Enteric redmouth disease, or simply redmouth disease is a bacterial infection of freshwater and marine fish caused by the pathogen Yersinia ruckeri . It is primarily found in rainbow trout (Oncorhynchus mykiss) and other cultured salmonids. The disease is characterized by subcutaneous hemorrhaging of the mouth, fins, and eyes. It is most commonly seen in fish farms with poor water quality. Redmouth disease was first discovered in Idaho rainbow trout in the 1950s. [1] The disease does not infect humans. [1]
Some fish species serve as vectors for the disease and have subsequently spread the pathogen to other parts of the world. [1] An example is the fathead minnow (Pimephales promelas) which is responsible for the spread of redmouth disease to trout in Europe. [2] Other vectors include the goldfish (Carassius auratus), Atlantic and Pacific salmon (Salmo salar), the emerald shiner (Notropis atherinoides), and farmed whitefish (Coregonus spp.). Infections have also occurred in farmed turbot (Scophthalmus maximus), seabass (Dicentrarchus labrax), and seabream (Sparus auratus). [1] It can now be found in North and South America, Africa, Asia, and Australia, as well as Europe.
Infection can cause subcutaneous haemorrhage that presents as reddening of the throat, mouth, gill tips, and fins, and eventual erosion of the jaw and palate. Hemorrhaging also occurs on internal organs, and in the later stages of the disease, the abdomen becomes filled with a yellow fluid - giving the fish a "pot-bellied" appearance. The fish often demonstrate abnormal behavior and anorexia. Mortality rates can be high.
A presumptive diagnosis can be made based in the history and clinical signs, but definitive diagnosis requires bacterial culture and serological testing such as ELISA and latex agglutination.
Several antibiotics are available for the treatment of redmouth disease in fish. Vaccines can also be used in the treatment and prevention of disease. Management factors such as maintaining water quality and a low stocking density are essential for disease prevention.
Pelvic inflammatory disease, also known as pelvic inflammatory disorder (PID), is an infection of the upper part of the female reproductive system, namely the uterus, fallopian tubes, and ovaries, and inside of the pelvis. Often, there may be no symptoms. Signs and symptoms, when present, may include lower abdominal pain, vaginal discharge, fever, burning with urination, pain with sex, bleeding after sex, or irregular menstruation. Untreated PID can result in long-term complications including infertility, ectopic pregnancy, chronic pelvic pain, and cancer.
An infection is the invasion of an organism's body tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agents and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable disease, is an illness resulting from an infection.
Ehrlichiosis is a tick-borne disease of dogs usually caused by the rickettsial agent Ehrlichia canis. Ehrlichia canis is the pathogen of animals. Humans can become infected by E. canis and other species after tick exposure. German Shepherd Dogs are thought to be susceptible to a particularly severe form of the disease; other breeds generally have milder clinical signs. Cats can also be infected.
Ichthyophthirius multifiliis, often termed "Ich", is a parasitic ciliate described by the French parasitologist Fouquet in 1876. Only one species is found in the genus which also gave name to the family. The name literally translates as "the fish louse with many children". The parasite can infect most freshwater fish species and, in contrast to many other parasites, shows very low host specificity. It penetrates gill epithelia, skin and fins of the fish host and resides as a feeding stage inside the epidermis. It is visible as a white spot on the surface of the fish but, due to its internal microhabitat, it is a true endoparasite and not an ectoparasite.
Cellulitis is a bacterial infection involving the inner layers of the skin. It specifically affects the dermis and subcutaneous fat. Signs and symptoms include an area of redness which increases in size over a few days. The borders of the area of redness are generally not sharp and the skin may be swollen. While the redness often turns white when pressure is applied, this is not always the case. The area of infection is usually painful. Lymphatic vessels may occasionally be involved, and the person may have a fever and feel tired.
The rainbow trout is a trout and species of salmonid native to cold-water tributaries of the Pacific Ocean in Asia and North America. The steelhead is an anadromous (sea-run) form of the coastal rainbow trout(O. m. irideus) or Columbia River redband trout (O. m. gairdneri) that usually returns to fresh water to spawn after living two to three years in the ocean. Freshwater forms that have been introduced into the Great Lakes and migrate into tributaries to spawn are also called steelhead.
Fin rot is a symptom of disease or the actual disease in fish. This is a disease which is most often observed in aquaria and aquaculture, but can also occur in natural populations.
A leaf spot is a limited, discoloured, diseased area of a leaf that is caused by fungal, bacterial or viral plant diseases, or by injuries from nematodes, insects, environmental factors, toxicity or herbicides. These discoloured spots or lesions often have a centre of necrosis or cell death. Symptoms can overlap across causal agents, however differing signs and symptoms of certain pathogens can lead to the diagnosis of the type of leaf spot disease. Prolonged wet and humid conditions promote leaf spot disease and most pathogens are spread by wind, splashing rain or irrigation that carry the disease to other leaves.
Myxobolus cerebralis is a myxosporean parasite of salmonids that causes whirling disease in farmed salmon and trout and also in wild fish populations. It was first described in rainbow trout in Germany a century ago, but its range has spread and it has appeared in most of Europe, the United States, South Africa, Canada and other countries. In the 1980s, M. cerebralis was found to require a tubificid oligochaete to complete its life cycle. The parasite infects its hosts with its cells after piercing them with polar filaments ejected from nematocyst-like capsules.
Aeromonas hydrophila is a heterotrophic, Gram-negative, rod-shaped bacterium mainly found in areas with a warm climate. This bacterium can be found in fresh or brackish water. It can survive in aerobic and anaerobic environments, and can digest materials such as gelatin and hemoglobin. A. hydrophila was isolated from humans and animals in the 1950s. It is the best known of the species of Aeromonas. It is resistant to most common antibiotics and cold temperatures and is oxidase- and indole-positive. Aeromonas hydrophila also has a symbiotic relationship as gut flora inside of certain leeches, such as Hirudo medicinalis.
Dropsy is a condition in fish caused by the buildup of fluid inside the body cavity or tissues. As a symptom rather than a disease in its own right, it can indicate a number of underlying diseases, including bacterial infections, parasitic infections, or liver dysfunction.
The fathead minnow is a species of temperate freshwater fish belonging to the genus Pimephales of the cyprinid family. The natural geographic range extends throughout much of North America, from central Canada south along the Rockies to Texas, and east to Virginia and the Northeastern United States. This minnow has also been introduced to many other areas via bait bucket releases. Its golden, or xanthic, strain, known as the rosy-red minnow, is a very common feeder fish sold in the United States and Canada. This fish is best known for producing Schreckstoff.
Viral hemorrhagic septicemia (VHS) is a deadly infectious fish disease caused by Viral hemorrhagic septicemia virus. It afflicts over 50 species of freshwater and marine fish in several parts of the Northern Hemisphere. Different strains of the virus occur in different regions, and affect different species. There are no signs that the disease affects human health. VHS is also known as Egtved disease, and the virus as Egtved virus.
Aeromonas salmonicida is a pathogenic bacterium that severely impacts salmonid populations and other species. It was first discovered in a Bavarian brown trout hatchery by Emmerich and Weibel in 1894. Aeromonas salmonicida's ability to infect a variety of hosts, multiply, and adapt, make it a prime virulent bacterium. A. salmonicida is an etiological agent for furunculosis, a disease that causes sepsis, haemorrhages, muscle lesions, inflammation of the lower intestine, spleen enlargement, and death in freshwater fish populations. It is found worldwide with the exception of South America. The major route of contamination is poor water quality; however, it can also be associated stress factors such as overcrowding, high temperatures, and trauma. Spawning and smolting fish are prime victims of furunculosis due to their immunocompromised state of being.
Streptococcus iniae is a species of Gram-positive, sphere-shaped bacterium belonging to the genus Streptococcus. Since its isolation from an Amazon freshwater dolphin in the 1970s, S. iniae has emerged as a leading fish pathogen in aquaculture operations worldwide, resulting in over US$100M in annual losses. Since its discovery, S. iniae infections have been reported in at least 27 species of cultured or wild fish from around the world. Freshwater and saltwater fish including tilapia, red drum, hybrid striped bass, and rainbow trout are among those susceptible to infection by S. iniae. Infections in fish manifest as meningoencephalitis, skin lesions, and septicemia.
Bacterial cold water disease (BCWD) is a bacterial disease of freshwater fish, specifically salmonid fish. It is caused by the bacterium Flavobacterium psychrophilum, a psychrophilic, gram-negative rod-shaped bacterium of the family Flavobacteriaceae. This bacterium is found in fresh waters with the optimal growth temperature below 13⁰C, and it can be seen in any area with water temperatures consistently below 15⁰C. Salmon are the most commonly affected species. This disease is not zoonotic.
This article is about diseases and parasites in salmon, trout and other salmon-like fishes of the family Salmonidae.
Lactococcus garvieae is a known fish pathogen affecting saltwater fish in the Far East, specifically in rainbow trout, Japanese yellowtail, and grey mullet. This bacteria causes lesions in the vascular endothelium, leading to hemorrhages and petechias at the surface of internal organs. As few as 10 bacterial cells per fish can cause an infection. L. garvieae is isolated in saltwater fish in the Far East and specifically in European Rainbow Trout.
Yersinia ruckeri is a species of Gram-negative bacteria, known for causing enteric redmouth disease in some species of fish. Strain 2396-61 is its type strain.
Flavobacterium psychrophilum is a psychrophilic, gram-negative bacterial rod, belonging to the Bacteroidota. It is the causative agent of bacterial coldwater disease (BCWD) and was first isolated in 1948 during a die-off in the salmonid Oncorhychus kisutch.