L14 Ruminant Trichostrongyle abomasum | Parasitology Exam 2

What is the most important parasite of adult cattle in USA

Ostertagia ostertagia (brown stomach worm)

What is the preferred environment for Ostertagia osteragia and predilection site

cool, wet climates

predilection site: abomasum

What is the egg characteristics of Ostertagia ostertagia

egg have dark brown numerous blastomeres 80-40micrometers (indistinguishable to Haemonchus)

What is the PPP of Ostertagia ostertagia

2 wks

What are the seasonal transmission characteristics of Ostertagia in warm temperate climates

• highest transmission in winter-spring

• larvae acquired in late spring become hypobiotic (arrested)

  • (to survive hot summers)

What are the seasonal transmission characteristics of Ostertagia in cool temperate climates

• highest transmission in summer-fall

• larvae acquired in late fall become hypobiotic

  • to survive too cold winter in host

What are the difference in grazing patterns of cattle in warm temperate climates vs cool temperate climates; and how does Ostertagia arrest depending on the climate

• warm temperate climates - freq grazing all-year; L4 stage arrest over summer

• cool temperate climates - seasonal grazing; L4 arrest over winter

What life stage does ostertagia arrest (hypobiosis) and why

early L4 stage arrest for 3-4 mo to avoid adverse environmental conditions

In warm temperate, the L4 stage of Ostertagia will arrest when

over the summertime in the host

In cool temperate, the L4 stage of Ostertagia will arrest when

over wintertime in host

What is the difference between clinical type I disease vs clinical type II disease of Ostertagia ostertagia

• Clinical type I - ingested of large number of L3 stages in summer

• Clinical type 2 - L4 develops and emerges as adult in late winter causing type 2 dz

In summer ostertagiosis, what is the primary lifecycle of Ostertagia ostertagia to develop clinical type I disease

as temp inc in summer, pasture larval contamination inc reaching infective L3 stage

In winter ostertagiosis, what is the primary lifecycle of Ostertagia ostertagia to develop clinical type II disease

as temp dec in winter, L3 becomes arrested at early L4 stage in abomasal mucosal glands

What is the primary pathology of ostertagia ostertagia

disruption of abomasal mucosa by development of larvae leading to gastric gland destruction

What is the post-mortem pathology of ostertagia ostertagia

• abomasum has putrid smell bc of bacterial overgrowth, high pH

• abomasum mucosa has nodules

• abomasum mucosa edematous and hyperemic

What are the Ostertagia clinical feature involving abomasal gastric glands

• larvae develop disrupting abomasal gastric glands

• high pH in abomasum due to replacement of HCL-secreting cells

What is the clinical feature of Ostertagia infection relating to pepsin

pepsin inhibits digestion of protein

What is the clinical feature of Ostertagia relating to albumin

albumin leakage thru abomasal mucosa

What is the tx of Ostertagiosis

ML is drug of choice

What species is infected by Teladorasagia circumincinta (and its predilection site)

sheeps/goats in abomasum

What is the egg characteristics of teladorsagia circumcinta

reddish-brwon w numerous blastomeres (~80-40micrometers)

What is the PPP of Teladorsagia circumcinta

2 wks

What causes loss of weight and appetite in Teladorsagosis dz (caused by T. circumcinta infection)

hyperplastic inflammation of abomasal mucosa (abomasitis)

What causes hypoprotinaemia in Teladorsagosis dz (caused by T. circumcinta infection)

leakage across damaged mucosa

What causes loss of weight and appetite WITH watery diarrhea in Teladorsagosis dz (caused by T. circumcinta infection)

impaired abomasal func associated w alteration in pH

What is the appearance of abomsal mucosa of Teladorsagia infection

morocco leather apperance

What is the tx of teladorsagosis

Benzimidazole + ivermectin DOC

What are the six sustainable control programs of teladorsagosis

1. build up infection in host

2. farming system

3. seasonal appearance

4. pasture contamination

5. TST and refugia management

6. dx tests

What is the host and predilection site of trichostrongylus axei

hosts: cattle, small ruminants, horses, pigs

predilection site:

• abomasum - ruminants

• stomach - horses pig

What is the smallest trichostrongyle

T. axei

What trichostrongyle nematode has unique characteristic of cross-infection in mixed species grazing situation

Trichostrongylus axei

Trichostrongylus axei is not usually a _____ pathogen by itself and is part of the ruminant ____ complex

primary; PGE