PROIMI   05436
PLANTA PILOTO DE PROCESOS INDUSTRIALES MICROBIOLOGICOS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
A diet rich in soybean agglutinin (SBA) administered to BB chichs modifies gut microbiota and body weight gain
Autor/es:
BABOT, JAIME DANIEL; ARGAÑARAZ MARTÍNEZ, ELOY; APELLA, MARÍA CRISTINA; PÉREZ CHAIA, ADRIANA
Lugar:
Córdoba
Reunión:
Congreso; XI Congreso Argentino de Microbiología General - SAMIGE; 2015
Institución organizadora:
SAMIGE
Resumen:
The components of broilers diet contain secondary products of plant metabolism, lectins among them, which act as defence mechanism in vegetables. These proteins show remarkable resistance to heat,pH and proteolysis so they can overcome pre-treatments and digestion, and reach the intestine active. Dietary lectins may impair intestinal epithelia development and enzyme digestive activity with theconsequent growth depression. Besides, changes in the intestinal microbiota may occur. In Argentina, poultry feeds contain high amount of soybean proteins, SBA among them. Classic diets contain 67-204 μg SBA/g of feed, a concentration that may not exert negative effects on the microbiota. The content of soybean protein on the diet could be higher but is limited by toxic effects attributed to SBA. Thus, the aim of this work was to purify SBA from soybean, elaborate a SBA-rich diet and evaluate its effect on caecal microbiota of BB chicks. To do this, soybean grains were peeled and crushed. Several ratios of grains/water and different (NH4 )2SO4 concentrations were evaluated to assess the conditions for the highest SBA yield and purity. SBA purity was determined by PAGE, and its titre by hemagglutinating activity. Semipurified SBA was sprayed over a regular diet for broilers to obtain a concentration of 217-354 μg SBA/g of feed. One-day-old BB chicks were daily fed this diet for 13 days (group S). A control group (group C) including birds fed the same diet but without the SBA supplement, was also evaluated. Animals´ weight and feed intake were daily assessed. Chicks were sacrificed before the start of the trial and on days 6 and 13, and caecal content samples were taken to assess microbiota composition by FISH using fluorescent probes, and fermentation products (FP) by HPLC. Birds of group C showed significantly higher weight than those of group S from day 7 on. Caecal microbiota showed predominance of Lactobacillus and Enterococcus on newly hatched chicks. Bifidobacterium population decreased on day 6 in chicks of group S, but recuperated on day 13, whilst it kept relatively constant in birds of group C. Bacteroides counts decreased on day 13 for animals of group S, but remained constant in birds of group C. Animals of both groups showed similar FP patterns on day 6 and 13. In conclusion, the higher amount of SBA in the feed led to a decrease in Bifidobacterium counts at the first week of chicks? life and the concomitant delay on body weight gain of birds. This suggest that intestinal microbiota of BB chicks may be reinforced with Bifidobacterium sp. to counteract the negative effect of a soybean diet with high lectin content.