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Distiller’s Dried Grains with Solubles, Housing and Breeding Herd Performance

09 September 2014

Michigan Pork Quarterly

In 'MSU Pork Quarterly', Dale Rozeboom (Extension Specialist at Michigan State University) and Thomas Guthrie (Extension Educator of Jackson, Michigan) review a recent experiment at the University of Minnesota, which found that long-term feeding of distillers dried grains with solubles (DDGS) to sows is linked to smaller litter size but does not affect sow longevity. Compared to stalls, group-housing decreased both litter size and sow longevity.


The major goal for the breeding herd is to provide excellent nutrition and housing in order to maximise productivity and longevity.

DDGS have been commonly fed to growing swine for decades but have been used cautiously in sow diets. There is limited research documentation in regard to the use of DDGS in sow diets.

The housing of gestating sows is an important issue for pork producers in Michigan and throughout the United States.

Previous research has shown that housing sows in groups during gestation may or may not have negative effects on reproductive performance. Inconsistency among studies indicates that there are numerous aspects of housing systems that can and do influence breeding herd performance.

A recent research report from the University of Minnesota (Li et al., 2014) has described interesting information about the interactive effects of feeding DDGS-containing diets and housing system on sow performance and longevity over three reproductive cycles. In this review, its authors outline the highlights of that study.


The study began at breeding, when a total of 401 females (311 gilts and 90 first-parity sows) were assigned randomly within parity to one of four treatments. Sows were then kept on the same treatments for up to three reproductive cycles.

Experimental treatments were:

  1. Sows fed a corn-soybean meal based diet throughout gestation and lactation and housed in pens throughout gestation.
  2. Sows fed a corn-soybean meal based diet throughout gestation and lactation and housed in individual stalls throughout gestation.
  3. Sows fed a similar corn-soybean meal based diet with the inclusion of 40 per cent DDGS in the gestation diet and a 20 per cent DDGS inclusion rate in the lactation diet and housed in pens throughout gestation.
  4. Sows fed a similar corn-soybean meal based diet with the inclusion of 40 per cent DDGS in the gestation diet and a 20 per cent DDGS inclusion rate in the lactation diet and housed in individual stalls throughout gestation.

Sows remained in their gestation housing system until 109 days of gestation. Electronic sow feeders were used for sows housed in pens (about 50 sows per pen; space allowance of about 24 square feet per sow) and managed in dynamic groups. Sows housed in pens were exposed to two mixing events during gestation: at introduction to the pen and then again eight weeks later when new sows were introduced. Individual stalls were equipped with a feeder and nipple drinker and sows were fed once a day. For all females, the amount of feed received in gestation was adjusted to achieve a body condition score of ‘3’ at the time of farrowing.

In lactation, all sows were housed in individual farrowing stalls, stair-stepped increasing amounts of feed for five days post-farrowing, and allowed ad libitum access to their assigned lactation diets thereafter; until weaning which occurred at about day 19 of lactation. Within 24 hours of birth, piglets in litters from the same dietary and housing treatment groups were cross-fostered to equalize litter sizes as much as possible.

Concentrations of vomitoxin and zearalenone in the two DDGS diets used in this experiment were <0.66mg/kg and <0.2 mg/kg, respectively, in the first lot and <0.5mg/kg and <0.2mg/kg, respectively, in the second lot. The authors described these concentrations as “generally recognised as safe for swine diets".

Longevity was studied over three reproductive cycles and sows were removed from the study for the following reasons: if they failed to conceive after the second post-weaning service, were anoestrous longer than 21 days post-weaning, experienced lameness (attempted to relieve limbs or reluctant to put weight on limbs), or death.

Sow genotype was described as English Belle (GAP Genetics, Winnipeg, Manitoba) and all litters were produced by artificial insemination using Duroc boar semen.


Litter size

Sows fed DDGS diets had smaller litter size born alive (11.0 versus 11.6) and at weaning (9.8 versus 10.2) than sows fed the corn–soybean meal diets.

Feeding of DDGS resulted in more stillbirths (0.9 versus 0.7).

The researchers from Minnesota admit that a definitive explanation for the increase in stillborn pigs as a result of feeding diets containing DDGS is not clear. But they speculate that DDGS may contain peroxidised oil which creates an oxidative stress for sows in late gestation that leads to an inefficiency of nutrient and oxygen transfer through the placenta causing death of foetuses before birth.

Over three reproductive cycles, sows fed DDGS produced fewer live-born pigs (26.2 versus 27.4) and tended to have fewer pigs weaned (23.7 versus 24.5) than sows fed corn–soybean meal diets. Pre-weaning mortality did not differ between dietary treatments.

Group-housed sows tended to farrow smaller litters born alive (11.0 versus 11.5), and statistically had significantly fewer pigs at weaning (9.9 versus 10.2) than stall-housed sows.

The researchers describe the 0.5 fewer piglets born alive to group-housed sows, a “major finding” of their study.

In the discussion of this result, they state that there is inconsistency among studies regarding the impact of sow gestating housing on number born alive. They cite two studies that agree with their findings and three studies that showed no impact of group housing on this important measure.

They concluded “Numerous aspects of housing systems can and do influence prolificacy of sows.”

Stillbirths per litter were unaffected by housing treatment. Over three parities, stall-housed sows farrowed more total pigs (30.1 versus 26.7) and live pigs (28.4 versus 25.2), and weaned more pigs (25.2 versus 23.1) compared with group-housed sows.

Pre-weaning mortality did not differ between housing treatments.

Without a clear explanation of reasons why such would happen, the Minnesota research group noted that the reduction in litter size in group gestation housing compared with stall housing was greater when sows consumed corn-soybean meal diets. Sows fed DDGS produced a similar number of pigs in stall and group pen housing. Possibly, since the litter size born alive of the DDGS sows is already 0.6 pigs less, the likelihood of the housing system having an additional measurable reduction is more improbable.


Overall, diet did not affect the percentage of sows that were able to complete three reproductive cycles. A greater number of sows fed DDGS diets than those fed the corn-soybean meal diets were culled because they were anoestrous longer than 21 days post-weaning (52 versus 41).

In contrast, a greater number of corn-soybean meal-fed sows than DDGS-fed animals were culled because they failed to conceive after the second post-weaning service (21 versus 16).

Housing gestating sows in pens in this study resulted in fewer sows completing three reproductive cycles than housing in stalls (68.9 versus 55.8 per cent).

Compared with individual stalls, group housing resulted in more sows (51 versus 42) that were anoestrous longer than 21 days post-weaning, more sows that failed to conceive (24 versus 13) after the second post-weaning service and a greater incidence of culling due to lameness (11 versus 5).

The Minnesota research group mentions four other research studies in which group gestation housing has negatively affected sow longevity, mostly due to an increase in lameness. They did not cite any other studies that have documented reproductive failure in group-housed sows.

Further Observation

Litter growth

The authors reported and discussed differences in litter weight gain due both to diet and housing system. Differences were likely due to the differences in litter size.

When number of pigs weaned was used to ‘adjust’ litter weight gain, neither sow diet nor sow gestation housing affected piglet growth rate during lactation. The adjustment is correct, as lactating sows respond to the ‘demand’ for milk and this demand reflects the size of the nursing litter.

Lactation feed intake

Average daily feed intake (ADFI) of sows during lactation was not different between sows fed DDGS and corn-soybean meal diets during any reproductive cycle.

Lactation feed intake was different between housing systems across reproductive cycles. Sows housed in stalls consumed 0.66 lb. less feed each day in the first reproduction cycle.

Housing system did not affect ADFI during lactation in the second reproductive cycle but in the third reproductive cycle, stall-housed sows consumed 0.66 lb. more feed each day than the group-housed sows.

Sow body condition

No differences in sow gestation weight or backfat change were observed. However, feed intakes in gestation were not reported, making it difficult for the authors to separate out potential effects of dietary or housing treatments on sow weight and backfat changes.

Take Home Messages

This study suggests that long-term feeding of DDGS decreases litter size but does not affect sow longevity.

It suggests that long-term housing of sows in pens decreases litter size and sow longevity.

Peculiarly, this study suggests that sow diets and housing well-being may interact to affect lifetime productivity. Diets and housing are important but research reports like this one frequently do not clearly describe in detail other important aspects of husbandry or stockmanship.

Sow well-being, productivity and longevity are assuredly also outcomes of management and the implementation of critical animal care practices.


Li, X., S. K. Baidoo, Y. Z. Li, G. C. Shurson and L. J. Johnston. 2014. Interactive effects of distillers dried grains with solubles and housing system on reproductive performance and longevity of sows over three reproductive cycles. J. Anim. Sci. 92:1562- 1573.

September 2014

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