Feed management for weaners

In India, there is very little information about professional management of a pig farm. Within this macro deficiency, there is acute absence of information on feed and disease management. Seeing the growth rate of piglets worldwide and comparing them to my recently started farm operations, i feel that i am not doing just enough. I need some help in factoring feed management for weaners, growers and finishers. My piglets are all growing and glowing till they are weaned away. thereon, some of them do well but most are suffering. Kindly help with elaborate intakes for different groups. regards