You can try replacing this line:

xsl:value-of select="@Body" disable-output-escaping="yes"/>

with

SharePoint:AppendOnlyHistory FieldName="Body" runat="server" ControlMode="Display" ItemId="{@ID}"/>

ControlMode can be changed to Add or Edit as per requirements

You can try replacing this line:

<xsl:value-of select="@Body" disable-output-escaping="yes"/> 

with

<SharePoint:AppendOnlyHistory FieldName="Body" runat="server" ControlMode="Display" ItemId="{@ID}"/> 

ControlMode can be changed to Add or Edit as per requirements