How to weigh a sheep: complete guide for sheep farmers

What equipment to weigh a sheep?

A professional sheep weighing chain has three parts: a weighing crate (OviLamb Box or lamb scale), two load bars (Gallagher 600 mm recommended for sheep up to 150 kg) and a weigh head such as the W0 which stores up to 50,000 records with RFID identification.

For flocks under 100 ewes, a Kit 580 with W0 (~£1,500 inc VAT) is enough. Above that, a fixed scale with paired RFID reader pays for itself within one season.

• Sheep crate: OviLamb Box (lambs ≤ 50 kg) or lamb scale (up to 150 kg)
• Gallagher 600 mm load bars: ±100 g, IP67
• W0 indicator: 50,000 records, USB, HDX/FDX-B RFID
• Anti-backup gate to prevent exit during weighing

Step-by-step method

1. Zero the indicator (empty crate) before each session. 2. Bring a single animal into the crate. 3. Close the anti-backup gate and wait for stabilisation (≤ 3 s). 4. Validate — the W0 records weight and RFID tag automatically. 5. Release into the sorting compartment.

Throughput observed with our customers is 250–400 animals/hour with a full Scale + W0 + anti-backup chain.

Recommended frequency

Slaughter lambs: weigh at birth, 30 days, 70 days, then every 15 days until slaughter. Ewes: weigh at lambing, weaning, mating and pregnancy scanning. Rams: quarterly weighing to track body condition.

• Lambs: D0, D30, D70, then every 15 d
• Ewes: 4 key weighings/year
• Rams: quarterly weighing

Calculate ADG

ADG = (final weight − initial weight) / days. A Suffolk lamb expected at 350 g/day between 30 and 70 days that only reaches 280 g/day flags a problem: feed, parasites, insufficient milk. Regular weighing means acting before the economic loss is permanent.