Horizontal transmission ofCampylobacter jejuniamongst broiler chicks: experimental studies

Abstract

SUMMARYHorizontal transmission of Campylobacter jejuni was investigated in campylobacter-free broiler chicks. One hundred and twenty chicks housed individually, were provided with water containing 1O2-1O9 c.f.u./ml C. jejuni. Colonization was rapid [47 of 73 (64 %) positive cloacal cultures within 3 days and 65 of 73 (89 %) within 7 days], dependent on C. jejuni strain and inoculum size but independent of chick age. Groups of 5-24 chicks in isolators were exposed to C. jejuni-contaminated water or colonized seeder chicks. Transmission occurred in 2-7 days concurrent with a gradual increase of C. jejuni in litter, water and feed. Environmental samples were culture-negative within 3 days following removal of colonized chicks. Treatment of 1-day-old chicks with adult caecal microbiota did not affect colonization. Treated and control chicks were all C. jejuni-positive within 3 days of seeder challenge.

Epidemiological investigation of risk factors for Campylobacter colonization in Norwegian broiler flocks

“…The failure to demonstrate a relationship between campylobacter colonization and reduced productivity or disease, is in accordance with experimental findings which indicate that campylobacter is usually a non-pathogenic commensal in the gastrointestinal tract of chickens [11,37].…”

“…Thus, the finding that contact with other poultry and pigs was associated with an increased risk of campylobacter colonization in broiler flocks was not unexpected. This emphasizes the need for strict hygienic routines when the farm workers enter the rearing room and supports the suggestion that stringent hygiene barriers are required to prevent colonization during the rearing period [10][11][12]17]. Since campylobacters tend to die out rather than multiply in the environment under normal ambient conditions, transmission of the organism to subsequent flocks in the same house is probably interrupted by efficient cleaning and disinfection before restocking [11,17,18].…”

“…Chicks challenged experimentally with campylobacter-contaminated water become rapidly colonized [11]. The water supply was identified as the predominant source of C. jejuni on a broiler farm in southern England [25].…”

“…Theoretically, prevention of campylobacter colonization in poultry may be effected in a number of different ways including hygienic measures [10][11][12], vaccination [13,14], treatment with competitive exclusion microflora [15], and genetic control (selection of resistant chicken lines) [16]. Previous studies have indicated that it may be possible to maintain broiler flocks campylobacter-free up to the processing age by introduction of hygienic measures in the rearing houses [10-12, 17, 18].…”

PCR Detection of Four Virulence-Associated Genes of Campylobacter jejuni Isolates from Thai Broilers and Their Abilities of Adhesion to and Invasion of INT-407 Cells

“…Infection with C. jejuni or C. coli is characterized by the sudden onset of fever, abdominal cramps and diarrhoea with blood and leukocytes [7,8]. There are many possible sources of infection from C. jejuni and C. coli, as they are part of the normal intestinal flora in a wide range of birds and mammals and are transferred to other chickens during growth and processing [1,36]. Large-scale outbreaks of human campylobacteriosis are rare and are usually linked to the consumption of polluted water or raw milk.…”