What is Marek's Disease and should I have my new chicks vaccinated when I order them? Can people get Marek's Disease from the chickens? Is the desease common? If I have our birds vacinated, is the vaccine transmitted in the eggs or meat of the bird? I really hate the thoughts of chemicals in the birds, but if it is ok and if it helps the birds health I would consider it. Also, what about that chick starter stuff you put in there water when they arrive? Does that stay in thier systems? Thanks for any info!

-- Karen (db0421@yahoo.com), July 26, 2001

Answers

hi Karen, this won't exactly answer your question, but I have raised chickens for many years, and never had any vaccinated. Whatever Mareks is, we never got it. As for the stuff for their water, we never used that either, except with the cornishx and turkeys which grow too fast for their own good...We use medicated chick starter for their first feed, then switch over to an unmedicated grower ration. If you are getting layers, you'll want to start layer crumbles by maybe four months or so.

-- mary (marylgarcia@aol.com), July 26, 2001.

Yes, do vacainate. I did not have this done and a shipment of chicks had the disease. I lost all but one, the disease also killed my turkeys. I now have this disease on my place and all chickens that come into contact with it have a chance of coming down with it. It is heart breaking to watch chick after chick come down with this terrible disease. Any chickens I get in the future will have to be vaccinated. It doesn't cost much for the vaccination, better to be safe than sorry. I have raised chickens for many years, never vaccinated, but you never know. I bought these chicks from a well known hatchery, and they carried the disease.

-- June Blue (jblue@telecom.dgs.ca.gov), July 26, 2001.

The hatcheries I deal with do not recommend vaccinating for Marek's for the small flock owner. So, I have never had it done. All my birds come from well known hatcheries or from my own hens. It's when you pick up birds from auctions, swapmeets, shows, etc., that you run into sick birds and, fortunately, I've never had a sick bird.

I don't give the chicks water when they arrive. I give them straight un-flavored Pedialyte for the first 3 days. The electrolytes help the little ones get over the trauma of their trip.

As I take each chick out of the shipping box, I dunk their beak in the liquid so they can have a good drink. They will then remember where to get a drink. I also put marbles in the waterer for the first week so the chicks don't drown. I have never had to show the chicks where the food is. They find it on their own! Do remember that chicks can live on their yolk for 3-4 days, so depending on the time it took to get your birds, they may or may not eat on arrival.

Most diseases that fowl get are host specific. Think of how long fowl have been raised!

Marek's Disease (Visceral Leukosis)

Marek's disease is characteristically a disease of young chickens but older birds can also be affected. In contrast to the lymphoid leukosis tumor response, Marek's disease may be observed in more diverse locations.

Marek's disease is caused by a virus belonging to the Herpes virus group. Much is known about the transmission of the virus; however, it appears that the virus is concentrated in the feather follicles and shed in the dander (sloughed skin and feather cells). The virus has a long survival time in dander since viable virus can be isolated from houses that have been depopulated for many months.

The usual mode of transmission is by aerosols containing infected dander and dust. Young birds are most susceptible to infection by Marek's disease; however, since the incubation period is short, clinical symptoms can appear much earlier than in the case with lymphoid leukosis.

Marek's disease may produce a variety of clinical responses, all lymphoid in character. These are acute visceral, neural, ocular, skin or combinations of the responses that can be seen.

Marek's of the visceral type is characterized by widespread involvement with lesions commonly seen in gonads, liver, spleen, kidney and occasionally heart, lungs and muscles. The disease is often acute, with apparently healthy birds dying very rapidly with massive internal tumors. The disease may appear in broiler-age birds but the most severe losses occur in replacement pullet flocks prior to onset of egg production.

The neural type of Marek's is typified by progressive paralysis of the wings, legs and neck. Loss of body weight, anemia, labored respiration and diarrhea are common symptom. If lesions are present, they are confined to the nerve trunks and plexes enervating the paralyzed extremities. Frequently no gross lesions can be observed.

Ocular (eye) leukosis or "gray-eye" is usually seen in early maturity. Morbidity and mortality are usually low but may approach twenty-five percent in some flocks. It is characterized by the spotty depigmentation or diffuse graying of the iris in the eye. The pupil develops an irregular shape and fails to react to light. Emaciation diarrhea and death follow.

Skin leukosis produces the most severe losses in broilers. The losses result from high condemnations at the processing plant. Enlargement of the feather follicles due to accumulations of lymphocytes is the typical lesion. This is the most infective virus since it is produced in the regions of the feather follicles and is shed with the skin dander.

Acute Marek's disease can be extremely rapid in its course, producing mortality in apparently healthy birds. However, in some cases the lesions may regress and clinically affected birds may make complete recoveries.

Diagnosis is based upon flock history and disease manifestations. Accurate diagnosis may depend on results of laboratory procedures. As is the case with lymphoid leukosis, there is no treatment for Marek's disease.

A vaccine is available that is extremely effective (90% +) in the prevention of Marek's disease. It is administered to day-old chickens as a subcutaneous injection while the birds are in the hatchery. Use of the vaccine requires strict accordance with manufacturer's recommendations in a sterile environment.

-- ~Rogo (rogo2020@yahoo.com), July 27, 2001.