Entropion in Sheep: In-Turned Eyelids in Lambs and Adult Sheep

Entropion is a condition where the eyelid rolls inward instead of resting normally against the eye. In sheep, it usually affects the lower eyelid and is most often seen in lambs shortly after birth. When the lid turns in, the wool, eyelashes, and skin rub directly on the cornea. That constant friction is painful and can quickly damage the eye.

Many cases in lambs are considered congenital or inherited, which is why flock records matter. Merck Veterinary Manual notes that entropion is a frequent inherited eyelid defect in ovine breeds, while Cornell's sheep flock protocol describes it as a hereditary problem that should be recorded and considered in breeding decisions. In lambs and foals, Merck also notes that some cases are secondary to enophthalmos associated with mild dehydration and/or corneal ulceration.

The good news is that early cases often respond well to prompt care. If the eyelid is corrected before the cornea is badly irritated, many lambs recover with normal comfort and vision. Delayed treatment raises the risk of ulcers, scarring, and long-term eye damage, so this is a condition worth addressing early with your vet.

In lambs, entropion is commonly linked to inherited eyelid conformation. That hereditary tendency is important at the flock level because affected lambs may be more likely to come from lines that pass the problem on. Cornell specifically advises recording cases in the lambing book and not keeping affected lambs for breeding.

Not every case is purely genetic, though. Merck Veterinary Manual explains that entropion can also occur secondary to pain-related eyelid spasm, scarring, or enophthalmos. In lambs, mild dehydration can make the eye sit deeper in the socket, which can encourage the lid to roll inward. Corneal irritation can then trigger more spasm, creating a painful cycle.

In adult sheep, an in-turned lid is less common as a primary inherited problem and may raise concern for weight loss, dehydration, chronic eye pain, or scarring that changes eyelid position. If an older sheep develops entropion, your vet may want to look beyond the eyelid itself and assess the animal's overall condition.

Diagnosis is usually based on a hands-on eye exam. Your vet will look for the eyelid margin rolling inward, hairs contacting the cornea, tearing, blepharospasm, and any cloudiness or ulceration. In many lambs, the appearance is classic enough that diagnosis is straightforward during a farm visit.

The next step is deciding how much eye damage is already present. Your vet may examine the cornea closely and use fluorescein stain to check for an ulcer if the surface looks cloudy or painful. That matters because a lamb with a simple inward-rolled lid may need different follow-up than one with a corneal ulcer.

Your vet may also consider other causes of a sore eye, including pinkeye, trauma, foreign material, or eyelid injury. In older sheep, diagnosis often includes asking why the lid changed position in the first place, especially if the animal is thin, dehydrated, or has another eye problem contributing to pain.

Prevention starts with early observation. Cornell's sheep flock protocol recommends checking lambs before they leave the jug and watching closely for additional affected lambs so treatment can happen early. That practical step can make a major difference because mild cases are easier to correct before the cornea is injured.

Breeding decisions also matter. Because entropion in lambs is often hereditary, affected lambs should be clearly recorded, and many flock health programs advise against keeping them as breeding replacements. If several related lambs are affected, your vet and flock advisor may suggest reviewing sire and dam lines more broadly.

Good lambing management supports prevention of secondary cases as well. Prompt colostrum intake, hydration, and close monitoring of weak lambs may reduce the chance that enophthalmos from dehydration contributes to eyelid inversion. In adult sheep, prevention is less about genetics and more about addressing weight loss, dehydration, and painful eye disease early so the eyelid does not roll inward as a secondary problem.