Evaluate the ways in which PHYSICAL METHODS can prevent ectoparasites on farms Flashcards
What are ectoparasites?
Diverse group of organisms that live outside the hosts body
What are the main group of ectoparasites?
Mainly arthropods - act as micropredators, take short blood meals and pass from individual to individual.
What are the main two taxonomic classes when ectoparasites are concerned?
Insecta and Arachnida
What parasites does Insecta consist of?
Flies (diptera), bedbugs (hemiptera), lice (phriraptera) and fleas (siphonaptera)
What parasites does Arachnida consist of?
Ticks (soft and hard) and mites (demodex sp.)
What are three examples of Insecta ectoparasites that cause parasitosis in farm animals?
Stable fly, sheep bot fly and hog sucking lice
What is the stable fly and how does it cause problems in horses?
Stomoxis calcitrans
Bites continually which causes immense stress and can be a vector for helminth or protozoan infection.
The maggots feed and develop in decaying faeces and feed
Life cycle is average 28 days
What is the sheep bot fly and how does it cause problems in sheep?
Oestrus ovis
Larvae parasitise the nasal ducts in sheep and goats which leads to severe irritation and potentially pneumonia. They possess structural hooks that latch onto the mucosa.
What are hog sucking lice and how do they cause problems in pigs?
Haemotopinus suis
Take several blood meals a day with specialised mouth parts to suck blood. Leads to mass economic losses and anaemia and growth stunts
What is an example of Arachnida ectoparasite that causes problems for farm animals?
Sheep tick
What is the sheep tick and how does it cause problems in sheep?
Ixodes ricinus - Hard tick
Can be a vector for babesiosis which is infection of the red blood cells
Has a 3 year life cycle and 3 different hosts - sheep is one
Can lead to anaemia and open lesions in which flies can feed on
How long do hard ticks take a meal for? Citation
4-7 days it takes to ingest - Bush et al (2001)
Why do we need to control ectoparasites on farms?
Mass loss of production through disease or the stress caused by the parasite, animals wont be reproducing and growth affected - mass economic losses to farmer’s livelihood
Reputation losses and animal welfare has to be questioned
Costs the sheep industry millions per year
What is physical control?
Methods that control ectoparasites using physical agents only - NO CHEMICAL
What is successful ectoparasite control based of?
Prevention and the correct diagnosis in order to treat successfully
How can feed storage be a way to prevent parasites? Simplicity?
Feed should be properly sealed and kept away from excessively warm/damp conditions. Prevent Stable fly larvae developing in feed.
Animals should be kept away from it as could potentially transmit parasites into feed.
Locked away up high to avoid non-farm animals getting into it e.g. foxes, badgers, rodents and birds.
SIMPLE
How can observation of symptoms and behaviours be a a way to prevent parasites?
Simplicity?
Animals should be inspected when in large gatherings - i.e. before entering new winter housing, shearing and trimming - observations of signs of disease
If you catch early can prevent
Observe signs of stress - mark those who seem different to the rest and continually observe.
LESS SIMPLE - Hard to observe whole flocks and with busy life of farm - can’t always catch early
Observing itchy skin can be a way of catching infection early, where are the areas that are usually attacked?
Tail, head, around the ears, scrotum or vulva
What is a way to observe lice? Citation
Pressing a warm hand on the animal’s coat - brings lice to the surface where they can be observed
(COWS, 2014)
How can PPE be a way of preventing ectoparasites?
Equipment should be sterilised continually - disinfect all objects used to perform tasks on herd
Use different equipment for quarantined herds
Wash clothing regularly - scab mites are often transmitted by contaminated shearing clothing
Change clothing before entering other farms, get doubles of clothing.
Boots and overalls should be worn - boots should be washed regularly
Foot dips should be used before entering new zones/ paddocks
Disposable clothing!
SIMPLE - simple way of preventing transmission
How can nutrition and increased welfare prevent ectoparasites? Simplicity?
Healthy diets will ensure increased immunity and growth and reduce stress - less susceptible to disease
Clean environments with minimum faeces.
Should be ensured they receive diet to reach optimum mineral and vit levels - keeps coat shiny and clean
Allow natural behaviours - daylight and scratching
Ensure they’re not wet for long periods of time and dry out efficiently - clip wool from struck to remove soiled wool
LESS SIMPLE - expensive diet, only so much nutrition can do
What can be fed to farm animals to decrease the chance of lice and mange?
Kelp as increases coat quality
How is education a way to prevent ectoparasites? Simplicity?
Leaflets, courses and books about ectoparasitic lifecycles and prevention- gives idea of when to spot signs and symptoms/ seasonality.
Knowing likelihood of the parasites survival on the environment will determine if the herd need to stay away from environment
Also learn correct parasite identification in order to treat successfully
LESS SIMPLE Expensive courses, methods can differ between farmers, time and effort
How is contacting DEFRA (Department for Environment, Food and Rural Affairs) a prevention method?
DEFRA will suspend movement between farms, notify all in the area, stop markets and shows (DEFRA, 2012)
SIMPLE
