Canine Food Research Articles

Individual and combined occurrences of the prevalent mycotoxins in commercial feline and canine food.

Mycotoxins, such as aflatoxin B1 (AFB1), deoxynivalenol (DON), fumonisins (FBs), ochratoxin A (OTA), T-2 toxin (T-2), and zearalenone (ZEN), can contaminate animal feeds and pose risks to animal health and production performance. These mycotoxins are commonly found in cereals and grains, with the increased use of cereals in pet food, there is a rising concern about mycotoxin contamination among pet owners. To address this, we analyzed imported brands of feline and canine food from the Chinese market produced in 2021-2022. Ninety-three samples were analyzed, comprising 45 feline food and 48 canine food samples. Among them, 14 were canned food and 79 were dry food. The results indicate that AFB1, DON, FBs, OTA, T-2, and ZEN occurred in 32.26%, 98.92%, 22.58%, 73.12%, 55.91%, and 7.53% of the samples, respectively. The most prevalent mycotoxin was DON, followed by OTA, T-2, AFB1, and FBs, whereas ZEN was less frequently detected. The mean concentrations of the six mycotoxins in pet feed samples were 3.17μg/kg for AFB1, 0.65mg/kg for DON, 2.15mg/kg for FBs, 6.27μg/kg for OTA, 20.00μg/kg for T-2, and 30.00μg/kg for ZEN. The levels of mycotoxins were generally below the limits of the Pet Feed Hygiene Regulations of China and the EU. Notably, a substantial majority of the pet food samples (88 out of 93) were contaminated by two or more mycotoxins. AFB1, FBs, OTA, and ZEN occurred slightly more often in feline food than in canine food. Except for OTA, the contamination rates for the other five mycotoxins in canned food were lower than those in dry food. Moreover, except for AFB1, the levels of the other five mycotoxins in canned foods were lower than those in dry foods. This study highlights the widespread contamination of pet foods with mycotoxins, which poses a significant risk to pets from continuous exposure to multiple mycotoxins.

Edible insects as a source of dietary protein for companion animals with food responsive enteropathies – perspectives and possibilities

The incidence of chronic enteropathies (CE), in particular food-responsive enteropathies (FRE) in dogs, is on the rise in veterinary practice. The symptoms of these digestive disorders cannot be alleviated with the use of commercial hypoallergenic feeds. The applicability of novel materials in hypoallergenic dog feeds is limited, and edible insects could pose a viable alternative. Insects have a high nutritional value, and their potential can be harnessed to design personalized nutrition strategies. However, the use of insects in animal feeds should be rigorously tested. The aim of this study was to analyze the applicability of edible insects as a source of dietary protein for companion animals, including the current and future prospects. Canine food formulas should be evaluated in a clinical setting. The role edible insects in pet diets and the efficacy of this material in animal nutrition should be examined in advanced clinical trials in gastroenterology, histology, immunology, and microbiology. These efforts are required to guarantee the safety and efficacy of innovative insect-based feeds and to increase their popularity among veterinary practitioners, pet food producers, and animal owners.

Amanitin determination in bile samples by UHPLC-MS: LR-MS and HR-MS analytical performance

Consumption of misidentified foraged mushrooms containing bicyclic amanitin octapeptides is a worldwide public health and veterinary problem, being considered one of the deadliest accidental human and canine food ingestion due to acute liver failure (ALF). Reversal of advanced ALF and complete clinical recovery can be achieved following definitive removal of accumulated amatoxin laden bile from the gallbladder. An accurate means of quantifying amanitin content in aspirated bile is, therefore, urgently needed. Building on our prior work validating a method to detect and quantify amanitin in hepatic autopsy tissue, the development of an accurate method of measuring α- and β-amanitin in aspirated gallbladder bile was performed to evaluate the efficiency of this emergency procedure applied as a clinical treatment for intoxicated patients. A solid-phase extraction (SPE) procedure was optimized followed by detection based on ultra-high performance liquid chromatography coupled with mass spectrometry (UHPLC-MS). Low resolution mass spectrometry (LRMS) was compared with high resolution (HRMS) by the validation of UHPLC-MS/MS (triple quadrupole MS) and UHPLC-ToF-MS (time-of-flight MS). Both methods were able to detect amatoxins in bile with limits of detection and quantification ranging from 2.71 to 3.46 µg.kg-1, and 8.36–9.03 µg.kg-1 for α-amanitin and, 0.32–1.69 µg.kg-1 and 0.55–5.62 µg.kg-1 for β-amanitin, respectively. Validation was completed with the evaluation of linearity, specificity, robustness, recovery, and precision following the ICH guidelines and CIR 808/2021. The validated methods were finally applied to bile samples obtained 48–96 hours + post-ingestion from 4 amatoxin poisoning patients who underwent gallbladder drainage procedures in Vietnam, Canada, and California. Gallbladder bile from patients with amatoxin mushroom poisoning contained significant amanitin content, even when aspirated several days post-ingestion, thus confirming the important role of enterohepatic circulation in amatoxin hepatotoxicity. This work represents a high and unique analytical throughput in amanitin poisoning allowing to efficiently respond to this fatal health problem.

Modulation of digestibility of canine food using enzyme supplement: an in vitro simulated semi-dynamic digestion study.

Digestibility and nutrient availability are important parameters when estimating the nutritional quality of pet food. We have developed a simulated semi-dynamic in vitro canine digestion model to evaluate the digestibility of dry extruded canine food. Canine food was assessed for digestible energy, dry matter digestibility, protein digestibility, non-fibrous carbohydrate (NFC) digestibility, and total antioxidant capacity (TAC) in the absence and presence of an enzyme blend (DigeSEB Super Pet). Enzyme blend supplementation in canine food was found to increase the dry matter digestibility (18.7%, p < 0.05), digestible energy (18.1%, p < 0.05), and protein digestibility (11%, p < 0.1) and reducing sugar release (106.3%, p < 0.005). The release of low molecular weight peptides (48.7%) and essential amino acids (15.6%) increased within 0.5 h of gastrointestinal digestion due to enzyme blend supplementation. Furthermore, the TAC of the digesta was also increased (8.1%, p < 0.005) in the canine food supplemented with enzyme blend. Overall, supplementation of enzyme blend in canine food is an effective strategy to enhance the food digestibility and nutrient availability for absorption.

Determining the protocol requirements of in-home dog food digestibility testing.

In-home pet food testing has the benefit of yielding data which is directly applicable to the pet population. Validated and standardised in-home test protocols need to be available, and here we investigated key protocol requirements for an in-home canine food digestibility protocol. Participants were recruited via an online survey. After meeting specific inclusion criteria, sixty dogs of various breeds and ages received, during 14 consecutive days, a relatively low and high digestible complete dry extruded food containing titanium (Ti) dioxide. Both foods were given for 7 d in a cross-over design. Owners collected faeces daily allowing daily faecal Ti concentrations and digestibility of nitrogen (N), dry matter (DM), crude ash, organic matter (OM), crude fat (Cfat), starch and gross energy (GE) to be determined. Faecal Ti and digestibility values for all nutrients were not different (P > 0·05) from the second day onwards after first consumption for both foods. One day of faecal collection yielded reliable digestibility values with additional collection days not reducing the confidence interval around the mean. Depending on the accepted margin of error, the food and the nutrient of interest, the minimal required sample size was between 9 and 43 dogs. Variation in digestibility values could in part be explained by a dog's neuter status (N, crude ash) and age (crude ash, Cfat) but not sex and body size. Future studies should focus on further identifying and controlling sources of variation to improve the in-home digestibility protocol and reduce the number of dogs required.

Effect of Polysaccharides on the Physical, Rheological and Thermal Properties of a Balanced Canine Food

&#x0D; The structuring of food is mainly done through a complex set of various food materials, such as proteins, polysaccharides, lipids, minerals, and water. Among these components, proteins and polysaccharides are the most used materials in food processing. In extrusion processing, the molecular interactions between its main components play a synergistic role in the achieved structure by performing specific functions in food that affect the sensory, physicochemical, and functional properties. In this research, food for pet animals based on beans (Phaseolus vulgaris L.), fodder corn (Zea mays L.), polished rice (Oryza Sativa), and polysaccharides as inulin, sodium alginate, and/or a native microbial exopolysaccharide from mining waste, was designed and evaluated. To produce the pellet, a single-screw extruder at 140 rpm and 140°C at the exit zone and the effects of the moisture content [13-18%] and concentration of each polysaccharide [0.3-0.9%] on the physicochemical properties of the food were evaluated. The obtained responses were: 1.16-1.4 for expansion index, 0.8-1.7 g/cm3 for bulk density, 1.5-7.4 g/g for water absorption index, 8.8-12.6% for water solubility index, and 8.8-35 N for hardness. According to the recorded values, native exopolysaccharides can provide better physicochemical characteristics than commercial polysaccharides.&#x0D;

Microbiological Quality and Presence of Foodborne Pathogens in Raw and Extruded Canine Diets and Canine Fecal Samples.

Pet food can be a source of microbiological hazards that might affect companion animals and owners. Even though owners usually rely on conventional pet diets, such as extruded diets, new feeding practices, such as raw meat-based diets (RMBDs), have grown. RMBDs' benefits are still scientifically uncertain, while its risks have been documented. The use of canine RMBDs might increase the exposure to zoonotic pathogens, such as Salmonella spp., Listeria monocytogenes, Campylobacter spp., among others. Identifying pathogen prevalence in canine food and pets is required to contribute to public health measures. The aims of this study were: (1) to compare the microbiological quality of RMBDs and extruded diets (2) to identify and compare the prevalence of Salmonella spp., Campylobacter jejuni, and L. monocytogenes from raw and extruded canine diets and canine fecal samples, and (3) to characterize pet owners according to the diet chosen to be used on their pets, their motivations for using RMBDs, and their knowledge about benefits and risks related to this feeding practice. Conventional and molecular microbiological methods were used to identify pathogen presence from food and fecal samples, while pulsed-field gel electrophoresis (PFGE) was performed to evaluate the clonal relationship between isolates. Aerobic plate counts for RMBDs were higher than those detected for extruded diets. Salmonella spp. and L. monocytogenes were isolated from 35.7% (15/42) RMBDs, while Salmonella spp., C. jejuni, and L. monocytogenes from 33.3% (11/33) fecal samples from RMBD-fed dogs. From the RMBD samples positive to Salmonella spp., chicken was the main meat ingredient composing the diets. PFGE analysis confirmed a genetic association between Salmonella spp. isolates from fecal and raw food samples from the same household. We did not detect pathogens from extruded food samples or feces from extruded-fed dogs. Using a survey, we identified dog owners' unawareness and/or underestimation of risks related to RMBDs. We demonstrated that canine raw pet food might be a source of zoonotic foodborne pathogens that represent a health risk for both humans and pets. While clinical findings caused by the mentioned pathogens vary among pets, the zoonotic potential implies a significant concern.

Insect Larvae Meal (Hermetia illucens) as a Sustainable Protein Source of Canine Food and Its Impacts on Nutrient Digestibility and Fecal Quality.

Simple SummaryInsects are considered an optimistic component for animal diets as an alternative to some of the common feedstuffs. Therefore, the present research studied the effect of including black soldier fly larvae meal in a canine diet on nutrient digestibility and fecal quality compared to that of poultry meal. Within this study, it was possible to include the insect larvae meal to replace 30% of dry matter of the basic extruded diet. The research indicated that insect larvae meal showed the highest apparent digestibility for protein and fat without any negative effects on fecal scores, stating it as a potential alternative food ingredient for dogs. These findings suggest that insect larvae meal can be considered a suitable applicable ingredient for canine food that might potentially be included in pet food formulations.Insect larvae meal has been proposed as a sustainable protein source for animal diets. This study aimed to provide information on including black soldier fly larvae meal (BSFL; Hermetia illucens) in comparison to poultry meal (PM) in the canine diet with regard to digestibility and fecal characteristics. In light of this trend, the levels of PM or BSFL meal were added to replace about 30% of dry matter of the basic extruded diet. Six Beagle dogs (BW 9.64 kg) were included in a cross-over experiment. Dogs fed a BSFL meal-based diet showed higher (p < 0.05) apparent protein digestibility (82.3%) compared to those offered a PM-based diet (80.5%). Apparent digestibility for fat was higher (p < 0.05) in groups fed the BSFL meal-based diet (94.5%) compared to those offered the PM-based diet (91.6%). The fecal consistency scores for dogs fed both diets were within an acceptable range (well-formed and firm). Fecal dry matter content was higher (p < 0.05) for dogs fed the PM-based diet (33.0%) compared to those offered the BSFL meal-based diet (28.0%). Including BSFL meal in dog food can be an appropriate source of protein without any negative effects on nutrient digestibility and fecal quality.

Evaluating and re-evaluating intra- and inter-species social transmission of food preferences in domestic dogs

Social-transmission of food preference is a robust behavioral phenomenon in rodents and other species, but less work has evaluated this phenomenon in broader taxa and to what degree social-transmission can occur between species. Here we show that over the span of three experiments that consisted of a human-dog, a dog-dog, and a replication study of a dog-dog demonstrator-observer test, we did not observe successful social transmission of food preferences across all three experiments. For our first experiment, we investigated whether pet dogs acquire food preference from their owners using a two-bowl preference test. The results suggested that our dogs did not acquire a preference for the flavor consumed by their owners. This then led us to investigate whether this failure was the result of an inter-species failure, so we replicated the experiment using two familiar dogs as the demonstrator and observer. The results for Experiment Two also suggested that our participant dogs do not acquire food preference from a canine demonstrator. A third experiment attempted a direct replication of the Lupfer-Johnson and Ross (2007) that found dog-dog transmission of food preferences. Our results again indicated that our participant dogs did not acquire food preference from demonstrators. Over the span of three experiments, our results did not show clear canine food preferences for the food consumed by a demonstrator (human or dog).

The Role of Urine in Semiochemical Communication between Females and Males of Domestic Dog (Canis familiaris) during Estrus.

Simple SummaryCanine reproductive behavior can be easily observed; however, the mechanism of semiochemical signaling in this species is still not well understood. Despite numerous studies, no efficient, artificial canine sex pheromones are available. In most studies of canine semiochemical communication, female urine was believed to be a source of volatile compounds that attract males. We hypothesized that urine is also a source of compounds that are very important in the process of the mating decision but are not so volatile. These compounds are collected by licking urine or the vulva and are transferred into the vomeronasal organ. Such behavior always precedes the male’s mating decision. In two experiments, we assessed the reactions of male dogs in response to air containing odor molecules from estrous females’ urine, from a live female in estrus, and from food, as well as during direct sniffing of urine samples from females in estrus, in anestrus, from male dogs and from humans. It was concluded that urine odor is not used for long-distance semiochemical communication in dogs but rather for close distance signaling.This study aimed to assess the mechanisms of semiochemical signal detection in dogs. In the first experiment, five males were exposed to volatile semiochemicals emitted by a live female in estrus and the female’s urine sample collected during estrus. The odor of canine food and clean air were used as controls. In the second experiment, 25 males could directly sniff and lick the urine samples from females in estrus, from females in anestrus, from males and from humans, placed in a lineup. Sniffing, licking and salivation, as well as keeping dogs at different distances from the source of odor, were recorded in both experiments. Experiment 1 showed that food odor was sniffed by males longer than estrous urine. Volatile semiochemicals from females in estrus evoked interest in males but without visual cues did not cause overt symptoms of sexual arousal. In Experiment 2, the estrous urine evoked interest in males and provoked significantly longer sniffing. Licking accompanied by salivation was observed in all instances only during direct contact with estrous urine. The results suggest a complex character of detection of female reproductive status, in which both volatile and nonvolatile compounds emitted by females and present in female urine are involved.

Canine diet and cutaneous adverse food reactions

The veterinary nurse can play an important role in providing nutritional advice to dog owners. With the wide range of commercial diets that are available, it is important to tailor the diet to each individual animal. Selection of a diet to investigate a cutaneous adverse food reaction (CAFR) should be made after taking a thorough dietary history from the owner and a conversation to decide which diet is most appropriate for each individual. Selection of a diet should involve the use of a novel or hydrolysed protein source for that dog, but other factors such as palatability, convenience, nutritional content and cost need also to be considered. If a diet is carefully matched to owner and pet requirements, the chances of good owner compliance and a response to the diet can be maximised.

Dogs as a source of Salmonella spp. in apparently healthy dogs in the Valencia Region. Could it be related with intestinal lactic acid bacteria?

BackgroundAlthough salmonellosis is considered one of the most important food-borne zoonotic diseases in Europe, close contact between dogs and their owners can also be a potential source of Salmonella spp. for humans. This study assessed the prevalence and antimicrobial resistance of Salmonella spp. in apparently healthy dogs in the Valencian Region, eastern Spain. Moreover, a macroscopic comparison of lactic acid bacteria in both Salmonella-positive and Salmonella-negative dogs was carried out.ResultsOf a total of 325 dogs sampled, 6 (1.85%) were positive for Salmonella spp. with 3 different serotypes, Havana (3), Mikawasima (2) and monophasic Typhimurium (1). All isolates were susceptible to all antimicrobials tested except monophasic S. Typhimurium, which was resistant to ampicillin. Finally, macroscopic results revealed that lactic acid bacteria had higher heterogeneity in the Salmonella-negative dogs than in the Salmonella-positive dogs. Although the results in our study showed a low prevalence of Salmonella spp., raw food has been suggested as a risk factor for bacteria in dog faeces.ConclusionsPublic awareness campaigns on good hygiene practices, especially after handling canine faeces or raw food, are necessary. Furthermore, to reduce the potential transmission of bacteria, dogs should be fed food that has been properly cooked, as raw or undercooked food can be a source of zoonotic pathogens. Moreover, further studies must be performed to determine the relationship between lactic acid bacteria and Salmonella spp. in dog faeces.

Are Underweight Shelter Dogs More Likely to Display Food Aggression toward Humans?

Simple SummaryCanine aggression over resources such as food or edible chews is commonly termed food guarding or food aggression. Food aggression directed at humans is relatively common in dogs, including dogs that enter animal shelters. While food aggression is part of dogs’ normal behavior, little is known about why some dogs show food aggression, but others do not. Common animal shelter “lore” suggests that dogs that are underweight or were previously starved are more likely than normal-weight dogs to show aggression toward a human that approaches while the dog is eating. It is assumed that the value of food to the dog is increased by experience with food scarcity, and the value remains elevated even after food is no longer scarce. We tested this common belief by analyzing data from 900 dogs from criminal cruelty cases to look for a relationship between the dogs’ weight and human-directed food aggression. Contrary to common belief, we found that underweight dogs were not more likely than normal-weight dogs to be food aggressive. Based on these results, human-directed food aggression is not a reliable indicator of past food scarcity. This has implications for criminal proceedings, as dogs can have previously experienced starvation without obvious residual behavioral indications in the shelter.It is commonly believed that underweight or emaciated dogs are predisposed to food aggression toward humans. Each year, the American Society for the Prevention of Cruelty to Animals (ASPCA) receives hundreds of dogs from criminal cruelty cases. The dogs range from emaciated to overweight. We analyzed existing data from 900 such dogs to examine the relationship between body condition score and food and chew item aggression toward humans. Across all types of cruelty cases, 9.2% of dogs were aggressive over the food, chew, or both, which is a lower prevalence than that previously reported among shelter dogs. Dogs from cruelty cases originating in New York City were more likely to show aggression over food (z = 3.91, p < 0.001) and chew items (z = 2.61, p = 0.01) than dogs from large-scale cruelty cases, although it is unclear why. Female dogs were less likely to show food (z = −3.75, p < 0.001) and chew item (z = −2.25, p = 0.02) aggression compared to males. Underweight dogs were not more likely to display food aggression, but when they did, the aggression was no more severe than that of normal-weight dogs (Fisher’s exact tests = 0.41 and 0.15 for the Food Bowl and Chew Item scenarios, respectively). Breed type was not a significant predictor of aggression. Canine food aggression does not appear to be an aberrant behavior caused by a history of food scarcity but may be related to biological factors such as sex. These findings could prove useful for animal behavior subject matter experts testifying in court or consulting on cruelty cases, as they could speak with scientific validity to the question of whether there is a link between previous food scarcity and the likelihood of food aggression in dogs.

Diets containing naturally occurring iron or naturally occurring iron plus supplemental ferrous sulfate both maintain normal hematological status in adult dogs

Iron is an essential mineral for dogs due to its roles in physiological processes. The NRC recommends the adequate intake for iron in adult dogs is 0.5 mg/kg of body weight. While iron should be present in high enough concentrations in the diet to maintain normal hematological status and prevent iron deficiency anemia, too much dietary iron can increase lipid oxidation in the food during preparation and storage, subsequently reducing shelf life, palatability, and nutritional content of foods. In general, iron is supplemented to diets to ensure that no dogs are deficient. The primary objective of this study was to investigate the ability of a diet containing either 0 mg/kg or 80 mg/kg supplemental iron to support normal hematological parameters in adult dogs. Twenty-two adult dogs were randomly assigned to one of two treatment diets: Test Diet 1, Experimental maintenance formula with 115 mg/kg endogenous iron + 0 mg/kg supplemental iron; and Test Diet 2, Experimental maintenance formula with 115 mg/kg endogenous iron + 80 mg/kg supplemental iron (ferrous sulfate). Dogs consumed treatment diets for 26 weeks, with clinical assessments (e.g., hemoglobin concentration/total iron binding capacity) assessed throughout the trial (0, 2, 4, and 6 months). Baseline iron related endpoints were not different between diet treatments (P &gt; 0.50), except for mean corpuscular hemoglobin concentrations (P = 0.046). No differences were found for iron related end points between the two diet treatments (P&gt;0.05) at any time point. In some diets no supplemental iron will be needed, based on the diet matrix, whereas others may require some supplemental iron. By reducing iron inclusion in the formulations of canine diets, food stability and shelf life may be improved. This reduction in supplemental iron can also reduce cost of formulation, benefiting food manufacturers, consumers, and adult dogs.

Effect of Lipid Contents and Process Parameters on the Physicochemical, Rheological, Calorimetric and Structural Properties of an Extruded Canine Food

Effect of Lipid Contents and Process Parameters on the Physicochemical, Rheological, Calorimetric and Structural Properties of an Extruded Canine Food

Hypersensitivity in a dog accompanied by generalised onychodystrophy

Canine food hypersensitivity and canine atopic dermatitis are two of the most common allergic diseases in dogs. Food hypersensitivity is typically non-seasonal reaction of types I, III and IV, directed most commonly against glycoproteins in the foods. Canine atopic dermatitis is a genetically predisposed inflammatory and pruritic allergic skin disease with characteristic clinical features associated with IgE most commonly directed against environmental allergens. Irrespective of allergens that dogs are sensitised to, clinical symptoms in acute cases involve pruritus with erythema of the skin around lips, axillae, inguinal and perianal region or feet as well as external ear canal inflammation. In chronic cases, consequences of self-trauma and secondary bacterial or fungal infections may be present as excoriations, lichenification and hyperpigmentation. Hypersensitivity can have a strong impact on quality of life of diseased dogs as well as of their owners. A mixed breed female dog with heavily expressed generalised onychodystrophy accompanied by mild erythema of the groin and external ear canals, which responded to elimination diet and allergen-specific immunotherapy, is presented.

Differentiating between food bloat and gastric dilatation and volvulus in dogs

Gastric dilatation and volvulus (GDV) is a surgical emergency in dogs which has been extensively studied, with virtually all aspects of patient management reviewed and examined. Breed predisposition,1 risk factors...

Canine Food Preference Assessment of Animal and Vegetable Ingredient-Based Diets Using Single-Pan Tests and Behavioral Observation.

Knowledge of canine food selection is critical for both the pet food industry and dog owners, since owners want quality foods that are palatable, while fulfilling their pet’s nutritional requirements. There are two common methods for assessing canine food preference: the two-pan test and the one-pan test. Neither test fully accounts for the complexity of the canine feeding experience nor do they provide applicable representations of canine feeding behavior in the home. The objectives of this study were to (1) determine whether dogs display a preference for animal ingredient-based diets when compared with vegetable ingredient-based diets and (2) examine whether dogs experience neophobia when presented with a novel diet. Eight adult Beagles (average age = 24 months, weighing 8–12 kg) were individually fed each of four novel diets in a 4 × 4 replicated Latin square design, with 10-d treatment periods and four dietary treatments. Data were analyzed using a mixed model with repeated measures and significance was declared when p < 0.05. The diets were: animal and vegetable ingredient-based diets, and animal- and vegetable-based ingredients diluted with anhydrous α-d-glucose. The diluted diets were used for a larger study to determine true mineral digestibility. Dogs were fed twice per day (0800 and 1300 h). Behavioral observations were made by video on the first, and last 2 days of each 10-day treatment period of both a.m. and p.m. feedings. Time to consume feed, distraction, hesitation, level of anticipation pre-consumption, and interest post-consumption were recorded. Dogs experienced initial disruptive (neophobic) effects of a novel diet. Neophobia was demonstrated by a decreased (slower) rate of consumption, increased distraction during consumption of the diet, and increased hesitation on the first day of each new diet (p < 0.05). The level of interest post-consumption was highest when dogs consumed the animal-based ingredients diet (p < 0.05). This study presents insights into canine food preference assessment methods that may more accurately represent the dog owner’s experience. Further research is required to determine the minimum length of time necessary to eliminate neophobia to food. In addition, future research should also aim to establish whether interest post-consumption is due primarily to food preference or acute satiety.

Canine atopic dermatitis and adverse food reactions

Hilary Jackson, co-editor of the BSAVA Manual of Canine and Feline Dermatology, takes companion readers through the diagnosis and treatment of canine atopic dermatitis, including the importance of ruling out adverse food reactions.

Safety assessment of potential food ingredients in canine hepatocytes

This research aimed to develop in vitro methods to assess hazard of canine food ingredients. Canine hepatocytes were harvested and cell viability of clove-leaf oil (CLO), eugenol (EUG), lemongrass oil (LGO), guanosine monophosphate (GMP), inosine monophosphate (IMP), sorbose, ginger-root extract (GRE), cinnamon-bark oil (CBO), cinnamaldehyde (CINA), thymol oil (TO), thymol (THYM), and citric acid were assessed with positive controls: acetaminophen (APAP), aflatoxin B1 and xylitol. Molecular Toxicology PathwayFinder array (MTPF) analyzed toxicity mechanisms for LGO. LC50 for APAP was similar among human (3.45), rat (2.35), dog (4.26 mg/ml). Aflatoxin B1 had an LC50 of 4.43 (human), 5.78 (rat) and 6.05 (dog) µg/ml; xylitol did not decrease viability. LC50 of CLO (0.185 ± 0.075(SD)), EUG (0.165 ± 0.112), LGO (0.220 ± 0.012), GRE (1.54 ± 0.31) mg/ml; GMP (166.03 ± 41.83), GMP + IMP (208.67 ± 15.27) mM; CBO (0.08 ± 0.03), CINA (0.11 ± 0.01), TO (0.21 ± 0.03), THYM (0.05 ± 0.01), citric acid (1.58 ± 0.08) mg/ml, while sorbose was non-toxic. LGO induced upregulation of 16 and down-regulation of 24 genes, which CYP and heat shock most affected. These results suggest that in vitro assays such as this may be useful for hazard assessment of food ingredients for altered hepatic function.