Background:

Extensive interaction between gut microbiota and the host immune system has significant impact on chicken performance.

Objective:

Therefore, the influence of doxycycline, administered with or without Lactobacillus spp., on PepT1 and LEAP-2 mRNAs expression in duodenum, jejunum and liver was investigated in Duc chickens.

Methods:

One-day-old Duc broiler chickens were divided in four groups. Chickens without treatment served as controls. Five days after hatching the second group was treated with Lactobacillus brevis, L.plantarum and L.bulgaricus probiotics via feed for 15 days. The third group was treated with probiotics (as in group 2) and doxycycline (10 mg/kg bw, via drinking water for five days, started 15 days after hatching). The fourth group received antibiotic only as described above. Water and food (broiler starter without drugs) were supplied ad libitum. Samples from liver, duodenum and jejunum were collected at the end of the treatment with doxycycline (21 days after hatching).

Results:

Doxycycline administered alone or in combination with probiotics, provoked a statistically significant up-regulation of LEAP-2 mRNA in the liver and in the duodenum. Abundance of PepT1 mRNA was increased in the duodenum. Administration of doxycycline alone caused a moderate induction of LEAP-2 mRNA and down-regulation of PepT1 mRNA in the liver.

Conclusion:

Up-regulation of the studied antimicrobial peptides provoked by combination of Lactobacilli and doxycycline might be beneficial in terms of host protection.

Keywords: