Ultrastructural studies on buffalo-pox-virus.

The ultrastructural studies on the replication of Buffalo-pox virus (BPV) on the CAM of developing chick embryos has been reported. The earliest viral replication was observed in the form of electron dense granular matrix inclusion (MI), displacing the cytoplasm. The MI consisted of fibrillar structure, scattered electron dense viroplasm, incomplete membranes of unknown origin, subvirions (SV) containing loosely packed granular viroplasm enclosed by a definite membrane and also SV showing electron dense nucleoid of different sizes. The cytoplasmic classical inclusion body (CI) initially contained granular viroplasm enclosed by a membrane and surrounded by a halo. As the CI increased in their size, the loosely packed viroplasm started degenerating and highly electron dense virus particles were formed and finally these CI were left as empty vacuoles. It appeared that maturation of BPV took place in the CI. The pathological appearance of infected cell organelles has been described.