BREEDING FOR PRODUCTION...EGGS AND OR MEAT.

[Beekissed]

I had never heard of high ammonia levels being a cause for egg changes. What is the science behind that?

 

[bnjrob]

Relax. It does not matter who is right and wrong.

The video was posted for the general audience, and not for you. I was typing that as you were posting your response. I am sure that you already knew all that is on the video.

The video does show how blood spots etc. are formed. Did you watch the video? It was done by Auburn University. I think.

I have some commercial textbooks and none mention stress as a candidate. I have only heard it as speculation.

Someone would have to demonstrate to me how stress causes blood spots in eggs, other than physical trauma, in order for me to buy into that stress causes blood spots. Perhaps you are correct. I would just have to see evidence other than speculation to believe it. Could possibly, and actually does is two different things to me. The burden of proof is to demonstrate that stress is a cause.

You assume that I am upset with you. I am not. You have simply not shown me evidence of why you are adamant that some sort of stress is not a cause. You and I both know that for every study out there, you will find one or more studies that contradict the first study. It's up to the individual person to determine what information holds merit and then they can act accordingly . I know what I have found in my research and have made an opinion based on that information, as you obviously have based on your research.

 

[bnjrob]

From my experience, for whatever that is worth, I sort of see blood spots as naturally occurring things that just happen now and again but have no specific origin or cause that can be prevented or noted. If stress was a large factor in it, the battery layers should have blood spots at all times as I can imagine no more stressful life than the one they live. If that were the case, wouldn't that render their eggs pretty nigh unusable for commercial sale other than in pancake mixes and such?

I don't often see them in my eggs but down through the years there have been certain birds that were more prone to throw one or they seemed more evident in an old hen's eggs than when she was a younger layer. I have one such old hen in my flock now and if I get a blood spot at all on occasion, they are always in her eggs. I don't think she had that problem when she was younger or I would have picked up on it, as she has a very distinctive egg color pattern.

If they resulted from mating trauma I think I'd see them more frequently as that is an ongoing process and I usually just have the one male doing the breeding, using the same style and force.

Some of the info I have read regarding the commercial eggs is that some companies will candle the eggs to get rid of those that have blood or meat spots in them. If that is true, then it could account for not seeing them very often in commercial eggs. Or maybe those commercial birds have been bred so long that they can now withstand that kind of stress so it isn't seen in their egg quality like you might find if you put farm chicken into that situation. Who knows?

In the case of what I think you're thinking about in a commercial laying flock, that definition of *stress* caused by small quarters would be closer to using the human definition of being *stressed out* rather than other ways that an organism experiences stress. Stress can be anything that causes a need to readjust and adapt to something - like a change in temperature, weather, not having enough water, being chased, fighting off an illness, trying to heal an injury, not getting the proper nutrition. Stress can be an ambiguous term and what may negatively stress one person or animal may not have the same effect on another.

I think it's one of those things where there's too many variables for them to say what causes the blood spots other than the obvious - that blood leaked through the blood vessel wall, or the blood vessel actually ruptured or was ripped apart. It's the *what caused the blood vessel to leak blood or to be ruptured or torn" question that doesn't have just one answer. Everything I've read on the subject identified *stress* as the most common problem that they have noted when searching for clues to the cause of blood vessel leakage/rupture. Of course the term *stress* is never clearly identified. Probably because there is not one term to identify negative vs positive stress across all chickens.

I'm with you - it happens, and they really don't have an absolute, across the board answer as to what makes it happen for every chicken in every situation. Just gotta look at your flock and see if it happens in birds that are related, thinking that it may be an anatomical abnormality that keeps getting passed on, or if it is some other reason that you may or may not be able to ID and/or fix.

 

[Amina]

Blood spots are largely genetic, and they have been bred to very low levels in commercial (especially white egg) strains. You might find this interesting:
http://www.positiveaction.info/pdfs/articles/hp19.7p7.pdf

 

[Beekissed]

Blood spots are largely genetic, and they have been bred to very low levels in commercial (especially white egg) strains. You might find this interesting:
http://www.positiveaction.info/pdfs/articles/hp19.7p7.pdf

That's an interesting article, thanks for posting it! I'm thinking that the backyard breeder is already~by default~breeding against blood spots as we candle the eggs before incubating them. If one hen has consistent blood spot production, it would stand to reason her offspring are never going to be hatched. I expect that also goes for those that incubate commercially, as they undoubtedly have more sophisticated means than we to candle and eliminate these defects. I'm wondering, on that premise, how one would breed for or against something that one is not going to place in the incubator at all. At that point the blood spot carrying hens would never get to procreate at all and that trait would soon just die out, wouldn't it?

 

[bnjrob]

That's an interesting article, thanks for posting it! I'm thinking that the backyard breeder is already~by default~breeding against blood spots as we candle the eggs before incubating them. If one hen has consistent blood spot production, it would stand to reason her offspring are never going to be hatched. I expect that also goes for those that incubate commercially, as they undoubtedly have more sophisticated means than we to candle and eliminate these defects. I'm wondering, on that premise, how one would breed for or against something that one is not going to place in the incubator at all. At that point the blood spot carrying hens would never get to procreate at all and that trait would soon just die out, wouldn't it?

Some of those dark colored eggs are hard to candle. Even some of our lighter colored eggs have very thick shells and membranes that can make it hard to see sometimes. Then you would also have to assume that everyone that hatches also candles. I know non-serious breeding folks that don't bother to candle. Heck, I don't always bother to candle. And then there would be situations where folks don't know which hen it is. Those could account for passing it on genetically.

We have a couple of hens we bought as chicks, and they have blood spots. The blood spots happened more often when they were young and living with a bunch of overly aggressive cockerels. Once those cockerels were dispatched and the pen calmed down, the amount of blood spots decreased, but did not completely go away. So we knew that the stress of the pen was involved in the problem, but that it was also likely an anatomic abnormality that was genetic. We still see a periodic spot from these hens, but not like it used to be. We have kept them from being breeders to prevent the genetic component to be passed on. But that's how we do things - not everybody has the same criteria for breeder birds that we do.

 

[Beekissed]

I was told that blood spots decrease hatchability. Wouldn't that also work to eliminate birds that carry a gene for that trait? If that reduces the likelihood that a chick will make it to hatch, it would seem likely that a trait like that wouldn't last very long, would it?

 

[bmvf]

The eggs are collected daily. We had below freezing temps since new years day up until this week so we've had frozen yokes from time to time.

I'm thinking I'd like to trap nest and get some data including bloody eggs.

Like I said, I need to come up with a system to grow out these males. It's not hard separating the sexes, but it doesn't get done if I need to rig up a pen for them at the time I need to separate them.

 

[bnjrob]

I was told that blood spots decrease hatchability. Wouldn't that also work to eliminate birds that carry a gene for that trait? If that reduces the likelihood that a chick will make it to hatch, it would seem likely that a trait like that wouldn't last very long, would it?

LOL - well, I've read that about the hatchability too. So you would think that if it was mostly or entirely genetic, then theoretically we should see it VERY infrequently, since the few birds should not be surviving to pass it on.

This says to me that it is still the same as what I've read - there is more to it than absolute genetics or abnormal anatomical structure location and while they can pinpoint various commonalities between birds that have it, there is no one exact answer. Pretty much like everything else in poultry - too many variables.

 

[bnjrob]

The eggs are collected daily. We had below freezing temps since new years day up until this week so we've had frozen yokes from time to time.

I'm thinking I'd like to trap nest and get some data including bloody eggs.

Like I said, I need to come up with a system to grow out these males. It's not hard separating the sexes, but it doesn't get done if I need to rig up a pen for them at the time I need to separate them.

Do you not have permanent housing? All of our birds are housed in large mobile pens, but some are dedicated pullet and cockerel grow out pens. So there may not be birds in those coops all the time, but they are always there for when it comes time to separate the sexes.