Monocyte chemoattractant protein-1 is critical for monocyte recruitment to the lungs in response to bacterial infection. MCP-1 is also essential for protective neutrophil recruitment to the lungs during Escherichia coli and Klebsiella pneumoniae infection. Staphylococcus aureus pneumonia, specifically strain USA300, carries a high morbidity and mortality rate and is an important pathogen in hospital/ventilator and community acquired pneumonia. In the current study, we investigated the role of MCP-1 in pulmonary innate immunity to S. aureus in C57Bl/6, MCP-1-/- and MCP-1 AB blocked mice. As compared to C57Bl/6, MCP-1-/- mice showed increased concentrations of neutrophils in the airways and lung parenchyma as assessed by nucleated cell concentrations in BALF, myeloperoxidase activity (MPO) in lung tissue, and lung histopathology, and increased concentrations of the pro-inflammatory cytokines TNF-α and IL-6. However, this increase in inflammatory cytokines and augmented neutrophilic response did not correlate with increased bacterial clearance, as determined by CFUs from BALF, lung, liver and spleen. MCP-1 AB blocked mice trended towards higher BALF nucleated cell counts and MPO activity in lung tissue, but were not significantly different from negative controls. In conclusion, MCP-1 appears to be differentially regulated during bacterial pneumonia, and in an S. aureus model, MCP-1-/- mice have moderately enhanced neutrophilic inflammation which does not improve bacterial clearance.

Unilateral arytenoid lateralization is a commonly performed surgical treatment for laryngeal paralysis in dogs. It involves fixing the moveable arytenoid cartilage to the thyroid (TAL) or cricoid (CAL) cartilage or both (CTAL). This increases the area of the rima glottidis (RGA), to allow reduced airway pressure and laryngeal resistance in vitro and ameliorates clinical signs in vivo. It may also increase the patients predisposition for aspiration pneumonia, which occurs in around 20% of clinical patients. No surgical technique has been correlated with clinical outcome or risk of aspiration pneumonia. Objective analysis of the effects of surgery on the three dimensional structure of the larynx has not been performed. Non-invasive assessment and standardization or classification of arytenoid lateralization techniques would allow more effective prospective clinical trials to identify prognostic factors for outcome and complications. Eight cadaver larynges were secured to radiolucent materials for Computed Tomography (CT) before and after TAL, CAL and CTAL with sutures tensioned to 100g or 500g. Multiple measurements were taken from CT 3D reconstructions of the larynx to assess arytenoid displacement in three separate planes. No significant changes were found for any CT measure except the distance between the arytenoid and thyroid wing (ATW). CTAL at 500g and TAL at 500g showed significantly smaller ATW compared to CAL at 100g suggesting that a high tension TAL or CTAL causes the most lateralization of the arytenoid. CAL may allow reduction in airway pressure without excessive lateralization of the arytenoid. ATW is a candidate for a marker of lateralization of UAL procedures, which could be implemented in future prospective clinical studies. Sequential tensioning and loosening of the suture had no significant effect on any measured parameter validating the use of larynges in sequential measurements.

ABSTRACT Objectives - To compare the osteointegration of plasma sprayed hydroxyapatite (HA) coated and uncoated 5.5 mm cortical screws in equine third metacarpal (MC3) bones in combination with a 4.5mm broad dynamic compression plate (DCP). Study design - In vivo study. Animals 6 Adult Thoroughbred horses. Methods For each horse, four HA coated screws were placed unicortically through a 4.5mm broad DCP in the dorsal cortex of a randomly chosen MC3 bone, with 4 uncoated screws placed in an identical manner in the contralateral MC3 bone. All screws were tightened to a torque of 5.4 N-m. Extraction torques were recorded for the screws when removed after 12 weeks. The mean extraction torques for HA coated and uncoated screws were compared to insertion torque using a paired ttest with the statistical significance set at p < 0.05. Results Mean extraction torque of the HA coated screws was significantly (p <0.0002) greater than 5.4 N-m. The mean extraction torque of the uncoated screws was significantly (p < 0.0001) less than 5.4 N-m. The mean extraction torque for the HA coated screws were significantly (p < 0.0001) greater than that of the uncoated screws. Conclusion - The results suggest that osteointegration was occurring for the HA coated screws. The results also suggest that osteointegration did not take place during the 12 weeks period for the uncoated screws. Clinical Relevance - The use of plasma sprayed HA coated screws may provide a means of improving the stability of internal fixation of an equine long bone fractures during the entire healing period by promoting osteointegration.

Arrhythmogenic cardiomyopathy (AC), also known as arrhythmogenic right ventricular cardiomyopathy (ARVC), is a disease characterized by fatty or fibro-fatty myocardial replacement, predominantly in the right ventricle and to a lower extent the left ventricle. It is recognized as a disease affecting the cardiac intercalated disc. Clinically, it is associated with ventricular arrhythmias, although atrial arrhythmias and atrial histopathological changes characteristic of AC have occasionally been reported. The full extent of atrial involvement in AC has not been investigated. Therefore, we aimed to apply histopathology, immunochemical detection, immunolocalization and transmission electron microscopy (TEM) techniques to characterize the distribution of desmosomal and gap junction proteins at the intercalated disc in the atria of boxers with AC. We hypothesized that histological changes consistent with AC and alterations to the intercalated disc proteins are present in the atria of boxer dogs with AC. The hearts from 14 control and 13 boxers with confirmed AC were studied. Right and left atrial sections from 11 boxers were examined by immunofluorescence. Samples from 10 boxers were used for Western blot analysis. The intercalated disc proteins investigated were connexin 43 (Cx43), connexin 45, connexin 40, plakoglobin, plakophilin-2, desmoplakin, and cadherin. Transmission electron microscopy was performed on the right and left atrial sections of 2 boxers and 2 controls. Western blot band relative density indicated a significant decrease of Cx43 in the right atrium of affected boxers compared to controls. There was no difference between controls and boxers for the other proteins investigated. Immunofluorescence analysis showed that the number of Cx43 signals and the signal intensity for plakoglobin was decreased in the left and right atrium of affected boxers. Transmission electron microscopy suggested disruption of the intercalated disc in affected boxers. In conclusion, these results indicate the alteration of intercalated disc proteins in the atrial myocardium of boxers, showing atrial involvement in addition to the ventricles. These findings support the use of the broader term of AC rather than ARVC to describe this disease. The decrease in the amount of Cx43 in conjunction with the histological changes could represent the substrate for the atrial arrhythmias associated with AC.

The objectives of this study were to determine what effects iodixanol would have on total and progressive motility, plasma membrane integrity (viability), acrosome integrity and DNA structure when present during cryopreservation of equine spermatozoa,. We hypothesized that the addition of iodixanol would improve post-thaw values for measured parameters. Ejaculates from six stallions were collected, centrifuged at 900 x g for ten minutes to remove supernatant, and suspended to 200 x 106 cells/ml with 0%, 2.5% and 5% iodixanol in an egg-yolk based extender and cryopreserved. Before and after cryopreservation sperm motility was assessed by computer assisted semen analysis, and samples were stained with SYBR-14/propidium iodide (PI) for viability, with PI/fluorescent isothiocynate-PNA (Arachis Hypogaea) for acrosome integrity and assessed by flow cytometry. Sperm DNA was evaluated using the sperm chromatin structure assay test and assessed by flow cytometry. The mean (± S.E.) percentage pre- and post-thaw total motility, progressive motility, viability, acrosome reactivity, COMPát and MEANát were analyzed using Shapiro-Wilk test to evaluate if data followed a normal distribution. When results followed a normal distribution an ANOVA was performed and where a significant interaction of treatment was observed (p=0.05), a Tukey-Kramer post-hoc test was applied. If results did not follow a normal distribution, a binomial logistical regression was performed. The 5% post-thaw treatment group showed increased viability and decreased DNA damage (p<0.001). Although the 0% group showed greater total and progressive motility than the 2.5% group, it was not greater than the 5% group. The 5% post-thaw treatment group had significantly more (p<0.001) non-reacted and damaged acrosomes than both the 0% and 2.5% groups. These findings suggest that the presence of iodixanol during cryopreservation may have a beneficial effect by protecting plasma membrane and sperm DNA, but the exact mechanism of action is unknown.

Atherosclerosis is a degenerative and inflammatory vascular disease characterized by the accumulation of inflammatory cells, lipids, calcium, and formation of large fibrofatty lesions within the intima of arteries resulting in the disorganization of the arterial wall and stenosis of the lumen. Despite the importance of atherosclerosis in psittacine cardiology, there are few pathologic, clinical, and experimental investigations in psittaciformes. In order to expand the knowledge on psittacine atherosclerosis and provide fundamental observational information for future research, a series of studies was conducted on psittaciformes: 1) psittacine atherosclerotic lesions were characterized and categorized based on histopathology, histochemistry, transmission (TEM), and scanning electron microscopy (SEM) of 63 arterial samples, 2) the prevalence of clinically significant atherosclerotic lesions and the influence of several epidemiological variables were investigated in a multi-center case-control study on 7683 psittaciformes, 3) a diet-induced experimental model of atherosclerosis was developed and characterized in Quaker parrots (Myiopsitta monachus), and 4) a computed-tomography angiographic (CTA) protocol was developed and standardized to image the arterial lumen in Hispaniolan Amazon parrots (Amazona ventralis). Seven lesion types could be described in psittaciformes, which were similar to the human classification system. Digital image analysis, TEM, and SEM helped to further describe the lesions and refine the classification system. Atherosclerosis prevalence significantly increased with age, female sex, and the genera Psittacus, Amazona, and Nymphicus. Mild associations with reproductive, hepatic diseases, and myocardial fibrosis were also evidenced. Experimental induction of atherosclerosis with dietary 1% cholesterol lead to significant lesions within 2 months in Quaker parrots. An increase in arterial and plasma cholesterol and LDL was also documented. Reference limits for arterial luminal diameter of Hispaniolan Amazon parrots were determined by CTA and measurements revealed high intraobserver and interobserver agreement. In conclusion, psittacine atherosclerotic lesions displayed distinctive features that allowed the development of an effective classification system. The prevalence of advanced lesions (type IV-VI) was associated with several risk factors: age, female sex, and three psittacine genera. The Quaker parrot was found to be a suitable experimental model for psittacine atherosclerosis and dyslipidemia. Finally CTA was determined to be safe, reliable, and of potential diagnostic value in parrots for diagnosing stenotic atherosclerotic lesions.

Urokinase (uPA) and urokinase receptor (uPAR) are present in the urinary tract of people, mice, rats and cows. The presence of urokinase and urokinase receptor in the urinary tract of dogs has not been documented. Documenting the presence of uPA and uPAR in the urinary tract of healthy dogs will help determine the role these proteins play in pathology of the urinary tract in further research. Urine was collected from fifty-four healthy dogs. A fluorescence assay was developed using the fluorogenic substrate Z-Gly-Gly-Arg-AMC, HCl. This assay documented presence of active uPA-like protein in concentrated urine. A direct sandwich ELISA assay was developed using a mouse anti-mouse primary antibody and a biotin labeled rabbit anti-human secondary antibody. This ELISA documented presence of active and inactive uPA-like protein and measured concentration of uPA-like protein in concentrated urine. Tissues from the urinary tract of eleven normal dogs (four intact females, five intact males and two castrated males) were collected from kidney, ureter, urinary bladder, urethra, prostate and testicle. SDS-PAGE/Western blot analysis using mouse anti-mouse, mouse anti-human and rabbit anti-human uPA antibodies and a mouse anti-human uPAR antibody were used to identify uPA-like and uPAR-like protein on the basis of molecular weight and antigen-antibody reactions. Immunoprecipitation was employed to enhance identification uPA-like and uPAR-like protein using mouse anti-mouse, mouse anti-human and rabbit anti-human uPA antibodies and a mouse anti-human uPAR antibody. Immunohistochemistry was utilized to identify staining in specific cell types within the urinary tract. The uPA antibodies used were directed against human and mouse urokinase. The uPAR antibody used was directed against human urokinase receptor. A urokinase-like protein is present in urine from healthy dogs in small but measurable quantities. Urokinase-like and urokinase receptor-like protein are present in the urinary tract of the healthy dog. This distribution is similar to that identified in people. The role of urokinase-like and urokinase receptor-like protein in the urinary tract of the normal dog is yet to be defined.

Salmonella is an important intestinal pathogen in horses capable of infecting populations without demonstrating clinical illness. This study was performed to determine the prevalence of Salmonella fecal shedding among racehorses in Louisiana. Three serial fecal samples were collected from 429 Thoroughbred horses housed at four racetracks. Feces were tested for Salmonella by microbiologic culture with selective primary enrichment and delayed secondary enrichment (DSE). Samples were also evaluated for the presence of Salmonella by polymerase chain reaction (PCR) using genus-specific oligonucleotide primers. A total of 7 (1.6%) horses were positive for Salmonella by either primary bacterial culture or DSE and an additional 2 horses (0.5%) were positive for Salmonella by PCR. The combined prevalence of Salmonella fecal shedding from among all the horses in this study was 2.1%. The results of this study suggest that the prevalence of fecal shedding of Salmonella among racehorses in Louisiana is low.

Effects of carprofen on colon of dog have not been investigated. Objectives 1) Measure conductance and permeability to mannitol of transverse, proximal descending and distal descending colonic mucosa of dog. 2) Measure conductance and permeability to mannitol of colonic mucosa of dog in presence of carprofen. Design In vitro experimental - nested, randomized block design Animals Colonic mucosa from 6 (objective 1) and 7 (objective 2) mature mixed-breed dogs. Methods Objective 1) Control - Three sections of mucosa from each region of colon were mounted in Ussing chamber units. Conductance was calculated every 15 min for 240 min. Flux of mannitol was calculated for three periods of one hour. Objective 2) Carprofen - Methods based on results for objective 1. Sections of mucosa were prepared as in objective 1. Carprofen (400μg/ml) was added to bathing solution. Data for conductance and flux of mannitol was obtained as in objective 1. Histologic examination of all sections was performed after experiment. For both objectives, conductance was graphed against time for each chamber and area under each curve calculated. Conductance*time, flux of mannitol and frequency distribution of histologic categories were used for analysis. Results Objective 1) Mean +/- SEM conductance*time transverse colonic mucosa was higher than proximal and distal descending. Mean +/- SEM flux of mannitol increased from period 1 to period 3 for transverse colonic mucosa. Objective 2) Data from objective 1 was used as control for objective 2. Mean +/- SEM conductance*time carprofen group was higher than control group for all regions of colon. For carprofen group, mean +/- SEM flux of mannitol increased from period 1 to period 2 and from period 2 to period 3 for all regions of colon. There was higher proportion of sections with severe sloughing of cells and erosions involving more than 10% of epithelium in carprofen group compared to control. Conclusion Carprofen increases in vitro conductance and permeability to mannitol and causes sloughing of cells and erosions of colonic mucosa of dog which suggests compromise of integrity and loss of barrier function.

ABSTRACT In 1999, there were reports of a new type of lesion in the hides of captive reared alligators from Florida. Similar lesions were first reported from alligator hides in Louisiana in 2001; however, it wasnt until 2002 that small epizootics became apparent. In 2002, the Louisiana Department of Wildlife and Fisheries began a collaborative effort with the Louisiana State University School of Veterinary Medicine (LSU SVM) to help elucidate the etiology of PIX disease, later renamed Lymphohistiocytic Proliferative Syndrome of Alligators (LPSA). Preliminary work concluded that LPSA was a systemic disease affecting multiple tissues. Based on the results of this preliminary study, particularly the histopathologic evaluation of LPSA tissues, a viral etiology was established as the top differential for LPSA. Further work revealed that LPSA positive alligators were 476 (95% CI: 79.6, 2845.2) times more likely to be seropositive for WNV than LPSA negative alligators. At that point it was also becoming clear that the occurrence of LPSA matched the occurrence of WNV in alligator farms. Another project was performed to further elucidate the association between WNV and LPSA based on results of WNV serology, WNV RT-PCR, and histopathologic evaluation of animals with (treatment) and without (control) LPSA lesions. Results from this study revealed that in the treatment group, 97.5% (95%CI: 92.7-102.3 %) of the LPSA skin lesions (TxA) were positive for WNV via RT-PCR. Of the skins within the treatment group that had no LPSA lesions (TxB), 8% (95%CI: 0-16.9%) were positive for WNV. In the control group, all of the skin samples (CxS) were negative for WNV. All alligators in TxA were significantly (p=0.07^-20) more likely to have RT-PCR WNV positive skin than those in CxS, and TxB (p=0.08^-16). There was no significant difference in the recovery of WNV from the skins of alligators from TxB and CxS (p=0.24). The results of this work support the theory that LPSA is a cutaneous manifestation of chronic WNV exposure/infection in captive reared alligators. Therefore the epidemiology of LPSA follows the epidemiology of WNV and prevention, surveillance and control methods used for WNV should effectively decrease the occurrence of LPSA.