Submitted to: Poultry Science Association Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: January 8, 1996
Publication Date: N/A
A continuous-flow(CF) culture of cecal bacteria from adult broilers administered to chicks increases their resistance to Salmonella typhimurium. Efficacy of this culture has been shown to be correlated with increased concentrations of propionic acid and volatile fatty acids. A poultry ceca Veillonella species isolated from this competitive exclusion CF culture ferments lactate with the production of propionate and acetate as the major volatile fatty acids. A defined medium was developed to quantitate the growth and metabolic characteristics of this microorganism. The final medium composition included 14%(v/v), phosphate buffers; 1% microminerals; 0.2%, B vitamins; 0.008%(w/v), amino acids; 0.03%, putrescine; 0.01%, each of adenine, xanthine, uracil; 0.005% guanine, and 5% CO2 saturated sodium carbonate. Cysteine (0.025%w/v) was included as the reducing agent. D-L lactate was added to the medium at 10, 20, 30, 40, 50, and 60 mM concentrations and growth was measured turbidimetrically at A600 nm in anaerobic batch culture. No growth occurred in the medium without added lactate and maximum A600 was reached at 60 mM lactate. Growth rates were significantly increased (P<0.05) as lactate concentration increased (10 mM, 0.20#0.006 h**-1; 20,0.34#0.002; 30, 0.42#0.006; 40, 0.47#0.004; 50, 0.51#0.001 and 60, 0.55#0.002) respectively. Similar results were observed with the nonpoultry species V. parvula and V. rodentium. This medium can be used for determining growth kinetics of lactate utilization and propionate production by this cecal poultry isolate.