IMPORTANCE

Although antibiotics can prevent and treat diseases, their overuse can be harmful. Despite this, the effects of orally administered florfenicol on intestinal health in broilers are unclear.

OBJECTIVE

This study examined oral florfenicol's effects on intestinal function in broilers to guide its clinical use.

METHODS

One hundred and twenty Arbor Acres broilers (8-d-old) were divided randomly into the control (N) and florfenicol groups (F). The broilers in group F were fed 100 mg/kg body weight florfenicol for seven days. On day 15, the broilers were euthanized and sampled to analyze fluid metabolism-related genes and proteins, jejunal morphological and microbiota.

RESULTS

The results revealed a decrease in body weight and an increase in diarrhea rate in broilers in group F compared to group N. The villus length and villus length/crypt depth (V/C) of the jejunum were lower in group F than in group N, whereas the crypt depth was higher. The levels of tumor necrosis factor α, Toll-like receptor 4, lipopolysaccharide, nuclear factor kappa-B, interleukin (IL)-6 and IL-10 in group F were higher in group F than in group N, whereas the levels of cyclic adenosine monophosphate and aquaporins (AQP) 4 and AQP5 were lower. were more abundant in group F than in group N, whereas , , and were less abundant.

CONCLUSIONS AND RELEVANCE

Oral florfenicol might adversely affect the intestinal mucosa, intestinal mucosal immune system, intestinal microbiota balance, and water metabolism in broilers. This study provides a theoretical basis for the rational use of florfenicol.