CIDCA   05380
CENTRO DE INVESTIGACION Y DESARROLLO EN CRIOTECNOLOGIA DE ALIMENTOS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Poultry-feed preservative potential of whey fermented with kefir grains
Autor/es:
ALEJANDRA LONDERO; ÁNGELA LEÓN PELÁEZ; GABRIELA DIOSMA; GRACIELA DE ANTONI; ANALÍA G. ABRAHAM; GRACIELA L. GARROTE
Lugar:
San Miguel de Tucum¨¢n
Reunión:
Simposio; IV Simposio Internacional de Bacterias Lácticas (SIBAL); 2013
Institución organizadora:
CERELA
Resumen:
Fungal contamination of poultry feed causes economic losses to industry and represents a potential risk to animal health. The aim of the present study was to analyze the application of a by-product of dairy industry fermented with kefir grains as an additive to reduce fungal incidence on poultry feed. For this purpose, first the innocuousness and the effect on intestinal microbiota of the fermented whey were studied in vivo. Twelve broiler chickens Ross PM3, 14-day-old, were divided in 2 equal groups: i) did not receive treatment and ii) received whey fermented with 10 % w/v of kefir grains (1 ml/chicken per day). The excreta moisture, the feed and water intake, along with the body weight were recorded daily for each chicken during 10 days. At the end of treatment the Eubacterial and Lactobacillus community of the ileum were analyzed by denaturing gradient gel electrophoresis. The antifungal activity of fermented whey against Aspergillus flavus, Aspergillus parasiticus, Aspergillus terreus, Aspergillus fumigatus, Penicillium crustosum, Trichoderma longibrachiatum, and Rhizopus sp. was assessed by determining its capacity to inhibit conidial germination. Then, the fermented product was added to poultry feed (1g/m1) and dried in a convection oven at 50 °C. The survival of kefir microorganisms during storage for 0, 15, and 30 days was determined by viable counts on MRS and YGC agar. Finally, the resistance of the added feed to fungal contamination was analyzed. It was fractionated on Petri plates (10 g feed/plate) and sprayed with 0.1 ml of a conidial (105/ml) suspension. Plates were incubated at 20 °C and checked daily to determine the time (in days) at which moulds become visible in the feed. Whey fermented with kefir grains was innocuous to chickens since there were not significant differences between control and treated groups for any of the parameters evaluated, whereas changes in Lactobacillus community of the ileum were detected. The fermented product showed high percentage of conidial germination inhibition (≥ 70%) on all fungal species evaluated. Furthermore, poultry feed added with the fermented whey was 2 to 4 times more resistant to fungal contamination than control feed depending on the fungal specie. It also contained 1 x108 colony forming units (CFU) of lactic acid bacteria/kg and 6 x107 CFU of yeasts/kg even after 30 days of storage. Therefore whey fermented with kefir grains can be added to poultry feed as biopreservative improving its resistance to fungi contamination and constituting a source of safe microorganisms potentially beneficial to chicken health.