ARS | Publication request: INFLUENCE OF RELATIVE HUMIDITY ON HORIZONTAL TRANSMISSION OF CAMPYLOBACTER JEJUNI IN BROILER CHICKENS

Submitted to: Campylobacter Helicobacter and Related Organisms International Workshop
Publication Type: Abstract Only
Publication Acceptance Date: June 15, 2005
Publication Date: September 6, 2005
Citation: Line, J.E. 2005. Influence of relative humidity on horizontal transmission of campylobacter jejuni in broiler chickens [abstract]. Campylobacter Helicobacter and Related Organisms International Workshop. p. 118.

Technical Abstract: Horizontal transmission of Campylobacter jejuni among broiler chickens has been documented; however, the influence of relative humidity (Rh) on transmission rates is an important factor that has not been extensively studied. The purpose of our experiments was to determine the rate of C. jejuni colonization among groups of broilers raised in microbiological isolation under high (approximately 80%) and low (approximately 30%) Rh conditions. Day of hatch chicks (n = 100 per group) were placed on wood shavings in high and low humidity controlled pens and challenged with C. jejuni by introducing two seeder birds orally inoculated with C. jejuni into each group. The rate of colonization was monitored by analyzing ceca from 10 chicks from each group at days 1, 2, 3, 4, 7 and 14. At the conclusion of the trial all chickens were removed and 100 newly hatched chicks were placed on the contaminated litter and a second trial was conducted with the litter as the only inoculum source. Trials were repeated in this manner with the time between removing birds and placing newly hatched chicks extended to 6h, 24h and 72h. Significant differences in Campylobacter colonization rates were observed between chickens raised under the high and low Rh conditions. A delay in colonization was observed in birds raised under the low Rh conditions which increased with the increased time between removal of birds and placement of newly hatched chicks. These experiments demonstrate the importance of humidity in horizontal transmission of Campylobacter and could lead to practical applications to help reduce Campylobacter colonization in broilers.