LESS STRESS IN JET SET…
By Rebecca Austin
DIPPING sheep using a New Zealand-designed Hi-Flo Jetter is both safer for the operator and less stressful to sheep, says Wilts-based sheep contractor Bob Blanden.
The jetter, which can "dip" over 500 sheep an hour, fits into a handling race and is fully mobile. As the sheep pass into the crate they press against spring-loaded, adjustable bars which release a valve.
When this happens the two pipes on top of the crate and one on each side – as well as one on the floor – spray dip on to the sheep. In all, 2-3 litres of dip will cover each sheep from the four jets.
As a result, less dip is required for the same number of sheep, compared with plunge dipping. "The residual amount collected in a tank under the crate is less because nearly all the dip used goes off with the sheep," explains Mr Blanden. The ratio of dip to water is the same as used when topping up a conventional dip.
The design varies from that used in New Zealand. For a start, a ramp is set at a slight gradient for sheep entering the crate. "This slows them down so that they dont rush through the dip too quickly, although it is important they flow through," says Mr Blanden.
With health and safety regulations in mind, he is also covering the crated area to prevent spray drift. "Even without that the great advantage of this equipment is the remoteness of the operator," he says. "The nearest he is likely to be to the jetter is in the collecting area guiding sheep into the race."
Compared with plunge dipping, he also claims savings in time and labour. "When using the jetter in New Zealand one man and his dogs can do the whole job. There is no need for anybody to stand near the sheep when they are jetted, as compared with plunge dipping, so the job is much easier for both sheep and shepherds."
The mobile jetters advantage over pour-ons becomes apparent when costs are compared. On average pour-ons cost about 50p/head. Contracting charges for the jetter will be less, although an exact price has yet to be agreed. "To be attractive to farmers the cost will also be cheaper than calling in a contractor to plunge dip the flock against fly strike," says Mr Blanden.
The jetter, which is commercially available for the first time this summer, is only seen as an alternative to plunge dipping for flies, lice, keds and ticks. It will not control scab, which requires complete submersion if the mite is to be destroyed.
"I can see this system as being very useful to those producers which run large commercial flocks," says Mr Blanden. "Since compulsory dipping stopped in 1992 the number of sheep I dip has dropped by 60,000 to 20,000. Some of those who have opted out will have changed to pour-ons, but just how many arent bothering to dip any longer? This system will be an attractive alternative for those people."
Although Mr Blanden expects other contractors will be most interested in acquiring a jetter, it will also be available to individual producers. But Mr Blanden stipulates he will not supply the jetter without the 5hp pump. "It is integral to the system. Any old pump wouldnt be able to do the job. Most sheep producers in Australia and New Zealand have a fire-fighting pump on their station which doubles up at dipping time."
The Hi-Flo Jetter is based on a New Zealand design and is commercially available for the first time this summer. Right: Bob Blanden.