swine exam 2 Flashcards
maternal pig breeds
landrance, large white
(selected based on litter size and mothering ability)
paternal pig breeds
: pietrain, duroc, Hampshire, white synthetic
-: selected for growth, feed efficiency, carcass and meat quality.
pigs gestation
114-117 days
4 stages of production and times
- Breeding/gestation: gestation 114-117 days
n Farrowing: where sows furrow and nurse there litters 3-4 weeks
n Nursery: where weaned pigs are raied 5-8 weeks
n Grow-finish: where pigs are raised after nursery before slaughter 16-18 weeks.
feeder vs market pig sizes
n Feeder pig – a pig old enough to enter the grower barn (25kg)
n Market pig – a pig large enough to be processed
n 115-125 kg live weight, 5-6 months of age
production flow of pig barns and times
-gilt development -> breeding and implatation (35 days)–> gestation 12 weeks–> farrowing 4 weeks.
-sow goes back to breeding and implantation barn. then piglets taken to nursery (6-8 weeks) where they are raised until old enough to go to grower-finisher barn until they go to slaughter. 16 weeks
humane slaughter process
-delivery to plant by producer, traceable with tattoo on L shoulder which identified each farm.
n Assembled put together in “yard” for 12-18 hours
n Stunned by electrocution or C02
n Shackled
n Exsanguinated (via vena cava/jugular)
n Scalded, dehaired & washed
n Eviscerated
n Inspected, weighed
n Halved & chilled
pig flow systems continous flow or all in all out
-continuous flow system: can lead to disease, all sharing air. Coming into contact with new piglets and older and younger animals. dynamic pop.
-All in all out system: piglets are weaned and stay together as a group with the same immunities ect. So we don’t have sharing of pathogens at the wrong time. static pop.
5 freedoms for assesing pig housing
1 freedom of movement
2 freedom from aggression
3 control over individual feed intake
4 provision of environmental encrichment
5 provision of static space requirements
lighting in pig barns
-pigs are seasonal breeders farrow in spring
-stimulated by shortening photoperiod
-most fertile in autum to winter
-seasonal infertility in summer
-16 hours day light to attempt to prevent seasonal infertility
barn temp breeding
◼ “Effective” vs. “ambient”
◼ Optimum 16-18oC (range 10-27oC)
◼ Warmer temperature required in stalls due to inability to escape adverse air flow
and/or floor moisture
◼ Pregnant sows are prone to heat stress (sweat glands on nose only)
◼ Drip nozzles & misters can be useful if increased airflow to create evaporative
cooling is provided
◼ Regions of prolonged hot summers
breeding gilts
Advantage of delaying breeding
Litter size increases by about 0.5 pigs for each subsequent estrus
(E1, E2, E3) but must be balanced by additional housing and feed
◼ Common guidelines for first fertile breeding on commercial farms:
◼ Minimum 220-240 days of age
◼ Second observed estrus on farm, skip first estrus
◼ Optimum weight (~135 kg)
how is breeding done
◼ Typically estrus cycle occurs 4-7 days after weaning
◼ Confirm receptivity to boar visenctimized boar goes around and stimulates sows.
◼ Inseminate or breed naturally once per day until out of standing heat (generally 2-3 matings total)
semen production
◼ AI stud or on-farm
◼ CFIA regulated
◼ Fresh, 16-17oC storage, protected from UV light
◼ Usually pooled (collections from multiple boars combined)
◼ 2-3B sperm/dose, 2-3 doses per female
◼ Many extenders with shelf-life 3-14 days
◼ Sexed semen now commercially available through 1 supplier
confirming preg
◼ Estrus (heat check) with boars at day 21 & 42 (best way with good staff)
◼ Pregnancy examination day 25-35 depending on equipment
Non-pregnancy
◼ Conception failure – return to service at 21 (+/- 3) day intervals
- Regular returns (18-21, 39-45 d) no conceptus recognition not pregnant
◼ Pregnancy failure – after maternal recognition of pregnancy