“All diseases begin from the gut”
“While vaccination is available for the disease, it is being imported in Pakistan from other countries. The importation of the said vaccine thus, leads to extra expenses for the farm managers.”
In developing countries where cases of malnutrition are very common in young children and animals, rotavirus has a special importance as an etiologic agent causing calves to scour between five to fourteen days of age. It causes severe diarrhea, when accompanied with severe dehydration, leads to high rate of mortality. Among the rest of the infectious diseases present in calves, neonatal diarrhea is a dire threat as it has a major impact on economic viability. Rotavirus awareness survey depicts that more than half (52 percent) of the mothers of the population had never heard of rotavirus and 28 percent were not familiar or not at all familiar with it. The same is the case with the livestock sector. More than 50% of the farmers in Pakistan are not aware about the viral pathogens responsible for neonatal diarrhea.
The cattle and buffalo calves’ population in Pakistan is devastatingly affected by the neonatal calf diarrhea due to rotavirus outbreaks. Neonatal calf mortality varies from 8.7 to 64 per cent throughout the world accounting for 84 per cent of the total mortality in the first month of age and is particularly high in the third week.
Bovine rotaviruses are members of genus Rotavirus within the family Reoviridae having diameter 70-75 nm, icosahedral and non-enveloped. The genome is double stranded RNA having 11 segments, which encodes six structural viral proteins and six non-structural proteins. Seven groups of rotaviruses are on the basis of VP6. These groups are named as A to G. Group A bovine rotaviruses cause neonatal calf diarrhea, which is economically an important disease of calves causing mortality and is one of the leading factors of a significant economic loss. In neonatal calves, about 5–20% of the mortality rate is observed due to bovine rotaviruses. In calves, average incidence and prevalence of the infection is 30-40%. Three countries in the subcontinent (India, Bangladesh, and Pakistan) account for >30% of all rotavirus-related deaths worldwide. Overall Prevalence of bovine rotavirus infection in Pakistan is 2.6%. Higher prevalence of 3% was recorded in Okara and Rawalpindi districts, but in Lahore 2%.
“The need of the time is to make the general public, farmers and students to educate themselves and their families aware about the transmission of this precarious virus and sue of effective vaccine for public and livestock health.”
While vaccination is available for the disease, it is being imported in Pakistan from other countries. The importation of the said vaccine thus, leads to extra expenses for the farm managers. One of the aims of my study was to develop an effective vaccine against bovine rotavirus and cut down expenses for farm managers.
A series of experiments were conducted at Department of Microbiology, University of Veterinary & Animal Sciences Lahore under the supervision of Prof. Dr. Tahir Yaqub. This study was funded by Punjab Agriculture Research Board, Lahore Pakistan. Almost 200 samples were collected from public/private sector buffalo and cattle farms from 10 districts of the Punjab: Lahore, Faisalabad, Okara, Sahiwal, Sargodha, Chakwal, Bhakkar, Bahawalnagar, Multan and Bahawalpur. The samples were selected on the basis of agro-ecological zones of the province. As sampling based on agro-ecological zones allow for better data collection for recording incidence rate of the disease. A total of 12 rotavirus isolates has been confirmed from collected samples from different districts of Punjab revealing the existence of prevailing strain of rotavirus among livestock population of Punjab, Pakistan.
The bovine rotavirus was isolated and identified using different microbiological techniques, Enzyme Linked Immunosorbant assay (ELISA), Cell culture, reverse transcriptase Polymerase chain reaction (rt-PCR) and genome sequencing. The two antigenic genes VP4 and VP6 were studied for virus grouping and homology depicting the similarities as well as differences of the bovine rotavirus strain present in Pakistani isolates when compared to local regions as well as international ones. The data shows the prevailing rotavirus strain is showing up to 90% homology with that of Indian rotavirus strain. As a matter of fact, RNA viruses are known to mutate unpredictably and it is safe to assume that a particular vaccine might not work effectively against all strains of a particular virus. That’s why analysis of data pertaining to all possible Bovine Rotavirus strains is important for creation of an effective vaccine of import quality in order to help the economy of Pakistan. This important aspect was furnished in the current approach. Rotavirus isolate, after adaptation on MDBK cell line and molecular characterisation was further propagated for vaccine preparation purposes. Final dose of the vaccine was adjusted to approximately 3ml. The field study was done at Livestock Production Research Institute, (LPRI) Bahadurnagar, Okara to evaluate the prepared rotavirus vaccine for prevention of neonatal calf diarrhea. It was observed that the use of killed vaccine for bovines produced more efficient immune response in calves. These results indicated the protective maternal antibody level against the rotavirus which will be transferred passively to calves. The vaccinated dams (Buffalo and Cattle) were able to provide passive immunity to new born calves in order to provide protection against the deadly virus.
The need of the time is to make the general public, farmers and students to educate themselves and their families aware about the transmission of this precarious virus and sue of effective vaccine for public and livestock health.
“All diseases begin from the GUT so protect your livestock, eat healthy and live healthy”
