Animals often acquire the disease when moved on to heartwater infected grazing. It is an intracellular bacteria , residing in endothelial cells and affecting the cardiovascular, respiratory and neurological systems. Cowdriosis has a huge economic impact in Africa, both in direct losses and as an obstruction to the improvement of breeding stock due to the susceptibility of introduced high producing breeds. Cowdriosis is transmitted by bont ticks , mainly of the Amblyomma genus A. Both adults and nymphs of tick species can transmit disease.
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Heartwater also known as cowdriosis , nintas, and ehrlichiosis is a tick-borne rickettsial disease of domestic and wild ruminants. The disease is spread by bont ticks , which are members of the genus Amblyomma. Affected mammals include cattle , sheep , goats , antelope , and buffalo , but the disease has the biggest economic impact on cattle production in affected areas.
The disease's name is derived from the fact that fluid can collect around the heart or in the lungs of infected animals. The disease is common in sub-Saharan Africa and some of the West Indian islands. It was first identified in sheep in South Africa in the s, and had reached the Caribbean by In the Caribbean, at least, the cattle egret has been implicated in the spread of heartwater, since it colonized the islands in the s.
Cowdriosis is notifiable to the World Organisation for Animal Health. Clinical disease is more common in young animals and non-native breeds. The clinical signs of disease are caused by an increased vascular permeability and consequent oedema and hypovolemia. The symptoms include neurological signs such as tremors and head pressing , respiratory signs such as coughing and nasal discharge, and systemic signs such as fever and loss of appetite.
Physical examination may reveal petechiae of the mucous membranes , tachycardia , and muffled heart sounds. Cowdriosis can also cause reproductive and gastrointestinal disease. It is frequently fatal. On post mortem examination , a light yellow transudate that coagulates on exposure to air is often found within the thorax , pericardium , and abdomen.
Most fatal cases have the hydropericardium that gives the disease its common name. Pulmonary oedema and mucosal congestion are regularly seen along with frothy fluid in the airways and cut surfaces of the lungs. To definitively diagnose the disease, C. During the early stages of disease, animals may be treated with sulfonamides and tetracyclines. In advanced disease, prognosis is poor. Tetracyclines can also be used prophylactically when animals are introduced into an area endemic with cowdriosis.
A live blood vaccine is available for protection of young stock, but animals may require treatment for the disease after vaccination. Ectoparasiticides , used as dips, can be used to reduce exposure the animals exposure to bont ticks. In areas endemic for heartwater, the use of dips against other ticks of domestic animals , such as Rhipicephalus Boophilus and Hyalomma species is likely, and this will usually contribute to control of vectors of E. From Wikipedia, the free encyclopedia.
Heartwater Scientific classification Kingdom: Bacteria. Trends in Parasitology. Animal and Plant Health Inspection Service. Department of Agriculture. Archived from the original on Retrieved Categories : Rickettsiales Bacteriology Ruminant diseases.
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Metrics details. The invasion of West Africa by Rhipicephalus microplus during the past decade has changed the ecological situation of the agent of heartwater Ehrlichia ruminantium in this area. Before, its local vector, Amblyomma variegatum, was the most abundant tick species found on livestock. Today, the abundance of the R. We investigated the potential of this new ecological situation to impact the circulation of E. This screening was applied on field samples of 24 R. The PCR detected E.
A serological survey in Mozambique to detect antibodies to Cowdria ruminantium , the etiologic agent of heartwater, revealed a seroprevalence of 8. Translocation of 10 serologically negative goats from Tete to farms in the south resulted in two clinical cases of heartwater that were fatal. In addition, four goats seroconverted within the study period of 5 weeks. One goat showed no symptoms. Two goats died of other causes, whereas the remaining goat went missing after 1 week. Experimental needle infections of goats and sheep were conducted to confirm results and to isolate different strains of C. These data indicate that translocation of goats from the north to the south of Mozambique bears a high risk of C.
Heartwater also known as cowdriosis , nintas, and ehrlichiosis is a tick-borne rickettsial disease of domestic and wild ruminants. The disease is spread by bont ticks , which are members of the genus Amblyomma. Affected mammals include cattle , sheep , goats , antelope , and buffalo , but the disease has the biggest economic impact on cattle production in affected areas. The disease's name is derived from the fact that fluid can collect around the heart or in the lungs of infected animals. The disease is common in sub-Saharan Africa and some of the West Indian islands.