Farm Table says:
What is the problem?
This study was conducted to evaluate the relationships among ewe milk yield, as affected by dietary energy level, pre- and post-weaning performance, and carcass traits of early-weaned lambs.
What did the research involve?
- Three diets with different levels of metabolizable energy (ME; 10.3, 10.9, and 11.5 MJ/kg) were fed to lactating ewes to study the relationships among milk yield and feed intake, growth rate, and carcass traits of early-weaned lambs.
- Eighteen Texel × Ile de France ewes (55.7 ± 1.3 kg of initial body weight) supporting single male lambs were penned individually at 24 h after lambing and evaluated for 42 days.
- Lambs had free access to a creep feeding system before weaning (42 days of age), and after that, they were individually penned and fed a common diet until reaching the slaughter weight (32 kg of BW).
- Carcasses were then evaluated after 24 h of refrigeration.
What were the key findings?
- Dry matter and ME intake of ewes presented a quadratic relationship with an energy level of the diet, and it directly affected milk yield.
- Milk yield was correlated with DM intake and growth rate of lambs from birth to weaning.
- On the other hand, in this period there was no relationship between solid feed intake and ADG of lambs.
- From weaning to slaughter, DM intake of lambs was greater for the lambs raised by ewes in the low-energy group, resulting in a worse feed efficiency.
Therefore, creep feed supplementation was not enough to support a similar growth rate among lambs ingesting different amounts of milk. No remarkable changes were observed in carcass traits.
The study concluded that improving ewe nutrition and consequently the early life nutrition of lambs can really increase the profitability of lamb meat production.
Milk intake is the main factor affecting growth performance of early-weaned lambs. Therefore, improving ewe nutrition during the lactation period is an efficient way to increase growth performance of lambs in their initial stage of development. Moreover, increasing lamb performance from birth to weaning results in a great post-weaning feed efficiency and reduces feeding costs when considering the entire production cycle of sheep meat.