Infectious Diseases Flashcards
CA02; CA9-10; CA20-22; CA12-13; CA23-24
name 4 clinical signs of acidosis
- mental obtundation
- decreased suck reflex
- muscle weakness
- gut stasis
name 4 clinical signs of dehydration
- skin tent
- enopthalmos
- cold extremities
- tachycardia
how much oral fluids should be given to a dehydrated calf?
1-2L every 4-6h
what is the maintenance rate of IV fluids for a calf
5mL/kg per hour
what molecule should oral fluid therapy contain in order to treat a calf with acidosis
bicarbonate
(or one of its precursors)
what is the degree of acidosis?
alert and standing;
no skin tent or enopthalmos
no acidosis
what is the degree of acidosis?
standing securely;
enopthalmos
mild acidosis
(base deficit about 10mmol/L)
what is the degree of acidosis?
tired or listless;
wobbly;
aid to stand
moderate acidosis
(base deficit about 20mmol/L)
what is the degree of acidosis?
comatose or obtunded;
sternal or lateral recumbency;
impaired palpebral reflex
severe acidosis
(base deficit >20mmol/L)
what is the equation for the total base replacement (mmol) by IV therapy for a calf with acidosis
total base replacement = body weight (kg) x base deficit (mmol/L) x distribution of bicarb in the ECF (0.7 L/kg)
name the type of IV fluid
contains lactate (which is metabolised to bicarb);
mix of D-lactate & L-lactate;
calves cannot fully utilise D-lactate so less bicarb is produced;
not ideal but can help if all you have
Hartmanns
what is the most prevalent (infectious) cause of diarrhoea in a calf <7 days old
bacteria
(LESS acidotic than older calves)
what is the most prevalent (infectious) cause of diarrhoea in a calf 7-21 days old
virus
(usually acidotic)
what is the most prevalent (infectious) cause of diarrhoea in a calf >1 month old
parasite
(not acidotic)
what 4 causes of diarrhoea does a calf side scour SNAP test diagnose
- E coli
- Rotavirus
- Coronavirus
- Cryptosporidia
name the infectious cause of diarrhoea in calves
multiplies and releases enterotoxin which upregulates chloride secretion, increases osmotic potential of GIT contents so water is drawn into the lumen causing secretory diarrhoea;
rapid dehydration through faecal fluid loss and decr. fluid intake due to anorexia
E. coli
name the infectious cause of diarrhoea in calves
replicates in epithelial cells of small intestinal villi;
destruction of mature enterocytes in the villi;
secretion of a viral enterotoxin and atrophy of sm. intestine villi & colonic crypts causes malabsorptive diarrhoea leading to dehydration and acidosis
rotavirus
what 3 pathogens is Bovilis used to vaccinate against (active immunisation of pregnant cows and heifers to raise Abs against them)
- E. coli
- rotavirus
- coronavirus
name 2 treatment options for Cryptosporidia
- Parofor crypto
- Halocur
name 2 ways to diagnose coccidiosis
- McMasters
- Sporulation (for species)
name 2 treatment options for coccidiosis
- Diclazuril (Vecoxan)
- Toltrazuril (Baycox)
name 3 common bacterial/viral causes of diarrhoea in an adult cow
- Johne’s
- Salmonella
- Winter dysentery
what are the 3 main differential diagnoses for winter dysentry in adult cattle
- salmonellosis
- dietary upset
- SARA
what is the treatment for winter dysentery in adult cattle
symptomatic
(usually resolves with no treatment)
what is the most common type of Salmonella in UK cattle?
also causes abortion; NOT zoonotic
Salmonella Dublin
this is a common type of salmonella that causes salmonellosis in cattle and IS zoonotic
Salmonella Typhimurium
name 4 main ways Salmonella gets into a farm
- bought in animals
- slurry spreading
- vermin/birds
- vets & other visitors
what age of calves (mainly) are affected by Salmonella
2-6 weeks
what is the name of the vaccine used to prevent/control Salmonella (killed/inactivated vaccine for S. Dublin & S. Typhimurium);
reduce shedding and help protect in-contacts by reducing environmental contamination
Bovivac S
name the term
the study of how often disease occurs in different groups of animals and why
epidemiology
name the term
a disease which is consistently present in a particular population or region
endemic disease
name the term
an infectious disease that does not normally occur in a particular region
exotic disease
this is the average number of secondary cases produced in a naive population from one infectious individual
R_0
in endemic disease, what does R_0 usually equal?
1
what must R_0 be in order for an infection to spread in a naive population?
R_0 > 1
what are the 4 pillars of / what 4 things does the health status of any herd depend on?
- Biosecurity
- Surveillance
- Immunity
- Biocontainment
name the pillar of herd health status
risk of disease entering a herd;
depends on disease mode of transmission, farm biosecurity, buying history and geographical situation
biosecurity
name the pillar of herd health status
on farm - do we know what diseases are circulating on farm?
depends on current testing and scheme membership
surveillance
name the pillar of herd health status
on farm - depends on current and historical disease circulation, vaccination history and herd origin
immunity
name the pillar of herd health status
risk of disease spreading on farm;
depends on housing and management practices
biocontainment
where/what does Leptospirosis infect cattle through
mucous membranes
where does Leptospirosis localise following infection through mucous membranes
- repro tract
- kidneys
- udder
how is Leptospirosis spread/transmissed
infected urine
name 4 risk factors for Leptospirosis in cattle
- co-grazing with sheep
- shared water courses
- open herd
- shared bulls
how long can infected cattle remain hosts of Leptospirosis for?
years
what are the 3 main clinical signs of Leptospirosis in cattle?
- milk drop
- abortion
- infertility
how to diagnose Leptospirosis on a herd level?
bulk milk ELISA
what is the treatment for Leptospirosis?
Pen Strep
(Oxytetracycline or amoxyxillin also effective)
name the 2 vaccinations for Leptospirosis in cattle
- Spirovac
- Leptavoid-H
name the 3 official control programmes for Leptospirosis in cattle
- Accredited Free programme
- Monitored Free Programme
- Eradication Programme
what protozoan parasite is one of the most important cause of bovine abortion?
Neospora
what is the definitive host of Neospora?
dogs
name the two forms that Neospora exists in
- Tachyzoite
- Bradyzoite
name the form of Neospora
actively multiplying stage that migrates through the body in the acute stage of infection
tachyzoite stage
name the form of Neospora
part of the chronic infection when the parasite persist within the cell in tissue cysts
bradyzoite stage
this can occur when bradyzoite stage of Neospora are reactivated to the tachyzoite stage and spread throughout the body again
recrudescence
name the 2 most important transmission routes of Neospora in herds
- abortion storm (outbreak - dog horizontal)
- endemic abortions (cow vertical)
what does vertical transmission of Neospora ocurring in mid to late gestation result in?
persistently infected calf
what does horizontal Neospora infection early in pregnancy in cattle result in?
abortion
name the 3 main risk factors for neospora transmission in cattle
- contact with dog faeces
- persistently infected (PI) cattle
- buying in infected cattle
is there a treatment or licensed vaccine in the UK for Neospora?
no
name the 2 way approach to reduce transmission risk of neospora in cattle
- test & cull cattle (diagnose)
- management (prevent exposure/contact)
name 4 reasons for limited options of control programmes for neospora in cattle
- sporadic incursions
- persistent infection
- low diagnostic sensitivity & few clinical signs
- no vaccine or treatment
what does DIVA stand for in terms of diagnostic pathogen testing
Differentiate Infected from Vaccinated Animals
this is the ability of a test to correctly classify animals as positive
(false negatives)
rule OUT the diagnosis - high this means few false negatives
sensitivity
this is the ability of a test to correctly classify animals as negative
(false positives)
rule IN the diagnosis - high this means few false positives
specificity
what pathogen causes Johne’s disease
Mycobacterium avium subspecies paratuberculosis (MAP)
when does clinical disease of Johne’s disease typically occur in cattle?
3-5y of age
(neonatal infection)
what is the primary transmission of Johne’s disease
faeco-oral
(calf infected from dirty teats, contaminated milk, etc)
where does Johne’s disease localise after ingestion?
gut
what type of cell takes up MAP (Johne’s disease pathogen) intracellularly where it can remain latent for years until a stress event?
macrophages
what is the post-mortem pathology of Johne’s disease
chronic granulomatous enteritis
(thickening of intestinal wall, enlarged LNs)
what condition (clinical signs) does the clinical pathology of Johne’s disease result in
protein-losing enteropathy with subsequent hypoalbuminaemia
(weight loss, diarrhoea, oedema, bright demeanour and good appetite)
name the 4 main risk areas of Johne’s disease spread on farm
- infected adult cattle
- management at calving
- management of colostrum and milk
- young stock management
name the two way approach to reduce transmission risk of Johne’s disease
- test & cull
- management
what testing should be done in beef cattle herds for Johne’s disease
screen breeding animals > 2y
(don’t forget the bull)
what testing should be done in dairy cattle herds for Johne’s Disease
bulk milk / cull cow screen / targeted 30 cow screen
(quarterly testing)
name the 6 strategies to control Johne’s disease within dairy herds outlined in the National Johne’s Management Plan (NJMP)
- biosecurity protect and monitor
- improved farm management
- strategic testing
- test and cull
- breed to terminal sire
- firebreak vaccination
this should outline the disease status of the farm identifying the key challenges and areas of risk;
provides a framework for disease prevention strategies, such as vaccination, outlines how existing issues are to be tackled and measured, and monitors animal health and productivity
herd health plan
name the CHeCS 5 steps to controlling or eliminating disease
- establish herd disease health status
- decide if you want to prevent, manage or eradicate disease
- implement a protocol that will help achieve your goal
- monitor progress
- reassess disease status
name the 2 distinct forms (biotypes) of Bovine Viral Diarrhoea Virus (BVDV)
- cytopathic form (cpBVD)
- non-cytopathic form (ncpBVD)
what are most losses from BVDV associated with
loss of production
what is the main source of BVDV?
viraemic cattle
(usually exposed to a PI or transiently infected animal)
when must a calf be infected by BVDV in order to become persistently infected
in-utero prior to immunocompetence (<110 days)
what disease might a calf persistently infected with BVDV eventually succumb to
Mucosal Disease (MD)
what clinical signs might a calf have if the Dam is infected with BVDV between 90-150 days of gestation?
congenital defects
(cerebellar hypoplasia, blindness, ataxia)
what is the treatment for acute BVD (transient infection)
symptomatic supportive treatment for secondary disease;
should recover
what is the treatment for persistently infected (PI) cattle with BVD
cull
what is the treatment for a PI BVD cow with mucosal disease
cull (no effective treatment)
name 2 vaccine options for BVD
- Bovela (modified live)
- Bovillis (inactivated)
what is the average lifespan of Holstein cows in the UK
3.6 lactations
what is the biggest cost in milk production?
feed costs
what are the big 3 reasons for culling dairy cows
(forced, involuntary culls)
- infertility
- mastitis
- lameness
name 2 major ‘selected’ or voluntary reasons for culling a dairy cow
- poor milk yields
- age
(temperament, slow milker, condition, etc)
what is the biggest reason for culling adult dairy cows?
infertility
how many lactations must a heifer reach to make a profit at 22 pence per liter?
3rd lactation
name 2 reasons a farmer might be unaware of the problems with production diseases on the farm
- poor records
- only see individual cases
name 3 conditions/other diseases milk fever may result in
- dystocia
- endometritis
- mastitis
name 6 direct costs of production diseases in a dairy herd
- treatment costs
- vet bills
- labour costs
- reduction in milk yield
- discarded milk
- death
name 5 indirect costs of production diseases in a dairy herd
- incr. culling rate
- risk of fatality
- risk of other disease
- extended calving interval
- extra services per conception
what is the cost of infertility for each day over a 365 day calving index?
£4
name 4 things the cost of infertility in a dairy cow would include
- lost revenue for milk
- extra food and housing for longer dry period
- reduction in calf production
- extra services per cow
what is the current UK average of mastitis cases per 100 cows
40 cases for every 100 cows
what is the average cost of a case of mastitis in the UK
£200
what is the most significant area of financial loss in a respiratory disease outbreak?
weight loss
name 3 ongoing losses associated with an outbreak of respiratory disease in cattle
- reduced growth rates
- reduced carcase quality
- reduced milk yield
name 5 external/environmental factors that may compromise respiratory tract defences, permitting pathogens and/or opportunists to colonise respiratory tract leading to respiratory disease
- stress
- malnutrition
- dehydration
- dust
- ammonia
name 3 risk periods for suckler calves
- indoor calving
- housing at weaning
- housing for finishing
name 2 ways risk factors can lead to disease
- increase pathogen load
- compromise defences
name 3 ways to mitigate multiple sources as a risk factor for respiratory disease in cattle
- minimise number of sources
- establish long term relationships
- avoid markets/collection centres
name 2 ways to mitigate transport as a risk factor for respiratory disease in cattle
- minimise distances
- direct routes
name 2 reasons that transport is a major risk period for respiratory disease in cattle
- stressful
- coincides with other stressors
name 2 reasons large group sizes is a risk factor for respiratory disease in cattle
- more likely to encounter infected animals
- social stress
name 3 ways to mitigate large group sizes as a risk factor for respiratory disease in cattle
- <5 cows/pen if <8wks old
- <40 calves/pen if weaned calves
- minimise number of pens in same airspace
name 2 reasons mixed age groups is a risk factor for respiratory disease in cattle
- increases bullying, leading to social stress
- older calves act as a reservoir of infection for younger calves
name 3 ways to mitigate mixed age groups as a risk factor for respiratory disease in cattle
- tight calving pattern
- one calf crop/shed
- fill shed as quickly as possible
name 2 ways to mitigate group changes as a risk factor for respiratory disease in cattle
- group according to herd of origin
- minimise changes
name 4 ways to mitigate temperature as a risk factor for respiratory disease in cattle
- insulated roof panels
- protect from falling cold (calf jackets)
- clip backs (larger cattle)
- address damp, draught, ventilation and humidity
name 4 reasons poor airflow and humidity can be a risk factor for respiratory disease in cattle
- incr. pathogen survival
- incr. dust, ammonia, H2S
- compromise mucociliary escalator
- decr. UCT (heat stress in older animals)
what antibiotic is useful for treating respiratory disease in youngstock when Histophilus somni is involved?
Florfenicol
what antibiotic is the only macrolide with Mycoplasma bovis license?
(but 30% clinical isolates resistant)
Tulathromycin
how long after treating youngstock with respiratory disease should you phone the client?
24-48h
name the two licensed drugs for Mycoplasma bovis
- Tulathromycin
- Resflor (florfenicol + flunixin)
name the 5 respiratory pathogens that have a licensed monovalent vaccine?
- IBR
- BRSV
- BCoV
- D. viviparus
- M. haemolytica
are there any licensed cattle vaccines for maternal vaccination to reduce respiratory disease in calves?
no
name the disease
congestive heart failure;
due to hypoxic pulmonary vasoconstriction and remodelling;
mean pulmonary arterial pressure (mPAP) measured in bulls
high-altitude/brisket disease
are respiratory disease outbreaks more common in young stock or adult cattle?
young stock
name 4 ways to investigate nasal passage disease in cattle
- unilateral/bilateral
- discharge
- percussion
- radiography, endoscopy
name 4 differential diagnoses for nasal passage disease in cattle
- trauma
- foreign bodies
- infection
- neoplasia
what is the treatment for nasal passage disease in cattle
- prolonged antibiosis for infections
- lavage and drainage for sinusitis
name 3 clinical signs of larynx/pharynx disease in adult cattle
- stertor
- hypersalivation
- tachypnoea
name 4 ways to diagnose larynx/pharynx disease in adult cattle
- gag and torch
- auscultate/palpate larynx
- palpate retropharyngeal LNs
- radiography, u/s, endoscopy
name 2 treatments for larynx/pharynx disease in adult cattle
- broad spectrum abx if infected (amoxicillin, penicillin, streptomycin)
- dexamethasone if inflammation restricting airways
this is the most common cause of respiratory disease outbreaks in adult cattle
infectious bovine rhinotracheitis (IBR)
name 3 ways to diagnose IBR (infectious bovine rhinotracheitis) in adult cattle
- clinical signs (pyrexia, occulo-nasal discharge, coughing, tachypnoea)
- PCR on conjunctival swabs/BAL
- purulent tracheitis at post-mortem
name the 3 treatments for IBR (infectious bovine rhinotracheitis) in adult cattle
- NSAIDs
- abx if secondary infection suspected
- live intra-nasal vaccine
name the two main pathogens causing acute bacterial pneumonia in adult cattle
- Mannheimia haemolytica
- Pasteurella multocida
name the cause of respiratory disease in adult cattle
develops following incomplete recovery from pneumonia;
flare up of a chronic septic focus;
often after calving or stress;
T. pyogenes is main isolate
chronic suppurative pulmonary distress
name 5 clinical signs of chronic suppurative pulmonary disease in adult cattle
- dull with chronic weight loss
- intermittently febrile (39-39.5 C)
- milk production reduced by 25-50%
- tachypnoea and moist cough
- nasal discharge
what is the treatment for chronic suppurative pulmonary disease in adult cattle
prolonged abx treatment:
daily procaine penicillin for 6 weeks
(50% success rate)
what is the treatment for Dictyocaulus viviparous (lungworm/husk) in adult cattle
whole group treatment with anthelmintic
name the two main ‘alarm bells’ for Dictyocaulus viviparous (lungworm/husk) in adult cattle
grazing & coughing
name the cause of respiratory disease in adult cattle
sudden onset 1-2 weeks after moving to lush pature;
severe respiratory distress;
overgorging on alfalfa, rape, kale and turnip tops;
NO coughing, NORMAL rectal temp;
loud expiratory grunt, neck extended, reluctant to move, harsh crackles;
NO effective treatment
fog fever
name the cause of respiratory disease in adult cattle
allergic broncho-alveolitis;
housed cattle, mouldy hay;
sudden onset severe dyspnoea;
corticosteroids;
avoid mouldy hay
farmer’s lung
name the 3 most important causes of skin disease in cattle
- lice
- ringworm
- chorioptes
name the main cause of ringworm (dermatophytosis) in cattle
Trichophyton verrucosum
name 3 ways the spores causing dermatophytosis (ringworm) are transmitted
- clinical cases
- carrier animals
- fomites
what is the incubation period for ringworm
1 week
(to 4 weeks)
name the cattle skin disease
non-pruritic, alopecic lesions +/- broken hairs;
lesions raised, grey/white, powdery surface +/- exudation;
often roughly circular or oval (3-5cm) ;
calves: periorbital, ears, back
adults: thorax, limbs (udder)
dermatophytosis (ringworm)
how to diagnose dermatophytosis (ringworm)
hair plucks and skin scrapes
what is the treatment for dermatophytosis (ringworm)
topical: enilconazole (Imaverol)
is there a vaccination for ringworm?
yes: Ringvac
(two doses 10-14 days apart)
name the biting lice that affect cattle
(big round head)
Bovicola bovis
what is the diagnosis for lice on cattle
presence of lice and eggs
(differential diagnosis: mange)
name 3 pyrethroid pour-ons that can be used to treat lice in cattle
- Deltamethrin
- Alphacypermethrin 1.5%
- Permethrin 4%
name 4 types of mange (mites) that affect cattle
(less common than lice)
- Sarcoptes scabei
- Psoroptes ovis
- Chorioptes bovis
- Demodex
what is the most common mite affecting UK cattle?
surface mite, life cycle 2-3 weeks, lives off epidermal debris
Chorioptes bovis
(Chorioptic mange)
name the mite
zoonotic;
30% UK mange;
burrowing mite;
lifecycle 10-17 days
Sarcoptes scabei
(sarcoptic mange, scabies)
what is the treatment for mites in cattle (3 options)
- endectocide pour-on (ivermectin)
- endectocide injection
- permethrin pour-on
what causes viral papillomatosis (warts) in cattle?
Bovine papillomavirus
name the skin disease in cattle
photodynamic agent deposited in skin, irradiation leads to cell death;
non-pigmented areas with not much hair;
necrosis and sloughing
photo-sensitisation
what is the secondary disease of photo-sensitisation?
liver disease / jaundice
what plant causes photo-sensitisation in cattle?
St John’s Wort
(little yellow flowers)
name the skin disease of cattle based on clinical signs
high temp,
blue opacity of eyes,
mucopurulent inflammation of mucosa of eyes, URT, and mouth;
mucosal erosions - anywhere but mouth often affected;
sloughing of nasal planum;
death usually occurs within 5-10 days
Malignant catarrhal fever (MCF)
what is the treatment for malignant catarrhal fever (MCF)?
no treatment, animal should be euthanased
name the 3 forms of bovine sporadic leukosis
- juvenile lymphosarcoma
- thymic lymphosarcoma
- cutaneous lymphosarcoma
name the form of bovine sporadic leukosis (BSL)
acute onset aged 2wk-6mo;
generalised lymphadenopathy;
clinical signs vary with lesion location;
lymphocytosis often present;
always fatal
juvenile form BSL
name the form of bovine sporadic leukosis (BSL)
usually cattle 1-2y old;
affects cervical and/or intrathoracic thymus - so neck swelling not always a feature
thymic form BSL
name the form of bovine sporadic leukosis (BSL)
cutaneous plaques 1-5cm on the neck, back, flank, rump, and thighs;
onset can be very rapid;
initially raised lumps which become pale necrotic scabs;
local LN enlargement;
weight loss;
may also have/progress to viscera tumours
cutaneous form BSL
name the type of fly affecting cattle
notifiable in the UK;
adults lay eggs on skin, larvae hatch in 4 days and burrow into skin to overwinter in muscle;
subcutaneous nodules and cysts form along backs of cattle in spring, larvae then burst out and pupate to adults in soil
warble fly
name the 3 main causes of eye lesions in cattle in the UK
- new forest (IBKC)
- Listeria uveitis
- IBR
name the 2 main causes of eye lesions in sheep in the UK
- pink eye (IOKC)
- Listeria uveitis
name the eye disease in cattle
aka New Forest eye, pinkeye;
caused by Moraxella bovis;
endemics possible
Infectious Bovine Keratoconjunctivitis
(IBKC)
name 3 outcomes Infectious Bovine Keratoconjunctivitis
(IBKC) may lead to
- deep ulceration
- descmetocele
- rupture
name 3 treatment options for Infectious Bovine Keratoconjunctivitis
(IBKC)
- topical antibiosis (early cases only)
- subconjuntival injection (penicillin) - best option
- systemic (oxytetracycline LA or Florfenicol)
name 3 ways to reduce predisposing factors to control/prevent Infectious Bovine Keratoconjunctivitis
(IBKC)
- fly control
- adequate head space at feeders
- control dust/long vegetation
name the eye disease of cattle
aka Silage eye;
associated with Listeria monocytogenes and big bale silage;
bluish white corneal opacity spreading centrally;
white focal aggregations of fibrin
Listerial uveitis
what is the treatment for listerial uveitis
penicillin and dexamethasone
name the eye disease in cattle
herefords most common;
most >5y age;
long term sunlight exposure;
non-pigmented scleral, conjunctival, palpebral tissues;
UV light leads to neoplasia
ocular squamous cell carcinoma
what is the treatment for ocular squamous cell carcinoma in cattle
surgical removal
(enucleation)
name 3 ocular signs of infectious bovine rhinotracheitis
- conjunctival oedema
- 3rd eyelid partial prolapse
- ocular discharge
what vitamin deficiency can cause blindness, night blindness, papilloedema, and/or xerophthalmia
vitamin A deficiency
name the eye disease in sheep
aka pink eye;
more severe in ewes than lambs;
caused by Mycoplasma conjunctivae or Chlamydia psittaci;
4 stages of clinical signs ending in blindness and corneal ulceration
infectious ovine keratoconjunctivitis
(IOKC)
what is the treatment of infectious ovine keratoconjunctivitis
(IOKC) in ewes
single IM injection of Oxytet LA
(and NSAIDs for pain)
name the eye disease of sheep
adult hill sheep;
prolonged ingestion of bracken (Pteridium aquilinum);
progressive degeneration of the retinal neuroepithelium;
cilateral blindness of sheep over 2 years old;
hyper-reflectivity of tapeta;
no treatment
bright blindness
name the eye disease of sheep
common cause of traumatic keratitis in newborn lambs;
lower lid rolls inward;
keratoconjunctivitis and blepharospasm
congenital entropion
what are the 2 treatment for congenital entropion in sheep
- sub-conjunctival injection of abx (penicillin)
- application of Michel clips
what anaesthetic block must be given for a third eyelid flap procedure
auriculopalpebral block
(+ sedation and topical anaesthesia)
(where dorsal border of zygomatic arch meets base of ear)
how long to leave a third eyelid flap for?
2-3 weeks
name 2 indications for a third eyelid flap in cattle/sheep
- severe ulcer
- ruptured anterior chamber
name 4 indications for enucleation of cattle/sheep
- trauma
- globe rupture
- panophthalmitis
- tumour
what anaesthesia should be given to cattle/sheep for enucleation
- sedation
- 4 point retrobulbar block
(or Peterson block + local analgesia of eyelids)
name the 5 steps of an enucleation
- eyelids sutured together
- elliptical cut 2mm from eyelid margins
- blunt dissect between conjunctiva and eyelids
- section all muscular attachments close to sclera
- clamp and ligate optic nerve and vessels
name the major viral pathogen affecting cattle
Bovine Herpes Virus-1;
latent infection;
suspect if URT noise, hypersalivation, oculo-nasal discharge, conuunctivitis, corneal oedema
Infectious Bovine Rhinotracheitis (IBR)
name the major viral pathogen affecting cattle
paramyxovirus;
necrotising bronchiolitis, interstitial pneumonia;
caudo-dorsal lobe emphysema
Bovine Respiratory Syncytial Virus (BRSV)
name the major viral pathogen affecting cattle
paramyxovirus;
mild bronchiolitis;
compromises monocytes & alveolar macrophage function
Parainfluenza virus type 3 (PI3)
name the major viral pathogen affecting cattle
pestivirus;
immunosuppressive;
presence of persistently infected calves a major risk factor for BRD
Bovine Viral Diarrhoea (BVD)
name the 3 major viral pathogens causing respiratory disease in cattle
- IBR
- BRSV
- PI3
name the major bacterial pathogen affecting cattle
gram neg, small rod, facultative anaerobe;
necrotising fibrinous pleuropneumonia;
12 capsular serotypes (A1 most important);
commensal - switch to pathogenic phenotype may be density dependent;
shipping fever (7-14d after transport)
Mannheimia haemolytica
name the major bacterial pathogen affecting cattle
gram neg, rod/coccoid rod, facultative anaerobe;
necrotising fibrinous pleuropneumonia;
commensal (zoonotic?);
switch to pathogenic phenotype unknown
Pasteurella multocida
name the major bacterial pathogen affecting cattle
gram neg, small rod, facultative anaerobe;
range of pathogenicity (commensal to septicaemic);
myocarditis, pleurisy, bronchopneumonia, polyarthritis;
thrombo-embolic meningoencephalitis (TEME)
Histophilus somni
name the major bacterial pathogen affecting cattle
lacks a cell wall (beta-lactam abx useless);
small, pleomorphic, facultative anaerobe;
exudative bronchopneumonia;
survives intra-cellularly;
experimental infection mild but synergistic with other pathogens leads to range of clinical signs;
can be transmitted through milk
Mycoplasma bovis
name the 4 major bacterial pathogens causing respiratory disease in cattle
- Mannheimia haemolytica
- Pasteurella multocida
- Histophilus somni
- Mycoplasma bovis
what is the minimum number of ACUTELY UNWELL animals you should sample when trying to diagnose cause of respiratory disease outbreaks
at least 5 animals
name the sample that can be taken during a respiratory disease outbreak
most expensive, easy to take;
2 samples 2 weeks apart (rising titre);
no results for at least 3 weeks and no abx sensitivity data;
only way of assessing BVD involvement
blood (serum)
name the sample that can be taken during a respiratory disease outbreak
easy to take;
IBR only;
PCR;
results in 24h
conjunctival swabs
name the sample that can be taken during a respiratory disease outbreak
easy to take;
need long guarded swabs;
onle samples URT;
will sample commensals;
submit for PCR for IBR/RSV/PI3 & culture/sensitivity;
results from 24h to 3d
(do NOT use wooden swabs)
nasopharyngeal swab
name the sample that can be taken during a respiratory disease outbreak
slighlty harder to take;
samples LRT;
less likely to contain commensals;
submit for PCR for IBR/RSV/PI3, culture & sensitivity, cytology if lungworm suspected;
results from 24h to 3d
broncho-alveolar lavage
name the treatment used for bovine respiratory disease
mucolytic, improves airway potency
Bromhexine
what is the most important drug to give to cattle with respiratory disease?
NSAID
what vaccine can be given to cattle in a respiratory disease outbreak?
onset immunity 4d
live intra-nasal IBR vaccine
what two oral drugs are licensed in the UK for prevention of respiratory disease?
Tylosin and Tilmicosin
what 2 classes of antibiotics should ONLY be used if indicated by C&S
- fluoroquinolones
- 3rd/4th gen cephalosporins