Cattle 3 Flashcards
What questions to ask on the phone for a calving call and on arrival
○ Is she a heifer/ how many calves has she had before
○ How long has she been presenting those signs
○ What have you tried with her
○ Why do you think she is calving and what makes it different
On arrival
○ Where is the cow
○ Has anything changed since we last spoke
○ Previous history of the cow
Schistosomus reflexus what is it, how generally present, cause, treatment and future for cow
§ Generally come out guts and viscera first or head and legs first
□ If 2 front feet and 2 back feet present -> may think it is twins so try to push and pull but nothing happening
Cause - don’t know - failure of body to zip up at the beginning of gestation
What do you do now
○ Kill the calf humanely asap -> captive bolt, lethabarb
○ Check cow for possible trauma -> foot through uterus?
○ Check for a twin
- Should we cull her?
○ Not a reason to cull the cow - sporadic
○ If a good cow then no, but if a bad cow then maybe the tipping point
What are the 4 main supplementary tests for diagnosing skin disease
- Swabs for microbiology
- Skin scrapings
- Biopsy or impression smears
- Haematology/biochemistry
Ringowrm significance, what common in, findings, diagnosis and treatment
○ Zoonotic - especially for young/old - not much of an issue
○ Fungal and common
○ Esp in young animals in close contact
○ Findings - Grey, circular crusts… may coalesce
○ Diagnose - skin scraping show hyphae/spores
○ Treatment - Often resolve spontaneously but treatment sometimes requested (iodine - twice a day for 2 weeks)
Papillomatosis appearance, when issue, diagnosis, treatment and control/prevention
○ Appearance is highly variable
§ Proliferative, hairless, on head, teats, penis
○ Only an issue if in a spot where interfering with normal processes such as teat, eye, penis, show animals
○ Diagnosis on appearance
○ Treatment not usually required as generally go away by itself
§ Excision, autogenous vaccine
○ Control/prevention - immunotherapy (BCG)
Dermatophilosis cause, presentation and treatment
○ Dermatophilus congolensis
○ Damaged, broken or macerated skin - diffuse
○ Sporadic in temperate areas - warm climates
○ Scabs are tenacious - hair growing through
○ Can become infected with other bacteria
○ Not usually pruritic - unlike manage
○ Treatment - antibiotics (penicillin, tetracycline) and predisposing factors
What are the 3 main lice of cattle, generally what animals present on and treatment
pediculosis
○ Sucking lice - haematopinus eurysternus, linognathus vituli
○ Biting lice - bovicola (Damalinia) bovis
○ Host specific with site preferences
○ Generally underlying reason ->
○ Esp in young animals, often “secondary”
○ Treatment - spray, pour-on, injection in autumn/winter
Mange mites how host specific, diagnosis, the 3 main types in Australia and what do they lead to
○ Not as species specific ○ Diagnose - via skin scraping a. Chorioptic (Chorioptes bovis) § Ugly but often not itchy - thickened wrinkles skin § Bad cases can get very itchy b. Demodectic (demodex bovis) § Species specific § Little irritation.. Brisket, neck, withers § Often asymptomatic - not usually diagnosed clinically c. Ear mites (raillietia auris) § Otitis externa § Unsure on whether pathogenic
What are the 2 main exotic mites and what they do to the cattle
a. Sarcoptic (sarcoptes scabei var bovis) § Fairly host specific § Annoying, brisket, neck and groin b. Psoroptic (psoroptes ovis) § Primarily a parasite of sheep § Notifiable in Australia § Can lead to high sensitivity
What are the 3 main ticks of cattle
1) boophilus microplus
2) haemaphysalis longicornis (NZ cattle tick)
3) ixodes holocyclus (paralysis tick)
Boophilus microplus lifecycle, significance and 3 control strategies
§ One host tick (3 weeks on host, 1 month egg laying)
§ Heavy infestations > “tick worry” - they hurt, annoyed, depressed
§ Important vector of disease
□ Babesiosis and anaplasmosis - diseases of the blood that will kill, anaemia, decrease production
® Real issue when naïve cattle are exposed to ticks -> DEATH
§ Control
1. Chemical control of ticks
2. Resistance of cattle (bod indicus)
3. Vaccine (expensive, repeated)
Haemaphysalis longicornis and ixodes holocyclus lifecycle, where found and effect
Haemaphysalis longicornis (NZ cattle tick)
§ Three host tick
§ Found in relatively low numbers in Australia
□ Queensland, NSW, Victoria
§ Less significant
Ixodes holocyclus (paralysis tick)
§ Can cause ascending paralysis, esp in calves
- Sporadic, in wetter coastal regions of eastern Australia
Photosensitive dermatitis what are the primary causes
- Exogenous PDAs absorbed
® Ingested, then PDAs circulate in periphery
® Pale, hairless skin then exposed to UV light
® UV light alters PDA to cause cellular damage - Plants - e.g. St John/s Wort, Brassica spp
® Esp. immature plants, infected with fungi - Drugs - phenothiazine, corticosteroids
Photosensitive dermatitis secondary cause pathogenesis
- Chlorophyll converted to phytoporphyrin
® Phytoporphyrin previously known as phylloerythrin
® Produced by bacteria in the rumen
® Usually conjugated in liver and excreted in the bile - Reduced excretion in bile allows build-up
- Hepatotoxins impair hepatobiliary excretion
® Sporidesmin (pithomyces chartarum), lantana - leads to fascial eczema
Photosensitive dermatitis clinical signs and what can lead to with result
○ Clinical signs vary in severity
§ Behavioural -> may not see lesions but hypersensitive skin
§ Physical -> sloughing, bleeding, ulcerations
- found underside of tongue, lateral aspect of teat (problems when milking), backs, nose
- Acute bovine liver disease
® Autumn or early winter
® Mortality 10-20%
® Pyrexia, depression, milk drop, severe photo
Facial eczema how occurs, how common, where, pathogenesis
- a disease manifested via secondary photosensitisation
○ Quite common and serious in Australia (Gippsland) and NZ
○ Pithomyces chartarum grows on pasture
§ Dead lead litter in warm, humid weather
§ Sporulation after 4 days of >12 degrees with moisture at ground level
○ Fungal spores contain sporidesmin -> necrosis of bile ducts
Facial eczema clinical signs, diagnosis and treatment
○ Typical photosensitisation signs - Signs occur 10-14 days after exposure
○ Diagnosis
§ Clinical signs and epidemiology - multiple animals in late summer early autumn
§ Serum GGT >70IU/L mild, >300 moderate, >700 severe - may need to cull if severe
○ Treatment
§ Protect from sunlight - lock in a shed (will not stay there willingly)
§ Anti-inflammatories (and antibiotics) as support
§ Zinc is not effective after exposure or once clinical signs become apparent
Facial eczema what are the 3 main control methods
1) Monitor paddocks by spore counts >100,000/g is dangerous (less if grazing harder)
- Find information on websites such as dairy Australia
- Farms can do there on spore counts
2) Provide zine early (prior to exposure)
- Zn sulphate in water using automated dispensers - cows can taste, will choose to drink different water if available
- Zn oxide as an oral drench - everyday
- Metallic Zn oral bullets (FaceGuard in NZ)
- Zn toxicity is a significant danger
® ↓ therapeutic margin
® Gastroenteritis, anorexia; ↓milk production
3) Pasture fungicides available in NZ
Squamous cell carcinoma how common location and character
○ Common ○ Esp in white skin of cows § Muco-cutaneous junctions - eyes, vulva, anus § Along back or on udder ○ Locally invasive, locally metastatic
Ocular carcinoma how common, where present, treatment options
○ Common in beef and dairy cows
○ Eye pigment. Sunlight, viral agents
○ On eyeball or third eyelid
○ May regress but may also invade or metastasize (locally)
Several treatment options
§ Surgery (easy with third eyelid), cryotherapy, radiotherapy (not common)
Ocular carcinoma when salvage slaughter is important
§ Illegal to send cattle with malignant tumors of the eye larger than 2cm to saleyards
§ If not bleeding or discharging up to 2cm may be sold
§ If between 2-3cm go to abattoir at owners risk of non-payment
§ If send large tumors to abattoirs or saleyards may lead to animal cruelty fines
Cutaneous angiomatosis and lymphosarcoma what are they, location, results
Cutaneous Angiomatosis ○ Usually on back or flanks ○ Often only noticed due to trauma -> LOTS OF BLOOD -> tie off the bleeder Cutaneous lymphosarcoma ○ Uncommon ○ A form of sporadic bovine leukosis § Also occurs as multicentric and thymic forms ○ Usually in younger animals (<3 years)
What are the 5 main skin diseases of calves
- Inherited epidermal dysplasia aka. “baldy calf syndrome”
- Neonatal alopecia
- Inherited congenital hypotrichosis
- Iodine deficiency
- Curly coated cardiomyopathy
Baldy calf syndrome cause, effect and treatment
○ Inherited as autosomal recessive trait
○ Progressive changes in skin after birth
§ Patches of alopecia
§ Overgrown hooves
§ Also excessive lacrimation, poor appetite
- May respond to Zn supplementation
Pseudo-lumpy skin disease what differential for, cause, effect and treatment
○ Differential for lumpy skin disease (exotic -> deep lesions in the skin) ○ Bovine herpes virus type 2 § Also causes bovine herpes mammillitis § Multiple firm cutaneous nodules § Resolve spontaneously
Subcutaneous emphysema what occurs and treatment
○ Traumatic, can suck air into subcutaneous tissues
○ Treatment - penicillin (just in case), will resolve by itself
Enzootic bovine leukosis (EBL) cause, significance, presence in australia and risk factors
- Infectious - retrovirus
- An important disease of cattle - notifiable
○ Decrease prod, restrictions (trade, semen sales, milk etc) - Eradicated from Australian DAIRY herd through regular testing
- Beef bulls introduced to dairy herds should be EBL tested!
Risk factors - Older animals (<5)
- Less than 5% infected animals show clinical signs of lymphosarcoma
○ Approx. 30% develop non-neoplastic lymphocytosis
Enzootic bovine leukosis clinical signs, transmission and diagnosis
Clinical signs - progressive - weight loss, decrease production (peracute if heart/adrenals involved = catastrophic events)
Transmission - Vertical and horizontal transmission - instruments contaminated with blood
Diagnosis - serology or milk vat tests
Sporadic enzootic bovine leukosis cause, how common, 3 types and diagnosis
- Not related to BLV
- Uncommon but fatal
- Cause unknown - genetics
- More likely to see this in practice
- Young animals
- Sporadic
Types
1. Juvenile, multicentric form: symmetrical LN enlargement, weight loss, death
2. Thymic form: mass around thoracic inlet, dysphagia, resp distress
3. Cutaneous form (rarest): grey/white hyperkeratotic plaques -sometimes appears to get better, typically recurs and animals diet due to infiltration of other organs
Diagnosis - Presence of leukaemia, anaemia, serology to rule out EBL
Symmetry of the head what looking for and differentials
○ Drooping ears
§ Differentials - otitis external, listeriosis
○ Swelling (unilateral vs bilateral)
§ Differentials - abscess, actinomycosis, tumours
○ Excessive licking or chewing, irritability
§ Differentials - hypomagnesaemia, lead poisoning
Listeriosis cause and important characteristics of organism and significance
- Listeria monocytogenes
- Can grow in temps 3-45 degrees, pH 5.6-9.6
- Can survive environmental conditions for long periods (hay, silage, faeces, straw)
Can live and multiple inside
macrophages
ZOONOSIS - food poisoning and abortion in humans
Listeriosis clinical signs and treatment
Clinical signs
- Encephalitis, abortion, iritis in cattle, paralysis
- Unilateral facial paralysis - no menace reflex, droopy ear, tongue weakness, depressed, inappetant
- Progresses to recumbency
- Depends on which nerves the bacteria infiltrates within the head
Treatment
- Eliminate infection (Ab’s - penicillins), supportive care
Otitis externa how common, mite involved and treatment
- Especially old hot northern cattle, sporadic in temperate env
- Raillitia mites - importance unknown
Treatment- Antibiotics
- Flush
- drain
Otitis media spread, result, clinical signs and treatment
- Eustacian tube or homogenous spread
- Exudate, pressure increase, tympanic rupture
Clinical signs - Tilted head - affected ear down, milk circling - dirft towards affected side, purulent discharge
- Droopy ear - involvement of facial nerve
Treatment - Antibiotics - broad spectrum for several weeks
Anaphylaxis general cause, clinical signs and treatment
- Generally in response to something you or farmer has given them -> vaccines, blood transfusion, LA corticosteroids
Clinical signs - Generalised oedema with respiratory signs, dyspnoea, cyanosis, death
Treatment - Need adrenalin quickly!!
What are the 4 main reasons for licking of chewing
- Foreign body
- Phosphorus deficiency (pica, lactating beef cattle)
- Ketosis (chewing) - nervous ketosis as a result of poor nutrition in late pregnancy
- BSE (bovine spongiform encephalopthy) (nose licking, flehmen, head tossing)
When checking the eye and eyelids in cattle what are you looking for
- Discharges - uni or bi-lateral
- Sunken eyes - hydration
- Protrusive eyes
- Movements (nystagmus)
- Menace reflex - slight/motor function
- Pupillary light reflex (optic vs oculomotor vs central) - dark env, bright light source
- Conjunctiva and eyelids - colour, lesions and pain
- Cornea (ulcers, opacity, vascularisation, scarring)
- Anterior chamber (hypopyon)
Eye lesions what are the 3 main conditions that cause this
1) Infectious bovine keratoconjunctivitis (pink eye, IBK)
2) Squamous cell carcinoma (cancer eye)
3) Inflammation associated with systemic disease
○ Bovine herpesvirus type 1 (infectious bovine rhinotrachetitis)
○ Malignant catarrhal fever
○ Septicaemia
○ Anaphylaxis
Bovine herpes virus what are the 2 forms, predisposed for and clinical signs
- Highly infectious - discussed under respiratory
○ Genital form - vulvovaginitis
○ Respiratory form - mild respiratory, profuse oculo-nasal discharge - Predisposes to more severe respiratory disease (enzootic pneum, pneum pasteurellosis)
○ Calves: severe systemic disease in neonates, respiratory dz and diarrhoea - Nasal signs as well as occular signs (white necrotic plaques)
Malignant catarrhal fever main presentation, 3 forms, clinical signs, treatment and what need to differentiate from
- Acute, fatal, sporadic (1-3y) - contact with sheep
3 forms
○ Head/eye - most common and described below
○ Peracute
○ Milk
Clinical signs - Conjunctivitis, copious ocular and mucopurulent nasal discharge, eyelid oedema
- corneal opacity starts at the limbus and progresses centrally sometimes - pathognomonic
- Also severe mouth lesions, nose lesions and severe pyrexia (fragile MMs)
Treatment - Untreatable, euthanasia
Differentiate from - exotic vesicular disease and BVD
