Super stupid question....

[tridentk9]

Yes, in-breeding and line-breeding can "bring out" recessive genes much quicker. The genes are already there, it has just increased the odds of those genes showing up by finding their partner. A recessive gene isn't always "bad". Inbreeding does lessen the numbers of genes available in your flock, this can be good if you start out with good chickens or bad if you start out with bad genes. It depends on your goals both intermediate and end goal and how you choose breeding stock within your flock. EVERYONE has "bad" genes by the way. Some of the so called "bad" genes are good if only one is inherited, bad if two. Sickle Cell Anemia in humans is an example of that. Inbreeding and linebreeding also lowers the Major Histocompatabilty Complex (MHC) which basically means increased risks of immune system problems. This leads to increased risks of disease, parasites, etc. Risks of lowered sterilty (both rooster and hen). It does not increase the risk of mutations as that is changing a gene. Inbreeding takes the genes that are already there and doesn't add any new ones.

While great care of your flock is always vital, it becomes even more important when inbreeding. Because it affects the immune system , their husbandry (care, feeding, exposure to disease and parasites, stress) there is also the theory that husbandry will affect their genes (epigenetics). The immune system is one of the areas where most of the studies have shown epigenetics will have an affect.

 

[lazy gardener]

Can you elaborate a bit more about epigenetics? I find all discussion about genetics absolutely fascinating. I wish I'd been able to take a course during my very limited college days.

 

[tridentk9]

T

Can you elaborate a bit more about epigenetics?  I find all discussion about genetics absolutely fascinating.  I wish I'd been able to take a course during my very limited college days.  

I'm the same, I love learning fascinating subjects and to me genetics is fascinating. As I said in another thread- What's not to love? Gambling, high rollers, cool equipment, new discoveries, sexy articles- yep fascinating and exciting.

ROFL- but I was told that epigenetics is not a subject for BYC. Too advanced for anyone to understand and it might be wrong. oh and just not needed for breeding.

Basically, it's the idea that the environment can alter genes. Turn them on/off, cause offspring to have different results than expected from their parents. In mammals most of the studies I've seen have been on the immune system and behavior. The change to the DNA occurs either within the egg or sperm or during gestation. It may or may not continue down through the progeny, some genes reset themselves, some don't. That's the basics, The results are definitely seen in experiments and testing in poultry.

I'm not an expert though, just an interested amateur. I guess you could call me a theoretical poultry breeder I have no plans to breed.

 

[tridentk9]

This is a definition from an article in an on-line Poultry Science magazine. http://ps.oxfordjournals.org/ Some of their articles are free, some not.

Transgenerational epigenetics is becoming more and more important for understanding the variation of physiological responses of individuals to the environment and the inheritance of these responses based on all mechanisms other than the actual DNA nucleotide sequence. Transgenerational epigenetics is the phenomenon that the information of the environment of (usually) a female animal is translated into memory-like responses preparing the offspring. As a consequence, individuals of the next generation may show different phenotypic traits depending whether their mothers were kept under different environmental conditions. This may result in either positive or negative effects on the next-generation individuals, which is different from individuals from mothers that have been kept in a different environment.

 

[LALA13]

WOW!!! You guys are AMAZING!!!! I went to a vet tech school, but learned NOTHING about chickens/birds!! So, to Tridentk9, while the info may not be "needed" for breeding, it makes an incredible read!!

 

[tridentk9]

WOW!!! You guys are AMAZING!!!!  I went to a vet tech school, but learned NOTHING about chickens/birds!!  So, to Tridentk9, while the info may not be "needed" for breeding, it makes an incredible read!!

Thanks- it's awesome to find others with a similar slant to learning. Here's another fascinating find. Though coming from dogs it makes sense. It's only the abstract but it has the important stuff.

http://www.appliedanimalbehaviour.com/article/S0168-1591(13)00265-7/fulltext

Abstract
The purposes of this study were to determine whether rearing with a broody hen influenced duration of tonic immobility, heterophil to lymphocyte ratio, and relative fluctuating asymmetry of chicks and to analyze the differences between broody and non-broody hens in fear and stress indicators. A total of 120 chicks (60 reared with a broody hen and 60 reared without a broody hen), and 48 hens (24 broody and 24 non-broody) were analyzed at 6 and 52 weeks of age, respectively. Broody hens were observed in 12 different Spanish breeds (Blue Andaluza, Black-barred Andaluza, Black Red Andaluza, Black Castellana, White-faced Spanish, Buff Prat, White Prat, Birchen Leonesa, Quail Castellana, Quail Silver Castellana, Red-barred Vasca, and Red Villafranquina), and all the chicks were from an F1 cross between the Black-barred Andaluza and the Black Castellana breeds. Tonic immobility duration was significantly longer (P < 0.0001) in chicks reared without a broody hen than in those reared with a broody hen, suggesting that the presence of a broody hen reduces fear in chicks. There were no significant differences in the heterophil to lymphocyte ratio and the relative fluctuating asymmetry of leg length, leg width, and toe length, although the fluctuating asymmetry of wing length and the combined fluctuating asymmetry value of the 4 traits tended to be significant. These results suggest no effect on stress in chicks in the presence of a broody hen. Tonic immobility duration and heterophil to lymphocyte ratio were similar in broody and non-broody hens, indicating no association of broodiness with the fear and stress levels in hens. In conclusion, the presence of a broody hen during rearing has significant effects on fearfulness of chicks; rearing chicks with a mother being a method to reduce this major behavioral problem. However, broodiness was not associated with fear and stress indicators in hens.

 

[LALA13]

I also appreciate the links as well.....I just got lost on one for a sec!!! The hubby glanced over at what I was reading, said "what the???", as he's shaking his head, and wanders away....I laugh!!!

 

[islandgirl82]

Fellow information junkie here...tridentk9, thank you for sharing!!

 

[tridentk9]

[VIDEO][VIDEO][/VIDEO][/VIDEO]Phew, after the snide comments yesterday directed at me and also the general BYC-er, I was beginning to wonde if the love of learning was absent in poultry owners. I posted an interesting (to me) article on rose comb genetics a week or so ago. Two genes for rose comb, R1 and R2. Homozygous R1 can lower fertility in roosters, , R1R2, R1r and R2r (r is wild type single comb) roosters are normal.
How does this belong in a thread on linebreeding? Linebreeding doesn't add genes, so if you started off with an R1r rooster eventually you may end up with single comb and possibly a reduced fertility rooster. Reduced fertility might not be noticable in a backyard flock or small set up.

But two genes for what was originally (long long ago) a mutation? Awesome

 

[LALA13]

Ahhhh...well....to each their own I suppose, eh? I may be new to this, but, my understanding is that this forum is meant to be helpful to ALL poultry peeps. What may not help one, may very well help another. Some are only interested in what time it is, others want to know how the clocks works. I appreciate all kinds of info.....keeps me well rounded....of course, so do the eggs!!