disease control and goat husbandry

features of healthy sheep

• bright

• ears pricked

• head carriage

• slight smile

• good fleece

• normal flock behviour

sick sheep

Head carriage lower

Drooped ears

Thin

Reduced rumen fill

Diarrhoea

Lameness

Increase respiratory effort

Reluctance to move

Clenched cheek muscles

Drooping eyelids (orbital tightening)

Cud spillage/cheek packing

causes of lameness

• scald and footrot

• contagious ovine digital dermatitis

• others

abortion

Enzootic Abortion in Ewes (EAE) – Chlamydia abortus

• Toxoplasmosis – Toxoplasma gondi

• Campylobacter

• Salmonella

• Listeriosis

causes of internal parasites

• gastro intesitinal nematodes

• coccidiosis

• cryptosporidosis

• liver fluke

effects of worms on lamb

• depressed appetite

• permanent gut damage

• impaired mineral retention

• reduced protein metabolism

approach to gastro intesinal nematodes

• genetics

• avoidance

• management- ewe nutrition and forage type

• effective treatment- quarantine, correct dose, storage

liver fluke

• trematode- fasciola hepatica

• formerly onfined to the wetter western parts of uk

• rnge increasing

• resistance to one clas of flukicide now not uncommon

• can be a major cause of losses in area where it is common

• control involves effective use of flukicides, avoidance of highly contaminated areas, habitat modification to reduce contamination

external parasites cause

• flystrike

• sheep scab

• lice

• ticks

• chorioptic mange

• keds

• midges

sheep scab

• mite psoroptes ovis

• itchy, wool loss, weoght loss, lost production, can be fatal

• increased incidence si cthe end of compulsory orhanophosphae dipping

• more common in areas of higher sheep density esp those with common grazing

• disease incidence incerase in autumn and winter

• avoid buying in sheep

• treatment on arrival 

• isolate for 28 days

• infection often silent in summer

• serological test available

• mites survive days off host

flystrike

• 3 types of fly

• greenbottle most common

• lay eggs in fleece esp damp or soiled

• maggots hatch out and eat through skin

• often fatal unless early intervention

• minimise fly breeding grounds

• minimise fleece soiling

• well timed shearing

• appication of preventative products

clostridial disease

• organisms near ubiuitous

• found in soil

• found in gut in small numbers

• affected animals usually found dead

• prognosis very poor

• outbreaks

• eg pulpy kidney, braxy struck, tetanus, black disease, gas gangrene, black leg

pasteurella disease

• mennheimia haemolutica- septicaemia in young lambs pneumonia in older

• bibersteinia trehalosi- septicaemia in older lamb

• commensals of urt

• stress- outbreak of disease

• some stand alone vaccine some combined with clostridial disease

iceberg disease

• chronic wasting disease

• johnes disease infects sheep, goats, cattle, deer, lagomorphs

• wasting

• faeco oral transmission

• caseous lympahadentis- infects sheep and goats

• abscess of lymph nodes, wasting

• abscess inhalation wound transmission

maedi visna virus

• cross infection

• wasting, respiratory signs, udder induration, prgressing ascending paralysis

• respiratory transmission as well as colostrum

• test and cull, snatch-lambing, keep young flock and avoid housing, accreditation schemes

ovine pulmonary adenocarcinoma

• jaagsiekte sheep retrovirus

• sheep, rare goats

• respiratory transmission

• scan lungs and cull, snatch lambing, avoid housing

scrapie

• transmissible spongiform encelophalopathy

• sheep and goats

• wasting, neurlogical signs

• sheep differ in susceptibility depending on genotype

• notifiable!!

accreditation schemes

• exist for diseases not present in each flock

examples of zoonoses in sheep

• EAE, toxoplasma, salmonella, campylobacter

• orf

• cryptosporidosis, e.coli, salmonella, campylobacter

housing, management and nutrition of goats

• do not like getting wet

• shelter

• regular foot trimming

• over feeding of concentrates can cause lamintis, obesity and in males obstructive urilithathis

goat parasite control

• rarely get flystrike and not sheep scab

• are evolutionary browsers rather than grazers

• all ages susceptible to worm infection

• dose rate of wormer hgher in goats than sheep

• most dairy herds housed all year round

goat vaccination

• respond poorly to multi valent clostridial vaccines

• antibody repsonse is lower and shorter lived than sheep