Volume: 52 Issue: 3
Year: 2021, Page: 250-256, Doi: https://doi.org/10.51966/jvas.2021.52.3.250-256
Received: Feb. 15, 2021 Accepted: March 31, 2021 Published: Sept. 30, 2021
Porcine circovirus associated diseases (PCVAD) caused by porcine circovirus type-2 (PCV-2) are emerging viral diseases with unfavourable effects on animal health and swine economy. We have a lot of information regarding the changes in the lymphoid organs and spleen in PCV-2 infected pigs whereas the reason for anaemic changes in the carcasses and the pathological effects of PCV-2 in bone marrow are still not well studied. Hence, an extensive study to identify the changes in myeloid and erythroid cells of bone marrow in PCV-2 infected pigs was carried out. Myeloid and erythroid series of cells were counted and analysed from the freshly collected bone marrow cytological smears from the PCV-2 suspected samples. Later, PCV-2 infection was confirmed by polymerase chain reaction (PCR) and characteristic histopathological findings. The PCR yielded an amplicon of ~ 481 bp product and those positive cases were selected for determining the Myeloid to Erythroid ratio (M : E ratio). However, values did not significantly differ in any of the cellular components between PCV-2 positive animals and PCV-2 negative animals which indicated that the bone marrow was not the specific target organ for PCV-2 viral infections. However, increased lympho-histiocytic and plasmacytic infiltration was noticed in both lymphoid and non-lymphoid organs. These characteristic features of PCV-2 infection could be considered as a major reason for increased proliferation of myeloid cells.
Keywords: PCV-2, polymerase chain reaction, bone marrow M: E ratio
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© 2021 Vijayaragavan et al. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Vijayaragavan, S., Balakrishnan-Nair, D.K., Sajitha, I. S., Priya, P. M., Anoopraj, R., Devi, S.S., Ravishankar, C., Divya, C. and Saifudeen, S.M. 2021.Myeloid to Erythroid (M: E) ratio in the evaluation of bone marrow cytology of Porcine Circovirus type 2 affected pigs. J. Vet. Anim. Sci. 52(3): 250 – 256. DOI: https://doi.org/10.51966/jvas.2021.52.3.250-256