Correct housing vital for top performance
AVOIDING injuries and pneumonia and maximising Holstein bull performance depends on adapting housing to suit the animals requirements.
Poor ventilation led to an outbreak of pneumonia in Dungannon Meats Holstein cattle trials leading to six casualties, said Greenmount Colleges Frank Foster.
"Improving ventilation meant leaving an inch space between roof sheets and removing some side sheets to allow air to circulate above cattle heads. This allowed them to recover."
Bulls on an intensive cereal-based system also required better ventilation to maintain performance than steers or heifers on a silage-based system, according to Mr Foster.
"These animals have one-and-a-half times the oxygen requirement of a 500kg bullock eating silage. High levels of liveweight gain require high levels of oxygen.
"A 500kg bullock requires 0.075sq m of air inlet area and 0.045sq m of air outlet area compared with a bull of the same weight, which needs 0.12sq m of air inlet area and 0.06sq m of air outlet area."
As well as disease, housing also needed adjustment to minimise injuries, he said. "From five to six months, bulls begin to develop bullish characteristics such as mounting, which can lead to injury.
"Putting electric wires across the top of pens discourages mounting, reducing injuries. Mixing animals should also be avoided as it leads to aggression and injury.
"Allow animals sufficient space when they enter the system to avoid having to mix groups later. This should be based on their mature weight – 2.1 sq m/500kg," said Mr Foster.