Strangulating obstruction caused by intestinal herniation through the proximal aspect of the cecocolic fold in 9 horses.

OBJECTIVE: To report the clinical and surgical findings and outcome for horses with strangulating obstruction caused by herniation through the proximal aspect of the cecocolic fold. STUDY DESIGN: Retrospective study. ANIMALS: Nine horses. METHODS: Medical records were reviewed for clinical signs, surgical findings and technique, and outcome. Cadaver ponies and necropsy specimens were also used to study the regional anatomy of the cecocolic fold. RESULTS: The ileum and distal jejunum were strangulated in 8 horses, whereas in 1 horse the small intestine and the left ascending colons were incarcerated in a rent in the cecocolic fold. Two horses were euthanatized at surgery, 6 horses had a small intestinal resection (mean length, 3 m; range, 1.5-6.4 m) and an end-to-side jejunocecostomy, and the entrapment was reduced without resection in the horse that had small intestine and ascending colon incarceration; cecocolic fold defects were not closed. One horse was euthanatized 36 hours after surgery because of endotoxemia. Six horses were discharged; 4 were available for long-term follow-up, of which 2 were euthanatized, and 2 were euthanatized 12 and 18 months after surgery because of colic signs. Variations in thickness of the cecocolic fold were observed in specimens obtained from necropsy of other horses and ponies. CONCLUSIONS: Reasons for this defect are unknown, although observed anatomic differences in cecocolic fold thickness may contribute to the development of defects. CLINICAL RELEVANCE: Reduction of the entrapped bowel is easiest when traction is placed on the bowel at a 90 degrees to the base of the cecum. Intestinal incarceration through rents within the proximal part of the cecocolic fold should be considered as a differential diagnosis for strangulating obstruction in horses.

Absence of an osseous patella and other observations in Macropodidae stifle.

The patella is a large sesamoid bone that typically develops in the tendon of insertion of the large extensor muscles of the stifle joint. Although present in almost all species of mammals and birds, it has been found to be absent in the red kangaroo and two wallaby species (family Macropodidae). In its place is a fibrocartilage pad, located in the tendon of the quadriceps femoris muscle. This structure is visible grossly, is palpable, and has the form normally expected of a bony patella. In addition, the femoral trochlea is shallow and asymmetric, and the lateral gastrocnemius sesamoid is unusually prominent. These and other related modifications in the area of the Macropodidae stifle are presented.

Clinical and xeroradiographic lymphangiography studies of acute and chronic Brugia pahangi infections in dogs.

Xeroradiographic lymphangiography was carried out at approximately monthly intervals on five dogs during the first 18 weeks following infection with 400 Brugia pahangi infective larvae in the left rear paw. Clinical signs, body temperatures and microfilaria counts were also monitored during this time. Similar observations were made on nine dogs with chronic infections (one to five years duration) of 200 infective larvae in unilateral inguinal sites. Standard thoracic radiography was conducted on all dogs. Surgical occlusion of the major afferent ducts to the popliteal lymph nodes of the infected and noninfected limbs of a chronically infected dog was performed to study oedema induction and resolution. This non-invasive lymphangiographic technique demonstrated marked differences in lymphatic changes among individual dogs. The severity of lymphatic pathology correlated with clinical signs of limb oedema and low microfilaria counts. Chronically infected dogs also demonstrated a variety of pathological manifestations: two dogs presented lymphatic cording and another showed transient lymphadenitis with fever and pulmonary arterial opacities. Surgical occlusion of major lymphatic ducts in an uninfected limb resulted in short-term oedema, while occlusion caused by B. pahangi in acutely infected dogs resulted in more persistent oedema. Surgical occlusion of a major duct in a chronically infected limb did not result in oedema. Xeroradiographic lymphangiography revealed a spectrum of lymphatic pathology in Brugia pahangi-infected dogs and demonstrated the value of this animal model for the study of the pathogenesis of chronic lymphatic filariasis.

Radiographic evaluation of appendicular skeletal maturation in the common marmoset (Callithrix jacchus).

The thoracic appendicular skeletal development of five common marmosets was monitored radiographically at weekly intervals from 1 day to 94 weeks of age and the times of appearance and fusion of 47 ossification centers were recorded. A range and average age for the appearance and fusion of each ossification center were calculated and compared to data available for the rhesus monkey and man.

Hepatozoon canis infection in dogs: clinical, radiographic, and hematologic findings.

Hepatozoon canis gametocytes were identified in circulating neutrophils of 3 dogs from different parts of Texas. Clinical signs included intermittent fever, stiffness, and inappetence. The dogs had marked neutrophilic leukocytosis (35,000--51,000/mm3). Parasitemia varied from less than 1% to 60% of the circulating neutrophils. Two of the dogs had periosteal new born reaction on the vertebrae, ilia, ribs, and bones of the limbs proximal to the carpus and tarsus. There was no evidence that specific drug therapy was of value, although use of corticosteroids, aspirin, and antimicrobial agents was accompanied by clinical improvement.