National Animal Disease Information Service (NADIS) Parasite...
Transcript of National Animal Disease Information Service (NADIS) Parasite...
National Animal Disease Information Service
(NADIS)
Parasite Forecast
April 2013
About this webinar
• The parasite forecast is published monthly
and written by specialist veterinary surgeons
• Based on detailed Met office data
• Sponsored by Merial Animal Health
• Supported by EBLEX, HCC and QMS
Meteorological Data
Temperature
Rainfall
REGIONS
0 N W Scotland
1 E Scotland
2 N E England
3 E Anglia
4 The Midlands
5 S England
6 S W Scotland
7 N W England
& N Wales
8 S W England
& S Wales
9 N Ireland
Temperature Rainfall Above/below regional averages (1961-1990)
Disease Focus:
Nematodirus
Life cycle
Key facts
Control
Development
to worms in
abomasum
Eggs
passed in
dung
Develop
to L3
larvae
Infective L3
migrate up
grass blades
Grazing
lambs ingest
L3 larvae
Nematodirus:
Life Cycle
~15 days
but
delayed if
cold
10-12 days
Nematodirus: Key Facts
May and June usually see the greatest
amount of disease
Clinical signs include profuse diarrhoea
Disease is mainly caused by worm larvae
Nematodirus: Control
• Avoid grazing lambs on pasture used for
young lambs in the previous year
• If not possible, early lambs may require
drenching before the end of April
• Use BZ (group 1) products
Parasitic
Gastroenteritis (PGE)
Risks
Treatment
PGE: Risk • Overwintered larvae picked up by late
pregnant or lactating ewes
• Egg development will be quicker as temperatures increase through March/April
– Eggs passed by ewes maintains infectivity of the pasture
PGE: Treatment
• Target treatments to
thinner or multiple
bearing ewes
• Leave at least 10% of
the flock un-treated!
Other diseases
Coccidiosis
Chronic liver fluke
Cattle nematodes
Tick-borne fever
Coccidiosis • Significant risk in April
• Adverse weather
conditions cause:
– Poor colostrum
– Poor grass growth
– Extended housing
Chronic Liver Fluke
Cattle Nematodes • Dairy calves and autumn-born suckler calves will need
treatment in 1st season unless on safe grazing – Or ‘dose and move’ at mid-summer
– Lungworm is best controlled using vaccination (‘Huskvac’)
• Worm problems are usually greater in wet summers – but Autumn disease can be seen following a dry summer
Ectoparasites: Ticks • ‘Tick-borne fever’ transmitted by ticks
• Abortion in pregnant ewes
• Secondary infections in young lambs
– This ‘tick pyaemia’ causes abscesses
– Control ticks using pour-on acaricides before lambs go on to contaminated pastures
• Tick pyaemia can
cause:
– Paralysis
– Joint ill
– Abscesses under
the skin
Questions
• Please click on the link below to answer a
short quiz and print your Advanced
Livestock Skills certificate