How Long Do Sheep Live? Sheep Lifespan and What Limits It

Author: Elliott Garber, DVM

A healthy, well managed sheep lives about 10 to 12 years. That is the figure from Sheep 101, the educational site written by Susan Schoenian, sheep and goat specialist at the University of Maryland’s Western Maryland Research and Education Center, and it is the honest headline answer. Most commercial ewes never get there. They leave the flock years earlier, and the reason is usually sitting in the ewe’s mouth.

That gap between how long a sheep can live and how long a sheep usually lives is the whole subject. Biological lifespan is set by teeth, joints, and luck. Productive life is set by lambing records, udder soundness, condition, and the arithmetic of replacing an older ewe with a younger one. They are different questions with different answers, and a page that gives you one number is answering only one of them.

If you keep sheep, the number that matters is the one you can influence, so start by writing things down. A free sheep profile on Creatures holds a birth or purchase date, lambing history, treatments with their withdrawal dates, and a running body condition record, which is how you tell an eight year old ewe who is thriving from a five year old quietly going backwards. The Creatures sheep hub covers breeds, care, and management alongside this guide.

How long do sheep live?

Ten to twelve years is the working answer for a sheep that is fed properly, kept sound, and not culled for production reasons. Schoenian’s comparison is a useful one: sheep sit in roughly the same band as a large breed dog, and some breeds, Merino among them, are known for running longer.

Sheep 101 also states that it is possible for a ewe to stay productive past 10 years of age if she is well fed and managed and stays healthy and sound. That is the ceiling, not the average, and the gap between them is not mysterious. It is teeth, feet, worms, and lambing. We have left out the “oldest sheep ever” record that usually travels with these numbers, because we could not verify it at the record keeper’s own page while writing this, and an unverified superlative is not worth the ink.

The teeth are the clock

This is the most concrete thing on this page, and it is the part most owners have never been shown.

Sheep have no upper incisors. New Mexico State University Extension’s guide to aging sheep by dentition puts it plainly: ruminants lack upper incisors and instead have a dental pad, and small ruminants have three pairs of lower incisors plus one pair of canines sitting in the corner position and counted as a fourth incisor pair. That lower row of eight clips the grass. Behind them sit six pairs each of upper and lower molars, which SDSU Extension’s guide to mouthing sheep counts as 24 grinders.

The eruption schedule is why the mouth doubles as a birth certificate. Lambs carry temporary milk teeth. From about 12 to 18 months the first pair of permanent incisors comes in, and a further pair erupts each year until the sheep is four, working outward from the center. A sheep with the full set of permanent incisors, unworn and unbroken, is a “solid mouth” sheep. After that, as NMSU notes, exact age gets hard to call and you are reading wear instead.

Then the wear starts, and it is not gentle. Sheep are low grazers: a 2025 study of incisor disorders in Merino sheep in the Journal of Veterinary Dentistry describes them as preferring to graze at ground level and continuing even when plants are short and close to the soil, which is exactly what makes them vulnerable. SDSU adds the mechanism, that grazing animals ingest abrasive particles along with the forage and shorten and damage teeth over time, and NMSU is more specific still, noting that structural loss of incisors happens more readily on sandy soils where sheep pick up grit with every bite.

Eventually the teeth go. A ewe with broken, short, or missing incisors is called “broken mouthed,” and SDSU puts the typical onset past five years of age. The consequence is not cosmetic. That same Merino dentistry study summarizes the literature as showing sheep with incisor loss taking in nearly half as much per bite as sheep with sound incisors. A broken mouth ewe standing in knee deep grass is still, functionally, on short rations.

The effect on the animal is now measured. A 2025 study in Animal Welfare scored incisor wear against body condition in 818 extensively grazed Dohne Merino ewes aged 2 to 10. Wear affecting more than a third of the enamel was present in at least one incisor in 99 percent of ewes over five years old, and greater wear was significantly associated with lower bodyweight and lower body condition score in ewes over two, independent of age. The authors call it a preliminary study of one breed in one system, so read the 99 percent as a description of that flock rather than a universal rate. The direction is what carries: worn incisors and poor condition travel together.

Molars matter too, and nobody checks them. SDSU points out that if the grinders are worn or damaged the animal cannot break feed down small enough for the rumen microbes to work on it, and that in severe cases broken mouthed animals lose condition rapidly and can starve. A thin ewe on good pasture is a mouth problem until proven otherwise.

The response is unglamorous and effective. Mouth every ewe you buy, mouth the flock when you make culling decisions, and check the mouth of any thin ewe before you reach for a dewormer. A broken mouth ewe is not automatically finished either: SDSU notes these sheep need feedstuffs with a smaller particle size that are easier to chew, which is a management decision rather than a death sentence, provided she is not competing at a feeder with a full mouthed flock.

Productive life is not the same as lifespan

Most ewes leave a flock long before biology would take them, and this is normal husbandry rather than neglect.

Sheep 101 puts peak productivity between 3 and 6 years of age, with decline beginning after 7, and notes that ewes are removed before they reach their natural life expectancy partly to make room for genetically superior younger animals. Ohio State University Extension’s cull ewe checklist reports that age is the leading reason for culling sheep in the United States, citing the USDA APHIS sheep study, and puts the average culling age in western flocks at 5 to 6 years.

Numbers from elsewhere land lower. A 2019 study in PLoS One on New Zealand dual purpose ewes reports that average longevity under commercial conditions is 4.3 to 5.0 years, with annual within flock loss of 4.6 to 4.9 percent. We are not going to average those into one tidy figure. American western range flocks and New Zealand dual purpose flocks differ in feed, climate, and culling policy, and the spread between roughly 4 and 6 years is itself the useful information.

Culling is rarely about age alone. OSU’s checklist runs through the rest: loss of teeth, udder health and structure including mastitis and poor teat placement, production history, lameness from foot scald or foot rot, disease and internal parasite status, and a history of prolapse. Ohio State also notes that in eastern systems with more feed available and smaller pastures, ewes may stay productive longer than the western average suggests. Cattle run on the same two clocks, and our cattle lifespan guide puts the dairy and beef cull rates side by side to show how far apart they are.

What actually shortens a sheep’s life

Internal parasites

The barber pole worm is the one that kills. The Merck Veterinary Manual’s professional page on gastrointestinal parasites of small ruminants, fully reviewed in June 2023, calls Haemonchus contortus the most common pathogenic gut parasite in small ruminants and notes it is prevalent in tropical and subtropical regions and in regions with summer rainfall. Heavy infections produce profound anemia, ill thrift, and high mortality, and in the hyperacute form death can occur within a week of heavy infection without notable clinical signs. Merck also flags the trap: diarrhea is not a characteristic sign of pure Haemonchus infection, so waiting for scours means missing it.

The modern control approach treats individuals rather than calendars. The American Consortium for Small Ruminant Parasite Control describes FAMACHA as a diagnostic card that matches lower eyelid color to anemia levels as an indicator of clinical barber pole worm infection, used as part of targeted selective treatment, and is explicit that producers must be trained before they can get a card. Our sheep deworming guide covers scoring, fecal egg counts, and refugia in depth.

Feet

Lameness is a slow lifespan problem because a sheep that will not walk will not eat. Merck’s page on contagious footrot in sheep, fully reviewed in June 2022, describes virulent footrot as extremely contagious, with morbidity approaching 100 percent under suitable conditions, and records that affected sheep do not compete well for food, lose body condition, and produce less wool. Merck’s own control advice includes culling animals that do not respond to treatment, which is a lifespan consequence stated plainly. Regular attention to feet is the cheapest prevention there is, and our hoof trimming guide walks through it.

Copper, which has the narrowest margin of any common livestock mineral

This one deserves its own paragraph because it kills healthy adult sheep with no warning. Merck’s copper toxicosis page, fully reviewed in April 2026, states that sheep are the most susceptible species. The mechanism is what makes it dangerous: copper accumulates quietly in the liver until storage capacity is exceeded, and then a stressor such as transport, handling, bad weather, pregnancy, lactation, hard exercise, or a nutritional setback can trigger a massive release and a hemolytic crisis. Merck notes that treatment is often unrewarding, so prevention is the whole game.

Merck’s nutritional requirements of sheep, fully reviewed in September 2025, gives the shape of the margin. Pregnant ewes need roughly 5 mg of copper a day, the amount supplied when forage carries 5 ppm or more, and yet toxicity may be produced in lambs fed diets of 10 to 20 ppm, particularly when the copper to molybdenum ratio exceeds 10 to 1. Merck advises keeping that ratio between 5 to 1 and 10 to 1. Note that Merck’s toxicology page cautions against treating any published concentration as a fixed toxic dose, because disease can occur at lower concentrations when the rest of the diet favors retention. Feed a mineral formulated for sheep, and read our sheep minerals guide before you buy anything.

If you also keep goats, do not carry the goat rules across. Merck’s page on nutritional diseases of goats, fully reviewed in July 2025, states that goats have relatively high copper requirements compared with other species. Goats and sheep genuinely differ here, and the difference runs in opposite directions. Our goat lifespan guide covers the goat side, including the copper bolus trap that comes with using copper against barber pole worm.

Lambing

Late gestation and lambing are the riskiest stretch of a ewe’s year. Merck’s page on pregnancy toxemia in sheep and goats calls it the most common metabolic disorder of pregnant small ruminants and notes that it occurs more often in animals carrying multiple fetuses, that most cases develop 1 to 3 weeks before lambing, and that even with aggressive treatment and intensive nursing it is not unusual to see case fatality rates above 40 percent.

Prevention is body condition managed in advance. Merck advises that ewes should not enter the last 6 weeks of gestation below a body condition score of 2.5 out of 5, and points out that raising body condition by one point takes about six weeks, so the intervention has to happen at breeding or mid gestation rather than in the lambing shed. Both underconditioned ewes at 2 or below and overconditioned ewes at 4 or above carrying multiples are named as highest risk. Our lambing guide covers the rest of the season.

Predators and weather

Predation is real, but the share varies enormously by region and system, so be skeptical of anyone quoting a single national number. USDA NASS state releases show the range clearly. In Wyoming, predators accounted for 65.8 percent of all sheep and lamb deaths in 2025 and 4.6 percent of the sheep and lamb supply. In Utah the 2024 figure was 65.6 percent of deaths. In Idaho, by contrast, predators accounted for 31 percent of deaths in 2023 and nonpredator causes for 69 percent. Coyotes lead the predator column in all three. Idaho’s release names the largest identifiable nonpredator causes as weather conditions, lambing complications, and enterotoxaemia, which is a fair summary of what an ordinary flock actually loses animals to.

Pet sheep, fiber flocks, and wethers

Take production culling out of the equation and the biological range is what you get. A pet or fiber sheep that is kept sound has a realistic shot at the upper half of that 10 to 12 year band, because nobody is going to move her along for a light lamb crop. What changes is the risk list.

Wethers carry a specific danger. Merck’s page on urolithiasis in ruminants, fully reviewed in November 2025, calls obstructive urinary stones a substantial cause of illness and death in male ruminants, most common in wethers, bucks, and rams, with pet animals explicitly named among those at risk, and reports that early castrated males have the highest incidence of urethral obstruction. Merck’s prevention list is the pet owner’s checklist: delaying castration to at least 8 weeks improves urethral diameter in lambs, water intake should be encouraged with clean palatable water, and the diet should be high forage with grain and pelleted feeds limited, since high protein feeds contribute to stone formation. Signs to treat as an emergency include straining, stretching out, vocalizing, teeth grinding, and abdominal distension. A wether apparently straining to urinate needs a veterinarian the same day. If you have not lined one up, our guide to finding a large animal vet covers the small ruminant directory and the questions worth asking before the day you need an answer.

The other pet sheep failure modes are ordinary ones: grain fed to an animal with no job, skipping shearing on a wool breed, letting hooves grow, and assuming one sheep is fine alone. Sheep are flock animals, and the Creatures sheep hub covers companionship, shelter, and breed choice in more depth. Fleece needs the same attention whether an animal earns its keep or not, which is what our shearing guide is for.

The records that actually change the number

Everything above is a trend, not an event. A ewe does not become broken mouthed on a Tuesday, and a copper problem gives no early signs at all. What separates flocks that get long lives from flocks that get surprises is whether anyone wrote things down.

Keep these per animal: date of birth or purchase, individual identification, every lambing with its outcome, body condition scores across the year rather than only at weaning, mouth checks recorded by age, parasite treatments with the product and its withdrawal time, and hoof trims. A free Creatures animal profile carries all of it across 13 record types, including examination for vet visits, medication, test results, and physical measurement for weight and body condition over time, with medical record types private by default. You can set reminders for shearing, hoof trimming, and boosters on a due date dashboard and subscribe to them as a calendar feed, import a clinic PDF or lab report into an animal’s history after a visit, and download a printable record packet to take with you, which needs a free account.

This is how you notice that one ewe has dropped half a condition score across two consecutive checks, which is the moment a mouth check is worth doing and a treatable problem is still treatable. Our sheep weight guide covers measuring and tracking condition without a scale.

Creatures is the records, marketplace, and directory layer for keeping all of this in one place. It is not a veterinary referral service, and nothing here replaces your vet.

Sheep lifespan FAQ

How long do sheep live as pets?
The same 10 to 12 years, and more of them get there, because pet sheep are not culled for production. Wethers need particular attention to diet and urinary health, and every sheep needs company, hoof care, and, in wool breeds, shearing.

Why do most ewes leave a flock at 5 or 6?
Because productivity peaks between 3 and 6 and declines after 7, and because a younger replacement is usually genetically better. Ohio State University Extension reports age as the leading reason for culling sheep in the United States.

What is a broken mouth ewe?
A sheep with broken, short, or missing incisors, typically past five years old. She cannot clip forage efficiently, so she loses condition even on good grass. She can often still be productive on feed with a smaller particle size, fed where she is not competing with full mouthed ewes.

Can you tell a sheep’s age by its teeth?
Up to about four years, yes, and quite precisely. A pair of permanent incisors erupts each year from roughly 12 to 18 months until the full set is in at four. After that you are reading wear and gapping, and the estimate gets softer.

Do sheep need copper supplements?
Not on a hunch. Sheep are the most susceptible species to copper toxicosis, the accumulation is silent, and treatment after the fact is often unrewarding. Feed a mineral labeled for sheep, and let your veterinarian decide about supplementation on the basis of testing.

Do hair sheep live longer than wool sheep?
No published head to head longevity comparison supports that, so we are not going to claim it. What is fair to say is that hair sheep are not exposed to shearing and fleece related problems, and that breed does matter to some of the limiters on this page: Merck records that the potential for genetic selection for increased resistance to footrot has been established, with certain breeds appearing more resistant to infection.

Do this next on Creatures

If you keep sheep. Start a free profile and record the birth or purchase date, tag number, and lambing history: add your sheep (no account needed to start). Then log body condition scores, mouth checks, treatments, and hoof trims with add a record, which opens for visitors and needs a free account to save. Help center: adding an animal, adding a record, and health and medical records.

If you are looking for sheep. Browse the sheep marketplace, and mouth every ewe you consider before you agree a price. To hear when the right animals appear near you, set a sheep listing alert. See saving searches and using your watchlist for how alerts work. Our sheep cost guide covers what older and younger ewes actually go for.

If you breed or sell sheep. Get listed where buyers are already searching in the breeder and farm directory, which lists trusted breeders and farms by species and state, and create your organization profile to publish your flock, records, and available lambs under one name. See getting listed in the breeder directory.