Pilot study to evaluate the effect of oral supplementation of Enterococcus faecium SF68 on cats with latent feline herpesvirus 1

Insights into the interplay between gut microbiota and lipid metabolism in the obesity management of canines and felines

Obesity is a prevalent chronic disease that has significant negative impacts on humans and our companion animals, including dogs and cats. Obesity occurs with multiple comorbidities, such as diabetes, hypertension, heart disease and osteoarthritis in dogs and cats. A direct link between lipid metabolism dysregulation and obesity-associated diseases has been implicated. However, the understanding of such pathophysiology in companion animals is limited. This review aims to address the role of lipid metabolism in various metabolic disorders associated with obesity, emphasizing the involvement of the gut microbiota. Furthermore, we also discuss the management of obesity, including approaches like nutritional interventions, thus providing novel insights into obesity prevention and treatment for canines and felines.

Probiotics and Cat Health: A Review of Progress and Prospects

Cats are increasingly favored as companion animals; their health has drawn widespread attention. Given the continuous improvements in the required living standards of both humans and animals, inflammatory bowel disease, allergies, diarrhea, constipation, periodontal disease, obesity, diabetes, and other health issues have become recognized as valid pet problems. Antibiotics are commonly used to treat pet diseases, greatly improving animal health. However, antibiotic abuse is common, especially when seeking to treat bacterial infections. Probiotics are beneficial microorganisms that may be directly ingested in food or as feed additives; they improve the intestinal microflora balance, enhance immunity, and ensure healthy growth. However, cat data are usually inferred from reports on dogs or humans; cat research remains preliminary in nature. Therefore, we here describe the current understanding of how probiotics improve cat health, facilitating the further development and application of probiotics for cats.

Effect of a Multistrain Probiotic on Feline Gut Health through the Fecal Microbiota and Its Metabolite SCFAs

With the increasing awareness of raising pets following scientific methods, people are becoming increasingly more interested in the nutrition and health of pets, especially their intestinal health, which has become a research hotspot. Both Saccharomyces boulardii and Pediococcus acidilactici are probiotics with strong probiotic properties that can maintain the balance of intestinal flora. However, the role of Saccharomyces boulardii and Pediococcus acidilactici in felines has not been comprehensively studied to date. The aim of this study is to investigate the effect of multistrain probiotics consisting of Saccharomyces boulardii and Pediococcus acidilactici on the gut health of felines by modulating gut microbes and the production of metabolite SCFAs. The results show that the multistrain probiotic did not alter the intestinal microbial diversity and structure of short-haired domestic cats, promoted the colonization of beneficial bacteria, increased the levels of microbiota-derived SCFAs and fecal antioxidants, and reduced the levels of fecal inflammatory markers. In conclusion, the use of a multistrain probiotic in healthy, short-haired domestic cats can promote gut health by modulating gut microbes, improving microbiota-derived SCFA production, reducing inflammatory conditions, and improving antioxidant status. These results provide new insights for further exploration of the role of probiotics in the gut microbiome of cats.

Randomized placebo-controlled trial of feline-origin Enterococcus hirae probiotic effects on preventative health and fecal microbiota composition of fostered shelter kittens

Introduction

Diarrhea is the second most common cause of mortality in shelter kittens. Studies examining prevention strategies in this population are lacking. Probiotics are of particular interest but studies in cats are largely limited to healthy adults or those with induced disease. Only one study in domestic cats describes the use of host-derived bacteria as a probiotic. We previously identified Enterococcus hirae as a dominant species colonizing the small intestinal mucosa in healthy shelter kittens. Oral administration of a probiotic formulation of kitten-origin E. hirae (strain 1002-2) mitigated the increase in intestinal permeability and fecal water loss resulting from experimental enteropathogenic E. coli infection in purpose-bred kittens. Based on these findings, we hypothesized that administration of kitten-origin E. hirae to weaned fostered shelter kittens could provide a measurable preventative health benefit.

Methods

We conducted a randomized, placebo-controlled, blinded clinical trial to determine the impact of a freeze-dried E. hirae probiotic on body weight gain, incidence of diarrhea, carriage of potential diarrheal pathogens, and composition of the intestinal microbiota in weaned fostered shelter kittens.

Results

One-hundred thirty kittens completed the study. Fifty-eight kittens received the probiotic and 72 received the placebo. There were no significant differences in age, weight upon initiation of the study, number of days in the study, average daily gain in body weight, or weight at completion of the study. Kittens treated with E. hirae were 3.4 times less likely to develop diarrhea compared to kittens treated with placebo (odds ratio = 0.294, 95% CI 0.109-0.792, p = 0.022). A significant impact of E. hirae was not observed on the presence or abundance of 30 different bacterial, viral, protozoal, fungal, algal, and parasitic agents in feces examined by qPCR. With exception to a decrease in Megamonas, administration of the E. hirae probiotic did not alter the predominant bacterial phyla present in feces based on 16S rRNA gene amplicon sequencing.

Discussion

Decreased incidence of diarrhea associated with preventative administration of E. hirae to foster kittens supports a rationale for use of E. hirae for disease prevention in this young population at high risk for intestinal disease though additional studies are warranted.

Perspectives and Advances in Probiotics and the Gut Microbiome in Companion Animals

As the number of households that raise dogs and cats is increasing, there is growing interest in animal health. The gut plays an important role in animal health. In particular, the microbiome in the gut is known to affect both the absorption and metabolism of nutrients and the protective functions of the host. Using probiotics on pets has beneficial effects, such as modulating the immune system, helping to reduce stress, protecting against pathogenic bacteria and developing growth performance. The goals of this review are to summarize the relationship between probiotics/the gut microbiome and animal health, to feature technology used for identifying the diversity of microbiota composition of canine and feline microbiota, and to discuss recent reports on probiotics in canines and felines and the safety issues associated with probiotics and the gut microbiome in companion animals.

The Interaction Between Viruses and Intestinal Microbiota: A Review

As the main pathogen threatening human and animal health, viruses can affect the immunity and metabolism of bodies. There are innate microbial barriers in the digestive tract of the body to preserve the homeostasis of the animal body, which directly or indirectly influences the host defence against viral infection. Understanding the interaction between viruses and intestinal microbiota or probiotics is helpful to study the pathogenesis of diseases. Here, we review recent studies on the interaction mechanism between intestinal microbiota and viruses. The interaction can be divided into two aspects: inhibition of viral infection by microbiota and promotion of viral infection by microbiota. The treatment of viral infection by probiotics is summarized.

Risks associated with enterococci as probiotics

Probiotics are naturally occurring microorganisms that confer health benefits by altering host commensal microbiota, modulating immunity, enhancing intestinal barrier function, or altering pain perception. Enterococci are human and animal intestinal commensals that are used as probiotics and in food production. These microorganisms, however, express many virulence traits including cytolysin, proteases, aggregation substance, capsular polysaccharide, enterococcal surface protein, biofilm formation, extracellular superoxide, intestinal translocation, and resistance to innate immunity that can lead to serious hospital-acquired infections. In addition, enterococci are facile in acquiring antibiotic resistance genes to many clinically important antibiotics encoded on a wide variety of conjugative plasmids, transposons, and bacteriophages. The pathogenicity and disease burden caused by enterococci render them poor choices as probiotics. No large, randomized, placebo-controlled clinical trials have demonstrated the safety and efficacy of any enterococcal probiotic. As a result, no enterococcal probiotic has been approved by the United States Food and Drug Administration for the treatment, cure, or amelioration of human disease. In 2007, the European Food Safety Authority concluded that enterococci do not meet the standard for "Qualified Presumption of Safety". Enterococcal strains used or proposed for use as probiotics should be carefully screened for efficacy and safety.

Effect of a Pheromone on Stress-Associated Reactivation of Feline Herpesvirus-1 in Experimentally Inoculated Kittens

Background

Stress contributes to reactivation of feline herpesvirus‐1 (FHV‐1). The usage of pheromones to decrease stress in FHV‐1 experimentally inoculated kittens has not previously been investigated.

Hypothesis/Objectives

To determine whether a feline pheromone would lessen stress, resulting in decreased recurrence of FHV‐1‐associated illness in kittens.

Animals

Twelve 5‐month‐old, purpose‐bred kittens.

Methods

Randomized, double‐blind, placebo‐controlled clinical trial. Kittens previously infected with the same dose of FHV‐1 were randomized into 2 separate but identical group rooms. After a 2‐week equilibration period, a diffuser containing either the pheromone or placebo was placed in each of the rooms, and the kittens acclimated for an additional 2 weeks. Every 2 weeks thereafter, for the 8‐week study period, housing was alternated between kennel‐ and group housing. Blinded observers applied a standardized clinical and behavioral scoring rubric daily. After each 2‐week period, serum cortisol concentrations and quantitative PCR for FHV‐1 and glyceraldehyde 3‐phosphate dehydrogenase (GAPDH) ratios were evaluated. Clinical, behavioral, and laboratory test results were compared between groups within individual and combined study periods.

Results

Sneezing occurred more frequently in the placebo group during individual (P = 0.006) and combined study periods (P = 0.001). Sleep at the end of observation periods occurred more frequently in the pheromone group during individual (P = 0.006) and combined study periods (P < 0.001).

Conclusions and Clinical Importance

The findings suggest that the pheromone decreased stress, and the decrease in stress response may have resulted in decreased sneezing associated with FHV‐1.

Evaluation of Metronidazole With and Without Enterococcus Faecium SF68 in Shelter Dogs With Diarrhea

Diarrhea is common in shelter dogs and nonspecific therapies like therapeutic diets, probiotics, and drugs with activity against Giardia spp. or enteric bacteria are commonly prescribed empirically. All dogs in this study were administered metronidazole, fed a standardized diet, and randomized to either receive a commercially available probiotic (Purina^® Pro Plan^® Veterinary Diets; FortiFlora^® Probiotic Supplement, FortiFlora, Nestle Purina PetCare, St Louis, MO) or a placebo which was the commercial product without the probiotic for 7 days. A fecal score was assigned to each stool passed during the study by masked individuals. Fecal samples were evaluated for select enteric agents including nematodes, Giardia spp., Cryptosporidium spp., and Clostridium perfringens enterotoxin before and at the end of the treatment period. There were no differences between groups in regard to parasite prevalence. By day 7, a normal stool (<5) was detected in 37.5% of the dogs administered metronidazole and 68.8% of the dogs administered dual therapy, but the result was not significant (P = .1556). The percentages of days with normal stools were significantly higher (P = .0496) for dogs administered dual therapy 65.6%) when compared to those administered metronidazole alone (46.9%). Giardia cysts were eliminated and diarrhea resolved in both dogs that were infected in the SF68 group. In contrast, of the 7 Giardia positive dogs in the placebo group, 6 (85.7%) were still positive for Giardia cysts on day 7, and 4 of those dogs still had diarrhea on day 7. Addition of SF68 to this protocol of metronidazole and a standardized diet appeared to enhance clinical responses in shelter dogs with diarrhea.

Effect of Enterococcus Faecium Strain SF68 on Gastrointestinal Signs and Fecal Microbiome in Cats Administered Amoxicillin-Clavulanate

Some cats develop vomiting or diarrhea during administration of some antibiotics such as amoxicillin-clavulanate but how often this occurs and the severity of disease is generally unknown. In people, one of the accepted indications for the use of probiotics is to attempt and lessen antibiotic-associated diarrhea. Enterococcus faecium strain SF68 (SF68; Purina^® ProPlan^® Veterinary Diets; FortiFlora™ Probiotic Supplement) is a commercially available probiotic available in many countries that has been shown to lessen diarrhea rates in cats housed in animal shelters. The objectives of this study were to describe the gastrointestinal abnormalities (clinical and microbiome) associated with the administration of amoxicillin-clavulanate to cats and to determine whether feeding SF68 could ameliorate those abnormalities. Laboratory reared domestic cats were administered amoxicillin-clavulanate for 7 days with or without SF68 for 14 days and monitored for vomiting and diarrhea and for changes in the gastrointestinal microbiome before and after antibiotic administration. Fecal scores > 5 on a 7-point scale were detected in 9 of 13 cats (69.2%) fed SF68 compared to 12 of 14 cats fed the placebo (85.7%). Fecal scores of 7 were only detected in the placebo group and when total diarrhea scores were compared between groups for days 1-11, the cats fed SF68 were statistically lower (P = 0.0058). Administration of amoxicillin-clavulanate led to decreased microbiome diversity, but differences between cats fed SF68 or the placebo were not detected. The results show administering amoxicillin-clavulanate orally to cats commonly induces diarrhea and alters the gastrointestinal microbiome, and that feeding the probiotic SF68 can lessen some associated clinical abnormalities.

Oral Probiotics Alter Healthy Feline Respiratory Microbiota

Probiotics have been advocated as a novel therapeutic approach to respiratory disease, but knowledge of how oral administration of probiotics influences the respiratory microbiota is needed. Using 16S rRNA amplicon sequencing of bacterial DNA our objective was to determine whether oral probiotics changed the composition of the upper and lower airway, rectal, and blood microbiota. We hypothesized that oral probiotics would modulate the respiratory microbiota in healthy cats, demonstrated by the detection and/or increased relative abundance of the probiotic bacterial species and altered composition of the microbial population in the respiratory tract. Six healthy young research cats had oropharyngeal (OP), bronchoalveolar lavage fluid (BALF), rectal, and blood samples collected at baseline and 4 weeks after receiving oral probiotics. 16S rRNA gene amplicon libraries were sequenced, and coverage, richness, and relative abundance of representative operational taxonomic units (OTUs) were determined. Hierarchical and principal component analyses (PCA) demonstrated relatedness of samples. Mean microbial richness significantly increased only in the upper and lower airways. The number of probiotic OTUs (out of 5 total) that significantly increased in relative abundance vs. baseline was 5 in OP, 3 in BAL and 2 in feces. Using hierarchical clustering, BALF and blood samples grouped together after probiotic administration, and PERMANOVA supported that these two sites underwent significant changes in microbial composition. PERMANOVA revealed that OP and rectal samples had microbial population compositions that did not significantly change. These findings were visualized via PCA, which revealed distinct microbiomes in each site; samples clustered more tightly at baseline and had more variation after probiotic administration. This is the first study describing the effect of oral probiotics on the respiratory microbiota via detection of probiotic species in the airways. Finding bacterial species present in the oral probiotics in the upper and lower airways provides pilot data suggesting that oral probiotics could serve as a tool to target dysbiosis occurring in inflammatory airway diseases such as feline asthma, a disease in which cats serve as an important comparative and translational model for humans.

A review of antiviral drugs and other compounds with activity against feline herpesvirus type 1

Feline herpesvirus type 1 (FHV-1) is a common and important cause of ocular surface disease, dermatitis, respiratory disease, and potentially intraocular disease in cats. Many antiviral drugs developed for the treatment of humans infected with herpesviruses have been used to treat cats infected with FHV-1. Translational use of drugs in this manner ideally requires methodical investigation of their in vitro efficacy against FHV-1 followed by pharmacokinetic and safety trials in normal cats. Subsequently, placebo-controlled efficacy studies in experimentally inoculated animals should be performed followed, finally, by carefully designed and monitored clinical trials in client-owned animals. This review is intended to provide a concise overview of the available literature regarding the efficacy of antiviral drugs and other compounds with proven or putative activity against FHV-1, as well as a discussion of their safety in cats.

Effect of short-term probiotic Enterococcus faecium SF68 dietary supplementation in overweight and obese cats without comorbidities

Obesity in cats is associated with metabolic abnormalities and increased susceptibility to diseases such as diabetes mellitus. Studies in mouse models and human beings have shown that probiotics can reduce food intake, promote weight loss and improve metabolic profile. Studies assessing the effects of probiotics on these same parameters are absent in cats. Therefore, the aim of this study was to determine if probiotic Enterococcus faecium strain SF68 dietary supplementation reduces food intake, promotes weight loss and improves metabolic profile in overweight and obese cats without comorbidities. Twenty overweight and obese specific pathogen-free cats without comorbidities were acclimatised to a dry diet for four weeks. After exclusion of four cats for unrelated reasons, eight cats received a daily oral probiotic for eight weeks and eight control cats received no probiotic. All cats were fed ad libitum with food intake measured daily and bodyweight weekly. Blood was collected at three time points: after four weeks of acclimatisation to the diet, after eight weeks of intervention and after six weeks of washout for measurement of glucose, triglyceride, cholesterol, fructosamine, insulin, leptin, total adiponectin and deuterium oxide for body composition. There were no differences in food intake, metabolic parameters and body composition between the probiotic and control groups after eight weeks of intervention and six weeks of washout (P≥0.050). Short-term use of E faecium SF68 dietary supplementation had no significant effect on food intake, bodyweight, body composition or metabolic parameters in overweight and obese specific pathogen-free cats without comorbidities.

Pediatric nutrition

This article discusses pediatric nutrition in puppies and kittens. Supplementation of basic nutrients such as fat, protein, minerals, vitamins, and essential fatty acids of the bitch is essential for the proper growth and development of puppies during the lactation period. Milk replacers are compared for use in puppies and kittens. Supplements such as colostrum and probiotics for promotion of a healthy immune system and prevention or treatment of stress-induced and weaning diarrhea are also discussed.

Effect of a multi-species synbiotic formulation on fecal bacterial microbiota of healthy cats and dogs as evaluated by pyrosequencing

The effect of a multi-species synbiotic on the fecal microbiota of healthy cats (n = 12) and dogs (n = 12) was evaluated. The synbiotic (containing 5 × 10(9)  CFU of a mixture of seven probiotic strains, and a blend of fructooligosaccharides and arabinogalactans) was administered daily for 21 days. Fecal and serum samples were collected before, during, and up to 3 weeks after administration. Changes in the fecal microbiota were analyzed using denaturing gradient gel electrophoresis, 16S rRNA gene libraries, quantitative real-time PCR, and 16S rRNA gene 454-pyrosequencing. Probiotic species were detectable in 10/12 dogs and 11/12 cats during product administration. Abundances of Enterococcus and Streptococcus spp. were significantly increased in at least one time point during administration, and returned to baseline abundance after treatment was discontinued. No changes in the major bacterial phyla were identified on 454-pyrosequencing. No adverse gastrointestinal effects were recorded and no significant changes in gastrointestinal function or immune markers were observed during the study period. This study shows that while the ingestion of probiotics and prebiotics does not appear to alter the predominant bacterial phyla present in feces, supplementation with the investigated synbiotic leads to an increased abundance of probiotic bacteria in the feces of healthy cats and dogs.

Results of molecular diagnostic assays targeting feline herpesvirus-1 and feline calicivirus in adult cats administered modified live vaccines

In this pilot study, 12 adult, gang-housed cats that were known to be previously exposed (n=12) to feline herpesvirus-1 (FHV-1) and/or vaccinated against (n=2) feline calicivirus (FCV) and FHV-1 were randomly assigned to one of two groups of six cats each. Nasal and pharyngeal samples were collected from each cat on days -7, -3, and 0 prior to vaccination and on days 3, 7, 10, 14, 17, 21, and 28 after vaccination with an FHV-1, FCV, and panleukopenia (FVRCP) vaccine developed for intranasal (six cats) or parenteral (six cats) use. FHV-1 DNA was amplified from 1/12 cats (1/69 samples; 1.4%) prior to vaccination and 2/12 cats after vaccination (2/154 samples; 1.3%). FCV RNA was amplified from 2/12 cats (2/69 samples; 2.9%) prior to vaccination and 7/12 cats (12/154 samples; 7.8%) after vaccination. Positive molecular diagnostic assay results for FHV-1 and FCV were uncommon prior to or after vaccination in these cats.

Effect of the probiotic Enterococcus faecium SF68 on presence of diarrhea in cats and dogs housed in an animal shelter

BACKGROUND

Beneficial effects of probiotics have never been analyzed in an animal shelter.

HYPOTHESIS

Dogs and cats housed in an animal shelter and administered a probiotic are less likely to have diarrhea of ≥2 days duration than untreated controls.

ANIMALS

Two hundred and seventeen cats and 182 dogs.

METHODS

Double blinded and placebo controlled. Shelter dogs and cats were housed in 2 separate rooms for each species. For 4 weeks, animals in 1 room for each species was fed Enterococcus faecium SF68 while animals in the other room were fed a placebo. After a 1-week washout period, the treatments by room were switched and the study continued an additional 4 weeks. A standardized fecal score system was applied to feces from each animal every day by a blinded individual. Feces of animals with and without diarrhea were evaluated for enteric parasites. Data were analyzed by a generalized linear mixed model using a binomial distribution with treatment being a fixed effect and the room being a random effect.

RESULTS

The percentage of cats with diarrhea ≥2 days was significantly lower (P = .0297) in the probiotic group (7.4%) when compared with the placebo group (20.7%). Statistical differences between groups of dogs were not detected but diarrhea was uncommon in both groups of dogs during the study.

CONCLUSION AND CLINICAL IMPORTANCE

Cats fed SF68 had fewer episodes of diarrhea of ≥2 days when compared with controls suggests the probiotic may have beneficial effects on the gastrointestinal tract.

Feline herpesvirus-1: ocular manifestations, diagnosis and treatment options

PRACTICAL RELEVANCE

Feline herpesvirus-1 (FHV-1) is a major cause of feline morbidity. Following exposure to the virus, virtually all cats become persistently infected and many of these will develop recrudescent disease on one or more occasions during their lifetime. Acute ocular herpetic disease manifests as conjunctivitis, corneal ulceration and keratitis, and can be severe and painful. Repeated bouts of recrudescent ocular disease can lead to progressive corneal pathology that can be ultimately blinding in affected cats.

GLOBAL IMPORTANCE

FHV-1 has a worldwide distribution, with reported exposure rates in some cat populations of up to 97%. As such it is a significant cause of clinical disease in the global cat population.

PATIENT GROUP

Young and adolescent cats are most at risk of acute primary disease, and the vast majority of these will become persistently infected. Around half of all persistently infected cats will shed virus at some stage in their life and these may develop recrudescent ocular disease.

CLINICAL CHALLENGES

Treatment of FHV-1 ocular disease is challenging. Antiviral medications may be expensive, and require good owner and patient compliance. Clinical responses in patients can be variable. Selecting the appropriate therapeutic approach requires good clinical judgement, with assessment of factors such as severity and stage of clinical disease, patient and owner compliance, and financial considerations.

EVIDENCE BASE

Although a wide range of antiviral treatments is available, few have been tested in controlled clinical trials. Therapeutic decisions are, therefore, often based on results of in vitro studies, case-based reports and anecdote. Large, masked, controlled clinical trials are required in order to determine the efficacy of the antiviral drugs currently available to treat FHV-1.