[{"Title":"Infectious Hoof Lesions","UniqueID":"v80036282_pt","Index":1.0,"Summary":"

This photograph shows a chronically recurring, proliferative, painful digital dermatitis lesion in the interdigital cleft of the plantar surface of a cow’s foot.

","HeadType":"E_Head","SchemeItemProp":"","Children":[{"Title":"Digital Dermatitis","UniqueID":"v80036287_pt","Index":1.0,"Summary":"

This photograph shows a chronically recurring, proliferative, painful digital dermatitis lesion in the interdigital cleft of the plantar surface of a cow’s foot.

","HeadType":"F_Head","SchemeItemProp":"","Children":[{"Title":"Pathogenesis","UniqueID":"v80036294_pt","Index":1.0,"Summary":"

When the skin of a cow's foot are damaged by mechanical irritation and maceration by water and chemicals, a synergistic group of bacteria can invade the compromised skin barrier and create acute inflammation and infection of the dermis and epidermis. These bacteria are common in the environment and normally live in the rumen. The fact that digital dermatitis is not present on all farms suggests that more virulent strains of these bacteria are present on some farms. Treponema spp are a necessary component of this group of bacteria for generating disease. Treponema spp are gram-negative spirochetes that are microaerophilic and can encyst to protect themselves. As the bacteria invade the epidermis and damage the different layers, the body responds with a local inflammatory process that can result in hyperkeratosis and proliferative lesions.

","HeadType":"G_Head","SchemeItemProp":"","Children":[]},{"Title":"Diagnosis","UniqueID":"v80036297_pt","Index":2.0,"Summary":"

Digital dermatitis presents in a variety of stages ranging from painful, bright red, ulcerated skin lesions to less painful, gray-black, circular, granulomatous skin lesions. Edges can have a white margin and/or “hairs” protruding from them. Lesions are clearly demarcated and are typically located in the interdigital cleft; they can also occur at other locations, such as in the interdigital space or at the front of the foot. Severe lesions can become either proliferative with filamentous projections or hyperkeratotic. For practical purposes, it is useful to classify lesions as active (painful and ulcerative lesions > 2 cm) or chronic (gray-black hyperkeratotic lesions without painful ulcerative lesions > 2 cm).

","HeadType":"G_Head","SchemeItemProp":"","Children":[]},{"Title":"Prevention","UniqueID":"v80036300_pt","Index":3.0,"Summary":"

The main focus to prevent digital dermatitis is hygiene. Providing a clean environment without wet and/or abrasive walking surfaces decreases the chances of weakening the skin barrier. Foot baths are a preventive measure that should be used regularly, at whatever frequency is necessary to minimize the occurrence of active painful lesions. Foot baths are typically filled with disinfectant solutions such as copper sulfate or formalin and should be at least 10 feet (3 m) long to achieve a minimum of two immersions per rear foot. Other preventive measures include not allowing infected animals to enter the herd and ensuring that replacement animals are managed to prevent new infections.

","HeadType":"G_Head","SchemeItemProp":"itemprop=\"primaryPrevention\" itemscope itemtype=\"http://schema.org/MedicalTherapy\"","Children":[]},{"Title":"Treatment","UniqueID":"v80036304_pt","Index":4.0,"Summary":"

The number of licensed products that exist to treat digital dermatitis is sparse and varies from place to place. Treatment typically consists of applying topical tetracycline-based antimicrobials to active lesions by using a wrap or a paste. The microaerophilic nature of the bacteria makes wraps unnecessary; if they are used, however, they should be removed within 24 hours of application. Other topical agents that contain heavy metals such as copper are also often used in the field. The role of topical treatment is to treat active lesions, hastening their transition to a chronic stage, and to decrease pain. Once the lesion is in a chronic stage, it is the role of the foot bath to prevent recurrence.

","HeadType":"G_Head","SchemeItemProp":"itemprop=\"possibleTreatment\" itemscope itemtype=\"http://schema.org/MedicalTherapy\"","Children":[]}]},{"Title":"Foot Rot","UniqueID":"v80036307_pt","Index":2.0,"Summary":"

This photograph shows a chronically recurring, proliferative, painful digital dermatitis lesion in the interdigital cleft of the plantar surface of a cow’s foot.

","HeadType":"F_Head","SchemeItemProp":"","Children":[{"Title":"Pathogenesis","UniqueID":"v80036316_pt","Index":1.0,"Summary":"

The most common bacteria associated with foot rot are Fusobacterium necrophorum, Dichelobacter nodosus, Trueperella pyogenes, Porphyromonas levii, and Prevotella intermedia. They are all gram-negative anaerobes that are present in the GI system of cattle and, as a result, are also found in the animal’s environment. These bacteria invade through a breach in the interdigital skin and then work synergistically to cause inflammation and necrosis of the soft tissues in the lower leg.

","HeadType":"G_Head","SchemeItemProp":"","Children":[]},{"Title":"Diagnosis","UniqueID":"v80036324_pt","Index":2.0,"Summary":"

Foot rot is recognized by the sudden onset of lameness, accompanied by symmetrical swelling of the lower leg above the hoof. It can present in an outbreak at herd level as a result of the sudden exposure to a risk factor for the disease. Depending on the stage of the disease, the interdigital skin splits open, and a foul-smelling discharge is noticeable. In more severe cases, loose pieces of necrotic tissue can be easily removed from the interdigital space.

","HeadType":"G_Head","SchemeItemProp":"","Children":[]},{"Title":"Prevention","UniqueID":"v80036328_pt","Index":3.0,"Summary":"

The key focus to prevent foot rot is to prevent skin damage, thereby removing the opportunity for bacterial infection. Skin damage, typically of mechanical origin, results from contact with rocks, sharp edges, cables, and other hazardous objects or protrusions in the animal's housing environment. Skin damage can also result from chronic wetting of the foot in muddy or wet and dirty environments. On dairy farms, the use of foot baths with a range of disinfectants is an aid to clean and disinfect the interdigital skin. Currently, no pharmaceutical products are labeled with a claim to prevent foot rot.

Foot rot should be treated with systemic antimicrobials according to label directions. There is typically no need to remove necrotic tissue or apply bandages. Treated animals should visually improve within 2–3 days. If animals do not respond, the diagnosis should be reevaluated. In severe cases, the infection can extend to tendons and joints, resulting in very severe lameness that is unresponsive to regular systemic antimicrobial treatment.

","HeadType":"G_Head","SchemeItemProp":"itemprop=\"possibleTreatment\" itemscope itemtype=\"http://schema.org/MedicalTherapy\"","Children":[]}]},{"Title":"Heel Horn Erosion and Interdigital Dermatitis","UniqueID":"v80036335_pt","Index":3.0,"Summary":"

This photograph shows a chronically recurring, proliferative, painful digital dermatitis lesion in the interdigital cleft of the plantar surface of a cow’s foot.

","HeadType":"F_Head","SchemeItemProp":"","Children":[{"Title":"Pathogenesis","UniqueID":"v80036344_pt","Index":1.0,"Summary":"

The most common bacterium associated with heel horn erosion and interdigital dermatitis is Dichelobacter nodosus, a gram-negative, anaerobic, commensal, and opportunistic bacterium. Typically, the bacteria invade skin and horn that have been damaged by wet and dirty environments. The bacteria then create a cycle of further damage that is due to their virulence factors and the body’s response of excessive horn growth.

","HeadType":"G_Head","SchemeItemProp":"","Children":[]},{"Title":"Diagnosis","UniqueID":"v80036348_pt","Index":2.0,"Summary":"

Heel horn erosion and interdigital dermatitis are common findings at routine hoof trimmings. Heel horn erosion typically presents as superficial damage to the non-weight-bearing heel horn that causes undermining and grooves in a V-like pattern on both heels. Interdigital dermatitis presents as pale and damaged skin in the interdigital space. Typically, lameness results only if the erosion extends to the level of the corium.

","HeadType":"G_Head","SchemeItemProp":"","Children":[]},{"Title":"Prevention","UniqueID":"v80036351_pt","Index":3.0,"Summary":"

Prevention of heel horn erosion should focus on avoiding prolonged exposure to wet and dirty environments. As with other infectious hoof lesions, using foot baths regularly and appropriately to clean and disinfect hooves is a preventive measure in housed dairy cows.

Heel horn erosion and interdigital dermatitis are treated during the trimming process mainly by the removal of loose horn from the non-weight-bearing surface of the heel. Anaerobic pockets in the grooves of the heel horn are removed at the same time, eliminating the environment that supports the growth of the causative bacteria.

","HeadType":"G_Head","SchemeItemProp":"itemprop=\"possibleTreatment\" itemscope itemtype=\"http://schema.org/MedicalTherapy\"","Children":[]}]}]},{"Title":"Noninfectious Hoof Lesions","UniqueID":"v80036358_pt","Index":2.0,"Summary":"","HeadType":"E_Head","SchemeItemProp":"","Children":[]},{"Title":"Sole Hemorrhages","UniqueID":"v80036362_pt","Index":3.0,"Summary":"

Sole hemorrhages typically occur beneath the flexor tuberosity of the third phalanx (P3) or along the white line; they can also occur on any part of the weight-bearing surface of the hoof. The lameness associated with a sole hemorrhage varies in relation to the time since onset and the size of the hemorrhage. Sole hemorrhages should be thought of as precursors to more severe hoof lesions, such as sole ulcers (below).

","HeadType":"F_Head","SchemeItemProp":"","Children":[{"Title":"Pathogenesis","UniqueID":"v80036369_pt","Index":1.0,"Summary":"

","HeadType":"G_Head","SchemeItemProp":"","Children":[]},{"Title":"Diagnosis","UniqueID":"v80036373_pt","Index":2.0,"Summary":"

","HeadType":"G_Head","SchemeItemProp":"","Children":[]},{"Title":"Prevention","UniqueID":"v80036378_pt","Index":3.0,"Summary":"

","HeadType":"G_Head","SchemeItemProp":"","Children":[]},{"Title":"Treatment","UniqueID":"v80036381_pt","Index":4.0,"Summary":"

","HeadType":"G_Head","SchemeItemProp":"","Children":[]}]},{"Title":"Sole Ulcers","UniqueID":"v80036384_pt","Index":4.0,"Summary":"

Sole ulcers are damaged or penetrated areas of the sole horn due to increased pressure and repeated compression of the corium. They commonly occur beneath the flexor tuberosity of P3. They are associated with varying amounts of pain and resulting changes in weight bearing.

","HeadType":"F_Head","SchemeItemProp":"","Children":[{"Title":"Pathogenesis","UniqueID":"v80036390_pt","Index":1.0,"Summary":"

","HeadType":"G_Head","SchemeItemProp":"","Children":[]},{"Title":"Diagnosis","UniqueID":"v80036394_pt","Index":2.0,"Summary":"

","HeadType":"G_Head","SchemeItemProp":"","Children":[]},{"Title":"Prevention","UniqueID":"v80036398_pt","Index":3.0,"Summary":"

","HeadType":"G_Head","SchemeItemProp":"","Children":[]},{"Title":"Treatment","UniqueID":"v80036402_pt","Index":4.0,"Summary":"

","HeadType":"G_Head","SchemeItemProp":"","Children":[]}]},{"Title":"White Line Disease","UniqueID":"v80036407_pt","Index":5.0,"Summary":"