Equine Flashcards
1
Q
What are the three clinical signs to look out for with infectious colitis?
A
Acute diarrhoeaFever - temperature over 38.5oCLow white blood cell count - <4x10^9 cells/liter
2
Q
How many of the clinical signs of infectious colitis ar required to assume infection?
A
Two of three
3
Q
Name a gram-ve motile bacillus which causes diarrhoea in horses by adhering to and penetrating the enterocyte membrane and causing hypersecretion of fluid and protein.
A
Salmonella enterica
4
Q
Name a pathogen which is both a facultative anaerobe and facultative intracellular.
A
Salmonella enterica
5
Q
Name the three exotoxin activities of salmonella enterica.
A
cAMPCytotoxinPhospholipase A activity
6
Q
What types of factors can predispose a horse to an infection of salmonella?
A
StressAntibiotic useGeneral anaestheticChange in diet
7
Q
The LPS endotoxin of Salmonella causes what response in the host?
A
Neutrophil dominated inflammatory response by IL1 and TNF release
8
Q
What appearance to cyanotic gingiva have?
A
Purple
9
Q
Flushing of the salmonella bacteria from the body by diarrhoea can lead to what if untreated?
A
Shock, dehydration and cardio-circulatory collapse, tissue necrosis
10
Q
How long can salmonella species survive in damp soil?
A
9 months
11
Q
What is a fomite?
A
A solid object which can spread bacteria
12
Q
How long do horses with an infection of salmonella sp. need to stay in isolation?
A
Until 5 negative faecal samples are collected, each taken 12-24 hrs apart.
13
Q
Which clostridial species are of clinical relevance when discussing GI infection in the horse?
A
PerfringensDifficile
14
Q
Name a pathogen which can cause GI disease in horses but is also regarded as part of the normal gut flora.
A
Clostridium perfringens
15
Q
Which species of clostridium is motile?
A
Difficile
16
Q
Which substances secreted by Clostridium perfringens cause clinical disease in the host?
A
Enterotoxin - cytotoxic
Alpha Toxin - lecithinase
Beta 2 toxin - toxigenic strain
17
Q
Toxin A, released by C.difficile, causes the release of what by the host?
A
Il1 and TNF - causing an inflammatory response
18
Q
Name a type of pathogen which is spore forming and therefore resistant to heat and cold.
A
Clostridium
19
Q
What type of test is used to identify clostridial disease in the horse?
A
ELISA
20
Q
Rotavirus’ are a member of which family of viruses?
A
Reoviridae
21
Q
What is the incubation period for rotavirus infection in the horse?
A
18-24hrs
22
Q
How long to recovering foals shed rota virus after an infection?
A
2 weeks
23
Q
How long do infected foals show signs of rotavirus mediated disease?
A
5-7 days
24
Q
What is the key principle behind biosecurity in veterinary practice?
A
Wash your hands
25
What are the main streptococcal bacteria which cause dermatological disease in horses?
S.equi subspecies equiS.equi subspecies zooepidemicusS.equisimilis
26
Which antibiotic could be used to treat streptococcal dermatitis in the horse?
Penicillin
27
Which type of bacterial dermatitis is characterised by mildly to moderately painful skin infection and abscess?
Streptococcal dermatitis
28
How would pain in a staphylococcal dermatitis differ from that of streptococcal infection?
Staphylococcal infection is much more painful
29
What is the lay term for pastern folliculitis?
Mud fever
30
What clinical condition is also known as rain scald?
Dermatophilosis
31
What bacteria is Dermatophilosis caused by?
Dermatophilus congolensis
32
Which areas of the horse are often affect in rain scald infections?
Persistently soaked areas eg back
33
How is rain scald diagnosed?
Characteristic signs on histology
34
What management protocol should be implemented during rain scald infections?
Put in a dry stableRemove scabs and bathe with antimicrobial
35
What are ringworm infections also known as?
Dermatophytosis
36
What is the incubation period for dermatophytosis infections?
2-3 weeks
37
Name the two main genere of fungi which cause dermatophytosis in the horse.
TrichophytonMicrosporium
38
Why is ringworm infection characterised with bald patches appearing on the horse?
The infection causes weakening of the affected hair causing it to break leading to baldness.
39
What methods can be used to diagnose an infection of ringworm?
Skin scrapHair pluckCulture
40
Name two viral conditions which are characterised by dermatological disease.
Viral papilloma - grass wartsPineal acanthosis - aural plaques
41
What is the most recommended treatment for aural plaques and grass warts?
Leave them alone, the often recover spontaneously
42
What type of fly is responsible for transmitting aural plaques?
Black fly - simulium
43
Which virus causes coital exanthema?
Equine herpes virus - 3
44
Which virus type causes disease characterised by rapidly developing papules on the penis, vulva and perineum?
Ehv3 - coital exanthema
45
How long should breeding be stopped in a horse with coital exanthema?
3 weeks after lesions have healed
46
Sarcoids are tumours of which cell type?
Fibroblast
47
What are the names of the instigating viruses of equine sarcoids?
Bovine papillomavirus 1&2
48
Streptococcus equi var equi is responsible for what infectious disease in the horse?
Strangle
49
Contagious equine rhino pharyngitis is also known by what other name?
Strangles
50
What is meant by the phrase "primary pathogen"?
A primary pathogen is one which is never usually found within the normal horse.
51
A pathogen characterised by its gram positive cocci appearance. It often forms chains of coccus.
Streptococcus equi var equi
52
Which aspect of streptococcus equi var equi structure is important in its protection within the body?
Cell wall m protein
53
What function does the m protein in the cell wall of S.equi var equi serve?
AntiphagocytiticAdhesionProtective
54
Name a type of bacteria which is catalase negative.
Streptococcus
55
What is the mortality rate of respiratory strangles?
2%
56
What is meant by morbidity?
The percentage of exposed animals which become clinically I'll
57
What is the morbidity rate of strangles?
30-100%
58
After how many days will a horse infected with strangles begin showing clinical signs?
3-14 days
59
Which lymphnodes of the horse are most commonly affected by strangles?
Retropharyngeal and submandibular
60
Where is the most common site for carrying S.equi var equi? How many horses infected with the bacteria will become shedders?
Guttural pouch10%
61
What would be feeding instructions for horses with strangles?
Soft, palatable feeds
62
Small stones of inspissated pus found within the guttural pouch which lead to shedding of the strangles bacteria are also known as what?
Chondroids
63
Purpura haemorrhagica is caused by what type of sensitivity?
Type 3
64
What drug types do we use to treat purpura haemorrhagica?
Immunosuppressants
65
Name three types of test used to diagnose strangles
PCRELISACulture
66
How many guttural pouch washes are needed with negative results until you can assume the horse is negative for strangles? How many nasal swabs are needed?
1 3
67
How long can S.equi var equi survive on pasture?
Around two months
68
How long can the carrier status of a horse with strangles persist?
7-39 months
69
How long should horses affected with strangles be isolated for?
3-6 weeks
70
How long should a horse new to a yard be isolated for?
2 weeks
71
What are the characteristics of the strangles vaccine of horses?
Modified live strain
72
How is the strangles vaccine administered and why?
Submucosa line the gum/lipIt is at its site of action immediately
73
Which bacteria can cause suppurative bronchopneumonia in foals aged 1-4 months?
Rhodococcus equi
74
How does the rhodococcus bacteria appear histologically?
Gram positive pleiomorphic rod - coccus becomes bacillus
75
Name three virulence factors of rhodococcus equi.
LPS - prevents phagocytosis
Inhibitory surface antigens - intracellular
VAPs only expressed at 34-41oC
76
At what age are foals first infected with rhodococcus?
\<2-4 weeks
77
What is the incubation period of rhodococcus bacteria?
10 days to 3 weeks
78
How does rhodococcus bacteria evade the immune system?
Poor chemotactic effects
Intracellular
Poor immunogenicity
Lipid capsule
79
Which resident macrophages does R.equi replicate within?
Alveolar macrophages
80
What types of lesions are characteristic rhodococcus infections?
Granulomatous lesions of the lungs
81
What preventative measures can be taken to reduce R.equi infection in foals?
Plasma infusion at birth
Hygiene
Early recognition and isolation
Irrigation of pastures
82
What is the protocol for giving hyperimmune plasma to foals to prevent rhodococcus equi?
Give aged 24-72 hours Repeat at 21 days
83
What is shipping fever? Why does it happen?
Pleuropneumonia infection of mixed bacteriaTraveling causes stress, also since heads are tied up drainage of the sinuses
84
Which strains of equine influenza are currently of interest for vets?
H3N8 - particularly the Florida clade 2 strainH7N7 - rarer and older strain
85
What is the function of haemagglutinin surface molecules of influenza virus?
Adhesion to the respiratory mucosa
86
What is the function of neuraminidase surface molecules of influenza virus?
Entrance into the respiratory mucosa
87
How long do the symptoms of influenza last?
1-2 weeks
88
How long is the incubation period of influenza viruses within the horse?
24-48 hrs
89
Name some techniques which can be used for the diagnosis of viral respiratory disease.
PCR
Ab titres
ELISA
Haematology
90
Outline the influenza vaccination protocol given by the jockey club.
D0 = 1st vaccine21-92 days after the first = 2nd vaccine 150-215 = 3rd vaccine Then boosters every year after that
91
What concept causes influenza virus strains to rapidly alter, therefore producing lots of different strains?
Antigenic drift
92
West Nile virus is an example of which type of virus?
Arbovirus \> flaviviridae
93
Outline the pathogenesis of west Nile virus.
1 - virus replicates at the site of inoculation
2 - viraemia - fever depression and anorexia
3 - CNS (muscle tremors, weakness, ataxia, mentation deficits)
94
Outline the treatment and diagnosis of WNV. How can the spread of disease be prevented?
T - hyperimmune plasma (USA only) alongside supportive care.D - ELISA, PM P - vaccination and reducing contact with vectors (flies)
95
What species of animal is the main reservoir of WNV?
Bird (transmitted to biting flies then to horses)
96
Which herpes virus is specific to the horse?
EHV1 an alpha herpes virus
97
How can an infection of EHV1 be treated?
Anti inflammatories and supportive care, beware of long periods of recumbency, horses lying down should be turned every 4-6 hours, slings may also be used (stress)
98
What clinical signs are seen with an infection of EHV1? Which initial pathogenesis causes these signs?
CS - ataxia of HIND or all limbs, atony of the bladder, flaccid tail and anus, perineal hypoplasia, may see cranial nerve involvement.Factor - vasculitis and thrombosis of the arterioles of the brain and spinal cord
99
Which clinical signs of EHV1 are caused by damage to the cauda equina?
Atony of the bladder, perineal hypoplasia, flaccid tail and anus
100
Name a lyssavirus which can affect the horse.
Rabies
101
Outline the transmission of rabies. How long can the virus be incubated in the body?
Transmitted by contaminated saliva on bite wounds. Incubation of the virus can be from weeks to years depending on the strain.
102
How do the clinical signs of paralytic, dumb and furious rabies differ? Which areas of the CNS do they affect?
P - hyperaesthesia, progressive ataxia and lameness, can be recumbent for 3 - 5 days. SPINAL FORM
D - depressed, anorexia, excessive salvation. BRAIN STEM
F - aggression, muscle tremors, seizures. CEREBELLUM
103
What percentage of human cases of rabies are fatal?
100%
104
Briefly outline the clinical signs of equine herpes virus 1 - 8.
1 - myeloencephalitis, respiratory, abortions. 2 - keratitis. 3 - coital exanthema. 4 - respiratory. 5 - multinodular pulmonary fibrosis. 6 to 8 - donkeys.
105
Describe equine rhino virus.
No vaccine. Last 3 - 5 days. Severe nasal discharge and pyrexia and respiratory disease
106
What virus is most commonly associated with abortions in late pregnancy?
EHV1
107
Which notifiable virus can be shed for an extended period via the accessory sex glands of stallions, after clinical infection has subsided?
Equine Arteritis Virus
108
Name an equine Picornaviridae.
Equine Rhinovirus (also FMD)
109
How is equine arteritis virus dealt with?
Name and shame stallions
Castrate effected - virus can't be maintained (lack of testosterone)
110
Clinical signs of Equine arteritis.
* Mild URT infection
* General depression, anorexia, (cough)
* Peripheral oedema
* Skin oral papules
* Abortion
* Vulval discomfort
* Stallions ~ urethral and penile swelling
111
How is EVA transmitted?
Venereal and inhalation.
