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is ingested. 3 Pooling colostrum has benefits including being both labor reducing and an efficient way to feed a large number of calves. It is still a common practice on over 50% of large US dairies 4 but its effect on transfer of passive immunity

Open access
in Journal of the American Veterinary Medical Association

Summary

Osteochondral fragments from the axial proximoplantar/proximopalmar region of the proximal phalanx were removed from 38 joints in 30 horses. Ninety-three percent of the horses were Standardbreds, and 28 of the 30 had a low-grade lameness. All but 1 of the horses had hind limb involvement.

A total of 43 fragments were removed. Most (71%) of the fragments involved the medial aspect of the joint and had to be dissected from a covering of synovial tissue. Histologically, the circumference of most fragments consisted of a transition zone at the attachment of the joint capsule, a region of nonarticular, non-weight-bearing cartilage, a region where organized, dense connective tissue, presumably remnants of the short sesamoidean ligament were attached, and a region consisting of irregular truncated bony surfaces covered by mature fibrous tissue, which appeared to be the result of healing of a chronic fracture. There were several areas of degenerate hyaline cartilage, but no areas of normal hyaline cartilage or areas containing retained cartilage cores or other evidence of delayed endochondral ossification. Immunohistochemical staining of 4 segments from 1 horse revealed sensory substance P immunoreactive nerves in the fibrous tissue surrounding the bony fragments and within the central cancellous spaces. The histologic appearance suggests that these osteochondral fragments may be a result of fracture, rather than a manifestation of osteochondrosis.

Free access
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association

pathological diagnosis was made by the veterinary pathologist (Dr. Pool). ABBREVIATIONS FONFH Focal osteonecrosis of the femoral head LCPD Legg-Calvé-Perthes disease OCD Osteochondritis dissecans THR Total hip replacement Footnotes a

Full access
in Journal of the American Veterinary Medical Association

SUMMARY

The source of a previously described radiolucent crescent in the flexor cortex of the distal sesamoid (navicular) bone on the palmaro45°proximal-palmarodistal oblique (Pa45°Pr-PaDio) clinical radiographic projection was investigated in 48 forelimb navicular bones from 24 Thoroughbreds by use of high-detail radiography and x-ray computed tomography (ct). Twenty-five of these bones also were evaluated, using microradiography and histologic examinations. Of these 25 bones, 5 had been labeled in vivo with fluorochrome markers. Tetrachrome-stained 100-µm-thick nondecalcified sections of these 5 bones were examined, using epifluorescence microscopy.

A reinforcement line of compacted cancellous bone, parallel and several millimeters deep to the flexor cortex in the region of the flexor central eminence, was visualized by ct in 42 of 48 navicular bones and by microradiography in 23 of 25 navicular bones investigated. Variable degrees of compaction were observed in the cancellous bone between the flexor cortex and the reinforcement line. High-detail skyline radiographic projections and reconstructed ct images indicated a crescent-shaped lucency within the flexor central eminence of the flexor cortex in the bones in which the reinforcement line was identified, but the cancellous bone between the reinforcement line and the flexor cortex had not been compacted. The radiolucent crescent seen in the flexor central eminence of the navicular bone on the Pa45°Pr-PaDiO projection was not caused by the concave defect or synovial fossa of the flexor central eminence overlying the flexor cortex, as was described. The crescent-shaped lucency within the navicular bone flexor central eminence identified on clinical radiographs was associated with remodeling of cancellous bone within the medullary cavity of the navicular bone. It is hypothesized that remodeling of the cancellous bone is secondary to biomechanical stresses and strains placed on the navicular bone, although the clinical relevance of this finding was not determined during the study.

Free access
in American Journal of Veterinary Research

Summary

The forefimb superficial digital flexor (sdf) tendons of 6 Thoroughbreds were examined clinically and ultrasonographically during the first 4 months of race training. Sonograms were interpreted clinically and by use of computer-aided analysis. Tendon tissue from all horses was examined histologically at the end of the study.

Computer-aided analysis of sonograms of the sdf tendons revealed trends toward an increase in mean cross-sectional area and a decrease in mean echogenicity over time with training. An inverse relation was found between increase in cross-sectional area and decrease in mean echogenicity over time in training. Two of the trained horses developed clinical signs of mid sdf tendonitis. Ultrasonography revealed an increase in cross-sectional area and decrease in mean echogenicity of clinically affected areas of the sdf tendons of 1 horse, compared with changes observed prior to the onset of tendonitis (these changes were not statistically significant). Blood vessels and lymphatics supplying the clinically and ultrasonographically affected tendon sites were large and thick-walled. These changes were not observed in the tendons of the other horses at the end of the study.

The authors conclude that equine sdf tendons adapt to the early months of race training by increasing in size and decreasing in echogencity, as determined by ultrasonography.

Free access
in American Journal of Veterinary Research

pharmacokinetics of several drugs in veterinary species. 13–16 Naïve averaged and naïve pooled pharmacokinetic methods can also be used to assess a population of animals from which samples are infrequently obtained. Naïve averaged pharmacokinetic analysis

Full access
in Journal of the American Veterinary Medical Association

Heng HG , et al . Mandibular ossifying fibroma in a dog . Vet Pathol 2008 ; 45 : 203 – 206 . 10.1354/vp.45-2-203 5. Turrel JM Pool RR . Primary bone tumors in the cat: a retrospective study of 15 cats and a literature review . Vet

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective

To assess tendon morphology and non-reducible crosslink concentration, and associations of these findings with horse age and previously reported mechanical and ultrasonographic findings.

Sample Population

Superficial digital flexor tendon samples were obtained from 23 horses aged 2 to 23 years. The tendons had undergone ultrasonography and were submitted to biomechanical testing in the physiologic range prior to sample acquisition.

Procedure

Samples were sectioned in a transverse plane; then dorsal, palmar, central, lateral, and medial regions were evaluated for fascicle cross-sectional area (CSA), septal width, and vessel density (the product of vessel numbers and vessel CSA per field). Contiguous samples were analyzed for collagen crosslinking.

Results

Central fascicles were significantly larger than fascicles in other tendon regions. Fascicle CSA decreased significantly with increasing age. Because total tendon CSA is unrelated to increasing age, fascicle numbers appeared to increase with increasing age. Regional or age effects on septal width were not found. There was no age or regional effect on vessel numbers, density, or fractional area.

Fascicle CSA was positively correlated with total tendon CSA; fascicle CSA was negatively correlated with elastic modulus. Hydroxypiridinium concentration tended to increase with increasing horse age; this effect was associated with a positive correlation between hydroxypiridinium values and elastic modulus.

Conclusions

Equine superficial digital flexor tendon undergoes an increase in structural organization and an increase in nonreducible crosslinks with maturation and aging. These changes are associated with an increase in elastic modulus. (Am J Vet Res 1997; 58:425–430)

Free access
in American Journal of Veterinary Research