A Case of Ovarian Dysplasia and a Vaginal Fibroleiomyoma in a Young Golden Retriever

This case demonstrates a unique ovarian congenital anomaly that likely contributed to the development of a rare fibroleiomyoma in the cranial vagina of a young bitch. A 13 month old intact female Golden Retriever presented to the veterinary teaching hospital for urinary incontinence, hematuria, and persistent vaginal discharge. Physical examination revealed a mucopurulent serosanguinous malodorous vulvar discharge, and after further diagnostics was reclassified as persistent estrus. Abdominal palpation and ultrasound revealed uterine thickening and poorly visualized ovaries. The reproductive tract was removed during an ovariohysterectomy, revealing small ovaries and a white anterior vaginal mass. Histopathology revealed dysplastic ovaries with hyperplastic granulosa cells and a benign vaginal fibroleiomyoma. These morphologic changes are consistent with elevated estrogen levels. It was thus concluded that her persistent estrus and the fibroleiomyoma were both secondary to persistent estrogen production by the hyperplastic granulosa cells.

Hematological and histological changes from ingestion of Deepwater Horizon crude oil in zebra finches (Taeniopygia guttata)

Exposure to crude oil during spill events causes a variety of pathologic effects in birds, including oxidative injury to erythrocytes, which is characterized in some species by the formation of Heinz bodies and subsequent anemia. However, not all species appear to develop Heinz bodies or anemia when exposed to oil, and there are limited controlled experiments that use both light and electron microscopy to evaluate structural changes within erythrocytes following oil exposure. In this study, we orally dosed zebra finches (Taeniopygia guttata) with 3.3 or 10 mL/kg of artificially weathered Deepwater Horizon crude oil or 10 mL/kg of peanut oil (vehicle control) daily for 15 days. We found that birds receiving the highest dosage experienced a significant increase in reticulocyte percentage, mean corpuscular hemoglobin concentration, and liver mass, as well as inflammation of the gastrointestinal tract and lymphocyte proliferation in the spleen. However, we found no evidence of Heinz body formation based on both light and transmission electron microscopy. Although there was a tendency for packed cell volume and hemoglobin to decrease in birds from the high dose group compared to control and low dose groups, the changes were not statistically significant. Our results indicate that additional experimental dosing studies are needed to understand factors (e.g., dose- and species-specific sensitivity) and confounding variables (e.g., dispersants) that contribute to the presence and severity of anemia resulting from oil exposure in birds.

Fibrous osteodystrophy in a dromedary camel

A 6-y-old female dromedary camel (Camelus dromedarius L.) was presented for assessment of firm, bilateral swellings rostral and ventral to the eyes. Serum biochemistry revealed hyperglycemia (28.5 mmol/L), hypocalcemia (1.27 mmol/L), hyperphosphatemia (3.39 mmol/L), hypoproteinemia (total protein 50 g/L), and hypoalbuminemia (20 g/L). Based on the poor prognosis associated with the presumptive diagnosis of fibrous osteodystrophy, the camel was euthanized. Gross postmortem findings revealed expanded fibrous tissue replacing the maxilla and mandible, and bilaterally prominent parathyroid glands. Histology of the maxilla revealed proliferative loose fibrous tissue with widely scattered, regularly spaced, small spicules of mineralized bone. The parathyroid glands were prominent bilaterally; the internal and external parathyroid glands were composed of plump cells with abundant pale basophilic cytoplasm and open nuclei. The pathologic findings were consistent with the antemortem diagnosis of fibrous osteodystrophy. The camel's diet, which was not specifically balanced for a camel, included grass hay, sweet feed, and alfalfa pellets. The camel's caregivers reported feeding her treats of cookies. A feed analysis was not available. The biochemistry abnormalities and clinical and postmortem findings, along with a diet that was not balanced for a camel, are consistent with a diagnosis of nutritional secondary hyperparathyroidism.

CT and gross pathology are comparable methods for detecting some degenerative sacroiliac joint lesions in dogs

Degenerative sacroiliac joint disease is a cause of lumbosacral pain in dogs; however, published information on cross-sectional imaging characteristics is limited. Objectives of this retrospective, secondary analysis, methods-comparison study were to test hypotheses that CT lesions reported in humans with degenerative sacroiliac joint disease are also present in dogs, and that CT is comparable to gross pathology for detecting these lesions. Matched CT and gross pathology slice images of 30 sacroiliac joints were retrieved from a previous prospective, canine cadaver study. A veterinary radiologist interpreted randomized CT images for each joint based on previously published CT characteristics of lesions in humans with degenerative sacroiliac joint disease. A veterinary pathologist independently interpreted randomized gross pathology images using the same criteria. All joints had at least one CT lesion consistent with degenerative sacroiliac joint disease. A new CT lesion was also identified and termed "subarticular cleft." The CT and gross pathology methods agreed for detecting joints with subchondral sclerosis, subchondral erosion, and intra-articular ankylosis lesions (P > .05, McNemar's test), but disagreed for detection of joints with subchondral cyst, para-articular ankylosis, and subarticular cleft lesions (P ≤ .05). Using gross pathology as the reference standard, CT had 100% sensitivity for detection of subarticular cleft and subchondral cyst lesions, with 56% and 22% specificity, respectively. Para-articular ankylosis lesions were detected by CT but not by gross pathology. Findings supported the hypothesis that CT lesions reported in humans with degenerative sacroiliac joint disease are also present in dogs, and partially supported the hypothesis that CT is comparable to gross pathology for detecting joints with these lesions.

A Case of Segmental Aplasia of the Uterus, Cervix, and Cranial Vagina in a Cat

This case documents a rare set of congenital anomalies that resulted in an atypical cystic lesion in the cranial vagina of a queen. A discrete cystic lesion was identified in an 8 year old intact female domestic shorthair cat presenting for routine ovariohysterectomy. Morphological, radiographic, and histopathological findings were consistent with segmental aplasia of the uterus, cervix, and vagina resulting in a blind dilation of the cranial vagina. Segmental vaginal aplasia in combination with the failed canalization of the cervix resulted in a blind portion of the cranial vagina, in which normal secretions collected and became inspissated. This formed a discrete cystic structure. This case represents a novel combination and clinical presentation of segmental aplasia in the cat, involving both the uterus and cranial vagina. Ovariohysterectomy was performed for sterilization and a partial vaginectomy was performed to remove the cystic lesion in its entirety.

Conservation of rare and local breeds of livestock

The genetic diversity of domesticated species is contained within breeds, with the result that conserving breeds conserves this diversity. Breeds are predictable genetic resources that allow a match of animals with different environments and production goals. Breeds were developed through a process involving foundation, isolation and selection. Breed types that qualify as genetic resources include 'landraces' (local breeds), standardised breeds, commercial production breeds and feral livestock that have returned to a free-living state. Currently, breeds of all classes are threatened with extinction. The reasons for breed conservation include maintaining breed diversity for future needs, cultural connections between people and breeds, and material for scientific investigation. Several breeds have undergone genetic adaptations that make them uniquely suited to specific challenging environments. Conservation depends upon discovering these genetic resources, securing them with a good genetic structure, and subsequently sustaining them for long-term survival with demand for the breed and its products.

The legacy of Columbus in American horse populations assessed by microsatellite markers

Criollo horse populations descend from horses brought from the Iberian Peninsula over the period of colonization (15th to 17th century). They are spread throughout the Americas and have potentially undergone genetic hybridization with other breeds in the recent past. In this study, 25 autosomal microsatellites were genotyped in 50 horse breeds representing Criollo populations from 12 American countries (27 breeds), breeds from the Iberian Peninsula (19), one breed each from France and Morocco and two cosmopolitan horse breeds (Thoroughbred and Arabian). The genetic relationships among breeds identified five clusters: Celtic; Iberian; North American with Thoroughbred influence; most Colombian breeds; and nearly all other Criollo breeds. The group of "all other Criollo breeds" had the closest genetic relationship with breeds originating from the Iberian Peninsula, specifically with the Celtic group. For the whole set of Criollo breeds analysed, the estimated genetic contribution from other breeds was approximately 50%, 30% and 20% for the Celtic, Iberian and Arab-Thoroughbred groups, respectively. The spatial distribution of genetic diversity indicates that hotspots of genetic diversity are observed in populations from Colombia, Ecuador, Brazil, Paraguay and western United States, possibly indicating points of arrival and dispersion of Criollo horses in the American continent. These results indicate that Criollo breeds share a common ancestry, but that each breed has its own identity.

Leukocyte adhesion deficiency type I in a mixed-breed dog

A 6-month-old, neutered male, mixed-breed dog was examined for a 2-month persistent fever, nonhealing dermal metacarpal area wound, and leukocytosis (47.0-198.0 × 10(3)/μl). Serum chemistry findings included hypoalbuminemia, hyperglobulinemia, hyperphosphatemia, and hyperphosphatasemia. Complete blood cell count results revealed a moderate microcytic, hypochromic nonregenerative anemia with a profound leukocytosis (198.5 × 10(3)/μl), characterized by neutrophilia with toxicity and hypersegmentation, and significant band cells. Tick-borne disease titers (genera Anaplasma, Ehrlichia, and Borrelia) were negative, as were polymerase chain reaction for other infectious agents (genera Hepatozoon, Mycobacterium, Mycoplasma; and Canine distemper virus). No agents were identified in a deep dermal biopsy (conventional and special histochemical stains) of the chronic draining, metacarpal region lesion. Cytology of the draining tract revealed numerous mixed bacteria and a surprising lack of neutrophils. Chronic occult blood loss with iron deficiency was considered a possible cause of the anemia. Differentials for the leukon were chronic established inflammation (occult infectious agent), chronic neutrophilic leukemia, paraneoplastic leukocytosis (neoplastic source of granulocyte colony-stimulating factor [CSF] or granulocyte-macrophage CSF), and leukocyte adhesion deficiency (LAD). The possibility of a LAD disorder was further investigated because of the noted hypersegmented neutrophils, absence of neutrophils in the cytology sample, the animal's young age, and persistence of clinical and laboratory signs. Flow cytometry of blood neutrophils showed a 60% reduction in surface expression of the β2-integrin (CD18) subunit, whereas neutrophil function tests (oxidative burst and phagocytosis) were normal. Genetic testing revealed a homozygous missense mutation in the β2-integrin subunit gene, previously recognized only in purebred Irish Setters, leading to a diagnosis of LAD type 1 disorder in this mixed-breed dog.

Serological evidence for a hepatitis e virus-related agent in goats in the United States

Hepatitis E virus (HEV) causes an important public health disease in many developing countries and is also endemic in some industrialized countries. In addition to humans, strains of HEV have been genetically identified from pig, chicken, rat, mongoose, deer, rabbit and fish. While the genotypes 1 and 2 HEV are restricted to humans, the genotypes 3 and 4 HEV are zoonotic and infect humans and other animal species. As a part of our ongoing efforts to search for potential animal reservoirs for HEV, we tested goats from Virginia for evidence of HEV infection and showed that 16% (13/80) of goat sera from Virginia herds were positive for IgG anti-HEV. Importantly, we demonstrated that neutralizing antibodies to HEV were present in selected IgG anti-HEV positive goat sera. Subsequently, in an attempt to genetically identify the HEV-related agent from goats, we conducted a prospective study in a closed goat herd with known anti-HEV seropositivity and monitored a total of 11 kids from the time of birth until 14 weeks of age for evidence of HEV infection. Seroconversion to IgG anti-HEV was detected in seven of the 11 kids, although repeated attempts to detect HEV RNA by a broad-spectrum nested RT-PCR from the faecal and serum samples of the goats that had seroconverted were unsuccessful. In addition, we also attempted to experimentally infect laboratory goats with three well-characterized mammalian strains of HEV but with no success. The results indicate that a HEV-related agent is circulating and maintained in the goat population in Virginia and that the goat HEV is likely genetically very divergent from the known HEV strains.

Clinicopathologic features of intracranial central neurocytomas in 2 dogs

BACKGROUND

In humans, central neurocytomas are rare and typically benign intracranial tumors found within the lateral ventricles, although extraventricular variants have been reported. Intracranial central neurocytomas have not been previously recognized in domestic animals.

OBJECTIVES

To describe the clinicopathologic features of canine intracranial central neurocytomas.

ANIMALS

Two dogs with spontaneous intracranial and intraventricular neoplasms.

RESULTS

Both dogs experienced seizures, rapid neurological deterioration, and death from tumor-associated complications within 5 days of the onset of clinical signs, and had neoplastic masses within the lateral ventricles. A brain MRI was performed in 1 dog, which revealed a T1-isointense, heterogeneously T2 and FLAIR hyperintense, and markedly and heterogeneously contrast-enhancing mass lesions within both lateral ventricles. Histologically, the neoplasms resembled oligodendrogliomas. The diagnosis of central neurocytoma was supported by documenting expression of multiple neuronal markers, including neuron-specific enolase, synaptophysin, neural-cell adhesion molecule, and neuronal nuclear antigen within the tumors, and ultrastructural evidence of neuronal differentiation of neoplastic cells.

CONCLUSIONS AND CLINICAL IMPORTANCE

Central neurocytoma should be a differential diagnosis for dogs with intraventricular brain masses. Morphologic differentiation of central neurocytoma from other intraventricular neoplasms, such as ependymoma or oligdendroglioma, can be difficult, and definitive diagnosis often requires immunohistochemical or ultrastructural confirmation of the neural origin of the neoplasm.

A single mid-gestation exposure to TCDD yields a postnatal autoimmune signature, differing by sex, in early geriatric C57BL/6 mice

We recently observed an autoimmune profile in 24-week-old C57BL/6 mice that received a 2.5 or 5.0μg/kg mid-gestation dose of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) (Mustafa et al., 2008). The clinical signs were consistent with a lupus-like syndrome and included: increased autoantibody levels, renal IgG and C3 immune complex deposition with associated inflammation, and increased peripheral Vβ(+) T cells. No studies currently exist following the progression of such disease into middle or advanced ages, when human autoimmune diseases may manifest. Therefore in the present study, littermates of mice from the previous 24 week prenatal TCDD study were allowed to age to 48 weeks, considered early geriatric in mice. Similarities and differences in the disease profile based on age and sex were observed. Peripheral autoreactive Vβ(+) T cells were increased in both sexes at 48 weeks, in contrast to males only at 24 weeks. Activated T cells from 48-week-old prenatal TCDD females over-produced the pro-inflammatory cytokine IFN-γ while males over-produced IL-10, effects again not seen at 24 weeks. Splenic transitional-2 B cells (CD21(int)CD24(hi)) were increased in males while transitional-1 B cells (CD23(neg) CD1(neg)) were increased in females at 48 weeks. Autoantibodies to cardiolipin and CD138(+) spleen plasma cells were significantly increased in the aged males but not females. Anti-IgG and anti-C3 immune complex renal deposition were also significantly increased in the prenatal TCDD males but not females. These selective changes in the aged male mice may be noteworthy, in that the prevalence of SLE in humans shifts dramatically toward males with aging. The collective findings in aged mice suggest that prenatal TCDD permanently biases the postnatal immune response in C57BL/6 mice toward autoimmunity, and support a significant B cell component to the induced renal autoimmune disease.

Dimethyl sulfoxide intrauterine therapy in the mare: effects upon endometrial histological features and biopsy classification

The effects upon equine endometrial histological features produced by 10 to 30% concentrations of dimethyl sulfoxide (DMSO) in sterile saline were compared with the effects of sterile saline (0.9% NaCl) alone as an intrauterine infusion therapy in 16 barren mares. No harmful histological changes were noted (P>0.05) as a result of the therapy. Thirty percent intrauterine DMSO therapy produced a significant (P<0.01) improvement (i.e., reduction of chronic inflammatory cell infiltrates and reduction of periglandular fibrosis) in endometrial biopsy classification in 18 of the 27 barren mares evaluated; whereas only 2 of 18 barren mares improved following intrauterine saline treatment in the control group. In subsequent breeding trials, the pregnancy rates following intrauterine therapy were no different between DMSO-treated mares and saline-treated control mares (P>0.05); however, there was a trend toward a higher pregnancy rate following DMSO therapy. The inability to control for sire variability in the breeding trials may have contributed toward the result that no significant difference could be demonstrated in the pregnancy rates between treated and control mares.

Gestational exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin disrupts B-cell lymphopoiesis and exacerbates autoimmune disease in 24-week-old SNF1 mice

Female SNF(1) hybrid mice spontaneously develop an immune complex-mediated glomerulonephritis as early as 24 weeks of age, whereas the disease onset in males is much slower. Further, a rise in concentration of glomerulus-specific autoantibodies via autoreactive B cells is critical to progression of the disease in this strain. Environmental factors contributing to the onset or degree of such autoimmunity are of interest yet poorly understood. In the present study, time-pregnant SWR x NZB dams (10/treatment) were gavaged on gestational 12 with 40 or 80 mg/kg 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), and the SNF(1) offspring were evaluated at 24 weeks of age. Bone marrow B220(low)CD24(-)AA4.1(+) committed B lineage progenitors were increased in female offspring by TCDD, however, committed progenitors and pro-B cells were decreased in males. Splenic marginal zone B cells (CD21(hi)CD24(low-int)) were decreased and follicular B cells (CD21(int)CD24(low)) were increased across sex by prenatal TCDD, whereas transitional-2 B cells (CD21(int)CD24(hi)) and (CD23(low-int) CD1(low-int)) were decreased in males only. Antibodies to double-stranded DNA were significantly increased across sex by TCDD. Anti-IgG and anti-C3 immune complex renal deposition was visibly worsened in females, and present in TCDD-treated males. These data suggest that developmental exposure to TCDD permanently and differentially alters humoral immune function by sex, and exacerbates a type III hypersensitivity lupus-like autoimmune disease in genetically predisposed mice.

An enhanced postnatal autoimmune profile in 24 week-old C57BL/6 mice developmentally exposed to TCDD

Developmental exposure of mice to the environmental contaminant and AhR agonist, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), causes persistent postnatal suppression of T cell-mediated immune responses. The extent to which prenatal TCDD may induce or exacerbate postnatal autoimmune disease remains unknown. In the present study, time-pregnant high affinity AhR C57BL/6 mice received a single oral administration of 0, 2.5, or 5 microg/kg TCDD on gestation day (gd) 12. Offspring of these mice (n=5/gender/treatment) were evaluated at 24 weeks-of-age and showed considerable immune dysregulation that was often gender-specific. Decreased thymic weight and percentages of CD4(+)CD8(+) thymocytes, and increased CD4(+)CD8(-) thymocytes, were present in the female but not male offspring. Males but not females showed decreased CD4(-)CD8(+) T cells, and increased Vbeta3(+) and Vbeta17a(+) T cells, in the spleen. Males but not females also showed increased percentages of bone marrow CD24(-)B220(+) B cell progenitors. Antibody titers to dsDNA, ssDNA and cardiolipin displayed increasing trends in both male and female mice, reaching significance for anti-dsDNA in both genders and for ssDNA in males at 5 microg/kg TCDD. Immunofluorescent staining of IgG and C3 deposition in kidney glomeruli increased in both genders of prenatal TCDD-exposed mice, suggestive of early stages of autoimmune glomerulonephritis. Collectively, these results show that exposure to TCDD during immune system development causes persistent humoral immune dysregulation as well as altered cell-mediated responses, and induces an adult profile of changes suggestive of increased risk for autoimmune disease.

Persistent vulvar hemorrhage secondary to vaginal hemangioma in dogs

Two young female dogs were presented with a chronic history of persistent vulvar hemorrhage. Vaginoscopy was ultimately used to locate bleeding vaginal masses near the urethral papilla. In both cases, episiotomy was performed to resect the mass, and hemangioma was diagnosed histologically. These tumors caused persistent vaginal bleeding; they were difficult to diagnose without vaginoscopy and lavage; and surgical excision was curative in at least one case.

Part I: twenty-year literature overview of veterinary and allopathic medicine

Over the last 20 years, numerous reports, symposia, and workshops have focused on the challenges and changes facing veterinary and allopathic medicine. Many of these have specifically considered the changing economic and demographic profiles of the health professions, the specific roles of health professionals in society, and the importance of professional curricula in meeting changing professional and societal needs. Changing curricula to address future demands is a common thread that runs through all of these reports. Future demands most consistently noted include the fact that modern veterinary curricula must emphasize the acquisition of skills, values, and attitudes in addition to the acquisition of knowledge. Skills relating to business management, strong interpersonal communication, and problem solving have often been noted as lacking in current curricula. Furthermore, future curricula must allow for greater diversification and "specialization" among veterinary students; should promote greater opportunities for an emphasis on public health and population medicine, including food safety, food security, and bio- and agro-terrorism; and should motivate students to be active learners who possess strong lifelong learning skills and attitudes.

Part II: directions and objectives of curriculum structure at veterinary medical and other health professions schools

This article surveys reports on various models and methods of curriculum structure and directions of health professions schools in North America over the past 20 years, with particular emphasis on veterinary and allopathic medical schools. The importance of administrative and faculty leadership, a clear sense of vision, recognition that curricula must change to meet societal needs, and continual, extensive communication and collaboration are discussed as important keys to successfully navigating curriculum reform. The advantages of central versus departmental management of the curriculum are noted with respect to implementing curricular change. Investment in faculty development is essential to ensure sustained cultural and curricular change. As instructional methodology changes, new and better methods of assessing student performance must be developed, with timely and appropriate feedback. Barriers to curriculum change are inevitable; effective strategies must be designed and implemented to navigate these barriers. The future of education in the health professions is clearly in the hands of the educators who prepare future health professionals.

Part III: a case study at the Virginia-Maryland Regional College of Veterinary Medicine

This article presents a history of curriculum revision. Internal and external factors prompting the initial curriculum review included the Pew Report, a vision in the college for reform, and faculty retreats focusing on curriculum. The reformed curriculum was designed around a "core plus elective" strategy and was implemented following development by faculty representatives and approval by college and university levels of review. The curriculum was reviewed after being revised and after new courses were first offered, with further review of a few courses with specific challenges. Outcomes assessment was performed and curricular adjustments made. Challenges that arose during the process included organizing and documenting content as well as communicating the content and philosophy of the new curriculum to the various affected constituencies. A summary of factors considered essential to the successful design, implementation, and review of the new curriculum is presented; the majority of these factors would be applicable to reforms at other institutions.

Bilateral epidiymal cysts in an alpaca male used for breeding

A 4-year-old alpaca stud was presented for examination of his reproductive tract. Ultrasonographic examination of the gonads revealed 2 cystic structures associated with the head of each epididymis. Biopsies of each testicle evidenced mild testicular degeneration. Histopathologic examination of the gonads revealed cystic efferent ductules in the head of each epididymis.

Mycoplasma haemolamae infection in a 4-day-old cria: support for in utero transmission by use of a polymerase chain reaction assay

Blood smear examination in a 4-day-old alpaca revealed massive erythrocyte parasitism by Mycoplasma haemolamae. Blood collected from both the nonparasitemic dam and the cria were positive for M. haemolamae by polymerase chain reaction (PCR) analysis. These findings suggest in utero transmission of M. haemolamae in camelids, even when the dam is not parasitemic.

Molecular analysis of the relatedness of five domesticated turkey strains

Our knowledge of the genetic relatedness among the eight existing domesticated turkey strains is limited. To begin to address this paucity, genetic relatedness among five turkey strains (Blue Slate, Bourbon Red, Narragansett, Royal Palm, and Spanish Black) was investigated using three molecular marker systems: randomly amplified polymorphic DNA (RAPD), microsatellite, and SNPs derived from a sequence tagged site and a cloned RAPD fragment. The RAPD analyses were based on five primers that revealed a total of 14 informative DNA fragments in all five populations. The microsatellite analyses involved two informative alleles from three primer-pairs. A total of nine SNPs were detected, one of which appeared to be strain specific. This SNP formed the basis of a PCR-RFLP genotyping procedure developed to distinguish one of the strains from the other four. Evidence from these analyses including the SNP-based RFLP-PCR suggests that Royal Palm is distinct from the other four strains, though more closely related to Narragansett. These data provide, for the first time, molecular evidence of the potential relationships among noncommercial domesticated turkey strains.

Assessment of the accuracy of computed tomography for measurement of normal equine pituitary glands

OBJECTIVE

To describe the anatomic features of the pituitary gland region in horses via computed tomography (CT) and determine the accuracy of CT for estimating normal equine pituitary gland dimensions.

ANIMALS

25 adult horses with no clinical signs of pituitary disease.

PROCEDURE

Transverse CT images and gross transverse tissue sections were compared in 2 horses. Contrast-enhanced CT of the pituitary gland region was performed postmortem in 23 horses with 4 slice thickness and interval settings (10-mm contiguous or overlapping slices and 4-mm contiguous or overlapping slices). Gross and CT estimates of pituitary gland dimensions were compared via ANOVA. Accuracy of CT estimates was calculated with gross pituitary gland measurements as the known value.

RESULTS

Pituitary glands were located between the temporomandibular joints and had contrast enhancement. Mean gross dimensions were length, 2.11 cm; width, 2.16 cm; height, 0.98 cm; and volume, 2.66 cm3. Gross measurements and CT estimates of pituitary gland length from 10-mm contiguous and overlapping slices did not differ. Gross measurements and CT estimates of pituitary gland width from 4-mm contiguous and overlapping slices did not differ. Estimates of height and volume from all CT techniques differed from gross measurements. Accuracies for CT estimates were length, 88 to 99%; width, 81 to 92%; height, 58 to 71%; and volume, 43 to 55%.

CONCLUSIONS AND CLINICAL RELEVANCE

Accuracy of estimates of pituitary gland dimension in horses varied with CT scanning technique; via CT estimates of length and width of glands were more accurate than estimates of height or volume.

A comparison of the cytologic and histologic features of meningiomas in four dogs

The cytologic and histologic features of 2 intracranial and 2 spinal (extramedullary cervical) canine meningiomas were compared. Cerebrospinal fluid analysis in 2 cases revealed mild, mixed cell pleocytosis, primarily composed of small lymphocytes and monocytoid cells, with a moderate increase in total protein concentration. Cytologic features suggestive of meningioma included cells with both epithelial and mesenchymal characteristics and a tendency towards cell clustering. Tumor location also was useful in making a diagnosis. The 4 meningiomas differed histologically from one another, and included angioblastic, psammomatous, meningotheliomatous, and microcystic anaplastic types, which conformed to a classification scheme for human meningiomas. The classification scheme could not be applied to cytologic specimens.

A possible dominant white gene in Jersey cattle

A white heifer ("Snow") was born in 1991 from coloured registered Jersey parents. She produced six calves sired by coloured Jersey bulls: three white bull calves, two white heifer calves, and one coloured bull calf. One of the white bull calves was mated with 40 Hereford x Friesian yearling heifers (white face, predominantly black body with some white patches). The 38 resulting calves included 16 white and 22 coloured calves. Twelve of the 16 white calves were heifers and four were bulls. Red or black spotting was recorded on some white calves. The results are consistent with an autosomal dominant mutant causing the white phenotype. The mutation appears to have arisen spontaneously in Snow, then passing to her white progeny and white grand-progeny. The white individuals varied from entirely white in a few cases, to most having some residual small areas of red or black pigmentation in patterns not typical of other reported white spotting patterns of cattle.

Evaluation of the bromosulfophthalein 30-minute retention test for the diagnosis of hepatic disease in dogs

The purpose of this study was to evaluate efficacy of bromosulfophthalein (BSP) retention testing in dogs with and without histopathologically confirmed hepatobiliary disease. Medical records of 150 dogs with hepatobiliary disease having both a BSP test and hepatic biopsy were retrieved. Histopathologic slides of liver tissue were reviewed, and dogs were classified according to 1 of 11 histopathologic categories. Twenty-five clinically normal random-source dogs were used as controls for hepatic biopsy and BSP testing. No dogs suffered adverse effects due to BSP administration. BSP retention was significantly (P < .05) higher in hospitalized (13.9%) than control (3.2%) dogs, but the test could not distinguish between hospitalized dogs with different types of hepatobiliary disease. Sensitivity, specificity, and predictive values of BSP retention as a test for hepatic disease were calculated. Using 5.0% as a cutoff for normal BSP retention resulted in a specificity of 88% and a sensitivity of 76%. Using 6.0% as a cutoff for normal BSP retention resulted in a specificity of 100% and a sensitivity of 70%. Dogs of this study having BSP retention of >6% had at least an 86% chance of having an abnormal liver. We concluded that continued use of BSP retention testing is warranted as a noninvasive diagnostic test for liver disease in dogs.

Diffuse annular fusiform adenocarcinoma in a dog

Canine colonic intestinal adenocarcinoma typically presents as rectal polypoid or annular stenotic masses causing clinical signs consistent with large bowel disease. This report discusses an unusual case of intestinal adenocarcinoma in an 11-year-old, neutered male German shepherd dog presented for evaluation of anorexia, profuse watery diarrhea, and weight loss. In this dog, colonic adenocarcinoma diffusely infiltrated the entire large bowel and caused an annular fusiform lesion, as confirmed by endoscopic biopsies and postmortem examination. Other unique features included a paucity of desmoplasia associated with the neoplastic lesion and widespread metastasis to regional lymph nodes, lung, and prostate.

Evidence for the Involvement of CD44 in Endothelial Cell Injury and Induction of Vascular Leak Syndrome by IL-2

At sites of chronic inflammation seen during infections, autoimmunity, graft-vs-host response, and cytokine therapy, endothelial cell injury is known to occur, the exact mechanism of which is unknown. In the current study we used IL-2-induced vascular leak syndrome (VLS) as a model to investigate whether cytotoxic lymphocytes use CD44 in mediating endothelial cell injury. Administration of IL-2 to wild-type mice triggered significant VLS in the lungs and liver. In contrast, in CD44 knockout (KO) mice, IL-2-induced VLS was markedly reduced in the lungs and liver. IL-2-treated wild-type and CD44 KO mice had similar levels of perivascular infiltration with lymphocytes in the lungs and liver. This suggested that the decrease in VLS seen in CD44 KO mice was not due to the inability of lymphocytes to migrate to these organs. Ultrastructural studies demonstrated extensive endothelial cell damage in the lungs and liver of IL-2-treated wild-type, but not CD44 KO, mice. Moreover, CD44-KO mice exhibited a marked decrease in IL-2-induced lymphokine-activated killer cell activity. The induction of VLS was dependent on the expression of CD44 on immune cells rather than endothelial cells because adoptive transfer of CD44+, but not CD44− spleen cells along with IL-2 into CD44 KO mice triggered VLS. The IL-2-induced VLS was blocked by administration of F(ab′)2 of Abs against CD44. The current study demonstrates that CD44 plays a key role in endothelial cell injury. Blocking CD44 in vivo may offer a novel therapeutic approach to prevent endothelial cell injury by cytotoxic lymphocytes in a variety of clinical disease models.

Evidence for the involvement of CD44 in endothelial cell injury and induction of vascular leak syndrome by IL-2

At sites of chronic inflammation seen during infections, autoimmunity, graft-vs-host response, and cytokine therapy, endothelial cell injury is known to occur, the exact mechanism of which is unknown. In the current study we used IL-2-induced vascular leak syndrome (VLS) as a model to investigate whether cytotoxic lymphocytes use CD44 in mediating endothelial cell injury. Administration of IL-2 to wild-type mice triggered significant VLS in the lungs and liver. In contrast, in CD44 knockout (KO) mice, IL-2-induced VLS was markedly reduced in the lungs and liver. IL-2-treated wild-type and CD44 KO mice had similar levels of perivascular infiltration with lymphocytes in the lungs and liver. This suggested that the decrease in VLS seen in CD44 KO mice was not due to the inability of lymphocytes to migrate to these organs. Ultrastructural studies demonstrated extensive endothelial cell damage in the lungs and liver of IL-2-treated wild-type, but not CD44 KO, mice. Moreover, CD44-KO mice exhibited a marked decrease in IL-2-induced lymphokine-activated killer cell activity. The induction of VLS was dependent on the expression of CD44 on immune cells rather than endothelial cells because adoptive transfer of CD44+, but not CD44- spleen cells along with IL-2 into CD44 KO mice triggered VLS. The IL-2-induced VLS was blocked by administration of F(ab')2 of Abs against CD44. The current study demonstrates that CD44 plays a key role in endothelial cell injury. Blocking CD44 in vivo may offer a novel therapeutic approach to prevent endothelial cell injury by cytotoxic lymphocytes in a variety of clinical disease models.

Evaluation of canine lumbosacral stenosis using intravenous contrast-enhanced computed tomography

The objective of this study was to evaluate intravenous contrast-enhanced computed tomography as a technique for predicting the within-level location(s) of compressive soft tissues in the canine lumbosacral spine. Pre-operative intravenous contrast-enhanced computed tomography of the L5-S3 vertebral levels was performed in 12 consecutive large breed dogs with lumbosacral stenosis. The images were evaluated for enhancement of soft tissues by two radiologists who were unaware of the surgical findings. For each within-level location (dorsal canal, ventral canal, right lateral recess, left lateral recess) enhancement was classified as present, absent or equivocal. The results were compared with the results of surgical exploration and histopathology of excised tissues. The positive predictive values of intravenous contrast-enhanced computed tomography for compressive soft tissues involving the dorsal canal, ventral canal and lateral recesses were 83%, 100%, and 81% respectively. Negative predictive values for compressive soft tissues involving these locations were 29%, 50%, and 40% respectively.

Evidence for the involvement of Fas ligand and perforin in the induction of vascular leak syndrome

Endothelial cell injury resulting in vascular leak syndrome (VLS) is one of the most widely noted phenomenons in a variety of clinical diseases. In the current study we used IL-2-induced VLS as a model to investigate the role of cytolytic lymphocytes in the cytotoxicity of endothelial cells. Administration of IL-2 (75,000 U/mouse, three times a day for 3 days) into BL/6 wild-type mice triggered significant VLS in the lungs, liver, and spleen. Interestingly, perforin-knockout (KO) mice exhibited a marked decrease in IL-2-induced VLS in all three organs tested. Also, Fas ligand-defective (gld) mice and Fas-deficient (lpr) mice exhibited decreased VLS in the liver and spleen, but not in the lungs. The decreased VLS seen in perforin-KO, gld, and lpr mice was not due to any defect in lymphocyte migration or homing to various organs because histopathologic studies in these mice demonstrated significant and often greater perivascular infiltration of lymphocytes compared with the IL-2-treated wild-type mice. Ultrastructural studies of the lungs demonstrated significant damage to the endothelial cells in IL-2-treated wild-type mice and decreased damage in perforin-KO mice. IL-2 administration caused up-regulation of CD44 in all strains of mice tested and triggered increased LAK activity against an endothelial cell line in wild-type and gld mice, but not in perforin-KO mice. The current study demonstrates for the first time that perforin and Fas ligand may actively participate in endothelial cell injury and induction of VLS in a variety of organs.

Evidence for the Involvement of Fas Ligand and Perforin in the Induction of Vascular Leak Syndrome

Endothelial cell injury resulting in vascular leak syndrome (VLS) is one of the most widely noted phenomenons in a variety of clinical diseases. In the current study we used IL-2-induced VLS as a model to investigate the role of cytolytic lymphocytes in the cytotoxicity of endothelial cells. Administration of IL-2 (75,000 U/mouse, three times a day for 3 days) into BL/6 wild-type mice triggered significant VLS in the lungs, liver, and spleen. Interestingly, perforin-knockout (KO) mice exhibited a marked decrease in IL-2-induced VLS in all three organs tested. Also, Fas ligand-defective (gld) mice and Fas-deficient (lpr) mice exhibited decreased VLS in the liver and spleen, but not in the lungs. The decreased VLS seen in perforin-KO, gld, and lpr mice was not due to any defect in lymphocyte migration or homing to various organs because histopathologic studies in these mice demonstrated significant and often greater perivascular infiltration of lymphocytes compared with the IL-2-treated wild-type mice. Ultrastructural studies of the lungs demonstrated significant damage to the endothelial cells in IL-2-treated wild-type mice and decreased damage in perforin-KO mice. IL-2 administration caused up-regulation of CD44 in all strains of mice tested and triggered increased LAK activity against an endothelial cell line in wild-type and gld mice, but not in perforin-KO mice. The current study demonstrates for the first time that perforin and Fas ligand may actively participate in endothelial cell injury and induction of VLS in a variety of organs.

Multicentric lymphosarcoma with ovarian involvement in a Nubian goat

Multiple lymph node enlargement and an intra-abdominal mass were diagnosed in a 6-year-old doe. Necropsy revealed lymphosarcoma involving multiple organs, including the ovaries. Lymphosarcoma is rare in goats; ovarian involvement has not previously been reported.

Systemic and local effects associated with long-term epidural catheterization and morphine-detomidine administration in horses

OBJECTIVE

The purpose of this study was to determine the systemic and local effects associated with long-term epidural catheterization and epidural morphine-detomidine administration in horses.

STUDY DESIGN

Development of systemic or local effects was assessed by placing caudal epidural catheters in study horses and administering injections through the catheters every 12 hours for 14 days.

ANIMALS

Ten horses with epidural catheters that received daily injections; six uncatheterized horses presented for euthanasia.

METHODS

Horses received either 0.2 mg/kg morphine sulfate and 30 micrograms/kg detomidine hydrochloride or an equivalent volume of physiologic saline solution through epidural catheters. Systemic effects were compared between control and treatment horses by measuring physical parameters and hay and water consumption, as well as by evaluating major organs after euthanasia. Local effects were studied by examining cerebrospinal fluid and by grading representative samples of the spinal cord and surrounding tissues histologically for inflammation and fibrosis. Local effects were compared between control and treatment horses, as well as between catheterized (control plus treatment) horses and uncatheterized horses.

RESULTS

No significant difference was identified in daily variables or hay and water consumption between control and treatment horses. No growth was obtained from cerebrospinal fluid cultures. No significant difference in cerebrospinal fluid values or spinal tissue inflammation or fibrosis grades was shown between control and treatment horses. However, when compared with uncatheterized horses, cerebrospinal fluid red blood cell values were marginally higher and protein concentrations were significantly higher in the catheterized group. Lumbosacral and sacral spinal tissue segment inflammation grades, and sacral segment fibrosis grades were significantly higher in catheterized horses.

CONCLUSIONS

Long-term epidural administration of a morphine-detomidine combination is not associated with apparent adverse systemic effects in horses. Localized inflammation and fibrosis seem to be catheter-related.

CLINICAL RELEVANCE

Potential systemic and local effects are important considerations with long-term administration of a morphine-detomidine combination through indwelling epidural catheters for alleviation of chronic musculoskeletal pain in horses.

Efficacy of an epidural combination of morphine and detomidine in alleviating experimentally induced hindlimb lameness in horses

Amphotericin B-induced synovitis of the left tarsocrural joint was used to create a grade 3 of 4 lameness in 11 horses. Caudal epidural catheters were placed and advanced to the lumbosacral region. Baseline heart and respiratory rates were recorded and horses were videotaped at a walk and trot. Morphine sulphate (0.2 mg/kg) and detomidine hydrochloride (30 micrograms/kg) were administered to treated horses (n = 8) through the epidural catheter; an equivalent volume of physiologic saline solution was administered to control horses (n = 3) through the catheter. At hourly intervals after epidural injection for a total of 6 hours, heart and respiratory rates were recorded, and horses were videotaped walking and trotting. At the end of the observation period, video recordings were scrambled onto a master videotape. Lamenesses were scored by three investigators unaware of group assignment or treatment time. Lameness scores, heart rates, and respiratory rates were compared between groups using repeated measures analysis of variance. There was a significant decrease in lameness score after treatment with epidural morphine and detomidine (P = .0003); average lameness scores of treated horses were less than grade 1 at each hourly observation for 6 hours after drug administration. Early in the observation period, heart rates significantly increased in control horses and decreased in treated horses (P = .03). A similar trend occurred for respiratory rates (P = .07). Results of this study demonstrate that epidural administration of a combination of morphine and detomidine is capable of providing profound hindlimb analgesia in horses.

Inheritance of goat coat colors

Goat color inheritance was evaluated based on color description of 218 kids and their parents (10 sires, 178 dams) from mixed crosses between several goat populations in an experiment on cashmere fiber production. Altogether 10 color patterns were observed. They were postulated to be caused by 10 alleles at the Agouti locus, with the allele for white or tan color being the top dominant allele, and the nine others codominant. The bottom recessive allele, for nonagouti color, was the 11th allele at this locus. The postulated alleles are white or tan (A(wt)), black mask (A(blm)), bezoar (A(bz)), badgerface (A(b)), grey (A(g)), lightbelly (A(lb)), swiss markings (A(sm)), lateral stripes (A(ls)), mahogany (A(mh)), red cheek (A(rc)), and nonagouti (Aa). Two types of eumelanin pigment were observed, black and light brown, the latter being dominant. Recessive brown was not observed.

Spontaneous uterine infections are associated with elevated prostaglandin F2α metabolite concentrations in postpartum dairy cows

Postpartum Holstein (n=21) and Jersey (n=4) cows were used to determine if uterine infections are associated with elevated plasma concentrations of 13,14-dihydro-15-keto-prostaglandin F(2)alpha (PGFM). Based upon clinical examinations and bacterial content of intrauterine fluid samples, cows detected with uterine infections between 21 and 28 d post partum were used (infected; n=14). These cows were matched with herdmates that were free of infection (control; n=11). Beginning on the day the cows were assigned to the experiment (Day 1), blood samples were collected on alternate days for the next 14 to 15 d. Plasma samples were stored at -20 degrees C until assayed. From Day 1 until the end of the experiment, uterine fluid samples were collected transcervically twice weekly for aerobic bacterial culture. Endometrial biopsies were collected between Days 6 and 8 and Days 13 and 15. Control cows did not show signs of uterine infection throughout the trial, and bacterial cultures indicated that there were no significant bacterial populations in the uteri of the control cows. The uteri of infected cows harbored numerous microbes. Actinomyces pyogenes was most prominent. Various species of Streptococcus and Pasteurella were also prevalent in the infected cows. Escherichia coli was present in the uterus of both infected and control cows. Biopsies showed that infected cows had more (P<0.05) neutrophils, plasma cells and lymphocytes in the endometrium than did the control cows. As determined by plasma progesterone concentrations, 83% of the control and 50% of the infected cows had functional luteal tissue during the 2-wk sampling period. Plasma PGFM profiles were linear (P<0.03) and did not differ between treatment groups (P>0.01). However, average plasma PGFM concentrations were greater (P<0.0001) in infected than in control cows. These data indicate that plasma PGFM concentrations are greater in postpartum cows with spontaneous uterine infections then in herdmates free of infection.

Immunologic studies of a horse with lymphosarcoma

Immunological, clinical, and pathological investigations were conducted on a horse with lymphosarcoma. The immunological status was investigated by measuring the level of antibodies by single radial immunodiffusion test and the ability of lymphocytes to proliferate in response to mitogens. Multiple immunological abnormalities were noted in this horse. They were; (1) decreased IgM, IgG, and IgA levels in the serum despite hyperproteinemia; (2) increased in-vitro spontaneous lymphoproliferation which reflects augmented mitosis; (3) decreased lymphoproliferative response to T cell stimulants (e.g. Concanavalin-A (Con-A)) suggesting impaired T cell activation; (4) presence of immunosuppressive factors in serum as demonstrated by in-vitro lymphocyte culture systems. Clinical pathology findings revealed an unusual monoclonal alpha peak in the serum and morphologically abnormal lymphocytes distributed throughout the body. Serum fractionated by fast protein liquid chromatography (FPLC) revealed that the immunosuppressive factors were found in this abnormal alpha peak. The immunopathological findings in this horse are discussed.

Tyzzer's disease in a neonatal cockatiel

A 4-day-old cockatiel that died suddenly had a pale, mottled liver at necropsy. Extensive necrosis and numerous bacilli were present microscopically in the liver. The organism was identified as Bacillus piliformis, the causative agent of Tyzzer's disease, by special staining and electron microscopy. This is the first report of Tyzzer's disease in an avian species.