In many species, the biosynthesis of vitamin D begins with exposure to UV light, wherein 7-dehydrocholesterol is transformed to previtamin D3. Factors that affect synthesis of vitamin D3 include quantity and quality of the UV light, coat, and skin pigmentation. Dogs and cats are unique from humans and many other species in that they lack the ability to synthesize vitamin D3 in the skin, likely because of high activity of 7-dehydrocholesterol-Δ7-reductase.1,2 For this reason, dogs and cats require dietary supplementation with vitamin D to meet nutritional
Chronic enteropathies are a heterogeneous group of gastrointestinal disorders characterized by gastrointestinal clinical signs that persist for at least 2 weeks. Depending on the study, chronic enteropathies and other diagnoses (eg, IBD) may include a variety of disorders and patient populations, and the inconsistent nomenclature can result in confusing information in the literature. Regardless, achieving a correct diagnosis and classification of chronic enteropathy is essential for proper nutritional management. The most important step in this process is eliminating the possibility of systemic disorders as well as ruling out several primary gastrointestinal diseases, all of which may be less responsive to
The environment of the GIT is composed of a diverse microbiome. On the basis of environmental, dietary, and genetic factors, the GIT environment develops from a sterile environment to one consisting primarily of anaerobes.1 During development of the microbiome and after the microbiome is stabilized, commensal and pathogenic microorganisms, along with their interactions, impact the overall microenvironment. The resultant steady-state microenvironment or alternations in steady state attributable to microbial organisms and their products (eg, pH or fatty acid production) interact with the host through the local immune system and enteroendocrine signaling. These local effects, which are influenced by
To investigate the prevalence of Escherichia coli contamination and E coli virulence gene signatures consistent with known E coli pathotypes in commercially available conventional diets and raw-meat–based diets (RMBDs).
40 diets in total (19 conventionally cooked kibble or canned diets and 21 RMBDs) obtained from retail stores or online distributors.
Each diet was cultured for E coli contamination in 3 separate container locations using standard microbiological techniques. Further characterization of E coli isolates was performed by polymerase chain reaction-based pathotype and virulence gene analysis.
Conventional diets were negative in all culture based testing. In RMBDs, bacterial contamination was similar to previous reports in the veterinary literature, with 66% (14/21) of the RMBDs having positive cultures for E coli. Among the 191 confirmed E coli isolates from these diets, 31.9% (61/191) were positive for virulence genes. Categorized by pathotype, isolates presumptively belonging to the neonatal meningitis E coli pathotype (15.7% [30/191]) were the most common, followed by enterohemorrhagic E coli (10.5% [20/191]), enteropathogenic E coli (5.8% [11/191]), uropathogenic E coli (2.1% [4/191]), and diffusely adherent E coli (1.6% [3/191]).
The results of this study reaffirmed the bacteriologic risks previously associated with RMBDs. Furthermore, potential zoonotic concerns associated with identified pathotypes in these diets may have significant consequences for owners in the animals’ home environment. Potential risk associated with bacterial contamination should be addressed in animals fed RMBDs.
OBJECTIVE To measure effects of oral Akkermansia muciniphila administration on systemic markers of gastrointestinal permeability and epithelial damage following antimicrobial administration in dogs.
ANIMALS 8 healthy adult dogs.
PROCEDURES Dogs were randomly assigned to receive either A muciniphila (109 cells/kg; n = 4) or vehicle (PBS solution; 4) for 6 days following metronidazole administration (12.5 mg/kg, PO, q 12 h for 7 d). After a 20-day washout period, the same dogs received the alternate treatment. After another washout period, experiments were repeated with amoxicillin-clavulanate (13.5 mg/kg, PO, q 12 h) instead of metronidazole. Fecal consistency was scored, a quantitative real-time PCR assay for A muciniphila in feces was performed, and plasma concentrations of cytokeratin-18, lipopolysaccharide, and glucagon-like peptides were measured by ELISA before (T0) and after (T1) antimicrobial administration and after administration of A muciniphila or vehicle (T2).
RESULTSA muciniphila was detected in feces in 7 of 8 dogs after A muciniphila treatment at T2 (3/4 experiments) but not at T0 or T1. After metronidazole administration, mean change in plasma cytokeratin-18 concentration from T1 to T2 was significantly lower with vehicle than with A muciniphila treatment (−0.27 vs 2.4 ng/mL). Mean cytokeratin-18 concentration was lower at T1 than at T0 with amoxicillin-clavulanate. No other significant biomarker concentration changes were detected. Probiotic administration was not associated with changes in fecal scores. No adverse effects were attributed to A muciniphila treatment.
CONCLUSIONS AND CLINICAL RELEVANCE Detection of A muciniphila in feces suggested successful gastrointestinal transit following oral supplementation in dogs. Plasma cytokeratin-18 alterations suggested an effect on gastrointestinal epithelium. Further study is needed to investigate effects in dogs with naturally occurring gastrointestinal disease.
To characterize uropathogenic Escherichia coli (UPEC) in cases of clinical feline urinary tract infection (UTI) and subclinical bacteriuria and investigate the in vitro effects of E coli strain Nissle 1917 on isolate growth.
40 cats with positive E coli culture results for urine collected during routine evaluation.
Characterization of UPEC isolates was performed by PCR-based phylotype analysis and serotyping. Nissle 1917 effects on growth inhibition and competitive overgrowth against UPEC isolates were evaluated in vitro using a plate-based competition assay.
Feline phylogroups were similar to previous human and feline UPEC studies, with most of the isolates belonging to phylogroup A (42.5%), B2 (37.5%), and D (15.0%). Fifty-two percent of isolates were found to be resistant to antimicrobials, with 19% of these being multidrug resistant (MDR). Nissle 1917 adversely affected the growth of 82.5% of all isolates and 100% of MDR isolates in vitro. The median zone of inhibition was 3.33 mm (range, 1.67 to 10.67 mm). Thirteen isolates were affected via competitive overgrowth and 20 via growth inhibition.
UPEC isolates from cats were similar in phylogroup analysis to human and dog isolates. The in vitro effects of Nissle 1917 on UPEC warrant additional studies to determine if similar results can be duplicated in vivo.