Welcome to the Forum. The best things to feed hogs are good quality hedgehog food, cat/dog food, cat/kitten biscuits. Chicken varieties thought to be more easily digestible. Not sure what Webbox chicken roll is. If it is pretty much just chicken, you would be better of feeding cat/dog food, because they probably have added vitamins, etc.
Definitely cut out the mealworms. They do love them, but it has been found that not only can they become addicted to them, but they are bad for them. They have too much phosphorous in relation to calcium and this can cause the calcium to leach out of the bones. Particularly dangerous in hoglets who can develop deformities. If the hogs have become used to the mealworms you may need to reduce them gradually.
The following is a link to a video about Metabolic Bone Disease caused by eating too many mealworms. The beginning is a bit distressing but it is worth watching on to hear the explanation from a vet.
P.S. Please remember to sign the Petition https://petition.parliament.uk/petitions/206274 and if you have already, try to get at least 5 others to sign as well – and pass the message on. Time is running out. Less than 6 weeks left and still a long way to go.
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