Running a successful 150-head Aberdeen Angus cross Simmental suckler herd depends on many things, foremost of which is “maximising output at minimal hassle,” according to Alistair Watson near Kirkwall in Orkney, where he farms 520 acres with father Ken and stockman Stewart Spence.
During summer months, he wants maximum growth rates in combination with minimal handling-related stress on cattle. However, taking full advantage of Orkney’s fertile soils, high annual rainfall and consequent excellent grass growth demands effective control of gastro-intestinal worms in yearling cattle that were born the previous March to June.
Indeed, SAC beef specialist Dr Basil Lowman says it is easy to underestimate the way growth rates of grazing cattle can be slowed by unseen worm infections, long before tell-tale signs of scour and dirty rumps become visible.
“Over a 200-day grazing season, unseen worm infections could easily reduce growth by 0.1 kg a day,” he says.
Of course, many wormer treatments are available, but most require cattle to be gathered, handled and treated, which inevitably creates stress and potentially disrupts growth. However, a minimum handling option is 10% moxidectin (trade name, ‘CYDECTIN® 10% LA Injection for Cattle’), administered as an injection in the back of the ear at turnout, with licensed persistency of 120 days against stomach worm (O. ostertagi) and lungworm (D. viviparus). With treatment cost in mind, dosage is weight-related and so the cost is lower in younger animals at turnout than it would be later in the year at higher weights.
Since switching to this worming strategy four years ago, Mr Watson says reality has exceeded expectations in combining minimal interference with good growth rates during the high risk summer months. “This gives us peace of mind that cattle are protected from worms throughout the grazing season,” he says.
“So we needn’t worry about additional treatments from turnout in mid May right through to October. Minimising handling like this is crucial for any cattle enterprise and keeping our workload in check. Knowing that your chosen treatment is working well is a great insurance policy on animal health, and a key factor when selling beef under Scotland’s highly respected quality assurance scheme,” he adds.
On the practical matter of administering treatment in the back of the ear, Mr Watson says the farm team quickly got used to it. “We now don’t think twice about this,” he says. “It really is very easy indeed.”
Some of the annual calf crop is sold to ScotBeef, the leading procurer of finished Aberdeen Angus cattle based in Stirling, at up to 750kg liveweight and only 20 months of age, some straight off grass and others on a housed diet of grass silage and home grown barley. Hitting these targets just wouldn’t be possible if there was a growth setback at any time from birth to finish, and Alistair Watson applies this to all cattle, whatever the outlet for his stock.
Aurelie Moralis can be contacted on 07557 076 104.