Approved changes (7 March 96) to the
Great Lakes Fish Disease Control Policy and Model Program (GLFC Spec. Pub. 93-1)

Page 22, Restricted Fish Diseases, Whirling Disease

No fish from any source (with the exception of disinfected eggs and spore-free transport water of well origin) shall be imported into the Great Lakes basin, unless the source has been regularly inspected and found to be free from detection of the myxosporidean parasite Myxobolus cerebralis or overt signs of whirling disease for the past two years.  If whirling disease is confirmed in any hatchery, no M. cerebralis  positive fish may be stocked into the waters of the Great Lakes basin.  All M. cerebralis positive lots of fish must be removed from the infected hatchery.  Remaining individual lots on the hatchery will be sampled at the 2% level of detection monthly for three consecutive months, 160 days after initial M. cerebralis detection.  Where younger fish or recently transferred fish are present, the 160 day period begins when such fish are exposed to the suspect water supply.  Lots of fish testing negative for M. cerebralis following the tri-monthly sampling may be stocked into the waters of the Great Lakes basin.  Such an M. cerebralis positive hatchery or lots transferred from this hatchery will carry a (SW) classification until the expiration of three consecutive negative inspections at the 5% level of detection for each lot present, over a two year period.

Page 21, Annex V,  Guidelines for the Control and Management of Disease Agents

When the Great Lakes Fish Disease Control Policy and Model Program fails to give clear guidance or when a member agency seeks an exception to the Policy and Model Program, the member agency should immediately contact the Chair of the Great Lakes Fish Health Committee.  The concerned member agency should devise and submit a management plan for review that contains the following:

a) Description of the problem that requires action
b) Proposed fish disposition
c) Facility disease management proposal
d) Subsequent hatchery operation
e) Followup disease inspection / monitoring.
The Chair or a designate will, at his or her discretion, schedule discussion of the problem through the most expedient means for the purpose of providing a consensus decision and appropriate recommendations.  These recommendations  shall be presented to the concerned member agency.  In the interim, fish shall not be released or transferred.

Page 25, Annex VI, Inspection Procedures and Methods of Diagnosis, Sample Populations

1)  The sample population for all fish is determined on the basis of lot and production environment.  Lot is defined as those fish that originated from the same brood stock during the same year and that are being raised  on the same water source.  Example:  Two egg shipments of fall-spawning rainbow trout (Oncorhynchus mykiss) received in September and December from the same hatchery are considered one lot.  Similarly, all spring-spawning rainbow trout from the same source are another lot.  However, when one part of the lot is held in an open water supply and the other in a closed water supply, each will be sampled as a separate population.  All lots of brood stock of a single species held in the same water supply may be considered one population regardless of the age of the fish.

2)  When inspecting for whirling disease, the sample population is defined as all fish in the hatchery held in the same water supply.  Samples should be weighted towards the most susceptible species and ages of fish available.  Whirling disease spores are difficult to detect in lake trout (Salvelinus namaycush)  and coho salmon (O. kisutch) and in fish larger than 30 cm (12 in.) in length and younger than 160 days.  Facilities positive for whirling disease will be sampled on a lot by lot basis as specified in paragraph one.

Comment (3 March 96) on the
Great Lakes Fish Disease Control Policy and Model Program (GLFC Spec. Pub. 93-1)

Page 23, Restricted Fish Diseases, Epizootic Epitheliotropic Disease

In view of the fact that eight years have passed since EED has been diagnosed at a lake trout facility, the Great Lakes Fish Health Committee finds the risk of disinfected egg transfers from domesticated stock facilities to other facilities to be acceptable.  We recognize that to date, no diagnostic tool is in the foreseeable future.  In view of this fact, the ban on importing or transferring eggs from wild stocks into facilities other than quarantine or isolation facilities is to be continued.

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