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Department of Agriculture, Environment and Rural Affairs Department of Agriculture, Environment and Rural Affairs An Roinn Talmhaíochta, Comhshaoil agus Gnóthaí Tuaithe Depairtment o' Fairmin, Environment an' Kintra Matthers

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  • Enzootic bovine leukosis

    Topics:
    • Animal Health, Welfare and Trade, 
    • Animal diseases

    Enzootic bovine leukosis (EBL) is a disease of cattle caused by the bovine leukaemia virus (BLV), a member of the family Retroviridae. Cattle may be infected at any age, including the embryonic stage. Most infections are subclinical, but a proportion of cattle (~30%) over 3 years old develop persistent lymphocytosis, and a smaller proportion develop lymphosarcomas (tumours) in various internal organs. Natural infection has also been recorded in water buffaloes and capybaras.

    If notifiable disease is suspected, contact the DAERA Helpline on 0300 200 7840 or your local DAERA Direct Regional Office. Failure to do so is an offence.

    Clinical signs

    Most infected cattle will show no sign of the disease, but clinical signs can include:

    • tumours in many parts of the body, which can appear as bumps in the skin
    • problems digesting food and loss of appetite and weight
    • weakness, fever and abnormal breathing
    • fall in milk production
    • bulging eyes
    • diarrhoea or constipation
    • partial paralysis of the hind legs

    Internal tumours may only become apparent once cattle have been killed and butchered, so abattoir workers should look out for them.

    How is the disease transmitted?

    • from cows to baby calves during pregnancy or when suckling
    • between animals in close contact
    • through infected blood on surgical equipment and gloves

    Anyone suspecting Enzootic bovine leukosis must immediately inform their local Divisional Veterinary Office.

    More useful links

    Enzootic bovine leukosis - WOAH - World Organisation for Animal Health

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