I have been applying for moose every year since 1992 except for 1997-2001 when I was stationed outside ND or overseas. I started applying for elk when I got back to ND in 2002. I had always applied for bull or "any" tags. In 2014 I switched to cow for both moose and elk and I drew them both...
As others have said...no chicken based foods is a good start. Diamond Naturals Lamb fixed the exact same problem with our GSP and we add fish/salmon oil and a spoon of cocunut oil too and that has helped.
Our 10 month old GSP started on Diamond regular brand large breed puppy that was chicken based but had some pretty potent gas and it also went right through him. Also had some skin issues. Switched to Diamond Naturals large breed puppy and it is lamb based and it has really made improvements...