Lecture 18 Flashcards
What are factors affecting care of offspring?
- Size of litter
- Age of offspring
- Age of parent - younger parent (still growing, lack experience), older parent (may be last parity - devote extra care)
What did the family Pen system allow?
Allowed full range of behaviours:
* isolation
* nesting
* nursing
* rooting
This was not adopteddue to an increase in crushing of piglets, hard to keep track, more labour
Why are pigs a rare combination of parental care?
- r species (opportunistics) - can reproduce like crazy - ready for rapid pop growth with adundent resources
- Polygynous and precocial
- BUT: offspring/adult size ratio is low for precocial species - piglets have low reserves at birth
How many piglets can a sow produce?
21-28 piglets per sow per year
average is 12-14 because some dont survive
How does selecting for a nest site work in sows?
- starts 1-2 days before parturition (looking for an isolated area for nest building) - induced by hormones
- in a range of 5 - 10 km (safety - protected and isolated)
What is the function of nest building and what is it?
- Facilitates recognition of litter
- Sow treats litter as ‘an entity’
- Delayed individual recognition
- We use this in a production setting for cross-fostering
Highly motivated behaviour (internal) it is induced by hormone, increases oxytocin
What texture and temperature do piglets prefer when locating the udder?
warm and soft
How do farrowing crates limit sow behaviour and movement and why do we use them?
- Nest building
- Turning around
- Interacting with piglets
- stops crushing of piglets
How does feeding a litter work for sows?
- Parturition takes 1-3 hours
- Colostrum is available continuously for 6-8 hours
- Then sporadically, eventually only during nursing sequence
- Establishment of teat order within 3 days for whole litter
How does teat order work in piglets?
Established quickly after birth
* Piglets fight more during the 2nd hr after birth than during the 8th hr
* Individual piglet teat order: within an hour after birth and before the last piglet is born
* Litter as a whole: within 3 days
What are the nursing behaviours in sows?
- oxytocin level increases, sow grunts, let down of milk
- A sow nurses approx. every hour (nursing for 4-10 mins, nutritive nursing for 15-20 sec)
- Followed by period of non-nutritive suckling
- Milk production - piglets gain 20g each nursing
What teat do calves prefer?
highest part of underbelly, flank (shorter time suckling) beef was easier due to anatomy
What are parts of the parent-offspring conflict?
- offspring benefits from parents provision - the more the better
- the goals of the parent and offspring are different
- parents provide care depending on the payoff on investment and availability or resources
What do pigs spend most of their day doing?
Foraging - 60%
they are very active
pig commercial weaning age vs natural weaning age
Commercial - 4 weeks
natural - 60-100 weeks
