Bovine Leukocyte Adhesion Deficiency

Also known as "BLAD".

Introduction

This is an autosomal recessive disorder seen in Holstein Cattle mainly in the USA and is caused by a missence mutation of -Asp-128-Gly in CD18 molecule. It is is characterised by premature death and chronic bacterial infections such as recurrent pneumonia. All animals with this mutation can be traced to sire many years ago. In the USA, around 15% of cattle have this mutation.

Affected calves will appear normal at birth but then become clinically ill within the first few weeks. Life expectancy is generally not more than one year old.

Clinical Signs

Chronic recurrent infections such as pneumonia, diarrhoea, dermatitis, gingivitis or vasulitis. The infection will always reappear, even following doses usually high enough to cure the infection.

Diagnosis

There are tests avaliable in the US to diagnose heterozygous carriers and homozygous calves.

Control

Test the herd and eliminate carrier animals.

References

Andrews, A.H, Blowey, R.W, Boyd, H and Eddy, R.G. (2004) Bovine Medicine (Second edition), Blackwell Publishing

Radostits, O.M, Arundel, J.H, and Gay, C.C. (2000) Veterinary Medicine: a textbook of the diseases of cattle, sheep, pigs, goats and horses Elsevier Health Sciences

Literature Search

Use these links to find recent scientific publications via CAB Abstracts (log in required unless accessing from a subscribing organisation).


Bovine leukocyte adhesion deficiency syndrome (BLAD): a recessive disorder in Holstein Friesian cattle - a review. Vijay Kumar; Ashwani Sharma; Agricultural Research Communication Centre, Karnal, India, Agricultural Reviews, 2009, 30, 4, pp 293-300, many ref. - Full Text Article