Researchers Discover New Cattle Disease and Prevent it from Spreading

Within Danish cattle breeding the semen of one breeding bull is used to inseminate a lot of cows. Due to the many inseminations one bull can thus father thousands of calves. Therefore, it is vital to determine whether breeding bulls carry hereditary diseases.

 

This is exactly what researchers at the University of Copenhagen have just done. In a study among Holstein calves published in the scientific journal BMC Genetics they have discovered a hitherto undescribed disease among animals - a facial deformation they have chosen to call Facial Dysplasia Syndrome. The researchers have discovered the genetic mutation that is the cause of the disease among calves and traced it back to one particular breeding bull. The bull has now been put down to prevent further cases of the disease among new-born calves.

 

'We discovered that one breeding bull had developed a mutation in the cells of the semen-producing tissue, which led to the deformation among the calves. The bull passed the mutation on to 0.5 per cent of its offspring, which does not sound like much. But this bull had already fathered more than 2,000 calves and could potentially have come to father even more. All the deformed calves died or had to be destroyed because they were suffering. Therefore, it was important to discover the cause', says Professor Jørgen Agerholm from the Department of Veterinary Clinical Sciences.

 

After having received information from veterinarians of calves with facial deformations, Jørgen Agerholm went looking for more cases in his network of cattle veterinarians, including on Facebook. He then received more calves for examination.

 

DNA from the deformed calves was subjected to genetic studies, and here the researchers identified the overall part of the genome which contained a mutation not found in normal Holstein DNA. This was possible due to thorough previous mappings of normal Holstein DNA.

 

The researchers then learned that similar facial deformations are found among humans, and these are caused by mutations in the same part of the genome, more specifically the FGFR2 gene among new-born babies. This gene was sequenced in the calves' genome, and the researchers were then able to determine that a mutation in this gene had caused the disease among the calves. The human disease thus helped the researchers in the process of identifying the gene mutation.