Dr Stewart Telfer, then lecturer in Animal Nutrition at the University of Leeds, became interested in the idea of delivering trace elements in the reticulum of ruminants through a soluble glass bolus. He teamed up with a PHD student named George Zervas and with Peter Knott of the University of Leeds Ceramics Department; and the trio set about developing a soluble glass bolus containing essential trace elements. From the combination of expertise in animal nutrition and a knowledge of glass, came the development of a unique and revolutionary patent-protected soluble glass bolus, which would deliver trace elements in the rumen at a constant rate, for between 4.5 to 6 months in cattle, and up to 8 months in sheep. To this day, the boluses developed by the team remain unique in their mode of action.

The publication of the patent for the bolus formulation resulted in the team being contacted by Dr Brian Algar of Pilkington Glass Brothers. A joint University/Pilkington project ensued, which resulted in Pilkington taking over the development of the glass.

The Bimeda Telsol Cosecure and CoseIcure boluses that resulted from the team’s years of research, graft and innovation deliver copper, selenium and cobalt to the animal; trace elements which are essential for immunity and thrive. The CoseIcure boluses also deliver iodine. However, their most significant achievement in developing these boluses was their ability to provide rumen-available copper. To this day, they remain the only boluses which can provide ionic rumen available copper.

TMT results from excessive molybdenum and sulphur combining in the rumen to form thiomolybdate, which then is absorbed into the blood stream where it causes problems. TMT is commonly misdiagnosed as copper deficiency, as the clinical symptoms of spectacles and poor coat are often associated with a lack of dietary copper. However, cows and sheep with thiomolybdate toxicity (TMT) are not deficient in dietary copper.

TMT occurs when sulphur and molybdenum, which are consumed through the animal’s diet, combine in the rumen to form Thiomolybdate. Thiomolybdate is very ‘copper hungry’ and will combine with copper present in the rumen. Where there is insufficient copper in the rumen, the thiomolybdate is absorbed through the rumen wall and it will then bind with copper in the blood stream. This is where the real issue lies, as enzymes which are essential for fertility and energy utilisation require copper from the blood stream to function. When thiomolybdate binds with this copper, the enzymes are no longer able to work, and fertility and thrive are impaired.

Developing a Bolus to Prevent Thiomolybdate Toxicity (TMT)

Dr Telfer and his team realised that the key to preventing TMT lay in the rumen. If he could create a copper bolus which would supply ‘sacrificial copper’ in the rumen, the thiomolybdate would combine with this copper, and would not go in search of copper in the blood stream. TMT would be prevented and fertility and thrive would not be impaired.

Dr Telfer’s team realised that in order to provide sacrificial copper it would need to be active roughly between pH 5.5 and 6.5, which is the normal pH of the rumen.

A constant supply of rumen-available ionic copper is required, which binds with the thiomolybdate and makes it harmless; passing out of the body as faeces.