Diarrhea of adults (new)

Bovine Viral Diarrhoea and Mucosal Disease Complex (Cattle)

Local names for Diarrhoea: Luo: diep nyaroya / Kikuyu: ruharo rwa kimira / Maasai: Iinkati /

Common names: Bovine virus diarrhoea

Description: Management disease

Causes

Mucosal Disease is caused by the same virus which causes Bovine Viral Diarrhoea. Both are manifestations of infection by the same virus.

Incidence is low but mortality is high.  The virus occurs all over the world and is also widespread in Kenya. Cattle that are infected for life with Bovine Viral Diarrhoea Virus serve as a natural reservoir of virus.

(Border Disease in sheep is closely related to this disease)

Mode of spread

Transmission can occur after birth by contact with infected secretions and excretions shed by persistently infected animals. Needle transmission can occur.  - The outcome of infection varies according to the stage of pregnancy when infection occurs:

• Virus transmission to the calf during early pregnancy results in birth of infected calves, which remain infected for life and keep excreting the virus. Fifty percent of these calves develop incurable diarrhoea when they are much older (e.g. young heifers, young steers) and die within the first two years. Surviving permanently infected calves appear stunted and are prone to respiratory and intestine ailments.
• Infection during later pregnancy results in abortion, calves born with congenital malformations, (eye and brain abnormalities) or birth of normal calves.

Whatever the stage of pregnancy the cow herself will often be only mildly affected – she may have a raised temperature and scour for a few days but only occasionally develops a severe illness. It is the persistently infected calf which causes problems.

Signs of Bovine Viral diarrhea

• BVDV is immunosupressive and as as result an infected animal is much more susceptible to different other infections affecting the gut or lungs
• The virus attacks all the mucosal surfaces in the body causing inflammation and ulceration and it is the results of this which cause the symptoms seen.
• Erosions can occur throughout the intestinal tract, lesions are seen in the mouth, nose and muzzle, there is often foul smelling diarrhoea containing shreds of intestine, mucus and blood.
• Occasionally diarrhoea may be so severe as to appear like water or paralysis of the gut may occur with no sign of faecal material.
• Other signs which may occur include discharges from the nose, excessive tears and lameness due to eruptive lesions of the interdigital cleft and coronary band.
• Animals are reluctant to eat and there is drooling and even frothing from the mouth.
• Not many animals become sick at the same time but many scouring animals die no matter what the treatment.
• Mucosal Disease is the most severe form of BVD, where a persistently infected animal, usually under 2 years of age, is superinfected with active virus, the mortality is very high, death occurring within a few days of onset, with fever, dysenteric diarrhoea, lack of appetite, dehydration, ulceration throughout the gastro-intestinal tract and erosive lesions in the mouth and nose.

Diagnosis

• Diagnosis is based on the disease history, clinical signs, gross and microscopic lesions, virus isolation from tissues such as spleen, thyroid and salivary gland and examination of paired serum samples when a more than four- fold increase in antibody titre indicates recent infection.
• For diagnosis serum samples have to be sent to a laboratory outside of Kenya.

Suspect BVD when you see:

• The birth of congenitally abnormal calves,
• Unexplained abortions,
• The appearance of stunted ill calves in the herd and
• Cases of severe diarrhoea in young animals under the age of two years followed by their death must arouse a suspicion of BVD/ Mucosal Disease.

Prevention - Control – Treatment

• Never let cattle graze or be together with cattle of unknown BVD status.
• Do not buy animals (especially not pregnant or young animals) to the herd without knowing their BVD status.
• Treatment is limited to supportive therapy such as appetite stimulants, vitamins and alimentary tract astringents, such as kaolin, charcoal etc. (note that providing antibiotic cover to prevent is not acceptable from an antibiotic resistance point of view, and not from an organic point of view.)
• Persistently infected animals should be identified and removed and isolated from the breeding herd. Only virus-negative and antibody-positive animals should be retained in the herd.
• Killed vaccines are safe, but booster doses are necessary to achieve a good level of protected immunity.
• Because the disease mainly affects cattle under 2 years and since colostral immunity from BVD positive cows wanes by 6 months of age the vaccination of young stock between 6 months and 2 years of age is a logical approach – but the manufacturer’s instructions should always be followed.
• Vaccine is obtainable from the UK and the US.

Review Process 

1. Addition of Pest of small Ruminants and Nairobi Sheep Disease By Dr Hugh Cran Oct 2011
2. May 2013: Review by Dr Mario Younan (DVM, PhD), Regional Technical Advisor for VSF-Germany, working in East Africa since 1995.

Information Source links

• Barber, J., Wood, D.J. (1976) Livestock management for East Africa: Edwar Arnold (Publishers) Ltd 25 Hill Street London WIX 8LL
• Blood, D.C., Radostits, O.M. and Henderson, J.A. (1983) Veterinary Medicine - A textbook of the Diseases of Cattle, Sheep, Goats and Horses. Sixth Edition - Bailliere Tindall London. ISBN: 0702012866
• Blowey, R.W. (1986). A Veterinary book for dairy farmers: Farming press limited Wharfedale road, Ipswich, Suffolk IPI 4LG
• FAO Rome 1968: Emerging Diseases of Animals.  The Enterotoxaemias of Sheep caused by organisms of the Welch Group
• Force, B. (1999). Where there is no Vet. CTA, Wageningen, The Netherlands. ISBN 978-0333-58899-4.
• Hall, H.T.B. (1985). Diseases and parasites of Livestock in the tropics. Second Edition. Longman Group UK. ISBN 0582775140
• Hunter, A. (1996). Animal health: General principles. Volume 1(Tropical Agriculturalist) - Macmillan Education Press. ISBN: 0333612027
• ITDG and IIRR (1996). Ethnoveterinary medicine in Kenya: A field manual of traditional animal health care practices. Intermediate Technology Development Group and International Institute of Rural Reconstruction, Nairobi, Kenya. ISBN 9966-9606-2-7.
• Khan CM and Line S (2005): The Merck Veterinary Manual, 9th Edition, Merck & Co Inc Whitehouse Station NJ USA
• Martin WB (Editor)1983: Diseases of Sheep. Blackwell Scientific Publications ISBN 0-632 -01008 -8
• Mugera, Bwangamoi & Wandera 1979: Diseases of Cattle in Tropical Africa.  Kenya Literature Bureau Nairobi
• Mulei CM and Mbithi PMF (2003). Metabolic and Nutritional Diseases of Food Animals. University of Nairobi Press. ISBN 9966-846-55-7
• Onderstepoort Henning 1956: Animal Diseases in South Africa 3rd Edition
• Pagot, J. (1992). Animal Production
• Poisoning in Veterinary Practice Prof. E GC Clarke The Association of the British Pharmaceutical Industry 106 Regent Street London WIR 6DD 1975
• Sewell MMH and Brocklesby DW (editors)(1990): Handbook on Animal Diseases in the Tropics, 4th Edition 1990. Balliere and Tindall, 24-28 Oval Road, London NW1 7DX, UK. ISBN NO: 0-7020-1502-4
• The African Veterinary Handbook Mackenzie & Simpson 1964 Pitman, Nairobi
• The Merck Veterinary Manual 9th Edition Kahn & Line 2005 ISBN 0-911910-50-6
• The Organic Farmer magazine No. 50 July 2009
• The Organic Farmer magazine No. 51 August 2009
• Verdcourt & Trump Collins 1969: Common Poisonous Plants of East Africa. St James’s Place London