Citrullinemia is a fatal neurological disorder in newborn Holstein-Friesian calves and Brown Swiss. This enzyme is responsible for converting ammonia to urea in the urea cycle. The mutation results in a disruption of the urea cycle, followed by an increase in citrulline concentration and accumulation of ammonia in toxic amounts for the body. Calves affected by citrulinemia at birth become weakened, do not assimilate food, convulsions occur leading to death.
Citrulinemia is caused by an amino acid swap in the gene leading to the formation of a premature STOP codon, rendering the enzyme non-functional. Genetically affected individuals are recessive homozygotes with two alleles of the defect. Carriers with one allele show no signs of the mutation.
| Result | Interpretation |
| CNS | SICK |
| CNC | CARRIER |
| CNF | FREE |
REFERENCES #
- Kawecka-Grochocka E., Zalewska M., Stachelek M., Rzewuska M. & Bagnicka E. (2019). Możliwości identyfikacji CARRIER i mutacji genetycznych w celu uwzględnienia w programach hodowlanych bydła mlecznego. Przegląd Hodowlany nr 2: 3-7.
- Patel R.K., Singh K.M., Soni K.J., Chauhan J.B. & Rao K.R.S. Sambasiva. (2006). Lack of carriers of citrullinaemia and DUMPS in Indian Holstein cattle. J Appl Genet 47(3), 239–242.
- Windsor P. & Agerholm J. (2009). Inherited diseases of Australian Holstein-Friesian cattle. Australian Veterinary Journal 87(5), 193–19.