Myophosphorylase deficiency (glycogen storage disease Type V) in a herd of Charolais cattle in New Zealand: confirmation by PCR-RFLP testing.
OBJECTIVE
To describe a disease of muscle in Charolais calves and confirm the putative diagnosis of inherited myophosphorylase deficiency.


METHODS
Variously stained paraffin sections of muscle prepared from affected calves were used to describe the lesions. A polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) test was developed and applied to affected calves, their sires, dams and other individuals.


RESULTS
The lesions were those of rhabdomyolysis of skeletal muscles and sub-sarcolemmal spaces in normal fibres. The PCRRFLP test confirmed the expected mutation for phosphorylase deficiency of Charolais cattle in two affected calves. In addition, sires, dams and other closely-related individuals of four affected calves tested as heterozygous for the mutation. Other apparently unrelated animals also tested as heterozygous.


CONCLUSIONS
The diagnosis of myophosphorylase deficiency was confirmed. The PCR-RFLP test is suitable for use in controlling this recessively-inherited disorder as it can diagnose heterozygous individuals that are otherwise clinically normal.
Johnstone
A C
AC
Institute of Veterinary Animal and Biomedical Sciences, Massey University, Private Bag 11222, Palmerston North, New Zealand.
McSporran
K D
KD
Kenny
J E
JE
Anderson
I L
IL
Macpherson
G R
GR
Jolly
R D
RD