There are many different dried food that commercial made for insectivore bird but none specifically made for white-rumped shama. In Southeast Asia where this species is native, bird keeper usually made his own special mix of dried food for the shama beside feeding live wild caught insects. Specific ingredients and amount is often kept secret or varies depend on the keeper. Basically, roast broken rice under low heat until it turns somewhat dark yellowish, but do not let it turns brown. Take chicken egg yolk (no egg white) and mix with roasted broken rice. Slowly roast the mixture again until dry and then can feed to the bird along with daily live foods. Some people want to add roasted peanut, roasted corn, and/or sun dried shrimp, fish, or insects to the mix. If they want to feed the bird dried food in powder form, then put everything into the food processing after roasted each ingredients separately or if they want to feed the bird pellet form, then adding egg yolk last to the mix powder and use meat grinder machine to make pellet form.
As for myself and many hobbyists in the State, commercial dried insectivore food is the best choice to use to feed our bird as most of us didn't know the exact formula or too much time consuming to make one. Mazuri Insectivore and Orlux Insect Patee Premium are the two popular dried food choice as both food have high crude protein level (around 28%) and provided variety of vitamins. Some people also import/buy dried food from Asia and mix with whatever ingredient that they feel will help the bird. I have tried both of the dried food above but since I only keep bird for about a year, I can't tell which one is better than other; however, according to one of the best friend/mentor of mine in bird keeping, Orlux Insect Patee Premium mixed with dried cook chicken egg yolk yields good result with good song performance and tail length in bird which is the method that I also use. Mazuri Insectivore also gives satisfactory result but since I want to add more ingredients to the dried food (to somehow try to make a perfect dried food for shama), Orlux Insect Patee Premium is the better choice for me. During the course of bird keeping since last year, I also mix the Orlux/egg yolk powder with Mazzuri pellet, fish food pellet, and powder grasshopper. Combination with feeding variety of live foods and gutload the crickets/cockroaches with the same bird food and dog food, the result is good in term of increase tail length on the second molt of H1N1 but so far I'm still not completely satisfied as I notice most of my bird are reluctant to eat dried food (except the Hwamei which eat like pig :) ). My friend who feed his birds with the same dried food (minus some of the extra stuffs I add in) and all his birds are eagerly to eat dried food with large amount. Maybe with those extra stuffs that I added in cause the food to have different/funky smell which the bird didn't like? Come to think of it, I think so!
Recently, I found a place to sell freeze dried silkworm pupae which use to feed to koi fish. According to online sources, freeze dried silkworm pupae has min crude protein of 55.3% , min crude fat of 32% (I know the live food composition table in previous post listed silkworm only has 9.6% protein which I believe is true protein percentage, not crude. Crude protein is total protein of a feed includes true protein and other nitrogen containing substances such as ammonia, amino acids and nitrates). When I mix 1:4 ration of freeze dried silkworm pupae to Orlux insect food, suddenly all the shama eat dried food with joys. I think the smell of dried silkworm powder makes the dried food more tasty. Hopefully with extra protein added to the dried food, it can help to keep all the bird in healthy state.