Correction: Atuahene et al. A Supplement with Bromelain, Lentinula edodes, and Quercetin: Antioxidant Capacity and Effects on Morphofunctional and Fecal Parameters (Calprotectin, Cortisol, and Intestinal Fermentation Products) in Kennel Dogs. Vet. Sci. 2023, 10, 486.

There was an error in the original publication [...].

The Canine Gut Health: The Impact of a New Feed Supplement on Microbiota Composition.

This study aimed to determine the impact of a novel formulation of a supplement composed of the natural ingredients, bromelain, quercetin, and Lentinula edodes, on the gut microbiota of healthy adult dogs. Adult healthy female dogs were administered either a placebo (CTR, n = 15) or the supplement (TRT, n = 15) over 28 days. Stool samples were collected for 16S rRNA sequencing before supplement administration (T0), at completion of supplement administration (T28), and one week after the end of supplement administration (T35) to characterize changes in the gut microbial communities. QIIME was used to determine both alpha- and beta-diversity, and ANCOM-BC was used to identify differences in taxonomic abundances before and after supplementation. We found a significant decrease in overall diversity in the CTR group but no significant differences in overall diversity in the TRT group over time. Furthermore, we found differences in the abundance of several taxa in both the CTR and TRT groups, but differences in the abundance of beneficial bacteria were more pronounced in the TRT group. Specifically, we found increases in the abundance of sequences belonging to the genera Bifidobacterium, Lactobacillus, and Pediococcus at T28 in the TRT group with significant increases in Bifidobacterium and Lactobacillus persisting at T35 when compared to T0. Importantly, members of these genera are considered important for their anti-inflammatory properties, vital for fostering a balanced and robust gut microbiota in dogs. The results of our study show the potential of our supplement to selectively enhance specific beneficial bacterial taxa, offering a targeted approach to modulating the gut microbiome without causing disruptions to the overall equilibrium.

Supplementation with Silybum marianum Extract, Synbiotics, Omega-3 Fatty Acids, Vitamins, and Minerals: Impact on Biochemical Markers and Fecal Microbiome in Overweight Dogs.

Overweight and obese dogs can develop metabolic dysfunction, characterized by an inflammatory response and involvement of liver functions. If a modulation of the gut microbiome and its interaction with the gut-liver axis is implicated in the development of metabolic dysfunction, exploration becomes necessary. Over the past decade, diverse therapeutic approaches have emerged to target pathogenic factors involved in metabolic dysfunction. This study investigated the impact of a supplement with hepatoprotective activity, containing extracts of Silybum marianum, prebiotics, probiotics, n-3 polyunsaturated fatty acids, vitamins, and minerals on hematological markers of liver functions and inflammation, as well as on the intestinal microbiota of 10 overweight adult dogs over a 35-day time span. Animals underwent clinical and laboratory evaluations every 7 days, both before the administration of the supplement (T0) and after 7, 14, 21, 28, and 35 days (T1, T2, T3, T4, and T5). In comparison to T0, a significant (p < 0.05) decrease in ALP, glucose, direct bilirubin, and CRP was observed from T3 to T5. The alpha diversity of the fecal microbiota significantly decreased (p < 0.05) only at T1, with high variability observed between dogs. Total short-chain fatty acid and lactic acid were also lower at T1 (p < 0.05) compared to the other times of sampling. The beta diversity of the fecal microbiota failed to show a clear pattern in relation to the sampling times. These results of blood parameters in overweight dogs show a reduction of the inflammation and an improvement of metabolic status during the study period, but the effective contribution of the supplement in this clinical outcome deserves further investigation. Furthermore, the considerable individual variability observed in the microbiome hinders the confident detection of supplement effects.

A Supplement with Bromelain, Lentinula edodes, and Quercetin: Antioxidant Capacity and Effects on Morphofunctional and Fecal Parameters (Calprotectin, Cortisol, and Intestinal Fermentation Products) in Kennel Dogs.

Oxidative stress causes several pathological conditions in humans and animals, including gastrointestinal disorders. The aim of this study was to analyze the antioxidant capacity of three natural powdered raw materials containing quercetin, bromelain, and Lentinula edodes and develop a new feed supplement for dogs using a combination of them. The total phenolic content (TPC), antioxidant activity, DPPH (2,2-diphenyl-1-picrylhydrazyl), and ABTS (2,2'-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt) of the extracts, either individually or in combination, were evaluated colorimetrically. The effects of this supplement on healthy adult dogs' nutritional, inflammatory, and stress status were evaluated. American Staffordshire Terrier adult female dogs (n = 30) were randomly assigned to a control (n = 15) or a treated (n = 15) group. The supplement was added as powder to the food of the treated dogs once daily for 28 days. There was no significant difference in the body weight and body condition scores between the initial and final phases of the experiment. At the end of our study, a significant decrease in fecal calprotectin, cortisol, indole/skatole, and N-methylhistamine and a significant increase in short-chain fatty acids were observed as compared to the control group. In conclusion, this natural feed supplement can be used to improve gastrointestinal health and psycho-physical conditions in dogs.

Effect of an Enteroprotective Complementary Feed on Faecal Markers of Inflammation and Intestinal Microbiota Composition in Weaning Puppies.

Weaning entails numerous modifications of the intestinal structure and microbiota composition, making puppies at high risk of sickness during this delicate life stage. The aim of this study was to investigate the effects of a four-week administration of a supplement composed of ultramicronised Palmitoylethanolamide, bovine colostrum and Bacillus subtilis (Normalia® Extra, Innovet Italia Srl, Saccolongo, Italy) on markers of gut health and microbiome of weaning puppies. Twenty-nine four-week-old Golden Retriever puppies were randomly assigned to control (CG, n = 13) and treated (TG, n = 16) groups. During the whole experimental time, there were no differences between the groups with regard to average daily gain and faecal score. In TG, faecal calprotectin and zonulin values were statistically significantly decreased compared to CG, especially at week 8 (zonulin: 42.8 ± 1.54 ng/mL and 55.3 ± 42.8 ng/mL, and calprotectin: 2.91 ± 0.38 µg/g and 5.71 ± 0.43 µg/g, in TG and CG, respectively; p < 0.0001 for both comparisons). Bacteria belonging to phylum Campylobacterota decreased (p = 0.04), while those referring to genera Coprococcus and Pseudomonas increased (p = 0.01 and p = 0.04, respectively). The supplementation of the tested complementary feed can promote the intestinal health of puppies and therefore facilitate weaning by lowering gut inflammation.

Characterization of the Blood Microbiome and Comparison with the Fecal Microbiome in Healthy Dogs and Dogs with Gastrointestinal Disease.

Recent studies have found bacterial DNA in the blood of healthy individuals. To date, most studies on the blood microbiome have focused on human health, but this topic is an expanding research area in animal health as well. This study aims to characterize the blood microbiome of both healthy dogs and those with chronic gastro-enteropathies. For this study, blood and fecal samples were collected from 18 healthy and 19 sick subjects, DNA was extracted through commercial kits, and the V3-V4 regions of the 16S rRNA gene were sequenced on the Illumina platform. The sequences were analyzed for taxonomic annotation and statistical analysis. Alpha and beta diversities of fecal microbiome were significantly different between the two groups of dogs. Principal coordinates analysis revealed that healthy and sick subjects were significantly clustered for both blood and fecal microbiome samples. Moreover, bacterial translocation from the gut to the bloodstream has been suggested because of found shared taxa. Further studies are needed to determine the origin of the blood microbiome and the bacteria viability. The characterization of a blood core microbiome in healthy dogs has potential for use as a diagnostic tool to monitor for the development of gastro-intestinal disease.

Antioxidant Effect of a Dietary Supplement Containing Fermentative S-Acetyl-Glutathione and Silybin in Dogs with Liver Disease.

Oxidative stress is often involved in liver disease progression. Liver is the primary site for the synthesis of glutathione (GSH), the major intracellular antioxidant. GSH erythrocyte concentration can decrease in case of liver damage. So, the use of food supplements with antioxidant capacity has been reported in the veterinary literature. In this case-control study, we tested a new supplement containing S-acetyl-glutathione (SAG), silybin, and other antioxidant ingredients in dogs affected by liver disease. After two weeks of supplement administration, we were able to report a significant increase in the level of erythrocyte GSH in the treated (TRT) group, nearly reaching the physiological limit at the end of the study. In addition, most of the key liver parameters are significantly reduced in the TRT group by the end of the trial. The results of this study support the effectiveness of the tested complementary feed, which may be helpful in managing dogs with liver conditions.

Circulating and endometrial cell oxidative stress in dairy cows diagnosed with metritis.

Dairy cows diagnosed with metritis may experience a greater degree of oxidative stress (OS) and a deficit in the antioxidative capacity compared to healthy cows. We aimed to assess circulating OS markers and endometrial cell mitochondrial function, intracellular reactive oxygen species (ROS) production, and mean endometrial nuclear cell area in postpartum cows diagnosed with metritis or as healthy. From an initial pool of 121 Holstein cows, we retrospectively selected 34 cows and balanced for metritis (n = 17) or healthy (n = 17). Metritis was defined as an enlarged uterus with red-brown watery or thick off-white purulent discharge occurring within 21 days postpartum. Cows with no signs of clinical disease (including dystocia or retained placenta) were referred to as healthy. Blood samples for serum reactive oxygen metabolites (d-ROM), antioxidants (OXY), and oxidative status index (OSI) tests, evaluated via photometric determination of plasma thiols, were performed at 7, 14, 21, 28, and 35 days postpartum. Furthermore, from the initial pool, a random subset of 5 cows diagnosed with metritis and 6 diagnosed as healthy we collected (at the same time points as for the blood samples) endometrial cytology samples using the cytobrush technique. From the uterine samples, we evaluated the endometrial cell mitochondrial function, intracellular ROS levels, and the endometrial cell nuclear area using MitoTracker Orange, dichlorodihydrofluorescein diacetate, and Hoechst 33258, respectively. Mixed linear regression models, accounting for repeated measurements, were fitted to assess the effect of metritis versus healthy on circulating and endometrial cell OS parameters and endometrial cell size. The effect of days postpartum and its interaction with uterine health status were forced into each model. Serum concentrations of d-ROMs and OSI were greater in metritis at 7, 14, and 35 days postpartum than in healthy cows. Interestingly, the mean endometrial cell nuclear area was lower in metritis than healthy cows at 14 and 21 days postpartum. We found no differences between metritis and healthy for endometrial cell mitochondrial function and intracellular ROS production. In conclusion, cows diagnosed with metritis experienced greater systemic OS levels than healthy cows, but their OS was not higher in the uterine milieu.

Long-term effects of a diet supplement containing Cannabis sativa oil and Boswellia serrata in dogs with osteoarthritis following physiotherapy treatments: a randomised, placebo-controlled and double-blind clinical trial.

Dogs are commonly affected by Osteoarthritis (OA). Different approaches can be used to alleviate animals' symptoms. In this randomised, placebo-controlled and double-blind clinical trial, we performed a three months follow-up study assessing the efficacy of a food supplement containing natural ingredients (Cannabis sativa oil, Boswellia serrata Roxb. Phytosome® and Zingiber officinale extract) in dogs with OA after the interruption of physiotherapy that was performed during the previous three months. Inflammation and oxidative stress were reduced in the treated group (higher glutathione (GSH) and lower C-reactive protein [CRP] levels in blood) as well as chronic pain.

Effects of Saccharomyces boulardii Supplementation on Nutritional Status, Fecal Parameters, Microbiota, and Mycobiota in Breeding Adult Dogs.

The aim of this study was to evaluate the effect of the administration of Saccharomyces boulardii on the nutritional, immunological, inflammatory, and stress status and on the composition of the gut microbiota and mycobiota in healthy adult dogs. A total of 25 American Staffordshire Terrier dogs were selected and randomly assigned to two groups: control (CTR, n = 12) and treated (TRT, n = 13) groups. No significant differences were found between the two groups regarding body weight, body condition score, and fecal score. No significant differences in microbiota/mycobiota, short chain fatty acids, indole/skatole, histamine, zonulin, or lactoferrin were detected. Indeed, supplementation with S. boulardii significantly decreased fecal calprotectin Immunoglobulin A, indicating an improvement in the gut well-being. Interestingly, fecal cortisol significantly decreased in dogs belonging to the TRT group compared to the CTR, suggesting both an improvement of the intestinal status and a reduction of stress, a common condition affecting animals managed in a breeding environment.

Chronic Intestinal Disorders in Humans and Pets: Current Management and the Potential of Nutraceutical Antioxidants as Alternatives.

Chronic intestinal disorders (CID) are characterized by persistent, or recurrent gastrointestinal (GI) signs present for at least three weeks. In human medicine, inflammatory bowel disease (IBD) is a group of chronic GI diseases and includes Crohn's disease (CD) and ulcerative colitis (UC). On the other hand, the general term chronic enteropathies (CE) is preferred in veterinary medicine. Different therapeutic approaches to these diseases are used in both humans and pets. This review is focused on the use of traditional therapies and nutraceuticals with specific antioxidant properties, for the treatment of CID in humans and animal patients. There is strong evidence of the antioxidant properties of the nutraceuticals included in this review, but few studies report their use for treating CID in humans and none in animals. Despite this fact, the majority of the nutraceuticals described in the present article could be considered as promising alternatives for the regular treatment of CID in human and veterinary medicine.

Efficacy of a dietary supplement in dogs with osteoarthritis: A randomized placebo-controlled, double-blind clinical trial.

This study is a randomized, placebo-controlled, double-blinded trial performed to investigate the effects of a dietary supplement containing a mixture of Boswellia serrata Roxb., chlorophyll, green tea extract, glucosamine, chondroitin sulfate, hyaluronic acid, and further in the manuscript: non-hydrolised type II collagen in dogs with osteoarthritis (OA). A total of 40 dogs were enrolled in the study, they were randomly divided in control (CTR) and treatment (TRT) groups. The TRT group received the dietary supplement for 60 days. The CTR group received a placebo for the same number of days. All the subjects had veterinary evaluations during the trial and owners were requested to fill in questionnaires on chronic pain using the Helsinki Chronic Pain Index. The product was easy to administer and no side effects were reported. Combining results from veterinarian and owner evaluations, the tested product proved to be significantly beneficial in alleviating pain and in reducing the clinical signs in dogs with OA.

Chronic Kidney Disease and Dietary Supplementation: Effects on Inflammation and Oxidative Stress.

Chronic kidney disease (CKD) causes an irreversible loss of kidney functioning in dogs. This double-blind case-control study evaluates the efficacy of a dietary supplement, which contains calcium carbonate, calcium lactate-gluconate, chitosan, sodium bicarbonate, Lactobacillus acidophilus D2/CSL, Olea europaea L. extract, and fructooligosaccharides, in dogs in advanced CKD stage. Thirty dogs were enrolled in the study; half were administered the new dietary supplementation for 90 days, while the others were used as controls. Hematologic, biochemical, and urinalysis were performed. This novel dietary supplement mainly reported a good control of uremia, phosphate, acid-base balance, blood pressure, inflammation, and oxidative stress in dogs with advanced stages of CKD.

Protective Effect of Natural Antioxidant Compounds on Methimazole Induced Oxidative Stress in a Feline Kidney Epithelial Cell Line (CRFK).

The treatment of choice for feline hyperthyroidism is the administration of the antithyroid drug methimazole. Both the endocrinopathy and the drug adverse reactions (e.g., hepatotoxicosis, gastrointestinal disorders, and renal injury) are partly due to oxidative stress and redox unbalance. This study investigated the free radical production and the impairment of the antioxidant barrier induced by methimazole in an in vitro model of feline renal epithelium. The protective effects of quercetin and resveratrol were also explored. CRFK cells were incubated with a methimazole concentration equivalent to the maximum plasma levels in orally treated cats (4 µM), in the presence or absence of either one of the two selected antioxidants at different time-points (up to 72 h). Cell viability, ROS production, GSH levels, and mRNA expression of antioxidant enzymes (i.e., CAT, SOD, GPx, and GST) were assessed. Methimazole impaired cell viability and increased ROS levels in a time-dependent manner. Similarly, GSH content and CAT, SOD, and GPx3 expression were higher compared with control cells. Such effects were significantly counteracted by quercetin. These results provide new insights about the mechanisms underlying the methimazole-related side effects frequently observed in hyperthyroid cats. They also support the use of quercetin in the management of feline hyperthyroidism.

Management of Feline Hyperthyroidism and the Need to Prevent Oxidative Stress: What Can We Learn from Human Research?

Feline hyperthyroidism is a clinical syndrome related to an excessive production of thyroid hormones, and it is considered as a spontaneous animal model for human thyrotoxicosis. Many shared features between the feline and the human disease have been identified so far, including pathogenesis, clinical signs, and treatment options. Although methimazole is considered the first-choice drug in both species, several side effects have been described. Furthermore, methimazole could interfere with the oxidative status, already perturbated by the disease. It has been reported in humans that dietary management, mainly through antioxidant supplementation, could mitigate this oxidative burden. The purpose of the review is to describe current therapeutic options in the course of feline hyperthyroidism and to summarize the state of the art relationship between dietary antioxidants administration and the reduction of methimazole side-effects in humans to support the use of this approach also in cats.

Amaranthus hypochondriacus L. as a Sustainable Source of Nutrients and Bioactive Compounds for Animal Feeding.

With the aim to explore the use of A. hypochondriacus seeds for animal feeding, the agronomic traits, nutrients, and bioactive compounds of four accessions with different origin (India, Nebraska, Iowa, and Pennsylvania) grown in a Mediterranean environment were studied. Proximate composition was determined using the official methods of analyses, fatty acid profile by gas chromatography, total phenolic content (TPC) and the scavenging activity (DPPH• and ABTS•+) by colorimetric method. A one-way ANOVA model was performed to determine the differences between accessions. The four A. hypochondriacus accessions showed interesting seed yield results. No significant differences were observed for crude protein and crude fiber; the oil content showed the significant highest values in the seeds from Nebraska and Pennsylvania, but their nutritional characteristics were significantly different. The accession from Nebraska showed the highest oleic and linoleic acid levels, the highest values of polyunsaturated fatty acids, the best atherogenic and thrombogenic indices and hypocholesterolemic/hypercholesterolaemic ratio, and the highest TPC content. The accession from Pennsylvania showed the highest antioxidant activity and lowest peroxidation index. On the whole, A. hypochondriacus seeds can be used as pseudo-cereal to balance the animal diet and the accession should be chosen according to the different metabolic pathways of unsaturated fatty acids in ruminant and monogastric animals.

Effects of "fresh mechanically deboned meat" inclusion on nutritional value, palatability, shelf-life microbiological risk and digestibility in dry dog food.

Fresh mechanically deboned meat (MDM) is usually claimed as high-quality ingredient on dry pet food recipes and this aspect may positively influence consumer choice. It is important to determine the scientifically sustainability of this claim and to assess the microbiological safety of MDM inclusion in dry pet food. Objectives were: 1) to evaluate the effect of inclusion of MDM in dry dog food on fatty acid profile and in vivo and in vitro digestibility, proposing a new system (DaisyII Incubator) to measure the in vitro digestibility for dogs; 2) to compare palatability of dry dog food containing MDM with dry dog food in which meat by-products (MBP) are the only animal protein sources; 3) to determine, whether or not, the inclusion of that ingredient changes the microbiology and the storage quality. Results indicated that MDM product was characterized by significant higher nutritional value in terms of fatty acids profile, in vitro digestibility (HV-IVD method) and lower palatability than the MBP product. Microbiological risk assessment showed no microbiological hazards for either product. After 6-months storage, the total mesophilic bacterial count ranged between 1.77 and 2.09 log CFU/g feed, while polyamine values were higher in the MDM (0.37 g/kg) than in the MBP (0.27 g/kg). The DaisyII Incubator was found to be a valid instrument for studying in vitro digestibility also for dogs, providing data simply, quickly, with less variability and costs than in vivo trials. In conclusion, MDM inclusion in dry dog food is microbiologically safe and it can improve its nutritional quality, at the expense of a reduced palatability. The higher polyamine levels fount in MDM-enriched petfood after 6-months storage, however, may represent a possible hazard, and further studies are still warranted.

Strategies to expand the therapeutic potential of superoxide dismutase by exploiting delivery approaches.

The overproduction of free radicals can cause oxidative-stress damage to a range of biomolecules, and thus potentially contribute to several pathologies, from neurodegenerative disorders to cardiovascular diseases and metabolic disorders. Endogenous antioxidant enzymes, such as superoxide dismutase (SOD), play an important role in diminishing oxidative stress. SOD supplementation could therefore be an effective preventive strategy to reduce the risk of free-radical overproduction. However, the efficacy of SOD administration is hampered by its rapid clearance. Several different approaches to improve the bioavailability of SOD have been explored in recent decades. This review intends to describe the rationale that underlie the various approaches and chemical strategies that have led to the most recent advances in SOD delivery. This critical description includes SOD conjugates, SOD loaded into particulate carriers (micelles, liposomes, nanoparticles, microparticles) and the most promising and suitable formulations for oral delivery, with a particular emphasis on reports of preclinical/clinical results. Likely future directions are also considered and reported.

State-of-the-Art of the Nutritional Alternatives to the Use of Antibiotics in Humans and Monogastric Animals.

In recent years, the indiscriminate use of antibiotics has been perpetrated across human medicine, animals destined for zootechnical productions and companion animals. Apart from increasing the resistance rate of numerous microorganisms and generating multi-drug resistance (MDR), the nonrational administration of antibiotics causes sudden changes in the structure of the intestinal microbiota such as dysbiotic phenomena that can have a great clinical significance for both humans and animals. The aim of this review is to describe the state-of-the-art of alternative therapies to the use of antibiotics and their effectiveness in humans and monogastric animals (poultry, pigs, fish, rabbits, dogs and cats). In particular, those molecules (probiotics, prebiotics and postbiotics) which have a direct function on the gastrointestinal health are herein critically analysed in the prevention or treatment of gastrointestinal diseases or dysbiosis induced by the consumption of antibiotics.

Productive and Qualitative Traits of Amaranthus Cruentus L.: An Unconventional Healthy Ingredient in Animal Feed.

Agronomic traits, oil content, fatty acid composition, antioxidant activity, and total phenolic content were studied on eight A. cruentus accessions cultivated in Southern Italy. A one-way ANOVA model was performed to compare accessions and the Principal Components Analysis was applied to identify patterns in our dataset and highlight similarities and differences. A. cruentus showed valuable seed yield (0.27 kg/m2, on average) comparable to the main tradition cereals used for animal feeding. Seed-oil composition showed significant differences among the accessions. Data showed a higher lipid content than most cereal grains (from 5.6 to 7.3%). Approximately 60% of fatty acids were unsaturated; linoleic fatty acid ranged from 19 to 34%, oleic acid from 29 to 36%, and alfa-linolenic fatty acid from 0.3 to 0.5%, respectively. The saturated/unsaturated fatty acid ratio ranged from 0.5 to 0.8, the hypocholesterolemic:hypercholesterolaemic ratio from 1.7 to 2.7, the Atherogenic Index from 0.38 to 0.66, the Thrombogenic Index from 0.85 to 1.48, the total phenolic content from 0.14 to 0.36 mg/g seeds, and the antioxidant activity (DPPH•) from 0.30 to 0.50. The studied seed-oil composition evidenced A. cruentus as a healthy ingredient for animal feed and consequently, as a possible substitute for traditional cereals. Accessions from Mexico and Arizona emerged for their high qualitative traits.