An intresting article from http://www.fao.org/docrep/008/y5169e/y5169e05.htm
Skip it if its too much
Scavenging commercial hybrid layers in Sri Lanka
In a study carried out by Roberts and Senaratne (1992), Sri Lankan villagers reared hybrid egg layers in a semi-scavenging system. Day-old hybrid chicks were brooded under the heat of a small kerosene lamp. The chicks were provided with a little mixed supplement of local crop by-products, comprising 40 percent rice polish, 50 percent expeller coconut meal and 10 percent broken rice. The Proximate chemical analysis of this supplement was 16 percent Crude Protein, 8 percent Crude Fat, 7 percent Crude Fibre and 7 percent Ash.
The amount of the supplement increased from 8 to 60 g/bird/day until 12 weeks of age, and was maintained at 60 g thereafter. The growth rate was 38 g/bird/day up to 20 weeks of age. The mortality rate of the chicks was only four percent in the period up to ten weeks, which compared favourably with mortality of 68 percent up to six weeks in Indonesia (Kingston and Creswell, 1982) and 25 percent up to eight weeks in Thailand (Thitisak et al, 1989) in chicks hatched and reared by village hens. The comparative advantage of the Sri Lankan performance was attributed to supplementing the competitive scavenging, and to the protection against predators provided by the semi-intensive management system. It is probable that chicks would also benefit from the use of a simple creep feeder for feeding kitchen waste. The mortality rate, in the Sri Lankan example, increased after reaching eight months of age, perhaps due to a greater need for scavenger free-ranging, and almost reached a cumulated 60 percent loss by 13 months of age. Of the 142 hens lost up to 13 months of age, records were kept for 92. The causes of mortality were:
32 percent predators (such as dogs, mongooses, pole cats and snakes);
26 percent disappeared; (not stolen? lol)
15 percent Newcastle disease;
15 percent intestinal infection;
5 percent stolen;
4 percent accidents (vehicles and falling coconuts); and
2 percent attacked by humans.
Hens laid their first eggs when they reached 21 weeks (146 days) of age, although 40 percent production (on a hen/day basis) was not achieved until they were 30 weeks of age. Peak egg production was just over 60 percent. A severe drop in production (beginning when the hens were eight months of age) corresponded with an outbreak of Newcastle Disease in local village birds and the start of the long dry intermonsoon period. Production fell to below 30 percent when the hens were ten months of age, and slowly rose again to over 60 percent at 13 months of age. The recovery in production began during the dry period and was maintained into the next season. Egg production was comparable with that of hybrid egg layers, which were introduced into the village as pullets, provided with a supplement and allowed to scavenge.
The production was much better than the 12 to 21 percent reported in village birds in Indonesia (Kingston and Creswell, 1982) and in Thailand (Janviriyasopaki et al, 1989) and (Creswell and Gunawane, 1982). The egg weight reported by Roberts and Senaratne (1992) was 60 g compared with about 40 g for village hens (Kingston and Creswell, 1982).
Edited by ozexpat - 7/17/14 at 2:39am