Preantral follicle numbers and size in heifers carrying Trio, a bovine high fecundity allele.

In brief: The bovine high fecundity allele, Trio, results in the occurrence of multiple ovulations and is characterized by antral follicles that develop slower and acquire ovulatory capacity at smaller sizes. This study provides novel information on the effect of the Trio allele on early folliculogenesis. Abstract: The bovine high fecundity allele, Trio, causes overexpression in granulosa cells (GCs) of SMAD6, an inhibitor of BMP15-activated SMAD signalling. Furthermore, the Trio allele results in antral follicles that develop slower, acquire ovulatory capacity at smaller sizes, and have three-fold greater ovulation rate compared to half-sib non-carriers. The present study was designed to determine preantral follicle numbers and size in Trio carrier and non-carrier cattle testing the hypothesis that inhibition of SMAD signalling would alter preantral follicle activation and/or growth. Ovarian tissues from Trio carrier (n = 12) and non-carrier (n = 12) heifers were obtained by laparotomy after follicle wave synchronization. Follicle numbers and dimensions were determined for each stage of development (primordial, transitional, primary, and secondary) from paraffin-embedded sections. There were no differences in the number of primordial, transitional, or secondary follicles or in antral follicle count, circulating AMH, or ovarian volume between carriers and non-carriers. Trio carriers had ~2.5-fold greater (P < 0.01) number of primary follicles than non-carriers, and transitional and primary follicles were larger (~1.2-fold; P < 0.1) in Trio carriers. Oocyte volume of primordial and transitional follicles was not different between genotypes; however, oocytes were larger (P < 0.05) in primary (~1.3-fold) and secondary (~1.8-fold) follicles for Trio carriers. Granulosa cell numbers were not different (P > 0.3) between carriers and non-carriers, irrespective of the stage of development. These results suggest that, after primordial follicle activation, follicles in Trio carrier cattle have slower progression through the primary stage, hence the larger oocyte and greater number of primary follicles.

Metastatic carcinoma of unknown origin in a dog.

Although cancer of unknown primary origin (CUP) is well-described in the human literature, it is not as well-understood within veterinary medicine. This case report represents one of few focused on describing CUP in a dog. Key clinical message: Metastatic CUP should be considered as a differential diagnosis despite being a rare disease entity that is infrequently reported within the veterinary literature.

Carcinome métastatique d'origine inconnue chez un chien. Bien que le cancer d'origine primaire inconnue (CUP) soit bien décrit dans la littérature humaine, il n'est pas aussi bien compris en médecine vétérinaire. Ce rapport de cas représente l'un des rares à s'intéresser à la description du CUP chez un chien.Message clinique clé:Le CUP métastatique doit être considéré comme un diagnostic différentiel bien qu'il s'agisse d'une entité de maladie rare rarement rapportée dans la littérature vétérinaire.(Traduit par Dr Serge Messier).

Diagnostic accuracy of optical coherence tomography for assessing surgical margins of canine soft tissue sarcomas in observers of different specialties.

OBJECTIVE: To determine the diagnostic accuracy of optical coherence tomography (OCT) to assess surgical margins of canine soft tissue sarcoma (STS) and determine the influence of observer specialty and training. STUDY DESIGN: Blinded clinical prospective study. ANIMALS: Twenty-five dogs undergoing surgical excision of STS. METHODS: In vivo and ex vivo surgical margins were imaged with OCT after tumor resection. Representative images and videos were used to generate a training presentation and data sets. These were completed by 16 observers of four specialties (surgery, radiology, pathology, and OCT researchers). Images and videos from data sets were classified as cancerous or noncancerous. RESULTS: The overall sensitivity and specificity were 88.2% and 92.8%, respectively, for in vivo tissues and 82.5% and 93.3%, respectively, for ex vivo specimens. The overall accurate classification for all specimens was 91.4% in vivo and 89.5% ex vivo. There was no difference in accuracy of interpretation of OCT imaging by observers of different specialties or experience levels. CONCLUSION: Use of OCT to accurately assess surgical margins after STS excision was associated with a high sensitivity and specificity among various specialties. Personnel of all specialties and experience levels could effectively be trained to interpret OCT imaging. CLINICAL SIGNIFICANCE: Optical coherence tomography can be used by personnel of different specialty experience levels and from various specialties to accurately identify canine STS in vivo and ex vivo after a short training session. These encouraging results provide evidence to justify further research to assess the ability of OCT to provide real-time assessments of surgical margins and its applicability to other neoplasms.

Hormone-responsive organoids from domestic mare and endangered Przewalski's horse endometrium.

The endometrium, the inner uterine lining, is composed of cell layers that come in direct contact with an embryo during early pregnancy and later with the fetal placenta. The endometrium is responsible for signals associated with normal reproductive cyclicity as well as maintenance of pregnancy. In the mare, functionally competent in vitro models of the endometrium have not been successful. Furthermore, the ability to study various reproductive processes in vitro may allow critical evaluation of signaling pathways involved in the reproductive diseases of animals that cannot be handled frequently, such as various wildlife species. Here we report the establishment of organoids, 3D structures, derived from fresh and frozen-thawed equine endometrium (Equus ferus caballus and E. f. przewalskii). Although organoids from domestic mares responded to exogenous hormonal stimuli, organoids from Przewalski's horse failed to respond to exogenous hormones. The present study represents a 'first' for any large animal model or endangered species. These physiologically functional organoids may facilitate improved understanding of normal reproductive mechanisms, uterine pathologies, and signaling mechanisms between the conceptus and endometrium and may lead to the development of novel bioassays for drug discovery.

Characterization of WWOX expression and function in canine mast cell tumors and malignant mast cell lines.

BACKGROUND: The WW domain-containing oxidoreductase (WWOX) tumor suppressor gene is frequently lost in a variety of solid and hematopoietic malignancies in humans. Dysregulation of WWOX has been implicated as playing a key role in tumor cell survival, DNA damage repair, and genomic stability. The purpose of this study was to characterize WWOX expression in spontaneous canine mast cell tumors (MCTs) and malignant cell lines and investigate the potential contribution of WWOX loss on malignant mast cell behavior. METHODS/RESULTS: WWOX expression is decreased in primary canine MCTs and malignant mast cell lines compared to normal canine bone marrow-cultured mast cells. In transformed canine mastocytoma cell lines, overexpression of WWOX or WWOX knockdown had no effect on mast cell viability. Inhibition of WWOX enhanced clonogenic survival following treatment with ionizing radiation in the C2 mast cell line. Lastly, immunohistochemistry for WWOX was performed using a canine MCT tissue microarray, demonstrating that WWOX staining intensity and percent of cells staining for WWOX is decreased in high-grade MCTs compared to low-grade MCTs. CONCLUSIONS: These data suggest that WWOX expression is attenuated or lost in primary canine MCTs and malignant mast cell lines. Given the observed increase in clonogenic survival in WWOX-deficient C2 mast cells treated with ionizing radiation, further investigation of WWOX and its role in mediating the DNA damage response in malignant mast cells is warranted.

Nylon Fibered Versus Non-Fibered Embolization Coils: Comparison in a Swine Model.

PURPOSE: To determine whether nylon fibers improve the performance of platinum embolization coils in porcine arteries. MATERIALS AND METHODS: Platinum 0.035" embolization coils, both with and without nylon fibers, were used to embolize a total of 24 hindlimb arteries in 6 swine: 12 with fibered coils and 12 with non-fibered coils. Apart from fibers, the coils were identical. Immediate and late results were studied, including number of coils needed to achieve vessel occlusion and durability of occlusion at 1 and 3 months. Arteriographic as well as histopathologic analysis were performed. RESULTS: A mean of 3.2 (range, 2-4) non-fibered coils was required to achieve occlusion, whereas a mean of 1.3 (range, 1-2) fibered coils achieved occlusion in similarly sized arteries (2.3-3.2-mm diameter, P < .001). The mean percent cross-sectional area occupied by thrombus was greater in arteries with fibered coils than with non-fibered coils at 1 month (63% ± 6% and 48% ± 15%, respectively, P = .03) but not at 3 months (61% ± 6% and 49% ± 15%, respectively, P = .06). Some recanalization was observed at follow-up and did not differ between groups at 1 month (P = .07) or 3 months (P = .22). CONCLUSIONS: Nylon fibers allow significantly fewer embolization coils to achieve acute occlusion of arteries compared to bare metal coils. Both fibered and non-fibered coils showed recanalization at follow-up.

Dimethyl sulfoxide maintains structure and function of cryopreserved equine endometrial explants.

Availability of viable frozen-thawed endometrial tissues could facilitate detailed studies into physiologic and disease processes influencing the endometrium. This study was designed to investigate the cryosurvival of equine endometrial tissue. Previous studies in the human and horse have focused on cryopreservation of dissociated endometrial cells. To our knowledge, there are no studies on cryopreservation of endometrial explants. Our objectives were to 1) determine the influence of differing concentrations of the permeating cryoprotectant dimethyl sulfoxide (Me2SO) on viability, structural integrity, and gene expression of cryopreserved equine endometrial tissues prior to and following a 5-day explant culture in vitro and 2) examine the influence of low (1000 mg/L dextrose) vs high (4500 mg/L dextrose) glucose medium during in vitro culture. Both 10% and 20% (v/v) concentrations of Me2SO maintained viability following cryopreservation and in vitro culture. In addition, gene expression remained unaltered following cryopreservation with either 10% or 20% Me2SO. However, tissue structural integrity was slightly reduced compared to the fresh control. Furthermore, there was no difference in structural integrity, cell viability, or gene expression between low and high glucose medium during in vitro culture. Although E-cadherin and Ki67 gene expression was not different among fresh, 10% Me2SO, and 20% Me2SO treatments prior to or following tissue culture, estrogen receptor-α and progesterone receptor gene expression were reduced in all groups after explant culture. This is the first report of successful cryopreservation of equine endometrial explants.

Enhanced Rotator-Cuff Repair Using Platelet-Rich Plasma Adsorbed on Branched Poly(ester urea)s.

Platelet-rich plasma (PRP) is a clinically relevant source of growth factors used commonly by surgeons. The clinical efficacy of PRP use as reported in the literature is widely variable which is likely attributed to poorly defined retention time of PRP at the repair site. To overcome this limitation, branched poly(ester urea) (PEU) nanofibers were used to adsorb and retain PRP at the implant site in an acute rotator-cuff tear model in rats. The adsorption of PRP to the branched-PEU 8% material was characterized using quartz crystal microbalance (QCM) and immuno-protein assay. After adsorption of PRP to the nanofiber sheet, the platelets actively released proteins. The adhesion of platelets to the nanofiber material was confirmed by immunofluorescence using a p-selectin antibody. In vivo testing using a rat rotator-cuff repair model compared five groups; no repair (control), suture repair only, repair with disc implant (Disc), repair with PRP-soaked disc (Disc PRP), and a PRP injection (PRP). Mechanical testing at 84 d for the four surgical repair groups resulted in a higher stiffness (11.8 ± 3.8 N/mm, 13.5 ± 3.8 N/mm, 16.8 ± 5.8 N/mm, 12.2 ± 2.6 N/mm, respectively) for the Disc PRP group. Histological staining using trichrome, hematoxylin, and eosin Y (H&E), and safranin O confirmed more collagen organization in the Disc PRP group at 21 and 84 d. Limited inflammation and recovery toward preoperative mechanical properties indicate PEU nanofiber discs as translationally relevant.

Heat-shock protein 70 expression in the equine cornea.

OBJECTIVE: Expression of the 70-kDa heat-shock protein (HSP70) has been demonstrated in normal canine corneal epithelium, and inducible expression has been suggested to facilitate wound resolution through organized migration, proliferation, and adhesion of the corneal epithelial cells. Diminished expression of HSP70 may therefore contribute to prolonged healing in the pathologic cornea of other companion animal species, including the horse. ANIMAL STUDIED: Normal and pathologic equine cornea was evaluated to determine whether the expression of HSP70 is correlated with appropriate corneal epithelial wound healing. PROCEDURES: Paraffin-embedded tissue from normal equine cornea and therapeutic keratectomies of sterile keratopathies was subject to routine immunohistochemistry for HSP70. RESULTS: Normal equine corneas exhibited the baseline expression of HSP70 in the nuclei of all epithelial cells as well as the cytoplasm of the basal epithelium. Expression of HSP70 in suspected immune-mediated keratitis was localized to the cytoplasm of basal epithelial cells and nuclei of all epithelial cells, similar to the normal equine cornea. Expression in indolent ulcers was diminished; weak, diffuse staining was noted in the cytoplasm of all epithelial cells. CONCLUSIONS: These findings suggest the expression of HSP70 is induced in the normal equine cornea during re-epithelialization and may be altered in sterile keratopathies.

Canine pulmonary adenocarcinoma tyrosine kinase receptor expression and phosphorylation.

BACKGROUND: This study evaluated tyrosine kinase receptor (TKR) expression and activation in canine pulmonary adenocarcinoma (cpAC) biospecimens. As histological similarities exist between human and cpAC, we hypothesized that cpACs will have increased TKR mRNA and protein expression as well as TKR phosphorylation. The molecular profile of cpAC has not been well characterized making the selection of therapeutic targets that would potentially have relevant biological activity impossible. Therefore, the objectives of this study were to define TKR expression and their phosphorylation state in cpAC as well as to evaluate the tumors for the presence of potential epidermal growth factor receptor (EGFR) tyrosine kinase activating mutations in exons 18-21. Immunohistochemistry (IHC) for TKR expression was performed using a tissue microarray (TMA) constructed from twelve canine tumors and companion normal lung samples. Staining intensities of the IHC were quantified by a veterinary pathologist as well as by two different digitalized algorithm image analyses software programs. An antibody array was used to evaluate TKR phosphorylation of the tumor relative to the TKR phosphorylation of normal tissues with the resulting spot intensities quantified using array analysis software. Each EGFR exon PCR product from all of the tumors and non-affected lung tissues were sequenced using sequencing chemistry and the sequencing reactions were run on automated sequencer. Sequence alignments were made to the National Center for Biotechnology Information canine EGFR reference sequence. RESULTS: The pro-angiogenic growth factor receptor, PDGFRα, had increased cpAC tumor mRNA, protein expression and phosphorylation when compared to the normal lung tissue biospecimens. Similar to human pulmonary adenocarcinoma, significant increases in cpAC tumor mRNA expression and receptor phosphorylation of the anaplastic lymphoma kinase (ALK) tyrosine receptor were present when compared to the corresponding normal lung tissue. The EGFR mRNA, protein expression and phosphorylation were not increased compared to the normal lung and no activating mutations were identified in exons 18-21. CONCLUSIONS: Canine pulmonary adenocarcinoma TKRs are detected at both the mRNA and protein levels and are activated. Further investigation into the contribution of TKR activation in cpAC tumorigenesis is warranted.

Characterization of the contributions of Hp-MMP 9 to the serum acute phase protein response of lipopolysaccharide challenged calves.

BACKGROUND: Bovine respiratory disease (BRD) is a costly feature of modern cattle production. Early and accurate detection of BRD may prove useful in the successful management of this disease. The primary objective of the study was to define the time course of covalent complexes of neutrophil, haptoglobin (Hp) and matrix metalloproteinase 9 (Hp-MMP 9) in serum after intravenous lipopolysaccharide (LPS) in comparison to traditional markers. Our hypothesis was that serum concentrations of neutrophil Hp-MMP 9 provides information distinct from traditional acute phase protein markers. To characterize the neutrophil responses to lipopolysaccharide (E. coli; O111:B4; 2.5 µg/kg body weight), nine healthy, Jersey calves (65-82 days of age; 74.5 ± 13.1 kg) were challenged and physiologic parameters, peripheral blood cell counts and serum cortisol (C), Hp-MMP 9, Hp, alpha1-acid glycoprotein (AGP), serum amyloid A (SAA) were obtained starting 24 hours before to 96 hours post-LPS challenge. RESULTS: Physiologic parameters (temperature, pulse, respiratory rate) and attitude assessed at each time point indicated that LPS challenge resulted in rapid onset of depression, tachypnea, leukopenia, neutropenia and lymphopenia within 1 hour. Serum C concentrations were significantly increased by 1 hour post-LPS. Serum Hp-MMP 9 complexes were detectable in serum by 0.5 hours and peaked at 16 h, serum total Hp remained <10 µg/mL until 8 hours post LPS infusion and were significantly greater than baseline by 12 hours post-LPS infusion. Serum amyloid A concentrations increased significantly by 8 hours post LPS. Serum concentrations of AGP increased significantly by 16 hours post LPS. Serum concentrations of Hp, SAA and AGP remained significantly greater than baseline out to 96 hours post-LPS. The total systemic exposure to traditional makers is significantly greater than from Hp-MMP 9 CONCLUSION: Using a well described model for acute phase protein responses, the data demonstrate that serum neutrophil Hp-MMP 9 complexes appear sooner and decline more rapidly than other acute phase proteins (APP). Since Hp-MMP9 is stored pre-formed, it provides information specifically addressing the LPS-induced activation of bovine neutrophils. Contributions of Hp-MMP 9 to the serum acute phase protein response may provide useful information, independent of hepatic responses, in diagnosis of acute inflammation.

Severe bronchiectasis resulting from chronic bacterial bronchitis and bronchopneumonia in a jungle cat.

Bronchiectasis is irreversible bronchial dilation that can be congenital or acquired secondary to chronic airway obstruction. Feline bronchiectasis is rare and, to our knowledge, has not been reported previously in a non-domestic felid. An ~10-y-old female jungle cat (Felis chaus) was presented for evaluation of an abdominal mass and suspected pulmonary metastasis. The animal died during exploratory laparotomy and was submitted for postmortem examination. Gross examination revealed consolidation of the left caudal lung lobe and hila of the cranial lung lobes. Elsewhere in the lungs were several pale-yellow pleural foci of endogenous lipid pneumonia. On cut section, there was severe distension of bronchi with abundant white mucoid fluid. The remaining lung lobes were multifocally expanded by marginal emphysema. Histologically, ectatic bronchi, bronchioles, and fewer alveoli contained degenerate neutrophils, fibrin, and mucin (suppurative bronchopneumonia) with rare gram-negative bacteria. Aerobic culture yielded low growth of Proteus mirabilis and Escherichia coli. There was chronic bronchitis, marked by moderate bronchial gland hyperplasia, lymphoplasmacytic inflammation, and lymphoid hyperplasia. The palpated abdominal mass was a uterine endometrial polyp, which was considered an incidental, but novel, finding. Chronic bronchitis and bronchopneumonia should be considered as a cause of bronchiectasis and a differential diagnosis for respiratory disease in non-domestic felids.

Loss of Paneth cells dysregulates gut ILC subsets and enhances weight gain response to high fat diet in a mouse model.

Obesity has been associated with dysbiosis, but innate mechanisms linking intestinal epithelial cell subsets and obesity remain poorly understood. Using mice lacking Paneth cells (Sox9 ΔIEC mice), small intestinal epithelial cells specialized in the production of antimicrobial products and cytokines, we show that dysbiosis alone does not induce obesity or metabolic disorders. Loss of Paneth cells reduced ILC3 and increased ILC2 numbers in the intestinal lamina propria. High-fat diet (HFD) induced higher weight gain and more severe metabolic disorders in Sox9 ΔIEC mice. Further, HFD enhances the number of ILC1 in the intestinal lamina propria of Sox9 ΔIEC mice and increases intestinal permeability and the accumulation of immune cells (inflammatory macrophages and T cells, and B cells) in abdominal fat tissues of obese Sox9 ΔIEC . Transplantation of fecal materials from Sox9 ΔIEC mice in germ-free mice before HFD further confirmed the regulatory role of Paneth cells for gut ILC subsets and the development of obesity.

Generation and cryopreservation of feline oviductal organoids.

Next-generation in vitro culture model systems are needed to study the reproductive pathologies that affect domestic animals. These 3D culture models more closely mimic normal physiological function to allow a greater understanding of reproductive pathology and to trial therapeutics without the welfare concerns and the increased time and cost associated with live animal research. Recent advances with in vitro cell culture systems utilizing human and laboratory animal tissues have been reported, but implementation of these technologies in veterinary species has been slower. Organoids are a physiologically representative 3D cell culture system that can be maintained long-term. By combining organoid culture with cryopreservation, a long-term, experimental model can be available for year-round application, thus bypassing seasonality and reproductive tract availability restrictions. Here we report the generation and cryopreservation of feline oviductal organoids for the first time. Optimal culture medium for the generation of feline oviductal organoids was established, and organoids were successfully cryopreserved using three different freezing media with organoids from each treatment demonstrating comparable viability, growth rate, and protein expression after thawing and culture. Feline oviductal organoids may facilitate an in vivo-like environment that, in conjunction with co-culture for in vitro maturation and in vitro fertilization, may positively influence in vitro gamete and embryo development, embryo quality, and pregnancy rates after embryo transfer in domestic and nondomestic felids. Furthermore, readily available cryopreserved feline oviductal organoids will facilitate this co-culture, which is of particular importance to endangered felid breeding programs where tissue and gamete samples are often opportunistically obtained with little or no notice.

Factors Affecting Pregnancy Success in the Bitch Following Transcervical Insemination.

Endoscopic-assisted transcervical inseminations (TCIs) have become increasingly popular. The aim of this retrospective clinical study was to evaluate data from the TCIs performed at our facility. We evaluated data from January 2018 through December 2021. This included 137 cases with fresh, 67 cases chilled, and 63 cases using frozen-thawed semen. All bitches underwent breeding management to determine the ideal breeding period. All semen samples were evaluated for total number of sperm, total motility, and progressive motility. Pregnancy was determined by B-mode ultrasonography about 4 weeks after the breeding. Litter size was determined by radiographs performed around the last week of gestation. The pregnancy rate was 83.21% for fresh, 67.16% for chilled, and 66.67% for frozen-thawed semen. There was a significant difference in litter size between fresh semen (6.82 puppies per litter) and both chilled (5.21 puppies per litter) and frozen-thawed (4.59 puppies per litter) semen (P < .05). There was no significant difference in litter size between chilled and frozen-thawed semen. There was no difference in pregnancy rates between clinicians performing the inseminations. Pregnancy rate was not different when sedation was used for the insemination (66.67%) compared to when sedation was not used (74.84%; P > .05). Performing 2 TCIs during the fertile period, regardless of the semen type, resulted in an increase of 6.6% in pregnancy rate (P > .05) and an increase of 0.7 puppies per litter, on average (P > .05). These results can be used to help guide recommendations for breeding clients on the best options to increase both pregnancy rate and litter size for their breeding.

Cyclosporine-induced immune suppression alters establishment of HTLV-1 infection in a rabbit model.

Human T-lymphotropic virus type 1 (HTLV-1) infection causes adult T-cell leukemia and several lymphocyte-mediated inflammatory diseases. Persistent HTLV-1 infection is determined by a balance between host immune responses and virus spread. Immunomodulatory therapy involving HTLV-1-infected patients occurs in a variety of clinical settings. Knowledge of how these treatments influence host-virus relationships is not understood. In this study, we examined the effects of cyclosporine A (CsA)-induced immune suppression during early infection of HTLV-1. Twenty-four New Zealand white rabbits were split into 4 groups. Three groups were treated with either 10 or 20 mg/kg CsA or saline before infection. The fourth group was treated with 20 mg/kg CsA 1 week after infection. Immune suppression, plasma CsA concentration, ex vivo lymphocyte HTLV-1 p19 production, anti-HTLV-1 serologic responses, and proviral load levels were measured during infection. Our data indicated that CsA treatment before HTLV-1 infection enhanced early viral expression compared with untreated HTLV-1-infected rabbits, and altered long-term viral expression parameters. However, CsA treatment 1 week after infection diminished HTLV-1 expression throughout the 10-week study course. Collectively, these data indicate immunologic control is a key determinant of early HTLV-1 spread and have important implications for therapeutic intervention during HTLV-1-associated diseases.

Optical coherence tomography for surgical margin evaluation of excised canine cutaneous and subcutaneous tumours.

Currently, intraoperative tumour margin imaging is not routinely utilized in veterinary medicine. Optical coherence tomography (OCT) allows for real-time assessment of tissue morphology of 1-2 mm depth. The aims of this study were (1) to compare the histologic and OCT features of excised canine skin and subcutaneous specimens, and (2) to determine the diagnostic accuracy of OCT for surgical margin evaluation. The authors hypothesized that OCT imaging would correlate well with histopathology and that OCT would be sensitive for detection of incomplete margins. Eighty dogs were prospectively enrolled. Tumours were excised, and the surgical margins were imaged using a spectral domain OCT system. The tumour type and completeness of excision were determined by histopathology. Nine blinded observers received training in OCT image interpretation and were then given a set of OCT images and videos. The observers assigned each image/video a grade from 1 (no tumour) to 4 (tumour) and the results were compared to histopathology. The overall median sensitivity and specificity of OCT imaging for detection of incomplete margins were 86.7% and 84.6%, respectively. A potential limitation is that observers had varied experience with OCT image interpretation, ranging from no prior experience to participating in a previous OCT project. OCT is sensitive for detection of incomplete margins and could be a promising real-time surgical margin imaging modality. Further study is needed to evaluate intraoperative applications of OCT and its impact on tumour recurrence and long-term outcome.

Early spatial and temporal events of human T-lymphotropic virus type 1 spread following blood-borne transmission in a rabbit model of infection.

Human T-lymphotropic virus type 1 (HTLV-1) infection causes adult T-cell leukemia/lymphoma (ATL) and is associated with a variety of lymphocyte-mediated disorders. HTLV-1 transmission occurs by transmission of infected cells via breast-feeding by infected mothers, sexual intercourse, and contaminated blood products. The route of exposure and early virus replication events are believed to be key determinants of virus-associated spread, antiviral immune responses, and ultimately disease outcomes. The lack of knowledge of early events of HTLV-1 spread following blood-borne transmission of the virus in vivo hinders a more complete understanding of the immunopathogenesis of HTLV-1 infections. Herein, we have used an established animal model of HTLV-1 infection to study early spatial and temporal events of the viral infection. Twelve-week-old rabbits were injected intravenously with cell-associated HTLV-1 (ACH-transformed R49). Blood and tissues were collected at defined intervals throughout the study to test the early spread of the infection. Antibody and hematologic responses were monitored throughout the infection. HTLV-1 intracellular Tax and soluble p19 matrix were tested from ex vivo cultured lymphocytes. Proviral copy numbers were measured by real-time PCR from blood and tissue mononuclear leukocytes. Our data indicate that intravenous infection with cell-associated HTLV-1 targets lymphocytes located in both primary lymphoid and gut-associated lymphoid compartments. A transient lymphocytosis that correlated with peak virus detection parameters was observed by 1 week postinfection before returning to baseline levels. Our data support emerging evidence that HTLV-1 promotes lymphocyte proliferation preceding early viral spread in lymphoid compartments to establish and maintain persistent infection.

Concurrent Clostridial Enteritis and Oviductal Adenocarcinoma with Carcinomatosis in an Adult Alpaca (Vicugna pacos).

An adult alpaca (Vicugna pacos) with a history of colic and anorexia was euthanized because of failure to respond to treatment. Macroscopically, pale-tan, multifocal to coalescing, firm nodules and plaques markedly expanded the omentum, mesentery and the parietal and visceral peritoneum of multiple abdominal organs, especially the right oviduct and associated mesosalpinx. Abundant dark-red watery digesta were present in the duodenum and jejunum. Histological evaluation of the right oviduct, abdominal visceral nodules and plaques and mesenteric lymph nodes revealed transmural expansion and replacement by an epithelial malignant neoplasm, comprised of tubules and acini of ciliated columnar cells supported by abundant fibrous connective tissue. Both ovaries were histologically normal. On the basis of the ciliated morphology of the neoplastic cells, the focus on the proximal reproductive tract and the unremarkable ovaries, a reproductive tubal adenocarcinoma with carcinomatosis was diagnosed, with both the endometrium and oviduct considered as the tissues of origin. The prominent ciliated morphology of the neoplastic cells and the classification of human fallopian tube (oviduct) neoplasia lead us to propose oviductal adenocarcinoma with widespread carcinomatosis as the definitive diagnosis. The lamina propria of the small intestine was infiltrated segmentally by lymphocytes, plasma cells and neutrophils, and Clostridium perfringens with beta2 toxin production was identified by polymerase chain reaction in the small intestinal contents. To our knowledge, this is the first report of these two distinct diseases in an alpaca.

Pathology in Practice.

In collaboration with the American College of Veterinary Pathologists.