The aim of this project was to provide information on the suitability of current commercial layer strains for alternative (non-cage) management systems.
Equal numbers (1516) of ISA Brown, Hyline Brown and HiSex Brown day-old pullets were obtained from hatcheries on the same day, housed in floor pens and brooded and reared in accordance with the hatchery recommendations applicable to each strain.
Although beak trimming may be indicated as a standard procedure for some strains, for these trials birds were not beak trimmed. All birds were housed in the experimental accommodation by approximately twelve weeks of age.
The barn consisted of two 200-bird pens and one 500-bird pen of each strain in a randomised block design.
From 18 weeks of age, egg production and mortality were recorded daily with egg weights recorded fortnightly.
Numbers of eggs laid in each nest were recorded.
Feed intake was measured at 4 week intervals with bodyweight, feather condition, foot and claw condition, egg specific gravity and yolk colour recorded at three-monthly intervals.
Mortality in the barn system was 1.4% during month one and 2.3% for month two. During month three, mortality started to approach 5% (4.9%) and the decision was made to beak trim some of the birds in the barn to evaluate the effect on various parameters (1200 trimmed versus 1500 not trimmed).
ISA Brown birds had the lowest feed intake and FCR and the heaviest eggs in the barn and free-range systems.
Hyline Brown birds had the highest feed intake and egg production in the barn and free-range systems with the highest FCR in the free-range system.
HiSex Brown birds had the lowest egg production and the lightest eggs in both the barn and free-range systems, with the highest egg mass in the free-range system but the lowest in the barn and the highest FCR in the barn system.
Free-range had the highest mortality during the trial followed by barn and cage.
Within systems, Hyline Brown birds were the heaviest in the barn and free-range systems, followed by ISA Brown and HiSex Brown.
Previous diagnostic studies of underweight flocks have indicated problems with egg peritonitis and salpingitis, which was also observed in the present study. Salpingitis is inflammation of the oviduct and is found more frequently in birds on litter than in cages and is spread by contact between birds, or by contact between birds and faeces.
Following the comparison of the relative merits of the performance of ISA Brown, Hyline Brown and HiSex Brown birds in barn and free-range systems, the present trial found that Hyline Brown and ISA Brown were best suited to the free-range system and ISA Brown to the barn system. However, the mortality rates were unacceptable for all three strains in both systems.
Mortality decreased dramatically after beak trimming in the barn, however,
Beak trimming is not entirely effective in preventing feather pecking and cannibalism. If we are to reduce the need for beak trimming in the Australian flock further research needs to be done to develop a specific strain for each system and improvement of the management procedures for current commercial breeds for use in alternate systems.
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Article made possible through the contribution of the Australian Poultry Science Symposium (APSS) 2006.