My two new guinea pigs are about 4-6 weeks old. We've had them since Wednesday and all they eat are pellets. I've given fresh veggies and some fruit everyday-twice a day and they will not eat any of it. I've tried hand feeding and they won't hardly even sniff it!! I'm getting really worried about their vitamin C consumption. Is there anything I can do to get them to eat their fresh food or is there something I can do to make sure they're getting vit. C?