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Figure
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.
Figure
Typical Problems In This Area
1. At certain times of year, because of high temperature and humidity, worm eggs develop to the infectious stages very quickly, so problems can build up rapidly.2. Because of the relatively cool conditions at this altitude, pasture can remain infective for long periods after it has been last grazed.
3. There are many liver fluke transmission sites.
Features Of The Area That Can Help In Control
1. Farms are often larger than in other areas, so it can be possible for farmers to manage rotational systems.2. Farms in this area tend to be well developed and have good grazing management.
3. Cattle are often present in numbers which can permit alternate grazing systems to be effective.
Control Methods That May Be Useful
· Frequent observation of individual animals and treating only clinical cases.· A Dose & Move system where all animals in the flock/herd are treated and moved onto clean ground.
· 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.
Figure
Typical Problems In This Area
1. The weather conditions are suitable for transmission of stomach and intestinal worms throughout the year, so worm numbers can be high.2. Because of the relatively cool conditions at this altitude, pasture can remain infective for long periods after it has been last grazed.
3. Liver fluke is present in valley bottoms.
4. SEVERE RISK OF ANTHELMINTIC RESISTANCE.
Features Of The Area That Can Help In Control
1. Farms are often larger than in other areas, so it can be possible for farmers to manage rotational systems.2. Cattle are often present in numbers which can permit alternate grazing systems to be effective.
3. Rapid grass growth can enable cut and carry systems of animal feeding to be effective.
Control Methods That May Be Useful
· Frequent observation of individual animals and treating only clinical cases.· Adult cattle can graze areas after sheep, goats or calves in an alternate grazing system.
· 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).
· Medicated feed blocks can be made with locally available ingredients and provided to the animals overnight in the boma.
· Cut and carry systems can prevent animals grazing and contaminating pasture.
· GUIDELINES FOR USE OF ANTHELMINTICS SHOULD BE CAREFULLY FOLLOWED TO SLOW THE DEVELOPMENT OF ANTHELMINTIC RESISTANCE.
Figure
Typical Problems In This Area
1. High grazing pressure means that transmission rates can be high and there are few opportunities to control worms by grazing management.2. Because of the relatively cool conditions at this altitude, pasture can remain infective for long periods after it has been last grazed.
3. There are many liver fluke transmission sites.
4. 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.
5. The presence of both Haemonchus and liver fluke can lead to a chronic syndrome (which can become worse during periods of poor feeding).
Features Of The Area That Can Help In Control
1. Worm challenge rates vary with the season and periods of peak infection occur during or shortly after the rains.2. 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.· Since rates of infection are seasonal, treatments can be targeted at times of year when there are peaks of infection.
· Since periods of poor grazing and nutritional stress are seasonal, treatments can be timed to alleviate chronic infections.
· Mixed use of broad and narrow spectrum drugs can help control Haemonchus and liver fluke.
· Medicated feed blocks can be made with locally available ingredients and provided to the animals overnight in the boma.
· Specific treatments to control liver fluke can be applied at times of year when these are most likely to be effective.
Figure
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
· Frequent 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 infection.
· Since periods of poor grazing and nutritional stress are seasonal, treatments can be timed to alleviate chronic infections.
· 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 costs (Genetic Resistance).
Figure
Typical Problems In This Area
1. 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.2. Worm burdens often build up slowly and coupled with poor feeding lead to a 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).
5. Although overall stocking rates may be low, these can be locally high around watering points and bomas.
6. Toxocara may be a problem in young suckling calves.
7. Coenuriasis may be quite common in sheep and goats.
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.
3. Overall stocking rates are low.
4. There is little need for frequent anthelmintic treatments, so risk of developing anthelmintic resistance is low.
5. Most stock kept are of indigenous, worm-resistant breeds.
Control Methods That May Be Useful
· Frequent 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 infection.
· Since periods of poor grazing and nutritional stress are seasonal, treatments can be timed to alleviate chronic infections.
· 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. (treatment against inhibited worms).
· Keeping local breeds of animals rather than exotics can lead to higher production at lower treatment costs (Genetic Resistance).
· Specific treatments to control Toxocara may need to be carried out where this is a persistent problem.
Figure
Typical Problems In This Area
1. 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.2. Worm burdens often build up slowly and coupled with poor feeding lead to a 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 (see Inhibited worms).
5. Although overall stocking rates may be low, these can be locally high around watering points and bomas.
6. SEVERE RISK OF DEVELOPING AND DISSEMINATING ANTHELMINTIC RESISTANCE.
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.
3. Overall stocking rates are low.
4. Presence of infrastructure can permit managed lambing and grazing management.
Control Methods That May Be Useful
· Frequent observation of individual animals and treating only clinical cases.· Seasonal, treatments can be targeted at:
times of peak infection.
inhibited worms.
chronic infections.
· Crossing local breeds of animals rather than keeping pure-bred exotics can lead to sustainable production at lower treatment costs (Genetic Resistance).· A Dose & Move system where all animals in the flock/herd are treated and moved onto clean ground.
· Regular movement of bomas can prevent local build up of infection on pasture (Boma Rotation).
· Use of narrow spectrum drugs can reduce the reliance on broad spectrum anthelmintics and slow the development of anthelmintic resistance
Figure
Typical Problems In This Area
1. 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.2. Although overall stocking rates may be low, these can be locally high around watering points and bomas.
3. Coenuriasis and hydatid are common.
4. Worm burdens often build up slowly and coupled with poor feeding lead to a chronic condition.
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.
3. Overall stocking rates are very low.
4. Larvae do not survive long.
5. Most stock kept are of indigenous, worm-resistant breeds.
Control Methods That May Be Useful
· Frequent observation of individual animals and treating only clinical cases.· Seasonal, treatments can be targeted at:
times of peak infection.
inhibited worms.
chronic infections.
· Keeping local breeds of animals rather than exotics can lead to higher production at lower treatment costs (Genetic Resistance).
Figure
Typical Problems In This Area
1. The weather conditions are suitable for transmission of stomach and intestinal worms throughout the year, so worm numbers can be high.2. Because of the high temperature and humidity, worm eggs develop to the infectious stages very quickly, so problems can build up rapidly.
3. There are high rates of Haemonchus, Trichostrongylus and Oesophagostomum.
4. Sites for transmission of liver fluke are common.
5. Both clinical and chronic worm infections are made worse by the presence of trypanosomiasis. Care is needed in deciding a cause for anaemia.
6. Mixed infections of fluke, roundworms and trypanosomes can occur.
7. SEVERE RISK OF ANTHELMINTIC RESISTANCE.
Features Of The Area That Can Help In Control
1. Due to the high temperatures, larvae do not survive very long on pasture.2. If ground is kept completely free of animals for a period of four weeks it will be clean.
3. The presence of palm trees can help in providing evenly spaced tethering points for use in a rotational grazing system
Control Methods That May Be Useful
· Frequent observation of individual animals and treating only clinical cases.· Rapid Rotation around a series of paddocks or tethering points.
· A Dose & Move system where all animals in the flock/herd are treated and moved onto clean ground.
· Medicated feed blocks can be made with locally available ingredients and provided to the animals overnight in the boma.
· Keeping local breeds of animals rather than exotics can lead to higher production at lower treatment costs (Genetic Resistance).
· GUIDELINES FOR USE OF ANTHELMINTICS SHOULD BE CAREFULLY FOLLOWED TO SLOW THE DEVELOPMENT OF ANTHELMINTIC RESISTANCE.
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