Human Health Implications of Salmonella-Contaminated Natural Pet Treats and Raw Pet Food

Outbreak of multidrug-resistant Salmonella infections in people linked to pig ear pet treats, United States, 2015-2019: results of a multistate investigation

Background

International distribution of contaminated foods can be a source of Salmonella infections in people and can contribute to the spread of antimicrobial-resistant bacteria across countries. We report an investigation led by the United States Centers for Disease Control and Prevention, the Food and Drug Administration (FDA), and state governmental officials into a multistate outbreak of salmonellosis linked to pig ear pet treats.

Methods

Pig ear treats and companion dogs were tested for Salmonella by state officials and the FDA. Products were traced back to the country of origin when possible. Cases were defined as outbreak illnesses in people associated with one of seven Salmonella serotypes genetically related to samples from pig ear pet treats, with isolation dates from June 2015 to September 2019. Whole genome sequencing (WGS) of isolates was used to predict antimicrobial resistance.

Findings

The outbreak included 154 human cases in 34 states. Of these, 107 of 122 (88%) patients reported dog contact, and 65 of 97 (67%) reported contact with pig ear pet treats. Salmonella was isolated from 137 pig ear treats, including some imported from Argentina, Brazil, and Colombia, and from four dogs. WGS predicted 77% (105/137) of human and 43% (58/135) of pig ear treat isolates were resistant to ≥3 antimicrobial classes.

Interpretation

This was the first documented United States multistate outbreak of Salmonella infections linked to pig ear pet treats. This multidrug-resistant outbreak highlights the interconnectedness of human health and companion animal ownership and the need for zoonotic pathogen surveillance to prevent human illness resulting from internationally transported pet food products.

Funding

Animal Feed Regulatory Program Standards award. Animal and product testing conducted by FDA Vet-LIRN was funded by Vet-LIRN infrastructure grants (PAR-22-063).

Reporting perceived capability, motivations, and barriers to reducing treat feeding amongst dog and cat caregivers

Obesity remains a significant concern for dogs and cats, and reducing or eliminating treats is commonly recommended as a strategy for weight management. Caregivers can struggle with adherence to such dietary recommendations. Previous research suggests caregivers are reluctant to reduce treats but there is limited understanding of the underlying factors contributing to these behaviours and decisions. The objective of this study was to explore caregivers' motivations and barriers to reducing treat feeding, and their reported capability to do so. An online questionnaire including multiple choice and Likert scale questions was disseminated to dog and cat caregivers (n=1053) primarily from Canada and the USA from September to November 2021. Caregivers commonly expressed a wide range of motivations to reduce treat feeding with their pet, though barriers to reducing treat feeding were less defined. Changing their pet's routine was a reported barrier by more than 30% of respondents and was predictive of caregivers finding reducing treat giving to be difficult (OR=1.67, p=0.017). Results from multivariable logistic regression also revealed that caregivers who consider their companion animal to be obese as more likely to perceive reducing treats to be difficult. The results highlight the role of treats in the relationship and routine of caregivers' and their pets, and the importance of considering the individualised needs and circumstance of the caregiver and pet in veterinary discussions surrounding reducing treat feeding. Identifying these perspectives can improve self-efficacy with veterinary nutrition recommendations surrounding treats.

Fecal microbiota composition, serum metabolomics, and markers of inflammation in dogs fed a raw meat-based diet compared to those on a kibble diet

Introduction

Despite the potential health risks associated with feeding raw and non-traditional diets, the use of these diets in dogs is increasing, yet the health outcomes associated with these diets is not well understood. This study investigates the effect of feeding dogs a kibble or raw meat-based diets on fecal microbiota composition, serum metabolomics and inflammatory markers.

Methods

Clinically healthy dogs with a history of consuming either kibble (KD, n = 27) or raw meat-based diets (RMBD, n = 28) for more than 1 year were enrolled. Dogs were fed a standardized diet of either a single brand of KD or RMBD for 28 days. Serum and fecal samples were collected for analysis of microbiota, metabolomics, and inflammatory markers. Multiple regression analysis was performed for each of the metabolites and inflammatory markers, with feed group, age and BCS included as independent variables.

Results

The fecal microbiota composition differed between the KD and RMBD groups. Beta-diversity and some indices of alpha-diversity (i.e., Shannon and Simpson) were different between the two diet groups. Sixty- three serum metabolites differed between KD and RMBD-fed dogs with the majority reflecting the differences in macronutrient composition of the two diets.Fecal IAP, IgG and IgA were significantly higher in RMBD dogs compared to KD dogs, while systemic markers of inflammation, including serum c-reactive protein (CRP), galectin, secretory receptor of advanced glycation end-products (sRAGE), haptoglobin, and serum IgG were similar in dogs fed either diet.

Discussion

Diet composition significantly affected fecal microbiota composition and metabolome. Although it had a potentially beneficial effect on local inflammatory markers, feeding RMBD had no impact on systemic inflammation. The influence of these changes on long term health outcomes provides an area for future study.

Microflora, Contents of Polyamines, Biogenic Amines, and TVB-N in Bovine Offal and Game Meat for the Raw-Feeding of Adult Dogs

Microflora and contents of biogenic amines/polyamines and total volatile basic nitrogen (TVB-N) in 99 samples of bovine offal (red offal, n = 41 and other offal and mixes, n = 45) and wild game meat (n = 13) for raw meat-based diets (RMBD) for dogs were analyzed. Samples were bought in 11 local pet food shops and in one game-handling establishment in Austria (Lower Austria, Styria, and Vienna) in September and October 2022. Median contents (first and third quartiles in brackets) of cadaverine, histamine, tyramine, spermidine, and spermine were 20.7 [16.7; 28.6]; 25.4 [17.1; 47.2]; 18.9 [13.6; 38.9]; 15.2 [11.2; 21.2]; and 41.9 [<limit of detection; 64.5] mg/kg wet weight, respectively. The sum of putrescine + cadaverine + histamine + tyramine was >50 mg/kg in 85.9% of samples, indicating the use of low-quality ingredients or inappropriate storage conditions. However, only 10.1% of samples were determined to be not compliant with a maximum amine content proposed for pet food. Median contents of the total aerobic bacteria counts (TACs), Pseudomonas, and Enterobacteriaceae were 7.4 [6.4; 8.0]; 6.5 [5.5; 7.7]; and 4.8 [3.9; 5.6] log CFU/g, respectively, with significantly lower counts in red offal RMBD (p < 0.05). TVB-N exceeded 150 mg/kg in 87.9% of samples. The TACs and Enterobacteriaceae numbers in red offal RMBD were comparable to those in food-grade red offal after 6 days of aerobic storage at 7 °C, i.e., temperatures higher than required for food-grade offal, but acceptable for animal by-products intended for RMBD production. In 80.8% of samples, numbers of Enterobacteriaceae exceeded the EU legal limit. From 12 of these samples, Salmonellae was able to be isolated, with counts from 0.03 MPN/g to 110 MPN/g. Salmonella enterica ser. Montevideo (n = 3), and S. enterica ser. Give and S. enterica ssp. Diarizonae (n = 2 each) were the most frequently isolated, while Listeria monocytogenes was rarely recovered (2%). Whilst exposure of humans handling such pet food can be reduced by hygiene precautions, the risk remains that dogs can acquire a feed-borne salmonellosis and shed the pathogen.

Application of encapsulated and dry-plated food acidulants to control Salmonella enterica in raw meat-based diets for dogs

There is an increasing demand for raw meat-based diets (RMBDs) for dogs, but these foods cannot be heat-pasteurized. Thus, the objective of this study was to evaluate the antimicrobial efficacy of encapsulated and dry-plated glucono delta lactone (GDL), citric acid (CA), and lactic acid (LA) when challenged against Salmonella enterica inoculated in a model raw meat-based diet (RMBDs) for dogs. Nutritionally complete, raw diets were formulated with different levels (1.0, 2.0 and 3.0% (w/w)) of both encapsulated and dry-plated GDL, CA, and LA with both the positive (PC) and the negative controls (NC) without acidulants. The diets were formed into patties of ∼100 g and inoculated with 3-cocktail mixtures of Salmonella enterica serovars, excluding the NC to achieve a final concentration of ∼6.0 Log CFU/patty. Microbial analyses were performed on the inoculated diets and survivors of S. enterica enumerated. Both encapsulated and dry-plated CA and LA had higher log reductions compared to GDL (P < 0.05). However, encapsulated CA and LA at 1.0% (w/w) exhibited higher log reductions (P > 0.05) and preserved product quality compared to the dry-plated acidulants at 1.0%. We concluded that 1.0% (w/w) of encapsulated citric or lactic acids could be successfully applied as an antimicrobial intervention in raw diets for dogs.

A Familiar Outbreak of Monophasic Salmonella serovar Typhimurium (ST34) Involving Three Dogs and Their Owner's Children

Salmonella is a Gram-negative enteric bacterium responsible for the foodborne and waterborne disease salmonellosis, which is the second most reported bacterial zoonosis in humans. Many animals are potential sources of salmonellosis, including dogs, cats, and other pets. We report the case of an outbreak of salmonellosis in a family in central Italy, affecting two children and involving their three dogs as carriers. One of the children needed medical care and hospitalisation. Isolation and analysis of stool samples from the sibling and the animals present in the house were carried out. Serotyping allowed the identification of S. enterica subsp. enterica serovar Typhimurium in its monophasic variant for all the isolates. The results of whole-genome sequencing confirmed that the strains were tightly related. The minimum inhibitory concentration (MIC) test documented the resistance to ampicillin, sulfamethoxazole, and tetracycline. The origin of the zoonotic outbreak could not be assessed; however, the case study showed a clear passage of the pathogen between the human and non-human members of the family. The possibility of a transmission from a dog to a human suggests the need for further studies on the potential ways of transmission of salmonellosis through standard and alternative feed.

A review of food additives to control the proliferation and transmission of pathogenic microorganisms with emphasis on applications to raw meat-based diets for companion animals

Raw meat-based diets (RMBDs) or sometimes described as biologically appropriate raw food (BARFs) are gaining in popularity amongst dog and cat owners. These pet guardians prefer their animals to eat minimally processed and more “natural” foods instead of highly heat-processed diets manufactured with synthetic preservatives. The market for RMBDs for dogs and cats is estimated at $33 million in the United States. This figure is likely underestimated because some pet owners feed their animals raw diets prepared at home. Despite their increasing demand, RMBDs have been plagued with numerous recalls because of contamination from foodborne pathogens like Salmonella, E. coli, or Campylobacter. Existing literature regarding mitigation strategies in RMBD's for dogs/cats are very limited. Thus, a comprehensive search for published research was conducted regarding technologies used in meat and poultry processing and raw materials tangential to this trade (e.g., meats and poultry). In this review paper, we explored multiple non-thermal processes and GRAS approved food additives that can be used as potential antimicrobials alone or in combinations to assert multiple stressors that impede microbial growth, ultimately leading to pathogen inactivation through hurdle technology. This review focuses on use of high-pressure pasteurization, organic acidulants, essential oils, and bacteriophages as possible approaches to commercially pasteurize RMBDs effectively at a relatively low cost. A summary of the different ways these technologies have been used in the past to control foodborne pathogens in meat and poultry related products and how they can be applied successfully to impede growth of enteric pathogens in commercially produced raw diets for companion animals is provided.

Zoonotic Risks of Sleeping with Pets

Background: Pets are increasingly becoming part of the family and interactions between pets and their owners is changing. This results in extended and more intimate contact between owners and their pets, which give rise to zoonotic risks. Objective: To establish the presence of potential zoonotic pathogens in pets that sleep with their owner. Methods: As a pilot study, a group of 28 healthy dogs and 22 healthy cats were monitored for the presence of the zoonotic parasites Cheyletiella, Ctenocephalides spp. and Toxocara spp., the dermatophyte Microsporum canis, and the bacteria Clostridium difficile, Salmonella spp., Campylobacter jejuni and Enterobacteriaceae. This was investigated by taking samples from the fur, the footpads and the animal bed. The owners filled in a questionnaire. Results: In total, 29 of the 50 pets (58%) slept on the bed, of which 15 pets (30%) slept in the bed (under the blankets). A total of 19/22 dogs (86%) and 7/22 cats (32%) tested positive for Enterobacteriaceae on the fur or footpads. Fleas were found in 5/22 of the cats’ (23%) and 2/28 of the dogs’ (7%) favourite sleeping spots. High levels of aerobic colonies were found, up to 216 colony forming units/cm². Other pathogens were not found in this study. Conclusions: The results of this preliminary study confirm literature reports that pets may constitute a potential risk in the transmission of zoonotic pathogens to their owner, especially during direct contact when sleeping in the same bed. Owners should therefore be informed about these risks and educated to interact with their pets in a more responsible way.

Prevalence and Genomic Investigation of Multidrug-Resistant Salmonella Isolates from Companion Animals in Hangzhou, China

Salmonella is a group of bacteria that constitutes the leading cause of diarrheal diseases, posing a great disease burden worldwide. There are numerous pathways for zoonotic Salmonella transmission to humans; however, the role of companion animals in spreading these bacteria is largely underestimated in China. We aimed to investigate the prevalence of Salmonella in pet dogs and cats in Hangzhou, China, and characterize the antimicrobial resistance profile and genetic features of these pet-derived pathogens. In total, 137 fecal samples of pets were collected from an animal hospital in Hangzhou in 2018. The prevalence of Salmonella was 5.8% (8/137) in pets, with 9.3% (5/54) of cats and 3.6% (3/83) of dogs being Salmonella positive. By whole-genome sequencing (WGS), in silico serotyping, and multilocus sequence typing (MLST), 26 pet-derived Salmonella isolates were identified as Salmonella Dublin (ST10, n = 22) and Salmonella Typhimurium (ST19, n = 4). All of the isolates were identified as being multidrug-resistant (MDR), by conducting antimicrobial susceptibility testing under both aerobic and anaerobic conditions. The antibiotics of the most prevalent resistance were streptomycin (100%), cotrimoxazole (100%), tetracycline (96.20%), and ceftriaxone (92.30%). Versatile antimicrobial-resistant genes were identified, including floR (phenicol-resistant gene), blaCTX-M-15, and blaCTX-M-55 (extended-spectrum beta-lactamase genes). A total of 11 incompatible (Inc) plasmids were identified, with IncA/C2, IncFII(S), and IncX1 being the most predominant among Salmonella Dublin, and IncFIB(S), IncFII(S), IncI1, and IncQ1 being the most prevailing among Salmonella Typhimurium. Our study applied WGS to characterize pet-derived Salmonella in China, showing the presence of MDR Salmonella in pet dogs and cats with a high diversity of ARGs and plasmids. These data indicate a necessity for the regular surveillance of pet-derived pathogens to mitigate zoonotic diseases.

Temperature-Dependent Antimicrobial Activity of Menhaden Fish Oil In Vitro and on Pet Food Kibbles against Salmonella

ABSTRACT

Fish oil inclusion into a dry pet food provides a source of long-chain omega-3 fatty acids. Polyunsaturated fatty acids in fish oil have antibacterial activity against various foodborne pathogens, such as Salmonella and pathogenic Escherichia coli. The purpose of this study was to determine the effect of temperature applied to dry pet food kibbles on the antimicrobial activity of menhaden fish oil against Salmonella spp. Sterile menhaden oil was inoculated with ∼8 log of a Salmonella cocktail (∼3% moisture; Salmonella Enteritidis, Salmonella Heidelberg, and Salmonella Typhimurium) and incubated at 25, 37, and 45°C. Microbiological evaluation of the water phase was done after 2 h on tryptic soy agar. Sterile kibbles were coated with fish oil (7.0%, w/w). Canola oil coating was kept as a control. One hour after coating, the kibbles were inoculated with ∼9 log of Salmonella and incubated at the respective temperature. The microbiological evaluation was conducted at 0, 2, 6, 12, and 24 h. The oil phase of the fish oil system was negative for Salmonella after 2 h of incubation and confirmed by enrichment and PCR. From the water phase, 8.1 and 7.3 log were recovered at 25 and 37°C, respectively, and no Salmonella was detected at 45°C. On the kibble, menhaden oil had higher antimicrobial (P ≤ 0.05) activity after 12 h at 25°C and throughout the experiment at 37°C. At 45°C, the fish oil had a superior antimicrobial activity against the Salmonella cocktail after 2 h. When the fish oil alone was compared at different temperatures, a higher antimicrobial activity was observed at 37 and 45°C across all time points. The results indicate antimicrobial activity of menhaden oil increases with temperature. This is an important finding to the pet food industry: a higher fat holding temperature (∼45°C) and the application process may help mitigate Salmonella on extruded kibbles.

HIGHLIGHTS

A Cross-Sectional Study of Knowledge on Ownership, Zoonoses and Practices among Pet Owners in Northern Portugal

Simple Summary

Pet ownership is common in most countries, but few published studies have addressed pet owners’ knowledge of zoonoses, pet contact practices, or awareness of zoonotic disease risks posed by pets. The aim of this study was to assess household knowledge, attitudes, and risks related to pet ownership and zoonoses in northern Portugal. A questionnaire was developed to gather information regarding participants’ demographic characteristics; household pet types and their importance to the family; pet contact-related attitudes; knowledge of zoonoses, high-risk groups, disease transmission pathways, and disease protection measures. It was observed that most participants considered pets an important part of the family. Nevertheless, high-risk practices were recurrent and pet owners’ knowledge was limited. These results reinforce the importance of further studies to better understand the existing gaps in knowledge of pet ownership and zoonoses and strengthens the need to adopt the One Health concept.

Abstract

Pet ownership is common in modern society. In Portugal, 38% and 31% of all households own at least one dog or cat, respectively. Few studies have ascertained the knowledge of pet owners on pet ownership and zoonoses, and none have been carried out in Portugal. The aim of the present study was to assess household knowledge and practices related to pet ownership and zoonoses in northern Portugal. A face-to-face questionnaire was completed by 424 pet owners, from November 2019 to February 2020. Most respondents (97.2%) considered pets as an important part of the family, especially women (p = 0.036); 73.1% allowed their pets to live an indoor/outdoor life; 41.3% denied sharing the bed with their pets while 29% assumed they did it daily; 20.3% reported never kissing their pets/pets licking their faces. Furthermore, 73.6% considered animals as potential sources of human diseases, but only 25.9% reported knowing the definition of zoonoses; 96.9% considered the role of veterinarians important in protecting public health. The low level of knowledge of pet owners and the occurrence of high-risk behaviors indicates a need to strengthen communication between veterinarians, physicians, pet owners, and the general public towards reduce the risk of acquisition and transmission of zoonoses.

Antimicrobial Drug-Resistant Salmonella in Urban Cats: Is There an Actual Risk to Public Health?

The present study was undertaken to investigate the presence of Salmonella spp. in the faeces of client-owned cats in urban areas and to evaluate the risk that is posed to public health. Fresh faecal samples were collected directly from the rectums from 53 diarrhoeic and 32 non-diarrhoeic cats. The samples were individually screened for the presence of Salmonella spp. using standard methods and, in the case of positive findings, the resulting typical colonies were then biochemically confirmed using the VITEK^®2 automated system. Subsequently, all of the Salmonella spp. isolates were molecularly tested for the presence of the invA gene. All of the isolates were serotyped using the slide agglutination technique according to the White–Kauffmann–Le Minor scheme. The phenotypic antimicrobial susceptibility profile of the isolated strains was obtained from the VITEK^®2 system using specific cards from the Gram-negative bacteria. A total of 16 of the samples (18.82%) tested positive for Salmonella spp. according to conventional and molecular testing methods. Serotyping of the Salmonella isolates showed the presence of three serotypes, namely S. enteritidis (n = 9; 56.3%), S. typhimurium (n = 4; 25%), and S. kentucky (n = 3; 18.8%). All of the tested strains showed strong resistance towards cefazolin, cefepime, ceftazidime, and ceftriaxone. Additionally, resistance (listed in descending order of strength) was observed to trimethoprim/sulfamethoxazole (11/16; 68.8%), ampicillin (10/16; 62.5%), ampicillin/sulbactam (9/16; 56.3%), gentamicin (9/16; 56.3%), nitrofurantoin (8/16; 50.0%), and amikacin (5/16; 31.3%). No resistance was expressed against ciprofloxacin, ertapenem, imipenem, levofloxacin, piperacillin/tazobactam, and tobramycin. The results of this study highlight a substantial public health issue and medical concern, especially in vulnerable people, such as children, the elderly, and immunocompromised individuals.

The effects of raw-meat diets on the gastrointestinal microbiota of the cat and dog: a review

The aim of this review is to summarise the available literature on the effects of consuming raw, red meat diets on the gastrointestinal microbiome of the cat and dog. In recent years, feeding raw meat diets to cats and dogs has increased, in part associated with trends in human nutrition for "natural" and "species-appropriate" diets. These diets range from home-prepared unprocessed, nutritionally incomplete diets to complete and balanced diets with sterilisation steps in their manufacturing process. Feeding some formats of raw meat diets has been associated with nutritional inadequacies and zoonotic transfer of pathogens. The feeding of raw meat diets has been shown to alter the gastrointestinal microbiome of the cat and dog, increasing the relative abundances of bacteria associated with protein and fat utilisation, including members of the genera Fusobacterium and Clostridium. While in humans, these genera are more commonly known for members that are associated with disease, they are a diverse group that also contains harmless commensals that are a normal component of the gastrointestinal microbiota. Moreover, members of these genera are known to produce butyrate from protein and amino acid fermentation and contribute to intestinal homeostasis in raw meat-fed dogs and cats. Currently, only a limited number of studies have examined the impacts of raw meat diets on the cat and dog microbiota, with many of these being descriptive. Additional controlled and systems-based studies are required to functionally characterise the roles of key microbial groups in the metabolism of raw meat diets, and determine their impacts on the health and nutrition of the host.

Evaluation of nutritional value and microbiological safety in commercial dog food

In addition to properly balancing nutritional value in accordance with the needs of a dog, estimating the microbiological quality of dog food is crucial in providing healthy and safe foods. The aim of this study was to examine the quality of dry food for adult dogs, with particular reference to: (1) evaluating the nutritional value and compliance with nutritional guidelines for dogs, (2) comparing the nutritional value of dog foods, with particular emphasis on the division into cereal and cereal-free foods, and (3) evaluating their microbiological safety. All thirty-six evaluated dry dog foods met the minimum European Pet Food Industry FEDIAF requirement for total protein and fat content. The total aerobic microbial count in the analyzed dry dog foods ranged from 2.7 × 102 to above 3.0 × 107 cfu/g. In five (14%) dog foods the presence of staphylococci was detected; however, coagulase positive Staphylococcus (CPS) was not found. Mold presence was reported in one cereal-free dog food and in six cereal foods. In none of the analyzed foods Enterobacteriaceae were found, including coliforms, Escherichia coli and Salmonella spp. Bacteria of the genus Listeria and Clostridium as well as yeasts were also not detected. In conclusion, the evaluated dry dog foods had varied microbiological quality. The detected number of microorganisms may have some implications for long-term consumption of contaminated food. The lack of European Commission standards regarding the permissible amounts of microorganisms in pet food may result in insufficient quality control of these products.

High Occurrence of Shiga Toxin-Producing Escherichia coli in Raw Meat-Based Diets for Companion Animals-A Public Health Issue

Feeding pets raw meat-based diets (RMBDs) is becoming increasingly popular but comes with a risk of pathogenic bacteria, including Shiga toxin-producing Escherichia coli (STEC). In humans, STEC may cause gastrointestinal illnesses, including diarrhea, hemorrhagic colitis (HC), and the hemolytic uremic syndrome (HUS). The aim of this study was to evaluate commercially available RMBDs with regard to the occurrence of STEC. Of 59 RMBD samples, 59% tested positive by real-time PCR for the presence of Shiga toxin genes stx1 and/or stx2. STECs were recovered from 41% of the 59 samples, and strains were subjected to serotyping and virulence gene profiling, using whole genome sequencing (WGS)-based methods. Of 28 strains, 29% carried stx2a or stx2d, which are linked to STEC with high pathogenic potential. Twenty different serotypes were identified, including STEC O26:H11, O91:H10, O91:H14, O145:H28, O146:H21, and O146:H28, which are within the most common non-O157 serogroups associated with human STEC-related illnesses worldwide. Considering the low infectious dose and potential severity of disease manifestations, the high occurrence of STEC in RMBDs poses an important health risk for persons handling raw pet food and persons with close contact to pets fed on RMBDs, and is of concern in the field of public health.

Clinical health markers in dogs fed raw meat-based or commercial extruded kibble diets

The interest and demand for healthy and less processed foods for human consumption have been mirrored in the pet industry, with an explosion of alternative diets available. Several nontraditional feeding methodologies including raw meat-based diets (RMBDs) are believed by many dog owners to be superior to traditional extruded commercial dog foods. Despite the strong opinions, limited data are available comparing objective health measures among healthy dogs fed using different methods of diet preparation. Therefore, we compared health markers in client-owned dogs fed an RMBD to markers in dogs fed a high-quality extruded kibble. We hypothesized that healthy adult dogs fed RMBD would show differences in biochemical and hematological parameters and improved clinical health scores (e.g., dental, external ear canal, and integument scores) compared with dogs fed a kibble diet. A cross-sectional observational study was performed comparing hematology, serum biochemistry, urinalysis management history, and clinical health scores in healthy client-owned dogs reported as fed RMBD (n = 28) or kibble (n = 27) for >1 yr. Dental, external ear canal, and integument health scores were assigned by a single veterinary evaluator blinded to feed group, using a scale where 0 was normal and 3 was most severely affected. Spearman correlation coefficient (rs) was calculated to assess the strength and direction of the relationship of biochemical outcomes with age and body condition score (BCS), while analysis of variance was used to determine if biochemical analytes differed by breed or gender. Biochemical data were analyzed using multiple linear regression models, adjusting for the covariates gender, breed, age, and BCS. A composite clinical health score, (CCS) = 9 - (dental score + otitis score + integument score), was compared between feeding groups using Mann-Whitney test. Serum alkaline phosphatase activity (P < 0.001) and globulin concentration (P < 0.001) were lower, while lymphocyte count (P < 0.05) was higher in dogs fed RMBD. No differences were found in urinalysis between diet groups. Dogs fed RMBD showed a slight improvement in CCS compared with kibble-fed dogs (CCS: P = 0.03). Owner management significantly differed with a greater likelihood of management interventions including dietary supplements and sporting activities in the RMBD group. Further work is needed to specifically determine the impact of diet processing and nutrient content on canine health.

Modernization of Control of Pathogenic Micro-Organisms in the Food-Chain Requires a Durable Role for Immunoaffinity-Based Detection Methodology-A Review

Food microbiology is deluged by a vastly growing plethora of analytical methods. This review endeavors to color the context into which methodology has to fit and underlines the importance of sampling and sample treatment. The context is that the highest risk of food contamination is through the animal and human fecal route with a majority of foodborne infections originating from sources in mass and domestic kitchens at the end of the food-chain. Containment requires easy-to-use, failsafe, single-use tests giving an overall risk score in situ. Conversely, progressive food-safety systems are relying increasingly on early assessment of batches and groups involving risk-based sampling, monitoring environment and herd/flock health status, and (historic) food-chain information. Accordingly, responsible field laboratories prefer specificity, multi-analyte, and high-throughput procedures. Under certain etiological and epidemiological circumstances, indirect antigen immunoaffinity assays outperform the diagnostic sensitivity and diagnostic specificity of e.g., nucleic acid sequence-based assays. The current bulk of testing involves therefore ante- and post-mortem probing of humoral response to several pathogens. In this review, the inclusion of immunoglobulins against additional invasive micro-organisms indicating the level of hygiene and ergo public health risks in tests is advocated. Immunomagnetic separation, immunochromatography, immunosensor, microsphere array, lab-on-a-chip/disc platforms increasingly in combination with nanotechnologies, are discussed. The heuristic development of portable and ambulant microfluidic devices is intriguing and promising. Tant pis, many new platforms seem unattainable as the industry standard. Comparability of results with those of reference methods hinders the implementation of new technologies. Whatever the scientific and technological excellence and incentives, the decision-maker determines this implementation after weighing mainly costs and business risks.

Microbiological Hazards in Dry Dog Chews and Feeds

Nowadays, dogs are usually equally treated with other family members. Due to the growing caregivers' awareness, the pet foods industry is changing dynamically. Pet foods are manufactured with a myriad of ingredients. Few authors of scientific papers deal with the topic of foods products' safety for pet animals, assessed from the perspective of their caregivers. Despite the many methods of producing foods of the highest quality, there are still cases of contamination of pet foods and treats. In the case of dried chews for dogs, bacteria of the genus Salmonella are the most common risk. In the case of both dry and wet foods, in addition to many species of bacteria, we often deal with mold fungi and their metabolites, mycotoxins. This article presents selected microbiological risks in dog foods and treats, and analyzes the Rapid Alert System for Food and Feed (RASFF) system (2017-2020) for pathogenic microorganisms in dried dog chews, treats and foods. In this period, pet food-related notifications were registered, which were categorized into different types. Analyzing the RASFF notifications over the period, it has been shown that there are still cases of bacterial contamination of dog foods and treats, while in terms of the overall mycotoxin content, these products may appear safe.

Bacteriophage as an alternative to prevent reptile-associated Salmonella transmission

Salmonellosis is a major global public health issue; its most common infection, gastroenteritis, accounts for approximately 90 million illnesses and 150,000 mortalities per year. Eradicating salmonellosis requires surveillance, prevention and treatment, entailing large expenditures. However, it is difficult to control Salmonella transmission because it occurs via multiple routes; exotic reptiles are a reservoir of Salmonella and comprise one such route. As the popularity of exotic pets and animal exhibition has increased, human encounters with reptiles have also increased. As a result, reptile-associated salmonellosis (RAS) has been recognized as an emerging disease. The development of antimicrobial resistance in RAS-causing Salmonella sp. requires alternatives to antibiotics. In this study, bacteriophages have been established as an alternative to antibiotics because only target bacteria are lysed; thus, they are promising biocontrol agents. Here, bacteriophage pSal-SNUABM-02, which infects and lyses reptile Salmonella isolates, was isolated and characterized. The morphology, host range, growth traits and stability of the phage were investigated. The phage was assigned to Myoviridae and was stable in the following conditions: pH 5-9, 4-37°C, and ultravioletA/ultravioletB (UVA/UVB) exposure. Salmonella clearance efficacy was tested using planktonic cell lysis activity and biofilm degradation on polystyrene 96-well plates and reptile skin fragments. The phage exhibited vigorous lysis activity against planktonic cells. In in vitro biofilm degradation tests on reptile skin and polystyrene plates, both low- and high-concentration phage treatments lowered bacterial cell viability by approximately 2.5-3 log colony-forming units and also decreased biomass. Thus, bacteriophages are a promising alternative to antibiotics for the prevention and eradication of RAS.

Risk of Foodborne Illness from Pet Food: Assessing Pet Owners' Knowledge, Behavior, and Risk Perception

Pet food has been identified as a source of pathogenic bacteria, including Salmonella and Escherichia coli. A recent outbreak linked to Salmonella -contaminated pet treats infected over 150 people in the United States. The mechanism by which contaminated pet food leads to human illness has not been explicated. Pet owners' food safety knowledge and their pet food handling practices have not been reported. This study evaluated pet owners' food safety knowledge and pet-food handling practices through an online consumer survey. The survey consists of 62 questions and assesses (1) owners' food safety knowledge and pet-food handling practices; (2) owners' interaction with pets; (3) owners' risk perception related to their own health, their children's health, and their pets' health. The survey was pilot-tested among 59 pet owners before distribution to a national consumer panel, managed by Qualtrics XM. All participants (n=1,040) were dog and/or cat owners in the United States. Almost all pet owners interacted with their pets (93%) and most cuddled, allowed their pets to lick them, and slept with their pets. Less than one-third of pet owners washed their hands with soap after interacting with their pets. Over half (58%) the owners reported washing their hands after feeding their pets. Most pet owners fed their pets dry pet food and dry pet treats. Some fed their pets raw meat or raw animal product (RAP) diets because they believed these diets to be beneficial to their pet's overall health. Many owners (78%) were unaware of pet food recalls or outbreaks associated with foodborne pathogens. Less than 25% considered dry pet foods and treats as a potential source of foodborne pathogens. The findings of this study indicated the need for consumer education about pet food handling. The data collected can assist in developing more accurate risk assessment models and consumer education related to pet food handling.

When Pet Snacks Look Like Children's Toys! The Potential Role of Pet Snacks in Transmission of Bacterial Zoonotic Pathogens in the Household

Recent foodborne pathogen outbreaks associated with dry pet food and treats have focused the attention on these products as vehicles of pathogens for both pets and their owners. This study investigates the purchasing habits of dog owners and determines if and in what form pet snacks can be potentially dangerous for humans, especially for children. For these purposes, questionnaires collected from 406 dog owners were evaluated and microbiological analyses were performed on 120 dry pet snacks. The shape of the pet snack affects the purchase (median score, Mdn = 6.4) and the star bone was the preferred one (Mdn = 7.1). Most of the participants (76.0%; p < 0.001) stated that snacks are attractive to their children and that the possibility for children to get in contact with pet snacks is rare, but not implausible (Mdn = 3.1). Indeed, more than 6% of respondents admitted that there had been incidents of involuntary ingestion of pet snacks, with fever and gastrointestinal manifestations. Microbiological analyses showed that 119 dry pet snacks analyzed of a total of 120 (99.2%) were in good sanitary condition except for one sample where the presence of Listeria ivanovii was confirmed. The upward trend in the presence of pets in households and the strong and continuous growth in value and volume of the pet food market led researchers to analyze possible public health issues. Children and infants in particular are the most exposed subjects as they are more likely to come into contact with pet snacks, attracted by a shape similar to that of a toy. For this reason, although our findings did not highlight important microbiological contamination of pet snacks, it would be useful to standardize food safety criteria with those for human food from a One Health perspective.

Extended Enrichment Procedures Can Be Used To Define False-Negative Probabilities for Cultural Gold Standard Methods for Salmonella Detection, Facilitating Comparisons between Gold Standard and Alternative Methods

ABSTRACT

Evaluation of alternative detection methods for foodborne pathogens typically involves comparisons against a "gold standard" culture method, which may produce false-negative (FN) results, particularly under worst-case scenarios such as low contamination levels, difficult-to-detect strains, and challenging food matrices (e.g., matrices with a water activity of <0.6). We used extended enrichment times (up to 72 h for both primary and secondary enrichments) to evaluate a gold standard method for Salmonella detection (the U.S. Food and Drug Administration Bacteriological Analytical Manual [BAM] method) in two low-water-activity foods (dry pet food and chocolate) inoculated at low contamination levels (most probable number ca. 1/25 g) with five Salmonella strains. Strains were selected to include those with a poor ability to grow in enrichment media. Among the 100 pet food and 100 chocolate samples tested, 53 and 50, respectively, were positive with the standard BAM method, and 57 and 59, respectively, were positive with the extended BAM method. Thus, the FN probabilities for the standard BAM method were 7% for pet food and 15% for chocolate. An alternative enzyme immunoassay method for detection of Salmonella in chocolate produced FN probabilities of 6 and 20% when compared against the standard and extended BAM methods, respectively. Detection of Salmonella Mississippi was significantly reduced with the alternative method (P = 0.023) compared with the extended BAM method. We calculated a composite reference standard to further define FN probabilities based on variable results from multiple assays (the standard BAM, extended BAM, and alternative methods). Based on this standard, the enzyme immunoassay for Salmonella detection in chocolate had a 28% FN probability and the standard and extended BAM methods had 23 and 9% FN probabilities, respectively. These results provide a framework for how inclusion of extended enrichment times can facilitate evaluation of alternative detection methods.

HIGHLIGHTS

Evaluating the presence of human pathogens in commercially frozen, biologically appropriate raw pet food sold in Italy

BACKGROUND

Biologically appropriate raw food (BARF) diet is becoming more and more popular among pet owners in Europe. However, there are documented microbiological risks associated with raw feeding, and this study aimed to determine the presence of human pathogens in commercially frozen BARF products sold in Italy.

METHODS

Salmonella species, Escherichia coli O157:H7, Listeria monocytogenes and Campylobacter species were identified. The general microbiological quality of BARF products and hygiene were also evaluated. Sample size was limited and therefore the study may not be representative of a larger sample.

RESULTS

None of the tested samples showed total bacterial count (TBC) higher than the limit set to consider a sample unacceptable. However, 14 out of 21 samples showed TBC higher than the limit set to consider a sample marginally acceptable. A high percentage of samples were contaminated by the aforementioned pathogens, highlighting the need for pet owners to be aware of the risks of this feeding strategy both to themselves and to their pets.

CONCLUSIONS

Considering that BARF diet meals can be prepared at home using the hands, as well as tools and spaces that could be shared, guidelines on safer handling of these pet food products should be recommended by veterinarians and nutritionists.

Exposures Associated with Non-Typhoidal Salmonella Infections Caused by Newport, Javiana, and Mississippi Serotypes in Tennessee, 2013-2015: A Case-Case Analysis

Non-typhoidal Salmonella (NTS) infection (salmonellosis) is one of the most prevalent gastrointestinal diseases throughout the world. Human infections caused by Salmonella Newport, Javiana, and Mississippi serotypes have been observed to occur at higher rates on an annual basis in western Tennessee. The reason for the increased rate of NTS infection by these three serotypes in this region is not known. We conducted a case-case analysis to identify potential risk factors associated with the three Salmonella serotypes using FoodNet data, obtained from the Tennessee Department of Health, consisting of 1578 culture-confirmed salmonellosis cases in Tennessee from 2013 through 2015. Among all the exposure variables tested (254 in total), we found contact with pet treats or chews in the seven days prior to illness was the factor that was significantly associated with these serotypes compared to other serotypes (odds ratio _adjusted = 3.0 (95% confidence intervals 1.6, 5.5), P < 0.0005). This study highlights the need for further investigation of potential exposures (other than pet treats or chews), including several possible environmental sources of NTS infection in humans.

Assessing the Efficacy of Sodium Bisulfate and Organic Acid Treatments for Control of Salmonella Typhimurium in Rendered Chicken Fat Applied to Pet Foods

This study was conducted to evaluate the effects of sodium bisulfate (SBS), lactic acid (LA), phosphoric acid (PA), and combinations of organic acids with SBS on Salmonella in rendered chicken fat and in water. The MICs of the antimicrobials individually and in combination were determined. Efficacies of the antimicrobials against Salmonella were tested in both media. The MICs of SBS, LA, and PA were 0.5, 0.5, and 0.25%, respectively. At the given concentrations in the water phase, 0.5% SBS was more effective (P < 0.05; 2.7-log reduction) than LA and PA at 0 h. SBS and LA were more effective (P < 0.05) than PA with >4-log reductions at 2 h and complete kill at 6 h. After 24 h, each of the chemicals completely eliminated the Salmonella. However, because of low recovery in the fat phase, Salmonella was not detected after 12 h and all three chemicals effectively reduced (P < 0.05) Salmonella at 6 h compared with the control. When combinations were used in the water phase, SBS plus butyric acid decreased (P < 0.05) Salmonella by >5.5 log CFU/mL after 12 h. The SBS+LA combinations were effective (P < 0.05) after 2 h. The combinations of SBS+PA resulted in ∼3.5-log reductions in Salmonella (P < 0.05) after 6 h. In the fat phase, except for the SBS+PA combination, Salmonella reduction was not different from that for the positive control. When SBS was combined with organic acids, Salmonella inhibition was achieved at a lower SBS concentration, indicating a possibly synergistic effect of these chemicals. These results suggest that inclusion of SBS or LA at 0.5% individually or a combination of SBS with organic acids could reduce Salmonella in rendered chicken fat contaminated by residual water encountered during storage and transport.

Raw meat-based diets for companion animals: a potential source of transmission of pathogenic and antimicrobial-resistant Enterobacteriaceae

Feeding pets raw meat-based diets (RMBDs) has become increasingly popular but may constitute a risk due to the contamination with pathogenic and antimicrobial-resistant (AMR) bacteria. The aim of this study was to evaluate commercially available RMBDs with regard to microbiological quality and occurrence of AMR Enterobacteriaceae. Of 51 RMBD samples, 72.5% did not meet the microbiological standards for Enterobacteriaceae set out by EU regulations for animal by-products intended for pet food. Furthermore, Salmonella was detected in 3.9% of the samples. AMR bacteria were found in 62.7% of the samples, the majority thereof were resistant to third-generation cephalosporins due to the production of extended-spectrum β-lactamases (ESBLs) including CTX-M-1, which is widespread in livestock, and CTX-M-15, which is the most common ESBL variant worldwide. Colistin- and aminoglycoside-resistant isolates, producing MCR-1 and RMTB, were identified in 3.9 and 2% of the samples, respectively. The majority of the AMR Escherichia coli belonged to commensal groups A or B1 and were associated with clonal complexes CC155 and CC10. Two belonged to the emerging extraintestinal pathogenic CC648, and one to the globally disseminated uropathogenic E. coli sequence type ST69, suggesting zoonotic potential. The microbiological quality and the high prevalence of AMR producing Enterobacteriaceae in RMBDs raise concerns for animal and public health.

Tuberculosis due to Mycobacterium bovis in pet cats associated with feeding a commercial raw food diet

OBJECTIVES

Mycobacterium bovis, a member of the Mycobacterium tuberculosis complex, can infect cats and has proven zoonotic risks for owners. Infected cats typically present with a history of outdoor lifestyle and hunting behaviour, and cutaneous granulomas are most commonly observed. The aim of this study is to describe an outbreak of tuberculous disease commencing with six young cats, living exclusively indoors in five different households across England, being presented to separate veterinarians across the UK with a variety of clinical signs.

METHODS

Investigations into the pyogranulomatous lesions, lymphadenopathy and/or pulmonary disease of these cases consistently identified infection with M bovis. Infection was confirmed by PCR, where possible, or was indicated with a positive interferon-gamma release assay (IGRA), where material for PCR was unavailable. In-contact, cohabiting cats were screened by IGRA and follow-up testing was undertaken/advised where results were positive. A lifestyle investigation was undertaken to identify the source of infection.

RESULTS

Six clinically sick cats and seven in-contact cats were identified with evidence of M bovis infection. Five clinical cases were either too sick to treat or deteriorated despite therapy, giving a mortality rate of 83%. Lifestyle investigations revealed the common factors between clusters to be that affected cats had mycobacterial infections speciated to M bovis, were exclusively indoor cats and were fed a commercially available raw food product produced by a single manufacturer. The Food Standards Agency, Animal & Plant Health Agency, Public Health England and the food manufacturer concerned have been notified/informed. Other possible sources of exposure for these cats to M bovis were explored and were excluded, including wildlife contact, access to raw milk, the presence of rodent populations inside the buildings in which the cats lived and exposure to known infectious humans.

CONCLUSIONS AND RELEVANCE

Upon investigations, our results provide compelling, if circumstantial, evidence of an association between the commercial raw diet of these cats and their M bovis infections.

Raw diets for dogs and cats: a review, with particular reference to microbiological hazards

There is a recent trend to feed pet dogs and cats in Britain and other developed countries on raw meat and animal by-products using either commercial preparations or home recipes. This shift from heat-treated processed food has been driven by perceived health benefits to pets and a suspicion of industrially produced pet food. The diets of wild-living related species have been used as a rationale for raw feeding, but differences in biology and lifestyle impose limitations on such comparisons. Formal evidence does exist for claims by raw-feeding proponents of an altered intestinal microbiome and (subjectively) improved stool quality. However, there is currently neither robust evidence nor identified plausible mechanisms for many of the wide range of other claimed benefits. There are documented risks associated with raw feeding, principally malnutrition (inexpert formulation and testing of diets) and infection affecting pets and/or household members. Surveys in Europe and North America have consistently found Salmonella species in a proportion of samples, typically of fresh-frozen commercial diets. Another emerging issue concerns the risk of introducing antimicrobial-resistant bacteria. Raw pet food commonly exceeds hygiene thresholds for counts of Enterobacteriaceae. These bacteria often encode resistance to critically important antibiotics such as extended-spectrum cephalosporins, and raw-fed pets create an elevated risk of shedding such resistant bacteria. Other infectious organisms that may be of concern include Listeria, shiga toxigenic E scherichia coli , parasites such as Toxoplasma gondii and exotic agents such as the zoonotic livestock pathogen Brucella suis, recently identified in European Union and UK raw pet meat imported from Argentina.

Occurrence of Salmonella, Campylobacter, Clostridium and Enterobacteriaceae in raw meat-based diets for dogs

The practice of feeding raw meat-based diets (RMBD) to dogs has increased in popularity in recent years. However, RMBD are based on offal that has not undergone any type of treatment to reduce the microbial content, so there is a risk of potential pathogenic microorganisms being present. Frozen samples from 60 RMBD packs produced by 10 different manufacturers were analysed for their content of bacteria belonging to the family Enterobacteriaceae, for Clostridium perfringens and for the presence of Salmonella and Campylobacter. Enterobacteriaceae were detected in all 60 samples and in 31 samples exceeded a level of 5000 bacteria/g, which is the threshold for satisfactory microbial hygiene according to EU regulations. In two samples, the amount of C. perfringens exceeded 5000 bacteria/g, which is the maximum level of anaerobic bacteria permitted by Swedish national guidelines. Salmonella species were found in four (7 per cent) and Campylobacter species in three (5 per cent) samples. These results show that it is critical to maintain good hygiene when storing, handling and feeding RMBD, in order to limit the potential health risks to animals and humans, especially young and immunocompromised individuals.

Prevalence of Salmonella in juvenile dogs affected with parvoviral enteritis

Salmonellosis is a disease of major zoonotic importance and canine parvovirus is a potentially fatal cause of canine enteritis with a world-wide distribution. Persistent isolation of Salmonella during routine environmental sampling surveys of a hospital ward, reserved for the treatment of dogs with canine parvovirus infection, prompted investigation into a possible source. We hypothesised that dogs affected by canine parvovirus would have a higher prevalence of faecal salmonellae compared to an apparently healthy cohort. Seventy-four client-owned dogs naturally infected with canine parvovirus and 42 apparently healthy client-owned dogs were included in the study. This prospective, longitudinal, observational study was conducted over an 18-month period. Fresh faecal samples were collected from dogs aged 6 weeks to 9 months diagnosed with canine parvovirus infection and admitted for treatment, and from apparently healthy dogs presented for vaccination or routine hospital procedures. Faeces were submitted for the isolation, antimicrobial susceptibility testing and serotyping of salmonellae. The prevalence of faecal Salmonella shedding was 22% and 31% for the affected and apparently healthy dogs, respectively, which was not statistically different. No significant associations between Salmonella status and possible risk factors or continuous variables such as age, body weight and duration of hospitalisation were identified. All the Salmonella isolates (n = 32) were resistant to penicillin G, lincomycin and tylosin. Salmonellae from nine different serotypes were identified. The prevalence of Salmonella shedding in both groups was higher than that commonly reported, yet similar to those in previous reports on young dogs, shelter dogs or dogs fed a raw meat diet.

The problem of diagnosis of generalized and focal forms of salmonellosis

The article describes the clinical observation with an unfavorable outcome of the generalized form of salmonella infection caused by Salmonella typhimurium group B in a woman of 60 years without immunodeficiency, complicated by the development of multiple abscesses of the lower parts of abdominal cavity, probably of appendicular origin. In a short literary review, the pathogenetic mechanisms that contribute to the formation of generalized and extraintestinal forms of salmonella infection are discussed.

Measuring animal exposure in Canada: Foodbook study, 2014-2015

Animal companionship can have many physical and psychological benefits; however, animals can also be a source of zoonotic infection, including enteric illnesses; it has been estimated that in Canada, nearly 85,000 enteric illnesses due to eight pathogens occur each year related to animal contact. There is a lack of baseline data on animal-related exposures in Canada and around the world. This information is critical to inform quantitative and qualitative risk assessments to prioritize intervention efforts in public health and reduce the associated burden of enteric illness. To help address this issue and assist evaluation of the risks associated with animal contact, the Foodbook study, conducted in 2014-2015, assessed exposure to animals, animal food and animal-related venues within the last 7 days among Canadians. Data were analysed by province and territory, age group and urban/rural residency. Overall, dogs and cats were the most commonly reported animal exposures (43.3% and 31.9%, respectively). The data suggest farm animal exposure occurs primarily at a farm/barn, and to a lesser extent at other animal-related venues (e.g., petting zoos or agricultural fairs). Approximately one in 25 respondents handled raw pet food within the last 7 days; the majority of which had also been exposed to a dog (86.4%). Children aged 0-9 years reported relatively high exposure to four types of high-risk animals: rodents (5.6%), poultry (4.0%), reptiles (2.1%) and amphibians (1.8%); with the most vulnerable children aged <5 years also reporting exposure to many of these high-risk animals. These results highlight potential areas for targeted intervention that can focus on high-risk populations (e.g., young children) exhibiting potentially risky behaviour such as being exposed to certain high-risk animals, or handling pet food, treats and raw pet food diets. Additionally, these results support the need to better understand the burden of enteric illness associated with animals and their environments.

Cats and Carbohydrates: The Carnivore Fantasy?

The domestic cat’s wild ancestors are obligate carnivores that consume prey containing only minimal amounts of carbohydrates. Evolutionary events adapted the cat’s metabolism and physiology to this diet strictly composed of animal tissues and led to unique digestive and metabolic peculiarities of carbohydrate metabolism. The domestic cat still closely resembles its wild ancestor. Although the carnivore connection of domestic cats is well recognised, little is known about the precise nutrient profile to which the digestive physiology and metabolism of the cat have adapted throughout evolution. Moreover, studies show that domestic cats balance macronutrient intake by selecting low-carbohydrate foods. The fact that cats evolved consuming low-carbohydrate prey has led to speculations that high-carbohydrate diets could be detrimental for a cat’s health. More specifically, it has been suggested that excess carbohydrates could lead to feline obesity and diabetes mellitus. Additionally, the chances for remission of diabetes mellitus are higher in cats that consume a low-carbohydrate diet. This literature review will summarise current carbohydrate knowledge pertaining to digestion, absorption and metabolism of carbohydrates, food selection and macronutrient balancing in healthy, obese and diabetic cats, as well as the role of carbohydrates in prevention and treatment of obesity and diabetes mellitus.

Evaluation of raw pork as a commercially manufactured diet option for zoo-managed African wildcats (Felis silvestris lybica)

Second to beef, pork is a major protein source produced in the US. Properly sourced and handled pork could be utilized as a protein option for zoo-managed carnivores. Concerns of high levels of microbial populations in raw meat diets are common. The objectives of this study were to determine apparent total tract macronutrient and energy digestibility and fecal scores from cats fed a commercially manufactured raw pork-based diet compared with commercially available raw carnivore diets formulated with either horse or beef and evaluate typical microbial population variation among the diets. Dietary treatments consisted of 4 raw meat-based diets: Horse, Beef, Pork, and beef/horse Blend. All diets were highly digestible, especially fat digestibility (98.6 to 99.7%) in which there were no statistical differences among diets. Digestibility of organic matter (OM) was greater (P = 0.05) when cats consumed the Blend diet (97.2%) compared to the Pork diet (93.1%). Fecal scores ranged from 1.6 to 2.6 (on a 5-point scale), with Beef (2.6) being greater than (P = 0.01) Horse (1.6) and (P = 0.02) Pork (1.9). E. coli counts ranged from 110 to 10,000 cfu/g; total coliforms: 150 to 28,000 cfu/g; yeast: 20 to 4,000 cfu/g; mold count: not detectable to 10 cfu/g; and aerobic plate count: 23,000 to 26,000,000 cfu/g. Staphylococcus aureus was not detected in any of the diets. Salmonella was presumptive positive in the Pork and Blend diet, and was negative in the other 2 diets. In conclusion, commercially manufactured diets have varying microbial counts. All diets, including the raw pork-based diet were well utilized by exotic small cats and can be included among dietary options for managed felids.

Highly suspected cases of salmonellosis in two cats fed with a commercial raw meat-based diet: health risks to animals and zoonotic implications

BACKGROUND

Feeding raw meat-based diets (RMBD) to companion animals raises public health concerns for both animals and humans. While considerable attention has been paid to bacterial contamination of commercial pet food, few literature studies have investigated foodborne disease in companion animals. Salmonellosis is reported to be infrequent in cats but no known data or studies estimating feline salmonellosis are available or large-scale epidemiological studies assessing Salmonella risk factors.

CASE PRESENTATION

Two highly suspected cases of salmonellosis in two cats fed with a commercial frozen poultry RMBD are presented, for the first time from the same household. The clinical presentation, diagnostics, treatment and follow-up are reported and the zoonotic implications are discussed.

CONCLUSIONS

This case highlights the health risks posed to both animals and owners by feeding RMBD to pets, and suggests that these risks should be considered by veterinary practitioners.

Raw Meat-Based Diets in Dogs and Cats

Feeding pets raw meat-based diets (RMBDs) is commonly practiced by many companion animal owners and has received increasing attention in recent years. It may be beneficial for the animals, but may also pose a health risk for both pets and their owners, as RMBDs may be contaminated by enteric pathogens-such as Campylobacter, Salmonella, and Yersinia-which are the most common zoonotic bacteria causing enteritis in humans. Little information exists on the prevalence of these pathogens in pet food, and thus one aim was to investigate the prevalence of Campylobacter, Salmonella, and Yersinia in commercial RMBDs from retail stores. Little evidence also exists on the significance of raw meat feeding on the shedding of Campylobacter, Salmonella, and enteropathogenic Yersinia in the feces of pets, and therefore, the second goal was to study the presence of these pathogens in dogs and cats fed RMBDs. Polymerase chain reaction (PCR) only sporadically detected Campylobacter, Salmonella, and enteropathogenic Yersinia in RMBDs. These pathogens were not found by culturing, indicating a low contamination level in frozen RMBDs. They were also detected in the feces of dogs and cats, but the association with feeding RMBDs to them remained unclear.

Kidney allograft pyelonephritis caused by Salmonella enterica serovar Schwarzengrund

Kidney transplant recipients (KTRs) taking immunosuppressive drugs have a 20-fold greater risk of nontyphoidal Salmonella (NTS) infection than the healthy adult population. Among KTRs, the urinary tract is the most common site of infection. However, few cases of urinary tract infection caused by NTS have been documented in KTRs, and only one in Japan. Furthermore, it frequently induces acute allograft rejection with high mortality. Salmonella enterica subsp. enterica serovar Schwarzengrund (S. Schwarzengrund) is now among the more common Salmonella serovars isolated in Japan and is likely to be invasive. We present a case of a 45-year old female with vesicoureteral reflux to her transplanted kidney who developed kidney allograft pyelonephritis caused by S. Schwarzengrund. She was admitted to our hospital with fever, urodynia, lower abdominal pain, gross hematuria, and cloudy urine. Urine cultures were positive for S. Schwarzengrund. Exposure to cats, especially stray cats, were identified as the most likely source. We administered antibiotics for 4 weeks (ceftriaxone then amoxicillin, each for 2 weeks) and educated her about pet safety. She experienced no recurrence of infection or clinical kidney allograft rejection for 3 months post-treatment. NTS should be considered as a possible pathogen of urinary tract infection among KTRs, especially in cases with animal exposure or structural urologic abnormalities. When the pathogen is NTS, appropriate antibiotics and treatment periods are essential for preventing recurrence and allograft rejection after the completion of treatment.

Descriptive study of enteric zoonoses in Ontario, Canada, from 2010 - 2012

BACKGROUND

Contact with animals and their environment has long been recognized as an important source of enteric zoonoses. However, there are limited data available on the burden of illness associated with specific types of animals in Canada. This study describes the overall burden of enteric zoonoses in Ontario, Canada from 2010 to 2012.

METHODS

Confirmed cases of seven enteric zoonotic diseases (campylobacteriosis, cryptosporidiosis, giardiasis, listeriosis, salmonellosis, verotoxin-producing E. coli (VTEC) infection, and yersiniosis) with episode dates from 2010 to 2012 were extracted from the integrated Public Health Information System (iPHIS). Reported exposures were categorized as animal contact, foodborne, waterborne and 'other', with animal contact grouped into nine sub-categories based on the type of animal or transmission setting. Overall incidence rates and proportions by animal exposure categories, age and sex-specific incidence rates and hospitalization and death proportions were calculated and sex proportions compared.

RESULTS

Our study found that approximately 26% of the enteric pathogens assessed during the 2010 to 2012 period reported contact with animals and their environments as the mode of transmission. Of enteric disease cases reporting animal contact, farm exposures were reported for 51.3%, dog or cat exposures for 26.3%, and reptile or amphibian exposures for 8.9%.

CONCLUSIONS

Contact with animals was reported more frequently during the period 2010 to 2012 in comparison to the period 1997 to 2003 when 6% or less of enteric cases were associated with animal contact. Public health professionals, stakeholders associated with animals and their related industries (e.g., pet treats, mobile zoos, abattoirs), and the public should recognize that animal contact is an important source of enteric illnesses in order to take measures to reduce the burden of illness from animal sources.

Bacteriophages safely reduce Salmonella contamination in pet food and raw pet food ingredients

Contamination of pet food with Salmonella is a serious public health concern, and several disease outbreaks have recently occurred due to human exposure to Salmonella tainted pet food. The problem is especially challenging for raw pet foods (which include raw meats, seafood, fruits, and vegetables). These foods are becoming increasingly popular because of their nutritional qualities, but they are also more difficult to maintain Salmonella-free because they lack heat-treatment. Among various methods examined to improve the safety of pet foods (including raw pet food), one intriguing approach is to use bacteriophages to specifically kill Salmonella serotypes. At least 2 phage preparations (SalmoFresh® and Salmonelex™) targeting Salmonella are already FDA cleared for commercial applications to improve the safety of human foods. However, similar preparations are not yet available for pet food applications. Here, we report the results of evaluating one such preparation (SalmoLyse®) in reducing Salmonella levels in various raw pet food ingredients (chicken, tuna, turkey, cantaloupe, and lettuce). Application of SalmoLyse® in low (ca. 2-4×10⁶ PFU/g) and standard (ca. 9×10⁶ PFU/g) concentrations significantly (P < 0.01) reduced (by 60-92%) Salmonella contamination in all raw foods examined compared to control treatments. When SalmoLyse®-treated (ca. 2×10⁷ PFU/g) dry pet food was fed to cats and dogs, it did not trigger any deleterious side effects in the pets. Our data suggest that the bacteriophage cocktail lytic for Salmonella can significantly and safely reduce Salmonella contamination in various raw pet food ingredients.

Modeling the long-term kinetics of Salmonella survival on dry pet food

Due to multiple outbreaks and large-scale product recalls, Salmonella has emerged as a priority pathogen in dry pet food and treats. However, little data are available to quantify risks posed by these classes of products to both pets and their owners. Specifically, the kinetics of Salmonella survival on complex pet food matrices are not available. This study measured the long-term kinetics of Salmonella survival on a dry pet food under storage conditions commonly encountered during production, retail, and in households (aw < 0.60, 23 °C). A Salmonella enterica cocktail of 12 strains isolated from dry pet foods and treats was used to inoculate commercial dry dog food. Salmonella was enumerated on non-selective (BHI) and selective (XLD and BS) media. Results at 570 days indicated an initial relatively rapid decline (up to 54 days), followed by a much slower extended decline phase. The Weibull model provided a satisfactory fit for time series of Log-transformed Salmonella counts from all three media (δ: mean 4.65 day/Log (CFU/g); p: mean 0.364 on BHI). This study provides a survival model that can be applied in quantitative risk assessment models.

[Raw-meat-based diets (RMBD) as a feeding principle for dogs]

BARF (Bone And Raw Food) is an increasing trend for feeding dogs in Germany. This article provides an overview of the history and principles of this type of feeding. Risks of feeding raw-meat diets include infections of dogs with parasites, bacteria and viruses. Some of these pathogenic organisms also have zoonotic potential. Additionally, raw-meat diets often show nutritional imbalances. Over-supplementation and deficiencies of nutrients are frequently found, especially regarding calcium, the trace elements copper, zinc and iodine, vitamins A and D and the calcium   :   phosphorus ratio. This malnutrition can cause clinical symptoms. Therefore, checking and optimising the diet by a specialized veterinarian is strongly recommended.

Acceptance, Benefits, and Challenges of Public Health-Oriented Pet Business Regulations in King County, Washington

CONTEXT

New regulations were implemented in King County, Washington, in 2010 requiring pet businesses to obtain a permit from Public Health-Seattle & King County (Public Health) and undergo annual inspections to provide education and ensure compliance with regulatory standards. The regulations were developed as a tool for zoonotic disease control and prevention education for businesses and their customers, as well as for environmental protection.

OBJECTIVE

To assess the acceptance, benefits, and challenges of the new regulations and identify ways for Public Health to improve educational efforts and assist businesses with compliance.

DESIGN

Cross-sectional survey.

SETTING

King County, Washington.

PARTICIPANTS

Pet businesses with Public Health permits in 2013.

MAIN OUTCOME MEASURE

Self-administered survey responses.

RESULTS

The response rate was 40.5%. The majority of respondents provided grooming, pet day care, and kennel/boarding services from small, independent businesses. Sixty-one percent reported Public Health inspections as beneficial, especially concerning disinfection procedures and using an infection control plan. Almost three-fourths of respondents used the Public Health template to develop the infection control plan. Forty-four percent reported using the educational materials provided by Public Health, and 62% used educational materials from other sources. Most respondents reported that they gained benefits from the pet business permit, although fewer agreed that they obtained a good value from the permit and fee. The most common benefits reported were protection of animal and human health and establishing the credibility of the pet business.

CONCLUSIONS

Major challenges with the implementation of the pet business regulations were not generally reported by respondents. Most respondents reported a collaborative relationship between Public Health and the pet businesses. Improvements in infection control practices and positive responses to the inspections were reported by pet businesses. Survey results were used to improve infection control plan templates, increase the use of educational materials, and improve the Web site and business portal performance.

Evaluating Pediococcus acidilactici and Enterococcus faecium NRRL B-2354 as Thermal Surrogate Microorganisms for Salmonella for In-Plant Validation Studies of Low-Moisture Pet Food Products

Pediococcus acidilactici ATCC 8042 and Enterococcus faecium NRRL B-2354 were investigated as potential surrogates for Salmonella serovars using thermal death time kinetics in products such as dry pet foods. The D-values of P. acidilactici ATCC 8042, E. faecium NRRL B-2354, and a cocktail of seven Salmonella serovars associated with low-moisture products were determined in a preservative-free dry pet food product at moisture levels of 9.1, 17.9, and 27.0% and heated between 76.7 and 87.8°C. The D-values were calculated by least squares linear regression. The D-values of P. acidilactici ATCC 8042 were higher than those for the Salmonella serovar cocktail but lower than those for E. faecium NRRL 2354. At 9.1% moisture, D-values of 6.54, 11.51, and 11.66 min at 76.7°C, 2.66, 3.22, and 4.08 min at 82.2°C, and 1.07, 1.29, and 1.69 min at 87.8°C were calculated for Salmonella serovars, P. acidilactici ATCC 8042, and E. faecium NRRL B-2354, respectively. The data suggest that the thermal inactivation characteristics of P. acidilactici ATCC 8042 can be utilized as a surrogate to predict the response of Salmonella in dry pet food products that are thermally processed at <90°C.