Lameness in beef cattle can have serious economic consequences for producers. Lameness has several causes, which is why identifying the cause as soon as possible and applying the correct treatment is crucial.
According to Dr Dee Griffin of the Veterinary Medical Center at Texas A&M University, foot problems are responsible for as much as 5% of losses in feedlots. Moreover, foot problems represent approximately 70% of sales of non-performing cattle – only around 53% of the original purchase price is recovered in such instances.
A study conducted at five large feedlots in America showed that, although these animals were resold within roughly 85 days after arrival, they only gained 6kg during that time. Yet another study indicated that more than 15% of cull cows and 30% of cull bulls are sold due to lameness.
Causes of lameness
Claw problems represent approximately 70% of all problems associated with lameness. Other causes include injuries to the upper skeleton and muscles (15%), septic joints (12%) and lesions due to injections (3%).
The core aspect when it comes to treating lameness as well as preventing future problems, is accurate diagnosis, says Dr Griffin in an article on www.thebeefsite.com. Since most incidences of lameness involve the claws, it is important to lift the foot and thoroughly examine the claws. Never administer any form of treatment until a proper diagnosis has been made.
The greatest problems in feedlots are caused by mechanical injuries due to handling equipment, footrot and sole penetration which lead to abscesses. Footrot is also common in cull cows and bulls.
He points out that genetic and nutritional causes that lead to inflammation of the hoof wall, are also a common occurrence. Hoof sole inflammation associated with laminitis is quite prevalent in bulls.
Young cattle that ran on lush green grazing are particularly prone to toe abscesses. When the sole is penetrated, an abscess is formed. This leads to infection under the hoof wall because the sole is soft and easily worn down, especially in the toe area. It is usually the outer front toe that sustains the most damage, followed by the outer rear toe.
In the feedlot, calves that have been moved from high rainfall regions, or that ran on lush green grazing, are most susceptible to these problems. Furthermore, untamed cattle, abrasive surfaces and rough handling often exacerbate this condition.
Where toe abscesses become a recurring problem in a feedlot, it is necessary to examine the receiving area for cattle, says Dr Griffin. This area could be ‘too clean’. Soil and dry manure serve as a buffer for the animals’ claws and the condition tends to reappear once this ‘cushion’ is washed away by rain.
Identifying toe abscesses
Timeous identification of toe abscesses requires close observation. Cattle will take short strides during the early stages of abscess development and will possibly exhibit signs of slight discomfort. The foot will, however, not be swollen. Almost all animals treated at this stage will recover, but if the condition is allowed to worsen, the animal will become noticeably lame and may even keep the affected foot in the air. Slight swelling will be visible at the top of the claw.
Lift the foot and examine it thoroughly. When pressing your thumb on the side at the end of the toe, you will feel a soft spot. A crack may also be noticeable between the hoof wall and the sole.
The biggest noticeable difference between a toe abscess and footrot, is swelling between the claws. Swelling is indicative of footrot and requires a different form of treatment. Producers often confuse toe abscesses with footrot and will then incorrectly treat the animal for the latter. If toe abscesses are left untreated, there is a good chance the animal may lose the affected foot.
Treatment for toe abscesses requires just enough trimming at the end of the toe to relieve the pressure caused by the infection. If there is bleeding, you have trimmed too much. A long-acting tetracycline must also be administered. Antibiotics alone are not enough though; the hoof must be trimmed as well.
Although footrot is the main cause of lameness in cattle, its actual incidence is less than 10% of confirmed cases of lameness. Unfortunately, footrot and toe abscesses develop in a similar manner. Footrot is usually visible between the claws roughly a week or two after a mechanical injury has been sustained. Something as ordinary as a dry stick can lead to such an injury.
Fortunately, footrot is easy to treat, but it does require a proper diagnosis. Lift the foot and inspect the soft tissue between the claws. In cases of footrot, the tissue will be swollen and foul smelling. Treatment will require long-acting antibiotics – ointment is ineffective. As soon as you spot one case, be on the lookout for other animals with footrot as the condition tends to spread rapidly.
It is difficult to prevent footrot. Some producers include iodine in the feed, but the results are questionable. The levels of iodine approved in feed (10mg/animal/day) is not considered to be therapeutic. High levels of iodine can, over time, also interfere with certain immune functions.
There are indications that zinc methionine in the ration may be of value in preventing footrot. It can be used along with other additives such as antibiotics and ionophores.
Claw injuries are often the result of poorly designed or neglected handling facilities. The animal’s toe is trapped between the ground and the side of the crush. If the animal tries to step forward, it can lead to an injury.
While round instead of angular pipes at the bottom of the crush will reduce the chances of such injuries, there should ideally be no spaces between the floor and sides of the crush.
Equipment must be inspected before use. Loose metal rods can cause several injuries before being noticed. These types of mechanical injuries require immediate treatment and should not be left to heal on its own. Even a small injury can eventually cause a large and serious infection, with significant economic losses.
Between 10 and 15% of all cases of lameness are caused by septic joints. They usually fall into three categories, namely an infection that develops in the joint after a generalised infection, an injury to a joint, and an infection that develops in the joint following the unsuccessful treatment of a previous foot infection.
The most common joints involved are the front fetlock, the elbow and the hock. The stifle, hip and shoulder are rarely involved.
The three most common bacteria that cause septic joints are Haemophilus somnus, Pasteurella multocida and E. coli. Unfortunately, treatment rarely has a satisfactory outcome. Because the condition is extremely painful, it affects the amount of feed the animal ingests, which in turn affects its performance. It is often advised to rather cull the animal.
Muscle and injection damage
Severe muscle damage is common among new arrivals in a feedlot. These new animals must first rest for a period of six to 72 hours before being processed, so as to replenish the energy in their muscles. Muscle damage can be directly attributed to handling techniques. It is vital that only small groups are handled at any given time and that they are handled as gently as possible.
Injections can cause severe muscle damage. Swelling due to an injection can be extremely painful and can drastically reduce an animal’s feed intake. This has a direct effect on its daily weight gain. Most injection site damage can be prevented by carefully following the manufacturer’s instructions.
Subcutaneous administration of medication (if the manufacturer indicates it as an acceptable mode of administration) can drastically reduce muscle damage. In addition, never mix and apply different agents in the same syringe. Medication should never be mixed or accepted from anyone if different medications were mixed in the same bottle. – Izak Hofmeyr, Plaas Media
For more information and a list of references, contact the author at firstname.lastname@example.org. For hoof trimming and health services, visit Dairysmid Hoof Trimmers’ website at dairysmid.wixsite.com/dairysmid/