Commercial application of heat treatment during storage
Last month, we explained why short periods of heat treatment in case of long storage times are beneficial for early embryonic development, zooming in on the biological background. In this article, we put this knowledge into practice: how can this treatment successfully be introduced in a modern-day hatchery?
By Roger Banwell, Hatchery Development Manager
The challenge: intensity and frequency of the treatment
Research has indicated that in order to achieve consistent results, heat treatment during storage needs to be applied under very specific conditions.
For instance, if the frequency of the treatment is not accurate, the gains will be limited, or worse, some embryos will develop beyond the “point of no return”, as illustrated in Figure 1. This means that the embryos have advanced to beyond the formation of the primitive streak and that embryonic development can no longer be stopped. Putting these eggs back into the egg storage room negatively affects their viability.
Equally critical are the absolute temperature and transition durations. Figure 2 shows that an excessive treatment, e.g. when the eggs are heated up too fast or up to a too high temperature for too long, will also bring the embryos beyond the point of no return.
Finding the correct parameters
Aviagen has made major strides in identifying the optimum temperature, timings and operating temperature bandwidth for heat treatment during storage.
It is crucial to achieve the correct egg shell temperature. The eggs need to be heated up to an egg shell temperature of more than 32°C; yet keeping the temperature above 32°C for too long will negatively affect hatchability (Aviagen, 2014). Another important factor in the process are the warming-up and cooling-down phases.
Therefore, Petersime has developed an incubator dedicated to heat treatment during storage: the BioStreamer™ Re-Store. As it is equipped with the patented OvoScan™ technology, the egg shell temperature is precisely monitored and controlled during the entire heat treatment process. Moreover, the machine guarantees an accurate, controlled and uniform warm-up and cool-down phase as this is vital for the consistency of the results.
Petersime has used this dedicated Re-Store incubator, with a capacity of 57,600 eggs, to run several large scale trials. In a first phase, trials were conducted with grandparent flock eggs with a successful outcome in terms of egg shell temperature control, temperature uniformity throughout the incubator, consistency of the warm-up and cool-down phases and hatchability restoration. The internal environment throughout the entire treatment cycle was controlled based on egg shell temperatures.
In a second phase, trials were conducted in a commercial broiler operation. During these trials, hatchability, chick quality and post-hatch performance data have been acquired and analysed. Recent trials based on 12 - 15 days of storage result in an almost complete restoration of losses both in terms of hatchability and post-hatch final weights. This confirms the huge potential of the heat treatment methodology.
Heat treatment during storage has great potential in restoring the hatchability and even improving post-hatch performance. It is crucial, however, to accurately control the key incubation parameters, as inadequate application of the technique will result in suboptimal results or perhaps even lead to major losses. Petersime’s BioStreamer™ Re-Store ensures the precise measurement and control of the egg shell temperature in the incubator, as well as controlled and uniform warm-up and cool-down phases of the eggs – two key elements to achieve consistent gains.
Aviagen, How to improve the hatchability of stored eggs. (2014)