You get the feeling this will take quite a while to fully recover.
As Big Richo has stated, I would expect Dusty to be up and about come the season start, and would not be surprised to see him a little trimmed down during early pre season but he will no doubt increase his protein intake as his kidney function improves with healing thus assisting him to put mass back on and regain strength.
Kidney trauma is no simple thing, as the kidneys are an amazing and complex organs which perform many functions from assisting / maintaining systemic blood pressure regulation via hormone release to control fluid levels in the body and helping to balance the bodies PH via metabolism and regulation of electroloytes, filtration of proteins and associayted byproducts, hormone secretion and production, red blood cell formation via erythropoetin (EPO) prodcuction in the adrenals and adrenalin / cortisol,in a response to the bodies sympathetic nervous system requirements, and obviously the production or urine from metablic waste in the bloodstream.!
Dusty's weight loss and fruit and veggie diet and renal injury all go hand in hand and are normal par for the course in a patient that has suffered renal trauma.
His diet is simply to minimise protein intake and relieve stress workload on his kidneys by creating a more neutral environment without high levels of protein, albumin's, amino s, creatine, Uric acid and Nitrogen.
Dusty will also suffer a degree of muscular atrophy as he is not taking in protein, or indulging in heavy physical training to maintain his mass, much in the same way as a broken leg muscle atrophies or shrinks.
Renal failure patients are also often placed on such a diet to assist recovery of function if possible.
Animal; proteins contain high amounts of amino acids proteins and substances like creatine, and create by products Uric acid, Nitrogen, which produce acidity in the body and put a bit of work on the kidneys to not only process these substances but also to regulate the changes to help keep the body in a more balanced state.
The body does not heal as well under duress but more to the point that such metabolites create increased workload on the kidneys, and in Dustin's case thats not ideal.
The flip side is that the body needs protein to re build and heal, thus a very delicate balancing act in assisting his recovery.
By limiting the high protein diet the kidneys workload is lessened and the recovering kidney can heal and the good kidney can easily do the work of 2 when not being flogged.
Apologies for the ramble.