3.6 Feeding Gestating Sows - T3 Flashcards
What 3 things do we have to consider when estimating requirements for gestating sows?
- Maintenance - highest priority
- 75-85% of total energy needs - Conceptus growth - highest priority
- fetal, uterine and mammary growth - Maternal growth - extra nutrients
- 15-25% of total energy needs
- may use body lipid to support protein growth when limited by energy but there’s enough protein in the diet
What is the relationship between maintenance requirements and parity?
Maintenance requirements increase with parity
- bc sows are getting heavier = higher metabolic body weight
What happens if we feed the same diet at the same level throughout the gestation period?
Overfeeding sows at beginning, underfeeding at the end
Why does ideal AA profile change? Can we feed sows and gilts the same diets?
- Requirement for growth is greater for younger sows; for older sows they have higher maintenance requirements
- Usually avoid feeding sows and gilts the same diets
What do Ca and P requirements change with?
Increase with fetal growth
- maximal in late gestation
- if diet is deficient, sow can’t mobilize sufficient Ca so piglets contain less Ca
What are Mg, Zn, Mn, and Cu, I, Fe important for?
- Mg
- reduce weaning to estrus interval, increase piglets born and weaned - Zn deficiency
- decreased piglet viability (immune system) - Mn
- increased piglet ADG - Cu, I, Fe
- insufficient data for sows -> use GF
What 3 fat-soluble vitamins are important for gestating sows? Why?
- Vit A
- oocyte maturation, [progesterone], embryo survival - Vit D
- skeletal soundness, ovarian tissue may be target - Vit E
- smaller litters, prolonged farrowing, less milk
What 6 water-soluble vitamins are important for gestating sows?
- Biotin
- foot condition - Choline
- increased conception rate - Folate
- DNA synthesis
- reduce embryo mortality, increased piglets born - Pantothenic acid
- Riboflavin
- Niacin, thiamin, B6
What determines feed allowance for gestating sows?
Body condition scores
- we want 2.5/3
- based on a visual
- other ways: tape measurement, ultrasound
What are the 4 pros to individual feeding? Are we allowed to use this?
- Gestation stalls = control over FI
- Feed sow to condition
- Saves feed cost
- Avoids fighting
NO LONGER ALLOWED TO USE THIS
Unless automated electronic feeding systems are used, what happens when sows are group fed?
- Sows high in the hierarchy eats most feed
- Lower ranked might not eat enough
- Need to increase feed allowance 10-15% over individual housing
What allows sows to be individually fed in a group housing system?
Automated electronic feeding systems
How often are sows fed? What happens if feeding frequency is increased? Automated electronic feeding systems might be set to spread out feeding across the day, why?
- Industry standard is once a day
- Increasing feeding freq = greater activity = greater energy expenditure
- no effect on sow performance - Gives the sows something to do twice a day so there is less fighting
Gestating sows are feed restricted. But what would be the advantages of increasing the bulk of a low energy diet? How?
- Diet with 60% beat pulp (fiber) ad libitum = no weigh difference at weaning and no difference in repro performance
- But more expensive per sow, may be viable if cheap source of low energy feedstuff is available
- Fiber fermented by gut bacteria = SCFA = good for gut health
- Increases stomach size = good for lactation
What are the advantages and risks of feeding a single diet for all sows at all stages of gestation? What do you have to be critical of?
Advantage: simple and easy feeding program
Risks: underfeeding some sows, overfeeding others
Critical: assessment of feeding level at breeding
How are gestating sows phase fed?
Same diet -> change feed allowance
Early gestation
- little requirements for fetuses
Mid gestation
- increase feed allowance; fetal muscle development
- may increase lean in female slaughter pigs
Late gestation
- fetal and udder growth
- Increase FI -> increase litter wt at birth and weaning
Diet formulation according to parity
- 1st and 2nd parity need GREATER protein (AA) content
- 1st parity needs greater maternal gain to achieve target back fat
- Lys content in diets for older sows can be reduced
- Ideal protein is different for gilts and older sows
SO: feed separate diets
- to optimize growth in gilts
- to minimize cost for older sows
Why is maternal gain and protein gain reduced in older sows (older parity sows)?
- Sows aren’t growing anymore bc they have reached their maximal BW/size so protein gain is reduced
Fat and fiber prior to farrowing
Fat -> may reduce weaning mortality if we supplement it into the diet at the end of gestation
- FA directly incorporated into fetal body fat for additional energy at birth
- saturated medium-chain FA best bc easy for piglets to oxidize
Fiber -> full feed allowance bc bulky ingredients may increase stomach volume
- greater FI during lactation
- reduce constipation
- reduce the risk of low milk production
When formulating diets for gestating sows, what priorities are we considering?
- Maintenance
- Conceptus = uterus & mammary glands
- Maternal growth
- Lipid deposition (lowest priority)
