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

Abstract

OBJECTIVE

Interarcuate branch (IAB) is a vascular structure, particularly developed in C2-3 intervertebral space, forming a dorsal bridge that connects ventral venous plexi in the vertebral canal. While precisely described in the human, the precise anatomical features of IABs have not been reported in the veterinary literature. The purpose of this study is to describe the features and relations of IABs in the C2-3 vertebral canal.

ANIMALS

10 dogs were enrolled; 5 dogs for necropsy and 5 dogs for histology.

PROCEDURES

The ventral venous plexi in the cervical spine of 5 dogs were injected with latex and underwent vertebral canal dissection for visual assessment of the IAB. Two out of 5 dogs were injected with the addition of barium sulfate and underwent a CT scan. The C2-3 regions of 5 small-breed dogs were harvested for histological examinations.

RESULTS

IABs arose from the ventral venous plexus at the level of the intervertebral vein; they originated from 2 separate branches located caudally and cranially to the intervertebral foramen, forming a ventrodorsal triangle surrounding the spinal nerve root. No dorsal anastomosis was observed on the CT scan nor at dissection but were observed histologically. A cervical fibrous sheath was observed all around the vertebral canal.

CLINICAL RELEVANCE

IABs are voluminous venous structures at the C2-3 intervertebral space in dogs and found within a split of the cervical fibrous sheath, which is adherent to the interarcuate ligament and the ligamentum flavum. This anatomical description is paramount when planning an approach to the C2-3 intervertebral space.

Open access
in American Journal of Veterinary Research

Abstract

Objective—To determine whether conditions representing activities that are typical in the recreational use of horses, including transport to and from show grounds, stall confinement in unfamiliar surroundings, and light exercise, are associated with increased incidence of gastric ulcers in horses.

Design—Randomized controlled study.

Animals—20 client-owned horses.

Procedure—Horses had no gastric ulcers as determined by endoscopic examination on study day –1. Ten control horses were maintained on-site with no changes in management variables. Ten horses were transported via trailer for 4 hours on day 0 to another site, placed in individual stalls, fed twice daily, and exercised twice daily for 3 days. On day 4, they were transported back to the original site via trailer for 4 hours. On day 5, endoscopic examinations were performed on all horses to assess gastric mucosa status.

Results—Horses that were transported and housed off-site had a significantly higher incidence of hyperkeratosis and reddening of the gastric mucosa than control horses. Two control horses and 7 transported horses developed gastric ulcers by day 5. Ulcer scores of transported horses increased significantly from day –1, whereas ulcer scores in control horses did not change significantly from day –1.

Conclusions and Clinical Relevance—Activities that are typical in recreational use of horses were ulcerogenic, and ulcers in the gastric squamous mucosa can develop under these conditions within 5 days. ( J Am Vet Med Assoc 2005;227:775–777)

Full access
in Journal of the American Veterinary Medical Association

Summary

Milk samples were collected from all lactating cows on 60 dairies (mean number of cows/dairy, 584; range, 66 to 2,834) randomly selected from 701 California dairies enrolled in the Dairy Herd Improvement Association program. Samples were tested, by means of an elisa, for antibodies against Salmonella serogroup B, C1, and D1 antigens (somatic antigens 01, 4, 6, 7, 9, 12). Blood samples were collected from all cows with positive results and tested for serologic evidence of exposure to salmonellae. Samples for bacteriologic culture (pooled feces from 20 randomly selected calves, swabs of wet areas and feces from calf pens and dairy hospital pens, drag swab sample from wastewater lagoon, and samples of feed components) were also collected from all 60 dairies. Seven (11.7%) of the 60 dairies each had 1 sample that yielded Salmonella organisms (3 S typhimurium, 1 S dublin, 1 nonmotile Group D salmonella, 1 S derby, and 1 S oranienberg). Five of the Salmonella isolates came from the hospital pens and 2 came from calf pens. Thirty-three dairies did not vaccinate cattle against salmonellosis, and of these, 24 (72.7%) had ≥ 1 seropositive cow (titer ≥ 200), and 20 (61 %) had ≥1 persistently seropositive cow (titer for each of 2 blood samples collected ≥ 60 days apart was ≥ 200). Of the 27 dairies that did vaccinate cows against salmonellosis, 24 (89%) had ≥ 1 seropositive cow, and 21 (78%) had ≥ 1 persistently seropositive cow.

We concluded that studies that use of bacteriologic culture of fecal and environmental samples to determine the percentage of dairies with Salmonella-infected cows may underestimate the true percentage.

Free access
in Journal of the American Veterinary Medical Association

Summary

Environmental variables in 10 commercial turkey confinement buildings, representing 2 natural ventilation designs, were measured during summer and the following winter. Sliding doors spaced at intervals along the walls of 5 of the buildings provided about 35% opening, and continuous wall curtains provided 60 to 80% opening in the other 5 buildings. Environmental variables assessed included airspeed; temperature; relative humidity; gases; particle number, size, and mass per cubic meter of air; and colonies of bacteria, yeasts, and other fungi per cubic meter of air. Colonies of yeasts and other fungi were quantitated in feed and litter. For most of the variables evaluated, significant differences were not attributable to building ventilation design; however, in winter, the total mass of particulate matter per cubic meter of air was higher in the curtain-type houses, compared with sliding door-type houses. Ammonia concentration in the air of sliding door-type houses progressively increased during summer and winter sampling periods. A significant effect of building ventilation design on turkey performance was not detected when using mortality, average daily gain, feed conversion, condemnations at slaughter, or average individual bird weight as measures of production.

Free access
in American Journal of Veterinary Research

Summary

Distribution of blood flow among various respiratory muscles was examined in 8 healthy ponies during submaximal exercise lasting 30 minutes, using radionuclide labeled 15-μm diameter microspheres injected into the left ventricle. From the resting values (40 ± 2 beats/min; 37.3 ± 0.2 C), heart rate and pulmonary arterial blood temperature increased significantly at 5 (152 ± 8 beats/min; 38.6 ± 0.2 C), 15 (169 ± 6 beats/min; 39.8 ± 0.2 C), and 26 (186 ± 8 beats/min; 40.8 ± 0.2 C) minutes of exertion, and the ponies sweated profusely. Mean aortic pressure also increased progressively as exercise duration increased. Blood flow increased significantly with exercise in all respiratory muscles. Among inspiratory muscles, perfusion was greatest in the diaphragm and ventral serratus, compared with external intercostal, dorsal serratas, and scalenus muscles. Among expiratory muscles, blood flow in the internal abdominal oblique muscle was greatest, followed by that in internal intercostal and transverse throacic muscles, in which the flow values remained similar. The remaining 3 abdominal muscles had similar blood flow, but these values were less than that in the internal intercostal, transverse thoracic, and internal abdominal oblique muscles. Blood flow values for all inspiratory and expiratory muscles remained similar for the 5 and 15 minutes of exertion. However, at 26 minutes, blood flow had increased further in the diaphragm, external intercostal, internal intercostal, transverse thoracic, and the external abdominal oblique muscle as vascular resistance decreased. On the basis of our findings, all respiratory muscles were activated during submaximal exercise and their perfusion had marked heterogeneity. Also, blood flow in respiratory muscles was well maintained as exercise duration progressed; in fact, several muscles had a further increase in perfusion late during exercise.

Free access
in American Journal of Veterinary Research

for animals that appear healthy and clean to carry and shed the bacteria in their excreta, which can contaminate their fur, hair, feathers, scales, or skin. Salmonella spp can also be present in environments where animals or animal excreta, fur, hair

Full access
in Journal of the American Veterinary Medical Association

Objective—

To determine what risk factors, other than genetic predisposition, contribute to the incidence of feline infectious peritonitis (FIP) in private breeding catteries and animal shelters.

Design—

Cats from 7 catteries and a shelter were observed monthly for 1 year. At each visit, cats were examined, fecal samples were collected for determination of feline coronavirus shedding, and blood samples were collected for determination of coronavirus antibody titers. Diagnostic tests were performed on all cats that died of FIP.

Animals—

275 purebred or random-bred cats that were kept by private breeder-owners in homes.

Results—

24 cats died of FIP during the study. Development of FIP was not associated with cattery, mean cat number, mean age, sex, cattery median coronavirus antibody titer, husbandry and quarantine practices, caging and breeding practices, or prevalence of concurrent diseases. However, risk factors for FIP Included individual cat age, individual cat coronavirus titer, overall frequency of fecal coronavirus shedding, and the proportion of cats in the cattery that were chronic coronavirus shedders. Deaths from FIP were more frequent in fall and winter, and on the basis of analysis of cattery records, the number of deaths varied yearly. Epidemics (> 10% mortality rate) were reported at least once in 5 years in 4 catteries.

Clinical Implications—

Elimination of FIP from a cattery is only possible by total elimination of endemic feline enteric coronavirus (FECV) infection. The most important procedure to reduce FECV from catteries is elimination of chronic FECV shedders. (J Am Vet Med Assoc 1997;210:1313–1318)

Free access
in Journal of the American Veterinary Medical Association