AGE, DIET AND SECTION: NEW INSIGHTS INTO THE IMMUNE BARRIER BUILDING IN AN AVIAN MODEL, THE QUAIL

LUCIANA MOINE; VIRGINIA PIQUERAS; SILVIA CORREA; CRISTIAN JAIME; NICOLÁS NAZAR

Mar del Plata

Congreso; REUNIÓN DE SOCIEDADES DE BIOCIENCIAS 2022; 2022

Colonization is the first step in the establishment of a diverse bacterial community in the gut. In mammals, the first contact with the microbiota occurs in the birth canal, and this inoculum is modulated by lactation. In birds, colonization begins during hatching by contact with environmental microorganisms. Therefore, studying immune parameters along a different colonization process in an avian model is highly relevant. We evaluated Japanese quail (Q, C. coturnix) at 7, 9, 14, 16, 21, and 28 days of age (DA); on DA 28, the rearing boxes were divided in two: maintained with starter food (SF) or changed to adult food (AF). Both groups were also studied on DA 35 and 42. Bi- or tri-factorial analyses were performed using ANOVA. Effects of Age, Section (duodenum vs colon) and Diet (starter vs adult) on bacterial density (flow cytometry), mucin production (colorimetric assay) and Bursa cellularity were studied. The bacterial density/mg of feces did not show differences with Age or Diet. Mucin analysis showed a significant interaction effect between Age and Section (p=0.0164) in SF-Q. Between 35 and 42 DA, significant effects were observed for the double interactions between Diet and Section (p=0.0059) and Age and Section (p=0.0264), and a trend for the interaction between Age and Diet (p=0.0582). Mucin values in the duodenum remained stable in the studied period, perhaps by early maturation in goblet cell density for this region. Regardless of the Diet, the colon’s mucin values were significantly higher by 42 DA. In terms of bursal cellularity, between 35 and 42 DA there was a trend for the double interaction between Age and Diet (p=0.0598). The diet was able to modulate mucin production in the colon at different DA as well as the cellularity of the Bursa. Together, our data provide insights into the relevance of Age, Gut Section, and Diet on immune barrier development in Q along the first 42 DA, thus helping to understand the initial host-microbe interaction in birds.