Evaluation of day of hatch exposure to various Enterobacteriaceae on inducing gastrointestinal inflammation in chicks through two weeks of age

ABSTRACT Inappropriate microbial colonization can induce gastrointestinal (GI) inflammation may predispose poultry to opportunistic infections and reduce growth performance. Four independent experiments were completed to test ability of select Enterobacteriaceae isolates to induce GI inflammation. Experiments 1 and 2 included a non-inoculated control (NC), and a low (L), medium (M), or high (H) day of hatch (DOH) oral inoculation level. In experiment 1, birds in L1, M1, and H1 received 102-104 CFU of a mixed dose of two species of Citrobacter and Salmonella Enteritidis LB (SE). In experiment 2, birds in L2, M2, and H2 received 103-105 CFU of E. coli LG (LG) and included NC. Body weight was recorded on d0, 7, and 14, with blood collected for chicken serum alpha-1-acid glycoprotein (A1GP) measurements on d14. Neither experiment resulted in differences in BWG, however, A1GP was increased (p