males?

Question
my daughter has recently got 3 young male guineas,  they seem to be fine
together but I am worried with all that I read about Males fighting as they get
older.  My concern is that if they do fight it will be upsetting for my daughter
(and the guineas!) and that if we needed to it would be hard to rehome older
guineas, should we make a decision now to sell these and get girls??  although
my daughter would be sad to do so would it be better in the long run?

Answer
Tilly,

The males should be fine together as you got them when they where young. It is a myth that males always fight. Females fight with females. To make the perfect match for Guinea Pigs it is matching their personalities. So if your males all have close to the same personalities they will be fine. If they are all close to having calm personalities, or relaxed personalities, or such. If you notice that one's personalities that doesn't match the other two then I would look into rehoming him as he'll not get along with the other.

As they get older though you'll start to notice their dominance behavior starting up. It is mostly non aggressive behavior but sometime it can get to be serious. Here is a list of what will happen and what to watch out for in case it becomes serious.

Safe, non-combative, dominance behavior
  
Rumblestrutting
Butt sniffing
Butt nudging
Chasing
Butt dragging (they are leaving their scent)
Mounting (any which way: rear mount, head mount, side mount, flying leap mount!)
Nose face-offs (higher in the air wins, one must lower their nose to be subservient to the other)
Teeth chattering: a little (signal of dominance)
Raised hackles (hair on the back of the neck and along the spine)

Posturing for possible attack, battle for dominance is escalating, but nothing to worry about yet.
  
Teeth chattering: sustained (signal of anger, aggression, warning)
Nips, light bites, may result in little tufts of fur in their teeth
Wide yawn, but this is no yawn, they are showing their teeth
Snorting (like a strong puff or hiss)

These behaviors may sound serious and they should be monitored VERY CLOSELY, BUT do NOT separate the pigs exhibiting this behavior, yet. This is when the average pet owner loses it and pulls the pig out. Most of the time, this behavior will continue for a while until one backs down.

Fighting with intent to harm
  
Bite attacks are no longer warning nips, they are lunges with intent to harm.
Combination of raised hackles, loud and angry teeth chattering, rumblestrutting in place with the head staying in one position while facing the other guinea pig doing the same thing. Usually a signal of a biting attack. But they may back down before they engage.
Both pigs rear up on their haunches, face to face. This is a clear, brief signal of their intent to launch full attacks at each other. Separate if possible before the attack.
Full battle. The pigs are locked together in a vicious ball of fur. This is very serious. Separate immediately, but be careful. Throw a towel over them and use a dustpan or something other than your hand to separate them. Unintended bites from their very sharp incisors can cause serious damage.

The best indicator to watch for on when to separate guinea pigs is the posturing of the nipping and bite attacks. If that gets more serious, that's the time to separate them. If blood is drawn, it's definitely time to stop that session. Hopefully, you can separate your guinea pigs before any serious harm is done.

So as long as they have the close to the same personalities they will be fine. And better yet if they are brothers or where in the litter group they'll be even more likely to get along.

I hope this helps and good luck to you,
        Take care now,
                  Jules