Prevent foot rot in your goats. (The goat barn).

Although more commonly thought of as affecting sheep, foot rot and related conditions can cause problems in the goat herd as well. Recognition along with proper treatment and management can help avoid serious economic loss.

Foot infections in goats are generally the result of the bacteria Fusobacterium necrophorum in combination with various other bacteria. Fusobacterium necrophorum is an anaerobic bacteria (one that survives in the absence of oxygen) that is part of the normal environmental flora of goats. Given the right conditions, these organisms invade the tissues of the hoof, usually gaining access through the interdigital tissues--the area between the toes.

Fusobacterium necrophorum in combination with the bacteria Cornybacterium pyogenes can result in a condition known as interdigital dermatitis or foot scald. Symptoms include lameness, and one or more feet may be affected. Foot scald commonly occurs during cold damp weather. Mechanical injury to the interdigital skin from stubble, burrs, accumulations of mud, etc. can also be a factor. The interdigital skin initially appears red and swollen and may later become grayish and necrotic, or dead looking. In advanced cases sloughing or erosion of the infected skin may be seen. In contrast to certain other hoof conditions there is no foul odor, drainage of pus, or separation of the hoof associated with food scald.

A severe complication of foot scald is a condition known as foot abscess. Foot abscess usually affects only one toe of one foot and is characterized by severe, acute lameness. It occurs when the foot scald infection extends into the deeper tissues and the joint. In this advanced infection pus may be expressed from between the toes or, in later stages, from above the coronet or upper edge of the hoof. Foot abscess can actually cause rupture of the ligaments of the foot leading to permanent disability. Unfortunately, the chances of complete recovery are poor, even with professional veterinary care.

Two other infections, benign and virulent foot rot, are caused by Fusobacterium necrophorum in combination with another anaerobic bacteria, Bacteroides nodosus. While Fusobacterium necrophorum is normally present in the goat's environment, Bacteroides nodosus can survive for only a few days on the ground without a host. In benign foot rot, a milder strain of Bacteroides nodosus is present. This infection occurs most often in warm, moist weather and symptoms are similar to those of foot scald. Benign foot rot is usually confined to the interdigital skin; however, unlike foot scald, a foul odor may be noted.

When the infection involves a more virulent or aggressive strain of Bacteroides nodosus, a condition known as virulent foot rot occurs affecting both the interdigital skin and the hoof matrix. In the presence of a warm, moist environment the skin between the toes becomes macerated or waterlogged, not unlike human skin that is immersed for a length of time in dish- or bath-water. Under these conditions Fusobacterium necrophorum invades initially, causing foot scald. If, at this point, Bacteroides nodosus invades the already infected skin, the condition progresses to virulent foot rot. This synergy or cooperation between bacteria is characteristic of virulent foot rot. Severe lameness affects one or more feet, and, in addition to the inflammation of the skin between the toes a foul-smelling, grayish-yellow pus may be noted. Body temperature may be elevated, lactation may cease and, eventually, the hoof may start to detach. Virulent foot is very contagious, and some animals may even become carriers.

Treatment for all the above infections starts with a thorough exam. Affected hooves should be trimmed and thoroughly scrubbed clean. Check for puncture wounds, foreign bodies, inflammation, drainage and swelling. Remember that lameness in goats can also be caused by conditions such as CAE or mastitis and by injury. Move the affected animal(s) to clean, dry bedding after walking them through a foot bath of 5-10% formaldehyde, 10% zinc sulfate, or 10-20% copper sulfate. Visibly infected hooves should be soaked in the foot bath solution for at least 10 minutes. Some sources recommend soaking up to one hour. A little laundry detergent may be added to the soaking solution to increase penetration of the medication. Injectable antibiotics may shorten the course of the infection. The Merck Veterinary Manual recommends either oxytetracycline (5-10mg per kg every 24 hours) or benzathine penicillin G (10,000-40,000 IU per kg every 48 to 72 hours.) Check the product insert for further, information and remember withdrawal times for lactating animals. Inexperienced goat owners should consult their veterinarian for specific treatment recommendations. A vaccine--Footvax--is available; however, it won't provide complete control and should be used in conjunction with other measures. Recheck all treated animals in one to two weeks and repeat the foot bath/soak, then recheck every two weeks for two months.

Good management practices can help prevent foot infections in goats. As these infections tend to occur in wet environments, provide for good drainage in pastures and lots. If feasible, rotating pastures and lots can also help, as ground is considered decontaminated after three to four weeks. Quarantine all new animals for one month, after careful hoof trimming and a preventative foot bath. Provide regular hoof care and trimming for all animals in the herd. Finally, and probably most importantly, good management hinges on careful daily observation of your herd to identify any potential problems before they have a chance to escalate.

JUDY BOWMAN
TABLETOP HOMESTEAD
RR1, Box 10360
FOSTER, OK 73434