A sheep pox thermostable vaccine was derived from the Kenyan sheep and goat pox
vaccine strain 0240, through utilization of plaque purification to obtain pure virus clones at
37oC. Plaques were then propagated on lamb testis cells (LT). The thermodynamics of plaques
was studied at 56oC for different time intervals, and the one showing the least loss of titre was
selected for vaccine seed development.The thermostable vaccine was placed in the incubator at
37 oC for 2 weeks, together with 3 batches of the conventional vaccine for comparison of heat
resistance. Student - t test result was: P 0.01, in favour of the thermostable vaccine.