Over the last 20 years, egg production in Africa increased by one million tonnes with more and more countries starting their own production. In times of high raw material prices, farmers have to reach a high productivity of their flocks with lowest mortality. Adequate chick management and feed supply are the two most important points in achieving this goal.
By Viola Holik , Lohmann Tierzucht, Dar es Salaam, Tanzania
Rearing is the key for a good production and all starts with the housing of day old chicks (DOC). Since the young birds are only vaccinated in the hatchery against certain diseases like Marek and sometimes Infectious Bronchitis/Newcastle Disease, they have limited protection against other diseases and therefore have to be isolated from older flocks. ‘All in all out’ is the best housing system to provide very good means of isolation and allows the entire farm to be cleaned and disinfected after each production cycle. If this system cannot be implemented, the distance between adult and brooding houses should be at least 100 meters.
Day old chicks cannot maintain their own body temperature for the first two weeks and therefore the correct house temperatures play an important role. If chicks are placed in an environment which is too cold, they will refuse to eat and drink which will lead to high mortality after 2-3 days. Especially in hot climates, farm managers tend to believe that heating is not important and often don’t even have a thermometer in the house. This big mistake causes the loss of expensive chicks together with a poor start for the flock and can easily be avoided: place several thermometers at chick level in the house, check them regularly before the arrival of the chicks and during the first two weeks (Table 1
The heating of the house has to start at least 24 hours before the chicks arrive in order to warm up the floor and the walls. Temperature at arrival should be 35-36°C at chick level with a relative humidity of 60%. The body temperatures of the chicks are a useful tool to determine if the house is warm enough. Normal body temperature of a DOC is 40-41°C and can be checked with a simple ear thermometer which should be placed gently at the cloacae. Take samples regularly and in case the average body temperature is for example 39°C, increase the temperature by 1°C.
Measuring nutrient content
Throughout their life, chickens have different nutrient requirements and only if these needs are fulfilled can they grow to their genetic potential. Many farmers in Africa mix their feed themselves which appears to be cheaper, but can be an expensive experience in the long run. Raw materials must be analysed for their nutrient content regularly, especially when regional by-products are used. Only based on this information can a formulation be calculated, otherwise the feed might not contain the necessary nutrients. All European countries have laboratories for agricultural purposes, like LUFA in Germany or the Food Standards Agency in England (see More Information
). Since raw material prices are rising, alternative feedstuffs for poultry feeds can be a solution, if the nutritional value is known (see Tables 2, 3
Some raw materials listed in these tables are described as ‘high fibre’. Based on new scientific literature and a lot of practical experience from different countries around the world, crude fibre will not harm any layer bird, neither during rearing (developer phase for instance) nor during the production period as long as the energy content of the feed is not being reduced. An increased content of crude fibre can even support a healthy digestion and very often will positively influence the birds’ behaviour.
If the chickens are housed in environmental controlled units, feeding formulations and methods can work as in moderate parts of the world. Many houses in Africa though, are open houses with no temperature control except fans and occasionally foggers and the chickens are more or less exposed to the outside heat.
With increasing temperatures birds reduce their feed intake to decrease the metabolic heat produced by digesting the feed whilst at the same time the energy required to cool down and maintain the body temperature of 40-41°C will increase. Therefore special measurements have to be implemented and it is very important that the feed density is high.
Pre-layer diets from week 17 to 5% of production are a good tool to support these birds, which are already starting to lay eggs and to stimulate the rest of the flocks. Only a few farmers in Africa are using them however, since they are worried about the additional work or consider it too complicated. In this case one can simply use the normal developer diet and adjust it to 2% of calcium, by adding roughly 2.5% of coarse limestone on top of the developer feed. During the production phase three different feeding programmes in 19-45 weeks, 46-65 weeks and after 65 weeks should be used in order to support the birds changing requirements, also a rare practice in Africa.
If these programmes are not implemented, at least 5 g of coarse calcium/bird/day should be offered to the layers after week 45, preferably in the afternoon/evening feeding to maintain good shell quality and liveability. An energy level of 11.4-11.6 MJ ME (2725-2770 Kcal)* has to be maintained in all layer feeds and the correct percentage of protein according to the breeders’ recommendations. The feed should be distributed as ⅓ in the morning and ⅔ in the evening, since the layer needs the energy and the calcium for the egg production during the night.
*energy based on German energy evaluation system