Evaluate the ways in which PHYSICAL METHODS can prevent ectoparasites on farms

Question 1

What are ectoparasites?

Answer 1

Diverse group of organisms that live outside the hosts body

Question 2

What are the main group of ectoparasites?

Answer 2

Mainly arthropods - act as micropredators, take short blood meals and pass from individual to individual.

Question 3

What are the main two taxonomic classes when ectoparasites are concerned?

Answer 3

Insecta and Arachnida

Question 4

What parasites does Insecta consist of?

Answer 4

Flies (diptera), bedbugs (hemiptera), lice (phriraptera) and fleas (siphonaptera)

Question 5

What parasites does Arachnida consist of?

Answer 5

Ticks (soft and hard) and mites (demodex sp.)

Question 6

What are three examples of Insecta ectoparasites that cause parasitosis in farm animals?

Answer 6

Stable fly, sheep bot fly and hog sucking lice

Question 7

What is the stable fly and how does it cause problems in horses?

Answer 7

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

Question 8

What is the sheep bot fly and how does it cause problems in sheep?

Answer 8

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.

Question 9

What are hog sucking lice and how do they cause problems in pigs?

Answer 9

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

Question 10

What is an example of Arachnida ectoparasite that causes problems for farm animals?

Answer 10

Sheep tick

Question 11

What is the sheep tick and how does it cause problems in sheep?

Answer 11

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

Question 12

How long do hard ticks take a meal for? Citation

Answer 12

4-7 days it takes to ingest - Bush et al (2001)

Question 13

Why do we need to control ectoparasites on farms?

Answer 13

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

Question 14

What is physical control?

Answer 14

Methods that control ectoparasites using physical agents only - NO CHEMICAL

Question 15

What is successful ectoparasite control based of?

Answer 15

Prevention and the correct diagnosis in order to treat successfully

Question 16

How can feed storage be a way to prevent parasites? Simplicity?

Answer 16

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

Question 17

How can observation of symptoms and behaviours be a a way to prevent parasites?
Simplicity?

Answer 17

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

Question 18

Observing itchy skin can be a way of catching infection early, where are the areas that are usually attacked?

Answer 18

Tail, head, around the ears, scrotum or vulva

Question 19

What is a way to observe lice? Citation

Answer 19

Pressing a warm hand on the animal’s coat - brings lice to the surface where they can be observed
(COWS, 2014)

Question 20

How can PPE be a way of preventing ectoparasites?

Answer 20

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

Question 21

How can nutrition and increased welfare prevent ectoparasites? Simplicity?

Answer 21

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

Question 22

What can be fed to farm animals to decrease the chance of lice and mange?

Answer 22

Kelp as increases coat quality

Question 23

How is education a way to prevent ectoparasites? Simplicity?

Answer 23

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

Question 24

How is contacting DEFRA (Department for Environment, Food and Rural Affairs) a prevention method?

Answer 24

DEFRA will suspend movement between farms, notify all in the area, stop markets and shows (DEFRA, 2012)
SIMPLE

Question 25

How is quarantine/barriers a way to prevent ectoparasites?

SIMPLICITY

Answer 25

Any new sheep on farm should be quarantined straight away and kept away from herd - observe isolated herd for signs - Blow floes - lesions, foul smell and eating less.
Fencing needs to be in place to prevent contact and sufficient enough to prevent nuzzling through fence gaps
Double fencing around the perimeter of the farm - prevent straying sheep or other animals in
Keep grass swards low in grazing pasture - tick questing behaviour
SIMPLE

Question 26

How are masks/preventative objects a way of controlling parasites? SIMPLICITY?

Answer 26

Fly killing equipment around farm - electrocution traps or sticky pads which can give an indication of fly problem risk
Fly masks can reduce stress
Dust baths for poultry - wood ash (Schivera, 2014)
Strict rules for contractors on site - shearers - all objects disinfected (combs), shoes microwaved to kill parasitic organisms (ORGANIC CENTRE WALES, 2003)
SIMPLE

Question 27

How are movement restrictions a way of controlling parasites? SIMPLICITY?

Answer 27

Collaboration with other farms if common grazing occurs - communication so that transmission doesn’t occur from farm to farm
Reduce crowding
Check health status of stock before buying or selling
Group animals together - e.g. younger animals together on better pasture as more susceptible to disease
LESS SIMPLE methods to check health status from sellers may be poor

Question 28

How is good biosecurity a way of controlling parasites?

SIMPLICITY?

Answer 28

Disinfecting vehicles as they come in and out
Disposal and removal of faeces around cattle as much as possible to not attract flies
Hygiene upkept in all areas - regular jet washing
Dispose of dead animals appropriately
SIMPLE

Question 29

How is a health plan a way of controlling parasites?

SIMPLICITY?

Answer 29

Ensure ectoparasitic control is included in the health plan and ask vet what treatments would be best if infection was to occur.
Ensure there is a plan to bring animals indoor immediately if necessary
Animals that are continually susceptible to parasites should be culled or not bred
Breeding for resistance should be implemented
Continual evaluation of the plan, why isn’t it working etc..

Question 30

What is the most simple and effective way to reduce transmission?

Answer 30

Barriers and quarantine - separation from the flock means less chance of mass outbreaks

Question 31

What is the best suggestion for physical control of ectoparasites on farms?

Answer 31

Combining all methods