the fact that you have had guinea pigs for 48years is very good for a lot of matters, but in these last years things and rules about their diet are totally changed (the same happened for newborns and toddlers... I had to do totally differently even with my second daughter). I hope you are following the latest food rules for your piggies for preventing diabetes caused by too many high glycemic vegs. Of course a piggie 5 years old is a quite old piggie and may develop some disease. But diabetes type 2 has a treatment and sometimes it recovers.
Hazel and Ginger - Diabetes Treatment - Patricia's Guinea Pigs
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1539415/pdf/canvetj00154-0049.pdf
and I would add a supplement of vit C, just for seeing the differences... for a stress, whatever it is, cells need a great amount of antioxidants (vit C for example).
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Moreover:
Burgess Excel contains wheat, beet pulp and molassas... three totally wrong ingredients which boost the insulin on the bloodstream. I agree with these comments below:
By
Roseon 28 September 2016
It is not really good and healthy food for piggies. Vets who recommend it obviously have no speciality in exotic pets. Good guinea pig food should be mostly made out of grasses and herbs. Maize, molasses, alfalfa, soya, really? Don't feed it to your animals
By
PoppyLilyon 19 September 2016
What disappointing me most is the incredibly misleading branding- beneficial fibre is quoted at 36% (wow!) but crude fibre, which I couldn't find anywhere on this listing and what actually matters when selecting guinea pig food, is only 17% (compare this to oxbow cavy cuisine at 28%). The crude protein content also concerns me at 17% which is actually the highest I've found in ANY guinea pig food, debateably dangerously high.
Some of the ingredients are also worrying. Lucerne (alfalfa) content is relatively high, explaining the protein. Lucerne shouldn't be fed at ALL to adults due to the high protein content. There's also sugar beet pulp, a cheap, poor quality fibre known to damage the digestive systems of cats and dogs. Soya oil, soya beans and various grains are also added, which are completely unnecessary for a healthy guinea pig.
Guinea pigs do enjoy it, but it isn't a good food at all and definitely shouldn't be a stable. I urge you to shop around, look at the protein-fibre ratio and chose something that will be food for your pets. Burgess excel definitely isn't it.
By
adrianon 6 September 2016
my guinea pigs love it but it very unhealthy for them. Guinea pigs are not meant to eat grains and seeds and stuff like that. Most of the composition is not suitable for them. It's basically McDonald's for Guinea pigs.