Plump piggie and slim piggie

[WhiteCatmas]

Hello!
I have two guinea pigs, boars one who is a year and a half, one who is just under a year.
Guinea Pig A rules the cage, keen on humping and rumble strutting. He is older but has always been keen to throw his weight around.
Guine Pig B was bought from Pets at Home as a baby and is the sweetest natured boy. Very calm, lovely.
GPB grew very quickly and was an amazing size, he was nearly as big as GPA. Then I noticed GPB was quite thin. He seems quite cowed by GPA.
I feed them now in two piles, they have a big hay bed, lots of treats and fresh veggies. GPB remains thin.
I’ve noticed GPA claiming the food by almosy humping it. Could he be putting GPB off?
They have a large C&C cage with two levels but their lives are quite dull in winter.
I’d like to see GPB back up to full form. He seems happy and fine otherwise I would have taken him to the vet.

Oh , I love boars they have great character .

If your two boys have unlimited hay then both should have enough to eat . BoarB won't be put off eating by his cagemate frottering in the hay , these animals eat/pee/poo/sleep in hay (they are manky !)

Boars will generally live happily with enough space and food , and places to take themselves off to if they want Time Out .
We had an older smooth and a piglet (Rex) . As the Rex grew he was huge and did try to bonk the older one They had a huge haybox (3'x3') filled to the roof with fresh hay and we gave them a hegdehog house (wicker with a tunnel door) which the older one claimed and the younger one didn't go into .

Though one thing jumps out at me . If your little boy was tubby , now thin Think Teeth .
Guinea pigs will scoff fairly constantly but a sharp or overgrowth back tooth/spur can cause a mouth sore
You can see his front teeth ok , Check his inscisors for length , any breaks
Check his face for any injuries
Your vet will need to check the back ones (ours used a lighted scope , pigs have very narrow little jaws )

Ooo thank you! I wil check his teeth!

My sister has 2 boars , one large and looks like a crossbred beaver , the other is small and very rodenty - the small one started really bullying big pig despite having a huge cage with different food areas , houses and 2 water bottles so they now live separately but next door so can have a chat without having to get on . Everybody seems much happier .

I would do as Floralnomad suggests btw, I had a similar situation with my first pigs (was inexperienced) and the non dominant pig sadly died suddenly :( I believe how that the food hogging caught up with him, as prey animals they hide illness and because I was a new owner I didn't pick them up much, just stroked their heads while feeding etc.