Prevalence of Chlamydophila felis and feline herpesvirus 1 in cats with conjunctivitis in northern Italy

The prevalence of Chlamydophila felis and feline herpesvirus 1 (FHV-1) infection in cats with conjunctivitis in northern Italy was investigated by conventional polymerase chain reaction (PCR) testing. In cats with conjunctivitis, C felis and FHV-1 were detected in 14 of 70 (20%) and in 23 of 70 (33%) animals, respectively. None of the 35 control cats were positive for C felis, whereas 7 (20%) of these cats were positive for FHV-1. Mixed infections were present in 5 of 70 cats (7%). Cats positive for C felis were significantly younger than control animals (P = .02), whereas no significant age differences were observed between FHV-1-positive cats and control cats (P = .41) or between FHV-1-positive animals and C felis-positive animals (P = .16). Cats sampled during acute-phase conjunctivitis were also investigated for the presence of C felis by conjunctival scrapings. In this acute phase, substantial agreement was found when comparing the results of the 2 methods (K = .80). The association between PCR results and conjunctivitis was evaluated for the 2 pathogens. The presence of C felis was significantly associated with conjunctivitis (P = .004), whereas the detection of FHV-1 did not significantly correlate with the clinical sign (P = .25), suggesting that, by itself. PCR is not suitable for the diagnosis of FHV-1-related conjunctivitis.     

Tritrichomonas foetus and Mycoplasma felis coinfection in the upper respiratory tract of a cat with chronic purulent nasal discharge

A 5‐year‐old indoor male neutered Siamese cat was presented with clinical signs of sneezing and chronic bilateral purulent nasal discharge. Multiple nasal cavity swabs were submitted for bacterial cultures, Mycoplasma felis‐DNA qPCR, and cytology. M felisqPCR was positive and cytomorphologic diagnosis was severe, acute, purulent, rhinitis with intralesional protozoal microorganisms consistent with a Trichomonas spp. Nested PCR (nPCR) confirmed the diagnosis of Tritrichomonas foetus. Systemic therapy with doxycycline for M felis and metronidazole for T foetus was started with remission of clinical signs within 2 weeks; however, symptoms relapsed shortly after therapy was discontinued. This study represents the first documented case of T foetus associated with chronic nasal discharge in a cat, which supports the hypothesis that T foetus can live in the nasal cavity. It is also the first reported case of M felis and T foetus coinfection, which indicates that with mycoplasmal feline upper respiratory tract infections, T foetus should be considered as a coinfecting agent.     

An investigation into the role of Chlamydophila spp. in bovine upper respiratory tract disease

An outbreak of upper respiratory tract disease was investigated in a group of 17 housed home-bred calves on a mixed dairy, beef and sheep farm in Devon. Conjunctival swabs were collected and tested for Chlamydophila spp. DNA using a PCR test that detects Chlamydophila abortus and Chlamydophila psittaci. Six of the calves tested gave a positive result. Further epidemiological observations and laboratory testing indicated that the adult dairy cows, from which the affected calves originated, were the most likely source of infection.     

Risk factors for time to diagnosis of feline upper respiratory tract disease in UK animal adoption shelters

Feline upper respiratory tract disease (URTD), mainly caused by feline calicivirus (FCV) and feline herpesvirus, is a major cause of disease outbreaks in feline accommodation such as animal shelters, catteries and multi-cat households. We conducted a longitudinal, yearlong study in five UK feline animal shelters to identify risk factors for the time to diagnosis of URTD. We were especially interested in risk factors that could be identified at the time the cat entered the shelter. Shelter staff recorded data for 1434 cats during 2002–2003. Most of the cats were domestic shorthair cats and were from private households, or were stray or abandoned. Sixty cats without clinical signs of URTD at entry had URTD diagnosed (typically within the first month at the centre). We used two multivariable models: one was a Cox proportional-hazards model, and the other a regression analyses with complementary log–log model.The hazard varied substantially between shelters and was considerably lower for the shelter that had a purpose-built admissions unit with its own isolation facilities. The hazard was greater for purebred cats (HR 4.3–5.0) and for neutered cats (HR 2.0). The hazard was also typically greater if the centre had a greater proportion of cats present with URTD. The analyses suggested that the centre-level risk factors were more important in determining hazard than cat-level risk factors.     

Factors associated with upper respiratory tract disease caused by feline herpesvirus, feline calicivirus, Chlamydophila felis and Bordetella bronchiseptica in cats: experience from 218 European catteries

A full history of the management practices and the prevalence of upper respiratory tract disease (URTD) at 218 rescue shelters, breeding establishments and private households with five or more cats was recorded. Oropharyngeal and conjunctival swabs and blood samples were taken from 1748 cats. The prevalences of feline herpesvirus (FHV), feline calicivirus (FCV), Chlamydophila felis and Bordetella bronchiseptica were determined by PCR on swab samples. An ELISA was applied to determine the prevalence of antibodies to B. bronchiseptica. The rates of detection by PCR of each pathogen in the cats in catteries with and without ongoing URTD were, respectively, FHV 16 per cent and 8 per cent; FCV 47 per cent and 29 per cent; C. felis 10 per cent and 3 per cent; and B. bronchiseptica 5 per cent and 1.3 per cent; the seroprevalences of B. bronchiseptica were 61 per cent and 41 per cent, respectively. There was evidence that FHV, FCV and B. bronchiseptica played a role in URTD. The risk factors associated with the disease were less than excellent hygiene, contact with dogs with URTD, and larger numbers of cats in the cattery or household.     

Anatomy of the upper respiratory tract in domestic birds,with emphasis on vocalization

This work reviews the anatomy of the upper respiratory tract in domestic birds including the chicken and pigeon. Non‐exhaustive additional information on other bird species, illustrating the extraordinary diversity in the biological class Aves, can be found in several footnotes. The described anatomical structures are functionally considered in view of avian sound production. In particular, the Syrinx is invaluable. Its most important structures are the Labia and the lateral and medial tympaniform membranes in non‐songbirds and songbirds, respectively. These structures produce sound by vibrating during expiration and eventually inspiration.     

Assessment of dynamic upper respiratory tract function in the equine athlete

Dynamic upper respiratory tract (URT) obstructions occur commonly in the equine athlete. During the past 25 years, veterinary diagnostic capabilities have improved greatly with the ability to perform endoscopy during exercise and thus to visualise upper airway function during various types of exercise. After correctly reproducing and diagnosing an URT obstruction, the veterinary surgeon must consider the functional significance of the endoscopic findings for that individual athlete. This is the third paper in this series and focuses on the diagnosis of URT obstructions, their relationship to the exercise test and their functional significance.     

Relative prevalence of upper respiratory tract obstructive disorders in two breeds of harness racehorses (185 cases: 1998-2006)

Reasons for performing study: Two genetically and phenotypically distinct horse breeds are used for harness racing in Scandinavia: the Standardbred (SB) and Coldblooded Trotter. These racehorses have identical environmental, management and racing conditions. Therefore, this study was undertaken to identify and compare the relative prevalence of upper respiratory tract (URT) obstructive disorders in these 2 breeds. Objectives: To determine whether these 2 phenotypically different breeds of harness racehorses have different predispositions for URT disorders. Methods: Retrospective study of 88 Norwegian Coldblooded Trotters (NCT) and 97 SBs referred to this hospital for URT evaluation between 1998 and 2006. Case records of all horses diagnosed with an URT disorder during resting endoscopy, and all horses undergoing high‐speed treadmill videoendoscopy (HSTV) with one or more periods of induced poll flexion were evaluated. The relative prevalence of URT disorders between the 2 breeds was analysed using a Fisher's exact test. Results: There was a significant (P<0.05) breed predisposition regarding 6 URT disorders. Bilateral dynamic laryngeal collapse associated with poll flexion and flaccid epiglottis was significantly more frequent in the NCT. Alar fold collapse and nasopharyngeal collapse were significantly more frequent in SBs. Epiglottic entrapment and nasal flutter were only diagnosed in the SBs. Dynamic disorders were more common than resting disorders in both breeds. Conclusion: URT obstructive disorders (dynamic laryngeal collapse associated with poll flexion, flaccid epiglottis, pharyngeal collapse, alar fold collapse, nasal flutter and epiglottic entrapment) are breed related, indicating an anatomic or functional cause. Periods of induced poll flexion during HSTV was essential to declare harness racehorses free of URT disorders. Potential relevance: Further anatomic or physiological studies comparing these breeds could potentially provide insight into the pathogenesis of certain URT obstructive disorders. Induced poll flexion should be included in routine HSTV examinations of all harness racehorses.     

Effect of cilobradine in cats with a first episode of congestive heart failure due to primary cardiomyopathy

IntroductionHeart rate (HR) is often elevated in cats with cardiomyopathies (CMPs). Pharmacologic modulation of HR may reduce cardiac morbidity and mortality.ObjectivesTo investigate the effects of cilobradine vs. placebo, regarding time to cardiac mortality or morbidity in cats with first episode of congestive heart failure (CHF) due to primary CMP.AnimalsThree hundred and sixty-seven client-owned cats with primary CMP that had presented with a first episode of CHF at 50 centers in Europe. Per-protocol population comprised 193 cats (n = 89 cilobradine, n = 104 placebo). An interim analysis for futility was planned.MethodsProspective, randomized, placebo-controlled, double-blinded, multicenter clinical trial. Primary outcome variable was the time to a composite of cardiac mortality or cardiac morbidity.ResultsMedian time to primary outcome was 84 days (95% confidence interval [CI]: 63–219 days) in the cilobradine group (CG) and 203 days in the placebo group (95% CI: 145–377 days) with observed hazard ratio of 1.44, indicating a higher hazard for the CG (P = 0.057). Mean HR was 28 beats per minute (bpm) lower at Day 7 (P < 0.0001) and remained 29 bpm lower at Day 360 (P = 0.026) in the CG than that in the placebo group. Although the number of adverse events did not differ, there were more serious adverse events in the CG.ConclusionsHeart rate reduction by cilobradine in cats with a first episode of CHF due to primary CMP did not reduce cardiac mortality and morbidity.     

Correlation of rhinoscopic signs of inflammation with histologic findings in nasal biopsy specimens of cats with or without upper respiratory tract disease

OBJECTIVE: To investigate the correlation of cumulative rhinoscopic findings of hyperemia, mucus accumulation, and turbinate destruction with the type and severity of inflammatory infiltrates in nasal biopsy specimens of cats with or without upper respiratory tract disease. DESIGN: Prospective study. ANIMALS: Cats with (n = 11) and without (6) upper respiratory tract disease and cats with unknown medical histories (27). PROCEDURES; Lesions of hyperemia, mucus accumulation, and turbinate destruction detected rhinoscopically were each scored (scale, 0 [absent] to 3 [severe]), and a cumulative rhinoscopic score for each nasal cavity was calculated. Fifty biopsy specimens were examined histologically, and inflammatory infiltrates (lymphoplasmacytic or neutrophilic) were graded as absent, mild, moderate, or severe. Cumulative rhinoscopic scores and inflammation grades were compared for each specimen-cavity combination. RESULTS: In cats of known disease status, there was a positive but weak correlation between cumulative rhinoscopic scores and inflammation grades in biopsy specimens. In cats of unknown disease status, there was no similar correlation. Biopsy specimens with minimal inflammation were commonly obtained from nasal cavities with low rhinoscopic scores; specimens with moderate or severe inflammatory changes were frequently obtained from cavities that appeared normal rhinoscopically. Type of inflammatory infiltrates was not correlated with rhinoscopic signs of inflammation. CONCLUSIONS AND CLINICAL RELEVANCE: The correlation of rhinoscopic findings with inflammation severity in nasal biopsy specimens (determined histologically) was weak or lacking in cats of known and unknown disease status, respectively. Results indicated that rhinoscopy with biopsy provides more complete evaluation of nasal disease than rhinoscopy alone in cats.     

Evaluation of serologic and viral detection methods for diagnosing feline herpesvirus-1 infection in cats with acute respiratory tract or chronic ocular disease

OBJECTIVE: To determine the value of virus isolation (VI), immunofluorescent antibody (IFA) assay, serum neutralization (SN), and ELISA for the diagnosis of clinical feline herpesvirus-1 (FHV-1) infection in cats. ANIMALS: 46 clinically normal cats, 17 cats with signs of acute respiratory tract disease, and 38 cats with signs of chronic ocular disease. PROCEDURE: Conjunctival swabs for VI, conjunctival scrapings for IFA testing, and venous blood samples for SN or ELISA testing were obtained from all cats. RESULTS: FHV-1 was detected in 10.9 and 28.3% of clinically normal cats and in 18.2 and 33.3% of cats with FHV-1-associated disease by VI and the IFA assay, respectively. There were no significant differences in the viral detection rate between cats with acute respiratory tract disease and cats with chronic ocular disease or between diseased cats and clinically normal cats; however, FHV-1 was never detected by both methods in clinically normal cats. Overall FHV-1 seroprevalence was 97% when tested by ELISA and 66% when tested by SN. Seroprevalence did not vary significantly among the 3 groups for either serologic test. Magnitude of SN and ELISA titers varied greatly but independently of presence or absence of clinical signs of FHV-1-associated disease. Sensitivity, specificity, and positive and negative predictive values were assessed for VI and the IFA assay--jointly and individually--and for each SN and ELISA titer magnitude. Values never all exceeded 50%. CLINICAL IMPLICATIONS: Because FHV-1 can be detected commonly in clinically normal cats by the IFA assay or VI, neither test appears to aid in the clinical diagnosis of FHV-1 infection. Seroprevalence does not appear to vary between affected and clinically normal cats. SN, ELISA, VI, and the IFA assay appear to be of limited value in the diagnosis of FHV-1-associated disease in cats. Concurrent assessment of the IFA assay and VI results may permit exclusion of FHV-1 as an etiologic agent if results of both tests are negative.     

Antibiotic prophylaxis of lower respiratory tract contamination in horses confined with head elevation for 24 or 48 hours

Objective To evaluate the administration of procaine penicillin prior to or during confinement with head elevation as a means of reducing the associated accumulation of inflammatory lower respiratory tract secretions and increased numbers of bacteria within the lower respiratory tract of confined horses. Design and Procedure Two experiments were conducted to evaluate the efficacy of different dose rates and dosing frequencies. In experiment A a single low dose (15,000 IU/kg) of procaine penicillin was administered to four horses immediately prior to confinement with head elevation for 48 hours. The systemic leucocyte response, gross and cytologic characteristics of transtracheal aspirate and bacterial numbers in lower respiratory tract samples were compared with corresponding samples from two horses confined with heads elevated but not given penicillin. The efficacy of higher dose rates (20,000 IU/kg and 40,000 IU/kg) given before and during confinement with heads elevated for 24 hours was evaluated in experiment B. Results Treatment with procaine penicillin had no effect on the systemic leucocyte response or on the accumulation of inflammatory lower respiratory tract secretions at any of the dosing schedules evaluated. The number of bacteria isolated from trans-tracheal samples was reduced at 12 hours for treated horses in experiment A and at 24 hours for experiment B. β-haemolytic Streptococcus spp were not isolated from treated horses in either experiment. Bacterial species isolated from treated horses were predominantly Pasteurella and/or Actinobacillus spp, however, members of the family Enterobacteriaceaé and a Staphylococcus sp were isolated from treated horses. One treated horse in experiment A developed clinically apparent pulmonary disease. Conclusions The prophylactic administration of penicillin before or during confinement did not reliably reduce bacterial numbers or prevent the accumulation of purulent lower respiratory tract secretions in horses confined with their heads elevated. Numbers of β-haemolytic Streptococcus spp were reduced following treatment, suggesting that the repeated administration of procaine penicillin may have some merit as part of a strategy to prevent transport-associated respiratory disease. However, methods directed at minimising the duration of confinement with head elevation, augmentation of the clearance of accumulated secretions and prompt identification of animals in which airway inflammation has extended to the pulmonary parenchyma remain the best ways of minimising transport-associated respiratory disease.     

The kinetics of feline leukaemia virus shedding in experimentally infected cats are associated with infection outcome

Feline leukaemia virus (FeLV) infection in felids results mainly from oronasal exposure to infectious saliva and nasal secretions, but the potential for viral transmission through faeces and urine has not been completely characterized. In order to assess and compare potential FeLV transmission routes, we determined the viral kinetics in plasma, saliva, faeces and urine during early experimental FeLV infection (up to week 15 post-exposure) in specific pathogen-free cats. In addition to monitoring p27 antigen levels measured by ELISA, we evaluated the presence of infectious particles by cell culture assays and quantified viral RNA loads by a quantitative real-time TaqMan polymerase chain reaction. RNA load was associated with infection outcome (high load-progressive infection; low load-regressive infection) not only in plasma, but also in saliva, faeces and urine. Infectious virus was isolated from the saliva, faeces and urine of infected cats with progressive infection as early as 3-6 weeks post-infection, but usually not in cats with regressive infection. In cats with progressive infection, therefore, not only saliva but also faeces and to some extent urine might represent potential FeLV transmission routes. These results should be taken into account when modelling FeLV-host interactions and assessing FeLV transmission risk. Moreover, during early FeLV infection, detection of viral RNA in saliva may be used as an indicator of recent virus exposure, even in cats without detectable antigenaemia/viraemia. To determine the clinically relevant outcome of FeLV infection in exposed cats, however, p27 antigen levels in the peripheral blood should be measured.     

Economic loss due to treatment of bovine respiratory disease in Japanese Black calves arriving at a backgrounding operation in Miyazaki

The present study assessed the economic loss due to treatment of bovine respiratory disease (BRD) in Japanese Black calves that were introduced to a backgrounding operation from the age of 3 to 4 months until the age of 10 months. The data collected from a backgrounding operation in Miyazaki, Japan included the records of 2,690 animals entering the farm from 2013 to 2018. The treatment duration was defined as the number of days from the beginning to end of treatment. The cost of treatment was defined as the total cost of treatment during the treatment duration. The average incidence of BRD was 54.6%, and the relative frequency of calves that had BRD once, twice, and three or more times until they left the farm was 64.4%, 26.8%, and 8.8%, respectively (total recorded diagnoses of BRD: 2,494). Among the 2,494 recorded diagnoses, the average and median duration of treatment of BRD was 5.9 days and 3.0 days, respectively. The average and median cost of treatment was 7,767 and 5,600 Japanese yen, respectively. A prolonged duration of treatment and high cost of treatment were associated with BRD relapse, steers, and early stage of production (P<0.05). At the studied farm, the total cost of treatment during the 6-year study period was 19,658,988 yen, and the annual cost was approximately 3 million yen. In summary, the present study showed that BRD had a large economic impact in this backgrounding operation.     

Serum concentrations of cardiac troponin I and cardiac troponin T in dogs with class IV congestive heart failure due to mitral valve disease

Objective: The objective of this study was to evaluate the incidence of circulating detectable serum levels of cardiac troponin I (CTnI) and circulating detectable serum levels of cardiac troponin T (CTnT) in dogs with class IV congestive heart failure (CHF) due to mitral valve disease (MVD) at admission. An additional study aim was to determine if detectable troponin levels correlated with the magnitude of several clinical parameters. Design: Prospective clinical investigation. Setting: Small animal emergency and critical care referral hospital. Interventions: Blood was collected before emergency treatment from 15 dogs presenting in class IV CHF due to MVD. Measurements: Serum concentrations of CTnI, CTnT at presentation. Main results: Six dogs (40%) had a detectable CTnI (median 0.24, range 0.12–0.31 ng/mL), and the remainder were less than 0.1 ng/mL and deemed non‐detectable. The one dog (7%) that had a detectable CTnT (0.02 ng/mL) also had a detectable CTnI (0.23 ng/mL). There was no statistical difference in survival to discharge between dogs with non‐detectable troponin levels and those with detectable troponin levels; however, dogs with detectable troponin levels had shorter overall survival times. Dogs with a detectable level of CTnI had a median survival of 67.5 days (range 1–390 days), and dogs with a non‐detectable level of CTnI had a median survival time of 390 days (range 20–912 days) (P=0.02). Conclusion: This study suggests that CTnI can be detected at admission in the blood of 40% of dogs with class IV CHF due to MVD. Dogs with non‐detectable levels of cardiac troponins had a significantly longer overall survival time. The encouraging results of this small pilot study warrant further investigation.