SciCombinator

Discover the most talked about and latest scientific content & concepts.

Journal: The Journal of veterinary medical science / the Japanese Society of Veterinary Science

153

Infectious bursal disease (IBD) is characterized by immunosuppression due to the depletion of lymphocytes in the atrophied bursa of Fabricius (BF). We have sometimes encountered contradictory findings: chickens infected with the vaccine IBD virus (IBDV) strain have sometimes exhibited a highly atrophied BF but not immunosuppression. In this study, chickens administered vaccine or wild-type strains of IBDV were later vaccinated with the B1 strain of the Newcastle disease virus (NDV). Bursal changes were examined histologically with a focus on the bursal follicle. The immunoreactivity to NDV was also evaluated with the hemagglutination inhibition test. In gross examination, we observed a few chickens with a severely atrophied BF in vaccine strain-administered groups (vaccine groups), and the level of severity was the same as that in the wild-type strain-administered group (wild-type group). However, these chickens retained humoral antibody responses to NDV and were revealed to possess a higher number of bursal follicles than those of the wild-type group. These results indicated that macroscopic evaluation dose not accurately reflect the immunoreactivity and degree of bursal damage in IBDV-administered chickens. We also found non-immunosuppressed chickens in the wild-type group. These non-immunosuppressed chickens retained a significantly higher number of normal follicles and total follicles according to our statistical analysis. Furthermore, a high correlation coefficient between the NDV-HI titer and the number of normal follicles was found in the wild-type group. These results implied that the retained number of normal follicles is important for the immunoreactivity of chickens infected with IBDV.

Concepts: Immune system, Antibody, Vaccine, Infection, B cell, Humoral immunity, Newcastle disease, Hieronymus Fabricius

152

In this study, scaling, polishing and daily tooth brushing were performed in 20 beagle dogs, and the number of oral bacteria was determined using a bacterial counter. The dogs were randomized into the scaling (S), scaling + polishing (SP), scaling + tooth daily brushing (SB) and scaling + polishing + tooth daily brushing (SPB) groups. Samples were collected from the buccal surface of the maxillary fourth premolars of the dogs immediately after scaling and every week thereafter from weeks 1 to 8. Throughout the study, the number of bacteria was significantly lower in the SB and SPB groups compared with the S group. The findings suggest that daily tooth brushing inhibited oral bacterial growth in the dogs.

Concepts: Bacteria, Evolution, Microbiology, Beagle, Bacterial cell structure, Bacteriology

151

The purpose of this prospective study was to establish the ultrasonographic characteristics of the dimension of the right pancreatic lobe with that of the associated anatomic landmarks in healthy dogs. Ultrasonographic examinations were performed on 25 dogs. The thickness of the right pancreatic lobe was compared with that of mural thickness of duodenum, diameters of duodenum, pancreatic duct, abdominal aorta, portal vein, caudal vena cava, and length and width of the right kidney and right adrenal gland. The correlation between each pancreatic parameter and the dimensions of the anatomical landmarks were assessed using linear regression analysis and Pearson’s correlation coefficient ® test. Significant, but weak linear correlations were observed between thickness of right pancreatic lobe with that of duodenum mural thickness (r=0.605, R(2)=0.339, P=0.001); duodenum diameter (r=0.573, R(2)=0.299, P=0.003); and right adrenal gland length (r=0.508, R(2)=0.052, P=0.01). There was no significant dimensional relationship with other selected anatomic landmarks. The ratio between the thickness of right pancreatic lobe and the mural thickness of duodenum, diameter of duodenum and length of right adrenal gland were 2.88 ± 0.53, 1.27 ± 0.27, and 0.81 ± 0.15, respectively. Calculating the ratio of thickness of the right pancreatic lobe with the dimension of significantly correlated anatomic landmarks is a useful and simple method for evaluating the size of the right pancreatic lobe in dogs in clinical practice.

Concepts: Kidney, Pancreas, Spearman's rank correlation coefficient, Abdominal aorta, Correlation and dependence, Pearson product-moment correlation coefficient, Covariance and correlation, Adrenal gland

151

Ticks carry and transmit a remarkable array of pathogens including bacteria, protozoa and viruses, which may be of veterinary and/or of medical significance. With little to no information regarding the presence of tick-borne zoonotic pathogens or their known vectors in southern Africa, the aim of our study was to screen for Anaplasma phagocytophilum, Borrelia burgdorferi, Coxiella burnetii, Rickettsia species and Ehrlichia ruminantium in ticks collected and identified from ruminants in the Eastern Cape, Free State, KwaZulu-Natal and Mpumalanga Provinces of South Africa. The most abundant tick species identified in this study were Rhipicephalus evertsi evertsi (40%), Rhipicephalus species (35%), Amblyomma hebraeum (10%) and Rhipicephalus decoloratus (14%). A total of 1,634 ticks were collected. DNA was extracted, and samples were subjected to PCR amplification and sequencing. The overall infection rates of ticks with the target pathogens in the four Provinces were as follows: A. phagocytophilum, 7%; C. burnetii, 7%; E. ruminantium, 28%; and Rickettsia spp., 27%. The presence of B. burgdorferi could not be confirmed. The findings of this study show that zoonotic pathogens are present in ticks in the studied South African provinces. This information will aid in the epidemiology of tick-borne zoonotic diseases in the country as well as in raising awareness about such diseases in the veterinary, medical and tourism sectors, as they may be the most affected.

Concepts: Bacteria, Africa, Coxiella burnetii, Q fever, Lyme disease, South Africa, Borrelia burgdorferi, Eastern Cape

148

The presence of circulating tumor cells (CTCs) serves as a prognostic marker and indicator of disease relapse, as well as a means of evaluating treatment efficacy in human and canine lymphoma patients. As an extension of our previous study for the construction of clinically useful GeneScan system, we utilized the GeneScan system for detecting CTCs in canine lymphoma patients. Samples from the primary lesion and peripheral blood mononuclear cells (PBMCs) were obtained from 32 dogs with lymphoma at initial diagnosis. All samples were subjected to polymerase chain reaction (PCR) for antigen receptor gene rearrangements (PARR) followed by GeneScan analysis. Common clonal rearrangements with identical amplified fragments were detected in both the primary lesion and PBMCs in 19 of the 32 dogs (59.4%). However, the detection rate of CTCs varied among the anatomical classification of lymphoma studied. GeneScan analysis following PARR would facilitate studies on determining the clinical significance of CTCs in canine lymphoma patients.

Concepts: DNA, Protein, Gene expression, Cancer, Polymerase chain reaction, Molecular biology, PBMC, Thermus aquaticus

147

Although papillomaviruses (PVs) have been widely reported in vertebrates, there have been only a few PV reports in yaks (Bos grunniens). In 2012, Bam et al. reported bovine papillomavirus type 1 (BPV-1) and BPV-2 associated with cutaneous papillomatosis in yaks, which provided genomic and pathology information for yak PVs. However, nucleotide identity and phylogenic analyses revealed that there are two isolates with a high possibility of belonging to a novel type that is not BPV-1. The argument was thought to be caused by type-specific primers. Our analysis showed that BPV-1 type-specific primers can detect not only BPV-1 but also other PVs. It suggests that identification results using type-specific primers should be confirmed with more robust methods in molecular epidemiological studies.

Concepts: Papillomavirus, Cattle, Bovine papillomavirus, Papillomaviridae, Bovines, Bos, Yak, Gaur

146

A 2-month old foal with septic shock and severe respiratory distress was referred to the Veterinary Teaching Hospital. Due to poor prognosis, the foal was euthanized. Histopathology showed lesions suggestive of Rhodococcus equi infection associated with a diffuse interstitial infiltrate of foamy macrophages and syncytial cells presenting large acidophilic intranuclear inclusion bodies, fibrin exudates and hyaline membranes. Bacteriological examination from lung and respiratory exudates confirmed R. equi infection, whilst immunohistochemistry and PCR yielded a positive result for Equid herpesvirus type 1(EHV-1). Several etiologies have been proposed for bronchointerstitial pneumonia in foals, although a multifactorial origin for this lesional pattern could be possible. This work is the first one describing a combined EHV-1 and R. equi infection in a foal affected with bronchointerstitial pneumonia.

Concepts: Bacteria, Pulmonology, Microbiology, Anatomical pathology, Histology, Acute respiratory distress syndrome, Cytomegalovirus, Inclusion bodies

146

We improved a loop-mediated isothermal amplification (LAMP) assay permitting sensitive and rapid Mycoplasma bovis detection. A total of 55 bacterial strains were examined in this study, including 33 M. bovis strains, 14 non-M. bovis mycoplasmas and eight non-mycoplasma bacterial strains. M. bovis was successfully detected by the LAMP assay within 60 min without cross-reaction to any other bacteria. Furthermore, a total of 135 nasal swab samples were tested directly using our LAMP assays, the previously reported LAMP assay, conventional PCR assay without pre-culture and comparing standard culture methods. The improved LAMP assay showed sensitivity and specificity of 97.2% and 90.9%, respectively (with a kappa coefficient of 0.8231), and the sensitivity of our revised LAMP assay was increased compared to existing methods.

Concepts: Bacteria, Sensitivity and specificity

144

Orf virus infection has been prevalent continuously in the population of wild Japanese serows (Capricornis crispus), goat-like grazing cloven-hoofed mammal species that live mainly in mountainous areas of Japan. Currently, definitive diagnosis of infection requires time-consuming laboratory work. To diagnose rapidly on-site, we developed a field-friendly procedure for the detection of orf virus from oral cavity lesions. DNA was extracted from goat saliva spiked with orf virus as a proxy for Japanese serows by a commercial kit without the use of electricity, and the quality of the extracted DNA was evaluated by conventional polymerase chain reaction (PCR). Extracted DNA was amenable to DNA amplification, the same as when extracted in a laboratory. Next, to find optimal conditions for DNA amplification by loop-mediated isothermal amplification (LAMP), Bst and Csa DNA polymerases and 3 colorimetric indicators for visual diagnosis, hydroxy naphthol blue (HNB), malachite green and D-QUICK, were compared using a portable cordless incubator. The combination of Bst or Csa DNA polymerase with HNB was found to be easiest for visual diagnosis by the naked eye, and viral DNA was successfully amplified from all orf virus strains used. These results suggest that the procedure established here can work completely on-site and can be useful for definitive diagnosis and differentiation of orf virus infection in Japanese serows in remote mountainous areas.

Concepts: DNA, Polymerase chain reaction, Enzyme, DNA replication, Reverse transcriptase, DNA polymerase, Polymerase, Primer

26

We investigated the responsiveness of the mouse basilar artery to acetylcholine (ACh), bradykinin (BK), noradrenaline (NA), 5-hydroxytryptamine (5-HT), histamine (His) and angiotensin (Ang) II in order to characterize the related receptor subtypes in vitro. ACh and BK induced endothelium-dependent relaxation of precontracted arteries with U-46619 (a thromboxane A2 analogue). Atropine (a non-selective muscarinic receptor antagonist) and Nω-nitro-L-arginine (a NO synthase inhibitor, L-NNA) shifted the concentration-response curve for ACh to the right, whereas pirenzepine, methoctramine and pFHHSiD (muscarinic M1, M2 and M3 antagonists, respectively) had no significant effect. L-NNA and HOE140 (a B2 antagonist) shifted the concentration-response curve for BK to the right, whereas Des-Arg(9)-[Leu(8)]-BK (a B1 antagonist) and indomethacin (a COX inhibitor) had no significant effect. NA failed to produce any vasomotor action. His and Ang II induced concentration-dependent contraction. Diphenhydramine (a H1 antagonist) shifted the concentration-response curve for His to the right, whereas cimetidine (a H2 antagonist) had no significant effect. Losartan (an AT1 antagonist) shifted the concentration-response curve for Ang II to the right, whereas PD123319 (an AT2 antagonist) had no significant effect. These results suggest that the H1 and AT1 receptor subtypes might play an important role in arterial contraction, whereas muscarinic receptor subtypes other than M1, M2 and M3, and B2 receptors on the endothelium, might modify these contractions to relaxations.

Concepts: Blood pressure, Receptor, Receptor antagonist, Neurotransmitter, Acetylcholine, G protein coupled receptors, Muscarinic acetylcholine receptor, Atropine