My roosters are about 4 months and neither of them has started crowing and none of them have tail sickles.

[ej1222]

Are you sure they are all males.

 

[Chicalina]

I had one chick I wasn't 100% sure about, so I looked underneath his saddle feathers and found these tell tale signs growing in.

 

[ej1222]

Are you sure that they are four months?

 

[ej1222]

 

[Chuckenman]

Are you sure that they are four months?

They should be about four months, the photo of the leghorn i sent asking for his age was on april 24, y'all said that in that pic the leghorn is about 4 weeks, 1 month. Its july 26 so now they should 4 months. And yes im confident they're all males.
Current pics, taken today
Mix

Australorp

Leghorn

As for the saddle feathers the Australorp is getting some very small light olive feathers on his back just above his wings joint and under his neck. Don't know if they're the ones you're talking about though.

 

[Chicalina]

They all look a bit scrawny and behind to me for 4 months, both in body shape and feathering.

What are you feeding them?

 

[Chicalina]

By way of comparison, these barnevelders of mine are 9.5 weeks old and are the SLOWEST maturing birds I've got. But their feathering and body shape is way more developed than yours are at 4 months. Just an observation in case you need to boost their diet with more protein, or deworm them, for example.

 

[MadamContrary]

Definitely something going on, if I had no other context I would guess they were 7-8 weeks old.

 

[Chuckenman]

Im giving them cracked corn, i bought some broiler feed for them but they didn't eat it all, they tried to but it fell out of their beaks. I made the feed in a powder but they didnt eat that at all

 

[Demonwolf37]

Im giving them cracked corn, i bought some broiler feed for them but they didn't eat it all, they tried to but it fell out of their beaks. I made the feed in a powder but they didnt eat that at all

They definitely need some form of complete feed as their main source of food. Cracked corn should probably only be a treat or thrown in the yard to give them something to scratch for.

I'm not sure what the nutrient values for broiler feed is. Personally I use grower feed for all my teen+ birds and offer oyster shells for the layers.

Try switching their diet to completely broiler or grower feed for a bit and see if they'll eat it consistently. They're definitely missing some nutrition needed to fill out completely and grow.