Can oats, beans or peas play a role in beef cattle diets?
A recent trial in Teagasc Grange evaluated the role oats, field beans or peas can play when used in the rations offered to beef cattle on grass silage diets.
The study aimed to examine how animal performance, nitrogen excretions and feed costs were impacted upon when various energy and protein sources were used. The results of which have recently been published in the Journal of Animals.
Experiment 1
The first experiment, consisting of 80 steers – balanced for live weight and sire breed – and taking place over 110 days, compared the levels of performance achieved when animals were offered a rolled barley or maize meal based ration with four differing protein supplements – flaked peas, flaked field beans, maize distillers or maize gluten feed. Steers were assigned to one of the eight treatments over the duration of the experiment.
The eight rations offered, fed at 4kg/head/day, were designed to have similar crude protein concentrations. The overall energy densities of the diets were also similar in UFL terms. The researchers found that there were no interactions between cereal type (maize versus rolled barley) and protein source for animal dry matter intake, performance or carcass traits.
Experiment 2
A second experiment evaluated the levels of performance achieved when rolled barley or rolled oats was used as the energy source, with rations formulated both with and without flaked beans or flaked peas to examine how including or excluding these protein sources affected animal performance.
Involving 72 steers, again balanced on live weight and sire breed, this experiment took place over 146 days, throughout which grass silage with a moderately high crude protein concentration was offered ad-lib. Six concentrate treatments were involved, with animals assigned to one of the feeding treatments throughout the duration of the experiment.
As intended, the crude protein concentrations of the cereal only rations (rolled oats (111g/kg DM) or rolled barley (120kg/kg DM)) were lower than those supplemented with either flaked beans or flaked peas, which had a mean concentration of 149 g/kg DM. Again, like experiment one, the energy densities of the total diets were estimated to have been similar.
From this experiment, the researchers found that there were no interactions between cereal type and protein source on the animal’s dry matter intake or carcass traits. Grass silage dry matter intake, total dry matter intake and total dry matter intake relative to live weight, daily live weight gain, feed conversion efficiency, slaughter weight, kill-out proportion, carcass weight, estimated carcass gain, carcass conformation score and carcass fat score did not differ between the cereal types or protein source, except for peas where there was a tendency for a reduction in daily live weight gain, feed conversion efficiency, slaughter weight, carcass weight and carcass conformation score compared to beans and the cereal only rations.
Conclusion
Concluding on the results of this study, the authors noted that the feeding value of rolled barley was similar to oats and maize meal, and flaked beans and peas were similar to maize gluten feed and maize distillers, as supplements to grass silage. The latter may decrease the dependence on imported feed ingredients.
Excluding protein ingredeints from a cereal-based concentrate, where grass silage with a moderately high crude protein concentration was offered, did not affect animal performance and reduced nitrogen excretion.
For full access of the paper titled: Intake, Growth and Carcass Traits of Steers Offered Grass Silage and Concentrates Based on Contrasting Cereal Grain Types Supplemented with Field Beans, Peas or Maize By-Products, co-written by Rian Kennedy, Aidan Moloney, Edward O’Riordan, Alan Kelly and Mark McGee, click here.