new research debunks trad views on nutrition

[U_Stormcrow]

Thank you so much for all the information! Maybe someday I'll feel like I'm feeding my chickens optimally for their health. So much still to consider

Don't let the Perfect be the enemy of the Good.

I certainly don't.

Though I do feel that I've read (and continue to read) enough that I have a good understanding of the tradeoffs I'm making, even if they can't be precisely quantified.

You might enjoy this, too. Its both very general and highly theoretical in making a proposal about how birds balance competing dietary priorities. But very readable.

 

[saysfaa]

Back to the hypothetical hen.
She only eats commercial feed which is available all day and night.
The feed she eats is easily processed and her biology tells her no need to store it because there is always food.
Because it travels through her digestive system at a higher rate than other foods she's likely to feel the need to eat more often over a 24 hour period.
Hens like people also eat out of boredom so she's likely to eat more than the 150 grams recommended by the feed producers.
Taking the what quantity of protein a hen needs a day at the studies estimated high end of say 15 grams, that's still a minimum of 12 grams that is either getting excreted or stored as fat. Even allowing for conversion and processing requirements that's still a lot of protein apparently going to waste when fed at 18%.
There is something wrong here, that's two good medium eggs worth of protein!

How did the feed producers come up with 150 grams? If they based it on studies using hens who had similar conditions - boredom, lack of exercise, always food - then eating more, the food traveling through her system, and so should be factored into the formulation. One could probably tell by whether she actually eats about 150 grams.

 

[U_Stormcrow]

Back to the hypothetical hen.
She only eats commercial feed which is available all day and night.
The feed she eats is easily processed and her biology tells her no need to store it because there is always food.
Because it travels through her digestive system at a higher rate than other foods she's likely to feel the need to eat more often over a 24 hour period.
Hens like people also eat out of boredom so she's likely to eat more than the 150 grams recommended by the feed producers.
Taking the what quantity of protein a hen needs a day at the studies estimated high end of say 15 grams, that's still a minimum of 12 grams that is either getting excreted or stored as fat. Even allowing for conversion and processing requirements that's still a lot of protein apparently going to waste when fed at 18%.
There is something wrong here, that's two good medium eggs worth of protein!

I'm not following your math here, and I'm not certain which feed you are talking about - I can make some generally accurate guesstimates about typical US feeds, but I am MUCH MUCH MUCH worse about making those guesses w/ the common feeds I see used on your side of the pond.

If we get deep enough into the weeds, I suspect we'd find a big difference in the underlying AA balance of the Crude Protein. Most US target diets for adult birds are based on a theoretical 100g/bird/day, not 150g/bird /day. That suggest a much higher nutrient density in typical US commercial feed formulations. We could be comparing apples and oranges.

or my profound lack of sleep could be catching up w/ me. The animals didn't let me get much this week. Apologies if I overlooked the obvious.

/EDIT and it now occurs to me, as I read this, that I should try and get some sleep. I'll drop back into this thread this weekend between erecting lengths of new fencing.

 

[Labsandchickens8]

Don't let the Perfect be the enemy of the Good.

I certainly don't.

Though I do feel that I've read (and continue to read) enough that I have a good understanding of the tradeoffs I'm making, even if they can't be precisely quantified.

You might enjoy this, too. Its both very general and highly theoretical in making a proposal about how birds balance competing dietary priorities. But very readable.

Thank you!

 

[saysfaa]

...
Taking the what quantity of protein a hen needs a day at the studies estimated high end of say 15 grams, that's still a minimum of 12 grams that is either getting excreted or stored as fat. Even allowing for conversion and processing requirements that's still a lot of protein apparently going to waste when fed at 18%.
There is something wrong here, that's two good medium eggs worth of protein!

If each amino acid is fed at the amount the hen needed and no more then much less protein is needed. But food doesn't work that way. Yes, there is more wasted protein at 18%, but the extra 3% gives enough of the limiting factor amino acids to do more of the things needed to keep her actually well instead of just alive.

Concept, here, not necessarily literally so.

I'm more familiar with selenium. How much is enough selenium? One amount is enough if birds aren't stressed; another amount is needed if they are stressed. If they get the amount for non-stressed hens and then get exposed to a predator or parasites or a virus, is it the predator/parasite/virus that kills them or not enough selenium?

Proteins are the building blocks of most tissues, of hormones. It seems possible that just barely enough over a few weeks or even a year of controlled conditions may not be enough over several years or in different conditions.

 

[saysfaa]

.. still a lot of protein apparently going to waste when fed at 18%.
There is something wrong here, that's two good medium eggs worth of protein!

Is any extra going to waste?

It may not be used by the hen but if we take the litter to the garden, it gets used.

 

[Shadrach]

How did the feed producers come up with 150 grams?

I really don't know. I imagine over time that's what they found to be an average over the breeds they studied. The field hens I care for at the moment eat something like 150 grams a day of the feed I provide but it's not commercial feed.
I've seen various feed quantities suggested on feed bags ranging from 125 grams to 200 grams.

 

[Shadrach]

We could be comparing apples and oranges.

We could well be. In more recent studies they suggest that altering the calorific content of the feed (sort of nutrient density) has a greater impact on egg production than the percentage of crude protein.
There is the amino acid profile to take into account and the recommendations for this vary in the studies as do the feed componants used to achieve these numbers.
Back to the video, to suggest that feeding higher protein feed (18% in his view) is a universal solution to chicken nutrition (a bit harsh of a judgement on my part)) seems rather short sighted given the variables that have bubbled up on this thread.
It's just not that simple.

 

[U_Stormcrow]

We could well be. In more recent studies they suggest that altering the calorific content of the feed (sort of nutrient density) has a greater impact on egg production than the percentage of crude protein.
There is the amino acid profile to take into account and the recommendations for this vary in the studies as do the feed componants used to achieve these numbers.
Back to the video, to suggest that feeding higher protein feed (18% in his view) is a universal solution to chicken nutrition (a bit harsh of a judgement on my part)) seems rather short sighted given the variables that have bubbled up on this thread.
It's just not that simple.

I'll have to watch the videos. I'm a proponent of certain AAs at levels normally associated with above minimum recommended CP levels and I'd readily agree that focusing solely on CP is both the wrong measure and like filling your Porsche w good gas but no coolant, oil, transmission fluid, or differential oil. In fact most of the make at home feed recipes I take apart is because CP is the only thing they attempted to think of.

 

[U_Stormcrow]

And sadly, even US feed labels don't often disclose the energy density of the feed, whether AME, AMEn, MKe, or some other measure.