DISEASES OF THE NERVOUS SYSTEM AND THE SKIN IN SWINE Flashcards Preview

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Flashcards in DISEASES OF THE NERVOUS SYSTEM AND THE SKIN IN SWINE Deck (80)
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1

Rabies

Extremely rare
Hungary is free
Notifiable,
Zoonosis
Lyssavirus
Free range/contact with wild animals (fox) is the most common cause.

2

Rabies: Clinical signs:

Fever
Salivation (most typical)

Nervous signs:
Aggressivity
Anorexia
Head pressing against wall
Ascending paralysis (weakness of the hindquarters!)
Depression,
Vocalization – very disturbing

3

Rabies: Lesions:

Lest severe is cortex < brainstem < spinalcord (most severe)
Non-suppurative encephalomyelitis
Perivascular white blood cell (lymphocytes, plasma cells, macrophages)
Diffuse or multifocal gliosis
Neuronophagia
Haemorrhages
Vasculitis in the grey matter

Suspect the disease, ask for help!

4

Aujeszky’s disease:

Rare, Hungary is free, notifiable
Herpesvirus (SHV-1) – carriers long-term
Contact with infected animals (wild boar),
Aerial spread (3 km, up to 5km), mechanical vectors(?)

5

Aujeszky’s disease: clinical signs

First outbreak in a naive herd: (most common in Europe)
Up to 20% of non-nursing sows: abortions, early farrowings, no new farrowing, birth of dead or weak piglets, disruption of the normal cycle (all stages)
Diff. diag.: ASF, CSF (African and classical swine fever – same reproductive consequence)
(CATS!! – lethal, if they eat piglet)

Piglets (<3 weeks): anorexia, vomiting, diarrhea, respiratory signs (common), incoordination, Seizures
Older animals: fever, anorexia, respiratory signs, seizures, blindness

6

Aujeszky’s disease: clinical signs in Chronically infected herds:

Chronically infected herds: decreased reproduction parameters, occasional birth of mummified, dead or weak piglets (young sows), not proper cycles. (diff. diag.: PRRS)
Recognize it, ask for help! Farm need to lock down and culling of animals.

7

Teschen disease (Talfan):

Rare, notifiable in Hungary
Teschovirus (PTV)
Ccontact with contaminated equipment, vehicles, or infected animals

8

Teschen disease (Talfan): pathogenesis

intestines – bloodstream – nervous system
Enterovirus – survives good in environment.

9

Teschen disease (Talfan): Clinical signs:

First outbreak in a naive herd:
In all age groups (most common in weaned piglets and growers)
first off-feed, starts getting depression and FEVER.

Then later they start staggering, ascending paralysis
( first hind hooves, thighs, pelvis, lumbosacral region in the end)
NO FEVER AT THIS POINT!!

Then opisthotonus, nystagmus, complete paralysis is possible if the respiratory muscles are still operating.
Most animals dies when respiratory muscles are affected.
Polioencephalomyelitis, lymphocytic perivascular infiltration (in spinal cord!!)

Only motor nerves are affected, sensory ones are functional (hyperestesia). So the animals feels everything that happens.

They have to be culled after two positive tests. And then the bodies should not be cut in the spinal canal. Do not halve carcasses in the mindline!

Recognize the disease, ask for help!

10

Streptococcus suis:

Zoonosis
Present in the tonsils, risk factors (regrouping, vaccinations, treatments, PRRS) facilitate the clinical disease
Haematogenic spread, spreads into the heart, respiratory system, nervous system and joints are affected.
Real treat to veterinarians and farm workers.

11

Streptococcus suis: Clinical signs:

In predominantly weaned piglets:
-Sudden death often happens
-Many shows meningitis: anorexia, blotched skin, fever, depression, staggering, lameness, paralysis, swimming, opisthotonus, tremors, seizures, blindness, deafness.
-Pericarditis in small piglets

Sows:
-Decrease in reproduction
-Birth of dead piglets


2-4weeks to fattening pigs:
-Respiratory signs
-Pneumonia (PRRS,B.bronchiseptica,M. hyorhinis predisposes)

12

Streptococcus suis: treatment

Usually not treated because of the damage it does.

Individual: Before nervous signs, if the animal have nervous signs euthanasia is the only option.
Piglet–penicillins , fluid therapy

Herd: AB before regrouping, replace herd.

13

Haemophilus parasuis (Glässer’s disease):

Lives in the upper respiratory tract
Appears with the disappearance of maternal immunity, it can spread haematogenic and attack other serous membranes.

14

Haemophilus parasuis (Glässer’s disease): clinical signs

Appear in animals 4 to 8 weeks old ( this is when the maternal immunity disappear)
-Sudden death (septicaemia)
-High fever,coughing, abdominal breathing caused by pleuritis.
-Arthritis

Nervous signs: recumbency, swimming, tremors, seizures that come from meningitis.

Chronic: adhesions of all serous membranes – losses at slaughter.

15

Haemophilus parasuis (Glässer’s disease): lesions

Septicaemia, pleuritis, peritonitis, pericarditis, arthritis, meningitis on serous membranes.

16

Haemophilus parasuis (Glässer’s disease): treatment

Usually not treated, impossible because of rapid losses.

Can use penicillins, ceftiofur, enrofloxacin, tiamulin, potentiated sulphonamids – whole group or individually.
If we catch it early, if the disease has started we can’t do anything.

Preventive AB: can be effective, not recommended (EU) of the whole group of piglets.

17

Bowel edema (oedema disease):

Verotoxin producing E. coli (O138, O139, O141)
Rare disease because of newer farming.

Bacterium attaches itself to the intestinal wall, produces toxin (maternal IgA prevents disease, infection after it disappears), toxin is absorbed if the maternal immunity disappears, causes edema in the gastric and intestinal wall and blood vessels in the brain.

18

Bowel edema (oedema disease): clinical signs

1 to 4 weeks after weaning
-Sudden death(bestpiglets)
-Nervous signs: Staggering, incoordination, swollen eyelids, high-pitcheds queeling, anorexia, lameness, partial paralysis, fits, seizures, difficulty breathing.

19

Bowel edema (oedema disease): treatment

-Usually not successful with AB, because E.coli has a short life.

Prevention:
-Protect the piglet.
-Clean environment
-Early weaning!
-Restrict feed after weaning or increase fibre content on the expense of the starch content since the bacteria multiply in the starch.
-Replace sensitive herd

20

CONGENITAL TREMORS

Also called; Myoclonia congenita, shaking piglet, dancing pig disease
It is in newborn piglets.
Rhythmic, uncontrollable muscle tremors, milder in rest.

21

CONGENITAL TREMORS - types

Based on the histopathology lesions in the CNS
A– (5 types) hypomyelinogenesis detectable
B – no lesions visible

22

A 1

Always a result of swine fever
-Infection between day 10 and 50 of pregnancy (when nervous system develop)
-Still problem in south america and Africa.

Cerebellar hypoplasia and dysplasia, spinal cord hypoplasia
-Cerebellum/whole brain weight: <10% - detection!

Spinal cord hypomyelinogenesis
-Can affect sows of all ages, both genders of piglets, high mortality
-Disease (swine fever) in other age groups, presence of virus.

23

A2

Other, not yet identified virus infection
- PCV-1, PCV-2(circo), enterovirus? these are suspected.

-Can cause hypomyelinogenesis, cerebellar weight normal
-affects gilts’ litters of all gender.
-piglets of both genders can be affected, morbidity up to 80%, low mortality
-diminishes by week 8
-most cases belong here, this is the most common type.

24

A 3

Male piglets of Landrace and its crosses
Hereditary disease
High mortality
Causes hypomyelinogenesis, abnormally few oligodendrocytes in the brain.

25

A 4

Belted breeds and there crosses
Causes hypomyelinogenesis, lipid content of the myelin sheath is 50% of the normal value, will cause functional problem.

Autosomal recessive trait - 25% of the litter is affected
-high mortality
-both genders
-sows of all ages can be affected

26

A 5

Very rare!
Organophosphate exposure around day 45 to 63 of pregnancy.
Only Spinal cord and/or cerebellar hypoplasia are effected
Causes hypomyelinogenesis
Both genders of piglets, all ages of sows
up to 90% morbidity - high mortality

27

B

No histopathological lesions
Functional disorder of the nerves of piflets
Cause unknown

28

Salt poisoning:

-Problem with the water supply, high salt content in feed
-Normal salt content 0,4 to 0,6%, pigs can tolerate up to 2% if water supply is adequate
-Small farms often have this problem, leftovers and homemade food.

29

Salt poisoning: clinical signs

24 to 48 hours after exposure.
24 to 48 hours after the disruption of the water supply
Pigs try to drink from the drinkers repeatedly, unsuccessfully

-Aimless wandering (blindness?)
-Symptoms of meningitis
-Head pressing against wall
-Nose twitches before a seizure starts

30

Salt poisoning: treatment

By the time clinical signs are present it is ussally not succesful
-Slow rehydration (po.,perrectum,ip.) route depend on size of animal.