Control of α‐mannosidosis in Angus cattle

Abstract

SUMMARY Tests for the detection of animals heterozygous for a‐mannosidosis were undertaken on samples taken from 34,203 cattle registered with the Angus Society of Australia. Results indicates 1,836 (5.4%) of the animals were heterozygotes. Heterozygotes were detected in 214 (51%) of the herds examined.

Haemopoietic chimaerism: a complication in heterozygote detection tests for inherited defects in cattle

“…The results of screening programmes conducted with the support of the respective breed societies indicate that prior to introduction of the programmes approximately 13% of registered Brahmans (McPhee & Reichmann 1990), 20% of registered Poll Shorthorns (Healy, unpublished observations) and 5.4% of registered Angus (Healy et al 1983) were heterozygous for the respective defect. The results of screening programmes conducted with the support of the respective breed societies indicate that prior to introduction of the programmes approximately 13% of registered Brahmans (McPhee & Reichmann 1990), 20% of registered Poll Shorthorns (Healy, unpublished observations) and 5.4% of registered Angus (Healy et al 1983) were heterozygous for the respective defect.…”

“…respectively. In contrast, the relative efficiency of tests for detection of heterozygotes for a-mannosidosis was found to be high, with the most frequent complication being faulty breeding records (Jolly et al 1974;Healy et al 1983). The prevalence of heterozygotes for these two defects has been reduced by utilization of heterozygote detection tests that exploit reduced activities of the respective enzymes in peripheral leucocytes of heterozygotes (Healy 1981(Healy ,1982a.…”

Haemopoietic chimaerism: a complication in heterozygote detection tests for inherited defects in cattle

“…Knowledge of the prevalence of twinning and of heterozygotes for specific defects is necessary in order to assess the likely impact of incorrect diagnoses, caused by haemopoietic chimaerism, upon disease control programmes. The results of screening programmes conducted with the support of the respective breed societies indicate that prior to introduction of the programmes approximately 13% of registered Brahmans (McPhee & Reichmann 1990), 20% of registered Poll Shorthorns (Healy, unpublished observations) and 5.4% of registered Angus (Healy et al 1983) were heterozygous for the respective defect. The prevalence of natural twinning in Australian beef cattle is probably similar to the 1% reported in North American (Rutledge 1975).…”

“…In a review of routine tests for detection of Brahmans heterozygous for generalized glycogenosis, McPhee Correspondence: P J Healy. Accepted 26 August 1993 and Reichmann (1990) concluded that the efficiency of the test was compromised by environmental factors and possibly confounded by additional genetic factors. In contrast, the relative efficiency of tests for detection of heterozygotes for a-mannosidosis was found to be high, with the most frequent complication being faulty breeding records (Jolly et al 1974;Healy et al 1983). Definition of mutations responsible for citrullinaemia and bovine leucocyte adhesion deficiency led to the development of DNA-based tests for detection of heterozygotes (Dennis et al 1989;Shuster et al 1992).…”

Lysosomal alpha-mannosidase and alpha-mannosidosis

“…The majority of the affected calves are stillborn or fail to survive the immediate postnatal period. The animals that survive show severe and progressive neurological disease characterized by tremors of the head, ataxia and aggression (71)(72).…”