The need for a consistent and high level of feed intake during lactation has been emphasized almost incessantly by veterinarians, nutritionists and reproductive physiologists. The mechanisms are complicated, but the outcome is one or a combination of increased weaning to service intervals, lowered farrowing rates, lowered litter sizes, and increased culling and mortality rates.

Have we improved a great deal in this area with the emphasis placed on it? In many cases it has been difficult to measure and more difficult to change in our production systems. In some cases we have compensated for low feed intake levels by using compounds such as antibiotics, chromium or beta carotene. In other cases we have simply compensated for poor reproductive performance by increasing the sow herd. In many cases we must reexamine our efforts and try again to improve the level of lactational feed intake.

The first challenge is to measure the level of feed intake. In many of our herds it is much more complex than simply measuring the level of lactation diet delivered and dividing it by the number of days that sows are in the crates. Sow feed intake is, in many herds, an 80/20 problem: 80% of the problem occurs in 20% of the sows.

In these herds the average does not count as much as the number of days that sows eat an inadequate amount during lactation. These are the herds where the average condition is not bad at weaning, but there are some very thin sows. Sow condition can be another indirect measurement of lactational feed intake. Some herds do restrict overall intake in the farrowing house by limit feeding. In these herds the average intake does stand out and these herds usually have quite high culling rates.

When lactational feed intake is viewed in this manner, the level of problems in herds are often highlighted. Average lactational feed intakes can range from seven to 17 lbs per sow per day. The proportion of days that a sow eats less than 8 lbs of feed from day two until weaning can range from five to 60%.

Once we have the problem identified, the possible causes are numerous, but here are a few:

This is a phrase coined by Dr. Guy-Pierre Martineau of the University of Montreal and it aptly describes the problem. A sow is over conditioned at farrowing, goes off feed due to ketosis and/or secondary infections, often due to a difficult farrowing. It never really does come back on feed and piglets do poorly and the sow is thin at weaning. In pen gestation situations it can do quite well if it becomes pregnant and thus be over conditioned at the next farrowing.

The argument is that the sow condition is actually difficult to measure accurately. It is difficult and dangerous to compensate for a low lactational feed intake by putting on extra condition in gestation. This is a case where the upside of over conditioning is worse than the downside of under conditioning. Thus the average should not be the perfect sow but a moderately under conditioned sow if condition measurement is inaccurate.

The Dry Sow Syndrome

For a sow to eat a sow has to drink. A lactating sow has to drink a great deal to wet down the feed, to excrete the wastes of this increased metabolism, to produce milk, to prevent constipation, and to compensate for fluids lost during farrowing. It is not surprising, then, that many sows are moderately dehydrated during lactation. This in turn limits feed intake.

Water nipple designs are being reexamined and improvements have been seen in many herds where flow rates have been increased, especially where there has not been a concomitant increase in pressure. Water requirements can also be kept under control by keeping temperatures down during farrowing and ensure that the feed ingredients do not have to be excreted in high amounts.

The Low Preweaning Mortality Syndrome

Working in the farrowing house provides the competing requirements of meting the needs of the piglets and their dam. Not only is the sow providing nutrients for the piglets, it is also being prepared for mating. The farrowing room temperature and the time of the farrowing manager must be balanced to provide care for both parties.

Too often the care is biased toward the care of the piglets. The best temperature for a lactating sow is in the region of 55 to 65 F. Anything more is for the sake of the litter. Efforts to provide microenvonments for the piglets are often useful.

Feeding correctly also takes a great deal of labor that may not result in any change in the quality of weaned piglets. It involves feed delivery at proper and scheduled intervals. It is best performed when intakes are recorded and subsequent feeding corresponds with recorded levels. It involves keeping feeders clean and ensuring that nipples flow at the correct rates. It involves monitoring the health of the sows as closely as the progeny. It is then that we can have a balance in the farrowing house

Take-Home Message