Bacterial Population Changes in the Ceca of Young Chickens Infected with Eimeria tenella

Abstract

Eimeria tenella, a protozoan parasite belonging to the class Sporozoa, is the etiological agent of cecal coccidiosis of chickens. This organism goes through a typical sporozoan life cycle and, with the exception ofsporulation of the oocyst, all stages occur within the host's intestinal tract. Invasion of the intestinal epithelium by sporozoites and merozoites results in considerable tissue destruction and, in acute cases, severe hemorrhaging by the fifth day of infection, at which time mortality among the hosts reaches a peak. It has been known for some time that under certain poorly defined conditions intestinal bacteria of the chicken may invade the tissues and set up local infections in the liver, spleen, and other organs. Morse (1908) frequently found "Bacterium aerogenes," "B. coli," "B. proteus," and "Bacillus pyocyaneus" in various organs of chickens which had succumbed to "white diarrhea." Hadley (1909) found bacterial invasion of the viscera in chickens infected with Coccidium cuniculi. This bacterial invasion was studied further by Fantham (1910), who employed coccidia-infected wild grouse. He explained that the sporozoites and merozoites act "as inoculating needles," permitting injurious bacteria to pass into the tissue of the gut, "whence, by way of the blood and lymph, they can reach other organs." Many other workers have reported similar results, which are well reviewed and discussed by Ott (1937). The latter isolated Escherichia coli, Staphylococcus albus, Salmonella pullorum, and an unidentified coccus from the livers of 36 out of 46 one-year-old White Leghorn hens infected with Eimeria tenella. Ott found little evidence of bacterial invasion in normal, E. tenellafree chickens. By feeding broth cultures of E. coli to infected hens, he was able to increase the percentage of livers infected with this bacterium. Ott concluded that there is some relationship between cecal bacteria and cecal coccidiosis. Recently, Mann (1947) reported considerable success in stamping out cecal coccidiosis by increasing the carbohydrate and reducing the protein and roughage components in the ration. He believed that roughage "caused sufficient damage to the mucosa to pave the way for coccidial invasion." He also thought that the presence of roughage stimulated the activity of certain intestinal bacteria, which assisted coccidial invasion. Mann (1945a,b) previously found that roughage and protein stimulated proliferation of anaerobic intestinal bacteria,

The Intestinal Microflora of Hens as Influenced by Various Carbohydrates in a Biotin-deficient Ration

“…The few lactobacilli which were isolated were anaerobic to microaerophilic, and reduced litmus, produced acid, and coagulated skim milk within 24 to 36 hours at 37 C. Because of the difficulty in isolating and maintaining these lactobacilli, no further study was made of them. The enterococci were not studied to any great extent, but those encountered in the feces of young chicks have been partially characterized and found to be Streptococcus faecalis (Johansson and Sarles, 1948). Coliform bacteria appeared to be predominately of the E. coli and inter- Each count is the average of two samples and is given on a fresh weight basis.…”

Intercurrent coccidiosis and necrotic enteritis of chickens: rational, integrated disease management by maintenance of gut integrity

“…Gut damage caused by coccidial infection sometimes predisposes birds to clostridial infection and NE, which is apparently supported by a UK field survey (Hermans & Morgan, 2003). Certainly, coccidial infections stimulate proliferation of intestinal C. perfringens (Johansson & Sarles, 1948;Bradley & Radhakrishnan, 1973;Kimura et al ., 1976;Dykstra & Reid, 1978;Waldenstedt et al ., 1998). Leakage of plasma proteins due to coccidiosis can provide growth factors for the proliferation of C. perfringens (Van Immerseel et al ., 2004).…”

“…Association with bacteria . Although coccidioses in chickens appear to occur in the absence of other organisms, Johansson & Sarles (1948) considered that bacteria such as Clostridium perfringens and coliforms might be involved in the pathology of E. tenella . Similar findings regarding E. tenella and E. brunetti were reported by other workers (see .…”

Necrotic enteritis in broiler chickens: disease characteristics and prevention using organic antibiotic alternatives – a comprehensive review

“…Before the current name, Clostridium perfringens was first called Bacillus welchii and then renamed Clostridium welchii , which was isolated from intestinal lesions of Black Orpington pullets in Australia ( Bennetts, 1930 ). Thereafter, the disease was induced by feeding C. perfringens culture to chickens and called the “six-day disease,” as the bacteria were observed to infect the intestinal mucosa of birds ( Johansson and Sarles, 1948 ). However, the term “necrotic enteritis” was coined and reported by Parish in 1961 in England.…”