Bovine Reproduction. Группа авторов
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Figure 16.19 Sole view of interdigital fibroma. Notice the ulceration that has occurred due to contact with the ground.
Sequestra should be surgically removed. Most often, these occur on the lateral aspect of the metatarsus and are directly related to trauma from kicking a hard object like a gate or post or entrapment of the limb within a confined space (Figure 16.20). On presentation, most cattle with a sequestrum will have an associated draining tract. Surgical removal can be performed under vascular anesthesia and sedation while the animal is restrained in lateral recumbency unless there is extensive bony proliferation that should also be removed, in which case general anesthesia should be considered. A surgical drain should always be incorporated in the closure, as there is virtually no way to close the entire dead space after removal of the sequestrum. The drain should be removed four to five days after surgery and recovery may take up to two weeks.
Figure 16.20 Sequestrum formation of the lateral cortex of MTIII in a yearling.
Sepsis of the superficial and/or deep digital flexor tendon is usually due to traumatic injury (laceration of the caudal pastern or heel bulb area) or due to extension of deep infection from a chronic hoof rot lesion. Parenteral antibiotics alone will not resolve this problem; surgical drainage is performed and a drain placed from the pastern, through the tendon sheath and above the dewclaw. Extensive and chronic sepsis may require complete resection of the superficial and deep flexor tendons, after which partial closure with packing and drain placement is a must. Active or passive lavage may be provided, with several bandage changes required to resolve the issue. The drain should be removed in five to seven days. Apply a hoof block to the non‐affected claw and cast the limb to the carpus or tarsus to alleviate pain and allow better ambulation. After four weeks the cast may be removed. Some deep digital flexor tendons may spontaneously rupture after treatment, which will cause the patient to walk on the heel bulb.
Proximal Limb
Lameness involving the femorotibial joint usually involves a traumatic episode such as a bullfight, breeding injury, or restraint accident. Suspected stifle injuries should be addressed immediately, and treatment should be aimed at decreasing inflammation and reducing the development of degenerative joint disease. Diagnostics often include observation of ambulation and weight bearing, amount of joint effusion present, joint laxity and the direction of laxity, radiographs, and ultrasound (which may not be possible in larger individuals) [13]. Arthrocentesis is used to rule out sepsis, and total cell count should be less than 2500 WBC/μl and protein less than 4.5 g/dl. Ideally, positive pressure joint lavage should be performed with a sterile isotonic fluid solution containing antibiotics and anti‐inflammatories [14]. Follow‐up therapies may include repeated lavage and regenerative medicine modalities such as plasma‐rich protein or stem cell therapy. Strict stall confinement is necessary for healing. Some injuries take up to six months to heal, and severe cranial cruciate or collateral ligament tears may require strict immobilization with a Thomas splint. These cases should be treated with long‐term non‐steroidal anti‐inflammatory drugs (NSAIDs). Of course, such injuries carry a very guarded prognosis when considering pasture soundness and return to breeding. If only the medial meniscus is involved, arthroscopic surgery may be of benefit in valuable individuals [15].
Lameness associated with the shoulder or elbow joint is often caused by trauma and can have a significant impact on ambulation. Non‐weight‐bearing lameness usually equates to serious injury such as a fractured scapula or fracture of the olecranon. A lesser degree of lameness may be observed with subchondral cysts or ligamentous injuries to supportive structures. Intra‐articular anesthetics may temporarily improve lameness but rarely resolve all of the pain during examination. Treatment of these joints is usually relegated to the use of intra‐articular injections unless surgical repair is financially feasible, for example compression plating of a fractured olecranon.
The carpus is probably the least affected large joint in beef cattle. Most lameness associated with this joint occurs in bucking bulls. Degenerative joint disease is observed in older bucking stock due to chronic hyperextension of the carpus when the bull “goes vertical.” This condition responds fairly well for a time to intra‐articular injections of anti‐inflammatories and the administration of NSAIDs.
Upward Fixation of the Patella
Upward fixation of the patella is a fairly easily diagnosed problem in the bovid. Cattle will have a hyperextended hindlimb (extension of tarsus with flexion of fetlock and all distal structure) that appears “locked” and causes the animal to drag the toe while walking. Those that have had the problem for a while will have worn down the toe on the affected limb. Occasionally an animal will exhibit the problem in both limbs, although one limb is often more severe. The condition most often affects females in the last trimester of pregnancy but is also observed in bucking bulls [16] (Figure 16.21).
Figure 16.21 Mature bred female experiencing upward fixation of the patella. Notice hyperextension and flexion of the fetlock with dragging of the toe.
This condition occurs when the patella is dislocated mediodorsally on the distal femoral trochlea and is treated with a medial patellar desmotomy. It is easier to identify the medial patellar tendon in the standing position. If there is a danger to the surgeon due to temperament, short‐acting anesthetics should be used. An appropriate anesthetic would be K‐stun (butorphanol, xylazine, ketamine) (Figure 16.22).
Figure 16.22 Excellent drug combo to facilitate brief examination of procedures in cattle.
The animal is restrained