My male Mojave has been off feed since AT LEAST November of last year. He's a 2011, possibly a late 2010. His weight when he went off feed was just about 750 grams. All my balls are eating with a vengeance except him, and now I'm getting worried because he's down to 630 grams as of tonight. I've tried f/t rats and mice, I also tried a live mouse and he had zero interest. What other options should I try before starting to worry? He's in the same rack as 7 other balls, husbandry hasn't changed at all so I don't know why the others have kick started their appetite but not him