Bovine spongiform encephalopathy: A review of current knowledge and challenges

Bovine spongiform encephalopathy (BSE), also referred to as mad cow disease, is a chronic degenerative disease that affects the central nervous system. BSE is caused by a misfolded isoform of the prion protein, a widely expressed glycoprotein. The illness is referred to as Variant Creutzfeldt-Jakob disease (vCJD) in humans. In the United Kingdom (UK), BSE in cattle was first discovered in 1986. Based on epidemiological data, it appears that animal feed containing tainted meat and bone meal (MBM) as a source of meat protein is the common cause of the BSE outbreak in the UK. Clinical indicators in cows include irregular body posture, incoordination, difficulty in standing, weight loss, and temperamental changes, including agitation and hostility. Feeding livestock MBM obtained from BSE-infected livestock contaminated with BSE prions is the only known risk factor for BSE development. Strong evidence linking BSE to human transmission and a variant type of CJD has brought the disease to the attention of many countries. Screening living animals for BSE is challenging. In most cases, suspected animals are usually killed. Typically, the central nervous system is examined for prions to diagnose this illness. There is currently no robust treatment for BSE. The prevention of BSE can be achieved by avoiding the feeding of susceptible animals with ruminant tissues that might carry prions.