Ancient virus genomes preserved as fossils and carried by host within their genome. Although viral genomes evolve rapidly, their rate of change slows to the same pace as that of the host’s DNA after insertion, making it possible to study viral DNA sequences that are many millions of years old. Paleovirology is the study of viral fossil records typically over prehistoric or geological timescales and the effects that these agents have had on the evolution of their hosts. Viruses sometimes heritably integrate into the genomes of their hosts, resulting in genomic features known as endogenous viral elements (EVEs). Using EVEs, the field of paleovirology investigates the long term evolution of viruses and their impact on hosts. One of the fruitful outcomes of high throughput genomics is the widespread availability of whole genome data, offering the unprecedented opportunity to investigate EVEs at a large scale. This review, highlights the utility of antiviral gene evolution for the study of paleovirology, the consequent surge in paleovirology and the main methodological techniques used to study them. EVEs can only be understood within an evolutionary framework and we outline a generalized workflow for conducting paleovirology studies.

In the environment of the farms, feed, fodder and water could be contaminated with fecal material especially which could constitute a reservoir of Enterobacteriaceae bacteria.Total of 80 fecal samples collected from diarrheic calves, normal calves, diarrheic cattle, healthy cattle and shed of cattle were included in this study. Of which 67 (83.75%) isolates were biochemically identified as E.coli. Among 67 E.coli isolates, 12 (17.91%) isolates were of diarrheic cases (10 isolates from 1 month-6 months calf and 2 isolates from diarrheic cow), 51 (76.11%) isolates were of healthy cows (14 isolates from 1 month-6 months calf and 37 isolates from normal cows), 2(2.98%) from water samples, one isolate (1.49%)each from cow manure and air sample at farm respectively, from cow shed. Eleven (16.41%) out of 67 isolates were found to cause lysis on sheep erythrocytes and 55 (82.089%) out of 67 isolates were found to be biofilm producers on Congo red. Twenty-four (35.82%) isolates out of 67 were positive for bfpA gene, eight (11.94%) for eaeC gene, while five (7.46%) for both the genes of E.coli strain.

Background: Campylobacter species are a leading cause of most important food-borne diarrhoeal illness worldwide while, poultry has been identified as a significant cause of Campylobacter infection in humans. C. jejuni is highly effective in colonizing chicken intestinal mucosa without causing any clinical manifestations and the consumption of poultry meat is the major source of transmission of bacteria to humans. Methods: The total of 19 chicken meat samples collected from retail markets in Chennai were screened by cultural examination, further subjected to phenotypic characterization using biochemical test and genotypic characterization using polymerase chain reaction assay targeting hip O and map A genes. Result: All the isolates showed growth on modified blood free charcoal cefoperazone deoxycholate agar media (mCCDA) and 18 (94.73%) samples showed typical morphological characteristics. The 12 (63.15%) isolates showed biochemical reactions positive. The results from polymerase chain reaction showed that 10 (83.33%) isolates were positive for C. jejuni. This study suggested that, it is essential to investigate the incidence of Campylobacter jejuni infection in poultry and the risk factors at all production stages of meat production to help reducing the disease in humans in terms of food safety.

Background: Campylobacter has emerged as an important zoonotic food borne pathogen of human and animals worldwide. Campylobacter is one of the most common bacterial enteropathogens of food borne origin in industrialized countries with C. jejuni being the most common species followed by C. coli. There are very few cases reported from mastitis therefore this study was aimed to determine the incidence of Campylobacter jejuni from from mastitis milk and raw milk samples. Methods: Total of 72 milk samples comprising mastitis milk (20) and raw milk (52) were collected. The samples were subjected to cultural examination, biochemical as well as molecular identification. The isolates were further subjected to phenotypic characterization by biochemical test and genotypic characterization by Polymerase Chain Reaction. The isolates were subjected to PCR targeting hip O and MAP A genes. Result: The 52 samples showed growth on modified Blood Free Charcoal Cefoperazone Deoxycholate agar media and 18 (34.61%) samples showed typical morphological characteristics. The result revealed that 10 (19.23%) isolates were positive by phenotypic characteristic and 7(70%) by Polymerase chain reaction for C. jejuni. The outcome result showed that importance of Campylobacter jejuni in cattle, especially raw milk and milk from mastitis cows, as a potential source for transmission of Campylobacteriosis in human and dairy farm environment. This can cause acute bacterial gastroenteritis in humans and associated with foodborn infection, food safety and a serious public health threat.

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