Parasitology slide set 3 Flashcards
Two major divisions of arthropods in terms of pesticides
Insects (fleas, lice, flies)
Ticks and mites
In some products there are synergists (like piperonyl butoxide or N-octyl bicycloheptene dicarboximide) are used to
slow pesticide breakdown, so NOT pesticides
Types of arthropod control agents
Pesticides- kill outright, interfere with normal growth and development
Biological control- eparasitic wasps
Physical control- fly mask
Pyrethrins
botanicals- plant products, quickly metabolized
Mode of action of pyrethrins
Disrupt ion transport in nerve membranes
Paralysis of organism; quick knockdown, some repellent activity
Often used with synergists to prevent detoxification
Spectrum of action of pyrethrins
many species
Toxicity of pyrethrins
Pretty safe b/c rapidly metabolized
Problems can occur is animal ingests too much: salivation, diarrhea, vomiting, trembling
Method of application of pyrethrins
Topical, not absorbed (sprays, dusts, shampoos)
Members of pyrethroids
permethrin (most common, bad for cats), cyfluthrin, lamdacyhalothrin, beta-cyfluthrin, flumethrin, etofenprox (common in OTC cat flea products)
Most generic names end in -thrin
Mode of action of pyrethroids
Similar to pyrethrins, cause paralysis of organism
Some repellant activity but not primary mode of action
Toxicity of pyrethroids
Similar to pyrethrins, but can be worse b/c more potent and last longer
Need to know if product is pyrethrin or pyrethroid
Method of administration of pyrethroids
Topical- lipophilic (helps them stay around), dusts, sprays, shampoos, spot-ons, etc (ex. advantix 2)
Enviromental- pyrethriods
Members of neonicotinoids (chloronicotinyls, nitroguanidines)
Imidacloprid
Nitenpyram
Dinofuran
Spectrum of action of neonicotinoids
Insects on animals and plants
Mode of action of neonicotinoids
Binds to nicotinic acetylcholine receptors in insects
Toxicity of neonicotinoids
Low toxicity b/c mammalian receptors different, would expect nicotinic signs if occured
Method of administration of neonicotinoids
Topically, mostly (capstar is an example of an oral admin)
Spectrum of action of macrolides (macrocyclic lactones)
Variable efficacy against many arthropod species
Method of administration of macrolides
Oral, spot-ons, injection, feed additives
Best product for ectoparasites applied to skin
Topical ones are absorbed systemically
Members of spinosyns
spinosad
spinetoram
Spectrum of action of spinosyns
Insects
Mode of action of spinosyns
Activates nicotinic acetylcholine receptors so act like neonicotinoids but the receptor is different
Toxicity of spinosyns
Appears low
Administration of spinosyns
oral and topical
Member of phenylpyrazoles
Fipronil (frontline plus)
Spectrum of phenylpyrazoles
Insects, ticks, mites
Toxicity of phenylpyrazoles
Doesn’t seem to bind to mammalian receptors generally
Don’t use in rabbits
Toxic for fish, aquatic systems
Mode of action of phenylpyrazoles
Binds to GABA receptors, inhibits ion flux in nerve cells- hyperexcitability and death
Member of formamidines
Amitraz
Spectrum of formamidines
Ticks and mites primarily
Mode of action of formamidines
Monoamine oxidase inhibitor
Toxicity of formamidines
do NOT use in horses, relatively safe in others
Lethargy, hypotension, vomiting
Method of administration of formamidines
Topical, not absorbed
Member of oxadiazine
indoxacarb (this is a new product, activyl for cats)
Spectrum of action of oxadiazine
Insects
Mode of action of oxadiazine
Sodium ion channel blocker affects neuromuscular system
Safety of oxadiazine
doesn’t bind mammal sodium channels so safety is good
Carbamates mode of action
Inhibit acetylcholinesterase in vertebrates and invertibrates
Effects are more reversible and so safer then organophosphates
Members of carbamates
Carbaryl
Propoxur
Safety of carbamates
Can cause toxicity if overdosed
Salivation, lacrimation, urination, diarrhea
Respiratory failure
Environmental and plant pesticides include some used on animals
fipronil, imidicloprid, dinotefuran, spinosad
Lime sulfur
smelly but pretty safe, used in small animals
Repellents- human products, not used in animals
DEET
Picardin (oil of lemon eucalyptus)
“Natural” products
D-limonene, high dose can be toxic
Herbal preparations- little efficacy or toxicity data
Insect development inhibitors
chitin synthesis inhibitors
Example: lefenuron (program)
Insect growth regulators
Juvenile hormone analogs
Examples: methoprene (frontline plus); pyriproxyfen (knockout, vectra 3-d)
Toxicity of IDIs and IGRs
low
Administration of IDIs and IGRs
topical
environmental
NOT QUIZ
Antibacterials are used also as
antiprotozoals
NOT QUIZ
Sulfonamides
inhibit folic acid production
used for treatment of coccidian parasites
NOT QUIZ
Nitroimidazoes
Interfere with RNA synthesis
Metronidazole used for treatment of giardia
NOT QUIZ
Ionophores
Destroy cross-membrane ion gradients
Monensin, lasalocid
Used for prevention of coccidiosis
NOT QUIZ
Antibacterial macrolides
Inhibits protein synthesis
Clindamycin
Used for treatment of toxoplasma infection
NOT QUIZ
Triazones
Inhibit nuclear division
Diclazuril, ponazuril
For coccidiosis in poultry and EPM in horses
NOT QUIZ
Pyridine derivative
Interfere with mitochondrial metabolism
Decoquinate
For coccidiosis in food animals, poultry
NOT QUIZ
Pyrimidine derivatives
Amprolium- competitive thiamine antagonist
For treatment and prevention of coccidiosis in poultry and food animals
NOT QUIZ
Benzimidazoles
ABZ, FBZ, used for giardia
