Semi-arid Zone, Smallholder Farms
Typical Problems In This Area
1. Smaller farms in this zone can seldom manage to
support many animals. Feed tends to always be in short supply and animals suffer
constant nutritional stress.
2. Worm burdens often build up slowly and coupled with poor
feeding lead to a long-term chronic condition.
3. Trichostrongylus, Haemonchus and Oesophagostomum can all be
present and contribute to a generalised parasitic gastroenteritis.
4. During the dry seasons invading larvae may enter a period of
delayed development in the animal (Inhibited worms).
Features Of The Area That Can Help In Control
1. Transmission is seasonal and a significant
portion of the year is too dry for worm larvae to survive on pasture.
2. When inhibited worms are present, drug treatments can be
efficiently targeted at these.
Control Methods That May Be Useful
observation of individual animals and treating only clinical cases.
· Since rates of infection are
seasonal, treatments can be targeted at times of year when there are peaks of
· Since periods of poor grazing
and nutritional stress are seasonal, treatments can be timed to alleviate
· At certain times of year a
large part of the overall worm population is present as inhibited larvae. By
correctly applying an effective drug at this time, infection rates can be
reduced for the ensuing dry season.
· Keeping local breeds of
animals rather than exotics can lead to higher production at lower treatment