Treatment and Advice

The treatments used throughout the course of the problem are summarized in Table 1. In-feed antibiotic medication (Chlortetracycline 400ppm) was initiated forthwith since this was already planned as part of the normal disease-control programme and the feed had been ordered.
All males and affected females were injected with long-acting tetracycline (TM-LA) as soon as this could be arranged (26 weeks of age). Any injected females were segregated in hospital pens for 7 days after treatment and eggs discarded during that period.\par \par In addition to starting antibiotic medication the following advice was given:
1. Cull severely affected birds (especially with serious leg problems and/or nervous signs)
2. Facilitate access to drinking water, especially in the "hospital" pens (more drinkers) but also throughout the house (greater water depth).
Consider removing some of the flourescent tubes to reduce light intensity.
4. Re-litter as required (especially in bare areas identified).
5. Carefully monitor feed-intake and production to try to prevent a proportion of the females becoming over-fat (fatty liver problems are a potential risk).
6. Plan to supplement the males to make up for the ones lost through mortality or infertility due to chronic leg problems. Ideally one would wish to do this with fully-immunized birds (2 doses of vaccine 4 weeks apart then wait a further 2 weeks before movement). Some males will be available for transfer shortly (i.e. they must be removed from another farm within 2 weeks). In this case the best procedure would be to apply 1 dose of vaccine now and another when transferred, but keep them penned separately for another 2-3 weeks. Treat any (or all) of the replacement birds with long-acting injectable antibiotic at the first sign of any problem. In any case they should be injected when they are released, if they have not already been treated.
7. The next flock to be placed at this site should be vaccinated on the rearing site then carefully monitored after transfer.