Rectally obtained fecal samples can be used for fecal occult blood testing in dogs, and fecal immunochemical tests do not detect canine or feline blood.

OBJECTIVE: The first objective was to determine if the sample collection method (naturally voided vs digital rectal examination collection) affected fecal occult blood test (FOBT) results. The second objective was to assess the ability of human fecal hemoglobin immunochemical tests to detect canine and feline blood. ANIMALS: 308 privately owned dogs, healthy and sick. METHODS: Guaiac FOBTs were performed on paired voided and rectally obtained canine fecal samples. The kappa statistic was used to assess agreement between the 2 collection methods, and a multivariate regression model was used to identify factors associated with a positive FOBT. Two fecal immunochemical tests (FITs; Hemosure One Step and OC-Light S) were tested with serially diluted human, canine, and feline blood. RESULTS: Voided and rectally obtained samples showed strong FOB-positivity agreement (k = 0.80), with 92.5% concordance and only 13/308 dogs negative on void but positive on rectal. Multivariate analysis showed dogs with gastrointestinal disease (P = .0008, rectal; P = .0001, void) were more likely and heavier dogs (P = .0037, rectal; P = .0022 void) were less likely to test FOBT positive. Health status, fasting status, NSAID use, and age were associated with FOBT results on univariate, but not multivariate, analysis. FITs did not detect canine or feline blood at any concentration while human blood performed as expected. CLINICAL RELEVANCE: Rectally obtained fecal samples can be reliably used for FOBTs. Human FITs may not be suitable for companion animals, but evaluation of other available tests is needed.

Common and specific genomic sequences of avian and human extraintestinal pathogenic Escherichia coli as determined by genomic subtractive hybridization.

BACKGROUND: Suppression subtractive hybridization (SSH) strategy was used with extraintestinal pathogenic Escherichia coli (EXPEC) that cause avian colibacillosis (avian pathogenic E. coli or APEC) and human urinary tract infections (uropathogenic E. coli or UPEC) to determine if they possessed genes that were host and/or niche specific. Both APEC and UPEC isolates were used as tester and driver strains in 4 different SSHs in order to obtain APEC- and UPEC-specific subtraction fragments (SFs). RESULTS: These procedures yielded a total of 136 tester-specific SFs of which 85 were APEC-derived and 51 were UPEC-derived. Most of the APEC-derived SFs were associated with plasmids; whereas, the majority of UPEC-derived sequences matched to the bacterial chromosome. We further determined the distribution of these tester-derived sequences in a collection of UPEC and APEC isolates using polymerase chain reaction techniques. Plasmid-borne, APEC-derived sequences (tsh, cvaB, traR, traC and sopB) were predominantly present in APEC, as compared to UPEC. Of the UPEC-derived SFs, those encoding hemolysin D and F1C major and minor fimbrial subunits were present only in UPEC. However, two UPEC-derived SFs that showed strong similarity to the uropathgenic-specific protein gene (usp) occurred in APEC, demonstrating that usp is not specific to UPEC. CONCLUSION: This study provides evidence of the genetic variability of ExPEC as well as genomic similarities between UPEC and APEC; it did not identify any single marker that would dictate host and/or niche specificity in APEC or UPEC. However, further studies on the genes that encode putative or hypothetical proteins might offer important insight into the pathogenesis of disease, as caused by these two ExPEC.

Complete DNA sequence, comparative genomics, and prevalence of an IncHI2 plasmid occurring among extraintestinal pathogenic Escherichia coli isolates.

We have sequenced a large plasmid that occurs among avian pathogenic Escherichia coli isolates. This plasmid, pAPEC-O1-R, is a 241,387-bp IncHI2 plasmid which is cotransmissible via bacterial conjugation with a ColBM virulence plasmid, encodes resistance to eight antimicrobial agents, and appears to occur at low rates among extraintestinal E. coli isolates.