Summer is a stressful time for hooves. Yet while the assumption might be that hot, dry weather is the culprit when it comes to this season’s hoof problems, the truth is quite different.
“Healthy hooves can cope with hot and dry conditions,” says farrier Simon Curtis, explaining that the horse’s Asiatic origins equipped him with hoof horn able to withstand roasting summers on arid, hard-baked plains.
“What they find difficult to deal with is the constant change from dry conditions to wet and back to dry.”
Simon explains that a long, hot summer is less challenging to hoof health than the more typical British combination of warm, damp spells interspersed with heavy downpours.
“The hoof is pretty good at protecting itself and regulating its own humidity,” he says. “Horses in the dry environments of the eastern Mediterranean and western states of America tend to have good horn that is shiny and hard, like cattle horn. Hooves will adapt to dry but consistent conditions, given time, but they cope less well with variable temperature and humidity.”
During repeated cycles of wet and dry weather, the hoof wall expands and shrinks with the rapidly fluctuating moisture levels. The softer horn becomes unstable and less able to carry weight.
“Superficial cracks will open up and clenches [the bent over nail head on the hoof wall] will rise,” says Simon. “Good-quality hooves will look after themselves, but poorer hooves will develop problems.
“Horn quality has a lot to do with genetics, just as some of us have stronger hair than others,” he adds. “Hooves that are ‘shelly’, with thin, weak horn, will be less able to withstand climatic changes and any fissures in the hoof wall will tend to widen.
“In dry weather, the dryness will only extend a few millimetres up the hoof wall. This can be significant, however, as this is where the nails will penetrate. On the plus side, we see fewer abscesses and puncture wounds when the ground is harder.”
A vicious cycle
So how can hooves be helped during these challenging summer months? If the feet aren’t particularly healthy in the first place, changeable weather conditions, combined with a busier workload, can be a recipe for lost shoes and split horn.
“Many varnishes affect the hoof’s natural ability to regulate its own humidity, but a hoof hardener can help protect weak hooves against climate variations,” says Simon. “Natural substances tend to be better — lanolin is good.
“A substance like this acts as a barrier and can improve moisture levels within the hoof. It is best applied immediately after shoeing, when any varnish has been rubbed off and the product can penetrate the hoof wall.
“Hosing the feet can help, as long as you’re consistent and do it every day,” adds Simon. “Wash any mud from the legs and feet, as mud will draw moisture from the hooves, but don’t lead the horse straight into paper bedding. This will stick to the hooves and will also dry them.”
Simon recommends wood shavings as a suitable bedding for horses with hoof quality issues. “Straw allows air to circulate around the hooves, but shavings are best for keeping moisture levels consistent,” he says. “As far as paddocks go, hooves like sandy soil. This might not produce much grass, but it does allow water to drain away. Standing up to the coronet bands in clay soil is what does the damage.”
The most important thing is to keep to a regular trimming and shoeing schedule in spring and summer, when hoof growth tends to increase.
“A vicious cycle can develop where the shoe becomes loose and the hoof breaks, making it harder to keep a new shoe in place,” explains Simon. “A simple farriery rule is to avoid putting nails in cracks. If nails are placed quite high, above the deteriorating horn, the cycle can be broken and more solid horn will be produced.
“Repair materials should be seen as a temporary measure and not a permanent solution, as any glue on the hoof wall can also draw moisture. Traditional good shoeing is the long-term answer.”
Coping with hard ground
A hot, dry spell can produce hard ground, another summer hoof hazard.
“When the ground is hard, the force of a horse’s weight descending through a single column [the leg] combines with the ascending ground reaction forces,” says Team GBR farrier Haydn Price. “This can compromise the hoof capsule and cause bruising.”
What’s important, explains Haydn, is to distinguish between these soft tissue problems that can make a horse footsore and a conformational development that manifests itself as skeletal overload.
“Talk to your farrier first if your horse is not liking the ground,” he says. “If protection in the first instance, in the form of pads, doesn’t solve the problem, consult your vet.”
Options for protective hoof pads vary.
“A hard, thermoplastic pad placed on the sole gives protection from ground,” says Haydn. “If there is bruising, a form of packing sandwiched between pad and sole can help.
“If the horse has the potential to suffer from conditions directly associated with the coffin joint, a more appropriate approach would be to protect and support the joint using a soft silicon gel pack.”
According to Haydn, a practical farrier will gain a reasonable idea of what’s causing a horse to feel “footy” by looking at the hoof conformation.
“A flat sole is more susceptible to hard ground problems than a vaulted sole,” he says. “The horse might need a combination of a change of shoe profile and additional protection from modern materials such as packing and silicon.
“But be careful when putting pads on that you’re not just treating the symptoms rather than identifying the underlying cause,” he adds. “Open discussion between all parties — rider, vet and farrier — is essential.”
The importance of nutrition
Nutrition should be viewed as a long-term investment when it comes to hoof health, according to Richard Stephenson MRCVS.
“You cannot improve the quality of horn that already exists with feed supplements as horn is essentially a ‘dead’ tissue,” he says. “You can — potentially — influence the quality of new horn as it is produced at the coronary band, but you need to think in terms of using a feed supplement for 5-6 months minimum.
“Generally, hoof supplements should contain a concentrated source of the sulphur-rich amino acid methionine and nutrient methylsulfonylmethane [MSM] for keratin sulphate. The structural component in the hoof horn has a high sulphur content, so it is important to include these sulphur-rich nutrients for optimum keratinisation [horn development] and structural integrity of the hoof wall.
“Biotin is also essential for the production of keratin sulphate. Research has shown that a biotin deficiency can be a major cause of cracks and brittleness in the hoof wall. Zinc can also be beneficial.
“If you are buying a hoof supplement, check that it contains these essential elements.”
This vet feature was first published in Horse & Hound magazine (19 June, 2014)