Foul can affect both grazing and housed herds and Ms Pedersen advises keeping feet as clean as possible and maintaining walkways to minimise risk of infection.
While foul in the foot and corkscrew claw are not considered major causes of lameness among the UK's dairy herds, they can have serious impacts on cow health, particularly in the case of foul.
Sara Pedersen, veterinary consultant at Farm Dynamics, shares her advice on managing both conditions and best practice for treatment and prevention.
Foul in the foot
Unlike sole bruising, white line and sole ulcers, foul in the foot is caused by a bacterium affecting the soft tissues of the foot, rather than the hoof horn itself.
In most cases an injury or weakening of the skin in the interdigital space between claws allows bacteria, primarily fusobacterium necrophorum, to infect the skin and soft tissues between the claws.
Ms Pedersen says: "Foul develops when the bacteria have the opportunity to invade the soft tissue in between the claws, which could be through a foreign body puncturing the skin or wet conditions damaging the skin between the claws."
Seen in both housed and grazing herds and across all age groups, cases of foul are usually sporadic, but outbreaks can happen at specific times of year when weather conditions are favourable for both skin damage and bacteria establishment.
Ms Pedersen says more cases of foul are seen during wet, mild autumn weather when the cows are out and pastures are poached, or during the summer when the skin between the claws dries and cracks.
While the impacts of foul on dairy cattle are less studied than other lesions, Ms Pedersen says the condition is very acute and very severe.
She says: "It will make a cow go from sound to severely lame very quickly. She will be walking fine one day then the next day she is hanging back with a swollen foot and is not wanting to bear weight on it."
As a result, cattle tend to either lie down and not get up, or do not lie down at all, which combined with reduced feed intake often results in reduced milk production. In some cases, due to the bacterial infection, cows will also become unwell.
Some of the key signs to look out for when identifying foul include, acute onset lameness, swelling of the foot which also feels hot to touch, separation of the toes due to swelling and necrotic tissue, non-weight bearing lameness or standing on tip toes to relieve pressure on the foot.
READ NOW: Foot health: How to identify, treat and prevent white line disease
Early diagnosis and timely treatment are key to managing foul, says Ms Pedersen.
She says: "All of those principles about early detection and prompt effective treatment are especially applicable to foul. If you get it really early at the first sign of swelling, it is much more likely to respond quicker to treatment."
In all cases of foul, treatment should include injectable antibiotics and pain relief, says Ms Pedersen, who advises farmers to speak with their farm vet about which products are most suitable.
She also advises the interdigital space between the claws should be inspected for foreign bodies, cleaned and treated with a licensed topical antibiotic spray.
When looking to prevent foul, Ms Pedersen says the focus should be on reducing the infection pressure of bacteria through good slurry management, as well as reducing the risk of skin damage.
She says: "All of the same principles as digital dermatitis apply; it is about keeping the feet as clean as possible.
"Maintain tracks and gateways and make sure there is not too much poaching or too many little stones they could pick up between their feet. Foot bathing is really important as well."
READ NOW: Foot Health: Early treatment key to managing sole lesions
Corkscrew claw
Unlike foul, corkscrew claw impacts the anatomy of the foot meaning the condition cannot be treated, only managed.
Ms Pedersen says corkscrew claw happens when the horn in the claws does not grow straight, but twists as it grows, forming a distinctive corkscrew-like spiral.
Cases of corkscrew claw can vary between herds, with some herds seeing sporadic cases and others subject to high numbers of cases where specific risk factors are present.
The frequency of the condition is often dependent on the type of corkscrew claw at play, either classic or reverse corkscrew.
Ms Pedersen explains the outside wall of the hoof is twisted and placed in direct contact with the ground, while the inside wall rotates upwards in the interdigital cleft. The twisting results in a rotation of the toe, creating an inward and upward going spiral.
She says most farms will have had the odd case of classic corkscrew, which commonly affects the outside claw of the hind feet of older cattle.
She says: "It is often caused by factors such as age, genetics, poor housing or inappropriate trimming. But unless you have a specific bull in the herd that is causing a lot of issues, you may not see more than a few cases."
Reverse corkscrew effects the inside claws of the hind feet and is more commonly seen in heifers, says Ms Pedersen.
She says there has been an increase in cases in systems which have adopted best practice cow comfort principles from cow housing and applied it to heifers, such as sand bedding (especially recycled sand), good concrete grooving and head locking yokes.
She says: "The additional grip provided by good grooving and the sand creates a situation where heifers are more confident to push more and can put pressure on their feet as they feed.
"When they push more, they put more forces through the feet, and this leads to permanent changes as they continue to grow."
Dairy farms in America are also seeing cases of reverse corkscrew, with research showing farms which have reverted to not having head locking yolks, but are instead ensuring feed is always pushed up, so heifers are not reaching and pushing, have been able to stop cases of reverse corkscrew.
"Some of the work by the University of Wisconsin indicates that this is happening because of the management. This tells us that what we consider to be gold standard housing for cows may not be optimal for growing heifers."
Ms Pedersen says head locking yolks can still be used in heifer systems, but making sure they are an appropriate size and that heifers do not have to push for feed is important.
Once a case of corkscrew is established it cannot be reversed, says Ms Pedersen, therefore, the focus is on reducing ongoing deterioration and adaptation of trim techniques because of the change in anatomy.
Due to rotation of the bone within the claw, thin soles are more of a risk and so extra caution must be taken when trimming the sole.
"If you have got those abnormal forces through the feet while the heifer is growing, it leads to anatomical changes that we cannot correct through trimming," she says.
"We can manage it through trimming, but we need to be going a step back and thinking about when this is happening and how we alleviate it."
LISTEN NOW:
For herds experiencing high levels of corkscrew claw, the focus must be on removing the risk factors associated with their development, says Ms Pedersen.
Researchers in America suggest sand bedding increases hoof wear and thin soles, leading to inflammation of the pedal bone of the medial claws.
The claws are then susceptible to abnormal weight bearing forces during the period of skeletal development.
As a result, Ms Pedersen says a risk-based approach must be taken, with simple changes to feed barrier dimensions and space and design should be made initially to reduce forces through the feet, followed by assessing whether sand bedding should be avoided.
"Where changes have been made to remove these risk factors, corkscrews have been prevented," she says.
