Footrot

lecture in epidemiology and infectious diseases of veterinary medicine.

1. Epidemiology & Infectious disease Foot Rot Lecturer Muna Tawfeeq Abd AL-Muthanna university /Iraq

2. Foot rot Definition An anaerobic infection of the soft tissues of the interdigital space causing lameness in cattle ,sheep and goat.

3. Foot rot In cattle: Synonym : Bovine Interdigital Necrobacillosis Etiology: Fusobacterium necrophorum Gram-negative bacteria is a non-spore forming obligate anaerobe and a normal inhabitant of the alimentary tract (particularly the rumen), the respiratory tract, and the genital tract. In sheep : Synonym : Ovine interdigital dermatitis' and is also called 'foot scald'. Etiology: bacteriodes nodosus in combination with Fusobacterium necrophorum

4. Normal foot after trimming Interdigital Foot rot

5. Epidemiology: The disease is common in all ages. The disease has a worldwide distribution usually the disease is sporadic and accounts for 5-15% of cases of lameness in dairy cattle. Transmission by discharges from the feet of infected animals

6. Environmental risk factors In many but not all regions, the incidence is much higher during wet, humid weather or when conditions are wet underfoot. Stony ground, lanes filled with sharp gravel and pasturing on coarse stubble also predispose to the condition . Host risk factors Cattle of all ages, including young calves ,may be affected but the disease is much more common in adults. The highest incidence occurs in cows in the first month of lactation

7. Economic impacts: In beef cattle at range the incidence is usually low but many cases may occur in pure-bred herds and in feedlot cattle. Lame cows will lie down for longer and eat less, have difficulty rising and are at greater risk for teat trampling and mastitis. Loss of production occurs and an occasional animal may suffer a serious involvement of the joint and other deep structures of the foot necessitating amputation of a digit. The disease is not fatal but some cases may have to be slaughtered because of joint involvement .

8. Clinical signs: lameness appears suddenly, usually in one limb only and may be accompanied with a fever(39-40 ℃) . There is temporary depression of milk yield in cows and affected bulls may show temporary infertility. The typical lesion occurs in the skin at the top of the interdigital cleft and takes the form of a fissure which is moist, red, swollen, and has a characteristic foul odor. Deeper tissues, such as bone, tendons, and joints, can also be affected in severe and advanced cases.

9. Pathogenesis : injury or constant wetting of the skin of the cleft allow to the organism invade the tissues leading to acute swelling and necrosis of the skin and SC tissues may spread to adjacent tendon sheaths, joint capsules and bone if treatment is delayed or ineffective.

10. Necropsy Findings Necropsy examinations are rarely carried out in cases of foot rot . Clinical Pathology Bacteriological examination is not usually necessary for diagnosis but direct smears of the lesion will usually reveal large numbers of a mixture of Fusobacterium and Bacteroides spp . Diagnosis The diagnosis is based on history and clinical findings of a moist, red fissure in the Interdigital space.

11. D.D in bovine: Traumatic Lesions Hoof Growth Abnormalities Laminitis Stable foot rot.

12. D.D in sheep: Foot abscess ( It usually affects only one foot, is not contagious and is characterized by extensive suppuration. The abscess occurs in a single claw on the foot and there is obvious local heat and pain on palpation). contagious ecthyma (proliferative lesion with scabs around mouth and coronet skin) Bluetongue ( coronitis severe erosions around mouth and nasal cavities, high fever) Foot and mouth disease (vesicles at coronary band and interdigital cleft and mouth, as outbreak infect all age). Ulcerative dermatitis (spread by physical contact with20% at mating,as granulating ulcer around mouth, genitalia, on coronet and digits). Strawberry foot rot Laminitis

13. Treatment Immediate treatment as soon as possible after the onset of swelling and lameness will give excellent recovery in 2-4 day. (systemic and locally). procaine penicillin G, 22 000 IU/kg BW.IM twice daily, or once daily for three consecutive days are effective . Sodium sulfadimidine (150-200 mg/kg BW) solution given by IV injection is highly effective.

14. antibiotic treatment for sheep can use any one of the following :   Single IM dose of 70 000 U/kg procaine penicillin and 70 mg/kg dihydrostreptomycin. Single IM dose of 10 mg/kg. Erythromycin. Single IM dose of 20 mg/kg Long-acting oxytetracycline.

15. local treatment by applying a local anesthetic (xylazine)then the foot is scrubbed, all necrotic tissue curetted away and apply Any suitable antibacterial spray.

16. it is recommended that the animal be kept standing on clean dry ground for a few hours after treatment Ointment preparation may be applied and secured with a bandage, which may be left on for several days .

17. control : Foot bathing with copper sulfate 5% in a doorway so that cattle have to walk through it twice daily . Employ pasture modifications if possible (e.g., rotate pastures more often, fill mud holes, remove sharp objects). sheep that are affected with severe lesion are treated with parenterally administered antibiotics or culled.

18. Thank you