Growth and Body Composition of Artificially-Reared Lambs Exposed to Three Different Rearing Regimens

Area of Science:

• Animal Science
• Ruminant Nutrition
• Livestock Production

Background:

• Artificial rearing of lambs is common in commercial settings.
• Optimizing lamb growth and body composition requires careful consideration of feeding strategies.

Purpose of the Study:

• To investigate the effects of milk replacer composition, pellet fibre level, and weaning age on lamb growth and body composition.
• To determine the most effective and cost-efficient artificial rearing regimen for lambs.

Main Methods:

• Romney ram lambs were assigned to three treatments differing in milk replacer, weaning age (42 or 57 days), and pellet fibre content.
• Lambs were slaughtered at 57 days of age for carcass and body composition analysis.

Main Results:

• No significant differences in average daily liveweight gain were observed across treatments.
• Higher carcass weight, dressing percentage, and omental fat were noted in lambs weaned later (57 days).
• Early-weaned lambs (42 days) showed higher whole-body protein content and lower fat deposition.

Conclusions:

• Weaning lambs at 42 days with either low or high fibre pellets supports similar growth rates compared to later weaning.
• Early weaning at 42 days reduces fat deposition and is a more cost-effective rearing method.
• Dietary strategies can be adjusted to optimize lamb body composition during artificial rearing.