8. Pig behaviour and welfare

Question 1

importance of smell for pigs

Answer 1

– Highly sensitive and dominant sense along with hearing
– Wide range of olfactory cues: recognizing dam & teat position; individual identities
– Can be used to increase palatability of feeds

• Pheromones
  – Maternal
  – Androstenone (boar saliva)

Question 2

importance of hearing for pigs

Answer 2

– Large hearing range (40 - 40,500 Hz) & localization abilities

– Vocalizations:
* Very vocal communicators: 5 separate call types identified
* More higher frequency calls (>1000 Hz) are indicator of acute pain in piglets (severing of spermatic cord during castration)
* Major way (along with olfactory cues) on how pigs communicate

Question 3

importance of taste for pigs

Answer 3

– Pigs in nature are opportunistic omnivores
– Can identify sweet, salty, bitter and sour but will reject foods that taste bitter; sweet, cheese & meaty were most preferred
– Use flavoring to entice solid feed consumption at weaning

Question 4

wallowing in pigs is for what reason

Answer 4

to prevent sunburn

Question 5

sense of sight in pigs

Answer 5

• Panoramic vision of 310o, binocular vision of 35-50o
• Have rods and cones sensitive to green and blue frequency
• Will hesitate or be frightened by objects in path and prefer going towards lighted areas

Question 6

Social Organization of pigs

Answer 6

– pigs organize themselves into multi-family units of ~8 sows with offspring, boars are solitary
– will have large communal nests with no dominance for sleep areas but then separate into sub-groups for foraging in the day
– Tend to be diurnal in activities and feeding

Question 7

types of social organization in pigs

Answer 7

1. Teat order
2. Dominance hierarchies

Question 8

important behaviours from birth through weaning

Answer 8

• Nest building: sows are highly motivated, regulated internally & externally
  – These behaviours are severely restricted by the use of farrowing crates
• Complex nursing and suckling behaviour
  – Nursing occurs ~1x/hr and milk letdown is stimulated by
  piglets

Question 9

procedures done for piglet processing

Answer 9

• Piglet processing involves teeth clipping, ear-notching, castration, tail-docking & iron injection
• Considered elective and painful under the Codes of Practice

Question 10

teeth clipping rationale

Answer 10

done to reduce injury to littermates and/or sow; is the cutting off of the tip or entire external section of canine & 3rd incisors (i.e. “needle” teeth)

Question 11

rationale of ear notching/tatooing

Answer 11

Ear notching/tatooing: to identify individual animals
Notching is considered painful & tatooing stressful

Question 12

requirements for teeth clipping

Answer 12

The need to clip piglets’ teeth must be evaluated, and the
procedure performed only when deemed necessary.

Question 13

requirements for ear notching

Answer 13

Ear notching must only be performed on piglets when deemed necessary and when piglets are less than 14 days of age.

Question 14

rationale for surgical castration at weaning? reccomendations?

Answer 14

to prevent boar taint & aggression in males

Recommendations: (1) have a veterinarian perform if over 23 kg (2) use non-surgical methods such as immuno-castration

Question 15

requirements for castration of piglets

Answer 15

Castration performed after 10 days of age must be done with anesthetic and analgesic to help control pain.

As of July 1, 2016, castration performed at any age must be done with analgesics to help control post-procedure pain.

Question 16

rationale for tail docking

Answer 16

to reduce the risk of tail-biting behaviour

Question 17

what is tail biting behaviour and why is it a problem?

Answer 17

destructive chewing of one pig’s tail by another pig;
* Serious wounds, infection, paralysis, and in extreme cases death can result
* Multi-factorial etiology
* Serotonergic system involvement

Question 18

requirements for tail docking

Answer 18

Pigs must be routinely monitored for signs of tail-biting, and corrective action, as necessary, must be taken (e.g. assess possible contributing factors; remove tail-biter; add rooting and/or physical enrichment).
Tail docking of pigs over 7 days of age must be done with pain control.
As of July 1, 2016, tail-docking performed at any age must be done with analgesics to help control post-procedure pain.

Question 19

when does weaning occur and what does the process look like?

Answer 19

• Industry standard is ~21 d (~11-17 wks in nature)
• Piglets experience numerous stresses simultaneously (nutritional, emotional, immunological & physiological)
• Use of creep diets to facilitate feeding before weaning

Question 20

requirements for weaning

Answer 20

REQUIREMENTS (feeding)
All newly weaned pigs must have continuous access to fresh feed and feeder design must be appropriate for the size of the pigs.
All newly weaned pigs must be observed frequently in the period following weaning to ensure that all are eating.

REQUIREMENTS (weaning)
Weaning procedures that minimize negative impacts on the health and welfare of the piglets must be developed and followed.

Question 21

Weaning Problems

Answer 21

mixing aggression
belly nosing

Question 22

what is mixing aggression?

Answer 22

weaning problem

fighting between newly mixed pigs is common and intensity decreases within first hrs, stressful & can prevent certain pigs from eating or drinking

Question 23

what is belly nosing?

Answer 23

weaning problem

abnormal behaviour of rubbing snout on the midsection of another piglet; typically develops in 1st week of weaning but only in some piglets; etiology is not understood but may be a possible redirected suckling or redirected rooting and exploratory behaviour
* More in barren environments
* More prevalent in earlier weaned piglets
* All theories include a component of frustration or stress

Question 24

what is the growing period and what behavioural problems do we see here?

Answer 24

Growing period: when pigs reach 25 kg, they move onto the grower period of production (i.e. “Grower” pig);before finisher phase of production
* New feeding regime & environment
– space allowance & feeder:pig ratio

Behavioural problems: tail-biting & ear-biting

Question 25

welfare concerns during the finisher phase

Answer 25

Finisher phase: last stage of production; change in diet Welfare concerns: transportation & slaughter

Question 26

what is a compromised animal

Answer 26

has a reduced capacity to withstand the stress of transportation for various reasons (e.g. injury, fatigue, infirmity, poor health, distress, very young or very old age, impending birth).

Question 27

transportation considerations

Answer 27

lighting, gradient of ramp, extremes of temperature, stocking density, aggression (boar’s must not have tusks), handling, [feed withdrawal]

Question 28

finisher phase requirements for loading and transportation

Answer 28

• Unfit animals must not be loaded.
• Compromised animals that are able to be transported under special provisions must be shipped
  directly to local slaughter, not through auction markets.
• Animals that cannot bear weight on all four legs must not be loaded; these animals will likely become non-ambulatory during transport.
• Fitness for transport in the context of each trip, including relevant factors such as the anticipated total trip duration from farm to final destination, and prevailing weather conditions, must be evaluated.

Question 29

breeding herd housing types

Answer 29

Housing: gestation crates & group housing

Question 30

when do we see aggression in the breeding herd

Answer 30

Aggression: with mixing of sows & introduction of new gilts to groups

Question 31

behavioural vices of the breeding herd

Answer 31

chain
chewing, bar-biting, vacuum
chewing & polydipsia

Question 32

requirements for the breeding herd

Answer 32

For all holdings newly built or brought into use for the first time after July 1, 2014, mated gilts/sows must be housed in groups. Individual stalls may be used for up to 28 days after the date of last breeding and an additional period of up to 7 days is permitted to manage grouping. Time in stalls can only be extended to protect the welfare of individual sows on the advice of a competent stockperson.

Question 33

safe handling and moving of pigs

Answer 33

• Intelligent, stubborn and vocal (ear protection)
  – Cannot herd pigs but can use food for luring
  – Larger pigs can be dangerous (esp. while restraining, in pain/scared, handling/processing piglets, when aggressive with each other)
  – Good to have escape route and let people know if you’re working alone
  – Use pig boards for protection & for moving
• When stressed easily become hyperthermic
• Important to be slow and gentle

Question 34

Advances & Opportunities to improve pig welfare

Answer 34

• Immuno-castration: A method of castration which is reversible and non-painful. Accomplished by immunizing against sex hormones
• Sexing of sperm: The ability to select for either male or female offspring