Correlation of inducible nitric oxide synthase (iNOS) inhibition with TNF-α, caspase-1, FasL and TLR-3 in pathogenesis of rabies in mouse model.

The role of inflammatory cytokines such as interleukin-1α/ß (IL-1α/ß), IL-6, IL-10, tumour necrosis factor-alpha (TNF-α), interferons, nitric oxide (NO) and inducible nitric oxide synthase (iNOS) in pathogenesis of rabies is being actively pursued. Presently, levels of certain immune molecules in pathogenesis of rabies in mice have been investigated. CVS strain of rabies infection resulted in early increase in iNOS, TNF-α, caspase-1, Fas ligand (FasL) and toll-like receptor-3 (TLR-3) mRNA levels in brain, and nitric oxide levels in serum. The severity of clinical signs and microscopic lesions largely correlated with NO levels. Aminoguanidine (AG; iNOS inhibitor) decreased NO production with delay in development of clinical signs and increase in survival time. Prolonged survival time correlated with reduced viral load evident by real-time PCR, reduced fluorescent signals of rabies antigen in brain and reduced immunohistochemistry signals in neuronal cytoplasm. These parameters suggested that nitric oxide did influence the rabies virus replication. Inhibition of iNOS by AG administration led to decreased expression of TNF-α, caspase-1, FasL and TLR-3 mRNA levels suggesting that increase in NO levels in rabies virus infection possibly contributed to development of disease through inflammation, apoptosis and immune-evasive mechanisms.

Virological, immunological and pathological findings of transplacentally transmitted bluetongue virus serotype 1 in IFNAR1-blocked mice during early and mid gestation.

Transplacental transmission (TPT) of wild-type Indian BTV-1 had never been experimentally proved. This study was first time investigated TPT of Indian BTV-1 (isolated from aborted and stillborn goat fetal spleens). The sequential pathology, virological and immune cell kinetics (CD4+, CD8+ T-lymphocytes and NK cells in spleen and PBMCs), and apoptosis in IFNAR1-blocked pregnant mice during early (infected on 1 GD) and mid (infected on 8 GD) gestation have been studied. There was higher rate of TPT during mid stage (71.43%) than early (57.14%) stage. In early stage reduced implantation sites, early embryonic deaths, abortions, and necro-haemorrhagic lesions had observed. Mid stage, congenital defects and neurological lesions in foetuses like haemorrhages, diffuse cerebral edema, necrotizing encephalitis and decreased bone size (Alizarin red staining) were noticed. BTV-1 antigen was first time demonstrable in cells of mesometrium, decidua of embryos, placenta, uterus, ovary, and brain of foetuses by immunohistochemistry and quantified by real-time qRT-PCR. BTV-inoculated mice were seroconverted by 7 and 5 dpi, and reached peak levels by 15 and 9 dpi in early and mid gestation, respectively. CD4+ and CD8+ cells were significantly decreased (increased ratio) on 7 dpi but subsequently increased on 15 dpi in early gestation. In mid gestation, increased CD8+ cells (decreased ratio) were observed. Apoptotic cells in PBMCs and tissues increased during peak viral load. This first time TPT of wild-type Indian BTV-1 deserves to be reported for implementation of control strategies. This model will be very suitable for further research into mechanisms of TPT, overwintering, and vaccination strategies.

Scorecard method for assessing the severity of peste des petits ruminants in sheep and goats.

A methodology to assess the clinical severity of peste des petits ruminants (PPR) in sheep and goats in the field condition was developed using a scorecard by considering five specific cardinal clinical signs (pyrexia, oculo-nasal discharge, oral lesions, respiratory signs, and diarrhoea) of disease. The scores were assigned for the signs based on the severity of the disease that ranged from 1 (low) to 4 (high). The assigned weightage for signs, morbidity, and mortality was 0.75, 0.05 and 0.2, respectively summing up to unity. The scoring and weightages and guidelines were devised by Delphi technique based on the field investigation, field veterinarian's assessment and specific inputs from PPR experts. The estimated Weighted Score Index (WSI) was considered to classify the severity into mild (WSI < 40) or moderate (WSI 41-60) or severe (WSI > 60) form. This scorecard will help preliminarily to the extent for the identification of the suspected flocks with a required case definition at the first instance, before making decisions on what merits further field investigation. This is first of its kind of methodology to assess the disease pattern in small ruminants and could be used as a disease severity assessment tool in different geographical areas in endemic settings.

Comparative assessment of heat stress induced changes in carcass traits, plasma leptin profile and skeletal muscle myostatin and HSP70 gene expression patterns between indigenous Osmanabadi and Salem Black goat breeds.

The primary objective of the study was to compare the impact of heat stress on meat production characteristics of Osmanabadi and Salem Black breed goats based on changes in carcass characteristics, meat quality attributes, plasma leptin concentration, skeletal muscle myostatin and heat shock protein 70 (HSP70) gene expression patterns. The goats were randomly distributed into four groups: OSC (n = 6; Osmanabadi Control), OSHS (n = 6; Osmanabadi Heat Stress), SBC (n = 6; Salem Black Control) and SBHS (n = 6; Salem Black Heat Stress). The animals were slaughtered at the end of the study and their meat characteristics were assessed. This study established the impact of heat stress on a wide variety of carcass and meat quality characteristics in OS and SB goat breeds. The results from the study also provided some crucial evidence for a better resilience capacity of Salem Black breed as compared to Osmanabadi goats in maintaining the meat production during heat stress. The study also established plasma leptin and HSP70 genes to be the ideal biomarkers to reflect the impact of heat stress on meat characteristics in indigenous goats.

Genetic clustering of recent classical swine fever virus isolates from Karnataka, India revealed the emergence of subtype 2.2 replacing subtype 1.1.

The phylogenetic analysis of 11 CSFV isolates from Karnataka, India obtained during the year 2012-13 was undertaken to obtain the most reliable genetic typing of the CSFV isolates based on E2, NS5B and 5'UTR genomic regions. The study indicated that all the 11 CSFV isolates belonged to subgroup 2.2. The most reliable classification was obtained with sequence data from the NS5B region which separated all the isolates based on the history of outbreak and geographic origin. Analysis of full length E2 amino acid sequences revealed different genetic makeup of Indian 2.2 isolates compared to 2.2 isolates from different countries. The group 2.2 viruses are gradually spreading as confirmed by frequent detection/ isolation of group 2.2 viruses in the recent years and replacing the subgroup 1.1 viruses, which were hitherto predominantly involved in CSF outbreaks in India.