Short answer: Skeletal problems in broilers are bone and tendon failures that usually show up in the last two weeks: legs bent inward or outward, birds that sit on their hocks, and a tendon slipping out of its groove at the hock. They come from fast growth outrunning the skeleton, a mineral and vitamin balance that is wrong in the feed, slippery floors and long bright light. Fix the floor and the feed balance first, and follow your vet's advice on any flock where the problem keeps rising.
Key takeaways
- Bent legs in the last two weeks are rarely one cause. Look at growth, feed and floor together.
- A slipped tendon shows as a bird hopping or walking on the hock. It is a balance and growth issue more than an injury.
- Test the walk once a week with the same route, so a rising count means something.
- Do not add bone meal, limestone or premix by feel. Weigh them against the supplier's spec.
- Cull a hen that has lost the ability to reach feed and water rather than let her waste in a corner.
Bent legs at week five are rarely one thing
A farmer rings us with a photo of a pen where a handful of birds are walking on their hocks, legs turned out like a duck. He asks which feed he should change. The honest answer is that a single feed change rarely fixes it. Bent legs are the end of a chain. The links are growth speed, minerals and vitamins, the floor under the bird and the light she lives under.
The good news is that each link can be checked. You do not need a laboratory to see that the chain is failing. You need to know what each problem looks like, what it usually comes from and what you can change this week.
The problems, one by one
Broiler skeletal trouble covers several conditions that look alike from the walkway. The table sets out the four we see most often, when they tend to appear and what usually sits behind them.
| Problem | When you see it | What it looks like | Common contributors |
|---|---|---|---|
| Valgus and varus (bent legs) | Weeks 3 to 6, worse in fast flocks | Legs bowed out or in, birds walking on the hock | Fast growth, uneven feed, slippery floors |
| Slipped tendon | Weeks 4 to 7, often in the heaviest birds | One or both hocks sit out of place, bird hops or cannot stand | Mineral and vitamin balance, fast growth, weight |
| Tibial dyschondroplasia (TD) | Usually from week 3, found in the leg bone | Lameness, reluctance to walk, sometimes swollen hock | Calcium and phosphorus balance, vitamin D, fast growth |
| Rickets-type weakness | Younger birds, from the first weeks | Soft, bending bones, wobbly walk | Vitamin D and calcium or phosphorus imbalance |
These are not the same disease, and the vet will want to see a bird or two on the table before saying which one is in the house. That is why a post-mortem of a lame bird is worth the trip.
Bent legs: the bowed and the turned-in
Valgus and varus are the terms for legs that bow outward and inward. You see them most in birds that are growing fastest, because the bone and the joint at the hock cannot take the weight the muscles are putting on them. The leg is not broken. It is soft, and the bird is standing on a skeleton that has not caught up with the body.
In practice, a bird with bent legs walks with a wide stance or on the outside of the foot. She may still eat for a while, but she falls behind at the feeder and gets pushed out at the drinkers. The problem often starts in a few birds and spreads through the pen over ten days. If you catch it at the first bird, the rest of the flock may be saved by changing the floor and the feed.
Slipped tendon: the hop and the sit
A slipped tendon, often called perosis, happens when the tendon that runs down the back of the hock slides out of its groove. The bird hops on one leg or sits on the hock with the leg pushed out to the side. You will notice it in the heaviest birds, usually in the last two weeks, and they may be found sitting in the corner while the rest of the pen moves about.
The reason is in the structure of the hock, and the trigger is usually a mix of rapid growth and a mineral and vitamin balance that does not support the tendon and cartilage. Manganese and choline are two nutrients the literature links to it, but you cannot fix it with a single supplement added by guesswork. A correct premix in the right proportion, fed through the phases, is the approach your vet and your supplier should agree on.
Tibial dyschondroplasia: the growth plate that does not finish
TD is a failure of the growth plate in the long bone of the leg. Normally the cartilage at the top of the bone turns into bone as the bird grows. In TD that conversion stops, and the cartilage stays thick and soft, so the bone cannot carry the load. The bird limps, or stops walking, and a post-mortem will show the thickened plate.
It is linked to fast growth and to an imbalance of calcium, phosphorus and vitamin D, which control how the bone is laid down. A well-balanced feed that matches the phase does a lot to prevent it. A home mix that is short of premix, or a calcium source that varies from bag to bag, can produce it. Follow your vet's advice on the feed changes, and do not start adding calcium on your own, because too much is as harmful as too little.
Feed balance and the home-mix trap
The feed is the lever you can pull most directly, and it is also where the most damage gets done by well-meaning farmers. A home mix made from maize, soya and a bag of premix bought cheaply can look sound and still be short. The premix is the part that carries the vitamins and minerals, and a short measure of it means the bone and tendon simply lack the building material.
Use the premix in the proportion the supplier gives, and weigh it on a clean scale. Keep the calcium source, usually limestone or shell, in the ratio on the spec rather than in a scoop. Do not mix two premixes for the same phase. If you buy ready feed, write the phase and the date on each bag, and ask the supplier to confirm the mineral spec in writing. The home mixing guide is the place to start on the weighing, and the formulation basics show how one small error multiplies across a batch. If the birds are packed tight, the stocking density notes are the next thing to read.
Floors, litter and the bird that slips
A bird that cannot grip the floor puts her legs out to the side to stop herself sliding, and that sideways load bends the leg bones over time. Slats, smooth cement and a thin layer of litter over a hard floor are the usual suspects. A pen that is well littered and dry gives the bird something to push against, and it protects the joints from the constant knock of walking on hard surfaces.
Check the litter depth in the corners and near the feeders, where birds stand and turn. Keep mats or fresh shavings under the drinkers, and avoid a sudden build-up of wet litter by the door. The litter management notes cover the depth and dryness we aim for on a broiler floor. Good litter is not a luxury in a skeletal problem. It is one of the few cheap tools that works at once.
Light and the speed of growth
Light affects how much a bird eats and how often she eats it. Long periods of bright light make birds feed almost constantly, and a fast-growing bird on a constant feed supply puts on weight faster than her bones can keep up. Many farms reduce the problem by giving the birds a managed dark period, so they rest and the growth follows a steadier curve.
Keep the light programme steady from day to day, and change it in steps rather than all at once. The heavy broiler guide is worth reading alongside this one. Ask your supplier what programme suits the strain you bought, and check that the house is actually running it. A light that stays on at full power through the night is a common reason a flock grows faster than the chart and then shows leg problems in week five.
Need chicks for your next batch?
Send breed, number and town. We reply with price, hatch date and delivery cost in writing.
Keeping the growth on the chart
Growth speed is the single biggest lever in this list, and it is the easiest one to check. Weigh a sample of birds every week, at the same time of day, and compare the average with the chart your supplier gives for the strain. Weigh enough birds to be representative, and do not weigh only the biggest ones at the feeder.
If the flock runs well ahead of the chart in weeks two and three, the answer is usually to hold the feed to the chart rather than pile more on. Keep the uniformity in mind too. A flock with a wide spread of weights has a few birds carrying extra load and many that are falling behind. Spreading the feeders and filling them in small amounts several times a day evens the pen out, and that helps the legs and the sale weight at the same time. Our weight chart by week is the reference we use when we talk to farmers about this, and the Ross 308 guide covers that strain in more detail.
Worked example: a bent-leg cull
Start with the chicks. Ross 308 day-old chicks at GH₵20 each, 1,000 of them, is GH₵20,000 before a single bag of feed. Our price list has the current figures. Now suppose that by week six, 4 per cent of those birds are culled for bent legs or slipped tendon. That is 40 birds, and they were not going to be the lightest in the house. They were the heavy birds that could not keep walking.
If each of those 40 would have reached 2.5 kg, that is 100 kg of meat. Divide our live-bird price by the weight and you get about GH₵44 a kilogram, so the lost value is roughly GH₵4,400. That is before the feed the culled birds ate, which is the part that hides the loss. Now picture the same flock with the floor fixed, the feed weighed properly and the light stepped. If the cull falls to 1 per cent, you keep 30 birds and about GH₵3,300 of value.
The numbers make the case for weighing the feed and checking the floor. Both cost very little once the habit is in place.
A weekly walk test and feed check
- Pick a set route down the house and use the same one each week.
- Walk 20 birds slowly along it and count the ones that hop, sit before the end or swing a leg.
- Record the count and the pen or area so the number can be compared with last week.
- Take a weight sample and set the average against the strain's chart.
- Check the feed bag labels and the phase against the date on the house record.
- Confirm the premix is weighed at the spec rate and the calcium source is measured, not scooped.
- Check the litter depth and dryness in the corners and by the feeders.
- Note any changes made in the week, so you can tell which one made the difference.
When to ask the vet for a post-mortem
Ask your vet for a post-mortem when the lame count is rising, when birds are found with bent or swollen hocks, or when the flock shows several of the problems in the table at once. The vet will look at the leg bones, the growth plates and the tendons, and will compare them with the feed and the growth figures you bring.
Bring a fresh bird rather than one that has lain in the sun, and bring the feed bag, the phase, the growth records and the light programme. Follow your vet's advice on whether to change the feed, adjust the light or add a specific supplement. Culling a bird that cannot reach feed and water is the humane choice, and our questions page is a starting point for the practical side, and the vet can show you how to do it cleanly. Do not let a bird that cannot stand keep losing condition in the corner while the rest of the flock grows around her.
If you are starting a new house and want to talk through the strain and the growth plan, call us on +233 24 915 1503. Each broiler batch we sell comes with its batch record, and the broiler chicks page has the details.
Questions farmers ask
Are bent legs genetic?
Partly. The fast-growing strains are more prone to leg trouble because they put on weight quickly. Management and nutrition decide how much of that risk shows up. Check the growth curve for the strain you buy against your own feed and floor, and treat the strain as the starting point, not the whole answer.
Can I fix a bird that is already bent?
Usually not. Once the bone has bent, the bird is unlikely to straighten, although the feed and floor can stop the next lot from going the same way. A bird that can still reach feed and water can stay in the flock while you improve the house. A bird that cannot reach them needs culling, and your vet can show you how to do it cleanly.
What is the difference between bent legs and rickets?
Rickets is a weakness of the bone from too little vitamin D, calcium or phosphorus, and it shows most in young birds with soft, bending bones. Bent legs in broilers are usually a result of fast growth and an imbalance in the feed, and they show more in the last weeks. Both come back to the feed balance and the growth rate, so both need your vet's view.
How much calcium should I give my broilers?
The right level depends on the phase, the strain and the other minerals in the feed, so there is no single figure to copy from a neighbour. Use the level on your feed spec or your supplier's phase sheet, weigh it, and do not add limestone or bone meal by feel. Too much calcium is as harmful as too little, so check with your vet if you are unsure.
Does light affect skeletal problems?
Yes, through growth speed. Long periods of bright light keep birds eating and growing fast, which puts more load on bones and tendons than the skeleton can carry. A managed dark period gives the bird rest and a steadier growth curve. Change the light in steps and talk to your supplier before you make a big change.
Are the chicks I buy from you more likely to have these problems?
Leg problems in broilers develop mostly on the farm, in the later weeks, because of growth, feed, floor and light. Good chicks help the flock, but the house does most of the work. Our batch record shows the vaccines each hatch received and when, so you have a clear starting point when the flock is older.
Should I cull a bird with a slipped tendon?
If the bird cannot reach feed and water after a day or two, or she is losing weight fast, cull her humanely. A bird that can still reach both can stay while you check the feed and the floor. Your vet can show you the method and the disposal, and the rest of the flock stays under the weekly walk test.
