Designer milk to protect against tooth decay

Researchers are immunising cows to create bacteria-busting milk products.

Agricultural researchers are immunising cows against human illnesses so they will produce milk with enhanced protective qualities for the people who drink it.

The technology, based on a process first developed by Agresearch scientist Alison Hodgkinson, is undergoing trials in which Otago's school of dentistry is assessing the potential to use a special milk to protect teeth against decay-causing bacteria.

The "hyperimmune" milk has been under development for the past year.

Liz Carpenter, a project coordinator, told a technology field day at Hamilton the technology offered scope for a range of new milk products to protect people and animals from bacteria, viruses and fungal infections.

The immunisation system boosts the IgA antibodies in milk - an important immunoglobulin for protecting infants against diseases. It is also capable of protecting the mucosal surfaces in the stomachs, intestines, lungs, nose, eyes and ears of adults.

These antibodies can be tailored to protect against specific gut or oral illnesses. Immunisation in "dry" cows could mean they would produce up to 10 times the normal amount of IgA antibodies for the full milking season.

Liz Carpenter said trials were also being carried out to protect against fungal infections, including thrush.

One way in which the dairy industry could produce higher-value products would be to manipulate the cows or their feed to provide manufacturers with specialised milk proteins.

Probably 10,000 cows immunised to protect against fungal infections would be sufficient to provide a protein powder for a mouthwash or lozenge to fend off oral thrush, by forming a barrier on the teeth, tongue and cells lining the mouth, she said.

Other possibilities were to produce milk protein powders to protect travellers against diarrhoea.

Interest in value-added niche markets was driving innovation through changes to farm systems, management or through the extraction of "bioactives" from milk.

- NZPA