[Relation between creatinine excretion in the urine and feed protein quality in the growing pig]

N-balance experiments, in which creatinine excretion in urine was measured, were carried out with 80 female fattening pigs. 16 protein sources of different quality were used. In addition to that, an N-increase experiment--protein quality remaining the same--and N-free experiment and results from literature were included into the assessment. The b-value (Gebhardt, 1963) served as the criterion for protein quality. The creatinine coefficient (mg creatinine in urine per kg live weight and day) could be determined as 40.2. There was a direct relation between the N-balance value and creatinine excretion, not however, in the N-increase experiment. Significant relations to the protein quality (b-value, Gebhardt, 1963) could only be established when N-excretion in urine was included.