Salient Features of India constitution especially power and functions
Economical Parasite Control
1. D O I N G M O R E W I T H L E S S
Economical Parasite Control
SUSAN SCHOENIAN
Sheep & Goat Specialist
University of Maryland
sschoen@umd.edu
sheepandgoat.com | sheep101.info | wormx.info
2. Gastro-intestinal
parasites (worms)
• Primary health problem of
sheep/goats, especially those
being raised in moist (rain +
humidity) climates or during the
rainy season or wet periods.
• There are many parasites that
infect sheep/goats, but the
barber pole worm (Haemonchus
contortus) is the biggest killer.
• Worms have developed resistance
to the dewormers.
3. How do parasites cost you money?
CLINICAL SUB-CLINICAL NO CLINICAL
4. Clinical
parasitism
• Mortality – death losses
• Production losses
• Weight gain
• Body condition
• Wool production
• Milk yield
• Reduced immunity
• Treatment costs
drugs + labor (monitor + treat) Obvious signs: anemia, bottle jaw, scours, loss of
weight and body condition, anorexia, lethargy
5. Sub-clinical
parasitism
• Production losses
• Weight gain
• Body condition
• Wool production
• Milk yield
• Reduced immunity (disease resistance)
• Treatment costs: drugs + labor (monitor + treat)
Clinical symptoms are not obvious.
6. Healthy
animals
• Unnecessary deworming
• Treatment costs: Drugs + labor (monitor + treatment)
• Prevent animals from developing immunity.
• Contribution to drug resistance due to unnecessary exposure of worms to
dewormers.
No effect on health or productivity
7. Targeted selective
treatment (TST)
on non-treatment
• Only treating those animals which
need dewormed or would benefit
most from treatment; leaving
some animals untreated.
• Reduces number of animals that
are dewormed.
• Reduces amount of dewormer
that is used.
• Increases refugia: worms that
have not been exposed to
dewormer(s); thus, remain
susceptible to future treatment.
• Prolongs effectiveness of
dewormers; delays development
of resistant worms.
19. Dewormer
resistance
• Resistance is the heritable
ability of a worm to survive
a normally effective dose of
dewormer.
• First reports of dewormer
resistance were recorded in
1964.
• Multiple dewormer
resistance is a worldwide
problem on sheep/goat
farms.
• Resistance varies by farm.
20. How to determine
which dewormers
work on your farm
Fecal egg count reduction test
• Compare before and after fecal egg counts (10-14 days)
• Sample 10 or more animals for each drug
• Don’t need to check for all drugs at once.
• Sample same animals each time
• Need high enough fecal egg counts or enough animals
• Can evaluate composite (pooled) samples instead of
individual samples to save time/money.
• < 95% reduction in fecal egg count – resistance present
< 80% significant resistance
< 60% dewormer no longer effective as sole treatment
22. Do-it-yourself
fecal egg counting
Can also use fecal egg counts to monitor
pasture contamination and identify more
resistant (or susceptible animals).
23. Controlling parasites
without drugs or with less
deworming
• Pasture and grazing
management
• Nutrition
• Management
• Genetics
• Impactful deworming
• Confinement
• Common sense
24. Pasture
management to
control
parasitism
• Reduce the length of stay on
pastures
• Reduce stocking rates
• Increase pasture rest periods
• Alternate grazing between small
ruminants and other herbivores:
cattle, horses, ostriches
• Don’t graze pastures too short.
• Avoid hot spots on pastures
(grassed pens, leaky waterers).
• Put lambs/periparturient ewes on
least contaminated pastures.
• Use alternative forages for grazing.
Parasites are primarily a numbers game.
Sheep get infected with they ingest third stage larvae (L3).
25. Nutrition to
control parasites
• Well-fed animals mount a better
immune response to parasites.
• Animals with low body condition are
more susceptible to the effects of
parasites.
• Supplemental nutrition, especially
protein, can reduce the impacts of
parasitism.
• Body condition score your animals
regularly to help you manage the
health and nutrition of your animals.
27. Managing the
periparturient
egg rise
• Deworm ewes in late
pregnancy; targeted selective
treatment recommended.
• Keep ewes in confinement (zero
grazing) during periparturient
period.
• Increase level of protein in late
gestation ration; by-pass protein
is most beneficial.
• Lamb at a time of the year when
parasites are less active.
• Manage ewes according to
number of lambs they have.
29. Use confinement (zero
grazing) to control
parasites, especially in
susceptible animals
• Worms are practically
eliminated in confinement.
• Parasites do not survive well in
straw, dirt, or on slatted floors.
• Grassed pens can be high risk.
• Coccidia can be more of a
problem in confinement, since
it is transmitted in feces.
30. There is usually no need to deworm animals that
are raised in confinement (zero grazing).
31. Get the most impact
when you deworm
• Oral treatments (drenching)
• Combination treatments for
clinically-parasitized animals:
combinations of dewormers with
different modes of action
• Don’t underdose
• Dose based on accurate weight:
dose for heaviest in group
• Calibrate equipment
• Proper drenching technique
• Low stress handling
• Don’t mix products
• Properly store unused dewormer
• Don’t use significantly expired
dewormer
32. Use your head:
anticipate problems
• Consider animals
periparturient ewes, weaners
• Consider weather
warm, moisture
• Consider land
slope, aspect
• Consider pasture
species, ground cover