Chicks and ticks
The humble domestic chicken could help farmers more than they suspect with pest control and, without much effort, could do more. Within a matter of hours chickens can consume hundreds of a major livestock pest - ticks. And, by matching the management and movement of their cattle and poultry to the daily rhythm of tick activity, farmers can turn this taste for ticks to their advantage.
This is just one of the many environmentally friendly methods of
tick control being explored by scientists at ICIPE (International
Centre for Insect Physiology and Ecology). Alternative,
environmentally safe and yet effective methods of control are
obviously highly desirable and chickens are by no means the only
answer. 
For
some years ICIPE scientists have been working on ways to make use of a
natural parasitic wasp which lays its eggs inside the tick and, when
the larvae emerge, they consume the tick from within. Other organic
methods of control include the use of neem, already used successfully
by farmers in India, Australia and elsewhere, and fungal pathogens.
The fungi can be sprayed directly on to the ticks as they feed on the
host animals, or on to the vegetation where ticks spend up to 95% of
their time.
Vaccination is not usually associated with the control of such a comparatively large organism as a tick but it seems it could work. By using glycoprotein from the gut of the tick, and from this developing a vaccine, scientists at ICIPE have found that the vaccinated cattle develop antibodies which are ingested when the ticks feed on the host animal. As a result, the ticks may either die or, at the very least, they cannot feed properly and so lose weight and lay fewer eggs. Such a treatment, when fully developed, could prove of great benefit to commercial farmers but, for small farmers, there are many simple, good husbandry practices that help to reduce the tick load.
Ticks, like most organisms - including humans - are more active at certain times of day than others. They show two peaks of activity, one in the morning and one in the afternoon. Farmers could, therefore, avoid grazing their animals when ticks are most likely to attack. Of course, this timing may not necessarily fit in with other work and may not be possible to arrange. Nevertheless, studies of the tick's preferred lifestyle are very useful. For example, they tend to drop off animals at a specific time of day. If, at this time, cattle can be brought to one place, the ticks can be treated while on the vegetation, by spraying with pathogenic fungi, for example, or by using scavenging tick-devouring chickens.
