α-mannosidosis is a lethal genetic condition affecting Angus, Murray Grey and Galloway cattle. There are two versions of the condition caused by two separate genetic mutations, one affects Angus and Murray Grey animals; the other affects the Galloway breed. These two mutations cause the same disease and both affect the same gene¹. Affected calves express a number of symptoms including head tremors, uncoordination, aggression, nervousness and failure to thrive^1,7. Most calves die shortly after birth or within the first year and some are aborted during pregnancy.

The recessive disease was first described in Australia in Angus animals by Whittem and Walker in the late 1950s². Since then the disease has been discovered all over the world including North America⁵, New Zealand and Scotland⁶, where it is believed to have originated.

In the 1970s controls were put in place to reduce the frequency of α-mannosidosis in Australian populations and it is now estimated that 400 Angus calves are at risk of inheriting the disease every year. This number is expected to be much higher in Galloways⁸. Continued testing is still required to ensure the prevalence of carrier animals is kept to a minimum. It may never be possible to completely remove carrier animals from the breed populations world wide.

More than 20 years after α-mannosidosis was first described, with major advances in technology, a DNA test was produced for both the Angus and the Galloway mutation¹. This test is currently available through Pfizer Animal Genetics.

Testing for α-mannosidosis in Angus and Galloway cattle:
Samples for testing may be submitted in one of the following forms:

• Hair follicles. When sending hair samples, please make sure at least 25 follicles (bulb intact) are included to ensure an adequate volume of DNA to complete the test.
• Blood FTA® cards.
• Semen samples.
• Whole blood samples in purple-topped tubes

References and official α-mannosidosis documents:
1. Berg, T., Healy, P., Tollersrud, O., & Nilssen, Ø., (1997). Molecular heterogeneity for bovine α-mannosidosis: PCR based assays for detection of breed-specific mutations. Research in Veterinary Science 63: 279-282
2. Whittem, J., & Walker, D., (1957). “Neuronopathy” and “pseudolipidosis” in Aberdeen Angus Calves. Journal of Pathology and Bacteriology 74: 281-288
3. http://omia.angis.org.au/retrieve.shtml?pid=20
4. Jolly, R., Digby, J., Rammell, C., (1974). A mass programme of Angus cattle for the mannosidosis genotype. Prototype programme for control of inherited diseases in animals. New Zealand veterinary journal 22: 218-222
5. Leipold, H., Smith, J., Jolly, R., and Eldridge, F., (1979). Mannosidosis of Angus calves. Journal American Veterinary Medical Association 175(5): 457-459
6. Jolly, R., and Hartley, W., (1977). Storage diseases of domestic animals. Australian Veterinary Journal 53: 1-8
7. Hocking, J., Jolly, R., and Batt, R., (1972). Deficiency of α-mannosidase in Angus Cattle: An inherited lysosmal storage disease. Biochem. J. 128: 69-78
8. Healy, P., (1996). Testing for undesirable traits in cattle: an Australian perspective. Journal of Animal Science 74: 917-922