Where animals are fed to grow fast in the winter based on high concentrate feeding their performance at pasture can be somewhat disappointing.
This has been confirmed by latest research in Teagasc Grange on the effect of weanling winter growth rates on subsequent performance.
Outlining some of the results of the research at the National Beef Conference, Teagasc’s Edward O’Riordan said in the study, 120 spring-born Charolais- and Limousin-sired weaned suckled bulls, ~9 months of age, with an average weight of 370kg and a birth date of March 8, were used.
They were placed on:
(1) grass silage diet offered ad libitum (DMD 731g/kg) supplemented with 2kg concentrate daily.
(2) the same grass silage supplemented with 4kg concentrate daily.
(3) the same grass silage supplemented with 6kg concentrate daily.
At the end of the 123-day winter, bulls were turned out to pasture for ~100 days, where they rotationally grazed a predominantly perennial ryegrass pasture in group sizes of 20, and stocked at ~6 bulls/ha.
According to O’Riordan, at end of the winter if you’re producing weanlings for sale it left you a margin by feeding concentrate up to 4kg.
“If you sell those weanlings you’re are being paid for the additional weight you put on the animal over the winter.
“The person who buys them off you might not be too pleased because they will get a poorer response at pasture due to your higher level of feeding, he said.
According to O’Riordan, if you’re keeping weanlings for yourself then the optimum level of feeding is seldom much more than 2kg/head/day over the winter and he said quite often it’s less than that.
“If you’re selling weanlings you may be justified in feediing more than the 2kg.
“However, if you’re buying a fancy weanling driven on by concentrates you might be dissapointed with the actual responce.
“Where animals are fed to grow fast in the winter, based on high concentrate feeding their performance at pasture can be somewhat dissapointing,” he said.