new research debunks trad views on nutrition

[U_Stormcrow]

That is interesting - particularly the protein.
My chickens, and one in particular love eating grass. But they seem quite selective about what kind of grass and when.
A clumping type grass that they ignored in the late summer - so much so that I had to hack it down - is now being intensely grazed by my ladies.

Juist be aware that they switched to % dry weight when talking about protein. Grass is not really 16%-28% protein. They are saying that once you elminate the average 83% water content, 16-28%, but perhaps as low as 11-12% of the 17% that's left is protein.
IOW, compared to your 16-20% protein commercial ration, grass clippings are 1.87% protein to 4.76% protein. I.e, not a significant protein source. WHat protein it has is in a ratio of about 4:12:10:5 for the big four - Met /Lys / Thre / Tryp (Timothy), generic "grass" is about 4:12:11:4 (source: Feedtables)

If you are into "ideal protien ratios", which is a bit more retentive than I tend to be, the ratio is about 3:7:5:2 for adult layers. Its different for broilers, of course. And different for adolescents of all types.

 

[RoyalChick]

Juist be aware that they switched to % dry weight when talking about protein. Grass is not really 16%-28% protein. They are saying that once you elminate the average 83% water content, 16-28%, but perhaps as low as 11-12% of the 17% that's left is protein.
IOW, compared to your 16-20% protein commercial ration, grass clippings are 1.87% protein to 4.76% protein. I.e, not a significant protein source. WHat protein it has is in a ratio of about 4:12:10:5 for the big four - Met /Lys / Thre / Tryp (Timothy), generic "grass" is about 4:12:11:4 (source: Feedtables)

I did realize about the dry weight and separately had been noticing that on days my chickens eat mainly forage they go to bed with simply enormous crops compared to a day when they are confined and eat mainly commmwrcial food.
That is just an impression - I have not put a tape measure to them - but I was speculating that the commercial food was more nutrient dense so they didn’t have to pack it in the way they do when they are rootling around for stuff.
Help me understand the ratios part. What ratio does a chicken want to aim for (if you see what I mean)?

 

[Painted Calls]

I guess I was lucky with dogs, cats, and horses. All were pretty much free fed and we never had issues. But I wonder if it's because they all lived in a pasture or outside setting. Alot of things over eat or over indulge because they are board including us humans. They all got worked every day. Work includes play too. And when they are pastured with others they tend to make their own fun and food isn't the pacifier it would be with out all that stimulation.

Just a thought and observation of my own animals that I've had throughout the years.

My horses live out on pasture 24/7. In the spring and fall they have to be penned up due to sugar content in grass. They're easy keepers - even at 16, 20, 22, and 26 years old. They cant handle the rich forage. If I left feed out 24/7 they'd all be dead in 3 days. Easy keepers or not.

I think some horses are just prone to IR and founder if left unmanaged and able to graze at will.

 

[Painted Calls]

I think on the grasses the chickens like to eat it's the new shoots. When I move stuff in the yard around and I unearth some young grass shoots they devour them. Older tougher grass is of no interest.

I've found the same. They also love the seeds when it first goes to seed.

 

[Bhubbard]

Well there you go. You are offering the right hays for the ratio to be correct. Alfalfa, as I’m sure you know, does wonders for animals.

Correct it’s good stuff for sure!

 

[Vadard]

According to Tim Spector, Food for Life: the new science of eating well, Jonathan Cape 2022: xiv
Myths that have benefited the food industry and which we should now dispel include: all calories are equal, low-calorie foods are good, high-fat foods are bad, artificial sweeteners are healthy, high levels of processing are harmless, and food and vitamin supplements are as good as real food.

Spector is Professor of Genetic Epidemiology at King's College London, and honorary consultant physician at Guy's and St Thomas' hospitals. These are all world class institutions. He is writing about human diet and nutrition, but much of it applies to chicken diet and nutrition too.

For example, that UPFs (ultra processed foods) made up of many chemicals make us feel hungrier, over-consume, and increase risks of disease and earlier death. This applies to chicken feed pellets, which are specifically designed to achieve the first two, and don't care about the last two because the chickens that they are designed for are not intended or expected to live very long.

I do not expect those BYCers who trot out their tired dogmas on food, feeds, and fats, at any and every opportunity, to stop doing it, but their views are now being labelled as myths by people who really know what they're talking about, and have extensive evidence to prove it.

And the chicken feed industry is catching up with the human feed industry on these matters, so attempting to dismiss it as irrelevant won't wash either.

Regarding the ultra-processed chicken feed pellets: Can you recommend some options that are at least minimally processed? I’d love to grow my own feed one day, but I’m years from that.

The closest I’ve ever seen to locally milled and minimally processes was when I lived in another state years ago. There was a local mill that would sell to local feed stores.

ETA: Nevermind, I see that we are in different countries. I’m sure the feed sacks differ on each side of the Atlantic.

 

[U_Stormcrow]

I did realize about the dry weight and separately had been noticing that on days my chickens eat mainly forage they go to bed with simply enormous crops compared to a day when they are confined and eat mainly commmwrcial food.
That is just an impression - I have not put a tape measure to them - but I was speculating that the commercial food was more nutrient dense so they didn’t have to pack it in the way they do when they are rootling around for stuff.
Help me understand the ratios part. What ratio does a chicken want to aim for (if you see what I mean)?

The ratios are basically for people "in the know", or for math heads, to be able to quickly compare protein qualities (as opposed to protein quantity)

Long ago, someone asked, in essence, what is a "perfect" protein for chickens? That is, a protein that would be completely used, without waste. They called it "ideal". Now because they started asking this question before sulphur containing amino acids (SAAs) could be easily measured, the Ideal protein is often expressed as a ratio to Lysine. For our purposes, Met is often more important (almost always), but Met is an SAA, so we are stuck with Lys ratio, which is why I usually rewrite it as seen above.

So, here's how it works. (some rounding involved) 1 lb is about 454 g. We'll going to round down to 400 (I understand 100g/day is the thumb rule in the EU). An adult hen, it is said, will eat about 1/4# daily (100g). From that ration, it needs to hit a minimum of .3g of Met (you can find studies saying about the same). Based on the 3:7:5:2 ratio, it also needs to hit .3/3*7 = 0.7g Lysine, .3/3*5 = 0.5g Threonine, and 0.3/3*2 = 0.2g Tryptophan. If it does that exactly, its said to be "ideal", there is neither deficit nor excess.

Now, lets say you are going to try and meet your amino acid ratios purely with generic "grass". Generic Grass, per Feedipedia, has a ratio of roughly 4:12:11:4. 0.3 (the Met target) divided by 4 (the Met Ratio number) times 12 (the Lys number) = 0.9g Lysine. Meaning you've exceeded your Lysine target, the excess is likely largely wasted. x11 (the Thre Number) is 0.825, again, there is excess Threonine. and x4 = 0.3g Tryp, about 50% more than is needed, the rest is likely excreted as waste. Lets THEN pretend that you knew that only about 1.4% of the total protein in (generic) grass was Methionine.

You could then figure out how much grass a chicken would need to eat to meet its daily Met Requirement. Assuming your grass was 20% protein (as a percent of dry weight) and was 83% moisture, you are getting 3.4g of total protein per 100g of grass clippings. 1.4% of that is Met 3.4 x .014 = 0.0476g They need 0.3g, a bit more than 6.3x more than was found in 100g of average "grass". So a chicken COULD meet its Met needs by eating 630g of average "grass" in a day. or 1.4# +/- of grass a day !!! If you had that droughty, low protein grass, it would be almost twice that. We could also calculate how much waste Lysine, Thre, and Tryp would be excreted, mostly in the form of nitrogen (meaning ammonia, among other things), but that's really most important to commercial waste management - which is part of why I don't pay much attention to ideal proteins.

 

[RoyalChick]

The ratios are basically for people "in the know", or for math heads, to be able to quickly compare protein qualities (as opposed to protein quantity)

Long ago, someone asked, in essence, what is a "perfect" protein for chickens? That is, a protein that would be completely used, without waste. They called it "ideal". Now because they started asking this question before sulphur containing amino acids (SAAs) could be easily measured, the Ideal protein is often expressed as a ratio to Lysine. For our purposes, Met is often more important (almost always), but Met is an SAA, so we are stuck with Lys ratio, which is why I usually rewrite it as seen above.

So, here's how it works. (some rounding involved) 1 lb is about 454 g. We'll going to round down to 400 (I understand 100g/day is the thumb rule in the EU). An adult hen, it is said, will eat about 1/4# daily (100g). From that ration, it needs to hit a minimum of .3g of Met (you can find studies saying about the same). Based on the 3:7:5:2 ratio, it also needs to hit .3/3*7 = 0.7g Lysine, .3/3*5 = 0.5g Threonine, and 0.3/3*2 = 0.2g Tryptophan. If it does that exactly, its said to be "ideal", there is neither deficit nor excess.

Now, lets say you are going to try and meet your amino acid ratios purely with generic "grass". Generic Grass, per Feedipedia, has a ratio of roughly 4:12:11:4. 0.3 (the Met target) divided by 4 (the Met Ratio number) times 12 (the Lys number) = 0.9g Lysine. Meaning you've exceeded your Lysine target, the excess is likely largely wasted. x11 (the Thre Number) is 0.825, again, there is excess Threonine. and x4 = 0.3g Tryp, about 50% more than is needed, the rest is likely excreted as waste. Lets THEN pretend that you knew that only about 1.4% of the total protein in (generic) grass was Methionine.

You could then figure out how much grass a chicken would need to eat to meet its daily Met Requirement. Assuming your grass was 20% protein (as a percent of dry weight) and was 83% moisture, you are getting 3.4g of total protein per 100g of grass clippings. 1.4% of that is Met 3.4 x .014 = 0.0476g They need 0.3g, a bit more than 6.3x more than was found in 100g of average "grass". So a chicken COULD meet its Met needs by eating 630g of average "grass" in a day. or 1.4# +/- of grass a day !!! If you had that droughty, low protein grass, it would be almost twice that. We could also calculate how much waste Lysine, Thre, and Tryp would be excreted, mostly in the form of nitrogen (meaning ammonia, among other things), but that's really most important to commercial waste management - which is part of why I don't pay much attention to ideal proteins.

Gotcha.
Thanks for explaining that. I am a bit if a math-head so I think I am clear on how the ratios are expressed.
It sounds like methionine is the aa most likely to be deficient in a diet with a lot of grass (maybe any green veg based diet?).
This may be why mine stuff themselves with grass and then come and top up with leftover cat food!

 

[U_Stormcrow]

and of course eating all that grass in order to reach that very low Met target will result in it also meeting its Lys, Thre, and Tryp targets (and then some, mostly expressed as waste - LOTS of waste), but doesn't tell us anything about any of its other needs - Calcium, Phospherous, a host of trace metals, minerals, vitamins...

 

[U_Stormcrow]

Gotcha. So it sounds like methionine is the aa most likely to be deficient in a diet with a lot of grass.
This may be why mine stuff themselves with grass and then come and top up with leftover cat food!

EXACTLY. Met is the hardest AA to find in good quantity in green growing things.

Protein building begins with Met (in almost every case). Literally the first amino acid used to build a protein is Methionine. Now Met is often cleaved off later in the process - its why the needs for Lys and Thre are higher than Met - but without Met to start with, none of the others can be used. Its like the train engine moving box cars around to build a bigger train....