Looking after the Older Horse
As he’s got older, he uses more, and at the moment he’s on an average of 4-5 sachets a week – enough to keep him comfortable (and galloping round his paddock like a yearling!).
Cushing’s disease (hyperadrenocorticism) is most common in older horses, and is caused by a micro-tumour in the pituitary gland. This results in an excess of circulating cortisol (a stress hormone), that causes the characteristic symptoms of abnormal fat pads (typically over the eyes and as saddle-packs), excessive drinking and urination, and increasing susceptibility to minor infections and laminitis. Ironically, the “classic” shaggy coat of the Cushingoid horse isn’t entirely due to cortisol – the presence of a tumour in the pituitary causes a malfunction in the part of the brain that controls body temperature, causing retention of a winter coat for longer. Cushing’s isn’t curable in horses, but symptoms can be partially controlled by management (regular clipping, diet and exercise control and remedial shoeing), or largely eliminated with some medications – Cyproheptadine (Periactin) may be of some use; however, Pergolide (Prascend) is highly effective, and is licensed for the treatment of Cushing’s.
Gut problems of one sort or another are also more common in older horses – these may be malabsorbtion issues, caused by thickening of the gut wall, or an increased susceptibility to colic. This may be due to a diffuse Lymphoma (a cancer of the white blood cells) which is the commonest tumour of older horses. In these cases, the key is to feed a highly digestible, high feed value ration, possibly with a probiotic to enhance digestion.
Tooth loss is also a problem in the older horse – as I discussed earlier, eventually the teeth “cup out”, at which point there’s little more that can be done, dentally. The next phase is that the tooth falls out, leaving naked gums. I remember once doing a regular tooth rasping on a 38 year old mare – I put a hand in to have a feel around, and four teeth fell out in my palm… (she actually did better once the teeth were out than she had in months!). An edentulous (toothless) horse needs a soft, ultra-high fibre diet; typically a mash made from fibre pellets or pencils. Horses can live healthily for quite some time on such a diet – however, once your horse has reached this stage, it is probably time to consider how long you can fairly keep him going.
