Tags: Hatchery management | Whitepaper
August 27 2010
,Cleaning and disinfection are fundamental to effective hygiene in the hatchery. Cleaning can remove up to 85 per cent of micro-organisms, preventing their development by removing their food sources, or ‘dirt’. Any remaining micro-organisms can then be eradicated by disinfection.
However, a cleaning and disinfection programme is like fighting an invisible enemy and to evaluate its efficacy, that enemy can be made visible by monitoring.
Three options for effectively monitoring hatchery hygiene are:
1 Visual inspection
Regularly take a critical look at levels of cleanliness throughout the hatchery and its equipment. Use a checklist, on which dirty spots (such as remains of broken eggs, fluff) can be indicated and recorded. Pay special attention to hard-to-reach areas, like backside cooling coils, door rubbers, ventilation pipes and the suction heads of the transfer machine. When dirt is visible to the naked eye, there will certainly be many micro-organisms present.
2 Agar cultures for non-specific bacteria
Make the enemy visible with a non-specific bacteria count. When compared with a reference (see example in table), this will illustrate the efficacy of your cleaning and disinfection programme. Remember that pathogenic bacteria and other micro-organisms are likely to co-exist alongside non-specific bacteria, and some fungi can also be revealed by this procedure.
Methods for inspecting flat surfaces (e.g. walls, ceilings) include:
Whether you use swabs or Rodac plates:
After 24 - 48 hours, count and record the cultures. The number of colonies present indicates the hygienic state of the surface sampled. The evaluation of these counts should be based on the hatchery’s own criteria, or by the terms of a national or integration-wide quality programme. An example is given in the table.
3 Specific bacterial and fungal monitoring
To test for particular bacteria and fungi, specific plates contain a selective agar, formulated specifically to encourage growth or colonisation by the bacterium/fungi being investigated. Fluff, chick paper and other hatchery materials may also be prepared for monitoring in this way. For specific monitoring, it is often advisable to contact a specialised laboratory for sampling and/or an accurate interpretation of results.
Based on Rodac plates with a diameter of 5,5 cm; Number of samples and locations are specified. | |||
Colonies/Plate | Score | Average hatchery score | Rating |
No colonies | 0 | 0.0 - 0.5 | Excellent |
1 - 40 | 1 | 0.6 - 1.0 | Good |
41 - 120 | 2 | 1.1 - 1.5 | Reasonable |
121 - 400 | 3 | 1.6 - 2.0 | Moderate |
> 400 | 4 | 2.1 - 2.5 | Bad |
Uncountable | 5 | > 2.6 | Very bad |
Evaluation of bacterial counts according to Dutch standards (1999 Poultry Farming Hygiene Regulations).