State Vet Med Flashcards Preview

FINALS > State Vet Med > Flashcards

Flashcards in State Vet Med Deck (53)
Loading flashcards...

List the notifiable diseases present in cattle?

Anthrax, BSE, Brucelosis, Contagious bovine pleuropneumonia, Enzootic bovine leukosis, Foot and mouth disease, rinderpest, Tuberculosis, Warble fly, blue tongue


List the notifiable diseases in pigs?

Aujeszkys disease, classical swine fever, swine vesicular disease.


List the notifiable diseases present in poultry?

avian influenza, newcastle disease, paramyxovirus of pigeons.


List the notifiable diseases in sheep?

brucellosis melitensis, bluetongue, scrapie, sheep pox, sheep scab


List the notifiable diseases in deer?

chronic wasting disease, warble fly


List the notifiable diseases in horses?

contagious equine metritis, epizootic lymphangitis, equine infectious anaemia, equine viral arteritis, glanders and farcy, west nile virus, warble fly.


What distance are the protection and surveillance zones when a notifiable disease is confirmed?

3km protection zone on neighbouring farms
10km surveillance zone


What are the clinical signs of foot and mouth disease?

Incubation Period is usually between 2- 10 days. Initially there is pyrexia, anorexia, salivation, severe lameness and reduced milk yield are seen, accompanied by a serous occulo nasal discharge which often becomes muco purulent. Early lesions in the mouth are seen on the tongue and dental pad appearing as blanched, circular areas which swell with fluid and become vesicles. Those on the dorsum of the tongue often coalesce until the whole surface of the tongue appears corrugated. Vesicles usually rupture within one or two days of their formation leaving shallow deep red sharp edged ulcers. Ulcers on skin of coronary band and interdigital cleft. May extend to bulbs of heels. Cattle move their tongue and jaw producing a characteristic champing which churns the saliva into a froth which hangs in strings from the mouth. Affected animals paddle form one foo to the other and lie down frequently. Sheep may show little more than a day or twos lameness.


How is a diagnosis of foot and mouth disease made?

Clinical signs, history of contact with imported animals, recent reports in th area. laboratory confirmation using ELISA and PCR tests and virus isolation. Vesicular epithelium is a particularly good source of virus.


You are presented with a lesion on the muzzle/mouth of a cow. what are your differentials?

Mucosal disease
Vesicular stomatitis
Bovine papular stomatitis
Necrotic stomatitis
Blue tongue


What is rinderpest? what animals does it affect?

A morbilli virus related to peste des petits ruminants, possibly now eradicated. many wild animals (any even toed ungulates) are susceptible. Transmitted by direct contact with a sick animal e.g aerosol or indirect transmission e.g via meat possible but not common.


What are the clinical signs of rinderpest

Fever, anorexia, serous secretions then at 2-5 days small raised areas of necrosis on the mucosa of the mouth and nose which develop into ulcers. Excess salivation. After that > mucopurulent discharges and a profuse diarrhoea, followed by dehydration and death after 6-12 days.


How is rinderpest maintained?

In naive populations, morbidity and mortality are high and the disease reaches plague proportions. in endemic areas RP may be mild and spreads slowly. It may only become apparent when it affects in contact wildlife. RP is maintained because of innate resistance of indigenous cattle, mild strains of the virus, continuous presence of susceptible animals in large herds. Recovered animals are solidly immune. there are no carriers.


What is peste des petits ruminants?

A disease similar to RP caused by a closely related virus, affecting goats and sheep. It is common in west africa, also present in africa and parts of Asia. There is no global eradication programme for PPR at present.


What is the causative agent of Contagious bovine pleuropneumonia?

Mycoplasma mycoides subspecies mycoides. The natural host are cattle and water buffalo possibly susceptible. It is introduced to a herd by a carrier or by contact with an affected herd at grazing or watering.


What are the clinical signs of contagious bovine pleuropneumonia?

Fever, coughing, rapid painful breathing, moist cough, rales, interstitial pneumonia with pleurisy. About half of the clinically sick animals die. Survivors may have residual lesions in lungs and are potentially infectious for the rest of their lives.


What is lumpy skin disease?

A capripox virus, family poxviridiae related to sheep and goat pox. transmitted by biting insects,


What are the clinical signs of lumpy skin disease?

Fever, depression, firm swellings through full depth of skin, skin over swelling separates from surrounding tissue but remains attached by a core (sitfast), oedema around lumps, oedema of limbs, swollen glands.


What is rift valley fever? what are the clinical signs?

Phlebovirus spread by aedes macintoshii. The reservoir host is forest mammals. Affects cattle, sheep, goats. Accidental infeciton in man. Inapparent infections in indigenous livestock but causes sporadic outbreaks in improved breeds. outbreaks occur in rainy season, especially in high rainfall years. Serious epidemics when vector extends its normal range. The clinical signs are fever, drop in milk yield, abortion in endemic areas. Severe disease in exotics and in epidemics with jaundice, dysentery, deaths especially in young stock.


What is the vector of bluetongue?

Blue tongue is an orbivirus, transmitted by culicoides species. (c imicola in africa & europe). Affects sheep but also affects cattle, goats and other ruminants. Cattle are the natural resevoir. Incubation 7-14 days. Clinical signs = Fever, anorexia, respiratory distress, encrusted or bleeding lips, swelling and cyanosis of the tongue, ulcers in the mouth.


What are the vectors of african horse sickness?

Culicoides imicola


What are the clinical signs of african horse sickness?

Incubation is 2-21 days. High fever, severe respiratory distress, subcutaneous oedema of the head especially supra orbital fossa, also neck, abdomen, death within 7 days.


What would make you suspiscious of african horse sickness? what other diseases do you need to rule out?

A peracute or acute febrile disease, with subcutaneous swellings on the head, differentiate from anthrax, equine viral arteritis, purpura haemorrhagica, babesiosis, trypanosomiasis.


How did bluetongue virus get to britain?

The vector in africa moved up to the mediterranean basin was culicoides imicola. This species is shown to have spread by wind into countries in north mediterranean basin such as cyprus, turkey and spain. Culicoides imicola seems capable of natural spread into hot, dry southern european countries. Northern european species such as C obsoletus and C pullicaris are shown in laboratory to be capable of transmitting the virus, especially in warm conditions when the virus can get through the barrier of the insect gut and haemolymph more easily. Virus in transported cattle or sheep can be picked up by local C obsoletus and transmitted to local non immune livestock. Establishment of transient local endemic foci by these species is likely.


Describe the pathogenesis of bluetongue?

BTV replicates in haemopoeitic and lymphoid tissues including tonsils, spleen, bone marrow, monocytes, macrophages. Lesions can occur in many organs and are related primarily to a breakdown int he microvasculature resulting in thrombosis, haemorrhage, oedema, ischaemia and necrosis of surrounding tissues. Affected organs include tonsils, heart, lungs, spleen, thymus, kidneys, skeletal muscles and a range of other tissues. Skeletal muscle degeneration is frequently seen as focal areas within the muscle mass associated with haemorrhages and oedema. In the squamous layers of the skin and mucosa, vacuolation and necrosis of the epithelial cells can occur, developing into erosions and ulcerated areas in more chronic cases. Foetal infection at the 5 and 6 week stage, particularly with attenuated vaccine strains can cause encephalopathies and malformation.


What are the clinical signs of bluetongue in sheep?

Fever, oedema particularly of the head and neck, hyperaemia of the lining of the mouth, nose and eyelids, haemorrhages under skin, coronitis, lameness, respiratory distress, ocuo nasal discharges, loss of appetite, wasting, discolouration of tongue is rare,


What are the clinical signs of bluetongue in cattle ?

Lethargy and fever, conjunctivitis, lacrimation, inflammation of the pericoular skin, necrotic lesions on muzzle, muco haemorrhagic nasal discharge, drooling of saliva, swelling inside mouth and ulceration of the oral mucosa, swelling of the head and neck, oedema of legs, oedema and swelling of teats, ulcers on the udder, drop in milk production, loss of body condition.


What is anthrax?

Anthrax is an acute and generally fatal disease caused by bacterium bacillus anthracis. All species of animal are susceptible. Generally cattle and pigs are the farm animals most frequently affected in GB. Disease usually presents as sudden death.


If an affected animal does not die straight away with anthrax, what clinical signs may be observed?

High temperature, shivering, twitching, harsh dry coats, fits, bright staring eyes, colicking pains, dejection, refusal of food, and marked decrease or complete loss of milk. In pigs and horses, a hot painful swelling in the regions of the throat may be present, pigs may just go off their food for a day or so.


What should be done with an animal that is suspected to have died from anthrax?

It should be isolated and police informed if still alive. When found dead, it should not be moved, skinned or cut open. Vermin must be kept away and police informed. any blood should be mixed with defra approved disinfectant. This will destroy the anthrax organisms before they have time to form spores. Animals that have been in contact with a suspected animal should be watched carefully and isolated at once if they show similar symptoms. Especially if cows in milk are affected. Milk may contain anthrax bacilli.


What is the treatment of anthrax? how can it be controlled on a farm if one animal has died?

Treatment is seldom possible due to rapid and fatal course, but if time permits antibiotic drus may be used with good effect (penicillin). If animals are likely to be continually exposed, then vaccination with antrhax spore vaccine is recommended. The vaccine is safe to use and protects animals for six months or more.


What is Enzootic bovine leukosis? what are the clinical signs?

EBL is caused by a retrovirus. It can be transmitted both vertically, mother to calf and horizontally cow to cow causing leukaemia and multiple tumours. Usually apparent in cattle between 4 and 8 years of age, rarely seen in animals under 2yo. In the live animal, the disease is characterised by chronic ill health, progressive loss of condition, weakness, anaemia and anorexia, attributable to tumorous infiltration of various organs throughout the body.


What is warble fly and why is warble fly a problem in cattle?

Warble fly is an insect which parasitically infects cattle. Horses and deer can also be infected. It was ruining hides that otherwise would be used to make items such as coats bags and shoes.


What is the life cycle of the warble fly?

Adult warble flies are hairy and about the size of small bees with yellow orange abdomens. the fly lays eggs on the hair of cattle during summer. after about 4 days larvae hatch and migrate into the skin. The larvae move between muscle layers to either the oesophagus or the spinal canal where the larvae stay dormant during winter. in later winter or early spring the larvae migrate to the tissue under the skin on the back where they mature for about 30 days. the larvae then drop off the host animal and pupate in the soil.


What are the two species of warble fly?

Hypoderma bovis and Hypderma lineatum.


Which human disease is BSE linked to?

BSE was linked to a new varient form of the human TSE, Creutzfeld jacob disease.


What are the typical clinical signs of BSE?

changes in mental state, abnormalities of posture and movement and of sensation. The clinical disease usually lasts for several weeks and it is invariably progressive and fatal.


What is scrapie?

A fatal brain disease of sheep and goats, not known to pose a risk to human health. Most affected animals are infected through exposure to scrapie infected sheep and their environment. the incubation period can be a number of years. Disease is most commonly seen in animals between two and five years old and cases generally appear singly.


What are the typical clinical signs of scrapie?

Occurs most commonly between 2-5 years of age. The onset is insidious and frequently subtle. Affected animals usually show a combination of clinical signs: skin irritation, behavioural changes, changes in posture and gait, with later clinical signs of weight loss and death.


What is the cause of sheep scab? what is the life cycle of this?

The parasitic mite - psoroptes ovis. the female mite lays one or two eggs daily in the fleece of sheep for about 40 days. Larval mites hatch from eggs and go through various development stages to become adults after about two weeks. Mites can exist off the sheep and remain infective for up to 16 days. Fence posts used for rubbing, handling facilities, trees, bushes, livestock transporters, shearing equipment and contaminated clothing can be sources of infestation and remain so for a considerable period. The mites feed on the surface of the skin.


What is the cause of bovine tuberculosis and what animals does TB infect?

Mycobacterium bovis - which can also affect badgers, deer, goats, pigs, camelids and occasionally dogs and cats. Bovine TB is also a zoonotic disease causing a condition very similar to human TB.


What are the key measures for controlling TB?

Cattle surveillance to address cattle to cattle transmission. promoting good biosecurity. Control of TB in badgers. Measures to tackle TB in non bovine farmed species. Advice and support for farmers. TB eradication group for england. Culling and vaccination of badgers in areas of high incidence of bovine TB.


How is testing for bTB done?

Single intradermal comparitive cervical tuberculin test . All herds are subject to regular routine testing. Herds in high tb areas are tested anually. Scotland is officially tuberculosis free. Scotland testing is once four yearly. Pre moving testing is a statutory requirement and post movement testing is also carried out 60 days post movement from high inident area.


Which animals are NOT fit to be transported?

Unable to move independently or walk unassisted,
have a severe open wound or prolapse,
pregnant females for whom 90% of gestation has passed, or females who have given birth in the previous week, new born mammels in which the navel has not completely healed, pigs of less than three weeks of age, lambs less than one week of age, and calves less than ten days of age, unless transported less than 100km, dogs and cats less than eight weeks of age, unless accompanied by mother, deer in velvet. Sick or injured animals may be considered fit for transport if slightly injured and transport would not cause additional suffering or transported for veterinary treatment.


What is the longest journey time allowed for poultry?

suitable food and water to be provided at intervals, except for journeys under 12 hours or over 24 hours for chicks hatched within previous 72 hours.


Where is the best source of virus when diagnosing foot and mouth?

Vesicular epithelium


What are the PM lesions seen with bluetongue?

Catarrhal inflammation and haemorrhages of Gi tract, haemorrhages in and on the heart, gelatinous red fluid in subcut tissue and within muscles. Lung congestion and oedema. Bronchopneumonia.


What are the presenting signs of anthrax?

Sudden death. blood from nostrils, blood in faeces. colicky pains, dejection, loss of milk if seen alive.
In pigs and horses - hot painful swelling in the region of the throat. In horses, symptoms of acute colic are seen.
Unopened carcasses may be swolen and blood may ooze from nostrils or other orifices.
Any sudden death in farm stock should always raise suspiscion of anthrax.


What antibiotics can be used to attempt to treat anthrax if animals are seen alive?



What stain is used to diagnose anthrax?

Methylene blue


What is enzootic bovine leukosis?

A retrovirus that causes leukaemia and multiple tumours in cows. Clinical signs usually become apparent between 4-8 years of age, rarely seen in animals under 2yo. Chronic ill health, progressive loss of condition, weakness, anaemia. Lymphocytosis is not a constant feature but when it does occur it is presumptive evidence of infection. The findings of any tumourous changes in bovine carcase must be considered suspiscious of EBL and samples submitted to APHA.


What testing must be done before movingcattle from high risk TB areas?

Pre movement testing is a statutory requirement: cattle 42 days old and over moving from high risk areas must have tested negative to a btb test within 60 days prior to movement. Post movement testing is also carried out 60 days post movement from high incidence areas.


What are the clinical signs of african horse sickness?

High fever, severe respiratory distress, subcutaneous oedema of head especially supra orbital fossa, also neck, abdomen. Zebras are the autral reservoir of infection. infection is maintained by culicoides and prolonged viraemias in infected mammals. Causes massive hydrothorax and pulmonary oedema, haemorrhages in the heart, stomach.