A Scottish Egg Hatchery decided to test Huwa-San as egg disinfectant against Formaldehyde, a common used product in egg disinfection.

The following criteria had to be met in order to achieve a beneficial result :

• Significantly reduce the infection on the eggshell.
• Have no negative influence on the hatching rate.
• Provide sufficient bacterial reduction in the hatching chamber.
• Have no negative influence on the vitality and the appearance of the chicken.
• Exposure to the product must be safe for the user.
• The product must be environmentally friendly.

The Egg Process Steps :

1. Collecting the eggs
2. Sorting of the eggs
3. Egg disinfection
4. Eggs are put in the incubation chamber
5. Incubation of the eggs
6. Placing the eggs in the hatching chamber
7. Hatching out of the chickens
8. Sorting of the chickens

Disinfection with Formaldehyde
Disinfection at Stage 3
The eggs are gassed during 15 – 20 minutes with formaldehyde gas in a specially constructed disinfection chamber. After disinfection the chamber is aired with clean air for 45 minutes. The formaldehyde gas is obtained by electrically heating paraformaldehyde powder.
Disinfection at Stage 7
On the 18th day of the hatching process (total of 21 days), the eggs are moved from the incubation chamber to the hatching chamber, where the eggs are disinfected a second time. This is traditionally done using formaldehyde, which when mixed with potassium permanganate immediately volatizes. The formaldehyde, which is placed in a small tray under the hatching trays, slowly evaporates.

Disadvantages of Formaldehyde
The first disinfection with formaldehyde gas, prior to incubation, is only effective against microorganisms on the surface of the egg-shell. The gas does not penetrate into the pores of the eggshell and microorganisms present in the pores are not eliminated. During incubation these bacteria and fungi remain viable.
Another consequence of the formaldehyde treatment is the intense yellow colour the hatchlings have. This colour often is associated with health and vitality. Spelderholt, a Dutch poultry research centre, investigated the effect of formaldehyde disinfection in the hatching chamber. The results of these tests clearly demonstrated that the death rate for hatchlings treated with formaldehyde gas was equal to that of the untreated hatchlings. The cause of death however was different. Without the formaldehyde treatment the hatchlings died of navel and yolk sac infection, however when using formaldehyde an equal amount of hatchlings died from breathing problems. Furthermore, formaldehyde belongs to the Carcinogen group I. The substances in this group strongly promote the formation of malignant tumours and may cause permanent damage to the DNA structure.

Formaldehyde did not meet the criteria described above. Although the product often is used in egg disinfection, it did not provide sufficient disinfection. It also has a negative influence on the hatching rate. Moreover, as a carcinogenic product it is not environmentally friendly and can be harmful to animals and humans.

Disinfection with Huwa-San
The correct dosage of Huwa-San was added to the water (2-3%). To insure a thorough contact between the egg-shell and the disinfectant the eggs must be sprayed or immersed until they are entirely soaked. This only takes a short time (5-10 seconds) for each egg.

Benefits of the Huwa-San treatment
All eggs disinfected with Huwa-San had a zero bacterial count level after 45 minutes. They remained bacteria free for several weeks. Eggs disinfected with common chemicals show an increase in bacteria after 20 minutes. Huwa-San also scored a 10.8% higher hatching percentage.

Huwa-San ensured an effective, long-lasting disinfection. Being environmentally friendly, the product was totally harmless to the user and the animals. Moreover, it had a positive effect on the hatching rate.

More information and specific data are available upon request.