Hog farms across the world, including those in the U.S., are getting dirtier. And there are three reasons why.

First, routine cleaning and disinfecting is just that - routine. Because it is a boring, repetitive task, familiarity can breed carelessness in the best workers and contempt in the worst. Some European surveys asked workers why they left pig production and "a boring, repetitive job" was high on the list.

One of the reasons why pig-affecting viruses seem to be on a roll could be that the modern strains of such pathogens just love a rushed cleaning job. And there lies the second reason - workers. They are eternally chasing their tails on repairs which need urgent attention, tend to hurry through the vital job of regular biosecurity. We overstock pigs and under stock our workforce.

Careful preparation is a critical part of disinfecting. The third reason why we are seeing more diseases these days is that farmers place too much reliance on disinfectants (see Table 4).

Where a detergent or sanitizer was used before disinfectant, pigs grew an ounce a day more, up to 88 lb. This resulted in $2.43 more meat/pig.

Of the last 12 farms I've visited, only five were using a detergent in the pressure-washing process.

Precleaning is especially important with all-in, all-out (AIAO) (see Table 3). Economics

Some 1.4 ounces/day improved gain from 13 to 200 lb. results in an improvement in saleable meat/ton of feed used of 53 lbs. This is equal to a 15% reduction in cost of feed/ton at $33/pig. The extra cost of cleaning and the special biocide detergent used is equal to 5% of the cost of one ton of feed. Therefore, a payback or return to extra outlay (REO) of 3:1 is achieved, just from correct precleaning alone.

The benefits of using a detergent are shown in Table 2, where bacterial counts are shown at various stages of cleaning.

Washing with water reduces bacterial contamination up to 60% - well above the before-disinfection target level. When adding a good heavy-duty detergent, the contamination is reduced even more - to well below the target level. You can be left with 4,000 times more bacteria for the disinfectant to deal with if you don't use a detergent. A reduction in microorganisms to 0.001% of their initial value by the end of disinfection is the goal.

Ten points to consider when choosing a detergent: 1. It must be farm-specific. Industrial detergents may be insufficient to cope with the semi-porous surfaces (plastic, metal and worn concrete floors) you have to work with. Check that the detergent is specifically designed for farm use.

2. It should have good degreasing activity. Fat and grease protect microorganisms by long-chain fat molecules. Some manufacturers have special defatting detergents.

3. Is the detergent safe to both humans and pigs? Some powerful industrial detergents, while safe to machinery, are questionable for livestock.

4. Use it exactly to the manufacturer's instructions. Read the label. Then consider the circumstances of use. Are you using estimated dilution rates, or just roughly calculated and measured, or measured and calculated every time? Do a check-up audit periodically.

5. Does it interfere with the subsequent disinfectant's activity? Check this with the manufacturer if using a different firm for the latter.

6. Can it be applied through your existing equipment with minimal modification? Ask the manufacturer before choosing.

7. Does it leave residues? Residues can make the floor slippery and harbor microorganisms. Cumulative residues can be especially dangerous.

8. It should be alkaline. This helps dissolve fats and protein in built-up manure deposits.

9. It should work in hard water conditions.

10. Foaming can help. Foaming increases contact time and allows workers to see where the detergent has been applied. It also decreases the amount of water needed in presoaking and pressure washing.

Less water means lower operating costs and fewer washings going into any slurry to be removed.

Table 1 shows the value of an improved cleaning program. The economics show an improvement in saleable meat/ton of feed of 57 lb., equal to a 19% reduction in feed cost savings, yielding an REO of 3.8:1 after allowing for extra cleaning costs.