I think some people care because they do not like the idea of possibly feeding chicken back to chicken. Some people are also vegetarians and extend that to their animals. Others believe that the birds don't eat meat and that all veggies is natural for them. Various views on the topic.
However, I buy feed with animal protein as I feel it is more complete for omnivores.
I believe it all started with the mad cow disease scares, but feeds that have animal protein in them today usually say "No ruminants". No mad chicken disease so far, that I know of, LOL. And the mad cow would disappear if they'd quit grinding up dead cows and feeding them back to cows for cheap food.
My feeds contain porcine protein and I buy them because they are NOT vegetarian. With the trend toward vegetarian feeds, I believe we acquired many problems like unsatisfactory feathering, feather picking, etc, in our birds. Chickens are omnivores, not vegetarian by nature. And just because someone feels a certain food regimen is good for them as humans, does not mean it is necessarily good for an animal or bird. There are fine feeds of both types on the market and I've used both, but I make it a point to use the ones that still contain animal protein most of the time. JMO, for whatever it's worth.
I give feed with no animal protien because I don't like the idea of the hens eating other hens that is just weird and I am afraid of disease transffering through feed. I feed purina Layena sunfresh but I also five meat scraps occasionally and they catch mice and bugs.
I feed no animal protein "feed" but do give my girls various treats that include them. Scambled & boiled eggs, Spagetti sauce(with hamb & sausage), chicken and turkey carcasses after I have cook them down for stock. It's all organic. They eat anything I do
I purchase vegetarian feed for my hens. It's really the only gurantee you can provide to yourself or a customer that chickens will not be fed chicken. I am just against the principal of feeding animals to themselves, not that I misunderstand that chickens are omnivores.
When you investigate the industry of rendering, which provide bulk animal 'meals' for protein, some vary sketchy things go on. The concept of using high pressured water and air cannons to ensure "100% carcass utilization" is the norm. There is just some scary implications to human and animal health... I recall recently the group of workers who have come down with a brain disease after blowing pork brain matter out of skulls for extended periods of time.
Then let's no mention household dogs and cats making their way into the protein chain. No thanks. Not for me.
After starter feed, I do just as Henry does with choice of brands and occasional meat (cooked) from the kitchen.
When you look at protein sources in some feeds, a lot of choices are made for us which we would never even consider. I understand not wasting some of these products but, heck, I use a lot of organic garden fertilizer. I'd rather feed these byproducts to the worms in the ground rather than my egg layers!!
This idea of chickens as omnivores is fine with me. But, if you really want to be offended, take a look at what is often fed to our beef and milk cows. Even tho' ruminants as a feed component was given up (I'm sure with some reluctance) a few years ago. It's just wrong (& extremely distasteful ) to give some of this stuff to Daisy the Milk Cow.
I buy the average layer feed for my chickens which around here contains no animal by-products. So I guess you can say it is vegetarian style feed. Not my choice but it is what is available. My chickens also are given meat to eat. They get all of my kitchen scraps and those include meat pieces. I buy crickets and meal worms for them. When it rains heavy here the ground releases mass quantities of earthworms and the chickens have a stellar day with those. My husband hunts or we are given game meats which I often cook portions and feed to our animals - including the chickens. I aslo do not waste the broth from those meats and usually cook a cheaper variety of rice in it and feed that to the chickens so they get the nutrients in the broth as well.
I have done alot of reading and researching and it is my understanding that unless the chickens get meat protein they cannot recieve a complete long chain fatty acid from the non-animal protein feeds. (Human cannot either even with complex diets). This is crusial to their development. I believe it is why we see poor feather, generally thinner birds and problems with picking, feather eating and chickens that peck other chickens until they are literally eating one another alive.
With all of this said, when I cook chicken and have scraps after cooking I do feed it to my chickens in whatever mix of kitchen scraps I have. I don't set out to feed chickens chicken but if there are scraps in the bucket they do get it. I also feed them back their own eggs. I get up to 32 eggs a day now. When they start stacking up I cook them and feed them to my layers and my chicks. It is a renewable source of protein (and calcium when I crush in the shells) for them.
If I could find a packaged feed that included some good, organic, grass-fed animal protein, I would feed it.
However, the only organic feed available here is vegetarian, so that's what we start with. We also supplement with all the meat table scraps (organic) including bones from pork chops and stuff like that that they love to pick over. Plus occasional canned tuna and organic organ meats from the grass-fed animals we buy from local farmers. And eggs.
Personally, I would rather have some of their protein come from animal sources rather than predominantly soy (which I don't like for many reasons including environmental ones). I have a feeling that some important micronutrients are lost when using all plant protein. I know they try to add them back in as supplements into the feed, but I very heartily believe that the food scientists are playing a guessing game when it comes to micronutrients, and that WHOLE foods are always best. Since chickens are omnivores, I beleive they're better off eating an omnivorous diet to be truly healthy.
Yesterday was our first warm spring-y day. I took the girls out onto my little raised veggie garden bed and let them scratch around in the hay mulch and soil. They were in HEAVEN finding worms and grubs; it really made my heart glad!