caprine/ovine - parasite lecture

classes

benzimidazoles

macrocyclic lactones

imidazothiazole

tetrahydropyridine

quinolone

benzenesulfonamide

benzimidazoles - examples

fenbendazole

albendazole

benzimidazoles - spectrum

GI nematodes

lungworms

whipworms

cestodes

liver flukes

benzimidazoles MOA

inhibit microtubule synthesis, cellular breakdown

macrocyclic lactones examples

moxidectin

ivermectin

macrocyclic lactones spectrum

GI nematodes

lungworms

mites

lice

macrocyclic lactones MOA

activate glutamate-gated chloride channels, pharyngeal paralysis

starvation

imidazothiazole example

levamisole

imidazothiazole spectrum

GI nematodes

lungworms

imidazothiazole moa

activates nACh receptors, spastic paralysis

tetrahydropyridine example

pyrantel pamoate

tetrahydropyridine spectrum

GI nematodes cestodes

tetrahydropyridine moa

same as imidathiazole - what is it?

quinolone example

praziquantel

quinolone spectrum

liver fluke

cestodes

quinolone moa

damages integument, influx of calcium and spastic paralysis

benzenesulfonamide

benzenesulfonamide exmaple

clorsulon

benzenesulfonamide spectrum

liver flukes

benzenesulfonamide moa

interferes with glycolysis

external parasites - what

lice

mites

ticks

flies

external parasites - phylum

arthropoda

segmented with legs

external parasites - insecta and how many legs

lice

flies

6 legs

external parasites - arachnida and how many legs

mites and ticks

8 legs

lice: clinical syndrome

pediculosis

lice: whats important to know about them

species-specific

lice: life-cycle

on the host

lice: types

sucking

biting

lice: transmission

direct contact and fomites

winter »

lice: c/s

weight loss

rough haircoat

pruritus

patchy alopecia

fleece break in sheep - timing of the disease can be correlated to it

sucking lice: where

head

face

brisket

tail

axillae

distal limb

inguinal region s

sucking lice: goats

ligonathus africanus and stenopsis

sucking lice: sheep

ligonathus ovillus and pedalis

biting lice: goats

bovicola limbata caprae crassipes

biting lice: sheep

bovicola ovis

biting lice: where

neck

withers

tailhead

dorsum

flank

biting lice: signs

skin debris chewing

lice: dx

PE

scotch tape prep

lice: tx

whole herd

shearing

Ultraboss - permethrin

injectable - ivermectin (clinically not worth it)

lice tx weekly why?

hatch weekly (1-2)

for 3 weeks

flies: clinical syndrome

flystrike

fly strike: where

wounds - most common

chronic moisture

fly strike: who

sheep »

fly strike: agent

phormia regina - black blowfly****

lucilia cuprina

fly strike: c/s

fetid, suppurative wounds

areas of moisture accumulations - perineum, topline, maggots

fly strike: dx

c/s

myiasis: tx

clip and clean

topical insecticide - permethrin

mite types

chorioptic

demodectic

sarcoptic

psoroptic

which mites are reportable?

sarcoptic

psoroptic

eradicated from the US

lifecycle of mites

on the host - like lice

chorioptic mange: agent

chorioptes ovis, caprae, bovis

chorioptic mange: most common?

yes

chorioptic mange: c/s

alopecia

pruritus

crusting

distal limns and scrotum

chorioptic mange: dx

skin scrapes - edges

demodectic mange: agents

ovis

caprae

odocoilei

demodectic mange: c/s

non-pruritic nodumes

demodectic mange: locations

face

neck

limbs

dorsum

demodectic mange: dx

deep skin scrape

sarcoptes mange: agent

sarcoptes scabiei var ovis and capra

sarcoptes mange: c/s

alopecia and intense pruritus

sarcoptes mange: where

ears

eyes

neck

scrotum

legs

sarcoptes mange: dx

deep skin scrap

psoroptic mange: agent

goats - cuniculi

sheep: ovis

psoroptic mange: where

sheep - trunk, dorsum and diffuse

goats - ears

psoroptic mange: c/s

intense pruritus

psoroptic mange: dx

skin scrape

mite treatments

ELDU

topical - ivermectin, eprinomectin and permethrin

injectables

nematodes

HOT complex

haemonchus, ostertagia, trichostrongylus spp

protozoa

coccidia

cryptosporidium

haemonchus contortus: key points (6)

hematophagus

live in the abomasum

transmitted while grazing

eggs take 4-6 days to become infectious

warm, humid environments

undergoes hypobiosis in the winter on pasture

haemonchus contortus: c/s

weakness

reduced app

bottle jaw - CLASSIC

pale mms

sudden death

± d+

haemonchus contortus: lifecycle

ingested during grazing

abomasum - matured to adult

produce eggs for 3 weeks (PPP)

eggs are defecated out as L1

L1 need to migrate out through pasture

mature to L3 in pasture - INFECTIVE stage

haemonchus contortus: temperature

77-100

humidity >/= 68

haemonchus contortus: when

spring

two weeks prior to lambing/kidding

dams and offspring increased susceptibility »

haemonchus contortus: control

feeding management

targeted selective tx

combination deworming

rotational grazing

multispecies graxing

select for resistant animals

haemonchus contortus: feeding management

elevated hay feeding

mineral mix - encourage good health

fresh clean water

haemonchus contortus: address hypobiosis and spring rise

clinical animals

larger litter size

age (yearlings or geriatric)

haemonchus contortus: blanket deworming is not recommended why?

dilutes refugia (refugia group of parasites that have not been exposed to the dewormer yet)

increased exposure to dewormer which increases likelihood of resistance

haemonchus contortus: targeted selective

>4

BCS < 3

high fecal egg count >500

weakness, lethargy, bottle jaw and d+

haemonchus contortus: rotational grazing

watm, humid mos

every 4-6 days

mow when they go

rest pasture - 30-60 days

control stocking density

crypto: agent

parvum affects the villous epithelial cells

crypto: when

first 2 weeks

crypto: agent type

protozoon

highly resilient to disinfection

high shedding rate

immediately infectious

low infectious dose ~17 oocysts

crypto: transmission

fecal-oral

crypto: dx

fecal float

PCR

ELISA - antigen

crypto: signs

3 days after infection

2 weeks

crypto: tx

supportive care

coccidia: agent

Eimeria spp

species specific

coccidia: age

4-5 weeks

coccidia: tx

coccidostat and coccidocidals

coccidia: coccidostat

amprolium - sheep

decoquinate - goat (not in lactating females)

sulfonamides

coccidia: coccidiocidals

ionophores

ostertagia ostertagi: location

abomasum

ostertagia ostertagi: what

brown stomach worm

ostertagia ostertagi: pathophys

ingested larvae invade the gastric glands of the abomasum, where they develop into adults, causing hyperplasia and mucosal thickening. The disruption of acid production leads to failure in the digestion and absorption of nutrients, resulting in protein loss (hypoalbuminemia) and systemic metabolic dysfunction.

ostertagia ostertagi: c/s type 1

Diarrhea, weight loss, decreased appetite.

ostertagia ostertagi:c/s type 2

Severe diarrhea, dehydration, submandibular edema, weight loss.

ostertagia ostertagi: dx and findings

• Fecal Egg Counts: High egg counts in Type I Ostertagiasis.

• Plasma Pepsinogen Levels: Elevated in cases of severe abomasal damage.

• Necropsy: Thickened abomasal mucosa with nodular hyperplasia.

ostertagia ostertagi: tx

• Benzimidazoles, Levamisole, Ivermectin: Effective against both adult and arrested larvae.

lungworm: agent

Dictyocaulus viviparus