Monday, 29 January 2018

Rewiring the equine brain

A newspaper article took my eye today, about the capacity of the human brain to rewire itself after a brain haemorrhage.

It put me in mind of an episode from the later life of Pat (foreground), which I should perhaps record because I thought it so unusual.

When he was already quite old for a thoroughbred, Pat suffered a stroke one day while out in the field with his pals. We realised there was something wrong when he remained lying down when all the others gathered at the gate to come in to their stables.

I took a halter and went to see what was wrong. Though at that point he did not seem especially distressed, he was at first unable to get to his feet. Eventually he managed it with a struggle. Then I discovered he couldn’t walk. It took a long time to encourage him out of the field. He finally settled on a crabwise motion and seemed to have pretty well lost the use of his nearside hind leg. Once he was in his stable, other disturbing symptoms appeared.

The vet was promptly summoned. He prescribed medication and told us if the horse lived through the night he would survive. When I asked about the leg, he replied that the area of the brain controlling the nearside hind was gone beyond recovery, but another part of the brain would evolve the capacity to take over this necessary function. I’d never heard of anything like this.

Following the vet’s instructions we nursed Pat through the next couple of days in his stable and then took him out to the field. All symptoms other than the leg paralysis had now disappeared. He was even able to walk more or less in a straight line without weight-bearing on the damaged leg. However as soon as he saw his pals in the field he decided he would canter over to them. Because only one hind leg was pushing him forward he almost went sideways. This obviously surprised him, but since he could stand, walk and graze he was much happier out than in his stable.

To cut a long story short, things turned out exactly as the vet had predicted. The damaged leg had swollen and never went all the way back to its normal size and it also took a long time to heal the suppurating sore that developed on the cannon-bone while he was semi-incapacitated, but gradually he recovered the use of the leg and even the ability to canter in a straight line.

I have no idea who may be interested in this story, but I felt |I should tell it anyway.