Veterinary Clinical Sciences - Research Publications
Now showing items 1-12 of 23
Influence of allergen-specific immunotherapy on allergen-specific IgG subclasses in dogs with atopic dermatitis
Canine atopic dermatitis (AD) is one of the most common pruritic skin diseases in dogs and is diagnosed based on compatible history, clinical signs and exclusion of other pruritic skin diseases. Allergen-specific immunotherapy (ASIT) is widely used to treat AD but the precise mechanism of action is unknown. The aims of our study were to investigate the influence of ASIT on levels of Dermatophagoides farinae (D. farinae) specific IgG (D. farinae-IgG) subclasses and to explore whether changes in IgG subclasses are associated with the efficacy of ASIT. Sera from 98 dogs were collected before and during ASIT (duration of at least 2 years) with D. farinae. All dogs had serum IgE specific for D. farinae (imovet bg assay). Atopic dogs were divided into two groups: ASIT Group (n=48, ASIT as the sole therapy) and ASIT+ Group (n=50, insufficient control with ASIT requiring additional glucocorticoid treatment). A control group (CTRL Group, n=32) consisted of dogs without dermatological disease. Allergen-specific IgG subclass antibodies were detected by ELISA using monoclonal antibodies specific for canine IgG1 – IgG4. D. farinae-IgG1 and IgG4 were detected in >78% of all sera before ASIT while D. farinae-IgG2 and IgG3 were found in < 31%. Prior to therapy, dogs from the ASIT Group had significantly higher serum D. farinae-IgG1 than dogs in the ASIT+ Group (p<0.05). ASIT led to a significant increase in D. farinae-IgG1 in dogs from the ASIT (p<0.05) and ASIT+ (p<0.01) groups. D. farinae-IgG2, IgG3 and IgG4 concentrations were comparable for all groups before and during ASIT. Allergen-specific IgE concentration was not influenced by ASIT and the concentrations of IgG1 and IgG4 specific to an irrelevant antigen (Betula; birch pollen) were not influenced by ASIT against D. farinae. We conclude that long term ASIT increases levels of D. farinae-IgG1 and that dogs responding well to ASIT have a higher D. farinae-IgG1 concentration before therapy than partial responders.
EIMERIA TAGGARTI N. SP., A NOVEL COCCIDIAN (APICOMPLEXA: EIMERIORINA) IN THE PROSTATE OF AN ANTECHINUS FLAVIPES
(AMER SOC PARASITOLOGISTS, 2018-02-01)
A novel coccidian species was discovered in the prostate of an Antechinus flavipes (yellow-footed antechinus) in South Australia during the period of postmating male antechinus immunosuppression and mortality. This novel coccidian is unusual because it develops extraintestinally and sporulates endogenously within the prostate gland of its mammalian host. Histological examination of prostatic tissue revealed dense aggregations of spherical and thin-walled tetrasporocystic, dizoic, sporulated coccidian oocysts within tubular lumina, with unsporulated oocysts and gamogonic stages within the cytoplasm of glandular epithelial cells. This coccidian was observed occurring concurrently with dasyurid gammaherpesvirus 1 infection of the antechinus' prostate. Eimeria-specific 18S small-subunit ribosomal (r)DNA polymerase chain reaction amplification was used to obtain a partial 18S rDNA nucleotide sequence from the antechinus coccidian. Bayesian phylogenetic analysis based on 18S rDNA gene sequences revealed that the novel coccidian clusters with reptile-host coccidians, forming an ancestral basal lineage of the eimeriid clade. The species has been named Eimeria taggarti n. sp. on the basis of both sporulated oocyst morphology and molecular characterization. It is suspected that E. taggarti is sexually transmitted via excretion of sporulated oocysts or free sporocysts with prostatic secretions in semen.
A high prevalence of beak and feather disease virus in non-psittacine Australian birds
(MICROBIOLOGY SOC, 2017-07-01)
PURPOSE: Beak and feather disease virus (BFDV) is a circovirus and the cause of psittacine beak and feather disease (PBFD). This disease is characterized by feather and beak deformities and is a recognized threat to endangered Psittaciformes (parrots and cockatoos). The role that non-psittacine birds may play as reservoirs of infection is unclear. This study aimed to begin addressing this gap in our knowledge of PBFD. METHODOLOGY: Liver samples were collected from birds presented to the Australian Wildlife Health Centre at Zoos Victoria's Healesville Sanctuary for veterinary care between December 2014 and December 2015, and tested for BFDV DNA using polymerase chain reaction coupled with sequencing and phylogenetic analyses.Results/Key findings. Overall BFDV was detected in 38.1 % of 210 birds. BFDV was detected at high prevalence (56.2 %) in psittacine birds, in the majority of cases without any observed clinical signs of PBFD. We also found that BFDV was more common in non-psittacine species than previously recognized, with BFDV detected at 20.0 % prevalence in the non-psittacine birds tested, including species with no clear ecological association with psittacines, and without showing any detectable clinical signs of BFDV infection. CONCLUSION: Further research to determine the infectivity and transmissibility of BFDV in non-psittacine species is indicated. Until such work is undertaken the findings from this study suggest that every bird should be considered a potential carrier of BFDV, regardless of species and clinical presentation. Veterinary clinics and wildlife rehabilitation facilities caring for birds that are susceptible to PBFD should reconsider biosecurity protocols aimed at controlling BFDV.
The effect of recumbency position on the ultrasound measurement of the canine adrenal gland in non-adrenal gland illness
(DOVE MEDICAL PRESS LTD, 2017-01-01)
Abdominal ultrasound is frequently used to assess the canine adrenal gland (AG) and subjective and objective features of normal AGs have been described. The effect of the dogs' recumbency position on the accuracy of AG measurement acquisition is not known. This prospective study, performed in dogs with non-adrenal illness, compared ultrasonographic AG measurements made in dogs placed in dorsal recumbency with those made in left or right lateral recumbency. AG length, height and width measurements made in the longitudinal image plane, and height and width measurements from the transverse image plane were assessed. The level and limits of agreement between the dorsal and lateral recumbency for each of the measurements were determined using the Bland-Altman analysis. The measurement with the best agreement between the dorsal and lateral recumbency was the caudal pole thickness (CPT) from the longitudinal image plane. Agreement between lateral and dorsal recumbency was poorer for the measurements derived from the transverse image plane and poorest for measurements of AG length in the longitudinal plane. This study demonstrates that there is some difference in the measurements acquired in dorsal compared with lateral recumbency; however, the difference is small for the CPT from the longitudinal plane. This finding suggests that the CPT from the longitudinal image plane is the most reliable measurement in terms of agreement between dorsal and lateral recumbency in dogs with non-AG illness.
Comparison of McMaster and FECPAK(G2) methods for counting nematode eggs in the faeces of alpacas
(BIOMED CENTRAL LTD, 2018-05-02)
This study aimed to compare the FECPAKG2 and the McMaster techniques for counting of gastrointestinal nematode eggs in the faeces of alpacas using two floatation solutions (saturated sodium chloride and sucrose solutions). Faecal eggs counts from both techniques were compared using the Lin's concordance correlation coefficient and Bland and Altman statistics. Results showed moderate to good agreement between the two methods, with better agreement achieved when saturated sugar is used as a floatation fluid, particularly when faecal egg counts are less than 1000 eggs per gram of faeces. To the best of our knowledge this is the first study to assess agreement of measurements between McMaster and FECPAKG2 methods for estimating faecal eggs in South American camelids.