High winter feed costs for beef and heifer rearers could be offset by good choice in summer-long worming strategy, according to Pfizer VPS vet David Bartram.
He says maximising growth rates at grass can allow feed cost economies next winter. Otherwise, many farmers are forced to compensate for poor weight gain at grass by pushing for unduly high growth rates during the next housing period.
EBLEX consultant Charlie Morgan says growth rates of 1.2kg/day are achievable in May and June with good management practices. However, when 0.5kg/day of potential growth is lost over a six-month grazing season, then 90kg of catch-up growth could be necessary next winter.
At 10:1 feed conversion, he says this would require 900kg of feed, which at £160/tonne would cost £144/head. On the other hand, he suggests optimising growth over the whole grazing season, thereby avoiding the need to feed so heavily could help save most or all of this potential cost.
Among the management tactics required for optimising live-weight gains at grass, an important one is season-long worm control, Mr Bartram says.
“Worm infections can reduce summer growth rates well before visible signs are present,” he explains. “So adopting a season-long control plan can make a worthwhile impact on rearing costs.”
When the convenience of a single treatment at turnout is wanted, Mr Bartram advises either a pulse-release oxfendazole bolus or long-acting 10% moxidectin injection given into the back of the ear.
For farmers who prefer a pour-on formulation, he says 0.5% moxidectin treatments at turnout and then eight to 10 weeks later will normally provide whole-season cover. “In addition to killing worms, all these options can allow sufficient exposure to worms for the development of natural immunity,” Mr Bartram adds.
To ensure season-long protection using the dosing strategies suggested, cattle must be set-stocked for the entire grazing season. For specific advice about choice of worming programme, farmers are advised to consult their vet.