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Pig keeping in the tropics - part 6

Diseases, prevention and control Local breeds are often resistant to diseases. The main problem with keeping any sort of pig in free-range or semi-intensive systems is not disease but disabling infestation by worms or other parasites. It is in intensive pig keeping systems that disease is a greater risk | 7 Diseases prevention and control Local breeds are often resistant to diseases. The main problem with keeping any sort of pig in free-range or semi-intensive systems is not disease but disabling infestation by worms or other parasites. It is in intensive pig keeping systems that disease is a greater risk because many animals are kept together in a small space. Infectious diseases spread easily and quickly among the animals. In intensive systems commercial breeds are often used and these tend to be less resistant to disease. Intensive pig production is a financial undertaking. Diseases can lead to production shortfalls slower growth rates or loss of animals and a loss of income for the farmer. In these circumstances it is essential to treat the animals as long as the costs of treatment do not exceed the loss of income expected. In free-range and semi-intensive systems farmers do not generally have funds to spend on medical treatment. It is also possible that the pigs are not their only source of income. In such cases a drop in production may be viewed as less important and farmers may wish to calculate whether the benefits of saving the sick animal and protecting the others justify the cost of treatment. In terms of prevention if there is a high risk of an infectious disease occurring animals can be vaccinated to reduce the risk of losing them all if a disease breaks out. Whatever the circumstances if at all possible the advice of a vet should be sought if there is disease on the holding. Despite all preventive efforts treatment with medicines may be the only solution remaining. 64 Pig keeping in the tropics 7.1 Prevention by promoting natural resistance Many diseases and health-related problems in animals can be linked to a loss of natural resistance as a result of feeding problems a lack of hygiene or sudden changes in their environment e.g. temperature humidity . Many problems can be prevented by taking the following measures Ensure that the pigs receive .