Feeding Strategies for Prolific Sows ?????????

1
Feeding Strategies for Prolific Sows?????????

• P.A. Thacker
• Department of Animal Science
• University of Saskatchewan
• Saskatoon, Saskatchewan
• ???????????????
• ??????ADM?? ???

2
Changes in the Swine Industry (1980-2005)???????
(1980-2005)

• Increased Reproductive Efficiency
• ?????
• Reduced Back Fat Levels
• ??????
• Earlier Weaning ????
• Muti-Site Production ????
• Larger Operations ????
• Lower Profit Margins ??????

3
Feed Modern Genotypes Differently ??????????????
4
Conserve Body Tissue ?????
5
Consequences of Poor Sow Nutrition?????????

• Smaller Litter Size ???
• Increased Piglet Mortality ???????
• Lighter Pigs at Weaning ?????
• Lower Conception Rates ????
• Longer Weaning to Rebreeding Interval
• ?????????????
• Premature Culling ????

6
Formulate Diets for Specific Stages of
Production ?????????
7
Gilt Developer Diets??????

• Developer diets typically contain higher levels
  of vitamins and minerals than those fed to market
  animals since the nutritional requirements for
  growth and reproduction are different.
  ????????????????,???????????????????????????????
• The higher levels of vitamins and minerals are
  designed to enhance body reserves of nutrients
  since breeding animals will remain in the herd
  for a significantly longer period than market
  animals. ?????????????,???????????????????????????
  ?

8

• Locomotor problems are a common reason for
  culling and it is important to ensure adequate
  intakes of calcium and phosphorus.
  ????????????????, ?????????????????????
• Several research trials have indicated that the
  calcium and phosphorus requirements for maximal
  bone mineralization are higher than the
  requirements for maximal growth rate.
  ????????,?????????????????????????

• Diets fed to replacement gilts should be at least
  0.1 higher in calcium and total phosphorus than
  diets fed to market animals beginning at
  approximately 50 kg body weight.
  ?50kg????,???????????????????0.1?

9
In addition to higher levels of calcium and
phosphorus, there is antidotal evidence that
supplementing the gilt developer diet with higher
levels of copper, zinc, iron, iodine and
manganese will increase body reserves of these
minerals and may enhance future reproductive
performance. ??????????????????
??????????????
???????????,??
??????????????
?????????????? ???
10
Recommendations for Mineral Fortification of a
Gilt Developer Diet Compared with a Typical
Finisher Diet????????????????????????
Typical Gilt Finisher Developer ???
???? ???? Macrominerals (Total) ?
Calcium 0.60 0.75 ? Phosphorus 0.50 0.65 ???
Avail phosphorus 0.20 0.40 ??
Salt 0.33 0.40 ???? Microminerals
(Supplemented) ? Iron mg/kg 50 150 ?
Copper mg/kg 10 15 ? Zinc mg/kg 90 150 ?
Iodine mg/kg 0.14 0.28 ? Selenium mg/kg
0.30 0.30 ? Manganese mg/kg ---- 20
11
Vitamin Levels for Developer Diets????????????

• The vitamin needs of the reproducing female are
  also greater than those of the terminal animal.
• ?????????????????
• The typical vitamin premix used in the finishing
  barn should be replaced with a breeder vitamin
  premix.
• ???????????????????????????????
• The breeder premix should contain elevated levels
  of the fat soluble vitamins A, D, and E and the
  water-soluble vitamins with special attention to
  choline, biotin, pyridoxine and folic acid which
  are usually not supplemented in typical finishing
  rations.
• ????????????????????A?D?E?????????,???????????
  B6??????????????????????

12
Recommendations for Vitamin Fortification of a
Gilt Developer Compared with a Finisher
Diet????????????????????????
Typical Finisher Gilt Developer

??? ???? Vitamin
A IU 5500 8200 Vitamin D IU 550 825 Vitamin
E IU 25 66 Vitamin K mg 2
2 Vitamin B12 ug 15 25 Niacin ?? mg 20
20 Pantoth Acid ?? mg 15 20 Riboflavin B2
mg 4 20 Choline ?? mg 0 1250 Biotin
??? ug 0 200 Folic Acid ?? mg 0
1.5 Pyridoxine B6 mg 0 1.0
13
Feeding Gilts ???????
The objective of any feeding strategy for gilts
should be to introduce replacements into the
breeding herd in such a way that their breeding
lifetime and reproductive performance are
maximized. ???????????????????????????????????????
????
14

• It is important that replacement gilts be of
  sufficient age, size and physiological maturity
  before breeding.
• ????????????????????????????????
• It is also necessary that they have adequate
  reserves of fat and lean in their body at first
  mating.
• ????????????????????????????????

15
Targets for Gilts at First Mating???????????????

• At least 135 kg live weight
• ??135?????
• At least 16-20 mm P2 back fat
• ??P2????16-22??
• At second estrus or later
• ?????????????

16
Reproductive Performance of Sows According to
Body Weight and Back Fat at First
Mating????????????????????????
Body Weight P2 Backfat at Number of Piglets
Born at Mating (kg) Mating (mm) Parity 1 Parity 1
to 5 ????? P2????
????? 1-5????? 117 14.6 7.1 51.0 126 15.8
9.8 57.3 136 17.7 10.3 56.9 146 20.0 10.5 59.8 157
22.4 10.5 51.7 166 25.3 9.9 51.3 Challinor et
al., 1996
17
Feeding Replacement Gilts From Herd Entry Until
Mating ???????????????
18

• For most genotypes of gilts there is no need to
  do anything special to manipulate body
  composition. ?????????????????????????????
• All that will be required will be to feed a gilt
  developer diet ad libitum from arrival in the
  breeding herd until mating.
• ?????????,??????????????????????????????
• This diet should contain about 3000-3200 kcal of
  DE/kg and 0.70-0.80 lysine. ?????3000-3200??/kg?
  ???0.7-0.8????

19
Nutrient Levels to Maximize Lean TissueGrowth
Rates in Developing Gilts????????????????????
Body Weight of Gilt ??????
10-20 20-50 50-100 DE Intake (Mcal/day)
3.4 6.40 9.0 ??? (??/?) Crude Protein ()
??? 20.9 18.0 16.3 Total Lysine () ????
1.15 0.95 0.75 Total Lysine (g/day ?)
11.5 19.0 22.5 g Lysine/Mcal DE
3.38 2.96 2.50 ????/????? Adapted from NRC
(1998). Assumes ad lib intake and a lean growth
potential of 325 g/day ??????????????325?/??
20

• For genotypes whose growth rate is so rapid that
  they are likely to be significantly over the
  target weight before reaching puberty, it may be
  necessary to restrict energy intake.
• ????????,??????????????????????????,?????????????
  
• The objective of restricting energy intake during
  rearing is to limit mature body size and reduce
  feet and leg problems associated with females
  that become too heavy or too fat. There are two
  possibilities to accomplish this
• ?????????????????????????????????????????????????
  
• 1. Restrict Feed Intake (2.4-2.6 kg) ??????
• 2. Reduce Energy Density ??????

21
Effect of High Fibre Gestation Diets on
Reproductive Performance?????????????????
Standard 50 Sugar 50 Mixed Gestation
Diet Beet Pulp Fibre Sources
??????
50??? 50????? Net Energy Content
(MJ/kg) ???? 9.03
8.49 6.72 Gestation Feed Intake (kg) ??????
281 290 368 Gestation Energy Intake (MJ NE)
2296 2216 2287 ??????? Lactation Energy
Intake (MJ NE) 1450
1528 1438 ??????? Gestation Weight Gain (kg)
?????? 58.7 61.6 67.9 Lactation Weight
Loss (kg) ?????? 8.0 6.3 9.6 Pigs Born
Alive ????? 10.8 10.9 10.7 Birth
Weight (kg)??? 1.6 1.5 1.7 Pigs
Weaned ????? 9.5 9.3 9.3 28 Day
Weaning Weight (kg) 8.4
8.1 8.4 28????____________________________________
_____________________________ Vestergaard and
Danielsen, 1998. Animal Science 68
355-362. Mixed Fibre Grass meal, wheat bran and
oat hulls. ???? ???????
22
Feeding Replacement Gilts Prior To
Mating ???? ???? ??
23
Feeding Gilts Prior to Mating??????????

• The objective of the feeding program immediately
  before mating is to maximize the number of eggs
  ovulated.
• ???????????????????????
• Ovulation rate is the principle factor limiting
  litter size in gilts and increasing the level of
  feed intake prior to mating will significantly
  increase ovulation rate.
• ???????????????,?????????????????????
• Ovulation rate increases by 1-2 ova in response
  to increased feed intake during the 14-day period
  immediately prior to ovulation. This is the well
  know flushing effect.
• ????14????????,????????1-2?,??????????(????????
  ???????,?????)

24

• Flushing has been shown to increase plasma levels
  of FSH and increase the pulse frequency of LH
  suggesting that flushing enhances ovulation rate
  by stimulating the secretion of gondotrophins.
  ??????????????????????????????,???????????????????
  ????????
• The increase in gonadotrophin secretion is
  thought to be mediated through plasma levels of
  insulin and insulin-like growth factor-1 (IGF-1).
  ??????????????????????????????-1 (IGF-1)????????
• The increase in ovulation rate likely occurs
  either as result of increased follicle
  recruitment or a reduction in atresia.
  ???????????????????????????????

25
The Effects of Feed Level During the First
Estrous Cycle on Litter Size ?????????????????
Should feed intake be restricted for any reason
during the rearing period, special precautions
should be taken to ensure that gilts are fed ad
lib (at least 3 kg/day) for the two week period
prior to mating. ???????????????,??????2????????
??????????(??3??/?)?
26
Summary of Feeding Replacement Gilts????????

• Feed replacement gilts a specialized developer
  diet rather than a finisher diet to enhance body
  stores of vitamins and minerals.
  ??????????????????????,?????????????????????
• Feed diet containing 3000-3200 kcal DE and
  0.7-0.8 lysine ad libitum to ensure adequate
  reserves of fat and lean at mating.
  ????3000-3200??/??????0.7-0.8????????,???????????
  ??????
• For some genotypes, it may be necessary to
  restrict feed intake to reduce feet and leg
  problems associated with females getting too
  heavy or fat. ?????????????,?????????????????
• If for any reason feed intake is restricted, feed
  gilts ad libitum (gt3.0 kg) for two week period
  prior to mating. ???????????????,??????2??????????
  ?(??3??/?)?

27
Feeding Sows in Gestation ???????
28
Objectives of Feeding Program in
Gestation ???????????
29

• Minimize embryo mortality ???????
• Provide nutrients for fetal growth ????????
• Provide nutrients for the growth of the uterus
  and mammary glands ?????????????
• Allow for maternal growth ???????
• Replenish body reserves depleted during the
  previous lactation ???????????????
• Set the sow up metabolically for the ensuing
  lactation???????????????????

30
Goal is to have the sow produce a large, healthy
litter with a high probability of survival and
with the potential for rapid and efficient
growth. ????????????????????????????????
31
Approaches to Gestation Feeding?????????

• North American System ???
• Danish System ???

32
Feeding Pattern During Gestation(North American
System)????????(???)
33
North American System????

• In this system , there are three major phases
  where feed intake is adjusted . They are
  
  ???????????????,???
• Early gestation where the focus is on embryo
  survival (first two weeks) ???????????(0-2?)
• Mid-gestation where the focus is on sow body
  condition (days 14 to 100) ??????????(14-100?)
• Late gestation where the focus is on fetal growth
  and setting the sow up for the ensuing lactation
  (last 2 weeks)?????????????????,?????????(????)?

34
Feeding During Early Pregnancy (North American
System) ???????(???)
35

• Approximately 20-30 of all embryos die during
  the first 30 days of gestation.
• ??????30???20-30??????
• Research has shown that high levels of feed
  intake following mating are associated with an
  increase in embryo mortality.
• ?????????????
  ???????????

36

• The principle mechanism controlling the
  development of embryos and their subsequent
  survival is the secretion of uterine specific
  proteins.
• ??????????????????????????
• These proteins are stimulated by ovarian steroid
  hormones particularly progesterone. A rise in
  progesterone early in pregnancy enhances the
  uterine environment and makes it more supportive
  of the embryo.
• ???????????????????????????????????????,?????????
  ???
• Increased feed intakes have been shown to be
  associated with a decrease in plasma progesterone
  as a result of increased metabolic clearance of
  progesterone leading to a subsequent reduction in
  embryo survival.
• ??????????????????????????,???????????

37
Effect of Feed Level in Early Gestation on Plasma
Progesterone Levels and Embryo Survival
????????????????????????
Feeding Level Ovulation Total Embryo Prog
esterone Day 1-3 Day 3-15 Rate
Embryos Survival () (ng/ml) 1-3????
3-15???? ??? ???
????? ????? 1.9 kg 1.9
kg 14.5 12.4 85.9 10.5 2.5 kg 1.9
kg 14.9 11.5 77.3 3.7 2.6 kg 2.6
kg 14.9 10.2 66.9 4.5 _______________________
_________________________________ Jindal et al.,
1996
38
High-plane Feeding ??????
Increased hepatic blood flow ????????
Increased metabolic clearance rate
of Progesterone ???????????
Decreased plasma progesterone Concentration ?????
????
Suboptimal secretion of uterine
specific proteins??????????
Decreased embryo survival rate ???????
39
As a result of this research, it is generally
recommended that low (1.8-2.0 kg) level feeding
be conducted for the first two weeks of
gestation. ??????,???????????????(1.8-2.0??) ?
40
Feeding During Mid-Pregnancy (North American
System) ??????? (????)
41
The underlying objective of feeding sows during
mid-gestation is to allow for a moderate weight
gain and to achieve a target level of body fat at
farrowing (18-22 mm). ???????????????????????????
??????(18-22mm)
42
Target Feed Intakes for Gestating Gilts (Days 14
to 100)14 -- 100???????????
Breeding Back Fat at Breeding (mm) ??????? Wt
(kg) 8 9 10 11 12 13 14 15 16 17 18 19 20 115-11
9 2.6 2.5 2.4 2.3 2.2 2.1 2.0 1.9 1.8 1.7 1.7 1.7
1.7 120-124 2.6 2.5 2.4 2.3 2.3 2.2 2.1 2.0 1..9 1
.8 1.7 1.7 1.7 125-129 2.7 2.6 2.5 2.4 2.3 2.2 2.1
2.0 1.9 1.8 1.7 1.7 1.7 130-134 2.7 2.6 2.5 2.4 2
.3 2.2 2.1 2.0 1.9 1.9 1.8 1.7 1.7 135-139 2.7 2.6
2.5 2.4 2.4 2.3 2.2 2.1 2.0 1.9 1.8 1.7 1.7 140-1
44 2.8 2.7 2.6 2.5 2.4 2.3 2.2 2.1 2.0 1.9 1.8 1.7
1.7 145-149 2.8 2.7 2.6 2.5 2.4 2.3 2.2 2.1 2.0 2
.0 1.8 1.8 1.7 150-154 2.8 2.7 2.6 2.6 2.5 2.4 2.3
2.2 2.1 2.0 1.9 1.8 1.8 155-159 2.9 2.8 2.7 2.6 2
.5 2.4 2.3 2.2 2.1 2.0 1.9 1.8 1.8 160-164 2.9 2.8
2.7 2.6 2.5 2.4 2.3 2.2 2.2 2.1 1.9 1.9 1.8 165-1
69 2.9 2.8 2.8 2.7 2.6 2.5 2.4 2.3 2.2 2.1 2.0 1.9
1.9 170-174 3.0 2.9 2.8 2.7 2.6 2.5 2.4 2.3 2.2 2
.1 2.0 1.9 1.9 175-179 3.0 2.9 2.8 2.7 2.6 2.5 2.4
2.4 2.3 2.2 2.0 2.0 1.9 180-184 3.0 2.9 2.9 2.8 2
.7 2.6 2.5 2.4 2.3 2.2 2.1 2.0 2.0 185-189 3.1 3.0
2.9 2.8 2.7 2.6 2.5 2.4 2.3 2.2 2.1 2.0 2.0 190-1
94 3.1 3.0 2.9 2.8 2.7 2.6 2.5 2.5 2.4 2.3 2.2 2.1
2.1 195-199 3.1 3.1 3.0 2.9 2.8 2.7 2.6 2.5 2.4 2
.3 2.2 2.1 2.1 200-204 3.2 3.1 3.0 2.9 2.8 2.7 2.6
2.5 2.4 2.3 2.2 2.1 2.1 205-209 3.2 3.1 3.0 2.9 2
.8 2.7 2.7 2.6 2.5 2.4 2.3 2.2 2.2
43
Feeding Sows in Late Gestation ?????????
44

• The nutrient requirements of gestating sows are
  greatest in late gestation when fetal growth is
  at its peak. ??????????????????????????
• If feed intake is not increased during this
  period, the sow will lose back fat during the
  last two weeks of gestation. ????????????,??????
  ????????????
• In addition, there is evidence that this
  catabolic state will contribute to sows gorging
  and then going off feed in early lactation.
  ??,??????????????????,????????????
• Sows should receive an additional 1.5 kg of feed
  per day on top of their normal daily allowance
  from day 100 to 112 of gestation.
  ????100-112??????????????1.5?????

45
Performance of Sows Fed at Normal or High Levels
in Late Gestation (day 100-114)??????????????????
???
Feed Intake (kg/day) 2.3 3.9 Lactation Intake
(kg/day) ?????? 6.61 6.67 Piglet Growth (g/day)
????? 237 240 Wean to Estrus Interval (days)
6.2 5.4 ?????????? Subsequent Litter Size
?? 12.0 12.4 _____________________________________
____________Miller et al., (1996)
46

• On some farms, continuing to feed the additional
  1.5 kg of feed all of the way to farrowing can
  cause udder problems such as agalactia and
  mastitis. ?????,?????????1.5???????????,?????????
  
• In addition, feed intake may be reduced in early
  lactation. ??,???????????
• If this proves to be the case, then the
  additional feed should be discontinued
  approximately 2 days before the expected due date
  of the sow. ?????????,?????????2????????

47
Feeding Pattern in Gestation(Danish
System)?????????(???)

• Early gestation (days 0 to 28) provide sows with
  high levels of feed (gt3.0 kg/day).
  ????0-28?????????(gt3.0 kg/day)?
• Mid gestation (days 28 to 90), feed 1.8 to 2.4 kg
  of feed, depending on sow condition
  ????28-90???????,????1.8-2.4 kg?
• Late gestation (days 90 to 110), feed 3.0-3.5 kg
  of feed/day ????90-110?,????3.0-3.5 kg?

48
Comparison of Systems?????????

• The total feed provided to sows in gestation is
  approximately the same in the two systems.
  ?????????????????????
• However, the pattern of intakes differs
  dramatically, with the two systems being
  completely contradictory in recommendations
  during early and mid gestation.
  ??,????????????,???????????????????
• Under North American conditions and using
  traditional genotypes, high feed intakes in early
  gestation have been shown to be detrimental to
  reproductive performance. ?????????????,??????????
  ?????????????????

49
Effect of Feed Intake in Early Gestation (day
0-25) on Sow Reproductive Performance???????????
???????
High ? Low ? (3.5 kg) (1.5 kg) Weight change
early gestation (kg) ????????? 11.60 0.57 Backfat
change early gestation (mm) ?????????
1.87 0.76 Litter size ???? 10.95 12.05 ___________
______________________________________ Prime et
al., 1988. Animal Production 46 499
50
Comparison of Systems?????????

• Danish producers using the Danish system are
  achieving very high levels of productivity (gt30
  pigs/sow/year). ???????????????????(gt30
  ???/??/?)?
• However, it is not known whether or not the
  system can be applied to North American
  genotypes. ??,???????????????????
• Research should be conducted to determine the
  productivity of the system under North American
  conditions using different genotypes.
  ????????????????????,???????????????

51
Feeding in Gestation???????

• Regardless of the system used, the principle goal
  of the feeding program during gestation is to try
  to keep the sows in the breeding herd fit not
  fat. ???????,???????????????????????????
• Clearly both under conditioning and over
  conditioning are detrimental to the future
  reproductive performance. ???,???????????????????
  ????

52
Consequences of Thin Sows?????????

• Failure to recycle after weaning ????????
• Lower subsequent conception rates and litter size
• ????????????
• Increased susceptibility to bone fractures
• ????????
• Premature culling ????

53
Consequences of Fat Sows?????????

• increased farrowing difficulty ??????
• increased incidence of crushed piglets
• ???????????
• decreased lactation feed intake ????????
• lower milk production ?????
• increased susceptibility to heat stress
• ???????????

54
Methods to Assess Adequacy of Gestation Feeding
Program?????????????????

• Weigh Sows (target 45-60 kg gain)
• ????(??45-60??)
• Condition Score (target for score of 3)
• ????(??3?)
• Measure Backfat (target 18-22 mm)
• ????(??18-22 mm)

55
Effect of Sow Body Condition on Reproductive
Performance ????????????
Farm ???? Sows in Correct Body Condition ??????? Sow Mortality ??? Pigs Weaned/Sow/Year ????/?/??
1 59.3 13.4 20.6
2 61.7 17.7 19.7
3 75.2 5.7 21.1
4 78.8 8.7 22.8
5 79.1 8.4 23.5
6 79.3 6.5 22.2
7 84.3 7.8 24.6
1Sows with more sows in correct body condition
had lower mortality (r2-0.83) and weaned more
pigs (r2-0.88) 2Scharlach, 2005
?????????,???????,?????????
56
Feeding Sows During Lactation ???????
57
Objectives of Feeding the Sow During
Lactation?????????
Stimulate Milk Flow ????? Maintain Body Condition
of the Sow ?????? Prepare Sow for
Rebreeding ????????
58
The Effect of Feed Intake During Lactation on
Reproductive Performance???????????????
_________Daily Lactation Feed Intake
(kg)_????_______ 1.5 2.2 2.9 3.6
4.3 5.0 Lactation Weight Loss (kg)
44.5 30.8 27.4 19.6 15.8 9.0 ???? Backfat
Loss During Lactation (mm) 8.9 7.1 6.4
5.7 4.2 4.0 ???????? Weaning to Conception
Interval (day) 29.8 32.4 23.6 16.4 15.5
11.4 ?????????? Number of Eggs Ovulated 12.2
13.3 10.9 13.3 11.7 12.0 ??? Sows in Estrus
8 Days After Weaning 8.3 33.3 50.0
58.3 58.3 83.3 ???8???????? _____________________
__________________________________________________
______ King and Dunkin, 1986, Anim. Prod. 17
65-75
59
Feeding Sows in Lactation???????

• With proper management, modern sows have the
  capacity to consistently produce litters with
  12-13 piglets and subsequently generate
  sufficient milk to support litter weight gains in
  excess of 3 kg a day. ??????,???????????????12
  -13?,???????,???????????3???
• However, this must be accomplished without
  compromising the sows ability to be re-bred
  shortly after weaning or affecting the size of
  the subsequent litter ??,?????????????????????????
  ??????????

60
Every effort should be made to stimulate the feed
intake of the sow during lactation ?????????????
61
Methods of Increasing Lactation Feed
Intake????????????
62
Ensure Proper Body Condition of Sows?????????

• Although it is generally believed that high feed
  intakes in gestation are associated with lower
  feed intakes in lactation and subsequent loss of
  condition, recent evidence suggests that it is
  not necessarily the high feeding level in
  gestation that produces the negative effects but
  rather the fatness of the sow at farrowing.
  ???????????????????????????????????,??????????????
  ????,????????????
• Depending on genotype and parity, lactation
  intake begins to decline when backfat levels
  exceed 22 mm. The effect is particularly severe
  when back fat levels reach 24-25 mm.
  ??????,??????22 mm???????????????????24-25
  mm?,???????

63

• The mechanism through which a high feed intake in
  gestation reduces feed intake in lactation
  appears to be mediated by factors that control
  hunger. ????????????????????,????????????????
• During lactation, insulin levels of sows fed
  lower amounts of feed in gestation are much
  higher than those of sows fed ad libitum.
  ?????,?????????????????????????????
• These high insulin levels may stimulate appetite
  during lactation by reducing lipid mobilization
  and increasing peripheral glucose use.
  ??????????????????????????????????????

64
Ensure Adequate Dietary Protein?????????

• The level of dietary protein has been shown to
  affect the amount of feed consumed during
  lactation. ???????????????????????
• Piglet weaning weights were also higher when the
  sow received higher levels of dietary protein.
  ????????????????????????
• The consumption of low protein diets during
  lactation can also cause excessive delays in
  estrus and poor conception rates after weaning,
  particularly if fed to first litter sows.
  ??????????,?????????????????????????????????
• Lactation diets should contain a minimum of 16
  crude protein (0.95 lysine). ????????16???( 0.95
  ???)

65
Effect of Protein Level During Lactation on Sow
Feed Intake and Body Condition???????????????????
??


Dietary Protein
Level () 12 14 16
18 ______________________ _
???????_____ Sow Feed Intake (kg/day) 3.5
4.6 5.5 5.8 ??? Sow Weight at Farrowing
(kg) 152.2 140.9 143.6 145.9 ????? Sow Weight at
Weaning (kg) 126.8 130.0 147.3 152.3 ???? Sow
Weight Change (kg) -25.4 -10.9 3.7
6.4 ?????? Piglet Weaning Weight (kg) 5.5
6.1 6.2 6.8 ????? Mahan and Grifo, 1975, J.
Anim. Sci. 41 1362-1367.
66
Increase Frequency of Feeding??????

• Sows will consume more feed if fed twice rather
  than once daily. Consumption is likely to
  increase further if they are fed even more
  frequently. ??????????????????????,????????
• In a study conducted by the NRC-89 Committee on
  Confinement Management of Swine, sows fed three
  times a day consumed a total of 108.4 kg of feed
  during lactation while those fed only once a day
  consumed 101.6 kg of feed. ?89?NRC?????????????,??
  ??????????108.4 kg??????????101.6 kg?
• In addition, weight loss during lactation was
  reduced for the group of sows fed three times a
  day (22.5 versus 28.5 kg of body weight lost).
  ??,?????????????????(??22.5?28.5 kg )?

67
Use Proper Particle Size (600-800
um)???????(600-800??)

• Particle size reduction increases the surface
  area of the grain, thus allowing for greater
  interaction with digestive enzymes and improving
  digestibility ????????????,????????????????????
• It also improves the ease of handling and mixing
  characteristics ???????????????
• However, excessive grinding will increase the
  energy costs of feed processing, cause dust
  problems and increase the incidence of gastric
  ulcers ??,???????????????????????????????
• Feed intakes are also reduced with excessive
  grinding ????????????

68
Effect of Particle Size on Lactation Performance
????????????
Particle Size (um) ???? Particle Size (um) ???? Particle Size (um) ???? Particle Size (um) ????
400 600 900 1200
Feed Intake (kg) ??? 4.43 4.40 4.24 4.19
Sow Weight Loss (kg) ?? 8.2 7.2 10.5 10.5
Backfat Loss (mm) ???? 2.9 3.0 3.3 3.0
Digestibility () ??? 88.3 86.4 85.1 84.2
Ulcer Score ???? 2.9 2.7 1.4 1.3
Goodband et al., 2005
69
Feed Pelleted Diets??????

• Use of a pelleted diet has been shown to increase
  sow feed intake during lactation.
  ??????????????????????
• Pelleted diets also tend to reduce the amount of
  feed wastage.?????????????
• However, since very few producers have the
  ability to pellet on the farm, the advantages of
  feeding a pelleted diet are only available to
  producers purchasing a commercially formulated
  lactation diet. ??,???????????,???????????????????
  ?????

70
Effect of Pelleted Diets on Lactation
Performance ????????????
Mash Pellets
??
??? Feed Intake ??? 6.00 6.22 Lactation Weight
Loss (kg) 7.36 6.95 ???? Fat Loss (mm)
???? 2.25 1.00 __________________________________
____________
Baudon and Hancock, 2003
71
Consider Wet Feeding????

• It has been well demonstrated that sows will
  consume more of a wet feed than they will of a
  dry one. ?????????????????
• Although it would be impractical for most
  producers to convert their operations to a wet
  feeding system, the simple act of mounting the
  water nipple in the farrowing crate directly over
  the feed hopper can help to stimulate sow feed
  intakes. ??????????????????????,??????????????????
  ????????????????
• Care should be taken to clean the feeder on a
  regular basis in order to prevent molds from
  developing on the wet feed. ???????????????????

72
Effect of Wet Feeding on Lactation Performance
??????????
Dry Feed Wet Feed

??
?? Sow Feed Intake (kg/day) ??? 4.7
5.3 Sow Energy Intake (MJ DE/day) 62.3
69.3 ????? Lactation Weight Loss (kg) 29.8
23.2 ???? ________________________________________
________________ O'Grady and Lynch, 1978, J.
Agric. Res. 17 1-6.
73
Increase Water Consumption????

• High water intakes are required to support the
  demands for milk production. ????????????????
• A lactating sow can consume as much as 30 litres
  of water per day. If the flow rate is 500
  mL/minute, then a sow will need to spend at least
  60 minutes a day drinking in order to meet her
  daily water requirements. ????????30??,????????500
  ??/??????????,?????????60???
• Particularly following a difficult delivery, some
  sows may be unwilling to stand for this amount of
  time and therefore water consumption will be
  reduced which will have a negative effect on
  lactation feed intake. ???????,???????????????????
  ???????????????

74

• Provision of a second water nipple that allows
  sows to drink while lying down has been shown to
  be beneficial particularly shortly after
  farrowing ?????????????,?????????,???????????????

75
Techniques to Increase Water Intake??????????

• A flow rate of at least 1.5 to 2.0 litres per
  minute has been shown to be beneficial in
  ensuring adequate water intake for sows.
  ???????????,??????????1.5-2.0??????? ?
• Check water lines frequently to ensure
  obstructions are not limiting water flow
  ??????,??????????
• Many producers find that filling the sows feed
  trough with water after feeding is a useful way
  of stimulating water intake. ?????????????????????
  ????????
• The depth of the water in the trough is very
  important as pigs are not designed to lick up
  water. For sows, a depth of 3.8 cm is
  recommended. ????????,?????????????????????3.8 cm?

76

• Although nipple and bite drinkers will eventually
  provide adequate water, some sows may become
  frustrated and stop drinking before sufficient
  water has been obtained. ????????????????,???????
  ???????????????????
• Research has shown that lactating sows receiving
  water from a trough located next to the feed
  hopper drank more water and wasted less,
  resulting in higher feed intakes and therefore
  weaning heavier pigs
• ????????????????,????????????,????????????????

77
Comparison of Water Consumption by Lactating
Sows Provided Water Via a Trough or a
Drinker???????????????????
Trough Drinker
??
??? Water Used
(L/day) ??? 23 18 Water Spillage ??? ND 3.6 Feed
Consumption (kg/day) ??? 6.61 6.04 Pig Weaning
Weight (kg) ???? 6.03 5.81 NDno detectable
wastage ????? Gadd, 1996
78
Reduce Farrowing Room Temperature???????

• The effective environmental temperature of the
  farrowing room is one of the most critical
  factors affecting feed intake in lactating sows
  and many producers maintain their farrowing room
  at too high a temperature. ??????????????????????,
  ??????????????
• Sows maintained at a lower temperature (gt20ºC)
  consume more feed, lose less weight and wean
  heavier piglets compared with those housed at the
  higher temperatures. ????????(lt 20ºC)
  ?????????????????????????

79
Effect of Environmental Temperature on Lactation
Performance??????????????
Temperature ?? 27oC
21oC Sow Feed Intake (kg/day) ??? 4.6
5.2 Sow Weight Loss (kg) 110 Days to
Weaning 21.0 14.0 110???????? Piglet Weight
at 28 Days (kg) 6.2 7.0 ??28????? Lynch,
1978.
80
Cooling Systems ????

• In order to stimulate feed intake, attempts
  should be made to cool down the farrowing room.
  ??????,?????????????
• If building a new barn, producers might consider
  the installation of snout coolers or drip
  cooling. ?????????,?????????????????????
• Snout coolers with an airspeed of 0.3 m/sec have
  been shown to increase feed intake by 250 g/day.
  ????????0.3?/???????????250?/??
• Drip coolers providing 2 litres per sow per hour
  (running for 3 minutes in a 10 minute cycle) have
  also been shown to be effective in increasing
  feed intake. ??????????????2??(?10???????3??)?????
  ??????

81
Effect of Cooling System on Lactation Performance
of Sows??????????????
Control Snout Cooler Drip Cooler Combined
??? ??????
????? ?????? Feed Intake
(kg/day) 4.0 4.86 5.38 5.86 ??? Weight Loss
(kg) 19.86 14.38 10.8 2.0 ????
McGlone et al., 1988
82
5
If the temperature of the farrowing room is to be
decreased, supplemental heat must be provided for
the baby pigs. Use heat lamps, covered creeps,
heat pads etc ??????????,???????????,?????????????
???????
83
Floor Type ????

• The farrowing floor surface influences heat loss
  and therefore could affect feed intake.
  ??????????????,??????????
• Sows housed on plastic-coated, expanded metal or
  woven wire floors consumed about 0.5 kg less than
  sows housed on highly conductive floor surfaces
  such as metal (i.e. Tri-bar) or concrete.
  ???????????????????????????????????????????0.5???

84
Ventilation and Insulation?????

• The maximum ventilation rate of the farrowing
  room should be checked to ensure adequate
  airflow. Although this may not necessarily cool
  the sows, fresh air is beneficial in stimulating
  appetite.
• ???????????????????????????,???????????????
• Providing the proper amount of insulation is
  useful in preventing increases in farrowing room
  temperature during hot days. The standard
  insulation specification for the roof is
  0.4W/m2/oC and for walls 0.5W/m2/oC.
• ?????????????????????????????????????0.4W/m2/oC,?
  ???????? 0.5W/m2/oC?

85
Diet Modification ????

• In situations where it is not possible to reduce
  the farrowing house temperature, consideration
  should be given to feeding diets with a reduced
  heat increment. ???????????????,???????????????
• Incorporating fat or oil as a partial substitute
  for carbohydrate will reduce the heat increment
  of the diet and thus allow sows to consume more
  energy in hot weather. ?????????????????????,???
  ???????????
• Reducing the protein level of the diet and using
  synthetic amino acids to provide the proper
  balance of amino acids can also achieve this
  purpose. ?????????????????????????????????
• Feeding during the cooler times of the day will
  also stimulate feed intake. ????????????????

86
Effect of Light ?????

• There is evidence to suggest that sows exposed to
  longer periods of lighting during the day may
  have higher feed intakes. ?????????????????????
• Increased weaning weights and higher milk yields
  which are commonly associated with increased feed
  intakes have been observed when sows were housed
  in farrowing rooms with 16 hours of light per day
  in comparison with 8 hours of light per day.
  ????????????16???8????,????????????????????????
• Improved rebreeding performance has also been
  reported. ??????????????????

87
Effect of Lighting Duration on Sow Lactation
Performance????????????????
8 hrs Light 16 hrs Light 16 hrs Dark 8 hrs
Dark
8h??16h??
16h??8h?? Pigs Born Alive ????? 11.6 12.1 Pigs
Weaned ???? 7.9 9.4 Survival Rate ()
??? 80.1 84.4 Milk Yield (kg) ??? 5.1 6.1 21
Day Litter Weaning Weight (kg) 28.4 42.9 21
????? Return to Estrus () ??? 77.8 100 Mabry et
al., 1982 (J. Anim. Sci. 57 292-295)
88
Ensure Provision of Palatable Diets???????????

• Choose palatable ingredients (corn, wheat,
  hulless barley, soybean meal, fat)
  ?????????(????????????????)
• Avoid the use of any ingredient of questionable
  palatability (rye, canola meal, lupins,
  fababeans) ????????????(????????????)
• Do not use moldy feed in lactation diets
  ??????????????
• Avoid excessive levels of dietary calcium (gt1.0)
  ?????????(gt 1.0)
• Avoid excessive grinding (target 600-800 um)
  ??????(??600-800??)

89
Use of Flavors ??????

• The use of flavors in animal feeds has increased
  considerably in the past decade as more attention
  is being paid to ingredient and diet
  palatability. ??????????????????,?????????????????
  
• Many experiments have been conducted using feed
  flavors in the hope of increasing the feed
  consumption of sows during lactation.
  ??????????????????????????
• The products used have ranged from simple spices
  and tonics to aroma modifiers, sweeteners, flavor
  intensifiers and artificial flavors as well as
  certain natural feed ingredients.
  ????????????????????????????????????????,?????????
  ??

90
Use of Flavors ??????

• Although some results indicate that flavor
  additives can be used to attract sows to their
  diet, increase feed intake and reduce sow weight
  loss during lactation, producers should be aware
  that very little is known on what specific
  flavors pigs find attractive. ???????????????????
  ??????????????????,???????????????????????????????
  ??
• Since flavours tend to be expensive feed
  ingredients, considerable caution should attend
  their use in sow diets. ?????????????,????????????
  ???????

91
Effect of Spray Dried Porcine Plasma on Lactation
Performance????????????????

Control ??? SDPP ??????
Feed Intake (kg/day) ??? 4.2 4.1
Lactation Loss (kg)???? 37.2 32.4
Backfat Loss (mm) ???? 2.4 2.7
Bertelsen et al., 2005
92
Methods of Increasing Lactation Feed
Intake????????????

• Avoid Over Conditioned Sows (gt25 mm) ??????
• Increase Dietary Protein Level (gt16)
• ????????(gt16)
• Increase Feeding Frequency (3x day) ??????
• Pellet Diet ??
• Wet Feed ??
• Ensure Adequate Water Intake ??????
• Reduce Farrowing Room Temperature (lt20 C)
• ????????(lt20 C)
• Maintaining Adequate Lighting (gt14 hours) ??
• ?????(gt14 ??)
• Choose Palatable Ingredients ?????????