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15 Cards in this Set
- Front
- Back
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Genera of Trichostrongyles found in the abomasum |
Haemonchus Ostertagia Trichostrongylus (axei) |
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Common name and main hosts of Haemonchus genus |
Barber's pole worm Sheep, cattle, deer, camel |
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Haemonchus species |
H. contortus H. placei |
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Which species occurs in sheep (and rarely cattle) |
H. contortus |
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Which species occurs in cattle (and rarely sheep) |
H. placei |
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Hosts and location of Haemonchus |
Sheep/cattle Abomasum |
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Features of genus Haemonchus |
2-3 cm long (largest in abomasum) Red Tooth in buccal capsule Prominent cervical papillae "Barber's pole" in female Female with large vulval flap Asymmetrical dorsal ray Spicules with barbs |
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Life cycle of Haemonchus |
Direct L3 burrows in between abomasal glands and moults to L4 Re-emerge to lumen |
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Pre patent period of Haemonchus |
21 days |
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Effects on host of Haemonchus |
L4 and adult feed on blood Ingest 0.05ml/worm/day Microcytic, hypochromic anaemia Hypoproteinaemia: bottle jaw Do not cause diarrhoea Reduced exercise tolerance Heavy infections: sudden death Voracious blood sucker |
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Epidemiology of Haemonchus |
High biotic potential (5-10,000 eggs/day) Eggs will not hatch below 10 degrees Larvae not resistant to desiccation |
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Haemonchus in summer rainfall areas |
Increase in spring, maximum in february then decline Overwinter as hypobiotic larvae |
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Haemonchus in winter rainfall areas |
Summers too hot and dry, winter too cool Develop in spring and autumn Problems in spring lambs and autumn lambing ewes |
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Immunity towards Haemonchus |
Self cure when threshold reached Resulting immunity is labile Do not always get strong immunity to reinfection after self-cure |
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Vaccine for Haemonchus |
Available Claim to have 75-95% protection used along with antihelmintics |
