In a published paper, M. Mohiti-Asli of the University of Tehran in Iran and co-authors there and at the National Institute of Genetic Engineering and Biotechnology and Spain's Universidad Politécnica de Madrid report a 12-week experiment to study the effects of feeding regimen, inclusion of a fibre source, and crude protein content of the diet on performance of broiler breeder hens. The paper was published in Poultry Science.

In total, 360 hens and 60 males, 43 weeks of age, were assigned to 60 floor pens (six hens and one male each).

There were 12 treatments arranged factorially with two feeding regimens - restricted (R) and liberal feeding (close to ad libitum consumption; LIB) - three sources of fibre (zero, three per cent inulin or three per cent cellulose) and two levels of crude protein (14.5 or 17.4 per cent).

No interactions among main effects were observed for any of the traits studied, and therefore, only main effects are presented.

Body weight, liver weight and abdominal fat weight were higher (P<0.001) for the LIB than for the R-fed hens. However, egg production (P<0.001), fertility index (P<0.05) and percentage of hatch (P<0.01) were lower for LIB than for R hens.

The weights of ovaries (P<0.05) and the size of the first pre-ovulatory follicle (P<0.05) were higher for the LIB than for the R hens.

Egg yolk, egg weight and bodyweight of the hatched chicks were higher (P<0.001) for the LIB hens.

The inclusion of a fibre source in the diet decreased (P<0.05) feed intake, bodyweight gain, absolute liver and abdominal fat weight, and egg yolk weight. The effects were more pronounced (P<0.05) with cellulose than with inulin.

Hens fed additional fibre produced more (P<0.05) eggs that were more fertile (P<0.05) than control hens.

Crude protein content of the diet did not affect hen performance but reduced (P<0.01) the relative weight of the liver, ovary and abdominal fat.

The researcher concluded that the inclusion of inulin or cellulose in the diet improved hen performance and that an increase in dietary crude protein reduced obesity in broiler breeder hens.

Reference

Mohiti-Asli M., M. Shivazad, M. Zaghari, M. Rezaian, S. Aminzadeh and G.G. Mateos. 2012. Effects of feeding regimen, fibre inclusion, and crude protein content of the diet on performance and egg quality and hatchability of eggs of broiler breeder hens. Poult. Sci., 91(12):3097-3106. doi: 10.3382/ps.2012-02282

Further Reading You can view the full report (fee payable) by clicking here.

January 2013