Epidemiological Study of Campylobacter spp. in Broilers: Source, Time of Colonization, and Prevalence

Abstract

From October 1993 to August 1994, broiler chickens in four grow-out houses, two previously used (houses 1 and 2) and two newly constructed (houses 3 and 4), were used in a study to determine the source, time of infection, and prevalence of Campylobacter spp. Cecal droppings and cecal samples were obtained from the broilers. Samples were also obtained from water, feed, litter, soil, fans, and workers' boots. Samples were obtained from domestic animals and wildlife species (rectal swabs), including insects, on or near the premises. Broilers in houses 2, 3, and 4 became infected in the second or third week and were fully colonized by day 42. Campylobacter appeared in house 1 during week 2 in a low percentage of the birds, disappearing by the fourth week. Isolates were also recovered from domestic pigs and water on this farm. In house 3, the organism was isolated from workers' boots and a wild bird prior to isolation from the broilers. Following isolation from cecal droppings, the organism was isolated from water, feed, litter, feathers, flies, cattle, feces, and wild animals. In house 2, Campylobacter was isolated from cattle feces and wild birds prior to week 5, when the broilers first became infected, and thereafter from water, feed, insect, and wildlife, and cecal droppings. It was subsequently isolated from workers' boots, cattle feces, feathers, insects, and other wildlife. All ceca taken from 20 birds each from houses 2 and 3 were positive at time of slaughter (day 49). All ceca from house 1 were negative. No ceca were collected from birds originating in house 4. No specific source could be identified from the samples obtained, although apparently the organism permeates the environment and several potential sources are discussed in this paper.

Sources of Campylobacter Colonization in Broiler Chickens

“…In the United Kingdom and other European countries, where used litter is removed and houses are cleaned between flocks, longitudinal studies indicate that infection is not predictable from the Campylobacter status of the last flock in the house (26). Negative flocks often follow positive ones (6), and positive flocks can occur even in newly constructed broiler houses (37). There are no published reports of C. jejuni isolation from the floors and walls of emptied, cleansed, and disinfected houses (and many groups have searched).…”

“…Although such animals are unlikely to enter houses, they may excrete campylobacters in substantial numbers, and this can result in contamination of boots, other external clothing, and equipment taken into the houses. Certainly, genotypically identical strains can be found in cattle kept next to the broiler house and the broilers within the house (37,68), and the presence of other farm animals on the farms is a risk factor for flock colonization (35). Concrete aprons around houses that are regularly cleaned and disinfected, the enclosure of grazed areas, and restrictions on the freedom of movement of domestic pets should be effective measures to reduce these risks.…”

Isolation and Characterization of Campylobacter Bacteriophages from Retail Poultry

“…However, despite these documented outbreaks, Campylobacter continues to be a primarily sporadic disease (23). Campylobacters readily colonize poultry (9) and seem well adapted to the avian gut (4). This may partly explain the uphill battle of poultry farmers in the prevention of Campylobacter colonization of their flocks.…”

Detection of Thermophilic Campylobacter from Sparrows by Multiplex PCR: The Role of Sparrows as a Source of Contamination of Broilers with Campylobacter.

“…Jones et al [18] reported that any contamination of insects was generally external not internal since C. jejuni was not isolated after disinfection of the external surfaces of insects and suggested that contamination of broilers may not originate from insects. Gregory et al [13] reported that no specific contamination source could be identified but there were some potential ones outside of broiler houses like rodents and wild birds. However, the source of C. jejuni infection to broilers is not clear.…”