North Carolina Veterinary Diagnostic Laboratory--Real World Example

Here is a good example of the work at the North Carolina Veterinary Diagnostic Laboratory (NCVDL). This article was taken from The NCVDL Report Volume 5 Issue 1 and written by Dr. Richard Oliver, Director of the Arden Laboratory in Fletcher.

Western North Carolina was subjected to abnormally low temperatures from late December 2009 through January 2010. Over a two week period that coincided with the onset of sub-freezing air temperatures, an owner reported losing around 30 common carp. The fish were swimming at the pond's surface while lying on their sides. The fish were able to swim away when approached. The pond had a very high stocking density with about 50,000 pounds of fish in approximately 3-acres. It had an iced over surface covered with snow during most, if not all, of this episode.

One 26-lb female carp was submitted for laboratory evaluation. She had a good amount of flesh with respect to skeletal muscle mass yet there was virtually no visceral fat present. The gastrointestinal tract was devoid of content and the majority of the body cavity was dominated by an expanded air bladder along with a vast amount of ovarian tissue which showed some indication of deterioration. Mucus scrapes and gill preps indicated low parasite numbers. Histopathology confirmed widespread, chronic ovarian degeneration. The diagnosis was Dystocia.

In spawning, fish dystocia is the lack of spawn coupled with the non-resorption of eggs in the body cavity. Ovarian swelling induces impingement on the pneumocystic duct and the fish's ability to pnuemoregulate is impaired. (The air bladder swells and can not be properly deflated--you try diving with a life preserver)! Increased pressure in the body cavity also leads to a decrease in feed consumption and ultimately, liver and kidney malfunction. The condition is greatly exacerbated by extreme cold with water temperatures below 37 ^oF being the critical point.

Special thanks to Jeffrey Hinshaw, Ph.D. Associate Professor and Extension Specialist at the Mountain Horticulture Crops Research Station for his assistance on this case. Thanks also to Dr. Richard Oliver for allowing me to post his article to my blog.

Salt as a Treatment for Fish

Salt is a common and relatively inexpensive treatment for fish. The use of non-iodized table salt or rock salt (suitable for consumption by humans or livestock) is acceptable for treatment. For ease of application, many pond owners use 50 lb salt brine blocks. "Brine" blocks are salt blocks. Granular salt can also be purchased in bags or bulk.

Seawater contains 3% (30,000 ppm) salt concentration. Two hundred ppm (200 ppm) to 500 ppm can be used as an indefinite treatment in ponds to relieve stress. Ten thousand ppm (10,000 ppm) to 30,000 ppm can be used as a prolonged treatment in tanks for 30 minutes or until fish show signs of stress. Thirty thousand ppm (30,000 ppm) can also be used as a quick dip (60 seconds) in treatment tanks. To achieve 30,000 ppm in a tank, you add 2 1/2 lbs of salt for every 10 gallons of water. For ponds, 1 ppm is equal to 2.7 lbs/acre-ft of water. You need to know how many acre-feet of water you have in your pond (surface acres x average depth) to determine the treatment rate.

Carp Pond Forum 2010

The Carp Pond Forum 2010 is scheduled for Monday, March 29 at 6:30 pm at the Cleveland County Extension Center, 130 South Post Road Suite 1, Shelby. Carp Pond owners, this is your opportunity to interact with Calvin Keith Crawford, Midway Lakes, Manuel Fredell, Creekside Carp & Catfish Lakes, and Doug Whitaker, Whit-Mar Lakes, as they lead a round table discussion on owning and operating a carp pond. Dinner will be provided with your $10 registration fee ($15 for 2). Make checks payable to: McDowell Cooperative Extension. Mail to McDowell Cooperative Extension, 60 East Court Street, Marion, NC 28752. Call Molly Sandfoss or Cheryl Mitchell at 828-652-7874 with questions. Must register by March 25.

North Carolina Wildlife Resources Commission Stocking Permit

As of July 1, 2005, anyone interested in stocking inland, public fishing waters with fish, mollusks, or crustaceans must obtain a stocking permit issued by the Wildlife Commission. The purpose of this permit is to protect native, or legally established aquatic species from the potentially damaging effects of unauthorized stockings. Fish stocked into public waters have the potential to escape into adjacent waters and create problems for existing aquatic communities by feeding on eggs, fry, or adults of existing fishes. They may compete for food and habitat. Stockings may also introduce diseases and parasites, and possibly interbreeding.

The only waters not affected by this rule are private ponds, which by statute is defined as bodies of water arising within and lying wholly upon the lands of a single owner or group of joint owners or tenants in common, and from which fish cannot escape, and into which fish of legal size cannot enter from public waters at any time.

Since most ponds in western North Carolina are built by impounding streams, they are considered public waters. The term public does not imply that the general public has the right to fish these waters without landowner permission. It means that the waters flowing through the pond are contiguous with adjacent streams.

There is NO charge from this permit. You can find out how to apply by visiting www.ncwildlife.org/fishing/fish_stocking_permit.htm or by calling 919-707-0226. I can also help you getting an application for the stocking permit.

Aquaculture Farm Tours

Two aquaculture tours to showcase aquaculture production and fee fishing will be offered on December 3 and December 7. On December 3, a tour of Grandfather Trout Farm, Banner Elk, and Hump Mountain Trout Farm, Elk Park, will take place. Grandfather Trout Farm is a fee fishing operation located in near Boone. Hump Mountain Trout Farm is a fingerling and food fish producer located in Elk Park. Both of these facilities have been in operation for years.

On December 7, a tour of Creekside Carp & Catifish Lakes and Whitmar Lakes will take place. These facilities also have been operating for years. If you ever considered aquaculture as a business venture this is your chance to see some fish farms first hand. this is your chance to talk with the business owners. A van will be available for transportation and will leave Marion at 9:30am on both days. Return time scheduled for 4:00pm on December 3 and 3:30pm on December 7. You are welcome to drive to the facilities as well. Registration is required by December 1 and cost is $5.00. Make checks payable to McDowell County Center. Space is limited, call early. Call Cheryl Mitchell or Molly Sandfoss at 828-652-7874.

Carp Pond Workshop: The Basics

Whether you are a new or seasoned carp pond operator, this training is for you. We will be discussing the basics like fish anatomy, water quality and testing, and common problems with their treatment. We will meet at the Surry County Extension Center in their Auditorium in Dobson on Monday, March 30 at 6:00 pm. There is a $5 registration fee for refreshments. Please make checks payable to McDowell County CES. Mail checks to McDowell County CES, 60 East Court Street, Marion, NC 28752, Attn: Carp Pond Meeting. Register by Thursday, March 27 by calling Cheryl Mitchell or Molly Sandfoss at 828-652-7874.

Amendment to List of Species Affected by the APHIS VHS Federal Order

On November 8, 2007, the United States Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) amended the list of species affected by the Federal Order on Viral hemorrhagic septicemia (VHS). The stakeholder announcement describing the changes to the list can be viewed at:

http://www.aphis.usda.gov/publications/

This is a direct link to the new list:

http://www.aphis.usda.gov/animal_health/animal_dis_spec/aquaculture/downloads/vhs_fed_order.pdf

Common carp is not included on this amended list. But you can view the species that are. Be aware that species are being evaluated if they are susceptible to VHS.

Comments from Meeting about NC Wildlife Regulation Changes

On December 11, 2007, a meeting was held with two North Carolina Wildlife Resource Commission biologists about proposing regulation changes on the wild harvest of common carp in North Carolina waters. Nine carp pond owners were in attendance representing 5 carp ponds. The discussion was initiated last year in response to Viral Hemorrhagic Septicemia outbreak in the Great Lakes region. In the past, many common carp have been hauled from this region and stocked into North Carolina carp ponds. Carp pond owners realized the importance of stopping the spread of this disease into North Carolina. But, it also left them with a problem of where to go now to get fish. It was suggested to try to harvest in North Carolina where the fish would not have to be transported long distances as well as keep exotic diseases out.

Here are some of the highlights of the meeting:

Common carp is classified as a non-game fish. Regulations are a less stringent since it is not considered a game fish. If it is taken for some purpose other than bait, it is regulated by a special device license. Special devices vary by county. Time of harvest vary by county. Many of these regulations originate within the county, and some regulations are politically driven.

Carp pond owners want common carp greater than 15 lbs. Twenty years ago it was common to get 19-20 lb fish. Today they average 15 lbs. Haulers are traveling as far away as South Dakota to get fish. Many of these carp are seined with mile long seines.

In North Carolina, carp were once harvested from Alligator River and the Currituck Sound. Also, harvest was permitted using 12 foot hoop nets. Now, 6 foot hoop net is permitted. Twelve foot hoop nets would be desired to harvest common carp in local lakes (Catawba chain of lakes, Yadkin and Pee-Dee chain as well).

Some carp pond owners cull their fish. Some owners cull carp 12 lbs and under.

Protocol for regulation changes:

In January, public meetings are held by the North Carolina Wildlife Resources Commission. At these meetings, proposed regulation changes can be entered into public record. Recommended regulation changes can also be sent in writing to the Wildlife Commission. They must be submitted before July. An internal review is down from staff’s recommendation and public input. Biological and enforcement staff reviews the comments where regulations are pared down. The Commissioners take staff recommendations. In January when public hearings are held, people can submit comments about proposed regulation changes.

Please feel free to comment. If you know ANY history about the harvest of common carp in North Carolina, please comment. I will add and update this post as more information is gathered.