Chick quality assessment and incubation optimisation (3)
Part 3: Chick appearance by feathering
Chick quality becomes more and more important. A hatchery must produce qualitative chicks in order to meet the expectations of the farmer. This article will focus on assessment of chick quality based on appearance by feathering.
Frank Verschuere, Hatchery Development Department, Petersime NV
The feathering of day-old chicks is a vital factor of indicator for the total chick quality. This article discusses the most commonly seen issues of poor feathering and where to look for the potential causes. This will assist you in the continuous improvement of the chick quality in your hatchery.
What is the optimal appearance?
Chicks should have a uniform appearance with clean and dry feathers free from any materials, such as egg yolk and contaminated fluid meconium. The feathering on the head and neck of the day-old chicks is also important.
The following issues of poor feathering are commonly seen in the field. Each issue is associated with a potential cause.
Wet feathers are often related to an incorrect temperature during the late setter cycle or during the transfer period. Generally, 100.0°F egg shell temperature is optimal for incubation. However, for very young small eggs (with a low volume to surface ratio), 100.0°F egg shell temperature can result in excessive cooling. Whilst for very old large eggs (with a high volume to surface ratio), 100.0°F egg shell temperature can result in inadequate cooling and overheating.
Different breeds have different heat production curves. The heat production curve during incubation is also influenced by a number of hatchery specific factors: days of storage, pre-heating conditions etc.
It is important to fine-tune the incubation profile to have an optimal egg shell temperature during incubation. A real time egg shell temperature monitoring and controlling device, such as OvoScan™, is critical to ensure the correct egg shell temperature. This will result in a good hatch timing and hatch window, which will limit the amount of chicks with wet feathers at take-off.
An incubator that is set with eggs that have a wide variety in storage times, will result in a wide hatch window where the late hatchers will still have wet feathers at take-off.
It is important that the incubators receive preventive maintenance to ensure that the machines are always working correctly during incubation.
Early hatches and/or delayed take-off results in dirty chicks (chicks covered with meconium). In older flocks, a too high egg temperature after transfer is not unusual due to inadequate cooling. High temperature after transfer increases movement in the baskets. When the infertile or contaminated eggs are not removed during transfer, these eggs can be damaged and broken by the movement of the chicks and this can result in dirty chicks.
Poor uniformity of chick colour
Large hatch windows can result in a general poor uniformity, what can also be seen in a poor uniformity of chick colour. Large hatch windows can be induced by poor setter uniformity or incorrect loading of the setter according to flocks with a different heat production. This is often the case with very old machines or with multi-stage incubation.
Poor breeder house conditions or reduced collection times in the breeder house will contribute to this.
Flat feathering on head and neck
Either too high or too low temperatures during the last days of incubation contribute to flat feathers on head and neck. It is key to manage a good feathering by using the correct air temperatures related to the heat...
Do you already have an account? Log in here