Typhlitis--the death of my baby buff orp

From what i read in wikipedia , about what this means for humans, i would say that the best way to prevent it must be to keep a healthy gut flora (plenty of healthy probiotics, minimal antibiotics) and to reinforce a strong immune system.

That's just from what i read.

If you already knew that then, here's another bump.
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Identification of Brachyspira hyodysenteriae and Other Pathogenic Brachyspira Species in Chickens from Laying Flocks with Diarrhea or Reduced Production or Both
Anneke Feberwee,1* David J. Hampson,2 Nyree D. Phillips,2 Tom La,2 Harold M. J. F. van der Heijden,1 Gerard J. Wellenberg,1 R. Marius Dwars,3 and Wil J. M. Landman1
Animal Health Service (GD), P.O. Box 9, 7400 AA Deventer, The Netherlands,1 School of Veterinary and Biomedical Sciences, Murdoch University, Murdoch, Western Australia 6150, Australia,2 Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands3

Received 14 September 2007/ Returned for modification 20 November 2007/ Accepted 28 November 2007


ABSTRACT
Top
ABSTRACT
INTRODUCTION
MATERIALS AND METHODS
RESULTS
DISCUSSION
REFERENCES


Cecal samples from laying chickens from 25 farms with a history of decreased egg production, diarrhea, and/or increased feed conversion ratios were examined for anaerobic intestinal spirochetes of the genus Brachyspira. Seventy-three samples positive in an immunofluorescence assay for Brachyspira species were further examined using selective anaerobic culture, followed by phenotypic analysis, species-specific PCRs (for Brachyspira hyodysenteriae, B. intermedia, and B. pilosicoli), and a Brachyspira genus-specific PCR with sequencing of the partial 16S rRNA gene products. Brachyspira cultures were obtained from all samples. Less than half of the isolates could be identified to the species level on the basis of their biochemical phenotypes, while all but four isolates (5.2%) were speciated by using PCR and sequencing of DNA extracted from the bacteria. Different Brachyspira spp. were found within a single flock and also in cultures from single chickens, emphasizing the need to obtain multiple samples when investigating outbreaks of avian intestinal spirochetosis. The most commonly detected spirochetes were the pathogenic species B. intermedia and B. pilosicoli. The presumed nonpathogenic species B. innocens, B. murdochii, and the proposed "B. pulli" also were identified. Pathogenic B. alvinipulli was present in two flocks, and this is the first confirmed report of B. alvinipulli in chickens outside the United States. Brachyspira hyodysenteriae, the agent of swine dysentery, also was identified in samples from three flocks. This is the first confirmed report of natural infection of chickens with B. hyodysenteriae. Experimental infection studies are required to assess the pathogenic potential of these B. hyodysenteriae isolates.


INTRODUCTION
Top
ABSTRACT
INTRODUCTION
MATERIALS AND METHODS
RESULTS
DISCUSSION
REFERENCES


Avian intestinal spirochetosis (AIS) is a disease complex that affects commercial laying and meat breeder chickens, characterized by the colonization of the ceca by members of one or more species of anaerobic intestinal spirochetes of the genus Brachyspira (formerly Serpulina) (11, 14, 36). The condition is associated with delayed or reduced egg production and a chronic diarrhea in adult birds that can result in wet litter and fecal staining of eggshells. Moreover, reduced performance has been reported for broiler chicks hatched from eggs of breeder chickens infected with Brachyspira spp. (7, 33).

AIS was first clearly described in the 1980s, in both The Netherlands (5, 7, 8) and the United Kingdom (10), and subsequently has been reported in the United States (39, 43), Australia (24, 35), and a number of other European countries (2, 3). The nonspecific nature of the disease and the lack of availability of simple and specific diagnostic tests for these anaerobic spirochetes from chickens may have resulted in the condition being greatly underreported (14).

Studies using multilocus enzyme electrophoresis showed that intestinal spirochetes from chickens could be divided into at least six species groupings (25). These included the three species currently considered to be pathogenic to chickens, Brachyspira pilosicoli, B. intermedia, and B. alvinipulli (13, 37, 34, 40), as well as B. innocens, B. murdochii, and the proposed species "B. pulli" (35) that are generally considered to be nonpathogenic in chickens (35, 36). In several studies, other unidentified Brachyspira isolates of unknown pathogenic significance also have been identified in chickens (25, 27, 38).

In both Europe and Australia, the two most frequently reported pathogenic Brachyspira species in cases of AIS have been B. intermedia and B. pilosicoli (2, 3, 7, 25, 35, 38), while in the United States only pathogenic B. pilosicoli and B. alvinipulli have been recorded to date (39, 40, 43). In recent years, there has been only one brief conference report (45) regarding the occurrence of Brachyspira spp. infections in commercial poultry in The Netherlands; hence, the purpose of the current study was to determine which species are most commonly encountered in this region in poultry flocks with symptoms consistent with AIS. After selective anaerobic culture, isolates were identified using phenotypic traits and PCR-based methods. Significant new findings included the identification of the porcine pathogen B. hyodysenteriae (the agent of swine dysentery) in chickens from three flocks as well as the first identification of B. alvinipulli in chickens in Europe.


MATERIALS AND METHODS
Top
ABSTRACT
INTRODUCTION
MATERIALS AND METHODS
RESULTS
DISCUSSION
REFERENCES


Source of samples. The cecal samples that were examined originated from laying chickens from 25 flocks with symptoms associated with AIS and were submitted to the Animal Health Service (GD), Deventer, The Netherlands, for diagnostic purposes. Live chickens were stunned using CO2 plus O2 and exsanguinated, and a general routine postmortem examination was performed. The cecal contents initially were subjected to an indirect immunofluorescence antibody test (IFAT) for the detection of Brachyspira spp., and then 73 samples positive by IFAT were selected for further examination. Forty-three of the 73 samples were derived from laying chickens on 23 farms located throughout The Netherlands, including farms with different breeds and housing systems. The housing systems included cage housing (n = 2), aviary housing (n = 2), floor housing without free-range access (n = 12), and free-range housing (n = 7). The age and flock size varied from 24 to 80 weeks of age and 5,800 to 60,000 chickens, respectively. All farms had a history of decreased egg production, diarrhea, and/or increased feed conversion. Single samples were collected from three to six chickens from the first six flocks, and then single samples were taken from the next 17 flocks. The submitted chickens were between 24 and 80 weeks of age.

Another 30 samples were collected from live birds submitted from two other farms with epidemiological links (farms 24 and 25). The samples from farm 24 were derived from 1, 4, and 17 chickens collected at 24, 48, and 56 weeks of age, respectively, while the samples from farm 25 were from 8 chickens of 50 weeks of age. On farm 24, there was reduced egg production and eggshell quality and slightly increased mortality (0.15%). Additionally, there was an above-average number of eggs with fecal staining of the eggshells due to wet feces. Egg production and eggshell quality on farm 25 also were decreased. Both farms were situated in Germany just across the Dutch borders (1 to 2 km) but were owned by a Dutch poultry farmer. They had the same caretaker and well for drinking water and were located 500 m from each other. On both farms, brown-layer hens of the same breed were housed in an aviary system with a free-range area. The free-range areas of the two farms were adjacent to each other. The farms housed 25,452 and 20,971 chickens, respectively. The flocks were reared at different farms and had different origins. Fattening pigs were housed within 300 m of both farms, while a swamp with waterfowl was present within 800 m of both farms.

IFAT. A routine diagnostic IFAT for Brachyspira spp. was performed on a smear of the contents of one cecum from each of the sampled chickens. The other cecum was kept in sterile water and was used for Brachyspira culture within 24 h if the IFAT was positive. The general method for IFAT was carried out as described previously (20). Briefly, smears on glass slides were air dried and fixed in acetone for 5 min and then were incubated at 37°C for 30 min with a unabsorbed Brachyspira-specific antiserum raised in a rabbit by repeated intramuscular injection with a formalinized bacterin produced from a Dutch B. hyodysenteriae strain (CIDC, Lelystad, The Netherlands). The serum had been shown to cross-react with other Brachyspira spp. Subsequently, the smears were subjected to three 2-min washes in phosphate-buffered saline (PBS), incubated for 30 to 45 min with goat anti-rabbit fluorescein isothiocyanate-labeled conjugate (Nordic, Tilburg, The Netherlands), and again subjected to three 2-min washes in PBS. The slides were dried and examined for positive apple-green fluorescent spirochetes using a UV fluorescence microscope (DM2000; Leica Microsystems) at x100 to x400 magnification. Negative and positive control samples were examined with each batch of slides.

Spirochete culture. Cecal contents were stirred with a sterile cotton-tipped swab that was used to inoculate two selective Trypticase soy agar (TSA) plates (BBL Microbiology Systems, Cockeysville, MD). One plate was supplemented with spectinomycin (200 µg/ml), spiromycin (25 µg/ml), rifampin (12.5 µg/ml), vancomycin (6.25 µg/ml), colistin (6.25 µg/ml), 0.1% yeast extract (Oxoid, Basingstoke, United Kingdom), and 5% defibrinated ovine blood (22), and the other plate was supplemented with spectinomycin (400 µg/ml), vancomycin (25 µg/ml), colistin (25 µg/ml), and 5% defibrinated ovine blood (18). The reference strains B. hyodysenteriae ATCC 27146 and B. pilosicoli ATCC 51139 each were used as positive controls on duplicate plates. The plates were incubated in an anaerobic jar under H2 and CO2 generated using an anaerogen gaspak (Oxoid) for 4 to 7 days at 42°C. If spirochetal growth was suspected, a piece of agar was removed and used to inoculate an agar plate supplemented with 5% defibrinated sheep blood (SBA) (Biotrading, Meidrecht, The Netherlands), which subsequently was incubated anaerobically at 42°C for 2 to 3 days. The purity and the presence of spirochetes were examined by Gram staining. In the case of pure cultures, an agar fragment was used to subculture the isolate onto four SBA plates and one TSA plate (without antibiotics). One SBA plate was used to harvest the spirochetes in a peptone-glycerol medium that was stored at –80°C. Only pure cultures were used for biochemical typing. In cases for which a pure culture could not be obtained (after repeating the procedure twice), the culture was harvested directly from the SBA plate. A total of 73 culture-positive samples were stored frozen at –80°C.

Phenotypic characteristics. Selected phenotypic characteristics of pure primary isolates from the original samples, and of three secondary cultures from frozen samples from farm 24, were determined using the methods described by Hommez and others (15). The presence and extent of â-hemolysis was observed on the original SBA plate after it was further incubated for 2 days. Spirochetes from the TSA plates were tested for indole by the spot test, while those from three of the SBA plates were harvested and pooled for the determination of -galactosidase, -glucosidase, â-glucosidase, and hippurate activity. The biochemical identification of pure cultures was performed as described for porcine isolates by Hommez and others (15), but with the addition of data for "B. pulli" and B. alvinipulli (34, 40). The phenotypic definitions used to identify the species are shown in Table 1.
 

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