Cattle

Question 1

features of highly fertile beef herd - calving pattern, female calve in first cycle, calving rate, age of heifers, heifer dystocia

Answer 1

• Calving pattern 8 weeks in cows and 6 weeks in heifers
• 70% of females calve in first cycle
• calving rate > 95%
• use highly fertile high serving capacity bulls
• heifers calve down as 2 year old
• heifer dystocia rate < 5%
• high heifer retention rate enabling cows to be sold at 8 years old having reared their 6th calf

Question 2

Heifer critical mating weight what is it and how old are heifers at joining

Answer 2

• Puberty is related to body weight as well as age
• CMW definition: 84% conceive in 6 weeks
• Will vary with breed and herd
• Most breeds start cycling at about 52% mature BW
• Typical benchmark is 60-65% of average mature BW for the herd
• Growth rate about 1kg per day
  How old are heifers at joining
• Aim to calve at 2 years so oldest will be 15-16 months old, later clavers 13-14months
• THEREFORE later calving heifers need to achieve CMW at an earlier age - WHY CALVING PATTERN IS SO IMPORTANT

Question 3

Heifer weaning when to wean and how related to energy in the paddock and the mothers nutrition - BEEF

Answer 3

When to wean
- Minimum Age = 100 days from when the last calf born
- Maximum Age = 6 months, depending on season and available feed
○ Why 6 months? At 6 months some bulls will be reproductively available
- If Cow condition drops to 2.5
Energy
- Certain amount of energy in the paddock
- Feed in paddock
○ 1. turn feed into calf OR 2. turn feed into milk THEN turn milk into calf
- At some point it is more efficient to turn the energy directly into the calf -> WANT TO WEAN AS SOON AS POSSIBLE
- Also FOR THE MOTHER
○ Dam eat feeds
§ Some feed used for maintenance
§ Some feed turn into milk
§ Excess feed stored as fat -> when wean move to this
○ Therefore in droughts “early weaning can be a good strategy”

Question 4

Selection of heifers for joining how much retain of heifers, which age group better and 5 reasons whyv

Answer 4

• Herds often retain 40-50% of heifers
• This is equivalent to 20 -25% of herd size
• Retaining more heifers will lead to a younger herd- BETTER
  1. Cow value declines after 6-7 years
  2. Bodyweight peaks at 7-8 years
  3. Weaning weights of calves declines in older cows
  4. Older cows are more likely to die
  ○ Grass Tetany
  ○ Cancers
  5. More flexibility to cull for genetic gain

Question 5

Spermatogenesis overview what does it consist of and the cycle of the seminiferous epithelium, how long does it take

Answer 5

• Spermatocytogenesis ( = Phases one and two, or Proliferation and Meiosis)• Spermiogenesis (= Phase three, or Differentiation)
• Note cellular bridges allowing cells to develop as cohorts
Cycle of the Seminiferous Epithelium
- This is a useful analogy to help understand the cycle of the seminiferous epithelium
- Each 12 month cycle has two stages (semesters)
- It takes 4 cycles (years) to complete the process
○ Cell division
○ DNA packaging
○ Add a motor and energy cells
○ Switch it on

Question 6

Toxic sperm how occur and type of defect formed

Answer 6

• After fertilization, the DNA must be carefully unpacked
  ○ If the packing is done poorly, it will be unpacked poorly and the fertilized egg will die
• Eggs can only be fertilized once
  ○ “Uncompensible defects”
  § Minor insults can be worse than major ones -> major cannot get to egg but minor can get to egg BUT NOT FERTILISE
  § Dead sperm can be compensated for by other sperm - compensible defect
  § Toxic Sperm waste eggs - cannot be changed with increasing sperm

Question 7

List some things that can cause sperm abnormalities, how long do they last and how do we aviod toxic sperm

Answer 7

What can cause sperm abnormalities 
- Transport, Diet
- Temperature, Lameness
- disease, stress, toxins
How long do they last 
- 30-40 days later it may then become apparent 
How do we avoid Toxic Sperm ?
- Know the history
- Own the bull for 70 days
- Don’t use a sick or injured bull for at least 70 days

Question 8

What are the 4 main things you should vaccinate bulls against

Answer 8

1. 5 in 1 (Clostridialdiseases)
2. Leptospirosis
3. Vibriosis
4. Pestivirus

Question 9

Veterinary bull breeding soundness evaluation (VBBSE) what is it, what does it do and the 5 components it reports

Answer 9

• a protocol developed by the ACV to be a relatively quick and economic procedure for screening bulls prior to sale or use.
• not a guarantee - NEED TO IDENTIFY THE BULL
• Screen out “high risk” rather than screen out “Infertile”
• Uniform accepted standards
  The 5 components are reported:
  1. Scrotal circumference - score 1-5
  2. General Physical Examination
  3. Crush Side Semen Evaluation
  4. Serving Ability Testing
  5. Semen Morphology Testing

Question 10

Physical examination for Veterinary bull breeding soundness evaluation (VBBSE) what are the 8 things involved and what looking for

Answer 10

1. Identify the bull
2. Condition score
3. Check the eyes - squamous cell carcinomas, vision impairment
4. Sheath structure
5. Examine the hooves - scissor claw, curled tow, worn claw, sand cracks
6. Examine leg structure and conformation - posty leg, sickly hock, degenerative joint disease
7. Examine gait
8. Reproductive Organs

Question 11

Crush side semen evaluation for Veterinary bull breeding soundness evaluation (VBBSE) what are the standards for the semen to pass

Answer 11

• Density of 1 or more
  ○ 200 sperm per 100x field under a cover slip
• Absence of blood or urine staining
• Absence of flocculant material and large numbers of pus cells
• Percent progressively motile -> actively moving forward
  ○ Tick – 60% +
  ○ Pass – 30% ‐ 59%
  ○ Fail ‐ < 30%

Question 12

Sperm morphology testing for Veterinary bull breeding soundness evaluation (VBBSE) how occurs, what identify and what need for AI and natural mating

Answer 12

• 8 drops of semen into a vial of buffered formol saline and send to lab
• Easy
• Identifies some permanent conditions
• Identifies some transient conditions
• Compensable vs non‐compensable defects
• Should have 70% normal sperm for AI
• 50%‐70% normal sperm ok for paddock mating
• Provided that
  ○ Not more than 20% uncompensable
  ○ Nor more than 30% of other individual abnormalities

Question 13

Contagious mastitis pathogens when spread and list 4 main ones, do they respond to treatment

Answer 13

• Spread at milking time
  1. Staph aureus
  § Responds well to treatment
  2. Strep agalactiae
  strep doesn’t respond as well to treatment
  3. Strep dysgalactiae
  4. Mycoplasma
  § Not as common but if have an outbreak highly contagious throughout the herds and highly problematic

Question 14

Environmental mastitis pathogens how spread and list 5 important ones

Answer 14

• Spread via environment
  ○ Paddocks, mud, faeces, calving pads, bedding, tracks
  1. Strep uberis
  2. E. coli
  § Generally highly clinical, gangrenous, toxic - depending on virulence factors
  3. Strep Dysgalactiae
  4. Pesudomonas
  § Very nasty cause again - highly toxic clinical signs
  5. A. pyogenes, Nocardia

Question 15

Name 4 management risk and pathogen risk factors for mastitis

Answer 15

management
1. Environment - mud and faecal contamination
2. Seasonal conditions - heat, humidity, wet and muddy conditions
3. Milking practices - hygiene, stress, machine issues - IMPORTANT - EXAM
4. Existing prevalence in herd
Pathogen
1. Viability in environment
2. Virulence factors - colonisation of duct, adhere to mammary gland
3. Toxins - E. coli and Staph aureus
4. Antibiotic resistance - large problem with herd level conditions especially with staph - why may need to cull cow

Question 16

ICCC what cells normally present, normal count, when increase

Answer 16

• Somatic cells are present in normal milk
• Epithelial cells and mononuclear leukocytes
• Usually in the order of 100,000 cells per mL
  INCREASE
• after calving (fall below 300,000 within 5 days)
• end of lactation
• Infection - On average 3.8 times higher than non-infected cow - Over 250,000 cells per mL for a 4 quarter sample suggests infection in at least one quarter - Cow with one count over 250,000 cells/ml, consider infected for entire lactation

Question 17

BMCC how used when should seek advice and production relation

Answer 17

Somatic cell count taken from bulk tank
- Used to form payment scales by milk factories
- Premium paid if milk produced under 200,000 or 250,000 cells/mL (depending on factory)
- Severe penalties if milk produced over 600,000 or 750,000 cells/mL depending on factor but considered poor if >400,000
- Should seek advice if:
○ Over 250,000 for 6 months
○ Receive penalty payment
Production
○ If BMCC increasing, production will be decreasing
○ 2.5% for every 100,000 above 200,000 cells/mL

Question 18

Antimicrobials for mastitis, what gets higher cure rate, which pathogens respond to treatment when and if no response what can you do

Answer 18

• Combination of parenteral and intramammary may result in higher cure rate
• Cure rates are dependent on pathogen
  ○ Staph aureus poor during lactation
  ○ Strep agalactiae very good
  ○ Strep uberis variable - can be difficult to cure
  If no response to treatment
• Treat for longer
• Try different antibiotic regime - culture
• Dry off quarter
• Chemically dry off quarter - infusing copper sulphate
• Dry off cow - DCT
• Cull

Question 19

Gangrenous mastits treatment options

Answer 19

• If lost sensation in that teat -> just remove the teat
• Systemic infection so need to treat systemically
  ○ IV - antibiotic and anti-inflammatory and possible IV fluids
  Another infected quarter -> give oxytocin -> promotes cow to let down milk

Question 20

Dry cow management how long, why done and the 2 types

Answer 20

• Minimum of 6 weeks required to allow udder tissue to regenerate
• With no dry period milk production will be reduced in following lactation (seeing contray evidence to this fact)
• A keratin teat plug seals teat canal at the start of dry period -> sturdier than other seal throughout lactating
  ○ Formation of keratin plug aided by DCT (dry cow therapy)
  1) antibiotic
  2) teat sealant- physical barrier

Question 21

List the 7 ways to manage mastitis

Answer 21

1) monitoring for mastitis via milk cultures, ICCC, BMCC, rapid mastitis test, NAGase test
2) treating clinical and subclinical infection
3) Looking at milking machine for faults
4) looking at milking technique for faults
5) scoring teat condition to see if that an issue
6) dry cow therapy - how conducted does it need to change
7) CULL COWS - with 3 or more clinical cases in lactation - not a long term fix

Question 22

Staph aureus causing mastitis reservoir, spread, presentation, treatment how easy and when

Answer 22

• Reservoir - infected udders and skin of teats (Teat end damage)
• Spread at milking by contaminated milk - all milking cows susceptible (esp. with teat sores/teat end damage)
• Found on liners 6 to 8 cows after an infected cow is milked
  Presentation
• Persistent sub-clinical infection generally but anything from that to sub-acute gangrenous
  Treatment
• Very difficult to cure with antimicrobials
• Very difficult to cure during lactation - dry cow therapy important - gives higher cure rates
• Resistant to many antibiotics
• Best results with young newly infected cattle

Question 23

Strep agalactiae causing mastitis characteristics, presentation and treatment

Answer 23

Obligate parasite, however can survive on milking machines, milker’s hands and clothes
- VERY RAPID SPREAD
- Infected cows shed very large numbers of bacteria
Presentation
- Causes very high rate of clinical mastitis
- Causes sub-clinical infections as well
- Can cause plate count failure
Treatment
- usually very effective during lactation - Penicillin sensitive
- DCT will cure up to 100% of infections

Question 24

Mycoplasma spread and main issues

Answer 24

• Spreads very rapidly from cow to cow
• Hard to culture -> need specialised culture
• Milking hygiene problems are risk factors
• Response to treatment very poor
• Often destroys milk production in cows
  ○ Often need to cull up to 75% of cows infected

Question 25

Strep uberis causing mastitis where found, factors that increase infection and presentation

Answer 25

- The leading cause of clinical and subclinical mastitis in Australia - Found in all areas of the cow's environment including muddy and faecal contaminated areas - Shed in the faeces of infected cows (can survive up to 2 weeks in manure/mud) - Putting machines on WET and/or DIRTY/MUDDY teat will increase incidence Presentation - Usually causes CLINICAL mastitis and can have very high incidence rates on farms - May cause BMCC penalties in early lactation - Some infection become chronic

Question 26

Treatment options for strep uberis mastitis

Answer 26

- Treat early ○ Refractor cases are very difficult to treat ○ Some strains more resistant to treatment -> do sensitivity testing - Treat cases aggressively based on sensitivity - Combination of intramammary and parenteral antibiotics needed

Question 27

Coliform mastitis which organism is most common, how infection occur, which cows most at risk and how disease occurs

Answer 27

- E.coli most common - Teat skin is contaminated in the environment - Infection may occur any time including milking High risk - around time of calving - Induced cows, or those suffering milk fever How occurs - Most infections localised in teat sinus, disease is caused by toxins - Toxins can cause serious systemic disease

Question 28

Treatment and control of coliform mastitis

Answer 28

- Mild cases may be treated by frequent stripping of quarter with the air of oxytocin - More severe cases systemic antibiotic, anti-inflammatory and fluid therapy - aggressive Control similar to strep uberis - hygiene

Question 29

Pseudomonas aerguinosa mastitis where found, presentation and treatment

Answer 29

- Isolate from water supplies, including rubber hoses - Contamination usually in the dairy ○ Too much water on teats ○ Water contamination of intramammary preparations and DCT - Very sick cows - often die ○ No antibiotics registered for use in cattle have efficacy against this bacteria

Question 30

Condition score dairy cattle, what is the numbering, important numbers and how to score

Answer 30

``` - Dairy Cattle score 1-8 in Australia ○ But very few 1,2,7,8 so in practical terms scores are between 3 and 6 - thin 3 fat 5 - 2-step “hands-off” scoring method only takes seconds 1. Look closely at area between tail and pins a. deeply sunken -> 2. are pins hollow -> yes - 3, no - 2.5 b. suken -> 2. backbone -> bumpy 4, flat 4.5 c. slightly sunken -> 2. depression between hip and pin -> Up-shape - 5, shallow - 5.5, flat - 6 d. filled in (same as slightly sunken) ```

Question 31

Acute septic metritis (puerperal metritis) what does severity depend on, clinical signs, treatment and a major risk factor for what

Answer 31

- Severity of infection depends on immune system, BCS of cow, nutrition, stress, bacterial species etc … - Clinical signs ○ Infection starts to have systemic effects ○ High temp, depressed, foul smelling redish colored uterine fluid +/- membranes Treatment ○ Controversial - many animals don’t die! ○ RFM – if the cow is not “sick” (pyrexic) wait 5-7 days ○ Manual removal – gently – stop if blood ○ My view – pessary always; parenteral antibiotics (alamycin) if pyrexic. § Pessaries -> antibiotic foam Metritis is a big risk factor for endometritis

Question 32

Endometritis define, clinical signs and list some bacterial causes

Answer 32

- Inflammation of the endometrial lining of the uterus without systemic signs, associated with chronic postpartum infection of the uterus with pathogenic bacteria - normal 90% of cows HOWEVER if Persist beyond 3 wks – endometritis Clinical signs ○ White discharge that DOESN'T SMELL ○ Cows are not sick ○ Causes lowered fertility if it persists Causes ○ Arcanobacter pyogenes, Fusobacterium synergistic ○ Pseudomonas, E coli, Streptococcus,Staphylococcus, ○ clostridia - gangrenous

Question 33

What are the 4 ways to treat ovarian cyst which respond well and which dont

Answer 33

1. Manual rupture ○ relatively low recovery rate ○ risk of ovarian haemorrhages and adhesions. 2. GnRH intramuscularly ○ causes the release of LH and luteinisation of the cysts (not ovulation) ○ Most cows that respond come into oestrus 18 - 23 days after treatment. 3. Progesterone (P4) - Follicular cysts may best be treated using a P4 releasing device to deprive the cyst of LH. This treatment will stop nymphomania behaviour immediately. In many cases, after removal, cycling continues normally. 4. Ovsynch program + P4 device Most successful unless 6 months or more then don't respond well

Question 34

Pregnancy diagnosis What are the 4 main ways to do it and from what age can start

Answer 34

1) rectal palpation - from 6-8 weeks 2) ultrasound linear - from 4 to 16 weeks 3) sector scanning - 5-16 weeks (not empties) 4) blood or milk tests - don't age the pregnancy

Question 35

What are the 6 important reproductive indexes

Answer 35

1) Submission Rate ○ % cows submitted in first 21 (or 30) days 2) Conception Rate ○ % cow pregnant per 100 inseminations 3) Pregnancy Rate ○ % of the herd pregnant after a given time 4) 6 week in calf rate ○ % of the herd pregnant after 6 weeks of joining in s seasonal or split calving herd 5) 100 day in calf rate ○ % of the herd pregnant within 100 days of calving in a year round calving herd 6) Empty rate ○ % herd empty (after a given no of weeks – 12or 20)

Question 36

What is the normal tempertaure, HR, RR and rumen contraction rate

Answer 36

Temp - 38.5 - 39.2 degrees Celsius HR - 60-80 with no murmurs or arrhythmias. >150 = poor prognosis. Rumen contraction rate is one every 30-90 seconds

Question 37

Udder impetigo what is it, presentation,, spread, zoonosis and treatment

Answer 37

- Staph aureus infection of the teat base and udder - Pustules are 2-4mm in diameter - Spread during milking and a large portion of herd may be infected - Can serve as source of bacteria for mastitis infections - ZOONOSIS - painful boils - Control with teat disinfection

Question 38

Hydrops how common the 2 types and treatment

Answer 38

- Not very common - Distention due to uterine issues not abdominal issue 1) hydrallantois 2) hydramnios Treatment 1. Termination of pregnancy § Corticosteroids, prostaglandins -> want to calf within 24-48 hours not 1 week □ Dystocias are common as not ready to calf at this point 2. Caesarean section § With supportive treatment § Tap the fluid out SLOWLY (over hours) - body has time to compensate the loss in blood pressure - Generally the cow is then milked through and then culled before next season

Question 39

Hydrops hydrallantois how common, presentation, diagnosis, calf and general result

Answer 39

○ Most common, round and tense in abdomen ○ Occurs rapidly ○ Placentomes and calf NOT palpable -> just fill uterus filled with fluid ○ Calf small, often apparently normal ○ Refills quickly if drained - shouldn't try to tap the uterus - Abortion or maternal death

Question 40

Hydrops hydramnios how common, onset, diagnosis, calf and result

Answer 40

``` ○ Uncommon, pear shaped and soft ○ Slow onset ○ Placentomes and calf palpable ○ Calf often malformed ○ Doesn't tend to refill ○ Parturition at full term possible ```

Question 41

Waterbelly calves/foetal dropsy/ascites what is it, presentation, examination and technique

Answer 41

- Accumulation of fluid in perineal space or intestines/rumen - Presentation ○ calf half out but cannot get further but should be able to as small calf - Examination ○ Other pelvic brim has fluid filled belly - Technique ○ Lacerate the calves abdomen to relieve the fluid -> generally the calf is dead by this point

Question 42

Mange mites how host specific, diagnosis, the 3 main types in Australia and what do they lead to

Answer 42

``` ○ 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 ```

Question 43

Boophilus microplus lifecycle, significance and 3 control strategies

Answer 43

§ 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)

Question 44

Photosensitive dermatitis secondary cause pathogenesis

Answer 44

1. Chlorophyll converted to phytoporphyrin ® Phytoporphyrin previously known as phylloerythrin ® Produced by bacteria in the rumen ® Usually conjugated in liver and excreted in the bile 2. Reduced excretion in bile allows build-up 3. Hepatotoxins impair hepatobiliary excretion ® Sporidesmin (pithomyces chartarum), lantana - leads to fascial eczema

Question 45

Facial eczema clinical signs, diagnosis and treatment

Answer 45

○ 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

Question 46

Facial eczema what are the 3 main control methods

Answer 46

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

Question 47

Ocular carcinoma when salvage slaughter is important

Answer 47

§ 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

Question 48

Baldy calf syndrome cause, effect and treatment

Answer 48

○ 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

Question 49

Enzootic bovine leukosis (EBL) cause, significance, presence in australia and risk factors

Answer 49

- 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

Question 50

Enzootic bovine leukosis clinical signs, transmission and diagnosis

Answer 50

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

Question 51

Sporadic enzootic bovine leukosis cause, how common, 3 types and diagnosis

Answer 51

- 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

Question 52

Listeriosis clinical signs and treatment

Answer 52

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

Question 53

What are the 4 main reasons for licking of chewing

Answer 53

1. Foreign body 2. Phosphorus deficiency (pica, lactating beef cattle) 3. Ketosis (chewing) - nervous ketosis as a result of poor nutrition in late pregnancy 4. BSE (bovine spongiform encephalopthy) (nose licking, flehmen, head tossing)

Question 54

Bovine herpes virus what are the 2 forms, predisposed for and clinical signs

Answer 54

- 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)

Question 55

Malignant catarrhal fever main presentation, 3 forms, clinical signs, treatment and what need to differentiate from

Answer 55

- 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

Question 56

Bovine iritis where present, cause, result, clinical signs, diagnosis and treatment

Answer 56

- A disease of the northern hemisphere - recognised in NZ - Silage eye - listeria monocytogenes - Not much conjunctival or corneal ulceration -> beneath the surface of the eye Clinical signs - Iritis, uveitis, keratitis - profuse lacrimation, blepharospasm, vascular engorgement, corneal opacity (temporarily blind) Diagnosis - Condition score and silage feeding +/- bacterial isolation Treatment - Topical Cloxacillin

Question 57

What are some important disease/injuries of the jaw and tongue

Answer 57

1. Actinobacillosis - woody tongue 2. Actinomycosis - lumpy jaw 3. Other trauma, infections, foreign bodies of soft tissue - Salivary gland infections - Blocked salivary ducts - Phlegmonous cellulitis - Propionibacterium infection 4. Fractures of mandible

Question 58

Infectious bovine keratoconjunctivitis in cattle what known as, cause, pathogenesis and clinical signs

Answer 58

PINK EYE - moraxella bovis - Toxins produced by the organism cause inflammation and ulceration of the cornea (and conjunctiva), giving the disease its characteristic appearance Clinical signs - corneal opacity increased, ulcer present - photophobia, blepharospasm - puss and necrotic material within teh centre - if chronic corneal scarring (reduce sight) - if severe eyeball can rupture

Question 59

Hair heelwart/digital dermatitis describe the two main clinical presentations

Answer 59

□ Cleansing exposes reddish granulation tissue (strawberry) with a concave profile □ Lesion is very sensitive and easily bleeds, but the soft tissue is not swollen 2) The proliferative (wart-like) forms □ May give rise to papillomatous type - mass of hard, fine tendrils which can be several centimetres in length and cover a considerable area - chronic □ Can then go back to the erosive phase

Question 60

Hair heelwart/digital dermatitis treatment

Answer 60

○ Treatment § Lesions affecting individuals animals should be treated topically § After cleaning and drying, the lesion should be sprayed with an aerosol containing a solution of oxytetracycline § Herd outbreaks are treated with a footbath containing antibiotic § In general, parenteral antibiotics have not shown any affect on either the erosive or proliferative form of digital dermatitis