Parasite Treatments Flashcards
What is an auto worm bolus?
A bolus that automatically releases anthelmintic every 3 weeks - prevents eggs release in the first place
Ivermectin auto worm boluses release wormer every 5 weeks to include the PPP
How long do auto worm boluses last?
18 weeks
What is a disadvantage of autoworm boluses?
Never develop immunity
What is the best worming strategy?
Targeted worming
Based on faecal egg counts and growth rates
Worm calves with low growth rates and high faecal egg counts
How can you control dictyocaulus viviparus in heifers in their first grazing season?
Huskvax
2 injections, 4 weeks apart, 2 weeks prior to turnout
+/- panacur in July - may prevent immunity
How can you control telodorsagia circumsincta in sheep?
Use a long-acting anthelmintic eg: Cydectin after lambing but before turnout in the ewes
This prevents pasture contamination
Leave singles in refugia - less peri-parturient immune suppression
How can you treat nematodirus battus in lambs?
Any anthelmintic but macrocyclic lactones = resistance
In April to June
What are the 5 groups of anthelmintics?
- Benzamidazoles - White
- Imidathiazoles / tetrahydropyrimidines - yellow
- Macrocyclic lactones
- Amino-acetonitrile (Monapantel) - red
- Spiroindoles (Derquantel and abamectin) - purple
How can you treat nematodirus battus in lambs?
Any anthelmintic but macrocyclic lactones = resistance
In April to June
What are the 5 groups of anthelmintics?
- Benzamidazoles - White (fenbendazole)
- no residual activity
- kills developing larvae and adults - Imidathiazoles / tetrahydropyrimidines - yellow (levamisole)
- no residual activity - Macrocyclic lactones (ivermectin or moxidectin)
- ivermectin - residual activity 2 weeks
- moxidectin - residual activity 3 weeks - Amino-acetonitrile (Monapantel) - red
- Spiroindoles (Derquantel and abamectin) - purple
How should you treat fasciola hepatica?
October - triclabendazole - kills juvenile stages
January/February - closantel - immatures and adults
April/May - Albendazole - removes all adults
What additional flukicidal doses should be given on high risk farms?
2nd dose of triclabendazole in November
Triclabendazole in June when there is winter infection of snails
Describe a suitable quarantine protocol to prevent worms.
Use class 4 (monapantel) or 5 (derquantel) anthelmintics and repeat in 3-6 weeks Triclabendazole to treat fluke
What worming strategy can you use for calves to be turned out in April to prevent PGE?
3 doses of a short acting anthelmintic, 3 weeks apart
Eg: fenbendazole
What worming protocol would you recommend for calves turned out in May to protect against PGE?
2 doses of a short acting wormer, 3 weeks apart
Eg: fenbendazole
What worming strategy can you use for calves to be turned out in April to prevent PGE?
3 doses of a short acting anthelmintic, 3 weeks apart
Eg: fenbendazole
What worming protocol would you recommend for calves turned out in May to protect against PGE?
2 doses of a short acting wormer, 3 weeks apart
Eg: fenbendazole
What flukicidal drugs MUST NOT be used in lactating dry cows? And when can they be used?
Triclabendazole, closantel, nitroxynil
Use in the 60day dry period
What flukicidal drugs can be used in lactating dairy cows?
Albendazole, ricobendazole, oxyclonazide
What is the only wormer with nil milk withhold?
Eprinomectin
What combination products are available?
Levamisole + triclabendazole
Ivermectin + closantel
When should you worm animals using a combination product?
At housing - dairy young stock and beef cattle
At drying off in Autumn - dairy cattle
What can be used to treat psoroptes bovis?
severe scab formation along the back, shoulders and tail head
Permethrin
Resistance to macrocyclic lactones
What flukicidal drugs are there?
Triclabendazole - all stages of fluke
- use at the beginning of the dry period in dairy cows = 48d WP
Closantel - kills late immature fluke (6-8w)
Nitroxynil - adulticide
Albendazole - adulticide (60 WP)
What parasites should you consider in dairy calves being turned out for their first grazing season?
Ostertagia
Cooperia
Dictyocaulus viviparus
Fluke
How can you prevent ostertagiosis using wormers?
Ivermectin used at 3, 8, 13 weeks after turn out
- PPP ostertagia - 3w
- ivermectin residual activity - 2w
- dose at 13w reduces the risk of type 2 disease
(Could use moxidectin with a residual activity of 3w)
How can you prevent ostertagiosis for financially restricted farmers?
Benzamidazoles
- 3 and 6 weeks after turn out to prevent eggs being shed on to the pasture
Risk of type II ostertagiosis with this or protocol - give another dose when the cows are bought in
What is a typical presentation of babesia divergens?
West of the UK
Yearling calves
Diarrhoea, haemoglobinuria, haemolytic anaemia, fever
How can you diagnoses babesia in cattle?
Giemsa stained blood smear - meritzoites
How can you treat bovine babesiosis?
Imidocarb
- very long meat withdrawal - 250 days!!
Need to inform the VMD
Blood transfusions
Expose young stock to infection
Only buy in from endemic areas or don’t buy in young calves (under 12m)
Synthetic pyrethroid pour on
How can you manage neospora caninum?
Identify positive cows - serology
Cull positive cows - expensive
Breed positive cows to beef and sell calves
Dispose of all aborted material quickly and don’t allow dogs to scavenge
Good biosecurity
Don’t allow dogs to poo on feed
How can a farmer control helminths in his adult milking cattle?
Macrocyclic lactone when bought in for housing
- eprinomectin (only one with no milk withdrawal)
- should have developed good immunity
Triclabendazole - at the start of the dry period
(48 day milk withdrawal)
- Albendazole (60h WP), oxyclozamide (72h WP)
Avoid wet pastures in Autumn
Dictyocaulus viviparus - annual boosters of huskvax and turn out 2 weeks later
