Editor"s note: This article was written by Tom Fuhrmann, veterinarian and owner of DairyWorks, a management-consulting firm in Arizona.
Lameness is a general term that describes one of five specific causes for animals to have an abnormal walk or gait. Almost all lameness is due to foot rather than leg problems. So it is absolutely essential to pickup and inspect the lame foot to make the correct, specific diagnosis. A specific diagnosis is necessary because treatments differ greatly from one form of lameness to another. It is essential to your overall herd hoof health that lame cows be diagnosed early and treated correctly.
Lame cow issue 1: Foot Rot
Foot rot is a bacterial infection of the soft tissue of the foot causing swelling, pain and splitting of the skin between the two digits of the foot.
1. Temperature: 101.5 - 102.5 degrees F
- Other body organs: usually only 1 foot affected
- Obvious signs: lameness of one leg, swelling of the tissue around and above the foot, cracking or splitting of the tissue between the toes, soles of foot are normal
- Confirm diagnosis: lift and examine foot for classical clinical signs
- Differentiate from: sole abscess, foot/leg injury
PROGNOSIS: Excellent (>95 percent), chronic infection will develop if proper diagnosis and treatment is not made early; examine all lame cows immediately and start treatment as soon as possible.
Lame Cow Issue 2: Hairy Wart
Hairy wart is an infection of the skin usually at the heel of the foot. The skin infection is often a swollen red area with "hair-like" projections from it. The disease may cause severe pain and the animal can have a marked lameness.
- Temperature: normal
2. Other body organs: usually 1 foot affected
3. Obvious signs: lameness, foot has irritated skin at the heel, usually with "hair-like" projections from it
4. Confirm diagnosis: response to treatment is excellent
PROGNOSIS: Excellent (>99 percent)
Lame Cow Issue 3: Laminitis
Laminitis is lameness generally caused by acidosis. Rumenal acidosis causes the release of histamine which is carried in the blood to the feet. Histamine causes blood to "leak out" from the thousands of blood capillaries in the foot causing "pooling" of the blood spots. As these pools of blood decay, they change from blood cells to gas and liquid which produces pressure on all surrounding tissues deep within the foot. The pressure causes pain (lameness), tenderness and eventually the development of sterile pus which breaks out either at the top of the hoof or in the sole area. A nutritional feeding problem can cause subclinical lameness in a large percent of animals.
- Temperature: normal
2. Other body organs: more than 1 foot can be affected
3. Obvious signs: lameness of one or more feet, early stages; foot/feet are tender, later stages; black spots on sole, especially at "white line" area
4. Confirm diagnosis: lift and examine foot; pare away sole until black spots open to tract of pus, gas or dead tissue
5. Differentiate from; sole abscess
PROGNOSIS: Good (>90 percent) when treated early; fair (50:50) when treated after a lot of tissue damage occurs; poor (25:75) when secondary bacterial infection develops in affected area and foot becomes large and scarred.
Lame Cow Issue 4: Sole Abscess
Sole abscess is degeneration and decay of a spot of tissue deep in the sole of one digit of the foot. Sole abscess is usually not a bacterial infection; instead it is like a deep blister or bruise in the tissue which causes the development of liquid, sterile pus and gas. This fluid and gas causes pressure, pain and lameness.
- Temperature: normal
- Other body organs: usually only 1 foot
- Obvious signs: lameness of one leg, foot appears normal (no swelling of surrounding tissue), pare away one layer of sole to find a "black spot"; continue to pare away at the spot until the affected area becomes evident (liquid pus and gas oozes out)
- Confirm diagnosis: lift and examine foot; pare away sole until all black spots either disappear or lead to a tract of pus and gas
- Differentiate from: foot rot; foot/leg injury and laminitis
PROGNOSIS: Excellent (>95 percent), chronic infection will develop if the proper diagnosis and treatment is not made early; examine all lame cows immediately and start treatment as soon as possible.
Lame Cow Issue 5: Foot conformation/leg injury
Foot conformation/leg injury can be a variety of problems but these cause less than 5 percent of lameness in cattle. The cause of these lamenesses are either obvious (e.g. swelling of the leg, cuts or bruises) or are very subtle and diagnosed by ruling out the other 4 common causes of lameness.
The Importance of Training
Many times lame cow issues become chronic due to incorrect diagnosis and or delayed treatment. The success of your herd hoof health program depends upon how well trained your employees are to recognize symptoms and apply proper treatment protocols as determined by your veterinarian.