Originally from: Bill
                        
I'm stickong with tetany, Val and Frances. The substratum in the Buxton area is carboniferous limestone so the animal was reared on a high calcium diet. Tetany can explain colic, head pressing, and bloating whereas other explanations cannot.

Nutritional explanations are never popular with vets who largely failed to recognise tetany in domestic pets following the substitution of sugars for bone
 meal by pet-food companies post 1996 (subsequent to the BSE scare). Tetany was mostly being misdiagnosed as epilepsy, due to the poor creatures writhing in agony because of muscle convulsions. Thankfully most pet-food companies realised the errors of their ways and are now adding minerals.

You may have noted that many types of pet-food now have copper added, and of course apart from cancer prevention one of copper's principle roles is involvment in the metabolism of calcium and phosphorous. (including prevention of excessive leaching of calcium from bone when the diet is calcium deficient).

All the best,
Bill.