If she really has been getting the meals you described, I would be concerned about her ability to utilize feed. I would consult a vet to have her teeth examined, and maybe get a blood analysis. If the grass you have is good quality, that should be a big help. You might also look into a low-starch, high-fat feed to help her gain weight. I'm not familiar with the term "hard meal", unless you mean that the feed she was getting is physically hard. If that's the case, she might need a softer feed, or feed that has been soaked.
Good luck, and keep us posted.
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