3.7 Feeding Lactating Sows - T3 Flashcards
What are the 2 main objectives for lactating sows? What might these mean for energy intake?
- Maximize litter performance
- high milk production
- minimal mobilization of maternal body tissue - Long term productivity
- successful rebreeding
- reproductive longevity
Want to maximize energy intake during lactation by maximizing feed intake
What are 3 important factors of FI for lactating sows to consider?
- Key aspect of nutrition of lactating sow
- but challenging bc sow is very stressed and need tissues to shrink after farrowing
- limiting factor for milk production - Milk production limits
- piglet growth and survival - Maintain body composition
- for easy rebreeding
- for longevity
FI during lactation (from gestation to early lactation)
- FI in gestation
- avoid overfeeding; by increasing fat reserves the FA arriving at the brain increase which signals a cascade to reduce FI - Postpartum FI depression
- lethargy, stress
- limited gut volume - FI increases gradually in lactation
What is the critical factor for successfully increasing FI directly after farrowing?
Have sows at ideal body condition at farrowing
How does feed intake differ between parities?
Feed intake increases from 1st to 6th parity
- heavier multiparious sows -> higher maintenance req
How does FI change with litter size?
FI increases with litter size
What does FI differ with for lactating sows?
- Parity
- Litter size
- Genotypes and farms
What happens if sows are overfed in gestation?
High backfat = high lipid in blood = signals satiety
What happens if sows receive a low protein diet during gestation?
May reduce lactation feed intake
What factors affect lactation FI and how?
Overfeeding sows in gestation will decrease their FI during lactation
A sow that has a ___ FI during gestation tends to have a ___ FI during lactation
- higher/lower
- lower/higher
What is the lactation feeding strategy?
- Switch to lactation diet when sows are moved to farrowing crate
- After farrowing set up feed allowance quickly
- reach ad libitum within 7-9 days - Remaining lactation
- fed ad libitum - After weaning: ad libitum dry sow diet
- to recover BW losses and be able to be bred again more easily
What is the limiting factor to temperature and FI? How can pigs be kept cool?
Ability to dispose of HI
- drip coolers or snout coolers
- heat conductive flooring
- diets with low HI
What are 3 strategies to reduce HI when formulating diets?
- reduce fiber
- reduce protein
- increase fat
Other than temperature, what are 4 other factors affecting FI?
- Air quality
- Light
- 16h of light promote higher FI than 8h - Feeders, feeding and feed
- bowl type
- feed more than once a day
- pellets
- wet better than dry
- high energy diets - WATER!
- need sufficient water flow
Milk energy content
- 30-40% fat on DM basis
- impact of litter size
- efficiency of energy utlization
Lysine (AA) in milk
- important for litter gain; in order for piglets to deposit protein they need to get Lys
- body mobilization; high aa and protein to minimize amount of lean mass lost from sow during lactation
How is milk production estimated?
By indirect methods
- weigh-suckle-weigh
- litter weight gain
What 4 factors affect milk production?
- Milk yield
- genotype
- peaks in wk 3-4 - Sow: size, body reserves, nutrition, parity
- higher parity sows produce more - Piglets: number, weight, vigor -> suckling stimulus
- Fat sows may produce less milk than lean sows
What happens to milk composition as time passes following farrowing? (fat, lactose, protein, IgG’s, energy)
Fat%: increases
Lactose%: increases
Protein%: decreases
IgG’s: decrease
Energy: decreases
More milk =
Higher nutrient output = higher requirements
- must ensure diet is more nutrient dense or maximize sow’s FI so she can sustain milk production without losing BW
What 3 factors affect nutrient requirements of lactating sows?
- Sow maintenance
- Milk production
- accounts for daily litter gain and litter size - Change of sow BW and composition
- losing body lipid -> energy
- losing body lean -> energy and AA
Body weight loss composition of lactating sows
Typically
- 60-70% fat
- 9-14% protein
Ratio of fat to protein loss depends on
- dietary protein: energy ratio
- milk production
- body composition
- metabolic need of sow (older sows have higher metabolic needs)
Body weight loss and performance
Backfat loss
- target: minimum 10 mm backfat
- lower than that can reduce milk production
Protein loss
- acceptable: 10-12% of body protein mass
- higher than that -> reduced milk prodution
Greater body losses -> longer wean-to-estrus interval
How can we increase energy intake for lactating sows?
- Increase FI
- Increase energy density of diets
Are AA requirements or energy requirements easier to satisfy for a lactating sow?
AA requirements
- use high energy diets with sufficient amino acids to cover requirements and achieve the highest energy intake possible
What should lactation diets be high in?
- High in energy
- High in protein and lysine
- High in calcium (for milk production and prevention of excessive bone calcium loss)
What is the greatest factor for requirements of lactating sows?
Milk production
Req = maintenance + milk production + change in body comp
