LFP 211: Livestock Farm Practice (0+1)

CONTROL OF INTERNAL PARASITES

• The adult endoparasites (round worms, tape worms and flukes) live in the main host and lay large number of eggs that are voided outside through the excreta of the hosts.
• The tremetode eggs, under optimal conditions of temperature and humidity hatch out. The resulting larvae generally enter an intermediate host (fresh water or land snails, slugs, ants, insects, beetles, crustaceans, man, pig etc.).
• The infective forms of the larvae after coming out of the intermediate host harbor themselves on herbage to be grazed by animals. The eggs of round worms under optimal conditions hatches and become infective stages. They enter the final host along with contaminated fodder, water, feed, etc. There won’t be any intermediate host.
• In the case of cestodes, they invariably have a stage in the intermediate host and when final host ingests the body of intermediate host harboring the intermediate stage, they pick up the infection. In case of some round worms (about one-third of those affecting animals), the parasites follow the same cycle with the exception that there is no intermediate host.
• The eggs voided out hatch under optimal conditions and the infective forms settle on herbage.
• Thus, control of internal parasites should be aimed at
  • ridding the animal of internal parasites by periodical deworming,
  • preventing infestation of animals by keeping premises free from infective forms of parasite – disinfestation, and
  • elimination of intermediate hosts.