Sudden death occurs, usually within two hours of onset and losses can be extensive.A sudden change of diet, such as turning sheep onto significantly better grass or the introduction of high levels of concentrate feed, can trigger the disease.Typically young sheep in their first autumn and winter are affected. following the use of a dirty intramuscular injection). Death occurs rapidly. This disease is somewhat analogous to bacillary hemoglobinuria in that dormant spores of We use cookies to help provide and enhance our service and tailor content and ads. Outbreaks may occur after an event that has caused bruising or wounds (e.g. Additional clinical signs include swelling of the eyelids, and nostrils. Ewes and lambs around lambing time are particularly susceptible to gangrenous metritis and navel ill caused byThe disease in cattle typically affects muscles of the leg and back, and even the tongue or heart. Black disease is caused by Clostridium novyi type B, a bacteria that is widely distributed in the soil and frequently present in small numbers in the liver. Affected sheep often have a stained fleece due to the discoloured urine and die within 48 hours.The bacteria can be found in normal livers, however, pre-existing liver fluke infection or other liver damage can trigger the disease.At any time of the year young calves to yearlings can be affected and the disease is more likely to occur in artificially reared calves.Change of diet or greedy feeders, dirty feeding equipment (e.g. Symptoms include restlessness, inco-ordination and difficulty swallowing. Most clostridial organisms can also occur quite naturally in the gut of healthy animals. Death occurs between two hours and three days from onset of symptoms.Over-sucking and distended bellies will trigger the bacteria to multiply and produce toxins, and hence losses are most likely to occur in single lambs from good milking ewes. Infectious necrotic hepatitis is an acute toxemia of sheep that is sometimes seen in cattle and is rare in pigs and horses. Sheep develop abomasitis which usually occurs in lambs and older animals develop toxaemia (blood poisoning). A sudden change of diet, nearly always as a result of a switch from poor to lush grazing, causes the bacteria to multiply and release toxins and it may also be associated with fluke infestation at the same time.Sheep show signs of ataxia (staggering), collapse and convulsions. Similar naturally occurring disease has been reported in sheep. Muscle weakness and paralysis leads to a failure to be able to stand with early cases often mistaken as milk fever.Most cattle will die, although slaughter on humane grounds is often required.Sheep show signs of stiffness, ataxia (staggering/inco-ordination) excitability, and ‘head-bobbing’ followed by salivation, nasal discharge, breathing difficulties and rapid death. The frozen forage then causes inflammation of the stomach (abomasitis) and triggers the disease.With sudden death generally being the outcome of clostridial infection, treatment of these diseases – except in the very early stages – is disappointing and rarely effective.However, clostridial diseases in cattle are perfect targets for vaccination. Adult sheep and older lambs can be affected, particularly from August to March. in a cattle crush, or even muscle damage from bulling.
Fluke migration causes damage to the liver tissue, which causes a suitable environment for C.novyi type B to multiply producing powerful toxins.The time from when the animal picks up the infection to the time it shows signs of disease varies from three days to several months. Darkened areas of skin develop rapidly after death giving the disease its name.
They become reluctant to move with death usually occurring within 24-48 hours.Sporadic cases of abomasitis (inflammation of the stomach) in young calves have been reported in which this bacteria appears to be the main cause. In sheep it is associated with infected tailing, castration (including rubber rings) and shearing wounds. Each present differently but the general overall outcome is sudden death.Youngstock between six months and two years of age are usually affected, with most cases occurring at grass. The edema may migrate to ventral regions such as the throat. In fact, when conditions are favourable, some organisms can even multiply in the soil. Good hygiene practices will reduce the threat of infection.This sudden death presentation is seen at grass in young adults of one or two years old from February to May or 6-8 month old finishing lambs in the Autumn.