ARTICLE Introduction Microbiological monitoring in hatchery Rajesh Kumar, Raj Narayan Trivedi and Suhaib-Ul-Haq Department of Veterinary Microbiology College of Veterinary & Animal Sciences G. B. Pant University of Agriculture & Technology, Pantnagar A hatchery is a facility where eggs are hatched under artificial conditions. Poultry hatcheries produce a majority of the birds consumed in the world including chickens, turkeys, ducks and some other minor bird species. Hygiene is an important aspect of hatchery design and management. Hatchery hygiene is recognized as an important factor in healthy poultry production.Good hygiene is required for maximum hatching rates and chick quality. The protection from contamination of hatching eggs and day-old chicks or poults, particularly in the light ofspecific disease controls (e.g. Salmonella), is becoming increasingly relevant in the operation of hatcheries. Therefore, the development and maintenance of an effective hatchery sanitation and microbial monitoring program is essential for the successful operation of a poultry hatchery. Microbiological monitoring is an essential element of any hatching egg quality assurance program. The contamination of the eggs or the chicks can come from the breeder house, egg holding facilities, or the hatchery. Microbiological monitoring evaluates the hatchery sanitation program, the quality of the eggs entering and chicks leaving the hatchery. The monitoring program needs to be conducted on a routine basis, the results carefully interpreted, and the data filed in a manner which allows for review of data over time. Monitoring programs used in the hatchery can have two levels of intensity. The first level would be for the routine program. The second, more intense level would be used to solve a specific problem. The first level would include air and surface sampling. The second level would involve egg washes, chick sampling, and bacterial identification. Microbial Contamination Embryos may become infected with bacteria and moulds during incubation, and newly hatched chicks are very susceptible to infection with various microorganisms (e.g. Salmonellaspp., Escherichia coli, Pseudomonas spp., Proteus spp. and Aspergillus fumigates).Cracked eggs facilitate a marked increase in eggshell penetration by Salmonella spp. Asingle infected egg can contaminate large batches of clean eggs when the egg is accidentally broken, or as hatching occurs. Infection by E. coli can also occur in a similar manner.Magnitude of the microbial problems may be anticipated by the fact that a single egg can carry up to 30,000 microbes on the shell.The increase in numbers of microorganisms inside the hatchery is aided by the relatively high working temperature and humidity. The process of hatching and the work involved in removing chicks are accompanied by a massive increase in numbers of microbes, which originate from dead embryos,’pipped’ eggs, hatcher dust and fluff, and from the activities of personnel. These factors influence the level of microbial contamination of the chicks as they hatch, and affect their subsequent health and survival potential, especially during the first few weeks oflife. The hatchery and the surrounding environment should be cleaned regularly.Within the operating parts of the hatchery, the surface finish of floors, walls and ceilings must be ‘hard’, and suitable for washing by water applied under pressure.Similarly, the immediate surroundings of the building must be constructed of concreteor a similar impervious material, with adequate drainage. The drainage from inside and outside the hatchery must be designed to protect the environment from any pathogenic bacteria, viruses and moulds carried in the effluent. A variety of methods can be used in monitoring, depending upon the sample type and personal preference. When sampling the air in an area airplates or a mechanical sampler may beused. The swab and streak procedure or the RODAC plate procedure can be used to monitor flat surfaces. To monitor eggshell surfaces, the sterile tape procedure, the total egg wash procedure, or the egg rollon media procedures are appropriate. Chicks canbe sampled by the yolk sac swab procedure. Liquids may be monitored using media plates. While a variety of microorganisms can cause problems in the hatchery, not all types of microorganisms can be detected 94 February, <strong>2019</strong>
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