GAINESVILLE, Ga. — As the winter season approaches, people are taking precautions to protect themselves from illnesses that are lurking around. Likewise, poultry producers must take similar precautions to protect their flocks from getting any harmful diseases.
The USDA defines biosecurity “as everything people do to keep diseases — and the viruses, bacteria, funguses, parasites, and other microorganisms that cause disease — away from birds, property, and people.” There are two types of biosecurity constructs, structural biosecurity and operational biosecurity, according to the USDA. Structural biosecurity is the “measures used in the physical construction and maintenance of coops, pens, poultry houses, family farms, commercial farms, and other facilities.” Operational biosecurity is “practices, procedures, policies that are consistently followed by people.”
The USDA gives a list of guidelines to be followed to maintain biosecurity standards on a farm or facility. Among them include:
· Keep visitors to a minimum. Only allow those people who take care of your poultry to come in contact with your birds, this includes family and friends. Keep track of everyone who is on your property at all times. Make sure everyone who has contact with your flock follows biosecurity principles.
· Wash your hands before and after coming in contact with live poultry. In addition to potentially spreading disease from farm to farm or bird to bird, you can also spread germs such as Salmonella that can impact human health. Wash with soap and water (always your first choice). If using a hand sanitizer, first remove manure, feathers, and other materials from your hands because disinfectants will not penetrate organic matter or caked-on dirt.
· Provide disposable boot covers (preferred) and/or disinfectant footbaths for anyone having contact with your flock. If using a footbath, be sure to remove all droppings, mud or debris from boots and shoes using a long-handled scrub brush BEFORE stepping into the disinfectant footbath, and always keep it clean.
· Change clothes before entering poultry areas and before exiting the property. Visitors should wear protective outer garments or disposable coveralls, boots, and headgear when handling birds, and shower and/or change clothes when leaving the facility.
· Clean and disinfect tools or equipment before moving them to a new poultry facility. Before allowing service vehicles, trucks, tractors, or tools and equipment—including egg flats and cases that have come in contact with birds or their droppings—to exit the property, make sure they are cleaned and disinfected to prevent contaminated equipment from transporting disease. Do not move or reuse items that cannot be cleaned and disinfected such as cardboard egg flats.
· Look for signs of illness. Know the warning signs of infectious bird diseases.
· Report sick birds. Don’t wait. If your birds are sick or dying, call a local veterinarian, cooperative extensive service, or state veterinarian. Call USDA toll-free at 866-536-7593.
The USDA’s website also lists two very serious poultry illnesses: avian influenza and virulent Newcastle disease.
USDA notes that virulent Newcastle disease is “a contagious and fatal viral disease affecting the respiratory, nervous and digestive systems of birds and poultry.” Before the disease was called exotic Newcastle disease, however the name was changed. The illness is extremely virulent, and some birds will die being asymptomatic.
The Poultry Science Department of Mississippi State University has also released information on common types of poultry illnesses. Based on the information from the university, the most severe strain of virulent Newcastle disease is called Viscerotropic Velogenic Newcastle Disease (VVND). The United States strictly enforces bird exports and requires that sick birds not enter the U.S. This strain of the virus has a high mortality rate among poultry.
A much less severe strain of the disease is called Mesogenic Newcastle disease and is the most common found in the U.S. Newcastle disease is very contagious and can cause an entire flock of birds to develop the illness within three to four days. The university states that “the virus can be transmitted by contaminated equipment, shoes, clothing and free-flying birds. During the active respiratory stage, it can be transmitted through the air. The virus is not thought to travel any great distance by this method.” A bird is not a carrier of the virus after it is healthy again. The virus does not live longer than 30 days on a farm or facility.
Symptoms include, “nasal discharge, excessive mucous in the trachea, cloudy air sacs, casts or plugs in the air passages of the lungs and cloudiness in the cornea of the eye.” In younger poultry, the disease starts with trouble breathing and sneezing. After 10 to 14 days, the chicken may start to experience paralysis in one or both wings. Along with the chicken’s head and neck being twisted, it can fall to it’s back or between the legs. Mortality among younger poultry could result in no loss of chickens or the loss of the entire flock. Adult poultry primarily see respiratory issues and hardly ever see any nervous system difficulties. Nevertheless, older chickens will have a decline in their egg production. The eggs produced will be smaller in size and have a soft outer shell. Eggs will appear off-colored and unusually shaped. The mortality rate for older chickens is much lower than the younger birds, although it can be high with some strains of the virus. Symptoms in turkeys are mostly minor unless nervous system symptoms develop. If a turkey is infected with the virus, the turkey will produce eggs with a white chalky shell.
USDA adds that, “Virulent Newcastle disease is not a food safety concern. No human cases of Newcastle disease have ever occurred from eating poultry products. Properly cooked poultry products are safe to eat. In very rare instances, people working directly with sick birds can become infected with mild symptoms, such as conjunctivitis. These are easily prevented with personal protective equipment.”
Chickens are vaccinated for the disease, but turkeys are not usually vaccinated. There is no cure for virulent Newcastle disease.
“Avian influenza is caused by an influenza type A virus which can infect poultry (such as chickens, turkeys, pheasants, quail, domestic ducks, geese, and guinea fowl) and wild birds (especially waterfowl),” USDA says.
Highly pathogenic avian influenza (HPAI) virus strains can be transmitted quickly through a flock and can spread between flocks. This strain of avian flu can have a high mortality rate. Low pathogenicity avian influenza (LPAI) virus strains spread among wild birds and causes no infection. If farm poultry is affected by LPAI, symptoms are mild.