ID Flashcards
(122 cards)
1
Q
How long does it take the teat sphincter muscle to close? (cows)
A
20-30 mins
2
Q
What part of a cow’s teat traps bacteria?
A
Keratin lining
3
Q
What type of antibiotics are used to treat streptococcus agalactiae?
A
Beta-lactam eg penicillin
4
Q
What is summer mastitis spread by?
A
Hydrotea irritans (sheep head fly)
5
Q
What are the classic clinical signs of summer mastitis?
A
Hot, hard, swollen, very painful udder with a thick purulent secretion.
The cow may also be lame and systemically ill
6
Q
Name some congenital abnormalities seen in sheep affected by Schmallenberg
A
Bent limbs and fixed joints Twisted neck or spine Domed head Short lower jaw Live “dummy” Blindness Wobbly Inability to suck Fitting
7
Q
Fusion proteins induce fusion between what?
A
Between the viral envelope and the target cell membrane
8
Q
Strangles is caused by which bacteria?
A
Streptococcus equi
9
Q
What is mastitis and what are the 2 types?
A
Inflammation of the mammary gland
Clinical and sub-clinical
10
Q
How are Marek’s disease vaccinations administered in broilers?
A
Done at day 1 in hatchery
0.2ml of live vaccine SC in back of neck
Only live vaccine given this way (all others are in between superficial and deep pectorals)
11
Q
When are in ovo vaccines carried out in poultry?
A
18 days of incubation
12
Q
Greasy pig disease is caused by which bacteria?
A
Staphylococcus hyicus
13
Q
Porcine skin lesions are commonly seen where?
A
Legs, tail and flanks
14
Q
What kind of skin lesions are seen in pigs?
A
SHOULDER SORES: associated with weight loss during lactation and rough surfaces
LOWER LIMB ABRASIONS
STIFLE SORES: mainly in fast growing finishers, kept at high density, no bedding
TEAT NECROSIS in piglets: can affect future breeding potential. Can stick tissue paper over front 6 teats at birth
Treatment: removal from offending area, and soft, comfortable bedding and surroundings
15
Q
Give some non-infectious causes of skin lesions in pigs
A
Sunburn- blistering and ulceration
Transit erythema- scalding by urine or chemicals
Hyperkeratosis- water trough overhead leads to stagnant humid atmosphere -> flaking of dorsal skin. No clinical importance.
16
Q
Give the 5 ways of preventing mastitis
A
Genetics: breed for udder health
Nutrition: minimise acidosis/ loose faeces
Stage of lactation: 10-12 months milking, 2 months dry period
Vaccination: E.coli and Staph aureus
Stress: minimise!
17
Q
Give the virulence factors of Staph. aureus (causes mastitis)
A
Pseudocapsule prevents phagocytosis
Alpha toxin produced in large amounts
Haemolysins damage tissue and cells -> aids intracellular colonisation
Protein A in cell wall binds antibody -> prevents recognition by neutrophils
Clumping factor A allows adherence of pathogens to gland tissue
Can survive intracellular killing and multiply within phagocytes
Survive in keratin of teat canal
B lactamase makes them resistant to penicillin
Exotoxins damage udder tissue -> fibrosis, abscessation
18
Q
Give the 4 grades of staph aureus mastitis
A
Sub clinical: persistent high SCC
Clinical grade 2A: acute mastitis, udder hot, swollen, painful
Clinical grade 2C: blockage of secretory ducts, fibrosis, abscessation within udder, bacteria persists in abscesses tissues
Clinical grade 3, gangrenous mastitis: newly-calved cows, toxaemic (α toxins), gangrene of udder tissue, necrosis, sloughing, milk often dark red and bloody
19
Q
Which drugs are used to treat staph aureus mastitis?
A
Penicillin (if not resistant)
Cloxacillin tubes +/- tylosin systemically
20
Q
What can you use to treat streptococcus agalactiae or dysgalactiae mastitis?
A
Beta lactams eg penicillin
21
Q
Which 2 species of Mycoplasma cause mastitis?
A
M. bovis and M. californicum
Both contagious
22
Q
How does mycoplasma cause mastitis?
A
Lipoprotein on outer surface -> stimulates host immunity -> alveolar epithelium degenerates -> outpouring of leukocytes -> abscesses, alveolar hypertrophy, fibroplasia around ducts -> destroyed quarter
23
Q
When would you give the vaccine ‘Startvac’ for mastitis?
A
3 doses:
45 days pre-calving
10 days pre-calving
7-8 weeks post-calving
24
Q
Summer mastitis typically affects which cows?
A
Dry cows and heifers outdoors in summer
25
Summer mastitis is caused by which agents?
Mixed infections with T.pyogenes, Strep dysgalactiae, Fusiformus necrophorum, Peptococcus indolicus, Bacteriodes melaninogenicus, Arcanobacterium pyogenes
26
How would you treat Summer mastitis?
Systemic antibiotics plus manually stripping 3x daily for drainage
Affected quarter is irreparably damaged
27
The vaccine 'Startvac' protects against which types of mastitis?
Coliforms (eg e.coli), staph aureus, coagulase-negative staphylococci
28
What are the 2 types of ETEC enterotoxins that cause calf diarrhoea and how do they work?
Heat-stable enterotoxin (ST):
-Produces a rise in c-GMP -> inhibits absorption of Na+ Cl- and H2O
Heat-labile enterotoxin (LT):
-Produces a rise in c-AMP -> inhibits absorption of Na+ Cl- and H2O in villus cells; stimulates secretion of Na+ Cl- and H2O in crypt cells
29
What is the definition of diarrhoea?
Failure of net intestinal uptake of water and sodium such that the colon is overwhelmed
30
What are adjuvants and which is the most common one in use?
Compounds delivered with the antigen in a vaccine that help develop the immune response
Most common = aluminium salts (long safety record)
31
What is meant by herd immunity?
Vaccination of a proportion of the population gives protection to the entire population
Levels of the population to be vaccinated to give herd immunity is high
32
An abortion percentage of what value would indicate a problem in a flock?
>2%
33
What is the gestation of a sheep?
147 days (140-150)
34
What is the most common cause of abortion in sheep?
Chlamydia abortus
35
Describe the pathogenesis of Chlamydia abortus in sheep
Main source of infection=aborting ewes; discharges and products of abortion are heavily contaminated and viable for several days
Carrier ewes may or may not abort, but shed at lambing and oestrus
Oral route
Indoor lambing
36
What are the possible outcomes of exposure of Chlamydia abortus in sheep?
Pregnant: abortion after 90 days, often in last month
Not pregnant: will harbour infection in repro tract, will abort next lambing
Ewe lambs born to infected ewes can become infected and abort in their first lambing
Once aborted, most ewes become immune and will not abort again, but some will become carriers and shed at oestrus and lambing
37
Give the pathology of abortion caused by Chlamydia abortus
Bacteria replicates in the trophoblastic epithelial cells -> severe placentitis with thickening and necrosis -> affects transport of nutrients and hormone production -> death or damage to lamb (inflammation of internal organs)
38
Give the clinical signs of Chlamydia abortus in sheep
Abortion after 90 days of pregnancy, often in last month
Death of both lambs/ birth of weak lambs/ birth of one live and one dead
Ewes: vaginal discharge for a couple of days
Sheep are rarely ill, occasionally metritis (can be fatal)
39
How would the placenta look if a sheep was infected with Chlamydia abortus?
Necrotic placentitis
| Intracotyledonary thickening
40
How can you reduce abortions in sheep from Chlamydia abortus?
Give all ewes yet to lamb (>90 days) 20mg/kg oxytetracycline long-acting
Repeat in 2 weeks
Vaccinate next year with Enzovax (live attenuated, strong immunity, reduces spread, give up to 4 weeks before tupping)
41
What are the infection outcomes of a sheep infected with Toxoplasma gondii?
Non-pregnant: develop immunity
Early pregnancy: foetal resorption, appears barren
Mid pregnancy: foetal death/ deformity/ mummification
Late pregnancy: abortion/ weak lambs/ immune lambs
42
'Strawberry cotyledons' are seen with which condition?
Toxoplasmosis in sheep
43
When would you vaccinate sheep against Toxoplasmosis?
At least 3 weeks prior to tupping
| 'Toxovax'; live attenuated
44
In sheep, when does abortion from Salmonella abortus ovis occur?
Last 1/3 pregnancy
45
'Hairy shaker' lambs are associated with what?
Border disease (pestivirus)
46
What are the clinical signs of Schmallenberg in adult animals?
Cattle: diarrhoea, fever, milk drop (50%), recover quickly in 2-5 days
Sheep: no apparent clinical signs. Increased rate of barren ewes. Dairy sheep- diarrhoea, milk drop
47
How is Schmallenberg spread?
Midges
48
Which birth defects are seen with Schmallenberg?
```
Bent limbs, fixed joints
Twisted neck or spine
Domed head
Blindness
Short lower jaw
Wobbly
Inability to suck
Fitting
```
49
Vaccines are available for which causes of abortion in sheep?
Chlamydyophila ('Enzovax')
Toxoplasma ('Toxovax')
Schmallenberg ('Bovilis SBV')
50
In which ways can pigs get infectious diseases?
Direct pig-to-pig contact
Fomites
Infected semen
Humans (can carry viruses on their nasal mucosa)
Carrier pigs
Movement of animals over large distances increases possibility of geographical spread of disease
51
Porcine reproductive and respiratory syndrome virus targets which cells?
Where do they replicate?
Alveolar macrophages
| Replicate in the perinuclear cytoplasm of host cells
52
What clinical disease is seen in pigs with porcine reproductive and respiratory syndrome virus?
Give the clinical signs associated with pigs of different ages
Sow: abortion or premature farrowing, still born piglets, weak live piglets, anorexia, fever, pneumonia, delayed return to service
Neonatal pig: dyspnoea, CNS signs, high mortality
Grower pig: increased mortality, secondary infections, failure to thrive, fever, pneumonia
Finishing pig: fever, decreased feed consumption, pneumonia
Boar: fever, semen changes
53
Give some causes of swine influenza virus
```
Stress
Carrier pigs
Infected animals eg people, pigs, birds
Birds are reservoirs of infection esp waterfowl
Secondary bacterial infections
Fluctuating temperatures
Poor nutrition
Wet bedding and floor surfaces
```
54
Give some clinical signs of swine influenza virus
Fever -> abortion
Widespread coughing
Pneumonia
Inappetence
55
When are piglets weaned?
3-4 weeks old
56
When do sows return to heat after weaning?
6 months
57
How old are pigs when slaughtered?
20-24 weeks (4-6 months)
58
How can you prevent tail biting in pigs?
Tail docking
Straw bedding
Toys eg balls, CDs hung on string
Farm assurance legislation now ensures that all pigs must have playthings in a pen which they can chew and destroy = ‘manipulative material’
59
Which vector-borne diseases are transmitted by ticks?
Lyme disease
Tick-borne rickettsias
African swine fever
60
Which vector-borne diseases are transmitted by mosquitoes?
Heartworm
| West Nile fever
61
Which vector-borne diseases are transmitted by midges?
Schmallenberg
African horse sickness
Bluetongue
62
Which vector-borne disease is transmitted by sandflies?
Canine leishmaniasis
63
What is meant by an emerging disease?
A disease that has newly appeared in a population, or that existed previously but is rapidly increasing in incidence or geographic range
64
What is meant by a vector-borne disease?
A disease caused by a pathogen spread by an arthropod host (insect, tick, crustacean)
65
Give the clinical signs of Lyme disease in dogs
Not of major clinical importance
| Fever, inappetence, lameness, joint swelling (polyarthritis, Lyme arthropathy), swollen lymph nodes, lethargy
66
How is Lyme disease spread?
Ixodes ricinus (sheep/deer tick)
67
Borrelia burgdorferi is also known as what?
Lyme disease
68
Which tick is also a vector of Rickettsia rickettsii?
```
Rhipicephalus sanguineus (brown dog tick)
Can be fatal
```
69
Give 3 factors which influence the emergence of hard tick-borne diseases
Spread of ticks (probably related to climate)
Increased movement of animals (dogs)
Changes in international regulations (stopping of tick treatments for imported dogs)
70
Describe African Swine Fever
Spread by Ornithodorus (soft tick), aerosols or in feeds
Causes fatal haemorrhagic disease of pigs
Highly stable virus, eg can survive 15 years in frozen meats
No vaccine
Outbreaks dealt with by culling
71
What are the 2 main divisions of mosquitoes?
Invasive
| Indigenous
72
Which filarial nematodes do mosquitoes transmit?
Dirofilaria immitis (heartworm) and Dirofilaria repens (skin)
73
What are the vectors of West Nile Virus?
Which species does it affect?
Describe it
Transmitted by Culex mosquitoes
Birds are natural hosts
Humans and horses are dead end hosts
Causes severe disease and death in horses
Causes fatal neurological disease in humans
Culex modestus = vector in UK (Brits are modest)
74
What is canine leishmania transmitted by?
What is the most common species of Leishmania in Europe?
What are the clinical signs?
Phlebotomus sandflies
Leishmania infantum
Variable: anorexia, weakness, weight loss, enlarged lymph nodes, local cutaneous lesions, can be fatal
75
Give the characteristics of transmissible spongiform encephalopathy diseases (TSE)
```
Long incubation period
Progressive and fatal
Holes in brain give spongiform texture
No signs of fever, inflammation, infection
No antibody response
No signs of a pathogen with a genome
```
76
With regards to prions, what causes TSE diseases? (transmissible spongiform encephalopathies)
Caused by a prion encoded by the PrP gene (protease-resistant protein)
PrPc is normal
PrPSc is infectious
PrPSc converts PrPc to PrPSc
PrPSc is partially resistant to digestion -> accumulates -> disease
77
Give the clinical signs of Scrapie
Sheep and goats
| Ataxia, tremors, rubbing/scratching, loss of condition, death in 1-3 months
78
What is the incubation period of scrapie?
2-5 years
79
In which ways can sheep catch scrapie?
```
Vertical transmission (in utero)
Pseudo-vertical transmission (lambs infected at birth from infected birth tissues)
Horizontal transmission (adult to adult/lamb)
Contaminated land (adult to adult/lamb; sheep catch Scrapie on land where infected sheep used to live)
Iatrogenic (adult to adult/lamb; needle contamination, blood transfusions)
```
80
Give the clinical signs of BSE
What is the incubation period?
How is it transmitted?
How many strains are there?
Ataxia, nervousness, sensitivity to touch
5 years
Oral route
2 strains
81
Which species does Chronic Wasting Disease affect?
| What are the clinical signs?
Deer and elk
Loss of condition, standing apart from herd, listlessness, ataxia, nervousness, PUPD
Aspiration pneumonia=cause of death
82
What are the 2 main food-borne serotypes of Salmonella in poultry?
Salmonella typhimurium
Salmonella enteritidis
(Salmonella enterica subs. enterica serotype Typh/Enter...)
83
What are the clinical signs of Salmonellosis in poultry?
Anorexia, stunted growth, dullness, dehydration, septicaemia, enteritis, focal necrotic lesions in mucosa of SI, inflammation of liver, spleen, kidney
84
What are the clinical signs of salmonellosis in humans?
Gastroenteritis, vomiting, diarrhoea, fever
85
What is the best treatment for coccidiosis in poultry?
Toltrazuril (Baycox) in drinking water
86
Which is the only poultry worm to not colonise the intestinal tract?
Gapeworm -> infectious laryngeal tracheitis, coughing with blood
87
Which drug is a licensed wormer for internal worm parasites of poultry?
Flubendazole (in food for 7 days)
88
What clinical sign would be seen with Histomonosis (Blackhead) in poultry?
Yellow diarrhoea
| Fatal if not caught early
89
How do coarse spray vaccinations work in poultry?
| Which type of diseases do they protect against?
Droplets cover the birds
Vaccine is inhaled or pecked off feathers
For respiratory diseases
90
How do in ovo vaccinations work?
| What are the advantages?
Vaccines are injected through shell into fertile egg at 18 days of incubation
The embryo is 'bathed' in vaccine, immune response begins early
Avoids handling hatched chicks, can be done mechanically, many eggs can be vaccinated at once by a machine
Appears superior to spray/drinking water application
91
Why might a vaccine fail in poultry?
Host factors: inappropriate age of vaccination, immunosuppression, birds already infected with field virus prior to vaccination, stress
Environment: too hot/cold (stress), inappropriate ventilation, high dust/ammonia, water contaminated with chlorine/anti-microbial agents
Agent/vaccine: wrong strain, inaccurate dilution/administration
92
When administering spray vaccines to chicks, what is the volume of water administered per chick box?
20-35ml per 100 chicks
| Appropriate coverage of the chicks is more important than droplet size
93
How must live vaccines for Mareks and Gumboro be stored and handled?
Stored frozen in liquid nitrogen (-196oC)
Thawed out in water bath (27oC) within 90 seconds
Must be used within 1 hour of preparation
Once in bag, agitate regularly to ensure vaccine is well mixed
94
Mannheimia haemolytica classically follows which disease in ruminants?
IBR (Bovine herpes virus)
95
"Cuffing pneumonia" is associated with which disease of ruminants?
Mycoplasma bovis
96
With which virus of sheep can a ewe be held by its back legs, only for a white pulmonary surfactant to flow out of the nose?
OPA
97
Which bacteria of sheep is commensal in the genital tract but pathogenic in the respiratory tract?
Histophilus somni
98
What kind of virus is foot and mouth disease?
An Aphthovirus
99
What are the clinical signs of foot and mouth disease?
Fever, lameness, lesions on tongue, feet, snout, teats
100
Which organism is the most frequently reported organism found in digital dermatitis lesions?
How can it be identified?
Spirochaetes
| Spiral organism identified through staining with silver nitrate
101
Give some common treatments for bovine digital dermatitis
No single effective treatment
Footbaths: chemical (copper sulphate) or antibiotic (eg lincospectin)
Topical treatments: tetracycline (blue) spray
Penicillin (systemic) or macrolides (systemic/oral) although milk withhold and antibiotic stewardship issues so not used
102
What are the suspected aetiological agents of bovine digital dermatitis and contagious ovine digital dermatitis?
Treponemes eg T. medium-like
103
When are you most likely to see outbreaks of bovine digital dermatitis?
Winter ie housing months
104
How does transmission of bovine digital dermatitis and contagious ovine digital dermatitis occur?
Direct contact, spread from foot trimming equipment, slurry, GI tract is a reservoir
105
What % of UK sheep flocks are considered to have contagious ovine digital dermatitis (CODD)?
35-53%
106
What is the primary cause of ovine footrot?
Dichelobacter nodosus (rod, gram -ve anaerobe)
107
Give the pathogenesis of Dichelobacter nodosus (ovine footrot)
Produces extracellular proteases
Has fimbriae -> motility and adherence
Fimbrial proteins = highly immunogenic
108
What is the most common cause of lameness in sheep?
When does it occur?
What causes it?
Ovine interdigital dermatitis (scald)
Occurs when wet underfoot
Dichelobacter nodosus
109
What are the causative agents of bovine footrot (foul in the foot/interdigital necrobacillosis)?
Fusobacterium necrophorum and Bacteriodes melaninogenicus
110
What is the treatment for bovine footrot (foul in the foot/ inerdigital necrobacillosis)?
3 days of systemic penicillin/oxytet/macrolide
111
Briefly describe the Dutch Formulary for Cattle Treatment of antibiotics
Give an example of a first, second and third choice drug and say when they would be used
First Choice: (bacteria does not induce ESBLs or AmpC beta-lactamases-resistance) eg Penicillins, tetracyclines, macrolides
Second Choice: (bacteria is resistant) eg amino-penicillins, 1st and 2nd gen cephalosporins, aminoglycosides
Third Choice: (only after individual bacteriology has been performed, and no alternatives are available) eg fluoroquinolones, 3rd and 4th gen cephalosporins
112
What is the aim of dry cow therapy?
To reduce mastitis and SCC
113
What does MIC stand for?
Minimum Inhibitory Concentration
114
What is the drug of choice for coughing/pneumonia in calves?
Oxytetracycline
115
What is the drug of choice for endometritis 10 days post-calving?
1st gen cephalosporin (2nd line treatment)
116
What should you include in an audit of antimicrobial use in cattle?
Which conditions are being treated?
What evidence of efficacy is available?
Are products prescribed/dispensed and used consistently with farm policy?
List of common conditions requiring treatment (that covers 80% of AB use)
Develop a plan with first and second line treatment for each of the conditions based on current data
117
Which drug is used to treat fungal skin infections?
Itraconazole
118
Which drugs are used to treat hypersensitivity skin reactions?
Corticosteroids, ciclosporin
119
Which drugs are used to treat immune-mediated skin conditions?
Corticosteroids
120
Describe cowpox
```
Cats
Virus
Carried by rodents
Viraemia -> lymphoid tissues
Pox like lesions usually on face
Recover without treatment in 6-8 weeks, can give antibiotics for secondary bacterial infections. Don't give steroids -> immunosuppression -> severe generalised systemic infection -> fatal pneumonia
```
121
What are the 4 primary feline cutaneous reaction patterns?
Symmetrical alopecia
Head and neck pruritus
Miliary dermatitis
Eosinophilic granuloma complex
122
Compare ringworm to false ringworm in pigs
Ringworm: caused by Trichophyton nentatigrophytes, involves contact with rodents (or cats-Microsporum canis). Groups of animals, dirty marks on skin
False ringworm: caused by Pityriasis rosea. Inherited: develops at 6-8 weeks old, disappears without treatment at 20 weeks. Paler lesions. Individual animals
