TV2102 - Parasitology Ruminant Prac

Haemonchus contortus

ABOMASUM You have anaemic, weak and lethargic sheep. There is no weight loss or diarrhoea but some have bottle jaw. The abomasum has dark red-brown fluid and edmatous abomasal fold which focal areas of haemorrhage.

• Found in tropical climates

• Ingestion of L3 with pasture

• Lays 10,000 eggs/day

• PPR when ewes are pregant, shed more eggs

• Use FAMACHA and dipstix test

Trichostrongylus colubriformis

SMALL INTESTINE Your sheep had villous atrophy and erosions of mucosa in the small intestine. They had soft faeces, anemia, anorexia and weight loss.

• Found in a temperate climate

• Ingestion of L3 with pasture

• 100 eggs/day

Ostertagia ostertagi

ABOMASUM In April-May (Autumn) you find 18-month old beef cattle with nodules/coalesced nodules in the abomasum, anorexia, diarrhoea and weight loss. Very few eggs are found in a FEC.

• Ingestion of L3 with pasture

• Hypobiotic larvae, infected in earlier warmer months and reactivated

• Hyperplasia of mucous cells form nodules

• Use pepsinogen and gastrin levels to diagnose due to reduction in gastric acid and alkaline stomach pH meaning no pepsin being converted from pepsinogen

• Confirm diagnosis with larvae culture

Eimeria spp.

SMALL & LARGE INTESTINE You have 2 month old dairy calves that are anaemic, weak with profuse watery diarrhoea, sometimes with blood, tenesmus and rectal prolapse. The perineum and tail are stained with faeces

• Ingestion of sporulated oocysts

• Need to temp, humidity and vegetation state to sporulate

Oesophagostomum spp.

LARGE INTESTINE You see 0.5-1cm nodules in the small and large intestine.

• Ingestion of L3 with pasture

• Cephalic vesicle

• Thin shell egg with many cells

• Pathogenic L4

Chabertia ovina

LARGE INTESTINE You see 0.5-1cm nodules in the small and large intestine.

• Ingestion of L3 with pasture

• Large buccal capsule

• Two small corona radiata with no teeth

• Thin shell egg with many cells

Trichuris spp.

LARGE INTESTINE You see 0.5-1cm nodules in the small and large intestine.

• Ingestion of embryonated egg

• Brown/yellow egg, two polar plugs, one cell inside

Paramphistoma spp. Calicophoron calicophorum

RUMEN/RETICULUM (adults) & ABOMASUM/DUODENUM (immature) Your calves in Victoria have been in a swampy pasture for 4 weeks, they display anorexia, polydipsia, weight loss and fluid, foul-smelling diarrhoea. The duodenum was congested and oedomatous with erosions and petechiae.

• Ingestion of metacercaria with water and grass

• Pathogenic juveniles causes mechanical damage

Cryptosporidium parvum

SMALL INTESTINE You have 2 week old dairy calves with acute diarrhoea and yellowish faeces, anorexia, lethargic ad dehydrated.

• Ingestion of sporulated oocysts (sporulated and infective)

• Brush border of epithelia

• Four sporozoites and no sporocysts

• Need to do acid stain on faecal smear or immunofluorescence to see

Moniezia expansa

SMALL INTESTINE Your lambs have diarrhoea , anaemia and weight loss after 6-8 weeks of being on a pasture used by adult sheep.

• Ingestion of cysticercoid larvae in orbatid mites (IH)

• 2 sets of reproductive organs, 2 genital pores

• Triangular eggs with pyriform apparatus

Moniezia benedeni

SMALL INTESTINE Your lambs have diarrhoea , anaemia and weight loss after 6-8 weeks of being on a pasture used by adult sheep.

• Ingestion of cysticercoid larvae in orbatid mites (IH)

• 2 sets of reproductive organs, 2 genital pores Square eggs with pyriform apparatus

Fasciola hepatica

LIVER Your sheep have weight loss, anaemia, jaundice, reduced appetite, weakness and ascites after 3-4 months on a pasture in a flooded area. They have hyperplastic cholangitis, fibrosis and cirrhosis in the liver.

• Ingestion of metacercaria with water or pasture

• Juveniles burrow through liver parenchyma

• Adults living in bile ducts

• Treat juveniles with triclabendazole

Dictyocaulus viviparus

BRONCHI & TRACHEA Your calves are coughing and show dyspnoea, anorexia and weight loss. You find white mucous and whitish parasites in the bronchi and trachea.

• Ingestion of L3 with pasture

• Mature to L4 and migrate to lungs as mature

• Lay eggs in lungs, cough up and swallowed

• Eggs hatch in intestines and L1 in faeces

• L1 to L3 in pasture

Echinococcus granulosus

LIVER & LUNGS

• Ingestion of eggs shed by dogs (IH)

• Hyatid cysts with brood capsule and invaginated/evaginated protoscolexes are pathogenic

• Laminated and germinal layer

• Egg is striated embryophore with hexacanth embryo within (oncosphere)

• Adult with 3-4 proglottids, scolex with 2 rows of hooks and cause no clinical signs, not pathogenic

• Develop in lung and livers of HUMANS

Babesia bovis

RED BLOOD CELLS You have cows with inappetence, depression, convulsions, paralysis, aggression, ataxia, anemia, haemoglobinuria and jaundice.

• Ingestion of sporozoites from ticks with their saliva

• Clogs capillaries, ishcaemia in brain, neurological signs unlike babesia bigemina

Rhipicephalus australis

ONE HOST TICK Larvae - Babesia bovis Nymph and adults - Babesia bigemina Males - Anaplasma marginale

• Hexagonal basis captuli

• No festoons

• Pale whitish legs

• Wide distance between first legs and gnathostoma

• Coxa with two short spurs

Rhipicephalus sanguineus

THREE HOST TICK

• Hexagonal basis captuli

• Festoons

• Coxa with two long spurs

Haemaphysalis longicornis

THREE HOST TICK

• Rectangular basis captuli

• Dark brown legs

• Festoons

• Palps extend out laterally

Amblyomma triguttatum

THREE HOST TICKS

• Rectangular basis captuli

• Ornate scutum

• Festoons

• Second segment of mouthparts are almost 2x as long as third segment

Bovicola ovis

SHORT WOOL: plunge, shower and cage dip, short wool backline LONG WOOL: handjet and long wool backline

• Head wider than thorac (biting lice)

• Black transverse stripes on abdomen

• Feeds on skin debris, epidermal scales, scurf, suint, bacteria and dried serum

• Does not survive in high temperatures (<45) and rain soaked fleece (6 hours)

• Populations grow very slowly

Linognathus africanus

• Head narrower than thorax (sucking lice)

• 1st pair of legs shorter and thinner than others

• No parategal plates

• Bulging post-antennal margins

Haematopinus eurysternus

• Head narrower than thorax (sucking lice)

• All three pairs of legs are the same size

• Parategal plates

• Rectangular thorax

• Obvious ocular points

Haematobia irritans exigua

Blood pool feeders which cause bleeding under the skin which is painful

• Can transmit Stephanofilaria spp.

• Dung beetles can eat dung to prevent flies from laying eggs

• Large red eyes

• Wings resting in V shape

• Two black stripes on thorax

• Maxillary palps more than half as long as probiscus

Chorioptes bovis

COWS: hindlegs, perineum, udder and base of tail HORSES: hindlegs SHEEP & GOATS: hindlegs and scrotum

• Feed on skin debris

• Must repeat treatments in 2-4 weeks as no chemicals treat eggs, let hatch and treat to kill larvae

Tritrichomonas foetus

• Sexual transmission, use AI to prevent transmission

• Three anterior flagellum

• One posterior flagella

• Causes vaginitis, endometriosis, pyometra and abortion