baaa Flashcards
SH01-22
this is the number of lambs born and surviving until a defined event (e.g. marking or weaning);
optimising this is critical to profitability in any production system
lambing percentage
name 3 factors that can determine lambing percentage
- mating period
- late pregnancy
- lambing
80-90% of lamb deaths occur during this period;
deaths within the first week of birth
perinatal lamb mortality
name 3 muti-factorial reasons for perinatal lamb mortality
- poor ewe nutrition
- dystocia
- poor lamb nutrition
undernutrition of the ewe during mid-pregnancy will cause this
leading to poor oxygen, nutrient and electrolyte transfer & low birth weights
poor placental development
poor nutrition for the ewe in the last 6 weeks of gestation can cause these 2 results
- hypoglycaemic lambs
- poor colostrum production
birth weights of lamb outwith this range are at the highest risk of mortality
3-5.5 kg
how much colostrum do lambs need within the first 4h of life?
50 mL/kg bodyweight
name 7 maternal factors contributing to lamb starvation
- genotype
- inexperience
- poor nutrition
- dystocia
- concurrent disease
- mastitis
- multiple lambs
name 6 lamb factors contributing to starvation
- genotype
- multiple litter mates
- birth stress/trauma
- prenatal malnutrition
- hypothermia
- infectious disease
name 4 management practices to ensure adequate nutrition to minimise perinatal lamb losses
- ultrasound data
- body condition scoring
- ration analysis
- metabolic profiles
name 4 management practices to avoid dystocia to minimise perinatal lamb losses
- ewe and ram selection
- use of keel marks and scanning data
- feed management
- good stockmanship
what percent of lamb growth occurs in the last 6 weeks of pregnancy?
75%
name the type of forage
higher energy, good management during storage, problems with listeriosis
grass silage
name the type of forage
quality variable, allow for high wastage rate when feeding straw, get an analysis done
hay and straw
how much trough space per ewe is required if restricted access?
18 in (45cm)
how much water do ewes in late pregnancy require daily?
5-10L
name 2 ways to help increase intakes of poor quality silage in sheep
- put molasses on top of forage
- add SBP or draff to ration
what is often the main limiting factor of colostrum production in sheep
protein
when should body condition scoring be done on pregnant ewes
4-6 weeks before lambing
when should blood sampling of pregnant ewes be done to see what they think of their diet?
3-4 weeks befpre the start of lambing
(at least 5 ewes in each group)
name the 4 things pregnant ewes should be grouped according to
- lambing date
- condition score
- scan results
- age
name the 5 metabolites that should be analysed in blood samples from pregnant ewes to assess nutrition
- BHB
- urea-N
- albumin
- magnesium
- phosphate
what is the target beta-hydroxybutyrate threshold for ewes not scanned
0.8 mmol/L
what is the target beta-hydroxybutyrate threshold for ewes if scanned and fed according to lamb number
1.0 mmol/L
what is the UK target for neonatal disease in lambs
< 7%
name the neonatal lamb disease
seen in lambs 1-3d old;
lethargic, excess salivation and distension of the abdomen;
unwilling to suckle;
caused by E. coli, acquired from environment
watery mouth
name the 5 parts of treatment for watery mouth in lambs
- Flunixin or meloxicam IV
- oral electrolytes
- IV fluids
- soapy enemas
- systemic abx
name the neonatal lamb disease
caused by Clostridium perfringens type B;
spradic cases;
lack of colostral Ab intake;
initially lambs up to 1 wk old, can get in older lambs too;
clinical signs: sudden death, lethargy, tenesmus, vocalisation
lamb dysentery
what sign of lamb dysentery will be seen on PM
haemorrhagic enteritis
name the cause of neonatal lamb enteritis
seen in lamb less than 4d old (rel. uncommon);
K99 adherence pili facilitates attachment to the intestinal mucosa;
toxin produced which interferes with water and electrolyte transport leading to severe watery, brown diarrhoea
enterotoxigenic E. coli
name 4 bacteraemias seen in neonatal lambs
- joint ill (polyarthritis)
- navel ill (omphalophlebitis)
- meningitis
- endocarditis
name the neonatal lamb disease
can be seen in lambs as young as 5d old;
sudden onset lameness;
pain, heat and swelling of several joints;
poor suckling and ill-thrift
joint ill
name 3 PM signs of joint ill in neonatal lambs
- pus in joints
- thickened synovial membranes
- erosion of the articular surfaces
name the neonatal lamb disease
rel. common in young lambs;
more common in male lambs;
results from bacteraemia or infection of the umbilical vessels and urachus from a dirty environment;
can remained localised or spread leading to peritonitis, liver abscesses
navel ill
how to prevent navel ill in neonatal lambs?
dip navel in strong iodine soon after birth
name the neonatal lamb disease
navel infection with Fusobacterium necrophorum;
leads to white spots (abscesses) on the liver;
can spread to lungs and joints
hepatic necrobacillosis
name the neonatal lamb disease
typically affects lambs 2-4 wks old;
lack of suckle reflex, weak, congestion of the sclera, opistotonus
meningitis
name the neonatal lamb disease
most commonly seen in lambs 1-4mo old;
clinical signs will vary depending on location of the abscess;
can be treated with long course of penicillin
spinal abscess
name the neonatal lamb disease
can result in still births or weak lambs;
reluctant to feed;
sudden onset semi-paralysis;
typically die from respiratory failure, starvation or heart failure;
vit E and selenium deficiencies
congenital white muscle disease
name the neonatal lamb disease
sporadically seen in lambs 2-4wks old or 2-4mo old;
aetiology unknown;
lambs depressed, wont suck but appear thirsty;
empty abdomen, normal rectal temp;
soft faeces with perineal staining;
blood urea and creatinine parameters raised
nephrosis
what is ill thrift?
low body condition
what type of blood panel should be avoided in farm practice because it is an unnecessary test and cost?
biochemistry
name the 5 main values in blood to use for screening tests in farm practice
- total protein
- albumin
- globulin
- GGT
- GLDH
what is the organism that causes Johne’s Disease in sheep?
Mycobacterium avium ssp. paratuberculosis (MAP)
name 2 clinical signs of Johne’s disease in sheep
- condition loss
- bottle jaw in late stages
name the cause of ill thrift in sheep
sporadic disease usually in older sheep;
may present like Johne’s disease;
usually a distinct mass sometimes with secondary spread;
may be assoc. with eating bracken
intestinal adenocarcinoma
name the cause of ill thrift in sheep
contageous lung tumour caused by Jaagsiekte betaretrovirus (JSRV);
tumour of the type II pneumocyte cells of the lungs;
‘wheelbarrow test’, clear fluid leaking from nose
ovine pulmonary adenomatosis
name 3 effects of ovine pulmonary adenomatosis (tumour of the type II pneumocyte cells of the lung)
- loss of alveoli structure
- excess fluid production
- consolidation of lung tissue
how can ovine pulonary adenomatosis be diagnosed?
ultrasound
(serology and nasal swab PCR not useful)
what is the most important way to control ovine pulmonary adenomatosis
group sheep by age
name the cause of ill thrift in sheep
cases pneumonia, encephalitis, paralysis, mastitis and wasting in sheep;
closely related to Caprine Arthritis and Encephalitis lentivirus (CAE) in goats;
long incubation period, spread through inhalation;
sheep are infected for life
Maedi visna
name the pathogen causing Maedi Visna in sheep
Visna Maedi lentivirus
what is the treatment/vaccination for maedi visna in sheep?
none available
what is the most used test for diagnosing maedi visna in sheep?
serology - antibody ELISA
name the cause of ill thrift in sheep
contagious skin disease caused by Corynebacterium pseudotuberculosis;
spread through direct contact or fomites;
survices for around 2mo in evironment;
thick abscesses in the lymph nodes
caseous lymphadenitis (CLA)
name the 3 forms of caseous lymphadenitis in sheep
- superficial form
- visceral form
name the cause of ill thrift in sheep
notifiable neurological disease caused by prion protein (transmissible spongiform encephalopathy);
classical and atypical forms;
not thought to be zoonotic;
long incubation period;
pruritis/wool loss, excitability, ear droop, tremors, odd gait
scrapie
what scheme must sheep flocks with confirmed cases of scrapie join?
Compulsory Scrapie Flock Scheme (CSFS)
this is defined as a death that occurs since the last inspection;
often multiple animals;
can almost guarantee those those that die will be the ‘best’ in the group
sudden death
name the 3 main causes of sudden death in sheep
- Clostridial disease
- Redgut
- Systemic pasteurellosis
name the cause of sudden death in sheep
anaerobic, spore forming, toxin producing bacteria;
toxin production follows opportunistic rapid multiplication in the host (botulism is the exception);
control by managing risk factors and vaccination
Clostridial disease
name the Clostridial disease of sheep
a common, peracute and usually fatal disease of sheep - can affect any age;
caused by C. perfringens type D (epsilon toxin) and oedema in multiple tissues;
typically associated with a change in diet
pulpy kidney
name 4 clinical signs of pulpy kidney in sheep
- sudden death
- hyperaesthesia
- ataxia
- convulsions
how to definitively diagnose pulpy kidney at PM of a sheep
demonstration of epsilon toxin on ELISA
(in intestinal contents)
name the Clostridial disease of sheep
rare, peracute disease of adult sheep;
C. perfringens type C;
enteritis, peritonitis, sudden death;
Hx of dietary change in unvaccinated sheep
struck
how to definitively diagnose Struck during PM of a sheep
demonstration of Beta toxin by ELISA
(on intestinal contents or peritoneal fluid)
name the Clostridial disease of sheep
Clostridium sordelii;
sudden death of sheep, can be vaccinated or not;
typically seen in creep-fed lambs 3-10wks old;
clinically seen as bloated depressed lambs
Abomasitis
what is the vaccination for Abomasitis in sheep
Covexin 10
name the Clostridial disease of sheep
rare disease of hoggs (lambs between 9-18mo);
causes severe abomasitis;
C. septicum;
associate with ingestion of frosted food
Braxy
name 2 ways to diagnose blackleg in sheep
- demonstration of bacteria on smears
- fluorescent Ab tests on smears
name the Clostridial disease of sheep
C. chauvoei;
spores survive in soil for years;
typically seen following docking, castration, shearing, dirty needs, poor lambing hygiene, wintering on root crops;
causes cellulitis, necrotising myositis, toxaemia and gas production
Blackleg
name the Clostridial disease of sheep
fatal peracute disease affecting sheep of all ages;
alpha and beta toxins of C. novyi type B;
instigated by migrating liver fluke larvae
black disease
how to definitively diagnose black disease in sheep
demonstration of bacteria in smears of cut liver tissue
name the Clostridial disease of sheep
disease of sheep of any age;
massive facial swelling with pitting oedema and gas production;
most commonly seen in ram lambs;
C. septicm, C.novyi, C. chauvoei;
can respond to treatment if seen early
malignant oedema
name the Clostridial disease of sheep
fatal, paralysing disease of all species;
neurotoxin;
ubiquitous organism in the soil;
spores enter deep wounds;
clinically causes sustained spasm and rigitidy of voluntary muscles;
unable to swallow or eructate
tetanus
(C. tetani neurotoxin)
name 3 treatments for tetanus
- tetanus antitoxin
- antibiotics
- analgesia
name the Clostridial disease of sheep
rare disease which can affect all species;
flaccid paralysis and incoordination, pelvic limbs initially;
leads to recumbency and death;
no specific PM findings - diagnosis based on Hx and clinical signs
Botulism
(C. botulinum toxin - type B, C, and D)
when should the annual booster of Clostridium vaccine be given?
6 weeks before lambing
name the cause of sudden death in sheep
sporadic condition;
intestinal torsion in weaned lambs or adult sheep;
sudden death due to endotoxaemia and circulatory failure;
associated with legumes or lush forage
Redgut
name 2 ways to prevent redgut in sheep
- gradually introduce onto lush pastures
- provide good quality fibre
what is the gestation period for sheep?
142-152 days
what is the oestrus cycle length for sheep?
16-17 days
what is the normal length of the luteal phase for sheep
13-14 days
what is the normal length of follicular phase in sheep?
3-4 days
what should the scrotal measurement for a ram lamb be?
32 cm
what should the scrotal measurement for a shearling ram be?
36 cm
what percent of adult body weight must a ewe be at tupping?
70%
low levels of this nutrient in the ewe can result in embryonic loss in first 3-4 weeks
selenium
what nutritional profiling can be done to look at long-term selenium levels in ewes
GSHP-x
name 3 nutritional profiling that should be done for ewes to prepare for tupping
- GSHP-x
- iodine
- vitamin B12
what is the ram to ewe ratio for adult rams
1:40-60
what is the ram to ewe ratio for ram lambs
1:30
what months are breeding season for sheep?
September - December
name the method of manipulating breeding in sheep
can advance the breeding season by 2 wks;
helps to synchronise the ewes;
intro a vasectomised ram which induces ovulation, remove after 7d
ram or teaser effect
name the method of manipulating breeding in sheep
synchronises ewes;
canadvance breeding season by 4-6 weeks, include PMSG;
insert at day 0, remove at day 12-14 +/- PMSG injection, intoduce fertile tup 36-40h later (1 ram per 10 ewes)
progestagen sponges
what injection must be given at removal of the progestagen sponge for AI in sheep
PMSG
name the method of manipulating breeding in sheep
launched in UK this year;
works same way as progestagen sponges;
claims of less irritation/vaginitis;
leave for 12 days, PMSG at removal, oestrus 1-2d later
CIDR ovis
name the method of manipulating breeding in sheep
naturally increases with decr. daylength;
implant mimics this and can advance the breeding season by 2mo;
Regulin ear implant
melatonin implants
how many days after melatonin implant should the rams be introduced
42 days
how to perform AI in sheep?
laparascopic
what conception rates can you get with laparascopic AI in sheep?
depends on perator skill and semen quality
65-70%
what is the optimal time during gestation to identify foetal numbers in sheep
60-90 days gestation
what can be used to terminate pregnancy in sheep?
PGF2⍺
name 2 drugs that can be used to induce parturition in sheep
- Corticosteroids
- Dexamethasone
name 3 causes of high barren rates in sheep
- ewes not cycling
- fertilisation failure
- failure to conceive or maintain early pregnancy
investigation is warranted if the ewe barren rate is higher than what percent?
5%
name 4 common causes of ram infertility
- epididymitis
- inguinal hernia
- testicular degeneration
- scrotal mange
name the common cause of ram infertility
common cause of permanent infertility,
often no clinical signs;
typically lesions are found in the tail of the epididymis;
testicular atrophy;
organisms enter the repro tract through the prepuce from the environment
epididymitis
name the 3 main agents causing epididymitis in rams in the UK
- Actinobacillus semnis
- Haemophilus somnus
- Histophilus ovis
name the significant cause of epididymitis in rams overseas
Brucella ovis
name the common cause of ram infertility
large swelling of the scrotum;
intestinal contents coming through the inguinal ring;
testicular atrophy;
usually unilateral;
diagnose by u/s;
permanently unsound
inguinal hernia
name the common cause of ram infertility
bilateral small testes;
poor semen quality;
specific cause often unknown;
various factors: systemic disease, environmental temperature, inflammation, extreme fatness
testicular degeneration
name the common cause of ram infertility
widespread in the UK;
causes pruritic lesions on the pull, coronary band, accessory digits and scrotum;
handling of scrotum often results in a nibbling reflex;
raises temp of the scrotum which impacts spermatogenesis
scrotal mang
Chorioptes bovis
name the common cause of ram infertility
often rsults from shearing wounds;
if caught and treated early fertility can be preserved;
differentiate from inguinal hernia and epididymitis by position of swelling
scrotal abscess
what is the target rate for abortion in sheep?
< 2%
name 6 common causes of abortion in sheep
- Chlamydophila abortus
- Toxoplasma gondii
- Salmonella spp.
- Campylobacter fetus fetus (intestinalis)
- Border disease
- Listeriosis
name the infectious cause of abortion
most common diagnosed cause;
late abortion, stillborn or weak lambs;
ZOONOSIS;
Chlamydophila abortus
Enzootic Abortion of the Ewe (EAE)
what stain should be used to diagnose Enzootic Abortion of the Ewe (EAE)
ZN stain
(clusters of red bodies against blue background)
what is the outcome if infection of Enzootic Abortion of the Ewe (EAE) occurs during first half of the pregnancy (>6wks off due date)
abort during last 3 wks of pregnancy
what should all ewes be treated with during an Enzootic Abortion of the Ewe (EAE) outbreak
long acting oxytetracycline
(2-4wks before lambing)
name the infectious cause of abortion in sheep
lifecycle involving rodents and cats;
barren ewes if infection in early pregnancy;
abortions/stillbirths late pregnancy;
normal if infected after 120d or when empty;
ZOONOTIC
Toxoplasmosis
(Toxoplasma gondii)
what placental change is associated with Toxoplasmosis in sheep
necrotic cotyledons with white spots
(like strawberries)
name the infectious cause of abortion in sheep
5% of diagnosed abortions;
gram neg bacteria;
abortion in final 6 weeks of pregnancy;
sporadic outbreaks in UK flocks, very common in NZ;
ZOONOTIC
Campylobacterosis
(C. fetus fetus)
name 3 ways to diagnose Campylobacteriosis in sheep
- gross signs
- gram or ZN stained smears of foetal stomach contents
- bacterial culture of foetal stomach contents
name the infectious cause of abortion in sheep
ZOONOTIC;
gram neg aerobic bacteria;
poor hygiene;
sporadic;
enteric or generalised ill health in ewes;
septicaemia
Salmonellosis
name the strain of Salmonella causing abortion in sheep
common in southeast scotland;
sheep and cattle - often no signs of impending abortion;
often rotten, autolysed lambs;
some ewes become sick with metritis afterwards
Salmonella enterica serotype Montevideo
name the 2 strains of Salmonella causing abortion in sheep
sick and pyrexic ewes: may die of septicaemia before they abort;
profuse diarrhoea;
stinking lambings with emphysematous lambs
- S. typhimurium
- S. dublin
what agar should be used for bacterial culture to diagnose Salmonellosis as cause of abortion in sheep
MacConkey agar
name the infectious cause of abortion in sheep
related to BVD in cattle;
viraemia and necrotising placentitis - outcome depends on the foetal immunocompetence;
barren ewes, abortions, weak lambs (‘hairy shaker’ lambs, poor doing lambs)
Border disease
name the time of Border Disease infection based on outcome
foetal death and resorption - barren ewes;
still births;
surviving lambs: PI animals, ‘hairy shakers’, ill thrifty
< day 60
name the time of Border Disease infection based on outcome
some normal lambs;
some lambs with major CNS abnormalities
day 60-85
name the time of Border Disease infection based on outcome
late abortions;
normal survivors
after day 85
name the infectious cause of abortion in sheep
uncommon;
usually associated with feeding poor quality silage with pH >5;
losses usually third trimester;
foetuses very autolysed, examine liver and brain for micro-abscesses
Listeriosis
name the 5 things to assess on a neuro exam from a distance
- demeanour
- posture
- awareness
- symmetry
- gait
name 4 things to assess on the head during a neuro exam
- assess mentation
- head carriage
- facial symmetry
- cranial nerves
name 3 things to assess at the neck during a neuro exam
- range of movement
- pain
- extend examination along the spine
what reflexes should be assessed while the animal is standing
proprioceptive reflexes
what 4 reflexes should be assessed with the animal in lateral recumbency
- Patellar reflex
- extensor carpi radialis reflex
- withdrawal reflex
- cutaneous trunci
where would the spinal lesion be if the patellar reflex is affected
L4-L6
where would the spinal lesion be if the extensor carpi radialis reflex is affected
C7-T2
where should CSF be collected for diagnostic tests?
lumbosacral region
(between L6 and S2)
name the location of the brain lesion based on the common signs
- depression
- apistotonus
- circling
- hyperaesthesia
- head pressing
- visual deficits
cerebral lesions
name the common presentation of cerebral lesions
seen in weaned lambs, less commonly in growing cattle;
occassionally in adult sheep;
recent diet change ~2wks ago;
possibly recent anthelmintic treatment;
isolated from group, aimless wandering, blindness, star gazing stance, hyperaesthetic;
dosomedial strabismus and horizontal nystagmus
Polioencephalomalacia (PEM)
aka
Cerebral Cortical Necrosis (CCN)
overgrowth of bacteria producing this product in the rumen precipitates Cerebral Cortical Necrosis (CCN);
destroys the vitamin essential to glucose metabolism
thiaminase
(destroys thiamine - vitamin B1)
name 2 signs of Cerebral Cortical Necrosis (CCN) seen on post mortem
- necrosis of grey matter of brain
- cut surface fluoresces under Wood’s Lamp
what is the treatment for Cerebral Cortical Necrosis (CCN) ?
vitamin B1 (thiamine)
(10 mg/kg, IV initially, followed by IM injections)
name the neuro disease
rare in ruminants;
affects animals 3-6 months old;
progressive clinical disease;
blindness and proprioceptive deficits on the contralateral side (PLR normal);
depression, sometimes circling but more likely standing in a corner
brain abscesses
name the common brainstem disease
affects sheep, cattle, goats, & pigs;
typically associated with big bale silage of poor quality;
can affect up to 10% of group;
typically seen in winter/spring;
absence of blink response, unilaterally;
progresses to death within 10-14d
Listeria
(Listeria monocytogenes)
localise the lesion based on the common clinical signs:
- difficulty eating
- nystagmus
- ptosis
- ear drooping
- drooling
- head tilt
- loss of menace
brainstem lesion
what lesions does Listeria cause in the brain stem?
microabscesses
how does Listeria bacteria reach the brainstem?
along Trigeminal nerve through abrasions in mouth
name 4 differential diagnoses of Listeria in cattle
- BSE
- CCN
- Lead poisoning
- Rabies (where present)
name 2 differential diagnoses for Listeria in sheep
- brain abscess
- nephrosis
what is the drug of choice for treating Listeria?
penicillin
(high dose)
what is the success rate of aggressive treatment (penicillin) for Listeria
30-50%
name 4 ways to prevent Listeria
- avoid mouldy silage
- remove stale feed from feeders
- feed hay to gimmers
- treat silage to incr pH
aside from encephalitis, name 3 other things Listeria monocytogenes can cause ;
unusual for multiple forms to occur at same time
- abortion
- silage eye (anterior uveitis)
- neonatal septicaemia (visceral Listeriosis)
name 3 typical clinical signs of vestibular lesions
- head tilt (ipsilateral)
- circling
- nystagmus
early treatment with what drug can result in good responses in animals with vestibular disease
penicillin
name 4 common clinical signs of cerebellar lesions
- wide-based stance
- ataxia
- hypermetria
- intention tremors
name the neuro disease
Transmissible Spongiform Encephalopathy (TSE);
exact causative agent still unknown, referred to as prions;
progressive disease, initially ill-thrift;
commonly seen in 3-5 y/o;
no test in live animal for diagnosis, clinical signs often non-specific
Scrapie
localise the spinal lesion
all 4 limbs affected - ataxia and weakness;
exaggerated reflexes in fore and hind limbs
cervical spine (C1-C6)
localise the spinal lesion
ataxia and weakness more severe in forelimbs;
scuffing/abnormal wear of toes in forelimbs
brachial region (C6-T2)
localise the spinal lesion
normal thoracic limb function;
weakness and ataxia of hindlimbs;
exaggerated pelvic limb reflexes;
panniculus is absent caudal to the lesion
T2-L3
localise the spinal lesion
flaccid paralysis of hindlimbs
L4-S2
localise the spinal lesion
bladder distension and loss of anal tone
S1-S3
will lesions compressing the spinal cord cause increased or decreased CSF protein concentrations
increased
name the neuro disease
sporozoan parasite with ruminant intermediate hosts, carnivores are the definitive host;
commonly found in heart and skeletal muscle of sheep in UK;
6-12mo old sheep;
neuro signs include tremors, recumbency, nibbling, fore or hindlimb paralysis;
can only be confirmed histologically
Sarcocystitis
name the neuro disease
can affect the lateral ventricles of the brain or the thoracolumbar spinal cord;
slow onset head tilt and circling towards the affected side;
hypermetria and hindlimb ataxia;
euthanase on welfare grounds
visna
(manifestation of Maedi Visna Virus)
name the neuro disease
aka Elso heel;
occurs in calves from birth to 12mo;
calves initially seen with excessively straight hocks;
gastrocnemius and superficial digital flexor tendon have excessive tone;
commonly bilateral;
unknown aetiology
spastic paresis
name the 2 treatment options for spastic paresis in calves
- tibial neurectomy
- Gastrocnemius tenotomy
name 4 common ectoparasites causing skin disease in sheep
- sheep scap (Psoroptes ovis)
- Blowfly strike (myiasis)
- Lice (bovicola ovis & Linognathus spp)
- ticks
name 5 common non-parasitic causes of skin disease in sheep
- orf
- caseous lymphadenitis
- dermatophilosis
- photosensitisation
- ringworm
name the skin disease in sheep
host-specific mite, highly contagious;
welfare problem and economic losses;
mite lives in environment for up to 17 days;
up to 100% morbidity;
outbreaks usually in winter/spring;
immediate and delayed hypersensitivity reactions
Sheep scap
(Psoroptes ovis)
name 4 clinical signs of sheep scab
- intense pruritis
- wool loss
- scab formation
- death
name 2 ways to diagnose sheep scab
- skin scrapes
- ELISA antibody test (Psoo2)
name 2 treatments for sheep scab
- plunge dipping (diazinon - organophosphate)
- systemic endectocide injections (macrocytic lactones)
how long must sheep be immersed in organophosphate dip for it to be effective against sheep scab
1 min
name 3 advantages of organophosphate dips as treatment for sheep scab
- kills mites w/in 24h
- washing effect removes dead mites
- residual protection for several weeks
name 4 disadvantages of organophosphate dips as treatment for sheep scab
- human and environmental hazards
- operator requires certificate of competence
- stressful procedure for sheep
- long meat withdrawal periods (70d)
name 3 advantages of macrocytic lactone injections as treatment for sheep scab
- less complex to administer
- safer for operator, sheep and environment
- residual protection for several weeks (Cydectin LA)
name 3 disadvantages of macrocytic lactone injections as treatment for sheep scab
- pruritis may persist for up to 30d
- takes time to kill mites
- promotes anthelmintic resistance
name the skin disease in sheep
occurs during summer months (may-sept);
parasite attracted to soiled areas of fleece;
lay eggs which hatch w/in 12h;
larvae penetrate skin and secrete enzymes causing irritation, secondary bacterial infection and eventually toxaemia;
discoloured grey, moist wool and offensive smell;
wool loss and dermatitis
Blowfly strike (myiasis)
name 3 ways to control Blowfly strike in sheep
- plung dipping (OP dips) for 3wks after shearing
- shower dipping & hand/automatic jetting
- pour ons (synthetic pyrethroids, insect growth regulators)
name the species of chewing lice affecting sheep
Bovicola ovis
name the 2 (less common) species of sucking lice affecting sheep
- Linognathus ovillus (face)
- Linognathus pedalis (limbs)
how long is the lifecycle of chewing lice (Bovicola ovis) under ideal conditions?
30 days
name the skin disease in sheep
parasite found along dorsum and flanks feeding on skin debris;
cause irritation and intense pruritis;
rubbing/biting shoulders, flanks, back;
broken wool, matting and discolouration;
entire life cycle spent on host, requires close contact for transmission
chewing lice (Bovicola ovis)
name 3 treatments for chewing lice (Bovicola ovis) in sheep
- shearing
- plunge dipping (OP)
- synthetic pour-ons
(systemic endectocides NOT effective)
name 5 tick-borne diseases affecting sheep
- tick-borne fever
- tick pyaemia
- louping-ill
- Q fever
- Babesiosis
name the skin disease in sheep
parapox virus;
ZOONOTIC;
immunity to infection short-lived;
NO colostral transfer of immunity;
proliferatice lesions on lips and nostrils of lambs;
lesions of teats of nursing ewes;
persistent proliferative lesions;
scabs contain live virus
Orf (contagious pustular dermatitis)
how long does dry scab material remain infectious with Orf?
years
how to diagnose Orf
PCR or electron microscopy on moist scabs
what is the ‘treatment’ for orf
natural recover in 24-30 days;
prevent secondary infections
is there a vaccine for orf?
yes;
Scabivax (live vaccine)
name the skin disease of sheep
Corynebacterium pseudotuberculosis;
via skin abrasions;
abscesses in regional lymph nodes;
firm, palpable swellings involving lymph nodes of head and neck;
occasionally rupture and discharge pus
Caseous lymphadenitis
2 ways to diagnose caseous lymphadenitis
- bacterial culture from infected nodes
- ELISA serology
how long can the bacteria causing caseous lymphadenitis survive in sheep dip
up to 24h
what is the treatment for caseous lymphadenitis
none;
isolate or cull animals with discharging lesions
name the skin disease in sheep
primary: plants containing photodynamic agents (st. john’s wort);
secondary to hepatotoxic damage (Bog asphodal);
accumulation of chlorophyll metabolites, excretion blocked leads to reaction with sunlight
photosensitisation
name the skin disease in sheep
usually associated with prolonged wet weather;
papule and crust formation on ears, nose and dorsum;
generally NOT pruritic;
self-cure or antibiotics (penicillin)
Dermatophilosis (lumpy wool)
(Dermatophilus congolensis)
name 4 ways to classify ill-thrift in lambs
- failure to meet growth target
- failure to finish in time
- lack of response to increased feed
- poor body condition
this is the conversion of feed into meat;
aka Feed Conversion Efficiency (FCE)
growth
name the 2 wasy you can approach ill-thrift
- make assumptions and treat
- use rational, health plan-based approach
name 3 causes of ill-thrift that can be ruled out by post mortem examination
- pneumonia
- nematodes
- fluke
name the trace element deficiency
ill thrift in cattle and sheep;
poor reproductive performance (ewes and lambs);
white muscle disease (all ruminant species)
selenium
name the trace element deficiency
wool changes in sheep;
brittle bones
swayback in lambs, goats and deer;
ill thrift in cattle;
poor reproductive performance in cattle;
poor milk yields in cattle
copper
name the trace element deficiency
neonatal lamb and calf mortality;
poor reproductive performance
iodine
name the 4 main trace elements of interest in sheep
- copper
- cobalt
- selenium
- iodine
what type of blood tube should be used for cobalt testing
serum or heparin plasma
what vitamin is measured as a proxy of cobalt?
vitamin B12
what type of blood tube should be used for selenium testing
heparin plasma only
what enzyme can be measured as a proxy of selenium
GSHPx
name the 3 most commonly diagnosed foot conditions in sheep
- scald / interdigital dermatitis
- foot rot
- contagious ovine digital dermatitis (CODD)
name the foot disease in sheep
Dichelobacter nodosus +/- Fusobacterium necrophorum;
moist conditions or trauma lead to damage of the interdigital skin;
indistinguishable from benign foot rot;
often seen in lambs at grass
Scald (interdigital dermatitis)
what is the treatment for scald (interdigital dermatitis)?
antibiotic spray
(foot bathing in an outbreak)
what is the antibiotic of choice for ewes if footrot is present in farm
oxytetracycline
name the foot condition in sheep
Dichelobacter nodosus;
found on majority of farms and thrives in warm, wet conditions;
clinical cases of scald can incr. bacterial contamination and spread on farm;
foul smell and pus on the interdigital skin, underrunning of the horn starting from the interdigital space;
bacteria can survive 14d in environment
Footrot
name 2 treatments for footrot in sheep
- treat lame sheep as soon as noted
- topical and parenteral abx (oxytetracycline)
name 2 treatments that should NOT be done for sheep with footrot
- do NOT trim
- do NOT footbath
name the foot condition in sheep
lesions start at coronary band, ulceration, hair loss, underrunning of the horn starting at the coronary band, whole hoof may slough, regrowth may result in misshapen claws;
Treponema, D. nodosus and F. necrophorum have been isolated from these lesions but role in pathogenesis is uncertain;
lambs and ewes can be affected;
NO involvement of interdigital skin
contagious ovine digital dermatitis (CODD)
name the grade of contagious ovine digital dermatitis (CODD)
erosion/ulceration with or without hair loss can be seen at the level of the dorsal band
grade 1
name the grade of contagious ovine digital dermatitis (CODD)
erosion/ulceration of the skin at the coronary band with partial (less than 50%) under-running of the hoof horn dorsally, abaxially and tending towards circumferential under-running
grade 2
name the grade of contagious ovine digital dermatitis (CODD)
erosion/ulceration of the skin at the coronary band with 50-100% under-running of the hoof horn with possible hoof horn avulsion
grade 3
healing foot with the horn beginning to regrow, but an active lesion still present
grade 4
healed foot may have deformation of the regrown horn
grade 5
are goats cows or sheep?
No! they’re different :)
what is the current practice for treating contagious ovine digital dermatitis (CODD)
LA amoxycillin or macrolides
name the foot condition in sheep
caused by hoof damage - excessive paring or foot bathing;
can be a sequalae to infectious conditions such as footrot or CODD
toe granuloma
name 3 treatment options for toe granulomas in sheep
- paring to relieve pressure
- surgical removal
- digit amputation
name the foot condition of sheep
separation of the horn from the sole at the white line;
pain and lameness occurs if area becomes impacted;
damage from rough ground or poor hoof health due to nutritional issues are thought to predispose;
more prevalent in flocks with infectious lameness issues
Shelly hoof
what is the treatment for shelly hoof in sheep
pare away loose horn
(assess nutrition)
what is the target prevalence of lameness in sheep
< 2%
name the 5 point plan for preventing infectious lameness in sheep
- treat clinical cases promptly
- avoid spread if infection on farm
- quarantine incoming animals
- cull badly or repeatedly affected animals
- vaccinate against footrot biannual
what is the only infectious foot disease in sheep that should be treated with a footbath
scald
what is the vaccine that can be used at high risk periods (mainly spring and autumn) to help prevent infectious lameness in sheep
Footvax
(only licensed against footrot but also helps reduce risk of CODD)
name 4 cases where digit amputation should be used as a salvage procedure to treat foot disease in sheep
- septic pedal arthritis
- intractable toe granuloma
- swelling above coronary band unresponsive to Tx
- evidence of bony involvement with pain
why are goats so susceptible to poisoning?
they will eat anything
name 3 clinical signs of rhododendron poisoning in goats
- abdominal pain
- depression
- projectile vomiting
name the 4 main causes of diarrhoea in young goat kids
- dietary
- viral
- bacterial
- Cryptosporidium
name 3 main bacterial causes of diarrhoea in young goat kids
- E. coli
- Clostridium perfringens B, C
- Salmonellosis
name the 3 main causes of diarrhoea in older goat kids
- GI parasitism
- Coccidiosis
- Enterotoxaemia
what is the common presentation of coccidiosis in housed goat kids 3-7 weeks old?
watery, bloody scour with rapid dehydration
name 4 clinical signs of enterotoxaemia (Clostridium perfringens type D) in goats
- watery dysentery
- recumbency
- shock
- death
how often should goats be vaccinated against Clostridium with Lambivac?
every 6 months
name 2 treatments for goats with parasitic gastroenteritis
(Teladorsagia/Trichostrongylus, Haemonchus)
- fenbendazole
- ivermectin (not milkers)
which form of fascioliasis (Fasciola hepaticca) is more common in goats?
chronic form
what is the treatment for chronic liver fluke in goats?
albendazole
what is the treatment for acute liver fluke in goats?
triclabendazole
what is the most important way to control Johne’s in goats?
test & cull
what is the vaccine against Johne’s disease in goats and sheep?
Gudair
name 2 common infectious causes of abortion in goats
- Toxoplasmosis
- Chlamydophila abortus
what pathogen causes Pasteurellosis?
Mannheimia haemolytica
how to treat pasteurellosis in goats?
Oxytetracycline LA +/- NSAIDs
what medication for pasteurellosis is toxic to goats and canNOT be used?
Micotil
name two types of lungworms that can infect goats
- Dictyocaulus filaria
- Muellerius capillaris
which type of lungworm affects goat kids in late summer, esp SE England
Dictyocaulus filaria
what type of lungworm affects adult goats?
Muellerius capillaris
name the neonatal nervous disease of goats
epsilon toxin of Clostridium perfringens type D;
kids showing head pressing, tremors, ataxia and death;
control: vaccinate!
Tx: try Penicillin + steroid (avoid NSAIDs in kids)
Focal symmetrical encephalomalacia
name the neonatal nervous disease of goats
bacterial, usually E. coli secondary to septicaemia;
Tx: florfenicol (abx), anti-inflammatories, fluids +/- anti-convulsants;
cause: thermal due to excessive use of disbudding iron
meningoencephalitis
name the neonatal nervous disease of goats
togavirus transmitted by ticks;
sheep act as reservoirs
Louping Ill
name the neonatal nervous disease of goats
Anglo Nubians;
autosomal recessive lysosomal storage disease;
tremors, nystagmus, inability to stand, limb & joint defects
Beta mannosidosis
what type of antibiotic could be used to treat a spinal abscess
amoxiclav
name the nervous disease of goats aged 7mo-adult
usually over 2y old;
chronic weight loss/decreased milk yield;
then pruritis, hyperaesthesia and hind limb incoordination;
notifiable
Scrapie
name the nervous disease of goats aged 7mo-adult
L. monocytogenes encephalitis;
can cause rapid death within 6h;
not always circling;
Tx: IV penicillin, anti-inflammatories, fluids;
ZOONOTIC (milk & cheese)
Listeriosis
name the nervous disease of goats aged 7mo-adult
relative thiamine (vit B1) deficiency;
sietary change/prolonged scour/levamisole etc;
ruminal acidosis;
Tx: vit B1 (5-10 mg/kg) +/- anti-inflammatory + good roughage
CCN (cerebral cortical necrosis)
what is the treatment for mastitis in goats?
cattle tubes (under cascade)
(none licensed in goats)
what breed of goats commonly gets salivary cysts?
blockage of parotid/mandibular salivary;
painless fluid filled swelling
Anglo Nubians
name the disease affecting goats and sheep
enlarged peripheral lymph nodes - hard swelling, rupture to release thick green/cream pus;
chronic weight loss;
visceral form - lungs/kidneys as result of haematogenous spread;
NO treatment
caseous lymphadenitis (CLA)
what is the organism causing caseous lymphadenitis (CLA) in goats
Corynebacterium pseudotuberculosis
what event can be a big risk factor for transmitting caseous lymphadenitis (CLA) in sheep and goats?
shearing
name the disease affecting goats
parapox virus;
more susceptible than sheep;
lesions around the mouth, teats and coronary band;
Abx in severe cases to control secondary bacterial infection;
Scabivax Forte vaccine is effective (vax in tail fold/inner thigh)
Orf
name the species of biting lice affecting goats
Damalinia caprae
name the species of sucking lice affecting goats
Linognathus stenopsis
what is the treatment for lice in goats?
synthetic pyrethroid pour-ons
what is the treatment for mange in goats?
endectocide (2 doses or long acting)
name the disease affecting goats
lentivirus closely related to Maedi Visna Virus;
carriers infected for life;
transmission: mainly via milk/colostrum;
clinical sings:
1. arthritis is the most common presentation - gradual loss of condition leading to emaciation
2. encephalitis
3. pneumonia
4. mastitis
Caprine Arthritis Encephalitis (CAE)
name the contagious cause of abortion in goats
not solid immunity - remain infected, may abort again;
infection via milk - ZOONOTIC!
Toxoplasmosis
name the contagious cause of abortion in goats
abort any stage of gestation;
infection and abortion in same pregnancy possible;
carrier animals (kids born to infected does);
vaccination not licensed
Chlamydophila abortus
name the disease of goats
fluid accumulation in uterus with presence of persistant CL;
following cycle with no pregnancy or after embryonic death and resorption;
“cloudburst” - release of fluid;
diagnosis: U/S scan, high progesterone and oestrone sulphate in milk or plasma
hydrometra
what is the treatment for hydrometra in goats?
1mL Estrumate and oxytocin 2-3d later
can you give xylazine IV to goats and sheep?
NO
do NOT give Alpha-2’s IV to small ruminants, they WILL die - give IM
name 4 clinical signs that many respiratory diseases in sheep present with
- incr resp rate and effort
- depression
- incr nasal discharge
- fever
name 5 significant signs of respiratory disease in sheep that can help with diagnosis
- resp character
- coughing
- nasal discharge
- dyspnoea
- adventitious sounds
name the 3 pathogens that can be the cause of Pasteurellosis in sheep?
- Mannheimia haemolytica
- Bibersteinia trehalosi
- Pasteurella multocida
name 3 diseases that can be caused in sheep by Mannheimia haemolytica
- pneumonia in growing lambs/adults
- septicaemia in young lambs
- mastitis in ewes
what sign is often seen first with M. haemolytica in sheep?
sudden deaths
name 5 clinical signs of pneumonic acute pasteurellosis in sheep
- sudden onset anorexia and dullness
- pyrexia
- hyperpnoea/dyspnoea
- serous ocular/nasal discharges
- frothy fluid at mouth terminally
name 3 pathological lesions of pneumonic hyperacute pasteurellosis in sheep
- ecchymotic haemorrhages over throat and ribs
- lungs swollen, purple-red
- pink stained froth in airways
name 5 clinical signs of M. haemolytica septicaemic pasteurellosis in sheep
- sudden death (lambs up to 12wks)
- depressed
- injected mucus membranes
- marked dyspnoea
- most pyrexic
name 4 pathological lesions seen with septicaemic pasteurellosis in sheep
- pleurisy and pericarditis
- petechiae in myocardium, spleen, liver, kidney (any septicaemia)
- enlarged LNs
- hepatic fatty change
how to diagnose M. haemolytica in sheep?
PM findings
(NOT swabs/serology in live animal - commensal)
name 3 treatments for clinical cases of M. haemolytica in sheep
- oxytetracycline
- tilmicosin
- NSAID
name 3 pasteurella vaccines (Intervet)
- heptavac P plus
- ovivac P plus
- ovipast plus
name the most likely cause of systemic pasteurellosis
oct, nov, dec;
most commonly diagnosed cause of sudden death in lambs July-Dec;
movement onto rap, turnips or improved pastures;
outbreaks start with sudden deaths;
commensal bacteria;
GI erosions, septicaemic disease;
other conditions (cobalt deficiency) may predispose
Bibersteinia trehalosi
name 5 pathological lesions seen with systemic pasteurellosis caused by Bibersteinia trehalosi in sheep
- haemorrhages
- swollen lungs with haemorrhages (no congestion)
- necrotic erosions
- liver congestion
- necrotic infarcts
acute respiratory diseases in sheep are dominated by what pathogen?
Mannheimia haemolytica
name the acute viral infection in sheep
most infections subclinical or mild;
most infected by 12mo old;
maintained by transient or persistent infections;
predispose to infection with M. haemolytica;
diagnosis is rarely attempted;
can be given IN vaccine to control
PI3
(parainfluenza virus type 3)
name the acute viral infection in sheep
infection common in young lambs;
transient or persistent inapparent infection;
enteritis;
vax in Hungary
adenovirus
name the respiratory disease fo sheep
non-progressive chronic pneumonia of housed sheep under 1y old;
caused by Mycoplasma ovipneumoniae;
PI3 and M. haemolytica are predisposing factors;
growing lambs, chronic soft cough, growht rates affected
atypical pneumonia
name 2 pathological/histological lesions associated with atypical pneumonia in sheep
- red-brown or grey consolidation of apical and cardiac lobes
- lymphocytic cuffing pneumonia
what is the treatment for atypical pneumonia in sick lambs
oxytetracycline OR macrolide
name 3 important ways to control atypical pneumonia in sheep
- improve ventilation
- reduce stocking densities
- avoid sharing airspace with older sheep
name the cause of parasitic bronchitis
most pathogenic;
deaths uncommon;
outbreaks of coughing and weight loss (late autumn/early winter);
may trigger secondary pasteurellosis;
L1 passed in faeces, develop to L3 on pasture, adult worms in bronchi
Dictyocaulus filaria
name 3 causes of parasitic bronchitis in sheep
- Dictyocaulus filaria
- Protostrongylus rufescens
- Muellerius capillaris
name the pathology seen witrh Muellerius capillaris in sheep
green/grey sub-pleural nodules in dorsal/caudal lung lobes
name the pathology seen with Protostrongylus rufescens in sheep
small yellow/grey granulomas in the caudal lobes
name 2 clinical signs of chronic suppurative pneumonia in sheep
- weight loss/ill thrift in individual animals
- change in resp character
what is the treatment for chronic suppurative pneumonia in valuable animals
4wks procaine penicillin
name the repiratory disease of sheep
texels and suffolks;
often about 2y old;
lat summer/autumn (breeding season, feeding);
conformation/trauma/dust/infection;
oedema, respiratory distress;
mucosal ulceration leading to arytenoid abscessation
laryngeal chondritis
name the 4 main clinical signs of laryngeal chondritis in sheep
- acute onset severe respiratory distress
- inspiratory stridor and effort
- salivation
- cyanosis
what are the 2 treatments for laryngeal chondritis in sheep
- 20mg dexamethasone IV
- 7-10d abx (tulathromycin, synulox, micotil)
name the respiratory disease in sheep
1-3d after bloom dips;
acute pneumonia;
severe dyspnoea;
high mortality rate;
severe red/purple consolidation;
diagnosis confirmed on histopathology;
symptomatic treatment, wash fleece
phenolic dip aspiration
name the respiratory disease in sheep
signs: sneezing and gadding, rhinitis, head shaking, excitability;
+/- blindness, pneumonia, death;
adults deposit L1 in nasal cavity, moult to L3 in sinuses, sneezed out after 40d, pupate in soil for 17-70d;
2 generations during summer
oestrus ovis
(nasal bot fly)
name the 5 main reasons camelids are kept in the UK
- breeding for sale
- companionship
- fibre production
- posh lawn mower
- guard animals for sheep
what are male alpacas/llamas called
machos
what are femal alpacas/llamas called?
hembras
what are young alpacas/llamas called?
cria
what is the mature weight of an alpaca
55-90kg
what is the mature weight of a llama
110-250kg
what type of digestion do camelids have?
fore-gut fermenters
(ruminant analogues)
how many compartments does a camelids stomach have?
3 compartments
which ruminant stomach is compartment C1 of the camelid stomach analogous to?
rumen
which ruminant stomach is compartment C2 of the camelid stomach analogous to?
reticulum
starvation of this many days may cause death of bacteria and protozoa in compartments C1-C2 of the camelid stomach
3-5d
what should camelid nutrition be made up of?
grass & hay sufficient
what type of food should be avoided in camelids?
concentrates (esp those for monogastric animals)
what is the normal rectal temperature for alpacas
37.5-28.9°C
what is the nirmal heart rate for an alpaca
60-90 bpm
what is the normal timing for gut contractions for alpacas
3-4 per min
where to take a blood sample from an alpaca
right jugular vein in lower third of neck
(more ventral than in other species)
at what age do alpacas become sexually mature
1 year of age
what percent of mature body weight should camelids be at for breeding
60%
when is the highest conception rate for alpacas
20-30d post parturition
what type of ovulators are alpacas?
induced ovulators
how long is alpaca gestation?
340d +/- 25d
what do alpacas do 7 days post-mating which can help with pregnancy diagnosis
“spit off”
how long is stage 1 of labour in alpacas
1.5-2h
how long should stage 2 of labour in alpacas last?
no more than 30 min
foetal membranes should be expelled within how long following parturition
6h
how long should it take a healthy cria to sit up
within 10min
how long should it take a healthy cria to stand
within 1h
how long should it take a healthy cria to nurse
within 3-4h
when should healthy cria be weaned
6mo
what should be used to treat endoparasitism in alpacas
sheep anthelmintics
name 2 biochemistry signs of liver fluke in alpacas
- decr albumin
- incr GGT
what to treat liver fluke with in alpacas
- clorsulon 7mg/kg PO twice every 60d
- Albendazole 10-20mg/kg PO (NOT for crias due to potential toxicity)
name the cause of coccidiosis in alpacas
Eimeria macusaniensis (‘I-mac’)
what biochem sign will be seen in alpacas with coccidiosis
hypoalbuminaemia
(normal PCV)
how to treat coccidiosis in alpacas
sulfadimethoxine for 5d
what does a normal alpaca RBC look like?
flattened oval RBC
how to diagnose Mycoplasma haemolamina in alpacas?
Wrights Geimsa stain on fresh blood smear
how to treat Mycoplasma haemolamina in alpacas?
oxytetracycline 15d
(does not clear)
what might induce Mycoplasma haemolamina in alpacas?
steroid treatment
what is the most common pruritic skin condition in alpacas?
chorioptic mange
how to treat mange in alpacas?
ivermectin injection every 10-15d for 4 doses
how to treat biting lice in alpacas?
fipronal
how to treat sucking lice in alpacas?
ivermectin
how to diagnose chorioptic mange in alpacas?
tape strip in multiple areas
(live in colonies)
what colour alpacas are more susceptible to hypovitaminosis D?
black animals
what is the standard for preventing hypovitaminosis D in alpacas?
prophylactic vit D injections
(esp in winter)
name 6 results of hypovitaminosis D in alpacas
- ill thrift
- poor coat
- poor repro performance
- osteoporosis
- angular limb deformities
- pathological fracture
name the 3 main causes of anaemia in alpacas
- GI parasitism (Haemonchus)
- mycoplasma haemolamae
- acute fluke
how to treat gastric ulcers in alpacas?
injectable omeprazole
how to diagnose tuberculosis in alpacas
enerflex test on blood (Ab ELISA + lateral flow Ab test)
(must request permission to test from APHA)
name 5 common causes of hypoalbuminaemia in alpacas
- GI nematodes
- chronic fluke
- coccidiosis
- chronic liver disease
- Johne’s disease
name the pathogen causing alpaca fever
Streptococcus zooepidemicus
name the 3 main clinical signs of alpaca fever
- anorexia
- recumbency
- pyrexia (41°C)
(death in 4-8d)
how to treat alpaca fever
penicillin
what is the triple anaesthetic combo used in alpacas?
good sedation, recumbenxy & analgesia
xylazine, ketamine, butorphanol
this is the effort to breed sheep who limit the survival of worm parasites;
positive effects only when animal is 4mo+
host resistance
this is the ability of the host to tolerate a worm burden;
environment can be manipulated to support this
host resilience
what factor influences host resistance?
genetics
name 5 factors that influence host resilience
- nutrition (CP)
- health status
- parasite load
- genetics
- grazing management
name 6 common clinical signs of nematodes/worms
- ill thrift
- weight loss
- scour
- lethargy/dullness
- pale MMs
- sudden death
name 3 differentials for parasitic gastroenteritis (PGE) in lambs at pasture (diarrhoea 3-6mo of age)
- nutritional
- coccidiosis
- salmonella
name the 3 broad categories of nematodes in sheep
- haemonchus
- nematodirus
- lungworms
name the neatode larvae stage
remain in faeces, feeding on bacteria
L1 & L2
name the neatode larvae stage
remain sheath, can’t feed;
survives on lipid stores;
killed off by UK light;
survive unfavourable environments better;
infective stage
L3
name the nematode
warmer temps (>20C);
>5000 eggs per day;
blood feeding adults;
can also hypobiose;
delayed immunity: 6mo old, adults can ‘self cure’
Haemonchus contortus
(Barber’s pole worm)
this something done by Haemonchus nematodes;
interrupting larval development at L4 stage to survive the winter;
resume development and become egg-laying adults in spring
Hypobiosis
what is the main clinical sign of Haemonchus contortus (Barber’s pole worm) in sheep?
anaemia
(usually NO diarrhoea)
name the nematode
L3 is developed in the egg, hatching correlated to weather pattern: cold stap (<10C) followed by temperatures 10-17C (usually april-june);
severe outbreaks when lambs are 6-12wks;
transmission from lamb to lamb!
Nematodirus battus
(& N. filicollis)
name 5 clinical signs of Nematodirus battus in lambs
- acute scour
- loss appetite
- dehydration
- painful abdomen
- sudden death
name the nematode affecting sheep
most common species in PGE;
hyperplastic gastritis leads to damaged gastric glands leading to hypoproteaemia and hypoalbuminaemia;
hypobiosis in abomasum over winter;
causes dehydration, permanent damage;
related to osertagia in cattle
Telodorsagia circumcincta
(Brown stomach worm)
when do cattle acquire immunity to Cooperia?
within 1 year
when do cattle acquire immunity to Ostertagia?
within 2 years
name the type of Ostertagia disease in cattle
dairy calves 2mo after turn out, beef calves in autumn when weaned;
appetitie loss, rapid weight loss, watery scour, high morbidity, low mortality;
typical PGE
Type 1 Ostertagia
name the type of Ostertagia disease in cattle
less common;
larvae can go into hypobiosis, L4 larvae become dormant ingastric glands;
damage to abomasum can be more severe;
ill-thrift, weight loss, watery scour, sub-mandibular oedema
Type 2 Ostertagiosis
name 3 differential diagnoses for type 1 ostertagiosis in cattle
- coccidiosis
- Salmonellosis
- BVDV
name 2 differential diagnoses for type 2 Ostertagiosis in cattle
- chronic liver fluke
- metabolic acidosis
name the nematode affecting cattle
older animals are carriers;
weather & pasture management have enormous impact on hatching of eggs and larval dispersal;
warm (20C), humid, wet weather is optimal;
L1-L3 in 1wk;
larvae is short-lived if weather is hot and dry;
causes tachypnoea and coughing
Lung worm - Dictyocaulus viviparus
how long does immunity to lungworm larvae last in cattle?
4-6mo
how long does immunity to adult lungworms last in cattle?
2 years
what chart can be used to detect anaemia?
FAMACHA charts
why might a FEC for suspected Type 2 ostertagiosis be a false negative?
encysted (hypobiosed) larvae
levels of this in serum plasma can correlate to abomasal pathology
pepsinogen
this is when the host limits parasite burden;
lower number of parasites = lower pasture contamination
parasite resistance
this is when the host withstands parasite burden;
continue to grow, maintain condition, lactate etc in spite of worm burden;
so, no reduction in parasite burden/pasture contamination
parasite resilience
which would lead to lower levels of egg excretion in the hosts faeces?
parasite resistance or resilience?
parasite resistance
how many grazing seasons does it take for sheep to develop acquired immunity to nematode gut worms
1 grazing season
(only 3-4wks for Nematodirus)
how many grazing seasons does it take for cattle to develop acquired immunity to nematode gut worms
two grazing seasons
when does sheep immunity to nematodes wane?
during peri-parturient rise
how long does cattle immunity to D. viviparous last?
6 months
what type of nematode is the only currently successful vaccine for?
lungworm
(live, given orally, lasts 6mo)
name 3 limitations around use of live lungworm vaccine
- compliance with vaccine protol
- can’t use at same time as wormer
- protection limited in face of very high challenge
what is the Lungworm vaccine protocol?
8wks old+, booster in 4wks
all while animal is NOT out at grass
(ongoing exposure at pasture then required for adequate immunity)
what type of drugs are anthelmintics?
POM-VPS
(vet, pharmacist, SQP can prescribe)
these are drugs which either paralyse or kill heminths without damaging the host;
often used to reduce the worm burden (prophylaxis rather than cure)
anthelmintics
what anthelmintic drug colour group are Benzimadazoles (Fenbendazole) part of?
white
what anthelmintic drug colour group is Levamisole part of?
yellow
what anthelmintic drug colour group are Macrocytic Lactones (moxidectin) part of?
clear
what anthelmintic drug colour group is Monopantel part of?
orange
what anthelmintic drug colour group are ML & Derquantel part of?
purple
which colour of anthelmintics are the only ones effective against tapeworms (and used to treat adult fluke)
white
(Benzimadazoles - fenbendazole)
which two colours of anthelmintics can treat encysted nematodes?
- white (benzimadazoles - fenbendazole)
- clear (macrocytic lactones - moxidectin)
name two flukicides (anthelmintics) that are active against Haemonchus bc they are bound to plasma albumin
- Nitroxynil
- Closantel
this is the heritable reduction (by the parasite!) in the sensitivity of a parasite population to the action of an anthelmintic
anthelmintic resistance
name 4 risk factors for anthelmintic resistance
- over dose
- under dosing
- refugia
- buying in worm resistant parasites
historically, where is the biggest risk for liver fluke in the UK?
Western UK
(wet and humid)
what is the definitive host of liverfluke
ruminants
if the weather is below this temp, fluke eggs don’t hatch and snail development is halted
< 10°C
how long does it take miracidia (liverfluke larval stage) in 10-15°C
6 weeks
which liverfluke larval stage is released from the snail in moist, slightly acidic marshy soils?
cercaria
which liverfluke larval stage can overwinter and infect ruminants 10-12wks post ingestion?
metacercaria
what is the species of snail that is necessary for the lifecycle of Fasciola hepatica?
Galba truncatula
what type of immune resposes do ruminants have for early acute fluke migration?
Th1
what type of immune responses do ruminants have for acute-chronic stages of liverfluke?
Th2
what co-infection can ruminants have due to migrating juvenile liverflukes?
Black’s disease
(Clostridium novyii)
what is the only type of fascioliasis that cattle get?
chronic
(sheep get acute, sub-acute & chronic)
name 4 clinical signs of acute fasciolosis
- sudden death
- lethargy
- anaemia
- submandibular oedema (bottle jaw)
what months is acute faciolosis most commonly seen in sheep?
July-December
what months is subacute fasciolosis most commonly seen in sheep?
October-January
name 4 clinical signs of subacute fasciolosis in sheep?
- rapid weight loss
- anaemia
- submandibular oedema
- death
what months is chronic fasciolosis most commonly seen in sheep?
December-April
name 5 clinical signs of chronic liver fluke in sheep
- ill-thrift
- anaemia
- submandibular oedema
- ascites/scour
- secondary photosensitisation
name the 2 main clinical signs of chronic fasciolosis in cattle
(often sub-clinical)
- progressive weight loss (“ill thrift”)
- reduced production
name the fluke species present in the Western Isles of Scotland;
disease with mass infection, liver condemns, photosensitisation;
affects sheep
Dicrocoelium dentriticum
name the species causing Rumen fluke/paramphistomes ;
similar lifecycle to liver fluke;
adults in rumen likely harmless, but juveniles burden in duodenum causing ill-thrift and foetid black scour;
youngstock affected
Calicophoron daubneyi
name the fluke diagnostic test
not specific for liver fluke, not recommended as a stand-alone test, requires supporting evidence;
can be used any time of year but requires careful interpretations;
for fluke ages 2-12+ wks
liver/bile duct enzymes
name the fluke diagnostic test
earliest reliable indicator (2-4wks post-infection) specific for fluke;
can stay positive even after successful treatment;
best time to use from mid-summer onwards, best in young first season grazing animals (sentinel lambs) ;
for fluke age 2-12+wks
serum/blood ELISA
name the fluke diagnostic test
second earliest indicator (6-7wks post-infection);
good indicator of treatment outcome;
best time from late summer onwards, depending on the weather, can be used in young & older animals;
for fluke ages 6-12+wks
Faecal or coproantigen (cELISA)
name the fluke diagnostic test
latest indicator (10-12wks post-infection);
works well as composite test, good monitoring tool;
best used from autumn onwards, depending on the weather, can be used on young & older animals;
for fluke ages 10-12+wks
faecal sedimentation
name the only anthelmintic that can treat early immature (2wks) Fasciola hepatica
Triclabendazole
name the 4 anthelmintics that can treat immature (6-8wks) Fasciola hepatica
- Triclabendazole
- Rafoxanide
- Closantel
- Nitroxynil
name the 7 anthelmintics that can be used to treat adult Fasciola hepatica
- Triclabendazole
- Rafoxanide
- Closantel
- Nitroxynil
- Clorsulon
- Oxclozanide
- Albendazole
name the only 3 anthelmintics that should be used to treat Fasciola hepatica in dairy cattle
(50 day milk WHP)
- Albendazole
- Oxyclozanide
- Triclabendazole
name 2 ways to diagnose triclabendazole resistance
- Faecal Egg Count Reduction Test (FECRT)
- Coproantigen reduction test
when doing a coproantigen reduction test to look for triclabendazole resistance, how much should positivity drop by to show that triclabendazole is still effective?
at least 90%
what is the definitive host for all significant species of cestodes?
(except Monezia expansa and Taenia saginata)
canids
what is the intermediate host for Monezia expansa (cestode)
pasture mite
name the 2 cestode species that do NOT have canids as the definitive host
- Monezia expansa
- Taenia saginata
what is the definitive host for Monezia expansa (cestode)
sheep
what is the intermediate host for Taenia saginata (cestode)
cattle
what is the definitive host for Taenia saginata (cestode)
humans
what should dogs be wormed with every 3 months to control cestodes in sheep
praziquantel
how long post-ingestion are clinical signs of Taenia multiceps seen in sheep?
2-6mo
name 3 clinical signs of Taenia multiceps in sheep
- blindness, proprioceptive defects
- depression, head pressing
- localised softening of skull
name 5 cestodes in sheep
- Monezia expansa
- Taenia hydatigena
- Taenia multiceps
- Taenia ovis
- Echinococcus granulosus
name 3 cestodes in cattle
- Taenia saginata
- Taenia hydatigena
- Echinococcus granulosus
name 3 factors that can be manipulated to have better outcomes in parasite control
- host
- environment
- parasite
rank the pasture risk for sheep nematodes
Spring:
ewes and lambs in the previous year
goats the previous year;
store/ewe lambs the previous autumn/winter ;
for Nematodirus carried ewes and lambs in the previous spring
High
rank the pasture risk for sheep nematodes
Spring:
grazed only by adult non-lactating sheep the previous year;
grazed by ewes and lambs previous spring but then conserved and aftermath not grazed by sheep
Medium
rank the pasture risk for sheep nematodes
Spring:
new lets/seeds or forage crops;
cattle or conservation only in the previous year
low
rank the pasture risk for sheep nematodes
Summer:
ewes and lambs in the spring
High
rank the pasture risk for sheep nematodes
Summer:
adult non-lactating sheep only in the spring;
cattle or conservation in the spring
medium
rank the pasture risk for sheep nematodes
Summer:
cattle or conservation only in the first half of the grazing season;
forage crops or arable by-products
low
rank the pasture risk for sheep nematodes
late season/autumn:
ewes and lambs all season
high
rank the pasture risk for sheep nematodes
late season/autumn:
grazed by cattle since mid-season;
grazed by mature dry ewes since weaning mid-season
medium
rank the pasture risk for sheep nematodes
late season/autumn:
cattle or conservation only in the first half of the grazing season;
forage crops or arable by-products
low
rank the pasture risk for cattle lungworm
Spring:
grazed by first-grazing season calves in previous year;
grazed by lungworm-infected cattle in the previous year
high
rank the pasture risk for cattle lungworm
spring:
grazed only by cows or yearling cattle with no history of hoose inthe previous year
medium
rank the pasture risk for cattle lungworm
spring:
new pasure;
grazed by sheep or used for hay or silage only in the previous year
low
rank the pasture risk for cattle lungworm
mid-summer:
grazed by first grazing season calves in the spring
high
rank the pasture risk for cattle lungworm
mid-summer:
grazed by cows and yearling cattle with no history of hoose
medium
rank the pasture risk for cattle lungworm
mid-summer:
grazed by sheep or after grass (used only for silage or hay in the first half of the season) i.e. never grazed in current grazing season
low
this is an algorithm which calculates individual animals target weight every month;
animal treated if not reaching weight targets
targeted selective treatment (TST)
