Bovine- Ostertagia, Haemonchus, Cooperia, Oesophagostomum Flashcards
What is Bovines exposure like?
Bovines defecate eggs on pasture
Bovines consume infective stages on pasture
Level of exposure depends on the production system – more time on pasture, more exposure
What is Bovine Conservative parasite load?
2 epg
What is Bovine Average fecal production?
20 kg/d
What is Bovine Daily production/animal?
40,000 eggs
For a 100-cow herd: 4,000,000 eggs/d
Indoor production has its own issues
200 cows = 10,886 kg (24,000 lbs) of feces and urine per day
When not managed correctly = lots of flies
.
What are the 4 parts to Bovine (beef) production?
Cow-calf
Backgrounding calves/growing
Stocker/finishing
Replacements
What is Cow-calf Bovine (beef) production?
conception to weaning (500-600 lbs; 6-8 mo of age)
on pasture; often extensive
winter housing (of pregnant cows)
What is Backgrounding calves/growing Bovine (beef) production?
weaning to stocker (750-800 lbs)
on pasture or housed
What is Stocker/finishing Bovine (beef) production?
in feedlot until 1100-1250 lbs
90-120 days
18-22 mo of age
What is Replacements Bovine (beef) production?
heifers 12-15 mo
What are the 3 1/2 parts to Bovine (Dairy) production?
Lactating cows
Dry cows
Replacements
Calves
What is Lactating cows (Dairy) production?
indoor or on pasture
What is Dry cows (Dairy) production?
(after lactating/pre-calving)
on pasture or indoor
What is Replacements (Dairy) production?
on pasture or indoor
What is Calves (Dairy) production?
calf hutches; stanchion; pens
indoor or outdoor
Intensive vs. extensive
Low vs. high stocking rate
1st year grazing animal/ 1st year grazer
.
What is Bovine Production?
reproduction/calving interval, time to market, weight gain, work, milk production
What is MRL?
maximum residue limit
What is the Purpose of parasite management?
Maintain the parasites below the economic threshold
Decrease the development of parasite resistance to anthelmintics (anthelmintic resistance)
What is the Economic threshold?
The density of a pest at which a control treatment will provide an economic return
The point where loss is > the cost of treatment
Treatment = drug + handling
Resistance
“When there is a greater frequency of individuals within a population able to tolerate doses of compound than in a normal population of the same species and is heritable”
What is Resistance?
Normal population 1% tolerate Resistance exists if >1% tolerate (Ivermectin) Normal population 5% tolerate Resistance exists if >5% tolerate (Fenbendazole)
An understanding of the parasites is
used to manage them (such as?)
Life cycle Climate Host interaction Nutrition Age Immunological status / reaction
Climate determines when parasites are an issue on pasture
How a parasite survives adverse climatic conditions impacts if the larval stages are an issue for the host
Both of these determine
How the parasite is controlled
When a pasture “clean”
Winter (snow, ice, freezing)
Desert / tropics (long dry periods)
Larvae can survive on pasture OR
In a hypobiotic state in the animal
What is Parasite / host interaction?
Direct and indirect effect
Nutrition
Production status
Immunology
What is Trichostrongyles?
Relate to the small and large strongyles in horses!
Tricho – hair like
So a thinner strongyle!
Life cycles very similar.
What is Ostertagia ostertagi Common name?
brown stomach worm
What is Ostertagia ostertagi Hosts?
cattle
What is Ostertagia ostertagi Identification?
Adults – 1 cm; abomasal surface
Eggs – trichostrongyloid, 85μm
What is Ostertagia ostertagi Site of infection?
abomasum
What is Ostertagia ostertagi Life Cycle?
PPP: 21 d
Arrested L4: up to 6 mo
What is Ostertagia ostertagi Pathogenesis and lesions?
Caused primarily by L3 to immature adult in the gastric glands
Thickened gastric mucosa; raised nodules = “Moroccan leather”
Increased plasma pepsinogen
What is Ostertagia ostertagi Clinical Signs: Type I disease?
Summer Ostertagiosis
In calves during first grazing season
Profuse watery diarrhea
Morbidity high, mortality rare if treatment is instituted in 3 days
What is Ostertagia ostertagi Clinical Signs: Type II disease?
Winter Ostertagiosis
In calves following first grazing season with arrested L4
Profuse watery diarrhea; intermittent
More “bottle jaw”
Clinical disease low, mortality high unless treatment instituted
What is Ostertagia ostertagi Diagnosis?
Clinical signs Season Grazing history Fecal egg counts Type I have epg Type II often negative Culture and identification of L3
What is Ostertagia ostertagi Diagnosis?
Plasma pepsinogen levels elevated
Necropsy examination reveals worms, characteristic mucosa
% adults to larvae high in Type I and low in Type II
What is Ostertagia ostertagi Treatment and Prevention:Type I?
Responds well to anthelmintics
Move cattle to “safe pasture”
What is Ostertagia ostertagi Treatment and Prevention:Type II
Requires anthelmintics effective against arrested L4, larvae and adults
What is Ostertagia ostertagi Treatment and Prevention?
Limiting exposure to infection
Creating “safe pasture”
Exposure is needed to acquire immunity
What is Haemonchus placei Common name?
barber pole worm
What is Haemonchus placei Hosts?
H. placei – cattle
H. contortus – sheep, goats
What is Haemonchus placei Identification?
Adults – 2-3 cm; abomasal surface
Females – “Barber pole”
Eggs – trichostrongyloid, 85μm
What is Haemonchus placei Life cycle?
trichostrongyloid
PPP: 23-28 d when no hypobiosis
What is Haemonchus placei Site(s) of infection?
abomasum
What is Haemonchus placei Clinical signs?
Hyperacute cases calves/lambs die of hemorrhagic gastritis
Acute: anaemia, “bottle jaw”, lethargy
Chronic haemonchosis causes progressive weight loss and weakness
What is Haemonchus placei Diagnosis?
Season Clinical signs History FEC and culture / ID L3 Necropsy
What is Haemonchus placei Treatment and prevention?
Selective anthelmintic treatment
Management
What is Cooperia spp. Hosts?
cattle, sheep and goats
What is Cooperia spp. Identification?
Adults – <9 mm
Eggs – trichostrongyloid, 85μm
What is Cooperia spp. Site(s) of infection?
small intestine
What is Cooperia spp. Life cycle?
trichostrongyloid
PPP: 15-18 d
What is Cooperia spp. Pathogenesis and lesions?
mild
What is Cooperia spp. Clinical signs?
stressed cattle produce watery diarrhea
With Ostertagia most common nematodes of weanling age cattle
What is Cooperia spp. Diagnosis?
fecal egg counts
trichostrongyloid L3
necropsy
What is Cooperia spp. Treatment and prevention?
environment and animal husbandry important
What is Oesophagostomum spp. Common name?
nodular worm;
pimply worm
What is Oesophagostomum spp. Identification?
Adults – 2.5 cm; white
L4 – ≤0.5 cm nodules in large and small intestine wall (can be 2-3 cm dia when repeat infections)
Eggs – trichostrongyloid, 85μm
What is Oesophagostomum spp. Life cycle?
Typical strongyloid
Arrested L4 in small or large intestinal wall
PPP: 45 d or longer
What is Oesophagostomum spp. Site(s) of infection?
Adults in lumen of large intestine
L4 in the wall of small or large intestine
What is Oesophagostomum spp. Clinical signs?
Anorexia
Diarrhea – may be severe
What is Oesophagostomum spp. Diagnosis?
Clinical signs Egg counts -- L3 –not in acute disease since not yet patent –present in chronic disease Necropsy
What is Oesophagostomum spp. Treatment and prevention?
Anthelmintics
Management
Animals do not develop good immunity to infection
