Comparative ileal digestibility of amino acids in 00-rapeseed meal and rapeseed meal fed to growing male broilers
Rapeseed meal (RSM) is a commonly used protein source in poultry diet but its usage is limited due to antinutritional factors, the glucosinolates (GLS) and erucic acid. The 00-rapeseed meal (00-RSM) is the developed variety of rapeseed with reduced GLS and erucic acid content through genetic selection. The present study was conducted with the objective of comparing the standardized ileal digestibility (SID) of amino acids (AA) in 00-RSM and RSM when fed to growing broilers. Three samples of each ingredient were collected from different sources. Two hundred and fifty two day-old male broilers (Hubbard × Hubbard) were fed a corn-soybean meal based starter diet in crumble form from day 1 to 13. On day 14, all chicks were individually weighed and randomly distributed to 42 replicate pens (6 birds in each pen). Six test diets (2 ingredient × 3 samples) with approximately 20% crude protein were made in mash form in such a way that the 6 test ingredients served as the sole source of AA in one diet. The endogenous AAs (EAA) were determined by feeding a nitrogen-free diet to six replicate pens. Each test diet was fed to six replicates of broiler chicks from 14 to 21 days of age. Results indicated that the SID of all AA differed (P < 0.001) among 00-RSM samples. Among RSM samples, the SID of AA varied for arginine, methionine (P < 0.01), histidine, leucine, lysine, aspartic acid, and phenylalanine (P < 0.05). A greater (P < 0.05) SID of all AA except arginine, histidine, phenylalanine, cysteine, and glutamic acid was observed in 00-RSM compared with RSM. In conclusion, 00-RSM had greater SID of AA compared with RSM and it is nutritionally superior to RSM to be used in broiler diets.