Bovine Nematodes Flashcards Preview

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Flashcards in Bovine Nematodes Deck (39):
1

Ostertagia ostertagi-Common Name

Brown stomach worm
(Related to horse strongyles)

2

Ostertagia ostertagi-Hosts

Cattle

3

Ostertagia ostertagi-Identification

Adults: 1 cm, slender, reddish-brown
Larvae: microscopic
Eggs: typical trichostrongyloid, oval, up to 85 um, thin shelled, outer surface of shell smooth, contains morula

4

Ostertagia ostertagi-Life Cycle

Direct. PPP = 21 d
L3 infective stage
Eggs released in feces→ devel. to L3 in fecal pat→ L3 migrate to herbage→ ingest L3 while grazing→ exsheaths in rumen→ further devel. in abomasal gland

5

Ostertagia ostertagi-Site of Infection

Abomasum

6

Ostertagia ostertagi-Pathogenesis and Lesions

Caused by L3 to immature adult in the gastric glands
-reduction in functional gastric glands responsible for producing acidic proteolytic gastric juice; reduction in acidity of abomasal fluid
-thickened gastric mucosa; raised nodules called "Moroccan leather"
-Increased plasma pepsinogen

7

Ostertagia ostertagi-Clinical Signs

Type I-Summer Ostertagiosis
-In calves during first grazing season
-Morbidity high, mortality rare if treatment is instituted in 3 days
-Profuse watery diarrhea, persistant and bright green
Type II-Winter Ostertagiosis
-In calves following first grazing season with arrested L4
-Profuse watery diarrhea; intermittent
-More "bottle jaw" (submandibular edema)
-Clinical disease low, mortality high unless treatment instituted

8

Ostertagia ostertagi-Diagnosis

Clinical signs, season, grazing history
Fecal egg counts
-Type I have epg
-Type II often negative
Culture and identification of L3
Elevated plasma pepsinogen levels
Necropsy
% adults to larvae high in Type I and low in Type II

9

Ostertagia ostertagi-Treatment and Prevention

Type I
-Anthelmintics, move cattle to "safe pasture"
Type II
-Anthelmintics effective against arrested L4, larvae and adults
Limit exposure, but exposure will cause immunity

10

Haemonchus placei-Common Name

Barber pole worm, wireworm

11

Haemonchus placei-Hosts

Cattle

12

Haemonchus placei-Identification

Adults: 2-3 cm, white ovaries wind spirally around the blood-filled intestine producing "barber pole" appearance
Eggs: trichostrongyloid, oval, up to 85 um, thin shelled, outer surface of shell smooth

13

Haemonchus placei-Diagnosis

History, clinical signs, fecal worm egg counts, trichostrongyloid L3, necropsy

14

Cooperia spp.-Hosts

Cattle, sheep, goats

15

Cooperia spp.-Identification

Adults: less than 9mm, large bursa, "watch spring" posture
Eggs: trichostrongyloid, oval, up to 85 um, thin shelled, outer surface of shell smooth

16

Cooperia spp.-Life Cycle

Direct. PPP = 15-18d

17

Cooperia spp.-Site of Infection

Small Intestine

18

Cooperia spp.-Pathogenesis and Lesions

Mild pathogens in calves

19

Cooperia spp.-Clinical Signs

Watery diarrhea

20

Cooperia spp.-Diagnosis

Fecal egg counts, trichostrongyloid L3, necropsy

21

Cooperia spp.-Treatment and Prevention

Environment and animal husbandry
Older cows devel. immunity

22

Oesophagostomum spp.-Common Name

Nodular worm, pimply worm
(Related to horse strongyles)

23

Oesophagostomum spp.-Hosts

Cattle, sheep, goats

24

Oesophagostomum spp.-Identification

Adults: 2.5cm, white
L4: small and large intestinal walls, nodules may be 0.5cm
Eggs: strongyloid, oval, up to 85um, thin shell, outer surface of shell smooth

25

Oesophagostomum spp.-Life Cycle

Direct. PPP = 45 d
Eggs in feces hatch→ devel. to L3→ L3 ingested and enter wall of small and large intestine→ devel. to L4 in nodules→ adult emerge

26

Oesophagostomum spp.-Site of Infection

Adults: lumen of large intestine
L4: wall of small or large intestine

27

Oesophagostomum spp.-Pathogenesis and Lesions

Anorexia caused by intestinal discomfort

28

Oesophagostomum spp.-Clinical Signs

Acute: seldom seen, caused by larval stages, impairs absorption, temperature, diarrhea and dehydration
Chronic: due to larval and adults, anorexia, diarrhea, intussusception

29

Oesophagostomum spp.-Diagonsis

Clinical signs, fecal exam for eggs and strongyloid L3, necropsy

30

Oesophagostomum spp.-Treatment and Prevention

Anthelmintics, management, no immunity

31

Dictyocaulus viviparus-Common Name

Lung worm
Disease: Husk, hoose, verminous pneumonia

32

Dictyocaulus viviparus-Hosts

Cattle

33

Dictyocaulus viviparus-Identification

Adults: slender, white nematode, 3-10cm
L1: found in fresh feces, 500um

34

Dictyocaulus viviparus-Life Cycle

Direct. PPP = 24d
Eggs→ hatch to L1 and coughed up and passed in feces→ devel. to L3→ migrate to herbage (or dispersed by fungi)→ ingested by DH→ L3 penetrate intestinal mucosa→ reach lung by lymphatics and blood vessels→ mature to adult in trachea and bronchi

35

Dictyocaulus viviparus-Site of Infection

Trachea and bronchi

36

Dictyocaulus viviparus-Pathogenesis and Lesions

Penetration Phase (d 1-7)-larval migration, no clinical signs
Prepatent Phase (d 8-24)-larvae devel. to adults in lungs, alveolitis and bronchitis
Patent Phase (d 25-60)-presence of adult worms in lungs, bronchitis and pneumonia
Postpatent Phase (d 61-90)-if animal survives recovery starts, relapse may occur, entire lungs are diseased

37

Dictyocaulus viviparus-Clinical Signs

Bouts of coughing at rest, postpatent parasitic bronchitis--dissolution and aspiration of dead or dying worms at end of infection

38

Dictyocaulus viviparus-Diagnosis

Clinical signs, history, endemic area, identification of L1 with Baermann method, necropsy

39

Dictyocaulus viviparus-Treatment and Prevention

Anthelmintics, management, vaccine (Europe)