RESUMO
OBJECTIVE: This study aimed to determine the appropriate supplementation level of lactic acid bacteria (LAB; Lactobacillus plantarum and Bacillus clausii), yeast (Saccharomyces cariocanus and Wickerhamomyces anomalus) for degrading free gossypol and glucosinolate in the fermented total mixed ration (TMR) containing cottonseed meal (CSM) or rapeseed meal (RSM), to improve the utilization efficiency of these protein sources. METHODS: For LAB, L. plantarum or B. clausii was inoculated at 1.0×108, 1.0×109, 1.0×1010, and 1.0×1011 colony-forming unit (CFU)/kg dry matter (DM), respectively. For yeast, S. cariocanus or W. anomalus was inoculated at 5×106, 5×107, 5×108, and 5×109 CFU/kg DM, respectively. The TMR had 50% moisture and was incubated at 30°C for 48 h. After fermentation, the chemical compositions, and the contents of free gossypol and glucosinolate were determined. RESULTS: The results showed that the concentration of free gossypol content was reduced (p<0.05), while that of the crude protein content was increased (p<0.05) in the TMR containing CSM inoculated by B. clausii (1×109 CFU/kg DM) or S. cariocanus (5×109 CFU/kg DM). Similarly, the content of glucosinolate was lowered (p<0.05) and the crude protein content was increased (p<0.05) in TMR containing RSM inoculated with B. clausii (1×1010 CFU/kg DM) or S. cariocanus (5×109 CFU/g DM). CONCLUSION: This study confirmed that inclusion of B. clausii with 1.0×109 or 1.0×1010 CFU/kg DM, or S. cariocanus (5×109 CFU/kg DM) to TMR containing CSM/RSM improved the nutritional value and decreased the contents of anti-nutritional factors.