When are hens fully grown?

[clickchicks]

For discussion: what is the average age that a hen stops growing and is considered "filled out" weight-wise?

I have my 3 hens. A Barred Rock, a Sapphire Gem, and an Australorp, all are right at or just under 6 months old.

Originally I had a 2nd Australorp who passed away, she was emaciated at necropsy so I've been checking everyone's weight every few weeks just to make sure. So far, everyone has gained at each weight in.

The BR is just over 3 1/2 lbs, the Australorp is at 4 1/4 lbs and the Gem is around 3 1/4lbs.

All of them were originally from hatcheries, which as I understand it means they are usually smaller. But when do they reach their full weight? Aside from the Gem, which are supposed to be a little smaller, these girls seem shrimpy compared to the 6-7 lbs Dr. Google says they should be.

They have 24/7 access to food, this is what they eat: https://muenstermilling.com/store/products/chicken-food/milestone-starter-grower-chicken-food/

Its a starter/grower but I plan to switch to their brand of layer once this bag is done. They have free access to oyster shell, though on that note none of them have shown signs of being ready to lay, other than combs/wattles turning red. No squatting, don't really seem to eat the ES, no one is interested in the nesting boxes.

Pictures:

They are all very active and love to forage. They don't free range, but do have a fairly large area they get to enjoy during the day (about 30ft x 20ft). Sometimes I give them a handful of sunflower seeds or some fruit as a treat, but mostly they just forage and eat their chicken food.

 

[FuzzyCritters]

My smaller breeds were pretty much completely grown at 7-8 months. For larger breeds, it can be a whole year until they are full grown.

 

[EggSighted4Life]

these girls seem shrimpy compared to the 6-7 lbs Dr. Google says they should be.

Hi there, and thank you for caring enough about your flock to make this kind of effort!

I'm sorry for the loss you experienced..

Juvenile birds including the one you lost can seem so bony and awkward.. I would say unless necropsied professionally and stated to be emaciated I would hesitate to truly think that.. but with follow up suggestions and questions, etc.

The ladies you are asking and talking about right now quite simply are pullets and not hens at all.. They earn their technical badges of hen or cock/rooster at one year old.. though this is not IMO when they are fully grown or mature.. and they will go through several stages along the way! Under one year old is when you look at the cockerel and pullet weights on their standards.. And I wonder.. are these the minimums, maximums, or average weights stated in the SOP??? I should know this!

I would quit obsessing about weight and get a fecal float to check for internal parasite load.. unless you checked the intestines on the one that passed and saw nothing.. If she was truly emaciated she may have had crop, gizzard issues (maybe she swallowed something others didn't), Marek's, or other unknown genetic condition. If you lose another.. send it to your state poultry lab for necropsy..
State poultry labs

Otherwise your ladies look lovely! If you can find another.. grower/flock raiser.. in your price range with ingredients you like and readily available.. I would personally stick with between 18-20% protein (like you currently have with OS on the side) for these dual purpose ladies that are a little heavier bodied than the higher production Leghorn (in theory). I've raised literally hundreds of chickens.. no two grow exactly the same rate.. and you've already touched on the whole hatchery variability... According to my research.. your using only 18% protein *might* reduce muscle building and if folks are trying to increase growth rate are told to increase protein.. to reduce growth rate reduce protein always.. Many chick starter feeds are 22% protein and what I would consider the norm.. I personally use 20% flock raiser (i'm not able to go organic at this point) with OS on the side from start to finish for all my birds with good (maybe not maximum chick wise but still very good) results

HOWever.. I know they are adding in the amino acids needed to the lower protein (and vegetarian) formulas and also that the calories will STILL be consumed equally to maintain their weight and meet their energy need.. more active (and or heftier) birds eat more feed because they spend more energy.. and the muscles of active birds are longer and lankier instead of those who have sat around with no stretching or use thereof. I also know that carbohydrates including fiber are an important source of energy AND have an equal amount of calories as protein.. so I'm not exactly sure.. why going (or if) going higher protein will truly promote more growth or not.. UNLESS.. even though the weight of carb and protein 1g = 4 calories.. MAYBE they don't have the same VOLUME.. This is definitely something that get's factored into feed.. All animals also have a volume limit.. though I'm not 100% sure how.. Sorry you asked, I uhm... think too much!

Chickens don't eat in the dark.. but rats, raccoon, and many other things do. Almost NONE of my birds meat the stated weights claimed, or lay rate for that matter, or even onset of lay age!

The larger the stated breed, the slower the growth rate in my experience.. Orpington or Faverolle will finish filling out much later than Leghorn for example. I'm gonna go long and say it can take up to 2 years to reach their full filled in state.. Think about human terms, relatively. Youngsters have some baby fat, teenagers are lanky and awkward, 20's filling in. 30's topped out and filled in/prime, 40's maintaining or declining in muscle to fat ratio.

Also, it's great that you have a baseline weight on your birds.. I will still do it on occasion just not too often.. when birds go into molt they can lose a good amount of weight as even their reproductive system shrinks back in size internally during that time.

Hope this help some!

 

[Sally PB]

Very informative. Thank you!

 

[clickchicks]

@EggSighted4Life
Thank you so much for all of this info!

The pullet that died was necropsied by a state lab, they noted she was in poor body condition (she was 1.5 lbs at 4 months old) and had muscle atrophy. The cause of death was an infection that then caused multiple organ failure, though I didn't know at the time to get additional testing to figure out what the infection was. Fecal was done on other birds at the time and thankfully came back negative.

I'm glad to know that there's still a lot of filling out being done the first year. They are bug catching machines which I hope is contributing something positive to their protein intake, but I wonder if keeping them at around 18% will just encourage slow, even growth for longer... and if that's even a bad thing in a bird that will never be eaten. I see why fast weight gain is desirable for meat birds, but as long as I know its actually healthy for them to do so, maybe its ok for them to be taking it slow?

Being hatchery birds I guess I'll never know what they "should" weigh anyway... maybe the breeding birds were only 5lbs and these guys are closer than I think

I overthink things too, and I'm a worrier. Its important to me that everyone is happy and healthy

 

[centrarchid]

My American Dominiques and American Game hens are a solid year old before mature weight is realized, even though they might be in lay by 8 months of age.

 

[neo71665]

laying eggs

 

[Mrs. K]

If you birds are active with good feathers, and bright eyes and laying, they are pretty much in optimum health. They look very good in the pictures.

 

[Pghelp]

Pretty girls! I'll bet your Sapphire Gem and the Barred Rock will be laying soon. Mine were just under 6 months when they started to lay. I wouldn't worry about the weight on these girls. They look healthy and bright eyed. In the searches you get a range of weights but mine (hatchery also) never reached what they claim. My Sapphire Gem who is 24 weeks tomorrow began laying a couple of weeks ago. Be prepared for them to become voracious dinosaurs when they start laying! Mine couldn't stuff themselves enough when they started to lay. I feed a layer feed, they free range, and we supplement with greens gleaned from our local Chinese restaurant and farmers market. Occasional treats of sunflower seeds or mealworms, and always oyster shell available. Oh, I'd say my 24 week Sapphire Gem is about 2 1/2 pounds and she's healthy and active. I expect she'll fill out more as she reaches one year. That's a shame about the one you lost but it looks like you're doing great with these!