Listeriosis in animals
Encyclopedia
Listeriosis is an infectious
but not contagious disease
caused by the bacterium Listeria monocytogenes, far more common in domestics animals (domestic mammals and poultry
), especially ruminant
s, than in human beings. It can also occur in feral animals—among others, game animals—as well as in poultry
and other bird
s.
The causative bacterium lives in the soil and in poorly made silage
and is acquired by ingestion. It is not contagious; over the course of 30-year observation period of sheep disease in Morocco
, the disease only appeared in the late 2000s when feeding bag-ensiled corn became common. Moreover, in Iceland
, the disease is called "silage sickness".
The disease is usually sporadic, but can occur as farm outbreaks in ruminants.
Three main forms are usually recognized throughout the affected species:
Listeriosis in animals can rarely be cured with antibiotic
s (tetracycline
s, chloramphenicol
) when diagnosed early, in goats, for example, by treating upon first noticing the disease's characteristic expression in the animal's face, but is generally fatal.
and head
.
Infectious disease
Infectious diseases, also known as communicable diseases, contagious diseases or transmissible diseases comprise clinically evident illness resulting from the infection, presence and growth of pathogenic biological agents in an individual host organism...
but not contagious disease
Contagious disease
A contagious disease is a subset category of infectious diseases , which are easily transmitted by physical contact with the person suffering the disease, or by their secretions or objects touched by them....
caused by the bacterium Listeria monocytogenes, far more common in domestics animals (domestic mammals and poultry
Poultry
Poultry are domesticated birds kept by humans for the purpose of producing eggs, meat, and/or feathers. These most typically are members of the superorder Galloanserae , especially the order Galliformes and the family Anatidae , commonly known as "waterfowl"...
), especially ruminant
Ruminant
A ruminant is a mammal of the order Artiodactyla that digests plant-based food by initially softening it within the animal's first compartment of the stomach, principally through bacterial actions, then regurgitating the semi-digested mass, now known as cud, and chewing it again...
s, than in human beings. It can also occur in feral animals—among others, game animals—as well as in poultry
Poultry
Poultry are domesticated birds kept by humans for the purpose of producing eggs, meat, and/or feathers. These most typically are members of the superorder Galloanserae , especially the order Galliformes and the family Anatidae , commonly known as "waterfowl"...
and other bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
s.
The causative bacterium lives in the soil and in poorly made silage
Silage
Silage is fermented, high-moisture fodder that can be fed to ruminants or used as a biofuel feedstock for anaerobic digesters. It is fermented and stored in a process called ensiling or silaging, and is usually made from grass crops, including corn , sorghum or other cereals, using the entire...
and is acquired by ingestion. It is not contagious; over the course of 30-year observation period of sheep disease in Morocco
Morocco
Morocco , officially the Kingdom of Morocco , is a country located in North Africa. It has a population of more than 32 million and an area of 710,850 km², and also primarily administers the disputed region of the Western Sahara...
, the disease only appeared in the late 2000s when feeding bag-ensiled corn became common. Moreover, in Iceland
Iceland
Iceland , described as the Republic of Iceland, is a Nordic and European island country in the North Atlantic Ocean, on the Mid-Atlantic Ridge. Iceland also refers to the main island of the country, which contains almost all the population and almost all the land area. The country has a population...
, the disease is called "silage sickness".
The disease is usually sporadic, but can occur as farm outbreaks in ruminants.
Three main forms are usually recognized throughout the affected species:
- encephalitisEncephalitisEncephalitis is an acute inflammation of the brain. Encephalitis with meningitis is known as meningoencephalitis. Symptoms include headache, fever, confusion, drowsiness, and fatigue...
, the most common form in ruminants - late abortionAbortionAbortion is defined as the termination of pregnancy by the removal or expulsion from the uterus of a fetus or embryo prior to viability. An abortion can occur spontaneously, in which case it is usually called a miscarriage, or it can be purposely induced...
- gastro-intestinal septicemia with liver damage, in monogastricMonogastricA monogastric organism has a simple single-chambered stomach, whereas ruminants have a four-chambered complex stomach. Examples of monogastric animals include omnivores such as humans, rats and pigs, carnivores such as dogs and cats, and herbivores such as Horses and rabbits. Herbivores with...
species as well as in preruminant calves and lambs
Listeriosis in animals can rarely be cured with antibiotic
Antibiotic
An antibacterial is a compound or substance that kills or slows down the growth of bacteria.The term is often used synonymously with the term antibiotic; today, however, with increased knowledge of the causative agents of various infectious diseases, antibiotic has come to denote a broader range of...
s (tetracycline
Tetracycline antibiotics
Tetracyclines are a group of broad-spectrum antibiotics whose general usefulness has been reduced with the onset of bacterial resistance. Despite this, they remain the treatment of choice for some specific indications....
s, chloramphenicol
Chloramphenicol
Chloramphenicol is a bacteriostatic antimicrobial that became available in 1949. It is considered a prototypical broad-spectrum antibiotic, alongside the tetracyclines, and as it is both cheap and easy to manufacture it is frequently found as a drug of choice in the third world.Chloramphenicol is...
) when diagnosed early, in goats, for example, by treating upon first noticing the disease's characteristic expression in the animal's face, but is generally fatal.
Listeriosis in sheep
In sheep, the disease is also called the "circling disease". The most obvious signs for the veterinarians are neurological, especially lateral deviation of the neckNeck
The neck is the part of the body, on many terrestrial or secondarily aquatic vertebrates, that distinguishes the head from the torso or trunk. The adjective signifying "of the neck" is cervical .-Boner anatomy: The cervical spine:The cervical portion of the human spine comprises seven boney...
and head
Head
In anatomy, the head of an animal is the rostral part that usually comprises the brain, eyes, ears, nose and mouth . Some very simple animals may not have a head, but many bilaterally symmetric forms do....
.