Pigs Flashcards
Average weaning, growing and finishing weight of UK pigs?
Weaning: 7kg
Grower: 30kg
Finisher: 130kg
Types of pig farms?
Farrow to finish
Store pig producer
Weaner producer
How good are pigs’ senses?
Smell - very good
Sight - not great in bright light, can’t see red
Touch - most touch receptors on snout, may not feel piglets if lie on them
Hearing - good at hearing low grunting sounds and high pitch sounds e.g. screaming
Why are batch systems used for some pig farms?
Splits up age groups
Reduces endemic infection seen in continuous production
Which are the main diseases that can be vaccinated against in a pig breeding herd?
Parvovirus Erysipelas PRRS PCV2 Leptospirosis Clostridium novyi
Which are the main diseases that can be vaccinated against in a pig growing herd?
Mycoplasma hyopneumonia (EP) PCV2 PRRS Haemophilus parasuis (Glassers) Lawsonia intracellularis Erysipelas Actinobacillus pleuropneumonia (APP) E.coli Salmonella typhimurium (autogenous vaccine)
Types of vaccines? Pros and cons?
Inactivated - slow, lower response, safe, cheap
Live - quick, strong response, risky
Autogenous - emergency only
Methods of administration of vaccines in pigs?
Injection - SC, IM, ID
Oral
Water
What can affect the effectiveness of a vaccine?
MDA interference (can last up 6 weeks post weaning?) Duration of protection variation Infection pressure vs immune protection
What are autogenous vaccines?
For emergencies
Agent isolated on farm - named farm specific
Can only be used if commercial vaccine not available or proven not effective
All inactivated
Advantages and disadvantages of injectable medications for pigs?
Quicker response Easier identification Ensures correct dose Individually administered Time/labour intensive Potential injection site issues Stress factor Broken needles
Advantages and disadvantages of medications in water for pigs?
Easy to administer - no stress Quick start of medication Intermediate cost Group treatment - reduced targeting Not guaranteed uptake Plumbing/blockages Cost of wastage
Advantages and disadvantages of medications in food for pigs?
Whole groups treated Least cost per treated animal Variable dose Slow start of treatment Reduced targeting of ill animals - least effective method for ill animals Residue risk Logistics for small quantities
How long to medical records need to be kept for? What information is needed for pigs?
5 years Product used and batch Treatment start and end dates ID of animal Treatment reason (not legal requirement but is for red tractor) Dose given and route Withdrawal period Clearance date Initials/name of person giving the medication
Main route of antibiotic administration in pigs?
In feed
What are the 3 classes of antibiotics?
Class 1 - standard prescribing within responsible use guidelines
Class 2 - not to be used unless sensitivity tests or clinical experience has proven that first choice ABs are not effective or available
Class 3 - products of last resort, only to be used when no other options available and supported by lab sensitivity tests or in extreme circumstances when all else has failed
What affects choice of antibiotic?
Sensitivity Clinical experience Availability and deliverability on farm Speed of delivery Withdrawal period
Which antibiotics are low penetration? What not good for?
Beta lactase
Aminoglycosides
Not for CSF, milk or transcellular
Which antibiotics are medium-high penetration?
Sulphonamides
Trimethoprim
Macrolides
Tetracyclines
Which antibiotics are high penetration?
Higer tetracyclines
Fluoroquinolones
Florfenicol
How to calculate a group dose of medication for pigs in food/water?
Water: pigs consume about 10% BW daily
Feed: often calculated as ppm for finished feed
Which coccidiostat is used for pigs?
Toltrazuril
What drugs are used in pigs for farrowing assistance and uterine contraction/milk let down?
Induction - PGF2a
Uterine contraction/milk let down - oxytocin
How are progestogens used in pigs?
Oral dose for 18 days
Oestrus seen 5 days after the last dose
Ovaries must be active
Under dosing is catastrophic
How long is a pig oestrus cycle?
21 days (19-23)
BCS 1-5 of pigs?
1: emaciated sow backbone very prominent
2: thin, backbone prominent
3: ideal condition during lactation and at weaning, backbone just palpable
4: slightly overweight, cannot find backbone
5: body rotund, over fat
What is the maintenance feed for dry sows? When is more needed?
2.5kg
More for wearers, service/implantation, late pregnancy
Timing of mating for pigs?
Ovulate 2/3 way through standing heat
Late standing heat: Day when first boar test positive
Normal standing heat: 1 day after first boar test positive
Early standing heat: 2 days after first boar test positive
Signs of heat in pigs?
Vulva - reddening, swelling, mucous Vocalisation Interest in boar Flank nosing Smelling of boar Standing next to boar Standing to back pressure Allowing sows or boar to mount
Features of a good AI area?
Close to sows Not near boars Nose to nose contact Individual insemination pen Undisturbed area post insemination Flow of pigs Good gates/dividers
Which parities of pigs are most productive with number of pigs born alive?
4-5
What is the maximum farrowing index?
Total sow cycle = 21 weeks
So 52/21 = 2.476
Influences on farrowing index?
Conception rate Final farrowing rate Weaning to service gap Weaning to actual conception gap Other causes of empty days
Influences on piglets born alive?
Point ov ovulation Point of fertilisation Ability to implant Ability to maintain through pregnancy Survival through farrowing
When are piglets weaned and when are sows then served again?
Weaned at 4 weeks
Served 1 week after weaning (5 weeks after farrowing)
General targets for total born/litter, born alive/litter, born dead/litter, born mummified/litter, conception rate, farrowing rate and farrowing index for pigs?
Total born/litter: > 12.5 Born alive/litter: > 11.5 Born dead/litter: < 0.7 Born mummified/litter: < 0.3 Conception rate: > 90% Farrowing rate: > 85% Farrowing index: > 2.3
Non infectious causes of decreased fertility on pig farms?
Nutrition Stress - physiological behavioural, heat, cold Quality of service and implantation period Staff factors Seasonal infertility Herd profile Sunburn/sensitisation Mycotoxins Sow/boar illness - lameness
Infectious causes of decreased fertility on pig farms?
Porcine parvovirus PRRS PCV2 Swine Influenza Leptospirosis SMEDI viruses
Aujeszky’s
Classical Swine Fever
Brucella suis
Systemic infections causing pyrexia
Endometritis
Orchitis
Conception issues in pigs?
Silent heats not seen
Gilts - age, weight, heat balance, genetics, intersexuality, abnormal anatomy
Sows - energy balance, stress, lactational oestrus, seasonal, mycotoxins
When are late returns classed as abortions?
> 11 weeks in pig
Causes of regular returns of pigs?
Common - fertilisation has failed to occur
Timing of service
Quality of service
Boar contact post AI service
Boar/semen problem
Or early loss of embryos - incomplete involution, stress, nutrition, infection
Irregular returns?
Less common
Ultrasound PD valuable to know if actually been in pig
Embryo loss >12d
Infection - tracking endometritis
Types of returns to service?
Regular - multiples of 21d
Irregular - our of sync
Late returns (abortions) - > 11 weeks in pig
Prevention of endometritis in pigs?
Service, post service and farrowing hygiene!
Causes of a reduced litter size in pigs?
Ovulation issue - genetics, nutrition, age, parity structure
Fertilisation issue - service timing, semen quality, boar/semen issue, nutrition, stress
What can disrupt implantation of pregnancies in pigs?
Stress is biggest issue
Nutrition
Seasonal influence
Disease
When are pig pregnancies more robust?
After 30d
Causes of abortions in pigs?
Stress Parvovirus PRRS PCV2 Erysipelas Leptospirosis
Aujeszky's CSF Toxaemia - endotoxins, plants, mycotoxins Systemic pyrexia Placentitis
What are the aims during farrowing?
Increase the number of live pigs weaned
More even litters
Increased average weaning weight
Avoid excessive loss of sow condition
What signs suggest a sow is close to farrowing?
Nesting behaviour
Discomfort
Decreased appetitte
Milk appearance in last 12hr
Signs of dystocia in pigs? How common
No piglet for >30minutes
Straining
Rare as multiparous with small foetuses
Causes of primary inertia in pigs?
Overconditioned Lack of muscular tone Hypocalcaemia Concurrent illness Endocrine malfunction
Causes of secondary inertia in pigs?
Exhaustion
Dehydration
Excessive heat
Prolonged obstruction (hypocalcaemia) often gives follow up problems
Causes of foetal dystocia?
Obstructions are rare Coiled uterus -> backup of foetuses Oversized usually in small litter numbers Congenital abnormalities Putrefying dead foetus Malpresentations very rare
Farrowing problems?
Dystocia Uterine twists Operator induced - uterine ruptures, pelvic/vaginal damage Collapsed/narrow pelvis Everted bladder/vaginal prolapse Oxytocin overdose
How to get piglets out if needed?
Fingers in eye sockets or jaw to pull
Use of baler twine useful if pelvis is tight
Treatment drugs for farrowing problems?
Oxytocin once clear (lasts 30mins)
Antibiotics if assisted or retained piglet/membranes (penicillin)
NSAIDs (anti-inflammatory and analgesia)
Calcium - SC, not clear cut benefit
PGF2a - induction (careful) or post farrowing for retained
When are caesareans indicated in pigs? Drugs needed? Procedure?
If totally unresponsive to inertia or obstruction
Sedation - azeperone (licensed, need to leave alone for 20 mins) or xylazine/butorphanol (not great sedation)
GA - ketamine
Local - possible but complicated
Flank incision either side ~10cm above udder and cranial to hindleg
Extend for 20-25cm
Difficult to manipulate opposite uterine horn but persevere
Euthanasia and hysterectomy an alternative
Prolapses at/post farrowing?
Rectal - can replace if fresh, otherwise will resolve with time
Vaginal - often able to work through if assisting
Uterine - enormous, difficult to replace, take time and be patient if attempting, can remove but often euthanasia carried out once colostrum has been obtained
Importance of milk?
Colostrum
Total weaning weight of litter is linked to total milk production
Total milk production is linked to total food intake during lactation
In what way do pigs let milk down?
Intermittent milk let down
Low grunting to call piglets
Piglets find teats and push on them - increases oxytocin
Milk let down for 30-45 seconds
Repeats about about an hour
Dominant sow will start and then others will do same
What is MMA syndrome?
Mastitis, metritis, agalactia
Management in origin
Not all parts always seen
Environment - temperature, floor quality, wetness
Nutrition - prefarrow excess, constipation
Water availability
Why must pig milk be monitored?
Milk production can easily be lost and does not return
Cross fostering/supplementation important
Nutrition has an enormous influence
Can have infection
Treatments for milk problems in pigs?
Steroids - allows milk to flow
Oxytocin (or carbetocin as lasts longer)
Broad spectrum Abs - penicillin/streptomycin
What is the definition of still born piglets?
A piglet that has died in the 24hrs before farrowing?
When do the majority of piglet deaths occur? Most common cause?
<72h
Overlays
Piglet routines?
Iron injections Tagging/notching/tattooing Tail docking Teeth reduction Injections - vaccines/treatments Oral treatments
Causes of piglet scour?
Milk/nutritional scour
Viral - rotavirus, PED/TGE, PRRS
Bacterial - E.coli, Clostridium perfringens
Parasitic - Isospora suis, Cryptosporidiosis, Strongyloides
Risk factors for piglet scour?
Poor hygiene
Lack of colostrum
Fostering
Gilt/sow illness
When is milk scour seen? Why does it happen?
Either very early on or from 3 weeks of age
GIT overload to large intestines
Self limiting
Clinical signs of piglet scour caused by viruses? Why do they cause scour?
Hugely profuse amounts of watery scour Very early onset Mortality is related to dehydration Small intestinal villous atrophy Secondary bacterial infection Difficult to directly treat (increase hygiene and immunity)
What type of virus causes PED and TGE? What do they stand for? Pathogenesis? Clinical signs? Age affected? Treatment and control?
Coronaviruses:
- Porcine epidemic diarrhoea
- Transmissible gastroenteritis
Pathogenesis:
- Infect and damage gut epithelial cells, especially damage to villous structure
- High morbidity and mortality
Signs:
- Profuse watery scour with vomiting of piglets
- New PED has very high mortality under 3 weeks old
- Affects all ages and can be self limiting but can persist in larger herds
TGE:
- acute, productive diarrhoea -> high mortality
- can cause diarrhoea and vomiting in older sows
- sows can develop protective IgA mediated immunity and virus may persist well in herds
- survives well at low temperatures - winter outbreaks common
- no treatment for piglets
- high biosecurity and closed herds reduces risk
No vaccine or direct therapy
(vaccine available in some countries but efficacy unclear)
Clinical signs of PRRS in piglets?
Dyspnoea CNS signs Weak Conjunctivitis Bruising Anaemia Scour, sometimes containing blood High mortality
When is E.coli scour usually seen in piglets?
Usually within first week but can be any time during lactation
Clinical signs of E.coli scour in piglets?
Watery scour often present Can be flocculant/creamy No vomiting usually More common indoors Chilled arcs can predispose outside
Treatment for E.coli scour in piglets?
Speedy treatment essential
Hydration
Antibiotics based on sensitivity - apramycin, spectinomycin
Vaccination of breeding herd - short term cover via colostrum
Dry disinfectant powders
Probiotics
What does Clostridium perfringens type C cause in piglets? Treatment?
Sudden death within 24 hours due to acute haemorrhagic enteritis
Produces B toxin
Usually seen outdoors
Can only be treated pre-emptively at birth (metaphylaxis)
Penicillins usually effective
Longer term vaccines should be used
What does Clostridium perfringens type A cause in piglets? Treatment and control?
Mainly associated with low grade chronic diarrhoea
Pasty scour any time during lactation, giving poor growth
Produces a and B2 toxins
Difficult to control and treat
Penicillins may work but variable
Maintain hydration
Prevention - short term metaphylaxis or use ruminant vaccination
Clinical signs and age of piglets affected by Coccidiosis? Treatment and control?
Usually 10-21d old with pasty yellow loose faeces
Resolves at weaning but huge impact on weaning weight
Does not respond to treatment
Hygiene main method of control
Toltrazuril at 4do can resolve clinical impact
Why does Isospora cause disease in piglets?
Found within the gut wall
Caused physical damage to the lining
Most common nervous disease of piglets? Method of transmission? When seen?
Bacterial meningitis
Streptococcus suis, E.coli, Haemophilus parasuis
Often due to bacterial penetration through ‘openings’ - navel, wounds, teeth clipping, tail docking
Sometimes also seen with joint ill
Can affect any age during lactation but usually nearer to weaning
Clinical signs of bacterial meningitis in piglets and weaner?
Nystagmus Opisthotonus Trembling Pyrexia Collapse Paddling Convulsions Sudden death
Treatment and control of bacterial meningitis of piglets?
Treatment must address swollen brain - steroids quickest, along with systemic antibiotics
Hydration important
Control with good hygiene and colostrum management
What are the different forms of congenital tremors in piglets?
A1: cerebellar atrophy, CSF infection
A2: cerebellar atrophy and hypomyelinogenesis, pestivirus infection
A3: Landrace inherited to male pigs
A4: Saddleback recessive inherited defect
A5: cerebellar atrophy and hypomyelinogenesis, organophosphate effect
Clinical sign of congenital tremor type A2 in piglets? When most prevalent? Impact?
Intention tremor that occurs sporadically
Often more prevalent in gilts or new herds
Recovery often occurs naturally as long as they can suckle
Splay leg piglets can be seen
Main causes of lameness in piglets?
Joint ill - often associated with bacteraemia from an ‘opening’, prompt treatment can resolve, control with hygiene
Splayleg - variable onset and cause, can be supported to enable suckling
Injuries - caught toes may be common on certain floors, injuries from mum
Other congenital abnormalities of piglets?
Cleft palate Epitheliogenesis imperfecta Hydrocephalus Contracted tendons Monsters
What is the legal minimum for age of weaning of piglets?
28 days
21 days if specifically going into weaning specific accommodation which is all in all out
Targets for number of piglets weaned/sow, weaning weight and weaned weight/sow?
Weaned/sow > 11
Weaning weigh > 7kg (28d)
Weaning > 100kg/sow
Features of weaner food?
High milk protein content - goes off quickly so need to make sure it’s fresh
What are the main things that go wrong with weaner pigs?
Too young/small Failure of gut development Hypothermoia Infection pressure too high Stress - space, allowances Loss of condition - tucked in Navel sucking Vices
Prevention of poor weaning pigs?
Suitable pigs into correct accommodation
Proper food
Same age group
Interfere as little as possible
Causes of poorer pigs from farrowing?
Continuing damaged gut - Coccidiosis)
Lowered weaning weight - E.coli, Rotavirus, Clostridia
Joint ill - inadequately managed
Triggers of gut problems in weaner pigs?
Dietary and feeding changes Temperature changes Draughts Inadequate hygiene Overeating Historical GIT damage
When does E.coli affect weaner pigs? Clinical signs? Which part of the GI tract does it affect?
Sudden onset of watery scour around 1 week post weaning
Loss of condition - dehydration
Mild pyrexia and can cause some sudden deaths
Affects distal SI
Treatment and control for post weaning E.coli in pigs?
Swift treatment needed Water medication simple and effective Antibiotics - apramycin, neomycin, spectinomycin Hygiene important Vaccination if appropriate Zinc oxide in feed Acidification of water
Salmonella enterica in pigs: Which species? What does it cause? Risk to humans?
Clinical signs, control and prevention of Salmonella affecting weaner pigs?
Main serovars in UK are S typhimurium and S derby:
- Infection can range from severe to mild inflammatory gastroenteritis or be carried asymptomatically in gut or mesenteric LNs (zoonotic risk)
- S typhimurium: emerging drug resistant variants particular challenge
S cholerasuis:
- Adapted to pigs and may cause invasive necrotic enteritis or septicaemia (typhoidal disease)
- Rrare in UK
- Can be zoonotic and highly invasive in humans
Transmission:
- Resilient so persists well in environment
- Transmission from carrier pigs
- No current vaccine for pigs
Diagnosis:
- Culture of faecal material on selective media e.g. brilliant green
- Typing
Signs:
- Low grade scour: indistinguishable from E.coli
- High mortality necrotic enteritis form more obvious clinically
- Distal SI and LI affected
Treatment:
- Aggressive treatment to be effective
- Antibiotics
Prevention
- Water acidification can be best hygiene
- Probiotics may reduce transmission
- Good management and hygiene
Nervous diseases of weaner pigs?
Bacterial meningitis Oedema disease Water deprivation Middle ear disease Toxicities Notifiables
What causes meningitis of weaner pigs? Trigger factors? Treatment? Prevention?
Most commonly Strep suis type 2
Trigger factors around 2-4w weeks post weaning - humidity, stress, mixing, moving
Antibiotics - penicillins, florfenicol
Anti-inflammatories and water per rectum
Bedding, darkness, warmth, quiet
Prevention difficult - reduce triggers, metaphylaxis with vaccination
Also linked with Haemophilus parasuis (Glassers) - multiple strains, clinically looks same as strep suit, difficult to culture, same treatment
What causes oedema disease of weaner pigs? What does it cause? When seen?
Shiga-like toxin producing strains of E.coli: action on blood vessels and endothelial cells (STEC)
Causes oedema of the brain, omentum, gastric mucosa and peritoneum, cardio-pulmonary system
High mortality with rapid onset
Usually within a month of weaning
Clinical signs of Oedema disease of weaner pigs?
Sudden death
Convulsions
Stupor
Ataxia
Anorexia
Pyrexia
Oedema of face and eyelids (puffy appearance)
High pitched squealing (laryngeal oedema)
Oedema very obvious within the spiral colon mesentery on PM
Diagnosis and treatment for Oedema disease of weaner pigs?
Diagnosis:
- culture
- serotyping and ID of toxins/fimbrial type
Treatment:
- improve management and hygiene
- toxins can make it difficult to treat
- anti-inflammatories
- water soluble antibiotics (in feed?)
- often at changeover of feed so nutrition has a role
- vaccination option from 4do appears relatively effective, can also vaccinate sows to transfer protection via colostrum
Clinical signs of water deprivation/salt poisoning?
Usually in grower/finisher stage
Sudden onset of nervous disease in multiple pigs Odd behaviour around water points Collapse Rolling Convulsions
Treatment for water deprivation/salt poisoning of weaner pigs?
Severe dehydration increases salt content in CSF
Rapid rehydration gives swelling of brain by osmosis
Steroids can help
Slow rehydration imperative
IV drips if warranted
Mortality can be very high
What can middle ear disease resemble? Clinical signs? What is it associated with? Treatment?
Clinically indistinguishable from early meningitis
Usually inner ear is affected, giving head tilt and head shaking
Often associated with Swine Influenza or PRRS
Can progress to meningitis
Treat with antibiotics and anti-inflammatories
When does MDA decline for PCV2, PRRS, M hyopneumoniae, Haemophilus parasuis, Actinobacillus pleuropneumoniae, Swine influenza?
Haemophilus parasuis: 4 weeks Swine influenza: 5 weeks PRRS: 6 weeks PCV2: 7 weeks M hyopneumonia: 12 weeks Actinobacillus pleuropneumoniae: 12 weeks
Clinical signs of PRDC in weaner and finisher pigs? PM?
Coughing Sneezing Pyrexia Conjunctivitis Dyspnoea Cyanosis Decreased appetite Loss of condition Mortality PM - pleurisy, pericarditis, peritonitis, polyserositis
What are the current main strains of Swine Influenza?
H1N1, H1N2 and H3N2
Clinical signs of Swine influenza? Incubation period? Immunity?
Piglets:
- unusual to see signs when sucking unless first introduction of disease into herd
- coughing
- pneumonia
- fever
Sows:
- pyrexia causing abortion
- widespread coughing
- pneumonia
- inappetence
- may start as 2-3 animals for 2 days, then rapid explosive outbreak
- acute respiratory distress persists for 7-10d
Incubation period = 12-48h with rapid dramatic onset
Immunity often short lived (6 months)
Herds may become endemic with intermittent bouts of disease and infertility
Epizootic form of Swine Influenza?
Multiple ages affected
Sudden onset
Triggers other diseases
Can persist in the herd - adds to PRDC
Treatment and control of Swine Influenza?
Supportive can reduce impact
NSAIFs
Antibiotics only if secondary bacterial disease risk
Control can be via vaccine use and biosecurity
Often becomes chronic disease
What causes Progressive Atrophic Rhinitis? Clinical signs?
Initial rhinos, sneezing -> destruction of turbinates
Pasteurella multocida type D toxin producing strain
Increases secondary infections, leading to decreased growth
Rare in UK commercially
Effective vaccine licensed
What causes Post weaning multi systemic wasting syndrome (PMWS)?
Porcine Circovirus type 2
Clinical signs of PMWS? Pathogenesis? Diagnosis?Treatment and Control?
Signs:
- Huge mortality through rapid loss of condition around 2-4mo
- Chronic wasting, diarrhoea, enteritis, occasional skin lesions
- Secondary infections
Pathogenesis: Lymphocytic depletion -> immunosuppression
Diagnosis:
- Clinical signs
- PCR
Treatment and control:
- Vaccination very effective and 95% of UK herd vaccinated so not really seen anymore
- No specific treatments
Overall respiratory control of weaner pigs?
Stop cycling of disease between groups - age, batches, pig flow, AIHO, hygiene
Reduce stress - stocking, water, feed, temperature
Diagnose and control specific infections - vaccination, medication
Eliminate certain pathogens
What causes Greasy Pig? Pathogenesis? Age affected? Transmission? Signs? Treatment? Control?
= Exudative epidermitis
Aetiology: Staphylococcus hyicus (skin commensal)
Most common skin disease
Pathogenesis:
- Can be acute or chronic
- Produces toxins which are absorbed into the system and damage the liver and kidneys
- Lesions caused by exfoliative toxin -> loss of keratinocyte cell-cell adhesion in the superficial epidermis -> leave skin open to secondary infection
- Often initiated by injury from sharp objects, unclipped teeth, fighting, or from mange or humid environment or immunosuppression
Age:
- Common in piglets >5do but causes bigger problem in weaned pigs
Transmission:
- multiplies profusely in sow’s vagina so piglets infected during birth process or soon after
Clinical signs:
- Typically non pruritic
- Loss of fluid can be fatal
Treatment:
- Amoxycillin or lincomycin
- Topical skin sanitiser in mild cases (e.g. Savlon)
Control:
- Hygiene
- Minimise fighting
- Humidity
What causes ear tip necrosis? What does it look like? Treatment?
Staphylococcal infection
Usually bilateral and dry
Around 7-12 weeks of age
Tends to heal on its own
What is the most common skin parasite of pigs? Species? Clinical signs? Diagnosis? Which animals are a particular problem? Treatment?
Sarcoptic mange: Sarcoptes scabiei var suis
Uncommon in commercial pigs
Signs:
- Intense pruritus
- crusty lesions
- lameness
- lethargy
- slowed growth
Diagnosis: deep skin scrapings
Boars can be a problem, - difficult to treat due to deep lesions, transfer to sows at service
Treat with ivermectin and bathe to stop secondary infections
Ringworm in pigs: Which species? Transmission? Signs? Treatment?
Commonly caused by Trichophyton mentagrophyes - involves contact with rodents
Contact with cattle can lead to Trichophyton verrucosum
Contact with cats can cause Microsporum canis
Signs:
- dirty marks on skin
- minimal pruritus
- usually affects groups
Treatment:
- clears with UV light
- other treatments not greatly effective
- generally resolves in about 2 weeks
Pityriasis rosea in pigs: Cause? When seen? Treatment?
= False ringworm
Genetic defect - inherited codnition
Sporadic dramatic appearance at 6-8 weeks old of individual animal
Non pruritic spreading rings - no other signs
Spontaneously resolves by 20 weeks old
Aims of the finishing period?
Maximise growth
Maximise efficiency
Huge balancing process based on: genetics, feed, housing, health
What is assessed in finishing pigs?
Carcass weight Grading Condemnation Growth rates Feed consumption
What determines whether a pig is fit to travel?
Must be able to load and unload itself Must be able to support their weight on all 4 legs Must have no open wounds Piglets can't be < 3 weeks Sows can't be < 1 week farrowed Sows can't be > 100d in pig 'Ambulance' conditions
What PHS Abattoir monitoring parameters are assessed?
EP-like lesions Pleurisy Pericarditis Peritonitis Papular dermatitis Pleuropneumonia-like Milk Spot Hepatic scarring Tail damage Viral-type pneumonia Abscess Pyaemia
When is PRDC seen?
Often starts in weaner period
But can be finishing only
Production impact of PRDC in finishers?
Decreased intake Reduced growth Loss of condition Low level mortality (3-15% post weaning if acute) Increased FCR (by 0.1-0.5) Increased DTB (by 7-30)
What makes up PRDC?
Viral: - PRRS - PCV2 - Swine influenza - Pseudorabies - Porcine respiratory Coronavirus Bacterial: - Glasser's disease - APP - Mycoplasma hyopneumoniae - Pasteurella multocida - Bordetella bronchiseptica - Streptococcus suis Management and environment: - Overcrowding - Ventilation - Temperature - Mixing different sources - Continuous flow - Sanitation
Total mortality and culls % due to PRDC? Total £ cost?
4-8%
£12,000-25,000
Enzootic pneumonia: Aetiology? Incubation period? Significance? Pathology? Spread? Diagnosis?
Mycoplasma hyopneumoniae Endemic in most herds 6-8 weeks incubation Unimportant in well housed and managed pigs, but can have serious effects if concurrent infections with APP, Has, Pasteurella, PRRS or SI Pathogenesis: - Slow action of pathology - Interstitial pneumonia and bronchiolar cuffing - Mucocilliary escalator damage - Often secondary infection - Decreased growth due to immune challenge and healing Transmission: - Carrier pigs - Wind borne spread up to 5 miles - Dies quickly outside pig (but can live for 2-3d in moist, cool conditions) Diagnosis: - clinical picture - PM: lungs - ELISA - PCR
What pathology of enzootic pneumonia can be found at PM and slaughter?
Dependent lobes end up consolidated with pneumonia - apical, cardiac, cranial region of diaphragmatic and accessory lobes
Dependent on secondary infection, overlying pleurisy can be present
Diagnosis of enzootic pneumonia in pigs?
EP-like lesions grossly
Histopathology
PCR
Control and treatment of Enzootic pneumonia in pigs?
Interruption of disease cycle is best to reduce infection pressure
Antibiotics - individual, water and via feed
Tetracyclines, maacrolides, pleuromutilins
Vaccination important as long term control - cost effective, can eliminate the disease
Full depop-repop
Partial medicated depot - move most susceptible animals off site, vaccinate, hygiene, medicate
How do EP lesions affect % loss of DLWG?
Up to score 10: 0%
Score 41-55 (max): 50%
What is the primary target of PRRS?
Alveolar macrophages (multiplies in immune system)
What problems does Actinobacillus pleuropneumoniae (APP) have?
Persistent once in herd
Can give acute/peracute outbreaks, especially when following PRRS or influenza
Can also be chronic on its own
Clinical signs of acute APP in pigs?
Big pigs suddenly dead - very little pathology
Background cough
Pyrexia and lethargy
Bloody nares (often only seen once dead)
What pathology is seen with APP in pigs?
Hugely variable
Peracute - none
Acute - haemorrhage lesions
Chronic - solidified pneumonia with overlying pleurisy
Treatment and control of APP in pigs?
Treatment is often too late in outbreaks
Injectable, water or via feed penicillins, florfenicol, TMPS
Commercial vaccination against APX toxins
Autogenous vaccine?
Partial medicated depot to eliminate
What must be ruled out when suspicious of acute APP outbreak with sudden death?
CSF/ASF Salt poisoning Toxicities Acute Glassers Endocarditis
What causes swine dysentery? Pathogenesis? Blood parameters? Transmission/risk factors?
Brachyspira hyodysenteriae
Pathogenesis and signs:
- causes ulcerative colitis/typhylocolitis (severe inflammation of LI)
- invades intestinal epithelium particularly of caecum and colon
- produces toxins
- goblet cell hyperplasia
- malabsorptive diarrhoea very common, often contains blood and mucus (mucohaemorrhagic scour)
- risk of secondary infection
Blood parameters:
- Increased IL-1 and TNF-a common
Transmission/risk factors:
- infection via ingestion of infected faeces
- spread by carrier pigs that shed in faeces for long period of time
- faecal contamination of equipment, boots etc
- can be spread by flies, mice, birds, dogs etc
- stress from change of feed may precipitate
- poor sanitation and wet pens
- overcrowding
Differentials to signs caused by swine dysentery?
Porcine Haemorrhagic Enteritis (ileitis) Severe colitis Gastric/intestinal ulceration Trichuris suis CSF/ASF
Diagnosis, treatment and control of swine dysentery?
Diagnosis: - clinical picture - blood and mucus faeces sent off for PCR or culture - fluorescent Ab tests on faecal smears - gram stained faecal smears rules out other organisms - PME Control: - Pleuromutilins - Lincomycin or tiamulin (not tyrosine as resistant): in water for at least 7d at first signs of disease, inject badly affected pigs daily for 4 days - Hygiene important - Prevent access to slurry pits - Control flies - Footbaths for farm people - Reduce movement and handling of pigs - Avoid overcrowding - Isolate and quarantine incoming pigs - Often move towards elimination - based on diagnostics including MICs - Partial medicated depot - Combo medication, hygiene, planning - Not viable to control long term - No viable vaccine options currently - Autogenous vaccine?
What does Brachyspira pilosicoli cause in pigs? Clinical signs? Control?
Spirochaetal colitis
Mild - common commensal
Often mixed infection with Lawsonia and Salmonella
Appearance of grey cow pat mostly - rarely has some blood present
Usually control through nutritional changes
What does Lawsonia intracellularis cause? Diagnosis, treatment and control?
Porcine Intestinal Adenopathy (PIA)
Porcine Haemorrhagic Enteropathy (PHE)?
Diagnosis: - Clinical signs - Can only be differentiated from colitis by PCR +/- culture - Histopathology Treatment and control: - Range of antibiotics e.g. macrolides - Live attenuated vaccine
What does Porcine Intestinal Adenopathy (PIA) cause? Pathogenesis? Diagnosis? Treatment? Which pigs affected?
Low grade infection of Lawsonia
Thickened distal ileum with proliferative lesions of enterocytes (hose pipe like appearance) - can extend into proximal colon
Pathogenesis:
- Infection of enterocytes causes proliferation/hyperplasia of crypt cells
- Causes malabsorption of intestinal contents
- Involves bacterial T3SS and T5SS and host inflammatory response
-> low grade ‘food coloured’ scour
-> poor growth - stunted pigs
Can be acute (bloody diarrhoea, sudden death) or chronic or subclinical
Mostly finisher pigs
What does Porcine Haemorrhagic Enteropathy (PHE) cause? PM? Which animals affected?
Acute Higher grade infection than PIA
Can be difficult to distinguish from swine dysentery
But usually no diarrhoea?
Acute haemorrhage, rotten blood smell, sudden death
Usually more mature animals nearer bacon weight
PM: thinning of ideal walls with haemorrhage leading to blood filled intestinal lumen
What is nutritional scour in finisher pigs? Cause? Control?
Low grade colitis, often with disruption to microbiome
Change of feed too abruptly - feed rations, raw materials (barley, wheat)
Gorging suddenly
Control through correcting nutritional insult and hygiene
Can Ascaris suum cause a problem in finisher pigs?
Not usually a problem clinically
Can cause some respiratory issues as part of PRDC - migrating L3
Milk spot picked up at slaughter - migrating L2
Decreased growth rates
Treatment for Ascaris suum?
If causing issue, worm individually or as group
BZs and avermectins
Eggs viable for 7y+ on paddocks
Hygiene to remove eggs - washing soda, clean down
What does Trichuris suis (whipworm) cause in finisher pigs? Control?
Clinically similar to swine dysentery
Irritative colitis - unresponsive to antibiotics
Worming needs to be repeated at high doses
Hygiene v important - washing and lime wash
Clinical signs/PM of gastric ulceration in pigs? Triggers?
Common in fast growing pigs
Melaena, sudden death, pale carcass, clotted blood in GIT, ulcers can be found
Pars oesophageal affected
Complex triggers - stress, grist size, high protein, high wheat
What is gastro-intestinal volvulus? Result? Aetiology? PM?
Half or full rotation around base of mesentery
Very quick progression to death
Complex aetiology - fresh grains, fermentation, high protein diets
Swollen carcass, pale, classic positioning of GIT on PM
Causes of rectal prolapse/stricture in pigs? Clinical signs of stricture? Treatment?
Linked to scour and increased abdominal pressure (coughing, huddling)
Replace if fresh - gloves, pressure, purse string suture
Amputate if old - surgical, pipe and rubber band
Secondary stricture highly likely, leading to GIT blockage - swollen abdomen, loss of condition, jaundice, can feel on digital palpation - ease open if possible, if not euthansia only option
Clinical presentation of Erysipelas?
Peracute - found dead - septicaemia carcass
Acute - highly pyrexic, lethargy, raised skin lesions (typically diamonds but not always)
Chronic - endocarditis, very stiff lameness
Spread and control of Erysipelas in pigs?
Often environmental and carried by wildlife - more common in outdoor herds and small holdings
Commercial breeding herds are usually vaccinated - can cause abortions in gilts and sows
Treatment and control for Erysipelas in pigs?
Penicillin very effective
Can use water medication when flare occurring but long term control should be vaccination
Must vaccinate growing pigs after MDA has decayed (so after 6 weeks post weaning)
Control infection source - esp birds and rodents
Clinical signs of Mycoplasma hyosynoviae in pigs?
Off legs, difficulty rising, lameness
Early cases can apparently ‘walk it off’
Swelling can be minimal - often hips and stifles affected
Treatment and control for Mycoplasma hyosynoviae in pigs?
Speedy response to lincomycin/tiamulin - need to complete the course
No vaccine available
Autogenous vaccine?
Causes of biting in pigs?
Frustration Stress 'Overstocking' Draughts Discontent Understocking Nutritional upset Disease
Outcomes of biting in pigs?
Huge welfare issue
Local or tracking abscessation
Death/euthanasia
What are the legal requirements for registering/moving commercial or pet pigs?
Site must be registered with DEFRA - CPHH number
All movements need to be registered - eAML2 (electric database), includes wandering ‘stud’ boar, movement standstill period, 20d for pigs, 6d for ruminants
Walking licenses - specific route detailed by DBM, requires collar and lead
What rectal temperature is usually taken to be the top of normal for pigs?
39.5C
But can be above this is stressed etc
How much energy, protein and % of BW should a pet pig get?
Around 13MJ
15-16% protein
Around 1% of BW daily
Problems with obesity in pet pigs?
Arthritis Inactivity Joint issues Foot problems Dermatitis Eye issues
Causes of emaciation in pet pigs?
Not eating due to pyrexia, too hot, rubbish food, no water
Heavy parasite burden
Wrong food
Zoonotic considerations in pigs?
Ascariasis Brucellosis Campylobacteriosis Cysticercosis Erysipelas Hepatitis E Leptospirosis Ringworm Salmonellosis Streptococcus suis type 2 Swine influenza Tetanus Toxoplasmosis Trichinellosis
Most common reproductive issue in pet pigs and its cause?
Anoestrus due to obesity
Which breeds are more prone to scrotal hernias?
Vietnamese Pot Bellied
Kune-Kunes
What enteric diseases are seen in pet pigs?
Scour less common as infection burden low
Nutritional more common due to unusual diets
Twisted guts can result from abrupt changes to food and water
Ulcers from low level stress can be common - intermittent feeding and large numbers of stones will not help
Main cause of respiratory disease in pet pigs?
Ascarid worm burdens affecting lung function from migrating L3
Skin diseases seen in pet pigs?
Mange - very common
Lice (Haematopinus suis) - uncommon
Ringworm - variable
Erysipelas - same as commercial pigs
Insect bites
Greasy pig most common bacterial infection in skin folds
Sunburn when insufficient mud/dust to cover in
Zinc and vitamin B deficiencies causing parakeratosis
Photosensitisation - can be indication of toxins e.g. parsley, ragwort
Contact allergies - urine scald
Old age alopecia
Wounds
Causes of lameness in pet pigs?
Joint issues - often obesity/age related, treat with anti-inflammatories and bedding
Overgrown claws - need solid ground to walk on, trim
Mild fractures - from nutritional deficiencies (calcium, phosphorous, vitamin D, biotin)
Infections - staph/strep, treat with penicillin and anti-inflammatories
Erysipelas - common cause of stiffness that does not ‘walk off’
Where to perform IM injections of pigs? What needle to use?
Neck muscle
1.5in 16G for adult pigs
1in 18G for smaller pigs
1in 21G for piglets
Which NSAIDs are good for analgesia of ‘old age’ issues in pet pigs?
Ketoprofen - oral and injectable
Meloxicam - oral and injectable
Tolfenamic acid - injectable
Phenylbutazone - not licensed, must not enter human food chain
Basic routine treatments to carry out for pet pigs?
Erysipelas vaccination - twice a year
Clostridial vaccination - twice a year
Parasite control - Ivermectin twice a year
Iron injection for piglets (depends on soil access)
How to de-tusk a boar?
Sedate heavily - beware priapism
Use embryotomy wire
Saw at diagonal as close to gum as possible
No nerves in tooth itself and only blood is if gum caught
Wire will get hot enough to burn - care
Remove all at same time
How to castrate a boar?
In controlled environment at surgery not field if poss
Sedate
- Aseperone licensed IM (beware priapism)
- Xylazine/butorphanol off licence
Anaesthetic
- Ketamine IV or IM
- Pentobarbital not licensed or sterile, not to enter food chain
- Inhalational
Difficult to assess before induction (e.g. auscultation) - increased risk of anaesthetic death
Plane of anaesthesia difficult to maintain due to fat distribution - will wake up quickly and walk off
Surgical procedure similar to dog castration, slightly further caudal on edge of scrotum
Tying off cord is personal preference - no need to suture skin incision if kept clean
Analgesia - NSAIDs
Antibiotics
Poss risk of tetanus
Scrotal hernias commonly discovered - correct while under GA
Euthanasia options for pet pigs?
Gun (free bullet or captive bolt) - method of choice, beware rebound, good restraint required for captive bolt
Barbiturate injection - usually owner preference, venipuncture not easy, can do intracardiac in small pigs, may need to sedate first with azeperone, ear veins easy to blow
Reasons for a disease being made notifiable?
International trade and animal/human welfare - devastating infectious disease, high mortality/morbidity, debility if survive, confusion of diagnosis
Public health - zoonotic implications
What pig notifiable diseases are there?
FMD SVD Vesicular stomatitis Vesicular exanthema Seneca Valley A Virus Classical Swine Fever African Swine Fever Teschen Disease PED high path Aujeszky's Disease Brucella suis Anthrax Rabies
What type of virus causes FMD? What serotypes are there? What species are affected?
A Picorna virus
7 serotypes: O, A, C, SAT1, SAT2, SAT3, Asia-1
Affects cloven hoofed livestock (cattle, sheep, goats, pigs) and wildlife (buffalo)
Why is FMD a problem to control?
Highly contagious - rapid replication and short incubation, massive virus release, high susceptibility of hosts, several transmission routes
What is the incubation period for FMD and what does it depend on?
2-14 days
Dose of virus which animal has been exposed to (longer incubation if low dose, shorter if high dose)
Virus strain
Route of infection
How is FMD transmitted?
FMDV present in the fluid inside blisters, saliva, urine, dung, milk, exhaled air
Also present in blood at the height of the disease
Direct contact between infected and susceptible animals or from contaminated objects
Indirect via:
- Consumption of untreated contaminated meat products (swill feeding of pigs)
- AI with contaminated semen
- Inhalation of infectious aerosols
- Airborne
How long can humans harbour FMDV in their respiratory tract? Quarantine?
24-48h
3-5d personal quarantine to those exposed in research facilities
General clinical signs of FMD in pigs?
Pyrexia
Sudden lameness - tendency to lie down and unwilling to move
Formation of vesicles mostly on feet - upper edge of the hoof where the skin and horn meet
Area above coronary band swollen, coronary band full of fluid
Hot feet
Vesicles on snout or tongue
Large number of herd affected
Reluctance to feed
Abortion or sudden death in piglets
Differential diagnoses for clinical signs suggesting FMD in pigs? How to differentiate?
Other vesicular diseases: - Swine vesicular disease (SVD) - Vesicular exanthema (VE) - Vesicular stomatitis (VS) - Seneca Valley A virus Differentiate with lab test Chemical agents and trauma (cuts/bruising) - differentiated by the absence of vesicular lesions and high fever
What type of virus causes Swine vesicular disease (SVD)? Clinical signs?
Enterovirus
Vesicles on feet mostly
Occasionally vesicles on snout and other sites
What type of virus causes Vesicular exanthema (VE)? Clinical signs?
Calicivirus
Vesicles on snout, oral mucosa and feet
Occasionally diarrhoea, abortions and agalactiae
What type of virus causes Vesicular Stomatitis (VS)? Clinical signs?
Rhabdovirus
Vesicles on feet, mouth, nostrils, snout and teats
Humans are susceptible and can suffer an influenza like disease
What type of virus causes Seneca Valley A virus? Clinical signs?
Pircornaviridae family
Vesicles
What is African Swine Fever? Which species infected? Type of virus caused by?
Viral haemorrhage disease of suids
Also infects Ornithodirus ticks in the wild
Caused by a large, cytoplasmic dsDNA virus
Only member of Asfarviridae family
Transmission of ASF?
Direct
Indirect (feed, fomites)
Ornithodirus ticks
Clinical signs of virulent strains of ASF in pigs?
Peracute form - sudden death with few signs Acute form: Death within a few days (mortality can reach 100%) Pyrexia (>41C) Anorexia, apathy, incoordination Vomiting and diarrhoea (may be bloody) Respiratory signs Conjuncitvitis Cyanosis of extremities Abortion No age dependency
Incubation period of ASF?
3-19d
Clinical signs of less virulent ASF strains in pigs?
Subacute and chronic forms Varied signs, often not specific Weight loss Reduced growth Lameness Respiratory signs Abortion Mortality rates depend on strain
What type of virus causes CSF?
Pestivirus (closely related to BVD and BDV)
Haemorrhagic disease
What do CSF clinical signs depend on?
Vary depending on isolate, age of pig and herd immune status
Transmission of CSF?
Oral/oronasal route Mucous membranes Skin abrasions Aerosols Fomites Carrier animals
Clinical signs of highly virulent isolates of CSF in pigs?
Pyrexia Weakness Anorexia Conjunctivitis Constipation followed by watery diarrhoea Vomiting Incoordination or unsteady gait Skin haemorrhages or cyanotic discolouration Death within 1-3 weeks Severe leukopenia
Clinical signs of moderately virulent isolates of CSF in pigs?
Similar to highly virulent but signs less severe
Course is prolonged and lower mortality rate
Clinical signs of low virulent isolates or partially immune herds of CSF in pigs?
Chronic disease
Varied signs
Can resemble highly or moderately virulent strains with pigs then improving, followed by signs returning
Can see wasting, reduced growth, skin lesions, immunosuprpession
Breeding herds - may only see poor reproductive function
Differential diagnoses for CSF signs?
Other haemorrhage diseases of swine - ASF/CSF - lab test
Septicaemia - Salmonella, Erysipelas, Pasteurellosis, Haemophilus
Other causes of abortion - Aujeszky’s, PRRS< Parvovirus
Runting - PMWS, Campylobacter, Swine dysentery
what are the 2 types of PED?
PED type 1 - growing pigs
PED type 2 - all ages
What type of virus causes Teschen disease? What is it? Clinical signs?
Enterovirus (Teschovirus)
Causes polioencephalomyelitis
Talfan is mild form occasionally reported in UK
High fever, incoordination, inappetence, tremors, convulsions, death
All ages can be affected
What type of virus causes Aujeszky’s disease (pseudorabies/mad itch) in pigs? Spread?
Herpes virus - persistent infection
Windborne
Clinical signs of Aujeszky’s disease (pseudorabies/mad itch) in adult pigs?
Abortion storms Mummification Mild pyrexia Anorexia Vomiting
Clinical signs of Aujeszky’s disease (pseudorabies/mad itch) in piglets aged 3d - weaning?
V+D progressing to nervous signs with pyrexia Incoordination Dog sitting muscle tremors Opisthotonus Convulsions Mortality reduces with age
Clinical signs of Aujeszky’s disease (pseudorabies/mad itch) in weevers and growers?
Pyrexia
Incoordination progressing to dog sitting, convulsions and death
Pneumonia
What non routine mutilations of pigs are there?
Teeth reduction
Tail docking
Ear notching
Castration
What are the methods of teeth reduction? What is the aim?
Clipping (risk of shattering) or grinding
Aim to just remove the points of the 8 deciduous teeth so cannot break skin and cause damage to each other and udders
What is the aim of tail docking?
Amputate to point where nerves are present so can feel sensation and will react if another piglet starts biting it, to reduce incidence
(no nerves at end of tail)
What are the laws for castration? Why not really done in UK?
Anaesthesia needed if > 7do
Must be vet if > 7do
Not allowed by Red Tractor
What are the five freedoms?
Hunger and thirst Discomfort Pain, injury and disease Fear and distress To express normal behaviour
Signs of good health in pigs?
Bright Responsive Eating/drinking well Quiet, settled breathing Normal colour/consistency of muck Normal urine Good skin and colour 'Barking' Normal temperature
Who can provide training for euthanasia of pigs?
A vet
BPEX - emergency killing workshop
Humane slaughter association On-Farm Killing of Red Meat Animals - Theory and Practice
Suitably trained and experienced person as signed off by vet
What records are required for training and assessment of competency for euthanasia of pigs (Red Tractor)?
Recorded and signed by Vet in VHP Or Declaration (by vet) of training on PIPR Or Recorded in farm training records (and signed by vet when assessed)
What are the Red Tractor requirements (2017) for euthanasia of pigs?
A named person must be responsible for euthanasia of stock on every RT site
A competent and trained person should be available to attend the site within 60 mins 24/7/365
Only persons who have been formally trained, and assessed as competent may carry out euthanasia, from April 2014
Competence must be assessed as soon as possible after training
Competence must be re-evaluated by the person responsible for euthanasia every 3 years
What are the legal requirements of euthanasia of animals?
Killing must result in unconsciousness immediately and remain so until death
All methods of stunning are followed by bleeding or pithing
Animals must be restrained in an appropriate manner so as to avoid pain, suffering agitation, injury or contusion
Method chosen must not endanger human life
What is emergency killing?
In an emergency, a pig can be killed by any means that is effective and kills humanely without causing avoidable suffering
What methods of stun can be used in pigs?
Electronarcosis
Captive bolt
Carbon dioxide
Methods of killing pigs?
Shotgun Rifle Captive bolt followed by bleeding/pithing Free bullet humane killer Lethal injection External trauma
What conditions require emergency killing of pigs?
Injury
Conditions/diseases unlikely to respond/not responding to treatment
Runts - at time they are recognised to be potentially suffering
Herniated pigs - at time they are recognised to be potentially suffering
What is death?
Irreversible loss of all functions in the brainstem responsible for the control of respiration and circulation
Loss of heart beat or breathing eventually leads to brain death from lack of oxygen
Brain death leads to lack of spontaneous breathing which results in lack of oxygen to the heart and cardiac arrest
What licence is needed for emergency killing of pigs with captive bolt? What must be done?
No licence required for emergencies
Does not kill - must follow with another method to kill pig
Must be restrained well - static health
How does a captive bolt work?
Rapid acceleration of skull
Lag of brain
Brain strikes skull
Sudden increase in intra-cranial pressure
Disruption in normal electrical activity
Damage to nerves and blood vessels from shearing forces, and actual bolt itself
Length of time of unconsciousness depends on severity of damage
What does the effectiveness of the captive bolt depend on?
Correct positioning - site and angle
Speed of bolt force - size of cartridge, correct maintenance of equipment
A static head
Signs of an effective captive bolt stun?
Pig collapses immediately
- tonic stage - stops breathing, becomes rigid with head raised, forelegs extended and hindlimb flexed
- eyes fixed and immobile, staring with no blink reflex
Pig moves into clonic phase - unconscious but muscles start to relax, then involuntary kicking occurs for 1-2 mins
Watch out for recovery within 30-60 seconds
Becomes ineffective as clonic activity fades and rhythmic breathing restarts, blink reflex returns and pain can be felt
How to pith after captive bolt to kill? How does it work?
Vigorous to-and-fro movements with pithing rod
Causes lack of oxygen to brain stem by blood loss from bleeding out
How to check for death?
Fixed eye, no blink
No signs of breathing
Heart has stopped
Shotgun for killing of pigs?
Requires a licence or can be used under supervision
Use same point as for captive bolt or use ear base to opposite eye
Methods of killing piglets?
Blunt trauma if under 5kg - hit with blunt object or against one
Turkey stunner - needs proper restraint
Barbiturate overdose - intracardiac/intraperitoneal
Gassing (CO2)
Where to take blood samples from pigs?
Jugular or cranial vena cava - must restrain correctly e.g. with snitch
Tail vein - not easy but small sample volumes
Ear vein - very friable and collapse easily, very sensitive
What GI bacterial infections fo pigs mainly get?
Lawsonia intracellularis Brachyspira E. coli Clostridia Salmonella enterica Campylobacter
Features of Lawsonia intracellularis?
Obligate intracellular gram negative curved rod
Causes of porcine skin lesions?
Physical (objects), lying on rough surfaces
Vices (biting)
Vector driven (flies and lice)
Infection (Bacterial, parasitic, viral, fungal)
Congenital (epitheliogenesis imperfecta)
Toxic (PDNS, porcine dermatitis and nephropathy syndrome)
Problems with porcine skin lesions?
Can lead to:
- carcass condemnation
- septicaemia
- spinal lesions (from tail bites)
- culling
- death
- welfare issue - checked for farm assurance
Infectious causes of skin lesions in pigs?
Septicaemia Greasy pig Swine pox Ringworm Treponema Sarcoptic mange
What can cause skin discolouration due to septicaemia in pigs?
Salmonellosis Glasser's disease PRRS Swine fever Erysipelas
Glasser’s disease: Aetiology? Pathogenesis? Transmission?
Haemophilus parasuis
Attacks the smooth surfaces of the joints, coverings of the intestine, lungs, heart and brain
Causes pneumonia, pericarditis, peritonitis, pleurisy
Respiratory spread
Swine pox: How common? Transmission? Significance? Diagnosis?
Rare
Can be congenital
Limited significance unless associated with secondary greasy pig disease
Confirmed by virus isolation but unrewarding
Porcine dermatitis and nephropathy syndrome (PDNS) in pigs: Which groups affected? Mortality rate? Signs? Cause?
Mainly in growers and finishers
Mortality around 15%
Signs:
- extensive greasy brown, purplish red slightly raised blotches of various sizes and shapes over the chest, abdomen, thighs and forelegs
- majority of pigs that develop extensive skin blotching die
- depressed, loss of appetite, fever, immobile/reluctant to move
Can affect kidneys
Cause: possibly Porcine circovirus 2 (PCV2)
Treponeme infections in pigs: When seen? Problems?
Likely secondary invaders of previous lesions
Likely to prevent wound healing
Mouths can also be positive
Same species as in cows, sheep, goats, horses - risk of transmission
Treatment and control currently unknown but likely similar to cattle
Not associated with foot lesions in pigs
What physical damage and other non infectious skin lesions do pigs mainly get? Which animals? Treatment?
Shoulder sores: associated with weight loss during lactation, from rough surfaces
Lower limb abrasions
Stifle sores: mainly in fast growing finishers kept at high density with no bedding
Teat necrosis in piglets: can affect future breeding potential, can stick tissue paper over from 6 teats at birth
Treatment: remove from offending area, provide soft, comfortable bedding
Other:
- 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
Biting in pigs: Which animals? Why? Where? Prevention?
Who:
- Testosterone driven males are notorious biters, but females do too
- Tail biting common in finishers (3 times more common in undocked pigs)
- vulva biting of sows in late pregnancy: may affect farrowing and mating and can cause prolapse and (rarely) lead to death
Why: Competition for space, food, resources etc (particularly with intensive farming)
Where: Flanks, ears, tails and vulva common biting sites
Prevention:
- Straw bedding
- Toys (balls, CD’s 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’
Epitheliogenesis imperfecta in pigs: What is it? Cause? Treatment?
Absence of epidermis or mucosal epithelium
Congenital
Commonly on legs or flanks
Will heal slowly but may require sutures in severe cases
Cull if very severe
Swine dysentery: Which pigs affected? Incubation period? Immunity? Costs? Survival of bacteria?
Common in pigs 12-75kg but severe cases can occur in sows and their sucking piglets
Incubation period = 7-14 days (can be up to 60 days)
May develop a sub-clinical carrier state initially, then break down with clinical disease when under stress or change of feed (so can carry and shed bacteria without clinical signs)
Recovered pigs develop a low immunity and rarely suffer the disease again
High cost of disease associated with:
- mortality (low)
- morbidity (high)
- depression of growth and feed conversion efficiency
- costs of continual in-feed medication
Bacteria will survive outside the pig for up to 7 weeks in cold moist conditions but it dies out in 2 days in dry warm environment
Difficult to eradicate from a herd
Clinical signs of swine dysentery in piglets and weaner/growers?
Piglets:
- severe acute dysentery
- sloppy light brown faeces +/- mucous/blood
- loss of condition
Weaner and growers:
- sloppy diarrhoea which stains the skin under the anus
- initially light brown diarrhoea with jelly like mucus, then becomes watery and may contain blood
- twitching of tail
- hollowing of flanks with poor growth and loss of condition (loss of condition can occur rapidly over 2-3 days)
- partial loss of appetite
- slight reddening of the skin
- dehydrated
- gaunt appearance with sunken eyes
- sudden death sometimes occurs, mainly in heavy finishers (with aggressive strains)
What can E.coli cause in pigs?
Neonatal scour
Post weaning diarrhoea (ETEC)
Oedema disease
What is the main cause of disease by C perfringens in pigs?
Toxins
What does Clostridium novyi cause in pigs? What happens?
May cause systemic infection in sows. especially outdoor-reared as likely source in soil
Migration of bacteria from gut to
liver
Toxins produced in liver causing necrotic or gangrene-like lesions
May result in distinct ‘Aero
Chocolate’ liver
Treatment and control of Clostridial diseases in pigs?
Difficult as ubiquitous
Mostly diagnosed at PM - gram staining of mucosal lesions
Antibiotic therapy may be useful for C dificile and type A perfringens
Therapy too late for type C as effects are irreversible once symptoms present
Vaccines for perfringens and novyi but efficacy limited
Campylobacter in pigs: Which species? What does it cause? Risk to humans?
C. coli or C. mucosalis can lead to porcine enteritis
C. coli may also be carried without disease and a source of human campylobacteriosis
C. coli causes 10% of human cases in UK
What viral infections of the GIT are pigs affected by?
Rotavirus
Coronavirus and TGE virus
Porcine Circovirus
Porcine rotavirus: What does it cause? Which serogroups? Type of virus? Transmission? Pathogenesis?
Diarrhoea (species-specific strains)
dsRNA virus
Four serogroups infecting pigs (A,B, C, E)
Virus circulates in herds - 30% of sows excrete virus at farrowing and survives well in environment
Pathogenesis:
- Virus infects intestinal epithelial cells damaging
villus tips leading to enteritis and scour in piglets
- Can be a co-infection with E. coli
Diagnosis:
- ELISA, IFAT
Treatment and control:
- Non specific
- Dehydration is the main problem so hydration support
- Hygiene improvement
- Environmental control - reduce chilling
- Vaccination: Serogroup A for sows -> maternal Ab and colostrum protection
Porcine Circovirus: Types? Type of virus? What do they cause? Transmission?
Non enveloped DNA virus
PCV1 largely avirulent
PCV2 always associated with Postweaning Multisystemic Wasting Syndrome (PMWS) but not proven as causative agent
Reproductive failure: mummification, non viable piglets at parturition
Shed by boars at low amounts in semen for extended time periods
Vertical transmission to foetuses during viraemia of dam
Horizontal spread (inc intrauterine infected piglets that are clinically normal)
What biosecurity measures should pig farmers implement?
Prohibit unnecessary visitors
Cleanse and disinfect any shared equipment before it enters and after it leaves the premises
Make sure personnel in contact with pigs at other premises take standard precautions, such as cleaning and disinfecting boots and clothing
Prevent people with flu-like symptoms coming into contact with pigs
What is the window of susceptibility for disease?
The gap when passive (maternal) immunity declines, before adaptive innate and immunity have increased fully
PRRSV vaccines?
Live attenuated vaccines for type 2 PRRSV
Effective in reducing clinical signs and duration of shedding
Not likely to completely prevent infection
Safety problems - vaccine viruses persist in vaccinated pigs and can spread to unvaccinated pigs, reversion to virulent type possible
PRRS Porcillis vaccine protocol?
Single dose given to pigs from 2wo onwards
Finishing pigs: single vaccination is sufficient for protection until slaughter
Breeding pigs:
- for gilts a (re)vaccination 2-4 weeks before mating is recommended
- to maintain a high and homologous level of immunity, revaccination at regular intervals is recommended, either before each next gestation or at random at 4-month intervals
- Pregnant sows should only be vaccinated after previous exposure to European PRRS virus
Advised to vaccinate all target pigs within a herd from the earliest recommended age onwards
Maternally derived antibodies may interfere with the response to vaccination.
Newly introduced PRRS virus-naϊve animals (e.g., replacement gilts from PRRS virus-negative herds) should be vaccinated prior to pregnancy
Porcilis PRRS must only be used in PRRS virus contaminated herds, where prevalence of European PRRS virus has been established through reliable diagnostic virological methods
No data are available on the safety of the vaccine for the reproductive performance in boars
It should not be used in herds where a PRRS eradication program based on serology has been adopted
What factors contribute to seeing disease from swine influenza?
Infected animals, including people, pigs and birds Carrier pigs Poss wind Waterfowl = reservoir Secondary bacterial infections Fluctuating temperatures Stress Wet bedding and floor surfaces Poor nutrition
Environmental factors that increase the disease caused by enzootic pneumonia in pigs?
Overcrowding and group sizes of >200
Variable temperatures and poor insulation
Houses with poor hygiene and high levels of CO2 and ammonia
High dust/bacteria levels in air
Pig movement, stress and mixing
Shortage of trough space
Housing with continuous throughput of pigs
Other concurrent diseases
Poor nutrition
Slatted floors and liquid waste
Bordetella bronchiseptica in pigs: Pathogenesis? PM findings? Diagnosis? Signs? Control?
Pathogenesis:
- colonises ciliated epithelium of respiratory tract
- results in decreased mucociliary apparatus function and pneumonia
PM findings:
- typical gross lesions are a necrohemorrhagic pleuropneumonia in young pigs or a tan, firm bronchopneumonia in older pigs
- acute form in neonates grossly resembles APP with a cranioventral distribution
- more chronic form in nursery and grower pigs is very firm and tan with fibrosis
Diagnosis: isolation of organism from nasal swabs, trachea, or lung
Signs:
- some strains cause a mild, non progressive rhinitis that heals spontaneously = no consequences
- severe progressive rhinitis (atrophic rhinitis) if in combination with toxigenic Pasteurella
Control:
- Nasal vaccination = avirulent live culture for piglets, stimulates a secretory IgA response and blocks Bb receptor sites
Timings of the pig production cycle?
Service of sow 2-3 times
Farrows at 115 days
Weaning at 3-4 weeks
Sow commences heat at 6 months
Pigs for meat slaughtered at 20-24 weeks
What is the most important infectious agent causing reproduction failure in sows and severe pneumonia in piglets?
PRRSV (type 1 prevalent in Europe)
PRRSV: Type of virus? Where does it replicate?
Arterivirus
Replicates in the perinuclear cytoplasm of host cells (primarily alveolar macrophages)
Pathogenesis of PRRSV?
Transmission by inhalation, ingestion, coitus, skin damage and contaminated needles
- > Replication in mucosal, pulmonary, or regional macrophages
- > Regional lymph nodes and viraemia
- > Systematic distribution to mononuclear cells and tissue macrophages
- > Lysis of pulmonary alveolar macrophages and apoptosis of bystander cells
- > Clinical disease
Clinical signs of PRRS in sows, growers, finishers and boars?
Sow: - abortion/premature farrowing - still borns/mummified - weak live borns (50% die soon after birth) - delayed return to service - fever - lethargy - pneumonia - agalactiae - red/blue discolouration of ears and vulva - death in rare cases Growers and finishers (usually subclinical infection): - destruction of macrophages - thickening of alveolar septa - minor heart and vessel lesions - respiratory signs if clinical e.g. fever, sneezing, dyspnoea, coughing, pneumonia, oculonasal discharge Boar: - fever - semen changes
What type of pneumonia does PRRS cause?
Interstitial pneumonia
Interaction of PRRS and other pathogens?
Mycoplasma enhances the pathological effects of PRRSV
PRRSV enhances the pathological effects of Porcine Influenza virus
PRRSV predisposes pigs to infection and disease caused by Streptococcus suis
PRRSV can cause a loss of the bactericidal function of pulmonary intravascular macrophages
Diagnosis of PRRS?
Serology - ELISA
IF
PCR
African swine fever: Spread? Aetiology? What does it cause? Stability? Control?
Spread in feed, by aerosol, or by Ornithodorus (soft tick)
Asfivirus
Causes fatal haemorrhagic disease of pigs
Highly stable virus - survives well in meat
No vaccine
Treatment for pigs with raised skin lesions, pyrexia and depression?
3 days procaine penicillin
How to induce pigs to farrow?
Deep IM cloprostenol sodium (prostaglandin) only when accurate service records are kept
What to assume and do if sow been straining unsuccessfully for 1hr to pass first piglet. Exam: head of single piglet in anterior vagina which you can grasp easily
Foetal malpresentation in anterior presentation
Use traction to extract foetus
