This week I got a plaintive, if not desperate, phone call from a 5,000-sow operation manager in the U.S.

His problem was the litter average in his unit was just a little over nine born. But despite this modest output, his sows were wasting away to skin-and-bones.

And management seemed reluctant to increase the feed allowance or improve the nutrient specifications, even though they had invested in a modern genetic line with a high appetite.

Six years ago, the mixed genotypes of that time averaged 21.9 pigs weaned/year (weaning at 23 days of age), on 1.27 tonnes (2,822 lb./tonne) of feed. This yielded 280 lb. weaner weight/sow/year.

Some of today's producers with modern genetic lines weaned over 25.6 pigs/sow/year (22 days at weaning) on 1.28 tonnes of feed/year. This yielded just under 400 lb. of weaner weight/sow/year. That's a 42% increase in productivity.

This provides some important lessons for his employers:

1. Modern genotypes have the ability to produce 40% or more weaner output for the same amount of feed consumed 10 or more years ago (see Table 1).

2. Therefore, if the same amount of feed is fed/sow/year, the sow must have a higher nutrient-dense diet, otherwise performances will drop (ac- counting for the nine born).

3. Diets must be fed in a much more precise manner, with certain diets offered certain times.

4. It will cost about 18% more each year to feed that way, but so what. Feed costs - about 60% of total costs - increase by 18%, an 11% increase in total costs, but income rises by 42%, giving a 3.8:1 return on extra outlay (REO).

Feeding Right From The Start Correct sow nutrition de- pends, first of all, on setting up the replacement gilt correctly. Like it or not (and some academics don't), we firmly believe in Europe that modern lean-gain gilts should be mated much later and at heavier weights. Not doing this jeopardizes the chance of 25 weaners/sow/year.

For example, gilts are first mated during their third estrus when they are about 210-230 days old, weighing 298-320 lb. and with about 3/4-in backfat at P2 (Parity 2).

Not following this procedure jeopardizes long-term productivity. Poor sow condition causes premature culling, lowers the herd's immune status and this susceptibility leads to more disease.

To combat diseases, a 6-week (preferably 8-week) acclimation period is needed after first entry into the herd. If bought-in at 220 lb. with P2 fat not less than 1/2 in., during the acclimation period, the replacement gilt should gain about 77 lb. and P2 backfat increase by 1/4 in.

To achieve this, feed 9,082 kilocals digestible energy (DE)/day and 16 grams/day total lysine. At a daily intake of 6.5 lb./day this suggests a diet of 1,397 kilocals/lb. and 6 grams total lysine, supported by the usual amino acid profile.

And gilts should be flushed two weeks before the third estrus.

After First Service During pregnancy, all sows can be fed basically the same, but daily allowances depend on age, body condition and size, along with environmental differences.

Today's young sows, which are well below their mature body weight, have a high potential for lean growth. Although this increases the requirement for protein and energy intake, current advice is to limit lean growth in early life and during consecutive pregnancies. This ensures their potential for production and tissue repair is satisfied while minimizing their needs for maintenance, especially later in life. This can be achieved by restricting the intake of lysine (ideal protein) during the first pregnancy (see Table 2).

The values are based on model predictions, assuming minimum backfat thickness of 5/8 in. at mating and 3/4 in. at farrowing and 11 pigs born/litter.

Currently, on many units in Europe, the feeding strategy advised for all dry sows is to standardize the intake of lysine to 12.4 grams/day (5 lb. of feed/day, 0.55% lysine) for all genotypes. This aims to bring down lean tissue growth rate to a level which is below the potential for most genotypes - a potential which is not required in the female. Recently, energy intake has been increased from 7,100 to 7,290 kilocals DE/day with the aim of further defending fat reserves and enhancing fetal growth. Preliminary results have shown an improvement in piglet birth weight.

Lactating Sows We now should have a sow at farrowing with a condition score of 3.5 and a P2 backfat between 0.94 and 1.10 in. would be bordering on condition score of 4.

The secret of lactation feeding is to minimize fat and muscle loss during lactation. The key to this is appetite.

Figure 1 gives a typical target energy intake to minimize condition loss and sustain litters of various sizes and weaning weights.

Based on model predictions and assuming sow weight at farrowing of 350 lb., piglet birth weight averages 2.9 lb. and weaning at 24 days.

In Europe, the key to satisfactory intake is the use of a standardized feeding scale during lactation. All sows are fed to a standard scale in the first 10 days after farrowing. This allows 5.5 lb. of feed on day 1, increasing by 1.1 lb./day to achieve an allowance of 15.5 lb. on day 10. Thereafter, sows are treated as individuals by placing them on a daily feed allowance based on litter size and piglet growth rate, called the "Stotfold Scale."

For anything, but exceptionally lean genotypes, you will find 1,572 kilocals/DE kg. and 1% total lysine, and 0.8% oil fed at the scale above (and after 7 days, to the Stotfold Scale) will be excellent for modern genotypes, and sows will only lose 10-20 lb. and 0.07-0.15 in. P2 backfat if at all, assuming the correct environmental conditions are provided, of course.

Weaning To Rebreeding Latest advice is to provide a diet with 1,604 kilocals DE/lb. and 1.3% lysine, and 5% oil. Sows are offered 11-13 lb./day. This generous intake helps them switch from a catabolic (tissue-mobilization) state to an anabolic (tissue-building) state to get the right hormones in place in the 4 to 5 days available.

Overall It is essential to feed the whole sequence, and check carefully that your feed supplier is meeting these nutrient specifications. They may seem unnecessarily high to an American feed mill, but insist that they meet them.

It will cost more, but remember, you should increase your output by 40%, and that covers a price increase per ton, with a lot to spare.

I realize that some of the criteria - the long wait to first service, the special gilt developer diet, the high lactation dietary specifications, three diets, etc., - could seem strange and over-fussy to traditional American producers. They are definitely not. We find them essential for lean, fast growing and big sows with large litter potential. Correct nutrition will let them express it.

After all, many are achieving 25 pigs/sow/year quite easily, but we would never do it without these sort of increased nutrient specifications.