Swine Flashcards
1
Q
Class
A
- Mammalia
2
Q
Order
A
- Artiodactyla
- even-toed hooves
3
Q
Family
A
- Suidae
4
Q
Genus
A
- Sus
5
Q
Domesticated Pig
A
- Sus scrofa
- subspecies called Sus scrofa domesticus
6
Q
Chromosomes
A
- 38 chromosomes
- 19 pair
7
Q
Domestication
A
- early on, around time of sheep domestication
- 8000 BC
- separate domestication in E Asia and the Middle East (?)
8
Q
Global Number
A
- 1B
9
Q
China
A
- majority of pigs - 460M
- China lost half of its pigs to African swine fever
10
Q
US Number
A
- 60-70 M pigs
- avg 66M pigs
11
Q
Annual US Production
A
- 115M pigs
- short generation time of pigs
- at any given time, 60M pigs, but there are animals sent to market
- dynamic; numbers change rapidly, unlike cattle which take years to grow up and get into production
12
Q
Other Countries
A
- Brazil: 40+M pigs
- Germany/Europe: 27M
- Russia: 17M pigs
- most countries have their own pork production that is consumed domestically usually
- export of pork is less common
13
Q
US Regions of Pork Production
A
- Midwest because corn and soy is grown there, which is the main protein/food source for pigs
- Iowa: 20M pigs
- NC: 10M
- Minnesota: 8M
- Illinois: 5M
14
Q
Pig Farm Consolidation in US
A
- 60-70% of pigs are from 5000+ hog herd farms
- economy of scale
- pig farms are getting bigger and more large-scale
- pigs raised in barns bcs bad at temp regulation
15
Q
Boar
A
- male uncastrated pig
16
Q
Sow
A
- mature female
17
Q
Barrow
A
- castrated male
18
Q
Hog
A
- market pig above 50 kg
19
Q
Gilt
A
- young female before first birth
20
Q
Piglet
A
- young, milk-fed pig
21
Q
Farrowing
A
- giving birth
22
Q
Social Structure
A
- group or sounder
23
Q
Dental Formula
A
- 3/3, 1/1, 4/4, 3/3
- pigs are omnivores
- premolars might be really sharp
- break baby needle teeth to avoid them chewing on each other’s tails and from shredding teats
24
Q
GI Tract
A
- true monogastric
- nutrient absorption in small intestine
- water absorption in large intestine
- coiled colon
25
Pork
- red meat
- low levels of myoglobin, which binds oxygen, so meat looks paler
- sold as white meat to compete with poultry industry
26
Female Puberty
- 5-7 mo
- 100 kg
27
Estrous Cycle
- 21 days
- polyestrous
28
Uterus
- bicornuate uterus
- extra long uterine horns because whole litter needs room to sit inside the uterus
29
Placenta
- diffuse, like mares
30
PG 600
- hormone injection
- gonadotropin that releases FSH and LH to initiate onset of follicle formation in the ovary
- can induce ovary to start cycling
- used to synchronize sow heat cycles
31
Lutalyze
- injection that lyses the corpus luteum from being functional at certain time
- resets estrous cycle and has them all resynchronize to get ovulation at the same time
32
Matrix
- ingested like oral contraceptive
- mimics progesterone
- suppresses ovulation while eating it; when they stop, they start ovulating several days later
33
AI Success
- if she's in heat 21 days after insemination, she didn't get pregnant
- if pregnant, do ultrasound 30-60 days after breeding
34
Boar Penis
- fibrous; sigmoid flexure like boar and ram to extend penis
- corkscrew penis that locks into cervix of female for prolonged ejaculation
35
Ejaculation
- 5-15 mins
- 150-300 mL ejaculate
- 30-60B spermatozoa per ejaculate
- need large volume of ejaculate to make it up uterine horn
36
Testes
- 750 g
- external because pigs are bad at temperature regulation
- need to keep testes cool
- cool blood flows through because heating of spermatozoa can damage/kill it
37
AI Method
- most pigs in US bred by AI
- boars hump something like stallions' phantom
- you stimulate the boar and then collect ejaculate for 5-15 mins in a container
- inspect sperm morphology, motility, life, etc., once collected
- put into aliquot tube to deliver into catheter that locks into cervix
- semen is fresh and cooled for optimal viability
- 1 boar per 20 females in natural service
- 1 boar per 50 females in AI
- keep boars on farm to collect semen and detect heat
38
Generation Interval
- short
- gilt bred by 6 mo
- 114 day pregnancy
- generation interval of 10-11 mo
39
Genetic Gain
- when you select individuals for genetic advantage, shorter generation interval means increased genetic gains
- can select best ones out of F1 generation
- faster in swine than in cattle
40
Lactation Period
- 21 days
- lactational anestrus (does not ovulate until weaned)
41
Litters
- 2.2/yr
- allows you to market more pigs per year
- greater ability to realize genetic gain
- operational efficiency
42
Farrowing
- 18-21 piglets
- 12-14 teats, so might need to cross-foster for colostrum delivery
- injection of oxytocin for muscle contraction of myometrium
- oxytocin is the "quick birth hormone"
43
Myometrium
- muscular layer of the uterus involved in contractions
44
Farrowing Crates
- sometimes stalls for a bit more freedom
- with more sow maneuverability, greater risk of pig mortality
45
Heritability (H^2)
- (variance in genotype) / (variance in phenotype)
- fraction or proportion btwn 0-1
- how much of phenotypic variance is genetic vs. environmental
- high heritability means next generation will likely have same trait
- lowest heritability = litter survival to weaning (5%)
- high heritability = backfat thickness (40%)
46
Backfat Thickness
- 40% (high) heritability
- quantitative trait
- thickness of fat under skin and btwn skin and muscle layer across back/top of ribs
- use ultrasound to measure in live animals
- measure thickness in carcass and backtrack to the sire or dam of that pig and breed more of those offspring
47
Litter Size
- can select for more offspring
- quantitative trait
48
Growth Rate
- measure thru dorsus longissimus muscle (loin muscle)
- loin muscle tends to be long and skinny
- loin eye area = cross section of loin muscle
- larger loin eye area = expect all muscle groups of that animal to be larger
- want max growth rate --> max feed efficiency --> max feed conversion ratio (amt fed/amt gain)
49
Feed Conversion Ratio of Pigs
- 5 kg of feed = 1 kg of meat
50
Terminal Sire
- permanently ending that genetic combo
- the offspring of a terminal sire go straight to market; no further breeding of F1 gen because the heterozygous genotype would lose the purity of the breed
- keep up pure genetic lines for breeding, just like with dairy
- Duroc boar is terminal sire for market pigs
51
Heterosis
- hybrid vigor
52
Undesirable Traits
- too much fatness (leads to less energy for growth, incr dystocia, infrequent estrous cycle
- HAL (halothane) gene)
53
Halothane (HAL) Gene
- this one boar had really fast-growing piglets, so used to breed a lot
- piglets had porcine stress syndrome (PSS) -- seizing, convulsing, flushed
- had been selecting for animals w/ mutation in ryanodine receptor gene, so muscles didn't function properly under stress
- animals would have pale, soft, exudative (PSE) meat -- carcasses of no use
- mutation of allele spread throughout swine population
- exposed pigs to halothane (anesthetic gas)
- pigs w/ stress response of convulsions had PSS and the HAL gene (looked at phenotype to determine genotype)
- PSS is recessive-inherited
54
Piglet Processing
- clip tail
- iron dextran injection for immunity
- clip needle teeth (avoid teat damage)
- castrating to avoid boar taint from hormones
- ear notching (1, 3, 9, 27, 81 - to cover whole scale)
- may administer antibiotics, especially for scours, but not very common; might vaccinate
55
Scours
- diarrhea
- might use antibiotics preventatively, but less common
- use antibiotics less to avoid drug resistance increasing in bacteria/virus pops
- animal industry using antibiotics impacts human population
- might vaccinate for scours instead
56
Nursing
- piglets nursed hourly
- sows synch feeding behavior
- sows lay down, grunt
- piglets stimulate teats --> release oxytocin --> milk letdown
- different feeding from dairy calves, who are separated from their mother and nursed w/ a bottle
57
Creep Feed
- supplemental solid food to get piglets' digestive system enhanced so once weaned (18-21 days old), they can eat solid food in nursery
- weaning is one of the most stressful periods for young animal (separated from mother, weaned off milk)
- greater chance of disease, drop in growth with weaning
- minimize stress in transition w/ creep feed
58
Number of Pigs Weaned Per Litter
- can select for greater live litter sizes, but also need to select for sows who wean most of the piglets produced
- mothering ability (if poor, less milk production)
- preweaning causes of death: sows crushing piglets (minimized by farrowing crates), poor temp regulation (use heat lamps)
59
Nursery
- 8 weeks spent in nursery (until 11 weeks old)
- enrichment (to avoid fighting among group-housed littermates --> more fighting = less growth)
- optimize feed for growth
60
Piglet Feed
- muscle growth requires protein to build myosin and actin
- need amino acids (soy, corn), especially lysine
- high-protein diet
- need Ca and P for bone growth
- need energy (ad libitum supply of feed)
61
Growing and Finishing
- next 3-4 mo after nursery
- to make animal meet market reqs
- just enough fat for taste (optimize fat ratio w/ diet)
- ad libitum feed, but not excess fat
- feeding diet that has 3300 kcal/kg of metabolizable energy
62
Aflatoxins
- can contaminate feed if feed gets wet and pathogens populate it
- these toxins decrease growth, can lead to abortions
63
Pig Market Weight
- 110 kg (220-250 lbs)
- 66% dressing percentage
64
Dressing Percentage
- how much of its overall body weight is the carcass = body less the viscera (digestive and reproductive system) and extremities
- (carcass)/(live weight) = dressing percentage
- live weight of animal can differ
- gut fill – food in the stomach
- water (body) – amount of water in body
- rumen in ruminant can take so much fluid – big change
65
Housing - Enclosed Structures
- lot of pigs are raised in Midwest in enclosed structures
- for climate control (because pigs are bad at temp reg)
- biosecurity (shower in, shower out -- why African swine fever didn't get into US)
66
Farrow to Finish Operation
- sows to nursery to finishing
67
Farrowing in One Farm to Nursery in Another Farm to Finishing in Another Farm
- breaking up lifecycle allows amplification
- nucleus herds (breeding farms) --> piglets --> sent to different ops
- becoming a bit more common
- allows genetic gain and limits disease spread
