Meals for the egg a day layer

摘要

Genetic indications are that the current 2/3 eggs/bird/year increase will continue into the next decade and this rate of improvement could be even greater beyond 2010 as new biotechnology in genetics brings further break-throughs. This means that the commercial hybrid layer will have the genetic ability to produce an egg a day. The only thing standing in the way of achieving this will be the actual environment the bird lives in. The gain in egg numbers will to some part be due to earlier sexual maturity which has been advancing at one day each year. Although this may slow down it does present a down side due to possible smaller earlier eggs. This may not be a problem for those involved in breaking but is likely to be bad news for those producers requiring large eggs as early as possible in lay. The next 10 years is likely to see a shift in the correlation between body size and egg weight. Earlier maturing pullets will have the genetic ability to produce a heavier egg in the first 10 weeks of lay,at the same time preventing the egg from becoming too large in the subsequent period of lay. Key problem for the breeder will be determining how the market requirements will change rather than the provision of continuous genetic improvements. The advances in performance will require the geneticists and nutritionists to work closely together to successfully feed the 2010 hybrid. By this time flocks will be producing 340 eggs in 360 days, a rate of lay of 94 percent, and each day laying will be at a predictable time since ovulation and oviposition time will be very similar. Depletion age will be determined by both shell and internal egg quality but with flocks being kept longer by as much as 16 weeks. Providing shell quality can be maintained life spancould be extended further with these older eggs going exclusively for breaking. The two most concerning problems will be shell and bone strength, the latter being an important welfare issue under all management systems.