The fleece hides the problem in a Merino
A young Merino failing to thrive is easier to miss than almost any other lamb, because the breed's dense fleece keeps growing even when the body underneath is not. A lamb can look round and well covered while its ribs are sharpening and its growth has stalled. That is why the first sign in a Merino is usually found by hand and by scale, not by eye: weight gains flatten across several days, and a hands-on condition check finds the spine and ribs increasingly prominent under the wool, with the lamb feeling light for its apparent size when you lift it.
Behaviour that gives a struggling Merino away
Behaviour cuts through the wool's disguise. A thriving young Merino nurses hard, follows its mother closely, and joins the lamb races and play that fill a paddock in the evening. A Merino failing to thrive lags behind the ewe, stands apart with its head down and ears drooping, and lies down for longer stretches while its mates explore. It may bleat often but nurse weakly, giving up at the udder quickly. Twin Merinos deserve special suspicion: the smaller twin can be steadily outcompeted while still looking acceptable under a full fleece, and only the weigh scale reveals how far behind it has fallen.
Gut and skin signs specific to young Merinos
Check a struggling Merino lamb's rear end closely, because scours paste into the crutch wool and can go unnoticed from a distance while the lamb dehydrates. Part the fleece over the back and belly: the skin should be pink and clean, and bare or scabby patches, lice irritation, or a harsh, dull, easily pulled fleece all suggest a lamb under nutritional or parasitic pressure. Once the lamb is grazing, worms are a leading cause of poor growth in Merinos, showing as a pot belly with a thin back, pale eyelids, and sometimes a soft swelling under the jaw. A harsh, shedding birth coat that fails to develop into dense crimped wool also points to a lamb that has been underfed or unwell during its early growth.
Why young Merinos fall behind
The causes mirror the breed's sensitivities. Merino ewes often milk more modestly than meat-breed ewes, so a lamb on a first-time or under-conditioned mother may simply be underfed. Fine, small lambs chill easily in their first days and a cold start can echo for weeks as poorer growth. Bottle-fed Merino lambs fall behind on feeds mixed too dilute or given too far apart. Internal parasites build quickly on lambing paddocks used year after year, and a lamb weaned onto contaminated pasture can stall within weeks. Sorting out which pattern fits, feed intake, gut signs, or a cold start, directs whether the remedy is supplementary feeding, a pasture move, or veterinary treatment.
Acting early, with evidence for the vet
Bring a vet in when a young Merino is losing weight, scouring persistently, pale around the eyes, or dull and off its feeds, because small fine-boned lambs have little reserve. Arrive with the lamb's actual weight history, not a guess: birth weight, weekly weights, and when the stall began are exactly the evidence that separates a feeding problem from a disease problem. Storing that growth record in KinsLe in each lamb's Pet Passport keeps the curve visible week to week, so a flattening trend triggers action while the lamb is still easy to turn around.