PIg musculoskeletal

Question 1

When is splay leg most commonly an issue

Answer 1

In premature piglets e.g PRRSV outbreak causing early farrowings

Question 2

What infectious agents are associated with joint ill (arthritis in suckling pigs)

Answer 2

strep suis (1), staphylococcus, T pyogenes

Question 3

What primary infectious agents are associated with arthritis in weaners and growers

Answer 3

• Glasserella parasuis
• Erysipelas rhusiopathiae
• Strep suis type 1, 2, 14
• Mycoplama hyorhinis

Question 4

What pathology is found with glasserella parasuis

+what about in the survivers of the septicaemia

Answer 4

 Polyserositis: arthritis, pleurisy, pericarditis, peritonitis
Survivors develop chronic arthritis, heart failure +/- intestinal obstruction

Usually fatal

Question 5

Wht would we suspect is the issue if we see some lameness and coughing, some septicaemia

Answer 5

Glasserella parasuis

Question 6

What do we need to remember about Erysipelothrix rhusiopathiae

Answer 6

Zoonotic
Farms near poultry farms are at much higher risk

Question 7

3 forms of erysipelothrix rhustipathiae infection

Answer 7

1) Peracute; sudden death due to overhwelming septicaemia, flushed skin
2) Acute = diamond skin lesions from septicaemia, high fever
3) Chronic; congestive heart failure from endocarditis, lameness due to arthritis

Question 8

Pathological findings wih erysipelothrix rhusipathiae

Answer 8

fibrinous excessive joint fluid, polyarthritis, cartilage erosion etc, valvular vegetative endocarditis in heart, petechial haemorrhages in kidneys

Question 9

What can we use to treat erysipelothrix rhusiopathiae and when is it more effective (acute or chronic)

Answer 9

Penicillin
More effective in acute

Question 10

When might we choose to vaccinate growers as well as breeders against erysipelothrix rhusipathiae

Answer 10

In high risk outdoor farms e.g with turkey contact

Question 11

When do we vaccinate piglets for strep suis

Answer 11

A bit after weanign as maternal antibody can interfere with vaccine response

Question 12

What is the key predisposing factor for strep suis

Answer 12

Stress and inadequate colostral protection

Question 13

When do we typically see disease with strep suis

Answer 13

2-6 weeks

Question 14

What type of diseases can mycoplasma hyorhinis cause

Answer 14

polyserotitis, arthritis, otitis media, pneumonia
= low mortality

Question 15

Where do we take a sample to diagnose mycoplasma hyorhinis

Answer 15

From non-respiratory locaition since it is common non-pathogenic inhabitant on nasal cavity

E.g sample joint for PCR analysis

Question 16

What is the common cause of arthritis in finisher pigs

Answer 16

mycoplasma hyosynoviae
- PIglets exposed young by dams but closotral antibodies last to around 10-12 weeks so see disease then
Or see lameness in newly purchsed breeding stock esp since stressful

Question 17

Clinical signs of arthritis in finisher pigs and what do they look like on PM

Answer 17

dog-sitting, shifting weight, minimal swelling, 10-12% become chronic

Diagnosis: clear yellow/brown joint fluid containing fibrin, proliferative inflammation of synovial membrane, articular surface normal + confirm by PCR

Question 18

What is the aertiology behind bursitis

Answer 18

hard floors, high stocking densities, wide slats, heavy pigs

= common; seen as a -ve welfare outcome on assurance schemes

Question 19

WHat is a carpal hygroma

Answer 19

accumulation of fluid following trauma with formation of bursa in carpal region

Usually not lame but seen as a -ve welfare outcome

Question 20

What is the aetiology of porcine stress syndrome

Answer 20

Where there is an inherted depect mutation in RYR gene which causes Ca2+ release channel in SR to open at lower threshod

Linked to pletrain pedigree breed and heavy muscling

Question 21

Which 4 conditions are related as part of porcine stress syndrome

Answer 21

1) porcine stress syndrome
2) Malignant hyperthermia
3) Pale soft exudative pork
4) Back muscle necrosis

Question 22

What is malignant hyperthermia

Answer 22

When pigs have massive muscle contraction upon exposure to halothane causing temp rise, vasodilation, hypovolaemic shock, cardiac dysrhytmia and death

Related to RYR mutation

Question 23

Which gene is affected in porcine stress syndrome

Answer 23

Hal gene

Question 24

What is pale soft exudative pork

Answer 24

= active glycolysis at slaughter so pH of muscle falls while still warm
 Meat loses colour, water holding capacity
 Exacerbated by stress pre-slaughter; those w Hal mutation more susceptible

Question 25

What is back muscle necrosis and what factors are involved

Answer 25

= necrosis of parts of longissimus dorsi muscle, pain and swelling over affected area

RElated to vit E/selenium deficiency and worse with RYR hal mutation

Question 26

What are the signs of porcine stress syndrome

Answer 26

tremors, dyspnoea, hyperthermia, blotchy skin, collapse, death, hot ambient temperature

Trigger = stress e.g in transport must be careful

Question 27

Osteochondrosis aetiology

Answer 27

Incomplete cartilage ossification at growth plates
- RElated to genetic selection for rapid growth
Can also be caused by inadequate diet balance (Ca2+, phosphate, protein), restricted movement etc

Question 28

Clinical signs with osteochondrosis

Answer 28

[up to 30% clinical] leg weakness, reluctant to stand, dog sitting, crossing hind legs, shortening steps

Question 29

Where do we see dyschondroplasia with osteochonrosis and what age pigs does it affect

Answer 29

Pigs <18 moths
Fermoal condyle of stifle, ulna growth plates, femur prox growth plate so can get femoral head separation (epiphyseolysis), costochondral junction

Question 30

What is epiphysiolysis

Answer 30

Where there is long term instability ot femur/hip joint due to osteochonrdosis and get shearing off of the femoral head at the growth plate (which is incompletely ossified) manifesting in sudden hind limb lameness

Question 31

IF a pig presents acutely hind limb lame and the affected leg is shorter what has happened

Answer 31

Epiphysiolysis; shearing off of the femoral head at the growth plate

Question 32

Which secondary bacteria are involved in pedal sepsis

Answer 32

F necrophorum, T pyogenes, spirochaetes

Question 33

Prevention of pedal sepsis

Answer 33

hygiene and floor maintenance, adequate biotin in ration, careful monitoring for early lameness and erosions

Question 34

What is teh aetiology of pedal sepsis

Answer 34

Primary lesion in wall/hoof due to abrasive bedding or flooring or cracked claws
Then colonisation y secondary bacteria (F necrophorum, T pyogenes, spirochaetes)

Question 35

What is white muscle disease; presentation and cause and diagnosis

Answer 35

Due to vit E/Se insuficieny in feed
See swelling of back muscles, ataxia, muscle tremor

Treat with VitE/Se injection and diet review

ALso called back muscle necrosis; predisposition from procine stress syndrome

Diagnosis: low Vit E in liver, histology showing myofibrillar degeneration, cinical signs and heart lesions

Question 36

WHat is absolute vs increased demand vit E/Se deficiency

Answer 36

 Absolute: e.g where spoilt grain causes oxidation of Vit E
 Increased demand: e.g pigs fed lots of poly-unsaturated fatty acids in feed

Question 37

What is kyphosis

Answer 37

Dyschondroplasia in vertebral bodies due to insufficiency of phosphate and balance with calcium in rapidly growing pigs

Get curved back

Question 38

Signs of biotin deficiency

Answer 38

 Pathology = necrosis in stratum corneum of epithelium
Signs: alopecia, dry scaly skin, can progress to dermatitis with secondary infection + increased erosion and susceptibility to cracks in hooves, reproductive issues

Question 39

What are barley and wheat low in that related to the skin

Answer 39

biotin