Before I continue with this Case Study I want to emphasise that I am not passing judgement on the use of vaccinations but highlighting the impact it can have. It certainly indicates how important it is to take into consideration the current metabolic health of your horse before vaccinations and to take as much preventative care as possible to minimise the risk of a metabolic (laminitic) reaction.
These four ponies were vaccinated at the same time. They have all been highly successful bare hooved, expertly managed and all in full work on a daily basis, and apart from minor balancing required on an 5-8 week basis, are virtually self maintaining. I have been their Podiatrist since 2006 so I was somewhat shocked to see the sudden changes in their very healthy hooves all displaying stress lines and deviation of the tubules on all of their hoof capsules - consistent on both fronts and hinds - and I estimated that a major 'event' had taken place approx 6-8 weeks before. Their outer walls had also deteriorated showing minor fissures and hairline slits. Their owner confirmed that they had all received their tetnus booster 6 weeks before my visit.
As with many horses and ponies they all had minor asymmetries and these usually minor asymmetries became magnified as a result of a change in their metabolism and their hoof wall matrix displayed signs of metabolic flare.
Thankfully due to the very good management by their owner, existing good hoof health and excellent control of diet and weight, they didn't show any noticeable deterioration in their physical health, or become unsound in any way, though clearly it had quite an impact. I estimate that in a couple of trim cycles they will be back to their previously healthy state with Spectrums scores in the 7/8 range out of 10 (10 being an excellent hoof).