Cull and cull hard.
I am adding some cut and pastes from the zebra fish NG.
Nice and scientific for ya
;-)
Read and they will explain exactly what your dealing with.
Sorry so big but yea saved ya lookin for it!
*******
Hi Beth,
I have just a few things to add to the discussion on mycobacteria.
There seems to be a lot of hype and often over reaction to the
diagnosis mycobacteriosis in the zebrafish community. Atypical or
nontuberculosis Mycobacterium spp. are ubiquitous in aquatic
environments, persisting largely in biofilms. I would argue that if
you look hard enough, you will find it in all established zebrafish
systems. Many Mycobacterium spp. are resistant to common chlorine
disinfection. That's why it is also commonly found in municipal
drinking water distribution systems and swimming pools. A number of
these Mycobacterium spp. are documented pathogens of zebrafish,
however, they are opportunist pathogens causing chronic infections.
Asymptomatic carriers of mycobacteria are common in zebrafish with
the swimbladder and ovary being the most commonly infected organs.
There are strains of zebrafish that are more susceptible to
mycobacteria infections. In our experience, the TU strain is ten
times more likely to be infected compared to other wild-type strains.
There also appears to be some differences in virulence between the
different species and strains of Mycobacterium.
So with this background, what do you do? I am not a proponent of
nuking systems and starting over. You will most likely get the same
bug back. All Mycobacterium spp. respond poorly to antibiotics, so
this is also not a good option for fish facilities. Because of the
opportunist nature of bacterial infections in fish, your first focus
should be on husbandry and water quality. Stress lowers the immune
competency of fish. This includes any type of suboptimal water
quality (e.g. elevated nitrogenous compounds - including nitrate, pH
fluctuations) and other stressors (e.g. high stocking density, over
use). The other focus should be on lowering the exposure dose. All
pathogens have a dose response - the higher the exposure to
mycobacteria the greater the infection rate. To decrease the dose of
bacteria make sure that your UV is properly sized and maintained,
that cleaning procedures are adequate, and do not keep moribund
(sick) or old fish. Eliminating Mycobacterium from zebrafish systems
is not a realistic goal, it needs to be managed.
Let me know if you have questions. We are also always happy to give
feedback on your husbandry and water quality parameters. very best, -Jen
Jennifer L. Matthews, DVM, PhD
Zebrafish International Resource Center
Pathology and Health Services
5274 University of Oregon
Eugene, OR 97403-5274 (()
(541) 346-6028 ext. 14 (()
Fax (541) 346-6151
On Jan 23, 2007, at 8:07 AM, wrote:
I work in a facility that is trying to establish a small Medaka and
Zebra fish colony.
Recently we discovered Mycobacteria in our Medaka which are on the
same
rack as our Zebrafish. One of the male Zebrafish began swimming a bit
oddly and his abdomen became red as if bleeding internally or inflamed
organs. He is has since been set to the pathologist for screening, but
is assumed to have Mycobacteria as well.
The facility Veterinarian and I have both done literature searches but
find not treatment. Has anyone successfully treated or eliminated
Mycobacteria from their fish and or system?
Help is greatly appreciated from an inexperienced fish researcher.
Beth Padnos
_______________________________________________
Zbrafish mailing list
http://www.bio.net/biomail/listinfo/zbrafish
Hi,
You can also try to use some Kanamycin sulfate. You can purchase it at
aquaticeco. Before treatment shut down your UV bulbs and remove the
carbon from your filtration system. However it might not be very
realistic to treat the whole system for a couple of fish since you will
destroy all the bacteria ( nitrosoma and Nitrobacter) from your
filtration and endanger the all population of fish..
Olivier Paugois
Whitehead Institute
9 Cambridge Center
Cambridge,MA 02142
Tel: 617-258-5200
On Jan 23, 12:07 pm, "christian lawrence"
wrote:
The veterinarians that monitor this list may have different opinions on
how
to proceed (and correct me if I have made technical misstatements), but I
would make the following GENERAL statements, based on experience:
1. If Mycobacteriosis is in your system, it is difficult, if not
impossible
to eliminate without "nuking" the system: sacrificing all of the fish,
breaking down and sterilizing the system and components and starting over
with SPF (or at least Myco free) fish.
2. If a facility has has Myco in the past, and it hasn't been "nuked", it
still has Myco, even if things have since "cleared up" (no mass
mortalities).
3. I think it not a crazy to guess that many populations of fish from
long-term facilities carry one or more strains of Mycobacteriosis - even
though personnel may be completely and blissfully unaware of it (I would
love to see a wide-scale pathology study done on random samples from many
places). The better the "conditions" (environment, diet, and genetics)the
more chronic, low level the presentation of these strains Myco will be
(will
knock out only old or otherwise immunocompromised fish). The worse the
conditions are, the more acute the outbreak. If your fish experience a
big
negative environmental effect, the low level, chronic Myco can easily
become
an all-out severe outbreak.
4. If you get fish from another lab, anywhere, that isn't certified SPF
(ZIRC is for certain diseases, including Myco, I think, but who else?) you
may very well be bringing in Myco, since as far as I know, bleaching eggs
(particularly the brief exposure typical of most protocols) is not 100%
effective at getting rid of it.
5. There may be problems if a different strain of Myco gets into a new
environment - from what I understand, the levels of virulence can depend
on
the environment and populations infected.
What does all of this mean, relative to your situation? If you're having
a
high level mortality event, and like most people, cannot afford to "nuke"
the system and start over, I would do my very best to ensure that ALL
environmental parameters are favorable and stable, cull aggressively, cut
back on feeding, slowly lower the temp a few degrees and maybe up the
salinity a bit and hope for the best. If you're not experiencing high
level mortality, and routine pathology revealed that one of your normal,
baseline level morts was infected with Myco, it certainly isn't cause for
a
dance party, but I wouldn't worry too much about it. I would just strive
to
ensure that husbandry protocols are optimal and stable and move on
(carefully).
The fact that you say that you're trying to establish a colony suggests
that
environmental parameters may not yet be stable. If this is the case,
stabilization at favorable levels is absolutely key to solving the acute
mortality problems that you may be experiencing.
Good luck,
Chris
Christian Lawrence
Brigham and Women's Hospital
Karp Family Research Laboratories 06-004B
One Blackfan Circle
Boston, Massachusetts 02115
Tel: 617.355.9041
Fax: 617.355.9064
-----Original Message-----
From:
] On Behalf Of
Sent: Tuesday, January 23, 2007 11:08 AM
To:
Subject: [Zbrafish] Mycobacteria
I work in a facility that is trying to establish a small Medaka and Zebra
fish colony.
Recently we discovered Mycobacteria in our Medaka which are on the same
rack
as our Zebrafish. One of the male Zebrafish began swimming a bit oddly
and
his abdomen became red as if bleeding internally or inflamed organs. He is
has since been set to the pathologist for screening, but is assumed to
have
Mycobacteria as well.
The facility Veterinarian and I have both done literature searches but
find
not treatment. Has anyone successfully treated or eliminated Mycobacteria
from their fish and or system?
Help is greatly appreciated from an inexperienced fish researcher.
Beth Padnos
_______________________________________________
Zbrafish mailing list
/biomail/listinfo/zbrafish
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THE SENDER AND THE PRIVACY OFFICER, AND PROPERLY DISPOSE OF THIS
INFORMATION.
The veterinarians that monitor this list may have different opinions on how
to proceed (and correct me if I have made technical misstatements), but I
would make the following GENERAL statements, based on experience:
1. If Mycobacteriosis is in your system, it is difficult, if not impossible
to eliminate without "nuking" the system: sacrificing all of the fish,
breaking down and sterilizing the system and components and starting over
with SPF (or at least Myco free) fish.
2. If a facility has has Myco in the past, and it hasn't been "nuked", it
still has Myco, even if things have since "cleared up" (no mass
mortalities).
3. I think it not a crazy to guess that many populations of fish from
long-term facilities carry one or more strains of Mycobacteriosis - even
though personnel may be completely and blissfully unaware of it (I would
love to see a wide-scale pathology study done on random samples from many
places). The better the "conditions" (environment, diet, and genetics)the
more chronic, low level the presentation of these strains Myco will be (will
knock out only old or otherwise immunocompromised fish). The worse the
conditions are, the more acute the outbreak. If your fish experience a big
negative environmental effect, the low level, chronic Myco can easily become
an all-out severe outbreak.
4. If you get fish from another lab, anywhere, that isn't certified SPF
(ZIRC is for certain diseases, including Myco, I think, but who else?) you
may very well be bringing in Myco, since as far as I know, bleaching eggs
(particularly the brief exposure typical of most protocols) is not 100%
effective at getting rid of it.
5. There may be problems if a different strain of Myco gets into a new
environment - from what I understand, the levels of virulence can depend on
the environment and populations infected.
What does all of this mean, relative to your situation? If you're having a
high level mortality event, and like most people, cannot afford to "nuke"
the system and start over, I would do my very best to ensure that ALL
environmental parameters are favorable and stable, cull aggressively, cut
back on feeding, slowly lower the temp a few degrees and maybe up the
salinity a bit and hope for the best. If you're not experiencing high
level mortality, and routine pathology revealed that one of your normal,
baseline level morts was infected with Myco, it certainly isn't cause for a
dance party, but I wouldn't worry too much about it. I would just strive to
ensure that husbandry protocols are optimal and stable and move on
(carefully).
The fact that you say that you're trying to establish a colony suggests that
environmental parameters may not yet be stable. If this is the case,
stabilization at favorable levels is absolutely key to solving the acute
mortality problems that you may be experiencing.
Good luck,
Chris
Christian Lawrence
Brigham and Women's Hospital
Karp Family Research Laboratories 06-004B
One Blackfan Circle
Boston, Massachusetts 02115
Tel: 617.355.9041
Fax: 617.355.9064
-----Original Message-----
From:
] On Behalf Of
Sent: Tuesday, January 23, 2007 11:08 AM
To:
Subject: [Zbrafish] Mycobacteria
I work in a facility that is trying to establish a small Medaka and Zebra
fish colony.
Recently we discovered Mycobacteria in our Medaka which are on the same rack
as our Zebrafish. One of the male Zebrafish began swimming a bit oddly and
his abdomen became red as if bleeding internally or inflamed organs. He is
has since been set to the pathologist for screening, but is assumed to have
Mycobacteria as well.
The facility Veterinarian and I have both done literature searches but find
not treatment. Has anyone successfully treated or eliminated Mycobacteria
from their fish and or system?
Help is greatly appreciated from an inexperienced fish researcher.
Beth Padnos
_______________________________________________
Zbrafish mailing list
http://www.bio.net/biomail/listinfo/zbrafish