|Integrated Helminth Control - KARI technical note no. 2 (DFID - KARI, 1999, 54 p.)|
|PART TWO - Helminth Control Advice, summarised by area|
Typical Problems In This Area
1. Because of the high temperature and humidity, worm eggs develop to the infectious stages very quickly, so problems can build up rapidly.
2. Due to the uneven distribution of rainfall during the year, there are times when grazing is in short supply and animals suffer from nutritional stress.
Features Of The Area That Can Help In Control
1. Anthelmintic resistance is currently rare due to low previous rates of drug use.
2. Although larvae develop quickly in this humid zone, they do not survive as long on pasture as they might in a cooler area. Where pasture can be left ungrazed for 5-6 weeks, the majority of larvae will have died.
3. Larvae on pasture survive best when the grass is still green. During periods when grass growth has stopped, larvae rapidly begin to die.
Control Methods That May Be Useful
· Frequent observation of individual animals and treating only clinical cases.
· Fresh grass grown after a crop has been harvested will be clean. A rotation of cropping and grazing areas can provide constant availability of clean grass (Cropping Rotation).
· Since rates of infection are seasonal, treatments can be targeted at times of year when there are peaks of infection.
· Keeping local breeds of animals rather than exotics can lead to higher production at lower treatment costs (Genetic Resistance).
· Since periods of poor grazing and nutritional stress are seasonal, treatments can be timed to alleviate chronic infections.
· Medicated feed blocks can be made with locally available ingredients and provided to the animals overnight in the boma.