Sheep Flashcards
time of year can be indicative for dz dx. what are the main concerns around September/oct –> March
abortion
what time are year is lambing (usually) and when is tupping
tupping - sept/oct for march lambing
as always how can diseases be avoided on farm?
- biosecurity
- reduce dz challenge - hygiene, ventilation, stocking; test and cull policy; drug treatments (ATH and abx)
- improve resistance (vac, good management and selective breeding)
there is strategic and emergency thereapeutics, give an example of each:
- strategic - ATH (fuke, PGE)
- emergency - abx, NSAIds - mastitis
how many sheep are there in the UK
32 M (4% of world sheep pop)
give an example of a hill, upland and lowland breed
hill - swaledale
upland - blue faced Leicester
lowland - texal
desc the basic wrkingso feach type of sheep farm
hill - hardy, 1 lamb
upland - large, fast growing, prolific. cross hill breed to long-wool male = mule
what are EBV
estimated breeding values - heritable traits, breeding index expressed against a herd/national average
NB remember to half the rams potential, when mixed with ewe
give the common EBVs for sheed
- no lambs
- milkiness
- lamb growth in 8wks
- scan weight (21wks)
- carcass conformation
- mature size (ewe kg at 1st mating)
what is a gross margin
output - variable costs (feed, bedding, replacements, vets)
what is a net margin
gross margin - fixed costs (rent, utilities, labour)
What is the average net margin of a UK sheep farm
-£16.51 for a lowland; -£13 for upland/hill
what are the main KPIs
- scanning %
- % lambs reared/ewe
- lamb growth rates
- cull rate and ewe mortality
- ewe:tup ratio
what is the scanning % target
195% lowland; 175% upland/hill
what is the target % lambs reared/ewe
147% and 132%
whats the target DLWG kg/d for lambs
0.35kg/d
whats the ideal ewe:tup
(40:1)
what are the impt components of a flock health plan
- assurance scheme req
- flock KPI and records
- biosec
- nutrition
- para control
- vaccine
- euth policy
- fertility and lambing management
- mastitis and lameness protocols
when are the key times of year to check on sheep flocks
pre-tupping - summer. check fert, lamb growth, para and lameness, BCS
pre-lambing - winter. check scanning data, nutrition, dystocia and colostrum protocols
what could be reaons for low scanning %
- seasonal
- infectious infert (toxo or border dz)
- ewe factors (age, BCS, dz - fluke, lame, Maedi Visna)
- rams (as afor ewes)
- infectious abortion
causes for neonatal mortality
- infections
- starving
- hypothermia
- ZnS turb test (colostrum)
causes of grower mortality
- clostridal
- pasteurellosis
- para
- trace element def
- nutrition
what are the SCOPS principles
- adv on good ATH usage
- dose to heaviest
- good technique
- in refugia pop
what management controls should farmers employ bw july and September
ewe and ram fertility assessment
ID breeding goals
give abortion vacc
how long is sheep gestation
145d (5mths ish)
during pregnancy what measures are undertaken to the ewes
- nematode tx and fluke tx
- clost and past vac
- dagging
- scanning
- ewe nutrition
- foot-rot vacc
name common diseases, which biosecurity can prevent
- enzootic abortion - vac and source only EAE accred sheep
- maedi visna - source accred only
- CLA (caseous lymph adenitis) - blood test and isolate new stock
- CODD or footrot - foot vax, quarantine
- orf - quarantine
sheep scab - quarentne an dtx with MLs or OP dip - worms - dose all new stock
how long should sheep be quarentines
28d
what treatments should you give to quarantines sheep
sheep scab - IVM x 2doses, q7d
ATH - monopantel and triclabendazole
vac - footvax, EAE, clostridial, pasteurella
Footbath
what tx should dogs recieve
tapeworm vac q6wks
keep away from carcasses
how else can biosecurity of a famr be improved
- clean and disinf station and protocols for workers, vehicles and equip
- assess fencing, public footpaths - signs, neighbouring stock
what BCS should ewes be at tupping
hill - 2-3
lowland - 3-3.5
what is the target preg loss
<2%
what is the most common cause of abortion
chlamydia abortus (43%)
then toxo,
then campy,
then salmonella
name some less common causes of ovine abortion
- q fever Yersinia e coli listeria border disease schmallenberg tickborn fever
what actons do you take when you ID a aborted ewe
- isolate
- remove contam material and burn
- take sample: foetus, placenta, blood and vaginal swab
- NB zoonotic risk!
which 2 abortive agents can you vac against
toxo and chylamydia
which path causes enzootic abortion
chlamydia abortus
what are the basics of c. abortus
bact gram -ve cocci good at avoiding immune syst replicates intracellularly (trophoblastic epithelial cells) placentitis - thick and necrotic
what is the route of infection for c. abortus
oral infection from discharges or contaminated abortive material
what is the abortion patern of c. abortus
if 90+d gestation, then might be okay
if <90d gestation, will abort after 90d OR the ewe will be latently infected and abort next pregn
if not preg at time of infection - she will be latent and abort next time
if ewe lambes born to an infected mother will abort at their first lambing
do ewes ever become immune to c abortus
yes - after 1x abortion. few become carriers..
how does a placentitis from c abortus cause abortion
- affects nutritional transport and hormone production so therefore damages lamb
- c abortus also causes inflamation to lambs organs
what are the clinical signs of c abortus
- abortion after 90d
- weak/dying lambs
- sheep aren’t ill
how do you dz c abortus
- late preg abortion
- necrotic placentitis
- ZN staining of placenta, foetus, vag d/c to ID organism
- PCR is possible
how do you tx for c abortus
- isolate affected ewes and stop spread
- give ALL yet to lambs Long acting OTC 20mg/kg, 2 doses q2wks
how do you prevent c abortus
- EAE accredited ewes, closed flock system
- vac !
