The backcross is most often used when a particular breed is well suited to the production environment such as indigenous breeds in tropical areas.
(The backcross; is used; T:when a particular breed is well suited to the production environment such as indigenous breeds in tropical areas; T:most often) (a particular breed; is; well suited to the production environment such as indigenous breeds in tropical areas)
The backcross a particular breed
is used is
T:when a particular breed is well suited to the production environment such as indigenous breeds in tropical areas T:most often
well suited to the production environment such as indigenous breeds in tropical areas