Roughage Components in Nutrition of Layers – Does it Make Sense for Dual-Purpose Poultry?
Photo: Eva Wolf,
ÖTZ gGmbH
Dual-purpose chicken play some role in Swiss organic agriculture. Their feed efficiency is a challenge, though. Would it help to use more extensive and fibre-rich feed for such genotypes?
With the ban of killing one-day old chicks in Bio Suisse, dual-purpose genotypes gain importance as a means to produce male chicks that are suitable for fattening. However, also for hens of such strains and breeds feed conversion efficiency is, depending on the genotype, more or less limited. This leads to the question, whether less intensive feed components, as for example fibre-rich grassland-sourced forages could be appropriate to reduce waste of resources. That would be the more relevant, as laying hens on organic farms usually have access to grass feed in their outdoor yards.
Feeding trial with increased roughage proportions for layers
In a controlled feeding trial in barn we tested effects of a moderately increased dietary fibre content in a feed for layers. Furthermore, the voluntary grass intake from pasture was estimated in two flocks of layers on a commercial organic farm. In both cases, a newly developed dual-purpose strain was compared with classical layer hybrids.
The controlled experiment revealed, that increase of dietary crude fibre from 6.5 to 10% did not affect performance, egg weights or feed efficiency in any of the two genotypes. As expected, the layers from dual-purpose strain showed lower performance and feed conversion efficiency. This was not changed by diet composition.
Pasture can replace part of the compound feed for chicken
The on-farm study revealed and estimated feed intake from pasture at 25g dry matter per hen and day. The pasture swards had been young and nutritious. The resulting laying performance of both breeds was in the range of the expected. Since hens consumed less of the chicken feed in amounts similar to the intake from pasture, we estimate a relevant contribution of the grass to egg production reaching 20% of the diet. These figures are estimates based on biomass measurements on pasture and feed consumption in barn.
Dual-purpose chicken do not convert roughage-rich feed better than layer hybrids
We conclude that within the conditions of our studies a moderate elevation of dietary fibre contents in feed for laying hens did not impact on performance. Furthermore, increased fibre intake was naturally given by voluntary grass intake in outdoor runs. We did not find any specific advantage for the dual-purpose breed compared to the layer hybrids.
Conclusions
- The digestive tract of chicken is equipped for fermentative fibre degradation. Therefore, a certain level of fibrous feed components is an option. This may hold particularly true when less intensive chicken are used and outdoor run with grass swards is provided.
- Our studies have shown that at moderate levels part of feed protein for hens could be sourced and utilised from forages.
- A systematic assessment of land-use efficiency on poultry farms with outdoor run is still required.
Bibliographical reference
Hat der Raufutteranteil eine besondere Bedeutung für Zweinutzungshennen?.