Parasites, Toxins, Antibiotics

Organophosphate

AChE inhibitor - SLUDGE signs

tx = atropine or 2PAM

pyrethrins

cat given dog flea product

affects sodium channels - SLUDGE signs

tx = methocarbamol

rodenticides/anticoagulants

warfarin, brodifacoum

affects factors 2, 7, 9 and 10

PT prolongs soonest

treatment = vitK

bromethalin

causes demyleination, cerebral edema

cholecalciferol

vitD3 - increases Ca and P absorption, nephrotoxicity

tx = furosemide, pred

strychnine (snail bait)

glycine inhibitor

affects striated muscle

tx = methocarbamol

ethylene glycol

AKI, GI distress, metabolic acidosis, Ca oxalate crystals

tx = fomepizole, 4MP > ethanol

marijuana

hyperesthesia, ataxia, incontinence

ibuprofen

GI upset, renal failure, neuro signs at high doses

see tubular casts, proteinura

extra bad in cats and ferrets

aspirin

decreased platelet function

hepatotoxic

hyperthermia

seizures

chocolate (methylxanthines)

tachycardia

VPCs

seizures

CNS

xylitol

rapid insulin release leading to decreased BG

liver failure, increased clotting times, hypokalemia

tx = fluids with dextrose

heinz body anemia toxins

acetominophen (esp cats)

zinc (pennies past 1983)

onions/garlic (Allium species)

red maple (acer rubrum)

acetominophen tx

N-acetylcystine

NO steroids or antihistamines

grapes

v/d, abdominal pain, PU/PD

azotemia

lillies

AKI/acute renal failure

Ca oxalate, elevated P and K, creat > BUN

black widow spider

binds Ca channels - ascending motor paralysis

death is due to cardio/resp failure

recluse

painless, bullseye lesion

no worries

crotalids

rattlesnake, copperhead, cottonmouth

swelling, bruising, necrosis, cagulopathy

elapids

coral snakes

CNS depression, respiratory paralysis

lead

dog - GI upset

cow - eyelid twitch, bruxism, blind, convulsions

horse - roaring, stridor, dysphagia

tx = Ca EDTA (succimer)

lead on blood smear

nRBCs without anemia

basophilic stippling

selenium

oversupplementation leads to oxidative injury

peracute death, ascending paralysis

tx = N-acetyl in horses, prevention in cows

salt toxicity

brain draws water in leading to neuro signs

hemolysis if rehydrate too fast!

copper

sheep given cow/horse food

hemolytic anemia, icterus, methemoglobinemia, "gun metal" kidneys

tx = molybdenum

copper deficiency

enzootic ataxia in lambs

swayback (ascending paralysis)

nitrate

drought, fertilizer, herbicide

blood is brown (methem)

tx = methylene blue

arsenic

contaminated water, soil, lumber

acute ataxia/paralysis, GI, cardio, neuro

tx = Na thiosulfate

urea/NPN

CNS, sudden death, rumen pH >8

mycotoxins (list)

zearalenone

slafranine

Fescue/ergot/claviceps

blue green algae/cyanobacteria

fumonisin

aflatoxin (aspergillus)

zearalenone

pigs with repro disease

elevated estrogen, pseudopregnancy

slafranine

moldy red clover

slobbers

Fescue tox

endophyte grows on the grass creating ergot (claviceps = parasitic fungus)

summer slump - can't thermoregulate

fescue foot - distal limb sloughing

repro - dysgalactia, long gestation, dystocia, red bag in horses

cyanobacteria

hepatic hemorrhage leading to acute shock, GI upset, tremors/SLUDGE

fumonisin

moldy corn

nigropallidal encephalomalacia in horses

porcine pulmonary edema in pigs

aflatoxin

aspergillus, moldy grains

liver damage, similar to PAs

black walnut

acute laminitis

oak (Quercus)

renal damage in cattle

bloody diarrhea/melena, tenesmus, abdominal pain

blister beetles

cantharidin, found in alfalfa

oral ulcers, colic, diarrhea, arrhythmias, hematuria/tubular damage

yew

taxine alkaloids

rapid onset vomiting, seizures, ataxia, death

amanita mushrooms

liver/kidneys

dogs>cats

sago palm

cycads

dogs - GI upset, neuro, liver failure

white snakeroot

cyt P450 disrupts cellular energy

acetone breath, weakness, sweaty, tremors

larkspur

delphinium

cattle - sudden death

list of neuro toxic plants

nightshade

hemlock (cicutoxin)

perennial ryegrass

sorghum (cyanide)

yellow star thistle/russian knapweed

locoweed (astragalus, oxytropis, swainsonine)

nightshade

atropine-like (parasympatholytic)

tx = physostigmine

hemlock

cicutoxin

CNS and birth defects

perennial ryegrass

endophyte fungus

cyanide

sorghum, choke cherry, sudan, Johnson grass

cherry red blood, hypoxia, myelomalacia

tx = B12, thiosulfate, methylene blue

GI smells like almond on necropsy

yellow star thistle

nigropallidal encephalomalacia in horses

lips/tongue dystonia, constant chewing

euthanize!

locoweed

astragalus, oxytropis, swainsonine

"crazy weed"

depression, ataxia, circling, abortion

coagulopathy plants

moldy sweet clover

anthrax

Bracken fern

moldy sweet clover

warfarin-like

hemorrhage, not hemolysis

anthrax

reportable! zoonotic! don't cut the carcass!

sudden death, no clotting, no rigor

bracken fern

ptaloquiside + thiaminase

hematuria, hemorrhagic cystitis

polioencephalomalacia in horses

retinal degeneration in sheep

cardiac glycosides

milkweed, gossypol (cottonseed), oleander, foxglove, snakeroot, rhododendron

acute death, arrhythmias

ionophores

monensin - toxic to horses, normal feed additive for cattle

necrosed myocardium, DCM, elevated CK/AST, azotemia, hyperglycemia

plant respiratory toxins

perilla mint, moldy sweet potato (fusarium) - non-collapsing, emphysematous lungs

brassica

brassica

kale, rape, turnips

"fog fever"

tryptophan -> 3MI -> acute interstitial pneumonia from grazing on lush pasture

pyrrolizidine alkaloids

senecio, ragwort, fiddleneck

cause secondary photosensitization - damage the liver, can't convert chlorophyl, lead to hepatic enphalopathy

see megalocytes, bile duct hyperplasia

primary photosensitization plants

St. John's wort, buckwheat, clover

compound in the plant directly causes UV sensitivity

repro toxic plants

veratrum (skunk cabbage, hellbore)

lupine

ponderose pine

veratrum

skunk cabbage, hellbore

day 14 gestation - cyclopia, cleft palate

day 30 - limb/bone shortening

lupine

crooked calf disease, arthrogryposis

ponderosa pine

abortion in last trimester

Toxocara

roundworms

transplacental in dogs, transmammary in cats

zoonotic - visceral larval migrans

baylisascaris (raccoon roundworm)

Ancylostoma

hookworms

anemia, eosinophils, platelets

zoonotic - cutaneous larval migrans

Trichuris

whipworms

mucositis, large bowel diarrhea

Tapeworms

dipylidium, echinococcus, taenia

see proglottids!

from ingesting the flea

zoonotic - hydatid cyst disease

Strongyloides

threadworm

mucoid diarrhea

dx = Baermann

trans = milk/colostrum in foals and pigs

tx in LA = monensin

Coccidia

eimeria - in rabbit poo, self-limiting

isospora

see oocysts in feces

tx = sulfadimethoxine (Albon)

Giardia

zinc sulfate fecal float, IFA

zoonotic!

tx = metro or fenbendazole, ONLY if clinical signs!

Tritrichomonas

cats in catteries/shelters

diarrhea unresponsive to treatment

tx = ronidazole, pradoflox if fails

gnathostoma

stomach worm

vomit the worms!

zoonotic! don't eat undercooked fish

tx = albendazole

small animal lungworms

paragonimus - crayfish, snails

capillaria - looks like trichuris

oslerus

tracheal worm

nodules on bronchoscopy

tx = ivermectin

spirocerca

esophageal worm

osteosarcoma

tx = ivermectin

vomiting worms

physaloptera - beetles/roaches

ollulanis - cats that eat vomit

cuterebra

bot fly (esp cats)

don't squeeze! rupture can cause anaphylaxis

toxoplasma gondii

zoonotic! don't clean litterbox if pregnant

cats definitive

abortion, respiratory, diarrhea, seizures, neuro, stiff/hyperesthesia

tx = clindamycin

neospora

ascending paralysis in ranch dog (eats cow aborted placenta)

abortion - 4-6m (earlier than other pathogens) with autolyzed fetus

tx = TMS + clindamycin

leishmania

sand fly deposits in skin

coonhound from Spain

skin, eyes, mucocutaneous, LNs

trypanosoma

Chaga's

tsetse/kissing bugs poop near bite - P ingests while grooming

myocardial amastigotes, lymphadenopathy, fever, diarrhea

heartworm clinical signs

cough, exercise intolerance, abdominal distension, poor BCS

R ventricle hypertrophy (elevated pressure from narrowed pulmonary arteries)

heartworm in cats

lower worm burden

migrate to ectopic locations

dx = Ab test

tx = corticosteroids

heartworm in dogs

more worms and they survive longer

dx = Ag test (adult females), Knott's (microfilariae)

tx = melarsomine and ivermectin

Wolbachia

symbiotic bacteria of heartworm

tx P with doxy at time of diagnosis!

hesrtworm prevention

year-round monthly macrolide (ivermectin) starting at 8w to kill L3

moxidectin targets microfilaria faster

haemonchus

#1 GI parasite in sheep

anemia, bottle jaw, NO diarrhea

tx = fenbendazole

ostertagia

#1 GI parasite in cows

young cows - more acute, winter and spring

older cows - more chronic, fall and winter

"Moroccan leather" nodules

tx = ivermectin

intestinal parasites in ruminants

cooperia - cow-calf

nematodirus - neonates with acute diarrhea

oesophagostamum - dark watery diarrhea, intussusception

moniezia - ingest orbatid mite

fasciola

liver fluke

snail intermediate host

paramphistomum

rumen fluke

fecal egg count

NOT indicative of parasite load in ruminants (only treat clinical animals)

DOES reflect this in horses (deworm if >200epg)

oxyuris

pinworm

tail rubbing, scotch tape prep

parascaris

roundworm

#1 GI parasite in foals

resp signs, wt loss, diarrhea, impaction

anoplocephala

tapeworm

intussusception

trichostrongylus

stomach worm

chronic CS, weight loss in horses housed near cattle

gasterophilus

equine stomach bot

see yellow eggs on distal limbs, no GI signs

tx = ivermectin in fall-winter

strongylus vulgaris

most deadly GI parasite of horses

migrate through arteries and cause thromboembolism