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This article was published in 1981
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Inherited Enzyme Deficiencies

P.J. Healy, B.V.Sc., PhD., M.A.C.V.Sc., Veterinary Research Station, NSW Dept. of Agriculture, Glenfield

Mannosidosis (alpha)

Testing of stud Angus cattle is now undertaken in all States, with the exception of Queensland (VRS tests samples from Queensland cattle). It is expected that all stud herds will be tested by 1/1/82 the date that the Angus Society will enforce a rule that only homozygous normal calves can be registered.

In New South Wales approximately 75% of registered cattle have been tested and a similar percentage of registered Queensland cattle. On average we have found approximately 5% of animals to be carriers, but very few in Queensland.

Beta mannosidosis

A lethal inherited lysosomal storage disease of Anglo Nubian kids. Inherited in an autosomal recessive manner, homozygous recessive animals affected heterozygotes, clinically normal. The disease occurs due to a deficiency of B-mannosidase, heterozygotes have a partial deficiency in serum or plasma.

Kids affected with the disease are bright and alert, can apparently see and hear but are unable to stand. With care and hand feeding may survive for 3 weeks. The kids have a severe abduction of the forelimbs, depressed limb with crawl reflexes but a strong sucking reflex. Kids that survive for a week or so may develop nystagmus and a head tremor.

Generalised glycogenesis (Pompes disease)

Another lysosomal storage disease, inherited in an autosomal recessive manner and due to a deficiency of acidic alpha glucosidase. The disease has been reported in Beef Shorthorn cattle in WA and Brahmans in Queensland. A survey of Brahman bulls slaughtered at Queensland abattoirs has shown that between 4 and 8% were heterozygous for this condition. From this we could predict a mortality rate of 0.1% due to generalised glycogenesis in Queensland Brahmans.