He has one blue egg gene at that gene pair so about half his offspring will inherit the blue egg gene and half will not. With the brown from the Marans any pullets with the blue egg gene will lay some shade of green.
How old are these three? They mature at different rates so age is not a straight correlation but their relative maturities can have a huge effect on how they interact between each other and with the rest of the flock.
Whenever they hit puberty until they mature out of it. Some cockerels start puberty as early as 12 weeks of age, some wait until 5 months or longer to start. I've had a cockerel behave as a mature rooster at 5 months (only one, that is rare) and I've had one not behave as that mature until 11 months. Others say they have had some go longer. If I had to pick an average I'd go with 7 months but it can really vary by the individual.
I don't find that breed has much to do with it. For example, I once got 20 Buff Rock cockerels to raise one to be my flock master and to eat the rest. Although they were the same breed from the same flock the maturity rates were all over the place.
Sometimes, sometimes not. A dominant male can sometimes suppress the behaviors of the non-dominant ones. Sometimes additional boys can bring out competitions. You are dealing with living animals, you don't get guarantees as to how they will behave. Each one can react differently to the same stimulus. That's part of why I'm wondering how old your young ones are. Your 28 week old is the dominant one now. Things could change dramatically as the others mature.
No direct experience with Orpington, SS, or Marsbar roosters specifically. I'd never heard or Marsbar until this thread but I've had other crosses. In my opinion and experience things like maturity, individual personality, management techniques, and room have a lot more effect on behaviors than breed. If you read enough posts on this forum you will see that some people really like the behaviors of their Orpington, SS, Silkies, RIR's, Barred Rock, or roosters of any other breed while others hate the behaviors of different roosters of these same breeds.
From my experience and from the stories I've read on this forum you can have the same problems or lack of problems whatever the ratio of boys to girls. The boys will fight over 20 girls as fast as they will over 1. You can get bare backed hens, over-mating, and other issues if the ratio is 1 to 1 or 1 to 20.
The more boys you have the more likely you are to have problems so I suggest you keep as few boys as you can and still meet your goals. Things like maturity levels, how much room you have, the individual personality of the boys, and the individual personality of the girls all have more importance than male to female ratio.
Best can mean a lot of different things to different people. We all have different tastes and other goals in regard to meat. Some of us are all about size, for others size isn't that important. Some of us prefer the extra flavor you can get as the boys age while others hate it. The meat can get tougher as the boys mature so you can't cook it as you would a very young one, but there are cooking techniques where the meat of an old rooster pretty much melts in your mouth.
This can vary depending in the individuals and is regardless of breed, but my cockerels tend to grow at a reasonable rate until they are just over 5 months old but they can continue to grow for another year or more. They don't grow a lot, they tremendously slow down. I find it is not worth it to feed a cockerel past 23 weeks if you are trying to add meat. Some of the early maturing ones reach that point earlier.
It doesn't matter what I would do. My goals and personal preferences are different from yours. My facilities and management techniques are different from yours. As far as I'm concerned it has to be your decision.
This is not at all unusual. Mature hens sometimes want the potential father of their chicks to be worthy fathers. Immature cockerels can have a lot of trouble meeting that criteria. That's a big part in why I say the girls have a big part to play in how this goes.
One of my goals is to play with genetics. The way I approach that means I keep several cockerels and pullets each year and raise them with the flock. I typically have a mature rooster (the one I raised the last year) with them until the cockerel I'm keeping is around 6 months old. I start butchering some that I know will not make the grade at around 16 weeks and make my decision of which to keep by 23 weeks. The early decisions are pretty easy and by the time I get to the last 2 or 3 any choice is pretty good. I find that different things can happen as they go through puberty. Each year it can be very different.
1. Things go very smoothly. Very little if any drama. This is actually a reasonably common occurrence. I think a big reason it goes this smoothy is due to the hens having a personality where they can accept the boy.
2. More often there is some drama. The cockerels chases some of the hens and pullets and force them to mate. There is some fighting between the boys but it isn't that serious. None get hurt. I observe but let them go.
3. About once every 3 or 4 years it gets pretty violent. The boys fight a lot among themselves and chase the girls. The mature hens tend to run to the mature rooster as long as he is around when they get chased and let him take care of the boys. In those years I lock about a dozen boys in my grow-out pen until they reach butcher age. I do have my limits.
4. Some years the hens do not accept the boy's dominance. He does not measure up to their expectations for a good father. That could be due to a weakness in the boy's personality or one or more of the hens don't want to be dominated by any male (or any other chicken). I think it is usually a combination of the two. What I typically see in these years is that some or most of the hens accept the boy's efforts to mate but the dominant hen does not. She will knock him off of any hen he tries to mate to show that she is the dominant one. Up to a point he runs away so it does not get that violent. He is afraid of her. But at some point he matures enough that he is no longer afraid of her and fights her. I had one year that went like this. For two days it was pretty vicious between the two, she would run away and he would not chase her but he would not let her near the main flock. I observed but there was no blood or injury so I let them work it out. The risk for injury was there as it was violent, I was ready to intervene if I needed to. After two days they settled it and became best buddies but it could have ended differently.
Not always but I try to for two reasons. One of my goals is meat. I find that an early maturing cockerel generally means they get larger at an earlier age. After a couple of generations of breeding I tend to get more meat earlier on with less feed.
I also find that the earlier maturing cockerel often has a stronger personality when compared to a later maturing cockerel. That means he is more likely to win over the girls based on strength of personality. The later maturing may need to rely more on brute force to win the dominating position of flock master and that is usually at an older age. It doesn't always work, some can be brutes, I don't always get it right. Some years the ones I have to choose from aren't as good as other years or I just get it wrong. With living animals I can't give guarantees. I just try to do the best I can and eat my mistakes.
