Research files are added periodically on a range of topics found in this library. Library resources consist of old and new research related to the egg production and processing industry.
The impact of hen housing on egg production performance and egg quality was studied by the Coalition for Sustainable Egg Supply (CSES) study which analyzed eggs for shell strength, shell thickness, Haugh unit, vitelline membrane properties and egg solids. 24 eggs were randomly selected and assessed from each housing system. Diets were specifically formulated for conventional cage, aviary and enriched colony systems based on hen productivity and feed ingredients available while being cost efficient. Dietary changes were found to have the most impact on shell parameters, vitelline membrane parameters and egg total solids contrary to the laying hen housing system. Specific dietary changes and results for each element may be found in the article. Further research needs to be conducted in controlled research settings to determine any affect on housing systems on egg quality.
A two-part study measured hen performance in relation to space allowance. At 18 weeks old, four groups of Lohmann Selected Leghorn Lite hens were housed in either smaller furnished cages (SFC) or larger furnished cages (LFC) with access to nesting areas, perches and scratch mats. Two stocking densities for each type of cage were used: 748 cm 2/hen (116 in 2/hen) and 520 cm 2/hen (81 in 2/hen). Feed was given five times a day. At weeks 30, 50, 60 and 70; 20% of the hens were randomly selected to evaluate production parameters such as hen day egg production, egg weight, egg shell deformation, breaking strength of femur, tibia or humerus, birds suffering from keel bone deformations or foot health scores. While performance and mortality were not significantly affected by cage size or space allowance, hens with less space had higher feed disappearance and poorer feather cleanliness and condition; hence, the animal welfare was found to decrease with lower space allowance. There was no difference in bone strength or foot health scores between the two treatments.
Split feeding was tested as a strategy to improve shell quality in laying hens. The experiment was conducted in brown laying hens from 39 – 85 weeks of age, changing the diet in three phases to coincide with the hens’ age. Both diets had the same amount of fine and coarse limestone available in a 30:70 ratio. The split feeding style diet fed 30% of limestone in the morning and 70% of limestone in the afternoon, while the conventional feeding style fed the same diet in the morning and afternoon. 120 eggs were collected per feeding system and assessed. Bone strength was also measured. The results concluded that split feeding did not improve performance or shell quality; however, this might be due to flock health problems incurred during the study.