Metabolisable energy content of rapeseed meal, soyabean meal and white‐flowered peas determined with laying hens and adult cockerels

Abstract

1. The apparent metabolisable energy (AME) contents of 5 protein‐rich ingredients were determined with laying hens and the true metabolisable energy (TME) with adult cockerels. The test materials consisted of one batch each of winter‐grown high glucosinolate rapeseed meal (HG‐RSM), summer‐grown HG‐RSM, low glucosinolate rapeseed meal (LG‐RSM), soyabean oil meal (SBM) and white‐flowered peas (WFP).

2. In a separate study the endogenous energy losses (EEL) of adult Rhode Island Red (RIR) and adult broiler roosters were measured when given a supply of energy.

3. AME value for RSM tended to be lower for cockerels than for hens, whereas the opposite was noted for SBM and WFP.

4. This study showed that AME of ingredients could be influenced by choice of technique. These differences are accentuated for some ingredients, such as SBM and RSM, although there was no difference in ranking ingredients tested within the AME and TME systems.

5. Assuming that birds are receiving an energy source, the EEL0 per kg metabolic body weight (W0.75) did not differ between adult broiler cockerels and adult Rhode Island Red cockerels.

6. The AME0 values with laying hens for winter HG‐RSM, summer HG‐RSM, LG‐RSM, SBM and WFP were 7.0, 7.6, 8.7, 11.5 and 11.3 kJ/g dry matter. TME0 values with cockerels for the respective ingredients were 8.4, 8.5, 9.5, 12.6 and 13.4 kJ/g dry matter.