Your best bet would be to feed raw (meat, bones, organs) or home cooked after doing a lot of research, people on this forum can help you a LOT with that. If you must feed a kibble/commercial food, I'd go with one of the Eukanuba brands, if you can find the Eukanuba formula called "pure" I think it's probably the best they have. I do believe that brand is available in South Africa, not sure if it's common or not though.
If you do feed any kibble I'd add meat to it, either just cooked meat or 100% meat canned dog foods if they are available. That will help increase the amount of animal protein a bit.
As far as weight goes, I'd just try feeding less. How much do you feed the dog now?
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