Pig Health, Welfare and Behaviour AHW

dangers from working with pigs:

Lone working

Noise levels- Pig sheds can reach over 100 dB

Respiratory issues- From dust or infectious agents

Injury from the pigs- You know these from the pig handling session!

Zoonotic infection:

-Streptococcus suis (bacteria)

-Trichinella sp. (nematode parasite [roundworm])

-Influenza A virus (H1N1 pandemic strain in 2009)

how to prevent harm to yourself

PPE

Handwashing

Understand and observe pig behaviour

How to prevent harm to animals and public:

Inspect meat quality for disease and spoilage

Educate pig owners (pet pigs may walk too close to farms and spread disease)

Educate dog owners - may feed raw meat and catch disease themselves from the raw meat.

Biosecurity of farms

Biosecurity on pig farms

don’t spread disease from client to client

Pig farms have highest biosecurity

maintain a clean and dirty side on the farm

Approach youngest animals first as they have the weakest immune system.

African swine fever (ASF)

NOT ZOONOTIC

through: meat (cooked or frozen)

contact with pig/ body fluids

contact with contaminated people/ equipment/ vehicles.

not in UK yet

normal pig stats

HR: 90-110 BPM

Resp. rate of sow: 10-20 BPM

Resp. rate of piglet: 24-36 BPM

Rectal Temp: 38.5-40 deg. C

What does/ can clear discharge from vagina mean?

The pig is in heat - normal, not an issue

Results of disease in pigs

poor public health image

zoonotic infections

risk of AMR (antimicrobial resistance)

impacts farmers welfare (mental + physical health)

impacts animal welfare

reduces trade

reduces income

Veterinary health plan (VHP)

manage and improve pig health and welfare

Plan is unit (group of pigs???) specific (farm specific)

Reviewed quarterly by the vet to ensure it is being followed (eg/ has farm changed number of antibiotic uses)

maintain treatment protocols

Recommendations that may arise from Assurance and/or Welfare Schemes

Most Assurance schemes (like Red Tractor) require pig farms to have a VHP in place

Feed conversation ratio (FCR)

Performance measurement used in UK and some of the EU.

the amount of feed to produce 1kg of weight gain.

approx. 1.8kg food per 1kg wg for growers.

approx. 2.17kg food per 1kg wg for finishers.

measure the efficiency of feed mass conversion to body mass over a specific period

FCR= Feed consumed/ Liveweight gain

assessing health via weight

body weight used to ensure diet is correct.

used to assess reproductivity in gilts.

After this BCS is more common.

weaners = wean at over 7kg until 65kg then they are finishers.

Body condition score

measure of fat over the bone.

used for animals that aren’t continuously growing (piglets).

can use ultrasound to measure back fat depth

feel shoulder, hips, spine.

BCS vs weight

sow BC = weight and backfat thickness.

size variations = 2 sows don’t have same BCS.

taller/ longer sow with same weight = one is over conditioned or one is under conditioned.

over conditioned sows

when entering farrowing = dystocia (4.5-5 BCS) and lower feed intakes.

rely on fat reserves to produce milk.

extra joint/ leg strain.

under conditioned sows

(2.5 or less BCS) = not maintain pregnancy and have lower milk yields. - delayed oestrus (willingness to undergo sexual activity) post-partum.

under and over conditioning impacts:

losing BCS when farrowing (giving birth)

more ?inputs? to get back to 3 BCS

less piglets in later litters

muscular skeletal (MSK) influences

lameness

management + bacterial = main cause

infectious

clinical exam can be hard

3rd most common reason for antibiotic usage

sows not profitable after 3rd litter

boars culled if reproduction is hindered.

£1.5million a year in UK

Respiratory influences

infectious

management

Gastro-intestinal tract (GIT) influences

infectious

non-infectious

management

urogenital tract influences

management

reproductive failures and performance

viral

Musculoskeletal issues: Bacterial arthritis

Streptococcus suis = lives in pig tonsils.

gram + bacteria.

ZOONOTIC

can become pathogenic/ systemic infection

common disease:

meningitis + sepsis + bacterial arthritis

Risk factors:

overcrowding mixing different aged pigs.

poor ventilation + temp fluctuations

coinfections

Treatment + control:

antrimicrobials + vaccines

Gastro-intestinal issues: Swine dysentery

Caused by Brachyspira hyodysenteriae

causes weight loss + severe muco-haemorrhagic colitis (usually in growing pigs)

Transmission:

faeces and Contaminated surfaces (vehicles + people)

Expression influenced by diet:

reduced by more soluble fiber (sugar beet pulp)

reduce feed components with insoluble fibre (distillers dried grains)

Respiratory tract pathogens:

Causes = management based/ infectious agents (bacteria/ mycoplasma), Viral, parasitic.

usually more than one agent involved.

Highly contagious: direct/ aerosol contact/ indirect contact

secondary bacterial infection of lung tissue (~ £858m annually .

respiratory disease often very complex syndrome, multiple causes and long term herd issues. (effects reproduction)

Porcine Respiratory Disease Complex (PRDC)

14-20 weeks of age/ 8-10 weeks of moving into finishing.

Typical signs:

lethargy/ anorexia

fever

resp. signs (nasal discharge/ coughing)

Ocular (eye) discharge

Purple skin colour (often called blue ear)

often multiple viruses + bacteria species together

preventing PRDC

biosecurity policy

thorough cleaning of rooms

don’t mix pigs more than necessary

vaccination programs

units with history of it should create a swine flu control program with vet.

monitor temperature (consistent)

humidity below 70%

good ventilation -monitor ammonia levels (less than 50 parts per million (ppm))

reduce ascaris larval migration by implementing worm control plan.

Managements impact on reproduction

Gilts and sows:

delayed puberty due to modern housing

landrace + large white breeds = best in enclosed facilities (but more aggressive)

Anoestrus in weaned sows due to insufficient energy/ protein intake during lactation (especially in first litter).

Boars:

immaturity, lack of sexual experience, genetics, overuse, over-conditioning, pain when breeding.

(When more than 15% of the bred sows return to oestrus within 18 to 23 days, both male and female infertility must be investigated)

management/ equipment issues affecting reproduction

Contaminated/ dirty artificial insemination or incorrect semen storage.

Dirty breeding facilities

Not observing oestrus/ pig behaviour.

Porcine Reproductive and Respiratory Syndrome Virus (PRRSV)

Affects all aged pigs.

clinical signs:

weaners + growers + finishers = not eating, dull, red skin, labored breathing, rough hair coat.

Gilts + sows = return to oestrus, abortion, premature farrowing, mummified fetuses, stillbirths, pre-weaning mortality.

breeding sows 52% (£107/ sow annually)

piglets 47%

PRRSV transmission

introduced to herd via:

replacement pigs (new pig)

vectors (flies)

aerosol over short distance (nearby farms can work together to control disease)

spread by:

nose-nose contact

sow to piglet through pregnancy (more likely when infected later on in pregnancy)

contaminated needles (same one for whole herd)

fighting (saliva + blood)

through semen (vaccinate the boar)

contaminated clothes

vectors (flies and birds)

PRRSV control

screen the semen

only use replacements bred on farm (don’t introduce new pigs unless vaccinated)

isolate replacements offsite for over two weeks up to 8 weeks.

vaccinate breeding stock (use modified live vaccine if farm is in at risk area)