AUTOSOMAL RECESSIVE GENETIC DEFECTS OF CATTLE BREEDS
In the breeding of domestic cattle, selection of economically desired traits has been the most important contemplation for the improvement of cattle, but excluding negative factors in animal production such as causative genes for inherited diseases is also essential for the genetic improvement of cattle (Kunieda 2005). Artificial insemination is an effective method for the rapid, horizontal dissemination of genes into the population. While the propagation of genes linked to positive economic traits, such as milk yield and disease resistance is desirable, the simultaneous propagation of genetic defects needs to be avoided. Since most of these genetic diseases are autosomal recessive, the phenotype of heterozygous (carrier) animals is normal. If such animals are not removed from the breeding stock, 50% of their progeny are expected to inherit the defective allele (Mukhopadhyaya et al. 2006). The level of inbreeding within livestock populations is greater than in human population; on the other hand, the prevalence of specific defects will be higher. It is probable that a high prevalence of a lethal recessive defect could occur within a particular livestock population and escape recognition. First, livestock producers accept a relatively high neonatal mortality rate without seeking a diagnosis. Second, few if any veterinary diagnostic facilities possess either the instrumentation or the analytic skills essential for investigating the vast range of potential inborn errors of metabolism. Third, national selection programs which, employed within the dairy industry tend to use production data from adult progeny in selection. Consequently, the programs would not detect differences in fetal or neonatal mortality rates among descendants of specific sires until a deleterious defect had been widely disseminated (Healy and Dennis 1993). In cattle, the presence of genetic defects like DUMPS, FXI and CVM may have an economic impact on dairy cattle industry because normal carriers can transmit the disease allele to the next generation. In Japan, a lot of Holstein Friesian bulls and semen have been imported by Japanese artificial insemination (AI) industries from USA and Canada to breed Holstein Friesian cows and heifers. It may be possible; therefore, that some of Holstein semen might carry the mutation of such genetic defects which highlight the importance of screening programs to dairy farms. Genetic disorders are caused by a hereditary change in the structure of DNA that may have a negative impact on vitality. In cattle, the autosomal recessive genetic diseases are the most often breed-specific. There are several specific genetic disorders associated with Holstein cattle, among the most important are bovine leukocyte adhesion deficiency (BLAD) and deficiency of uridine monophosphate synthase (DUMPS).
Every individual has two copies of each gene, one copy on each of the chromosome pair. The genetic diseases are caused by a single error or mutation in genes present in our genome. Some diseases require both copies of a particular gene to be damaged or mutated (recessive diseases), whereas others need only one gene copy altered (dominant diseases). The mutant gene is inherited from one of the parents in order to get the dominant disease.
The autosomal recessive genetic diseases are mostly breed-specific. Some of the autosomal recessive genetic diseases in various cattle breeds are :
- a–Mannosidosis
- Alopecia Anemia syndrome
- Arachnomelia Syndrome (spider legs)
- Bilateral Convergent Strabismus
- Bovine Chondrodysplastic Dwarfism in Japanese Brown autosomes
- Bovine Chronic Interstitial Nephritis with Diffuse Zonal breed-specific
7. Bovine Citrullinaemia is a disease of newly born Holstein disease
8.Bovine Ferrochelatase Deficiency or Bovine Protoporphyria 2001).
9.Bovine Hereditary Zinc Deficiency
10.Bovine Leukocyte Adhesion Deficiency (BLAD)
11.Bovine Spinal Dysmyelination (BSD) in cattle (Bos taurus) is in Red Brahman calves
12.Brachygnathia Inferior (parrot mouth) is a condition in multiple joints of all the four legs, with presence of cleft plate Simmental breed where the incisor teeth meet the maxillary (Greene et al., 1973).
13.Bull dog or Achondrosplasia is a congenital lethal genetic cell
14.Cardiomyopathy Progressive Disease in bovine
15. Chediak-Higashi Syndrome (CHS) is a disorder associated and itching sensation on the surface of the skin.
16.Complex Vertebral Malformation (CVM)
17. Congenital Myasthenic Syndrome (CMS)
18. Curly Calf Syndrome or Arthrogryposia (Rigid joints)
19.Deficiency of Uridine Monophosphate Synthase (DUMPS)
20.Double Muscling or Muscular Hypertrophy (MH)
21.Ehlers-Danlos Syndrome (EDS) or Dermatosparaxix
22.Factor XI Deficiency Syndrome is inherited bleeding disorder
23.Goiter is an autosomal recessive disease of Afrikander cattle
24.Hydrocephalus (water head) commonly found in beef cattle
25.Hypotrichosis or Hairlessness exists in several beef breeds of cattle.
26.Maple Syrup Urine Disease (MSUD)
27.Marble Bone or Osteopetrosis affects Angus, Hereford
28.Myoclonus (neuraxial adema)
29.Myopathy of the Diaphragmatic Muscles in Holstein-Friesian
30.Myophosphorylase Deficiency
31.Ocular Disorder
32.Pink Tooth or Congenital Porphyria
33.Platelets Bleeding Disorder
34.Polydactyly (extra toes) in various breeds
35.Pompe’s Disease / Generalized Glycogenosis Glycogen storage disease
36.Renal Dysplasia in Japanese black cattle
37.Spastic Syndrome (crampiness)
38.Spinal Muscular Atrophy in Holstein-Friesian calves
39.Syndactyly or Mule Foot is an autosomal recessive genetic disorder
40.Tibial Hemimelia is a congenital abnormality
41.Weaver Syndrome or Bovine Progressive Degenerative Myeloencephalopathy (PDME)
42.White Heifer Disease
43.β- Mannosidosis disorder occurs
