Genome Sequence of Classical Swine Fever Virus NIVEDI-165, Subtype 1.1, a Field Virus Strain Isolated from the Southern Part of India

Prevalence of porcine viral respiratory diseases in India

The pig industry is growing rapidly in India and contributes a major share of growth in the livestock sector. Over the last few years, there is a gradual increase in the adoption of pigs for production by economically weaker sections of the country. However, this production is affected by many respiratory diseases which are responsible for significant economic loss. The occurrence and impact of these diseases are still under-documented. The four important pathogens including porcine circovirus type 2 (PCV2), porcine reproductive and respiratory syndrome virus (PRRSV), swine influenza A viruses (SIV) and classical swine fever virus (CSFV) are documented here. These diseases are highly devastating in nature and frequent outbreaks have been reported from different parts of the country. The rapid and specific diagnosis, effective prevention and control measures are required for the eradication of these diseases which is urgently required for the growth of the pig industry. This review highlights the prevalence, epidemiology, diagnostics and information gaps on important respiratory viral pathogens of pigs reported from different parts of India. This review also emphasizes the importance of these viral diseases and the urgent need to develop vaccines and effective measures for the eradication of these diseases.

Analysis of codon usage bias of classical swine fever virus

Background and Aim:

Classical swine fever (CSF), caused by CSF virus (CSFV), is a highly contagious disease in pigs causing 100% mortality in susceptible adult pigs and piglets. High mortality rate in pigs causes huge economic loss to pig farmers. CSFV has a positive-sense RNA genome of 12.3 kb in length flanked by untranslated regions at 5’ and 3’ end. The genome codes for a large polyprotein of 3900 amino acids coding for 11 viral proteins. The 1300 codons in the polyprotein are coded by different combinations of three nucleotides which help the infectious agent to evolve itself and adapt to the host environment. This study performed and employed various methods/techniques to estimate the changes occurring in the process of CSFV evolution by analyzing the codon usage pattern.

Materials and Methods:

The evolution of viruses is widely studied by analyzing their nucleotides and coding regions/codons using various methods. A total of 115 complete coding regions of CSFVs including one complete genome from our laboratory (MH734359) were included in this study and analysis was carried out using various methods in estimating codon usage bias and evolution. This study elaborates on the factors that influence the codon usage pattern.

Results:

The effective number of codons (ENC) and relative synonymous codon usage showed the presence of codon usage bias. The mononucleotide (A) has a higher frequency compared to the other mononucleotides (G, C, and T). The dinucleotides CG and CC are underrepresented and overrepresented. The codons CGT was underrepresented and AGG was overrepresented. The codon adaptation index value of 0.71 was obtained indicating that there is a similarity in the codon usage bias. The principal component analysis, ENC-plot, Neutrality plot, and Parity Rule 2 plot produced in this article indicate that the CSFV is influenced by the codon usage bias. The mutational pressure and natural selection are the important factors that influence the codon usage bias.

Conclusion:

The study provides useful information on the codon usage analysis of CSFV and may be utilized to understand the host adaptation to virus environment and its evolution. Further, such findings help in new gene discovery, design of primers/probes, design of transgenes, determination of the origin of species, prediction of gene expression level, and gene function of CSFV. To the best of our knowledge, this is the first study on codon usage bias involving such a large number of complete CSFVs including one sequence of CSFV from India.

Meta-analysis of the prevalence of livestock diseases in North Eastern Region of India

Aim:

The study aimed to determine the overall prevalence of livestock diseases in North Eastern Region (NER) of India, through a systematic review and meta-analysis of published data.

Materials and Methods:

The articles used for the study were retrieved from PubMed, J-Gate Plus, Indian Journals, and Google scholar, R open-source scripting software 3.4.3. Metafor, Meta. The Chi-square test was conducted to assess for the heterogeneity, forest plot (confidence interval [CI] plot) is a method utilized to present the results of meta-analysis, displaying effect estimate and their CIs for each study were used for searching and retrieval of livestock diseases prevalence data in India using a search strategy combining keywords and related database-specific subject terms from 2008 to 2017 in English only.

Results:

The prevalence of various livestock diseases are foot-and-mouth disease (21%), bluetongue (28%), brucellosis in bovine (17%), brucellosis in caprine (2%), brucellosis in porcine (18%), brucellosis in sheep and goat (3%), babesiosis (6%), theileriosis (26%), porcine reproductive and respiratory syndrome (1%), porcine cysticercosis (6%), classical swine fever (31%), Porcine circovirus (43%), and Peste des petits ruminants (15%). This information helps policymakers to take appropriate measures to reduce the disease burden.

Conclusion:

This study indicates that the overall prevalence of various livestock diseases in NER of India.