Peritoneal fluid values from healthy foals

Peritoneal fluid was analysed from 17 foals, aged 13 to 134 days with a mean age of 68 days. Cytologically, the peritoneal fluid was characterised by a mean total cell count of 0.45 x 10(9)/litre (range 0.06 to 1.42 x 10(9)/litre), rare eosinophils, rare cytophagia and variable percentages of neutrophils and mononuclear cells. These data indicate that peritoneal fluid nucleated cell counts over 1.50 x 10(9)/litre in the foal should be interpreted as elevated. Biochemical evaluation revealed a mean biuret protein level of 12 g/litre, mean refractive index protein level of 16 g/litre and urea nitrogen concentration of 1.96 mmol/litre. There was no correlation between the foals' white blood cell and peritoneal fluid nucleated cell counts. Results of this study indicate that adult horse reference values for evaluation of peritoneal fluid are of questionable validity for foals. Diagnostically, the most important observation was that maximum peritoneal fluid nucleated cell counts in healthy foals were much lower than reported maximal reference values for adult horses (1.5 x 10(9)/litre versus 5.0 x 10(9)/litre or 10.0 x 10(9)/litre).     

Using urea dilution to standardise components of pleural and bronchoalveolar lavage fluids in the dog

AIM: To develop a technique to estimate the volume of epithelial lining fluid (ELF) obtained during bronchoalveolar lavage (BAL) and pleural lavage (PL) in the dog, using the urea dilution method. METHODS: BAL and PL fluids were obtained by saline lavage of pulmonary and pleural cavities of nine clinically healthy mixed-breed dogs immediately after euthanasia. Cell counts in the BAL and PL fluids were measured using standard techniques. The concentration of ELF in each lavage fluid was calculated from the relative concentration of urea in plasma and in each type of lavage fluid. Cell counts in ELF were then calculated. RESULTS: There were substantially higher cell counts in ELF compared to BAL or PF fluid. However, nucleated cell counts in ELF could not be predicted from cell counts in BAL or PL fluid. CONCLUSIONS AND CLINICAL RELEVANCE: These results suggest that accurate assessment of cellular or non-cellular components in lavage fluids should include a calculation of the proportion of ELF recovered, using a method such as urea dilution.     

Using urea dilution to standardise components of pleural and bronchoalveolar lavage fluids in the dog

AIM: To develop a technique to estimate the volume of epithelial lining fluid (ELF) obtained during bronchoalveolar lavage (BAL) and pleural lavage (PL) in the dog, using the urea dilution method.

METHODS: BAL and PL fluids were obtained by saline lavage of pulmonary and pleural cavities of nine clinically healthy mixed-breed dogs immediately after euthanasia. Cell counts in the BAL and PL fluids were measured using standard techniques. The concentration of ELF in each lavage fluid was calculated from the relative concentration of urea in plasma and in each type of lavage fluid. Cell counts in ELF were then calculated.

RESULTS: There were substantially higher cell counts in ELF compared to BAL or PF fluid. However, nucleated cell counts in ELF could not be predicted from cell counts in BAL or PL fluid.

CONCLUSIONS AND CLINICAL RELEVANCE: These results suggest that accurate assessment of cellular or non-cellular components in lavage fluids should include a calculation of the proportion of ELF recovered, using a method such as urea dilution.     

Using urea dilution to standardise cellular and non-cellular components of pleural and bronchoalveolar lavage (BAL) fluids in the cat

A technique to standardise the analysis of cellular and non-cellular components in epithelial lining fluid (ELF) collected during saline lavage of pulmonary and pleural cavities was developed using the urea dilution method. Bronchoalveolar lavage (BAL) and pleural lavage (PL) fluids were collected from 12 clinically healthy cats. Total and differential cell counts in BAL fluid were within normal ranges for the cat, while cell counts in PL fluid were assumed to be normal based on clinical health during examination, auscultation and lactate dehydrogenase (LDH) activities being comparable with other species. The major clinical implication of this study was that nucleated cell counts within feline ELF could not be predicted from analysis of lavage fluid which suggests that calculation of the proportion of ELF in lavage fluid by the urea dilution method may be necessary to avoid misdiagnosis of health or disease in pulmonary or pleural cavities.     

Plasma and bronchoalveolar fluid concentrations of nitric oxide and localization of nitric oxide synthesis in the lungs of horses with summer pasture-associated obstructive pulmonary disease

OBJECTIVE: To determine concentrations of nitric oxide (NO) in plasma and bronchoalveolar lavage fluid (BALF) and localize nitric oxide synthesis in the lungs of horses with summer pasture-associated obstructive pulmonary disease (SPAOPD). ANIMALS: 7 adult horses with SPAOPD and 6 clinically normal adult horses. PROCEDURE: Severity of SPAOPD was determined by use of clinical scores, change in intrapleural pressure (APpl) during tidal breathing, cytologic analysis of BALF, and histologic evaluation of lung specimens obtained during necropsy. Nitric oxide concentrations in plasma, BALF and epithelial lining fluid (ELF) were determined by use of a chemiluminescent method. Inducible nitric oxide synthase (iNOS) and nitrotyrosine (NT) were localized in formalin-fixed lung specimens by use of immunohistochemical staining, and nicotinamide adenine dinucleotide phosphate diaphorase (NADPHd) activity was localized in cryopreserved specimens by use of histochemical staining. RESULTS: Plasma concentration of NO in affected horses was slightly but not significantly greater than concentration in nonaffected horses. Nitric oxide concentrations in BALF or ELF did not differ between groups. Immunoreactivity of iNOS in bronchial epithelial cells of 3 of 5 lung lobes was greater in horses with SPAOPD, compared with nonaffected horses. However, staining for NT and NADPHd activity did not differ between groups. CONCLUSIONS AND CLINICAL RELEVANCE: Expression of iNOS was greater in bronchial epithelial cells of horses with SPAOPD, compared with nonaffected horses, suggesting that NO may play a role in amplifying the inflammatory process in the airways of horses with this disease.     

Comparison of the antioxidant status in tracheal and bronchoalveolar epithelial lining fluids in recurrent airway obstruction

REASONS FOR PERFORMING STUDY: Following a period of airway inflammation the clearance of inflammatory cells along the mucociliary escalator may impose a considerable oxidant load on the trachea. OBJECTIVES: To determine the degree of oxidative stress in tracheal epithelial lining fluid (ELF) in comparison to that present in peripheral airways after an acute exposure to organic dust. METHODS: Tracheal wash fluid and bronchoalveolar lavage fluid (BALF) were collected for cytology and antioxidant analyses from 6 recurrent airway obstruction (RAO)-affected horses and 6 healthy control horses before and after stabling on straw bedding for 24 h. RESULTS: In RAO-affected horses, organic dust exposure resulted in a significant decrease in ascorbic acid concentration in tracheal ELF (P<0.0001), which was greater than the decrease in bronchoalveolar ELF (P = 0.0003). The percentage decrease in tracheal ELF ascorbic acid correlated with the percentage decrease in bronchoalveolar ELF ascorbic acid (r = 0.76; P = 0.004) following exposure. CONCLUSIONS: Acute organic dust exposure results in significant antioxidant depletion in the trachea, which may reflect inflammation and oxidative processes in peripheral airways. POTENTIAL RELEVANCE: Further work is required to evaluate the role of ascorbic acid depletion in the pathogenesis of RAO.     

Effect of repetitive bronchoalveolar lavage on cytologic findings in healthy dogs

OBJECTIVE: To determine reference values for cytologic examination results of bronchoalveolar lavage fluid (BALF) and to investigate effects of repeated lavages on pulmonary health and on results of cytologic examination of BALF in dogs. ANIMALS: 16 healthy adult Beagles. PROCEDURE: All dogs underwent pulmonary lavage to obtain BALF. Eleven dogs were repeatedly lavaged 6 times at 5- to 7-week intervals. Analyses for total and differential cell counts and for viability of cells before and after cell processing were performed. Arterial blood gas analysis before and after bronchoalveolar lavage was used to study the safety of the lavage procedure. Histologic and radiologic examinations were used to study effects of repeated lavages on pulmonary health. RESULTS: Mean (+/- SD) cell count was 104 +/- 69 cells/microl, comprising 75 +/- 7% alveolar macrophages, 13 +/- 6% lymphocytes, 5 +/- 4% neutrophils, 4 +/- 5% eosinophils, 2 +/- 2% mast cells, 0.6 +/- 0.7% epithelial cells, and 0.3 +/- 0.4% plasma cells. Centrifugation of samples and washing of cells caused significant cell loss (59 +/- 13%). Repeated lavages did not cause significant variations in cell counts of BALF or results of arterial blood gas analysis, thoracic radiography, or histologic examination of pulmonary specimens. Only a moderate, although significant, decrease in arterial oxygen content was observed after bronchoalveolar lavage. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis indicated that several lavages performed at 5- to 7-week intervals can safely and reliably be used to study the kinetics of pathologic processes in pulmonary tissues or for evaluation of therapeutic efficacy.     

Time-dependent alterations in gene expression of interleukin-8 in the bronchial epithelium of horses with recurrent airway obstruction

OBJECTIVE: To evaluate time-dependent alterations in gene expression of chemokines in bronchial epithelium of recurrent airway obstruction (RAO)-affected horses and whether alterations resulted from increases in gene expression of interleukin (IL)-17 in cells isolated from bronchoalveolar lavage fluid (BALF). ANIMALS: 8 RAO-susceptible horses and 9 control horses. PROCEDURE: In 2 experiments, both groups of horses were evaluated after being maintained on pasture and after being stabled and fed dusty hay for 1, 14, 35, and 49 days (experiment 1) or 14 and 28 days (experiment 2). In experiment 1, gene expression of IL-8, chemokine (C-X-C motif) ligand 1 (CXCL1), granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte colony-stimulating factor (G-CSF), and Toll-like receptor 4 (TLR4) in epithelium and IL-8, IL-17, and TLR4 in BALF cells was measured. In experiment 2, bronchial biopsy specimens were evaluated for IL-8 immunoreactivity. RESULTS: In RAO-susceptible horses after 14 days of challenge exposure, there was a 3- and 10-fold increase in gene expression of IL-8 for epithelial and BALF cells and an increase in IL-8 immunoreactivity in epithelial cells. Challenge exposure failed to alter gene expression of CXCL1, GM-CSF, G-CSF, and TLR4 in epithelial cells of any horses at any time point. During challenge exposure, gene expression of BALF cell IL-17 was downregulated in control horses (day 1) and upregulated in RAO-affected horses (day 35). CONCLUSIONS AND CLINICAL RELEVANCE: Epithelial-derived IL-8 may promote airway neutrophilia, but the inciting stimulus is unlikely to be IL-17 because upregulation of this gene is subsequent to that of IL-8 in epithelial cells.     

Septic arthritis in 15 standardbred racehorses after intra-articular injection.

Case histories, results of synovial fluid analyses, treatment regimens and outcome are described for 15 adult Standardbred horses with confirmed post-injection septic arthritis. Joint sepsis followed injection of corticosteroids, hyaluronic acid, polysulphated glycosaminoglycan, or local anaesthetic. The median interval from injection to appearance of clinical signs was 2.5 days, and median interval from injection to referral was 9 days. The median initial synovial leucocyte count on admission was 57 x 10(9)/litre, but there was a wide range of values (18-258 x 10(9)/litre). The median synovial neutrophil percentage was 95% (77-99%). All bacterial isolates were Gram-positive cocci, 86% of which were staphylococci. All treated horses (12/15) initially received broad-spectrum parenteral antibiotic therapy, and the articulations of all horses except one were lavaged, either with non-surgical through-and-through techniques only (N = 3), or surgically with arthrotomy (N = 1) or arthroscopy (N = 7). The owners of all treated horses were contacted and racing records were consulted. Eleven of 12 horses returned to racing. Outcome was judged as either satisfactory (3/12) if the horse had returned to racing levels similar to or better than before treatment, or unsatisfactory (9/12) if the horse had poorer performance or could not return to racing. The 3 horses with satisfactory follow-up had been treated with arthroscopy and post-surgical closed suction drainage. The results of bacterial cultures suggest that the initial antimicrobial agents used should be effective against penicillin-resistant staphylococci.     

Respiratory disease markers in porcine bronchoalveolar lavage fluid

In bronchoalveolar lavage fluid (BALF) of pigs originating from different herds bacteria, cells and the antibacterial peptide PR-39 were examined to gain information about the lung health status. In a high health nucleus herd 56% and in low health herds 20-100% of the examined pigs were found positive for potentially pathogenic bacteria. Based on these findings, a novel definition for bacterial respiratory tract disease was established using an 8% cut-off for the relative number of neutrophils in bronchoscopic and a 40% cut-off in transtracheal BALF in combination with the occurrence of potentially pathogenic microorganisms. The antibacterial peptide PR-39 was highly correlated to this definition of respiratory disease. An assessment of the bacteriological respiratory health status appears to be possibly based on the determination of PR-39 concentrations in BALF using different cut-off values according to the lavage method (2.5 nM for bronchoscopic and 5 nM for transtracheal BALF).     

Effect of composition and different fractions of hay dust suspension on inflammation in lungs of heaves-affected horses: MMP-9 and MMP-2 as indicators of tissue destruction

REASONS FOR PERFORMING STUDY: Airway matrix metalloproteinases (MMPs) increase following inhalation of organic dust. The relative contribution of dust components to this elevation is unknown. OBJECTIVE: To identify components of organic dust responsible for elevated MMP levels in equine airways. METHODS: Bronchoalveolar lavage (BALF) from 7 heaves-susceptible horses, collected 6 h following inhalation challenges with saline, 2 different hay dust suspensions (HDS-1 and -2) and soluble and particulate fractions of HDS-1, were analysed for MMP-2 and -9 using SDS-page gelatin zymography. RESULTS: HDS-1 challenge increased BALF proMMP-9 and total MMP-9. HDS-1 fractions, or the particulate fraction with added lipopolysaccharide, increased BALF proMMP-9 and total MMP-9 in combination, but not when inhaled separately. HDS-2 inhalation elevated BALF complex forms, proMMP-9, active MMP-9, total MMP-9 and total MMP-2. CONCLUSIONS: The results suggest synergistic action of soluble and particulate organic dust components. The fact that HDS-1 and HDS-2 had different glucan concentrations supports a role for moulds in the activation of MMP-9. POTENTIAL RELEVANCE: Activation and release of MMPs in response to inhaled moulds are involved in the aetiopathogenesis of heaves. Endotoxin contributes to the synergistic action of the dust components, but the overall MMP response to organic dust inhalation in heaves-susceptible horses largely reflects the mould content of the dust. In the future, inhibition of MMP production and release may offer therapeutic means for treatment and prevention of heaves and recommendations for acceptable dust levels can be given.     

Characterisation of the acute and reversible airway inflammation induced by cadmium chloride inhalation in healthy dogs and evaluation of the effects of salbutamol and prednisolone

The aims of this study were firstly to characterise a model of subclinical and reversible bronchial inflammation induced by cadmium chloride inhalation in healthy dogs and then to examine the effect of prednisolone or salbutamol treatment on the resulting bronchitis. The model characterisation and the effects of treatment were studied using clinical symptoms, haematology, thoracic radiography, bronchoscopy and bronchoalveolar lavage, barometric whole-body plethysmography and histamine broncho-provocation tests. In addition, the activity of matrix metalloproteinases (MMP)-2 and -9 were determined in serum and bronchoalveolar lavage fluid (BALF). Cadmium inhalation induced: (1) a transient bronchial inflammation, dominated by neutrophils; (2) a neutrophilia of the blood that persisted for up to 4 weeks; (3) a transient increased bronchial reactivity, and (4) a significant increase in MMP-9 activity in the BALF. Prednisolone treatment reduced the influx of inflammatory cells into the BALF, but not significantly, had no effect on pulmonary function, and did not reduce of airway hypersensitivity. Salbutamol had almost no effect on any of the parameters investigated.     

Clinical findings,bronchoalveolar lavage fluid cytology and matrix metalloproteinase-2 and -9 in canine pulmonary eosinophilia

We characterized clinical and clinicopathological features, and the involvement of gelatinolytic matrix metalloproteinases (MMP-2 and -9) in canine pulmonary eosinophilia (PE). Study material consisted of 20 PE dogs and 16 healthy beagles. All dogs underwent a similar clinical examination and bronchoalveolar lavage (BAL). Analysis for cell count and differential cell count of BAL fluid (BALF), arterial blood gas analysis before and after BAL, and thoracic radiographs before BAL and after treatment were obtained. Twelve dogs were re-evaluated and six relavaged. MMP-2 and MMP-9 in BALF were analysed by zymography, Western immunoblotting and immunocytochemistry.In the PE dogs, BALF, cell count, number and percentage of eosinophils, and numbers of macrophages, lymphocytes, neutrophils, mast cells and epithelial cells were all significantly elevated. Blood eosinophilia was detected in half of the PE dogs. Three PE dogs had mild hypoxaemia. The BAL procedure had an equal effect on PE and healthy dogs' arterial blood gas values. Bronchointerstitial densities were seen in PE dogs' radiographs. Treatment of PE decreased BALF cell count, eosinophil count and percentage and diminished radiographic changes. Gelatinolytic activity was higher in PE dogs' BALF. BALF macrophages and epithelial cells were the principal sources of the MMP-9.     

Dose responses to inhalation of endotoxin, hay dust suspension and Aspergillus fumigatus extract in horses as measured by levels and activation of matrix metalloproteinase-9

REASONS FOR PERFORMING STUDY: Airway matrix metalloproteinases (MMPs) increase after endotoxin (LPS) exposure, but there are no reports describing dose-dependent increases or activation following exposure. OBJECTIVES: To study matrix metalloproteinase-9 (MMP-9) and -2 (MMP-2) responses in bronchoalveolar lavage fluid (BALF) from heaves-susceptible and control horses following inhalation of hay dust suspension (HDS), LPS and Aspergillus fumigatus extract (AFE). METHODS: Heaves-susceptible (n = 7) and control (n = 6) horses received inhalation challenges with 3 different doses of HDS and LPS. Heaves-susceptible horses (n = 6) also received 3 different doses of AFE and one dose of AFE depleted of endotoxin (AFE-LPS). BALF collected following inhalation challenges was analysed using gelatin zymography. Gelatinolytic bands were identified as complex, pro-MMP-9, active MMP-9, pro-MMP-2 and active MMP-2 based on molecular weights. RESULTS: Each challenge substance induced a dose-dependent elevation in gelatinolytic activity. The dose-dependency was most evident for pro-MMP-9 and total MMP-9 levels in heaves-susceptible horses following LPS challenges. CONCLUSIONS: There is a dose-dependent elevation in MMP-9 in BALF of heaves-susceptible and control horses following inhalation challenge with organic dust and some of its components, elevation being more marked in heaves-susceptible horses. Organic dust components vary in their pro-inflammatory potential. POTENTIAL RELEVANCE: This study supports the role of MMPs in the pathogenesis of heaves and highlights the potential value of protease inhibitors in attenuating the airway inflammatory response to inhaled organic dust.     

Comparison of bronchoalveolar lavage fluid obtained from Mannheimia haemolytica-inoculated calves with and without prior treatment with the selectin inhibitor TBC1269

OBJECTIVES: To determine effects of selectin inhibitor TBC1269 on neutrophil infiltration, and neutrophil-associated injury during pneumonia induced by Mannheimia haemolytica and concentration of antimicrobial anionic peptide (AAP) in bronchoalveolar lavage fluid (BALF) as well as antimicrobial activity of BALF from healthy (control) neonatal calves, neonatal calves with M haemolytica-induced pneumonia, neonatal calves with prior treatment with TBC1269, and adult cattle. ANIMALS: Eighteen 1- to 3-day-old calves and 9 adult cattle. PROCEDURE: Calves were inoculated with M haemolytica or pyrogen-free saline (0.14M NaCl) solution into the right cranial lung lobe, and BALF was collected 2 or 6 hours after inoculation. Thirty minutes before and 2 hours after inoculation, 4 calves received TBC1269. The BALF collected from 9 adult cattle was used for comparison of BALF AAP concentration and antimicrobial activity. Protein concentration and neutrophil differential percentage and degeneration in BALF were determined. An ELISA and killing assay were used to determine BALF AAP concentration and antimicrobial activity, respectively. RESULTS: Total protein concentration was significantly decreased in BALF from calves receiving TBC1269. Similar concentrations of AAP were detected in BALF from all calves, which were 3-fold higher than those in BALF from adult cattle. However, BALF from neonates had little or no anti-M haemolytica activity. CONCLUSIONS AND CLINICAL RELEVANCE: These results suggest that TBC1269 decreases pulmonary tissue injury in neonatal calves infected with M haemolytica. Although AAP is detectable in neonatal BALF at 3 times the concentration detected in adult BALF, neonatal BALF lacks antimicrobial activity for M haemolytica.     

Rush immunotherapy in an experimental model of feline allergic asthma

Specific allergen immunotherapy represents the only curative treatment of allergy. No studies have evaluated its efficacy in feline allergic asthma. We hypothesized that an abbreviated course of immunotherapy (rush immunotherapy, RIT) would blunt eosinophilic airways inflammation in experimental feline asthma induced with Bermuda grass allergen (BGA). The 6-month study included asthmatic-RIT treated cats; asthmatic-no RIT treated cats; and non-asthmatic cats. RIT involved increasing parenteral doses (20-200 microg) of BGA over 2 days. Numbers of eosinophils in bronchoalveolar lavage fluid (BALF), serum and BALF immunoglobulins, lymphocyte blastogenesis assays, and cytokines in blood and BALF were evaluated. BALF eosinophils decreased (P=0.048) only in asthmatic-RIT treated cats (baseline 1.1 x 10(6); Month 6, 2.4 x 10(5)). Serum BGA-specific IgG was higher (P<0.001) at all time points after baseline within the asthmatic-RIT group, and was higher (P<0.001) than asthmatic-no RIT cats at Months 1 and 3. No differences (P=0.133) in BGA-specific IgE levels over time were noted among asthmatic-RIT cats, but this group had lower IgE levels (P<0.001) levels than asthmatic no-RIT cats at Months 3 and 6. Differences in BGA-specific IgA levels over time and between the two groups did not reach the traditional level of significance. The mean BGA stimulation index in the asthmatic-RIT cats was biologically insignificant at 6 months, reflecting BGA-specific lymphocyte hypoproliferation. Preliminary results of cytokine profiles were not significantly different; however, BAL cytokine profiles favoring a Th2 response prior to RIT shifted to increased IFN-g and IL-10 thereafter. RIT dampens eosinophilic airways inflammation in cats with experimental asthma. The mechanism of RIT may involve changes in allergen-specific immunoglobulins, induction of hyporesponsive lymphocytes, or alteration of cytokine profiles.     

Cytokine expression by pulmonary leukocytes from calves challenged with wild-type and leukotoxin-deficient Mannheimia haemolytica

The objective of this study was to assess the role of leukotoxin (LKT) in modulating the pulmonary cytokine response of calves challenged with Mannheimia haemolytica. Thirty-six calves, seronegative to LKT and M. haemolytica whole cell antigen were divided into three groups (I, II and III). Calves in groups I and II were challenged by the intra-bronchial route with 25 mL of phosphate buffered saline (PBS) containing 0.44×10(9) cfu/mL of LKT deficient (lkt(-)) and 25 mL of PBS containing 0.31×10(9) cfu/mL of wild-type (wt) M. haemolytica serotype 1, respectively. Group III calves were challenged intra-bronchially with 25 mL of sterile PBS. Leukocytes were collected from broncho-alveolar lavage fluid (BALF) 4 days before and at 1, 3, and 6 days post-inoculation (p.i.). Expression of the following cytokines in the recovered leukocytes was measured using real-time PCR: interleukin (IL)-1β, -8, -10, -12 (p40) and TNF-α. The amount of TNF-α produced was also quantified by ELISA. Although a statistically significant difference in the expression of these cytokines was not observed between groups challenged with the wt and lkt(-) strains, the wt infected group (II) did exhibit higher mean clinical scores. Overall, there was considerable variation in the composition of the BALF between the groups and by day 7 p.i., both lkt(-)- and wt-challenged calves had seroconverted to M. haemolytica.     

Arachidonate metabolites in bronchoalveolar lavage fluid from horses with and without COPD.

Arachidonate metabolites were measured in bronchoalveolar lavage fluid (BALF) from horses with (N = 4) and without (N = 7) chronic obstructive pulmonary disease (COPD). Prostaglandin (PG) D2, leukotriene (LT) B4 and LTC4 were present in highest concentrations in BALF from clinically normal horses. Concentrations of PGE2 and PGF were significantly higher in BALF from horses with COPD than in BALF from normal horses, but no differences were detected in thromboxane B2, 6-keto-PGF1 alpha, PGD2, LTB4 or LTC4.     

Cytological analysis of bronchoalveolar lavage fluid acquired by bronchoscopy in healthy ferrets: A pilot study

The objective of this study was to investigate the normal cytological evaluation of bronchoalveolar lavage (BAL) fluid in healthy adult ferrets (N = 12). These ferrets underwent bronchoscopy and BAL using sterile saline [1.5 mL/kg body weight (BW)]. Percentage of fluid recovered, total leukocyte count, differential leukocyte count, and cell count of the epithelial lining fluid (ELF) were determined. The mean percentage of lavage volume recovered from the right lung and left lung were 67.8 ± 14.9% and 69.7 ± 20.0%, respectively. Gender (P = 0.12) and weight (P = 0.17) did not significantly affect the mean percentage of recovered volume. The mean percentage of recovered volume (P = 0.47) and the mean leukocyte count (P = 0.17) from the right and left lung were not significantly different. Macrophages were the main leukocyte component of the lavages, followed by neutrophils, lymphocytes, and eosinophils. The mean proportion of ELF in BAL fluid was 9.3 ± 3.7% v/v. Bronchoscopy is clinically useful for collecting good quality BAL samples for cytological analysis in ferrets. The leucocyte differential was established, which may help veterinarians to make better clinical decisions when treating respiratory disease. Further studies are required with a larger group in order to establish the healthy reference intervals for BAL values in ferrets.