production of TNF in primary human macrophage culture experiments.

They first established that human macrophages respond differently to the two different types of bacteria lipomannans after 24 hours of exposure. Lipomannan from the virulent TB bacterium produced significantly less TNF than lipomannan from the M. smegmatis bacterium. Though the study showed that the harmless cells increase production of TNF through a well-known receptor pathway as expected, the virulent TB bacteria did not make use of that receptor pathway. This supported the concept that the pathogenic TB bacterium has figured out another way to block the TNF protein in its quest to keep the immune system guessing, said Schlesinger, also the director of Ohio State’s Center for Microbial Interface Biology. A single microRNA can affect the production of hundreds of proteins, and the process of identifying those relationships is ongoing. However, two microRNAs in this study were known to be relevant for their connections to genes and proteins already established as players in the immune response to TB infection: miR-125b and miR-155.

Biochemical and genetic experiments showed that macrophages stimulated with lipomannan from TB bacteria had enhanced expression of miR-125b, effectively inhibiting the production of TNF. In contrast, the lipomannan from the harmless bacteria had enhanced expression of miR-155, which regulates other compounds in a way that stimulates TNF production. Researchers’ experimental manipulation to lower the expression of miR-125b in macrophages increased production of TNF in response to the TB bacteria lipomannan, further confirming that this regulation of TNF occurred at the microRNA level, Schlesinger said. “This really speaks to the power of the tuberculosis bacterium to adapt to the human host,” he said. “It has had centuries to develop a sophisticated way to deal with its encounter with the human. Fortunately, genomic technology is allowing us to identify microRNAs more and more rapidly, which might allow us to catch up with the TB bacterium and figure out a way to outsmart it.”