Using a lamb's early-life liveweight as a predictor of carcass quality

Area of Science:

• Agricultural Science
• Animal Science
• Livestock Production

Background:

• Lamb carcass value depends on weight and quality (muscle, fat depth).
• Predicting carcass quality early aids flock management for producers.
• Current prediction methods are costly or require pre-slaughter data, limiting their use.

Purpose of the Study:

• To assess the feasibility of predicting lamb carcass quality using early-life liveweight.
• To determine if weaning weight can predict carcass leanness and muscle coverage.
• To evaluate the economic implications of using weaning weight for carcass quality prediction.

Main Methods:

• Utilized seven-year high-resolution data from the North Wyke Farm Platform grazing trial.
• Employed multinomial regression models to analyze the relationship between weaning weight and carcass traits.
• Conducted an economic analysis considering seasonal lamb price variations.

Main Results:

• Lambs heavier at weaning (13 weeks) were significantly more likely to yield leaner, more muscular carcasses.
• These heavier-weaned lambs resulted in significantly more valuable carcasses at slaughter.
• Increased average weaning weight can improve pasture availability and ewe condition/fertility for the next season.

Conclusions:

• Early-life liveweight, specifically weaning weight, is a reliable predictor of lamb carcass quality.
• Focusing on ewe nutrition during pre- and lactational periods is key to enhancing system-wide profitability.
• This approach offers a cost-effective decision support tool for sheep producers.