Sustainable Breeding Group Size for a Variety - Thoughts? Opinions?

[Michael Muenks]

I've been pondering the appropriate number of females and males one would need to keep in order to forestall any unfortunate events and to maintain a healthy population of birds. I'm not necessarily thinking about shipping eggs/chicks as the bases for the question, but more from the point of just a healthy number of birds for a variety. My long term thinking has been around 10 females and 4 males of various ages, but I'm interested in what others think.

[Suki]

A rather apropos comment after the flurry of responses on the APA members list on Facebook.  I am not sure you saw it as I don't know if you are a member.  Maybe you are just intuitive because you are breeding again and realize that is a good topic.  Well, the poster on FB felt that without FIFTY birds in a block, she was a loser.  She could not go forward.  I didn't respond, because I've been thinking about it, though plenty did and it was a long thread.

In short, I think a 50 standard flock is too big.  Maybe at breeding season with the chicks but not going into the fall, or at least the next spring. 

The biggest problem as you point out is the issue with inbreeding and how then the flock goes infertile.  I experienced that first hand when I bought a flock of birds from an experience breeder and he wanted to know who breeding was going?  Gee whiz.  What could I say?  I bought 20 birds, and I think two girls were layers and most of the boys duds.  One that he called his breeder did little and the chicks hatched were weaklings.  So that is a problem of locking yourself into a breeding program. 

Back to your question How many do you need?  Well another guy I wrote to, and this was years ago, who posted on the APA site, told me you needed several generations and two separate lines.  So if you start with a trio you need at least two trios and work within that for 4 years and then switch the males.  I've mentioned this another breeder, in bantams btw that is a big winner -- she lives near my family in MA so we met at a local show up there -- and she felt 3 lines was the key.  She did that for 10 years before having to outsource, but she felt in the end you had to outsource because closed flocks were deadly .i.e. infertile.  I went with the two separate line method, but to be honest  finding a solid second line is problematic, at least for me it has been.

Happy holidays, Sue.

[John W Blehm]

I've been pondering the appropriate number of females and males one would need to keep in order to forestall any unfortunate events and to maintain a healthy population of birds. I'm not necessarily thinking about shipping eggs/chicks as the bases for the question, but more from the point of just a healthy number of birds for a variety. My long term thinking has been around 10 females and 4 males of various ages, but I'm interested in what others think.

At first glance I thought you were talking about the ratio of cocks to hens in a flock mating, so I'll get that out of the way and say between 7 and 10 females to one male at a time.  I recommend rotating at least two males over a flock of females to help with both fertility and genetic diversity.  Those numbers then help in figuring the minimums you ask about.  Even with using your best two males for breeding, I've found one may die so I recommend keeping a backup male even if you don't use him...just in case.  Unless you have a really big flock with maybe close to 100 birds of the same variety, I recommend keeping at least two lines of each variety where siblings aren't bred together.  The one can be the flock of 7 to 10 females, with 3 males and the other could be as small as a pair mating.  Name them line A and line B, or whatever, and each breeding season put males from A over females from B and visa-versa.  This type of line breeding without close inbreeding can go on without outcrossing to someone else's line.   
   
Terminology

Linebreeding is the tool most often used by breeders.  Linebreeding is mating "first cousins, nieces with uncles, grandparents with grandchildren and so on" within a line or stain.  Keep in mind definitions may vary and even though Inbreeding can be seen as close Linebreeding generally think of Linebreeding as somewhere between Inbreeding and Outcrossing.

[Suki]

At first glance I thought you were talking about the ratio of cocks to hens in a flock mating, so I'll get that out of the way and say between 7 and 10 females to one male at a time.

The judge Christopher McCary was discussing his turkeys on the APA list and he went with 5. Most I've met and discussed this with felt that the upper limit, so your 7-10 is quite large.

[Michael Muenks]

Thank you for the replies. You have helped me hone me question a bit. I thinking about how many birds one would keep in a variety in order to have a sustainable population to work with. Whether you use pair matings, trios, clan/spiral, flock and any of the other types of breeding systems/plans . . . How many birds do you keep as your core group of breeders?

[John W Blehm]

At first glance I thought you were talking about the ratio of cocks to hens in a flock mating, so I'll get that out of the way and say between 7 and 10 females to one male at a time.

The judge Christopher McCary was discussing his turkeys on the APA list and he went with 5. Most I've met and discussed this with felt that the upper limit, so your 7-10 is quite large.

The heavier breeds use lower ratios.  An article, The Best Mating Ratios for Poultry: How Many Hens per Rooster? on Cackle Hatchery's site, by Gail Damerow mentions 4 to 1 for Bronze turkeys and as much as 12 to 1 for "lightweight and extremely active" Leghorn chickens.  The 7 to 1 and up to 10 to 1 ratios for Ameraucana chickens were my recommendations based on what I read decades ago and experience.

[Suki]

Thanks John for the updated information.  Based on that Michael could span from 5  to 10  hens per male.  I keep about 4 hens per male, but some of those do double time under a male.  I think for Michael the issue is how much space do you have?  Can you have 10 hens for a variety?  And then of course there is the feed aspect.  Some can get their feed a lot cheaper than I.

Suki

[John W Blehm]

Thank you for the replies. You have helped me hone me question a bit. I thinking about how many birds one would keep in a variety in order to have a sustainable population to work with. Whether you use pair matings, trios, clan/spiral, flock and any of the other types of breeding systems/plans . . . How many birds do you keep as your core group of breeders?

I can't prove it from experience or controlled breeding I've read about, but I believe that two pairs is the minimum number that may provide a sustainable population to work with...more would be better, like 4 pairs or more.  A few years ago I had 4 or more "lines" of bantam buffs in 4 coops in a row, A, B C, & D, as I recall.  Any really nice pullets that hatched from line went into that line's coop to breed from.  I kept about 6 females in each coop, so hens that weren't as good were removed to make room for better ones.  The best cockersls from A went over the females in B, The best cockerels from B went over the females in C and so on.  I should have continued with this form of line breeding, but wanted to downsize and sold the bantam condos I was using. 
This season for LF lavenders I'm only breeding from 2 pairs and for LF blacks I'm using just 4 pairs.  These were the best of the best after sorting thru the growing birds from day-old to deciding which to ultimately breed from.     

[Michael Muenks]

Thanks John for the updated information.  Based on that Michael could span from 5  to 10  hens per male.  I keep about 4 hens per male, but some of those do double time under a male.  I think for Michael the issue is how much space do you have?  Can you have 10 hens for a variety?  And then of course there is the feed aspect.  Some can get their feed a lot cheaper than I.

Suki

Suki,

You are heading the direction I had intended orginally with my question, but I was maybe being a bit philosophical with a sprinkle of practicality in my question. I'm working with a barn loft that is 32'x24' and I'm thinking about breeding pen layout and breeding system plans so that I build a pen layout that fits breeding plan.

I am strongly considering a clan/spiral system for a breeding plan as described by John in his post, but I may continue the flock system I used previously.

One of the things I have experienced in the past is "if I only had a couple more pullets/hens" or "I really could have used a couple more cockerels" when something happens like a back up is lost and the primary isn't doing his job or late in the growing out phase color leakage shows up. Just a couple of examples.

Over time, I've basically come up with 10-12 pullets/hens and 5-6 cockerels/cocks as being pretty safe . . . but I've been wondering if that really is a good number when has gotten past the start up years with a variety.
 

[Mike Gilbert]

Michael, for long term sustainability - assuming you wish to keep a closed flock which may or may not be the case - a well known Brown Leghorn breeder I happen to be Facebook friends with claims you need to keep at least 20 females and 8 to 10 males.    I can't do that, given my facilities and the number of varieties I keep.   So I have abandoned the idea of closed flock, and have over the years developed a system whereby other breeders, some close, some far away, keep the same strains so we can help each other out when needed.   I'm currently doing that with Jeff Sonsalla, and have in the past done it with John, Bob Walchak, and others. 

[Michael Muenks]

I've seen several suggestions that partnering with other breeders is a good way to basically keep a "closed flock" concept or a clan/spiral program going. You are lucky to have someone relatively close to you.