Animal diseases and prevention
Learn how to report and respond to avian influenza, equine botulism, and more
Preventing spread of diseases
Biosecurity refers to everything people do to keep diseases – and the viruses, bacteria, funguses, parasites, and other microorganisms that cause diseases – away from birds, livestock (cattle, swine, sheep, goats), property, and people. Biosecurity measures can include keeping visitors to a minimum, changing clothes before entering areas, cleaning tools or equipment before moving them to a new facility, and more.
Anyone involved with poultry or livestock production, from a small backyard to a large commercial producer, should review their biosecurity activities to ensure the health of their animals. USDA’s Animal and Plant Health Inspection Services (APHIS) has materials about biosecurity, including videos, checklists, and toolkits available online .
Types of Diseases
In general, there are four major categories of diseases that can affect livestock. Some are considered high-consequence, meaning they spread rapidly from animal to animal/herd to herd, and are expensive and difficult to eradicate. The response to high-consequence diseases involves various state and federal agencies in the efforts to control the further spread.
Zoonotic
A disease that can be passed directly or indirectly between animals and humans. Domestic animals, wild animals and insect species are the common link as either the origin, a reservoir (animal or insect that carries an infectious agent but is not harmed by it) or vector (disease acquired from blood-feeding insects). Some examples of zoonotic diseases include rabies, anthrax, West Nile virus, Lyme disease and salmonellosis.
Reportable Diseases/Foreign Animal Diseases
A reportable animal disease is one that, by law, must be reported to state and/or federal animal or public health officials, typically by a livestock producer's veterinarian. Reportable means that the United States Department of Agriculture Animal and Plant Health Inspection Service (USDA APHIS) has a control or eradication program in place for the disease. Reporting helps identify disease outbreaks, limits their spread, and minimizes the economic and health impacts on animals and people. These diseases are high risk with severe economic, animal health, and often public health consequences. Examples of reportable diseases include brucellosis, scrapie, bovine tuberculosis, pseudorabies, New World screwworm, and vesicular stomatitis.
Among reportable diseases are foreign animal diseases (FAD), also called transboundary animal diseases. These are also high-risk animal diseases that are not normally present in the United States or have been previously eradicated. Foot and mouth disease, highly pathogenic avian influenza, African swine fever, classical swine fever and virulent Newcastle disease are classified as "Tier 1" (highest risk level) foreign animal diseases by the USDA.
Endemic Diseases
Endemic is the constant presence and/or commonness of a disease or infectious agent in animals within a geographic area. Anthrax is endemic in limited areas of the western and midwestern United States, for example. Other levels of disease, such as epidemic, refer to an often sudden increase in the number of cases of a disease above what is normally expected in a population in a location. Outbreak carries the same definition as epidemic but is often used for a more limited geographic area. Sporadic refers to a disease that occurs infrequently and irregularly.
Emerging Diseases
A disease can be considered "emerging" if it is newly identified or previously unknown, causes disease, infection, or infestation in animals, and has the potential to result in significant animal or public health impacts. It might also be a previously known disease that has changed in some way, either by an increased ability to cause disease, an expanded host range, a change in geography, and/or causing unexpected sickness and death. West Nile virus, avian influenza, and porcine epidemic diarrhea virus are some examples of emerging diseases.
Reporting diseases
Contact our Veterinary Health Division to report concerning diseases.
Title 7 - §105. Requiring the Reporting of Contagious Diseases (Formerly §121)
A. All veterinarians practicing veterinary medicine in this state shall report any of the diseases listed in this Section to the state veterinarian within 24 hours after making a diagnosis or tentative diagnosis of any such disease. The report may be made by telephone, fax, or electronic mail. The reportable diseases are classical swine fever (hog cholera), anthrax, vesicular conditions, all equine encephalomyelitis conditions, transmissible spongiform encephalopathies (including chronic wasting disease, scrapie, bovine spongiform encephalopathy), pseudorabies (Aujeszky's disease), tuberculosis, Brucellosis, rabies, strangles (Streptococcus equi equi), equine herpes virus 1, equine viral arteritis, spring viremia of carp, viral hemorrhagic septicemia, Newcastle disease and other paramyxovirus infections, avian influenza (highly pathogenic), ornithosis (chlamydiosis, psittacosis), Salmonellas (pullorum disease or fowl typhoid), infectious laryngotracheitis (other than vaccine-induced), trichomoniasis, any disease classified by USDA as a foreign animal disease, or any other disease condition which may seriously threaten any animal population of this state.
B. Reports should include the:
name, address, and phone number of the owner
location of the premises
morbidity and mortality rate at the time of reporting
number of susceptible animals in the immediate area
approximate number of animals or poultry exposed.
C. Reports of disease outbreaks will be coordinated by the state veterinarian.
D. Livestock owners who suspect the occurrence of contagious disease should immediately contact the local practicing veterinarian, area regulatory veterinarian or county agent who, in turn, will be responsible for reporting to the state veterinarian.
E. An investigation of the reported contagious disease will be made by representatives of the Livestock Sanitary Board, preferably with the veterinarian or county agent reporting the disease. If necessary to protect the animal and poultry populations, a quarantine may be imposed on involved and exposed animals and areas. The quarantine will remain in effect until the threat has been removed.
Diseases
![](data:image/svg+xml;charset=utf8,<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24"><path d="M3.9 12c0-1.71 1.39-3.1 3.1-3.1h4V7H7c-2.76 0-5 2.24-5 5s2.24 5 5 5h4v-1.9H7c-1.71 0-3.1-1.39-3.1-3.1zM8 13h8v-2H8v2zm9-6h-4v1.9h4c1.71 0 3.1 1.39 3.1 3.1s-1.39 3.1-3.1 3.1h-4V17h4c2.76 0 5-2.24 5-5s-2.24-5-5-5z"/></svg> "Link to item")
About avian influenza
Avian influenza (AI) is a virus that primarily affects bird populations. AI viruses can infect chickens, turkeys, pheasants, quail, ducks, geese, and guinea fowl, as well as a wide variety of other birds and animals.
Migratory waterfowl have proved to be the natural reservoir for this disease. There are many different strains of avian influenza that cause varying degrees of illness. The most common types of avian influenza are routinely detected in wild birds and cause little concern.
Highly pathogenic strains of avian influenza are of greater concern because they are easily spread among birds and are typically deadly to domesticated poultry.
There are currently no confirmed cases of highly pathogenic avian influenza (HPAI) in the state of Louisiana.
Avian influenza does not present a food safety risk; poultry and eggs are safe to eat when handled and cooked properly. There is no risk to the food supply, but birds from the flock will not enter the food system.
For a current HPAI situation summary, visit the Center for Disease Control and Prevention .
Reporting suspected avian influenza
If domestic poultry or other farm birds exhibit signs of avian influenza, bird owners should consult their local veterinary professional and notify state or federal animal health officials.
Birds infected with the HPAI virus may show one or more of the following signs:
Sudden death without clinical signs;
Lack of energy and appetite;
Significant decrease in water consumption
Decreased egg production or soft-shelled or misshapen eggs;
Swelling of head, comb, eyelid, wattles, and hocks;
Purple discoloration of wattles, comb, and legs;
Nasal discharge, coughing, and sneezing;
Incoordination; or
Diarrhea
Nationally, sick or dead farm birds can be reported to USDA toll-free at 1-866-536-7593, or in Louisiana, contact the LDAF Diagnostic Lab at (318) 927-3441.
How is the virus spread in birds?
Avian influenza is primarily spread by direct contact between healthy birds and infected birds and through indirect contact with contaminated equipment and materials. The virus is excreted through the feces of infected birds and through secretions from the nose, mouth, and eyes.
Contact with infected fecal material is the most common of bird–to–bird transmission. Wild ducks often introduce AI into domestic flocks raised on the range or in open flight pens through fecal contamination. Within a poultry house, transfer of the HPAI virus between birds also can occur via airborne secretions. The spread of AI between poultry premises almost always follows the movement of contaminated people and equipment. Avian influenza also can be found on the outer surfaces of eggshells. The transfer of eggs is a potential means of transmission. Airborne transmission of the virus from farm to farm is highly unlikely under usual circumstances.
Resources for poultry owners
Trichomoniasis is a venereal disease of cattle characterized primarily by early fetal death and infertility, resulting in extended calving intervals. To keep cattle safe and avoid the spread of this disease, we ask that you report any instances of bovine trichomoniasis.
You can also apply for a trichomoniasis quarantine facility.
About botulism
Botulism is a deadly disease caused by the toxins produced by the bacterium Clostridium botulinum . The botulinum toxin is a potent neurotoxin that impairs nerve function, including those of the diaphragm, leading to paralysis. When the nerves to the diaphragm are paralyzed, the affected animal stops breathing and will die as a result.
There are seven types of botulism recognized (A, B, Ca, Cb, D, E, F, and G), based on the antigenic specificity of the toxin produced by each strain. Types A, B, E, and F cause human botulism. Types A, B, C, and D cause most cases of botulism in animals. In horses, type B botulism is responsible for more than 80% of the cases. The bacterium and its spores are widely distributed in nature. They are found in soil, sediments of streams and lakes, and in the intestinal tracts of fish and mammals. The bacteria will produce toxins under the conditions of decaying plants and animals.
How horses get botulism
There are three ways a horse can get botulism:
By consuming forage or feed containing the bacteria, which will then produce the toxins in the intestinal tract (more commonly found in foals, known as shaker foal syndrome, or toxicoinfectious botulism)
By consuming feed or forage containing the pre-formed toxins of C. botulinum (known as forage poisoning)
Through wounds contaminated with the bacteria, generally puncture wounds. Wound borders will close, providing an anaerobic environment, which is a favorable condition for the bacteria to produce the toxins.
Although the incidence of the disease is low, it is of considerable concern because of its high mortality rate if not addressed and treated immediately and properly. The mid-Atlantic region of the eastern United States, and especially Kentucky, is where botulism is most commonly found, although the disease is reported worldwide. The spores of C. botulinum Type B can be found in the soil of most regions of the United States, although they are more frequently found in the northeastern and Appalachian regions. The western region is more abundant with C. botulinum type A, and type C occurs mainly in Florida.
The frequency of occurrence of foodborne botulism in humans and in horses correlates with the distribution of the types of spores in the soil.
Treatment
Treating a horse with botulism can be very costly, difficult, and often too late. It is better to prevent the disease than to treat it. Recommended treatment for botulism includes early administration of hyperimmune plasma containing antitoxin. The antitoxin binds to the toxin molecules that are free-floating in the bloodstream and neutralizes them before they bind to nerve cells, but they cannot reverse the effects of bound toxin. The bond that forms between the toxin and the nerve cell is irreversible.
The horse’s body can make new neuromuscular junctions to replace the ones that are affected by the toxins; however, this process requires 7 to 10 days. It is a challenge to keep a horse alive that is recumbent and cannot eat or drink. In adult horses, being recumbent for a few days poses a problem in itself. They can develop pressure sores, colic, muscle damage, etc. Moreover, the horse will need to be mechanically ventilated and administered supportive therapy. However, it is very difficult to keep an adult horse on a ventilator for days, as the available machines are not designed to support this workload. If the paralysis has extended to the breathing muscles of an adult horse, it is humane to euthanize it.
Prevention
Horse owners should be cautious about feeding hay that has been rained on during the harvesting phases. Roundbaled hay is particularly a risk factor when baled at excessive moisture content. Any hay with rotten or decaying material should not be fed to horses. Since the spoiled material is most likely to be internal in round hay bales, it may be impossible to visually determine this condition unless the bales are opened. If the exterior of the bale is rotten with dark discoloration and moldy or if the bales feel warm, they should not be fed to horses. An unspoiled round bale, put out for a group of horses, is generally not a problem.
There is also a risk for botulism if horses are being fed silage or haylage, especially if the fermentation process was inadequate to lower the pH to inhibit the growth of the bacteria and toxin production. Haylage, silage, and high-moisture hay are more prone to spoilage. For people who own horses and cattle, and thus feed silage to all their animals, it is important to mention that cattle are not as sensitive to botulism as horses, but they do die from this disease.
Vaccination
There is a USDA-approved vaccine available to prevent botulism. You can purchase the vaccine from your veterinarian and talk to them about the best vaccination schedule for your herd. Find a proposed vaccination schedule for foals and adult horses from the American Association of Equine Practitioners (AAEP).
Equine Piroplasmosis (EP) is a blood-borne parasitic disease that affects horses, ponies, donkeys, mules, and zebras. EP-infected animals can develop fever, anemia, yellowing of the membranes in the eyes and mouth, and dark brown to red-tinged urine. Some animals die from the disease, while others never get sick. Horses with persistent EP infections are carriers of the parasites that cause the disease and are potential sources of infection to other horses
For information on how to prevent piroplasmosis, download this factsheet .