Control of Parasites Flashcards
what are antiparasitic chemicals?
types of antimicrobials with crossover with antibacterial and antifungal chemical agents
what do antiparasitic chemicals do? (3)
- interfere with metabolism
- interfere with reproduction
- interfere with growth of parasitic agents
what do antinematode agents specifically do?
affect adult reproduction so eggs can’t hatch and there are no larvae to continue the cycle
what is the risk of using antiparasitic agents and why?
they have low selective toxicity because the eukaryotic parasite cells are very similar to our own eukaryotic cells, so there are extensive side effects
what are the main kinds of antiprotozoals?
coccidiostats
what do coccidostats work against? (coccidia types)
eimeria and isospora!!
what are the 2 groups of coccidiostats?
- polyetherionophore antibiotics: like monensin
2. nonpolyetherionophore antibiotics/synthetics/chemicals
what do polyetherionophores do?
target ion channels to disrupt movement of ions across cell membranes, leading to an osmotic pressure imbalance that causes coccidia to die
what is standard practice to avoid resistance to coccidiostats?
rotate between polyetherionophores and nonpolyetherionophores
what Kind of effect does monensin, a polyetherionophore, have? how?
increases permeability in coccidia cell membranes to create an antibacterial effect
in what 4 animals is monensin widely used preventatively?
- rabbits
- poultry
- swine
- ruminants
how is monensin used in the US? why?
as a feed additive as a promotor of growth and feed conversion efficiency; the antibacterial effect leads to more efficient digestion
how is monensin used in the EU?
only in poultry and rabbits where coccidiosis is systemic/widespread problem
in what animals in monensin highly toxic?
horses
what 2 things are countries trying to figure out with monensin? answer those questions
- is monensin absorbed in meat/does it enter food? research says no because it can’t get inside of cells, can only target free-living parasites
- is coccidia becoming resistant to monensin? it IS becoming an issue, so we have to be very careful in our usage (@US)
where was most of the control of ectoparasites developed from?
pesticides on crops
what are the 2 types of ectoparasite situations that determine how we treat it? tell how treat
- parasites that live permanently in the host; we can treat the host directly
- parasites that have only one life stage in the host; need to combine control of parasites and environment