Diarrhoea in growing-finishing pigs is a common problem of commercial pig farms. Among many causative factors, porcine circovirus type 2 (PCV2) is one considered an important pathogen in modern pig production. The aim of the study was to verify if PCV2 was responsible for antibiotic non-responsive diarrhoea and wasting in pigs. A total of 13 dead pigs aged between 12 and 15 weeks from three Polish farms with persistent herd symptoms suggestive of PCV2 infection were provided for evaluation. Sections of lymph nodes and intestines were analysed by in situ hybridization (ISH) for PCV2 and histopathological examination. Faeces and intestinal scrapings were tested for Lawsonia intracellularis and Brachyspira hyodysenteriae by real-time PCR and for parasitic infection by flotation and decantation. ISH and histopathological examination showed that all pigs were PCV2 systemic disease negative. Swine dysentery was confirmed by real-time PCR on two farms, and proliferative enteropathy on one farm. In histological examinations, erosions of the caecal and colonic mucosa were found, together with cysts and trophozoites of Balantidium coli. The protozoa were present in the intestinal lumen and mucosa. B. coli cysts were identified in faeces from all examined pigs. These results suggest that monitoring of B. coli infections should be an additional measure of control and prevention of gastrointestinal tract disorders in modern swine husbandry.

The aim of the study was to demonstrate a link between uncomplicated Babesia canis infection in dogs and blood concentrations of zinc and copper and erythrocytic antioxidant defence – activities of glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT). The study was based on 15 naturally occurring cases of canine babesiosis with anorexia, pyrexia, depression, pale mucous membrane, splenomegaly and dark red urine. Microscopic examination of Giemsa-stained peripheral blood smears and the results of PCR confirmed B. canis infection. Seven apparently healthy dogs brought in for either a check-up or vaccination were used for comparison. The levels of the erythrocytic antioxidant enzymes - SOD and CAT - were significantly higher in the infected dogs than in cytologically negative dogs. The levels of blood micronutrients were significantly lower in the infected dogs (0.478 μg of zinc per mL vs 1.241 μg/mL and 0.722 μg of copper per mL vs 1.392 μg/mL). Oxidative stress can be posited as one of the mechanisms leading to anaemia in dogs with babesiosis, and therefore antioxidant biomarker and copper and zinc concentrations could be used as indicators of disease severity and prognostic markers.

The aim of this study was to evaluate the occurrence of Shiga toxin (stx)-producing Escherichia coli (STEC) in diarrheic newborn calves, as well as the resistance profile of this microorganism against antimicrobials routinely used in veterinary therapy. The antimicrobial profile of Eugenia uniflora against E. coli clinical isolates was also analyzed. Specimens from the recto-anal junction mucosa were investigated by using chromogenic medium and identification of E. coli was done using microbiological methods (Gram staining, indole test, methyl red test, Voges-Proskauer test, citrate test, urease test, and hydrogen sulfide test). The stx1 and stx2 genes corresponding to the STEC pathotype were evaluated by using polymerase chain reaction and electrophoresis. The susceptibility profile to antimicrobial agents commonly used in veterinary therapeutic practice and the antimicrobial effect of lyophilized hydroalcoholic extract of E. uniflora L. leaves against E. coli clinical isolates were evaluated by disk diffusion and microdilution methods. Shiga toxin-positive E. coli was identified in 45% of diarrheic newborn calves (stx1 = 23.2%, stx2 = 4.0%, stx1 + stx2 = 18.2%). The frequency of stx-positive E. coli in the bacterial population was equal to 17.0% (168/990 clinical isolates): 97 (9.8%) stx1-positive E. coli, 12 (1.2%) stx2-positive E. coli, and 59 (6.0%) stx1 + stx2-positive E. coli isolates. All stx-positive E. coli analyzed showed resistance to multiple drugs, that is, from 4 to 10 antimicrobials per clinical isolate (streptomycin, tetracycline, cephalothin, ampicillin, sulfamethoxazole + trimethoprim, nitrofurantoin and nalidixic acid, ciprofloxacin, gentamicin, and chloramphenicol). Effective management measures should be implemented, including clinical and laboratory monitoring, in order to promote animal and worker health and welfare, prevent and control the spread of diseases, and ensure effective treatment of infectious diseases. The E. uniflora L. leaves showed inhibition of microbial growth based on the diameter of halos, ranging from 7.9 to 8.0 mm and 9.9 to 10.1 mm for concentrations of 50 and 150 mg/mL, respectively. This plant displayed bacteriostatic action and a minimum inhibitory concentration of 12.5 mg/mL for all clinical isolates. Its clinical or synergistic effects with antimicrobial agents must be determined from clinical and preclinical trials.

OBJECTIVE To compare the efficacy and duration of desensitization of oral structures following injection of various volumes of lidocaine-bupivacaine via an infraorbital approach in dogs. ANIMALS 6 healthy adult hound-type dogs. PROCEDURES In a randomized crossover study, each dog received 1, 2, and 3 mL of a 2% lidocaine-0.5% bupivacaine mixture (50:50 vol/vol) injected within and near the caudal aspect of the infraorbital canal with a 14-day washout period between treatments. Dogs were anesthetized, and each treatment was administered through a 22-gauge, 4.5-cm-long catheter, which was fully inserted through and then withdrawn 2 cm to the caudal aspect of the infraorbital canal. The reflex-evoked motor potential was measured for the maxillary canine tooth (MC), fourth premolar tooth (MPM4), second molar tooth (MM2), and hard palate mucosa ipsilateral to the injected treatment and for the contralateral MC (control) at predetermined times before and for 6 hours after treatment administration or until the block was no longer effective. For each oral structure, the proportion of dogs with desensitization (efficacy) and time to onset and duration of desensitization were compared among the 3 treatments (injectate volumes). RESULTS Treatment was not associated with efficacy, time to onset, or duration of desensitization. Regardless of treatment, MC and MPM4 were more frequently desensitized and mean durations of desensitization for MC and MPM4 were longer, compared with those for MM2 and the hard palate. CONCLUSIONS AND CLINICAL RELEVANCE the volume of local anesthetic used for an infraorbital nerve block had no effect on block efficacy or duration.

OBJECTIVE To determine usefulness of skin turgor and capillary refill time (CRT) for predicting changes in hydration status of working dogs after a 15-minute exercise period. ANIMALS 9 exercise-conditioned working dogs between 8 and 108 months of age. PROCEDURES Skin tent time (SkTT; time for tented skin on the forehead to return to an anatomically normal position) and CRT (time for occluded mucous membrane capillary vessels to return to the color visible before occlusion) were measured on dogs in a field setting and by video review. Body weight (BW), SkTT, CRT, and core body temperature were measured before and after a 15-minute exercise period. Exercise challenge was performed on days 1 and 8. RESULTS Time (day 1 vs day 8) did not significantly affect results; therefore, data were pooled for the 2 trial days. Mean ± SE BW decreased (but not significantly) by 0.83 ± 0.27% after exercise. The SkTT increased significantly (both field setting and video review) after exercise. Correlation between SkTT results for the field setting and video review (r = 0.68) was significant. The CRT decreased (but not significantly) after exercise. CONCLUSIONS AND CLINICAL RELEVANCE Dogs became mildly dehydrated (mean BW loss, 0.83%) during a 15-minute exercise period, and the mild dehydration was evident as a visually detectable change in skin turgor. Monitoring the SkTT appeared to be a useful strategy for predicting small shifts in hydration status of dogs during exercise. The CRT decreased and was not a significant predictor of a change in hydration status.

The objectives of the study were to: i) determine baseline microvascular perfusion indices (MPI) and assess their repeatability in healthy horses under general anesthesia, and ii) compare the MPIs of 3 microvascular beds (oral mucosa, colonic serosa, and rectal mucosa). Healthy adult horses were anesthetized and sidestream dark field microscopy was used to collect video loops of the oral mucosa, rectal mucosa, and colonic serosa under normotensive conditions without cardiovascular support drugs; videos were later analyzed to produce MPIs. Baseline MPI values were determined for each site, which included the total vessel density (TVD), perfused vessel density (PVD), portion perfused vessels (PPV), and microcirculatory flow index (MFI). Differences in MPIs between microvascular beds were not statistically significant. Repeatability of the measurements varied for each MPI. In particular, the site of sampling had a profound effect on the repeatability of the PPV measurements and should be considered in future studies.

The purpose of the study was to compare the conductance and mannitol permeability of canine colonic mucosa in response to carprofen or 2,4-dinitrophenol (DNP) with or without tempol pretreatment. Ten colonic mucosa sections per dog were mounted in Ussing chambers. Treatments were done in duplicate. Mucosa was exposed to carprofen (200 μg/mL) or DNP (0.25 mM), both with and without tempol (1 mM) pretreatment. Conductance was calculated every 15 min for 240 min. Mannitol flux was calculated over 3 consecutive 60-minute periods. Histology or electron microscopy was done after exposure. Conductance over time, mannitol flux, frequency of histologic categories, and electron microscopic changes were analyzed for treatment effects. The mean ± standard deviation (SD) conductance over time for carprofen or DNP-treated colons was not significantly different from control regardless of tempol pretreatment. Period 3 mannitol fluxes for carprofen and DNP-treated colon were not significantly different, but were greater than control. Period 3 mannitol flux for tempol + carprofen was significantly less than tempol + DNP-treated colon. Sloughing of cells and erosions were seen in the mucosa of carprofen-treated colon. Mitochondrial damage was seen more often in carprofen-treated than DNP-treated or control colon. Tempol pretreatment resulted in more ruptured mitochondria in the carprofen-treated colon; however, other mitochondrial changes were not significantly affected by tempol pretreatment in either carprofen or DNP treated colon. Treatment with carprofen or DNP increased the mannitol flux, but pretreatment with tempol mitigated the carprofen effect. It is apparent that structural mitochondrial damage occurs in the canine colonic mucosa after carprofen and DNP exposure.

Objective-To determine whether increasing the viscosity of a standard hemoglobin-based oxygen-carrying solution (HBOC) would offset its associated vasoconstrictive effects and result in improved microvascular perfusion in healthy splenectomized dogs with experimentally induced hemorrhagic shock. Animals-12 male American Foxhounds. Procedures-Each dog underwent anesthesia and splenectomy. Shock was induced by controlled hemorrhage until a mean arterial blood pressure of 40 mm Hg was achieved and maintained for 60 minutes. Dogs were then randomly assigned to receive either a standard or hyperviscous HBOC (6 dogs/group). Sidestream dark-field microscopy was used to assess the effects of shock and HBOC administration on the microcirculation of the buccal mucosa and the jejunal serosa. Video recordings of the microcirculation were collected before shock was induced (baseline) and at intervals up to 180 minutes following HBOC administration. Vascular analysis software was used to compute microcirculatory variables. Results-Compared with baseline findings, hemorrhagic shock resulted in decreases in all microvascular variables in the buccal mucosa and the jejunal serosa. At all time points following HBOC administration, microvascular variables were similar to initial values and no significant differences between treatment groups were detected. At all time points following HBOC administration, blood and plasma viscosities in dogs treated with the hyperviscous solution were significantly higher than values in dogs receiving the standard solution. Conclusions and Clinical Relevance-In splenectomized dogs with experimentally induced hemorrhagic shock, administration of a hyperviscous HBOC did not significantly affect microvascular variables, compared with effects of a standard HBOC. Microcirculatory flow returned to baseline values in both treatment groups, suggesting that marked HBOC-associated vasoconstriction did not occur.

Objective—To assess the microcirculatory effects of IV fluid administration in healthy anesthetized dogs undergoing elective ovariohysterectomy. Animals—49 client-owned dogs. Procedures—Dogs were sedated, and anesthesia was induced with propofol and diazepam and maintained with isoflurane in oxygen. Dogs received lactated Ringer's solution (LRS) IV at rates of 0, 10, or 20 mL/kg/h. Videomicroscopy was used to assess and record effects of LRS administration on microcirculation in the buccal mucosa. Measurements of microcirculatory (total vessel density, proportion of perfused vessels, microcirculatory flow index, and perfused vessel density by vessel size [< 20 μm, ≥ 20 μm, and all diameters]) and other physiologic variables (heart rate, Doppler-measured blood pressure, oxygen saturation as measured by pulse oximetry, capillary refill time, and body temperature) were compared among groups at baseline (immediately after anesthetic induction), 30 and 60 minutes afterward, and overall. Results—Neither the proportion of perfused vessels nor microcirculatory flow index varied among treatment groups at any time point, regardless of vessel size. For vessels < 20 μm in diameter and for all vessels combined, total and perfused vessel density were similar among groups. For vessels ≥ 20 μm in diameter, total vessel density was significantly greater in the 20 mL/kg/h group than in other groups, and perfused vessel density was significantly greater in the 20 mL/kg/h group than in the 0 mL/kg/h group, when all time points were considered. Other physiologic variables were similar among groups. Conclusions and Clinical Relevance—Total and perfused vessel density of vessels ≥ 20 μm in diameter (mostly venules) were greatest in dogs that received 20 mL of LRS/kg/h. Further research is required to evaluate clinical importance of these findings.

Objective: To determine effects of leukotriene (LT) C4 on ion transport across equine tracheal epithelium. Sample: Tracheal epithelium from cadavers of 24 horses considered free of respiratory tract disease. Procedures: Mucosae were mounted into Ussing chambers, and short-circuit current (Isc) was monitored over time. Effects of LTC4 were examined for various conditions, including addition of amiloride (10μM) to the mucosal bath solution, addition of bumetanide (10μM) to the serosal bath solution, addition of barium (1mM) to the serosal bath solution, and substitution of gluconate for chloride and HEPES for bicarbonate in bath solutions. Electrolyte transport was assessed via 22Na and 36Cl isotope fluxes. Results: Addition of LTC4 (50nM) to the serosal bath solution caused an increase in Isc for basal conditions and a larger increase after pretreatment with amiloride. The increase was negated in part by the addition of bumetanide to the serosal bath solution and further reduced by substitution of HEPES for bicarbonate in bath solutions. Remaining current was reduced to values less than those before treatment with LTC4 by the addition of barium to the serosal solution. There was a small increase in Isc after the addition of amiloride and substitution of gluconate for chloride. Radioisotope flux indicated that addition of LTC4 to the serosal bath solution increased chloride secretion and reduced sodium absorption. Conclusions and Clinical Relevance: LTC4 stimulated chloride secretion through a predominately bumetanide-sensitive pathway, with a smaller contribution from a bicarbonate-dependent pathway. Thus, LTC4 appears to be a potential mediator of airway hypersecretion in horses.