Effects of black soldier fly larvae as protein or fat sources on apparent nutrient digestibility, fecal microbiota, and metabolic profiles in beagle dogs

Evaluation of the Nutritional Value of Insect-Based Complete Pet Foods

Since the legalization of insect protein in pet food, a variety of products incorporating this ingredient have emerged on the market. Although edible insects are acknowledged for high protein content, chitin can also elevate the quantity of indigestible carbohydrates. The objective of this study was to evaluate the nutritional adequacy of fourteen complete dog foods containing edible insects in accordance with the FEDIAF nutritional guidelines. Due to the use of insects as the predominant animal component in all diets, analyses of dietary fiber fractions were carried out to estimate the content of indigestible carbohydrates. The analyses included the assessment of chemical composition, calcium, and phosphorus levels and metabolizable energy. The findings were then compared with the data provided by the manufacturers. All diets were found to meet the minimum recommended levels from the FEDIAF nutritional guidelines for protein (18.0 g/100 g DM) and fat (5.5 g/100 g DM). However, discrepancies were noted between the label data and analysis results. The results for the dietary fiber fraction differed from the crude fiber content, which is consistent with the imprecision inherent to the crude fiber determination method. In one food, there was a discrepancy of up to 19.21 g between the NDF fraction and the crude fiber content. Calcium levels were inadequate in two foods, and furthermore, twelve foods exhibited an abnormal calcium/phosphorus ratio. These findings indicate that while edible insects can be a valuable protein source, their inclusion may lead to increased indigestible carbohydrates, potentially causing digestive issues and gastric discomfort in dogs.

Assessing pet owners' willingness to embrace insects in pet food

Alternative diets for pets have gained attention in recent years due to concerns about sustainability and environmental impact. One emerging option is the inclusion of edible insects in pet food. This study aimed to survey dog (DO) and cat (CO) owners regarding their willingness to feed insect-based pet food (IBPF) to their pets and to identify potential motivating factors. A total of 435 valid responses were evaluated, with 66% being DO and 58% CO. Of those, 24% owned both dogs and cats. About half of DO (52%) and 62% of CO were positive about IBPF. CO had a higher acceptance of IBPF than DO (p < 0.05). Moreover, both DO and CO showed a significant increase in acceptance if IBPF has been proven to provide sustainable and nutritional benefits (p < 0.01). CO adhering to a specific diet themselves showed a significantly higher acceptance of IBPF (p < 0.05), however it was independent of the type of diet. Additionally, 32% of DO and 34% of CO reported prior experience with eating edible insects themselves, and a positive entomophagy experience increased DO's (p = 0.108) and CO's (p < 0.01) acceptance of IBPF. Furthermore, the interest in entomophagy resulted in increased acceptance of IBPF by both DO and CO who had not yet tried insects (p < 0.01). In conclusion, pet owners demonstrated a favourable perception of IBPF and showed a willingness to incorporate these products into their pets' diets. CO displayed a more positive perception compared to DO, suggesting a beneficial focus on the feline niche. To enhance overall acceptance, emphasizing sustainability and conducting further research to establish the nutritional benefits of IBPF are crucial. The findings of this study provide valuable insights for pet food manufacturers and marketers to develop strategies and products aligned with the preferences and needs of pet owners.

Effects of Different Processed Diets on Growth Performance, Blood Parameters, Hair Quality and Fecal Microbiota in Ragdoll Cats

In recent years, there has been ongoing debate about the dietary choices for pet cats, particularly regarding three options: extruded dry food, cooked meat, and raw meat. Determining which diet is most suitable for a cat's healthy growth still requires substantial empirical support. Our study aimed to evaluate the effects of feeding Ragdoll cats (n = 5/group) extruded dry food (ED), cooked meat (CM), and raw meat (RM) on their growth performance, apparent digestibility, fur condition, blood parameters, fecal scores, and gut microbiota composition. However, our results indicate that different types of diets did not significantly affect the daily weight gain of Ragdoll cats. The CM group showed a significant improvement in the digestibility of dry matter, fat and protein compared to the ED group (p < 0.05) but no improvement in that of fat compared to the RM group. Compared to the ED group, both the CM and RM groups showed significant improvements in fur condition while exhibiting a significant decrease in fecal scores (p < 0.05). The CM and RM groups exhibited enhanced serum antioxidant capacity (p < 0.05) and increased immunity in the cats (p < 0.05). Immunity enhancement in the CM group was significantly higher than that in the RM group(p < 0.05). The ED group showed an increase in the abundance of beneficial bacteria in Ragdoll cat intestines, while the CM and RM groups showed enhancements in the innate microbiota of feline animals. These data, to some extent, suggest that CM is the most suitable diet for Ragdoll cats, but further research on intestine microbiota is still needed. These study findings provide a reference for purebred pet breeding purposes.

Evaluation of Effective Energy Values of Six Protein Ingredients Fed to Beagles and Predictive Energy Equations for Protein Feedstuff

This study evaluated the nutrition composition, the nutrient digestibility, and the energy value of six protein ingredients used in pet food by the difference method in six beagles within a 7 × 6 incomplete Latin square design. The results showed that the apparent total tract digestibility of gross energy (GE) and organic matter (OM) in beagles fed the fish meal (FM) and corn gluten meal (CGM) diets was higher than for those fed the meat and bone meal (MBM), soybean meal (SBM), mealworm meal (MM), and yeast extract (YE) diets (p < 0.05). The digestible energy (DE), metabolizable energy (ME), and net energy (NE) of the MM diet were greater than the other diets, and MBM was the lowest (p < 0.05). The ME of protein ingredients was positively correlated with organic matter and negatively correlated with the ash content. The NE of protein ingredients was positively correlated with the crude protein content and negatively correlated with the ash content. The study resulted in predictive energy equations for protein ingredients that were more accurate than the NRC's predictive equation of ME when the ash content of the ingredient was more than 30% DM. In conclusion, the nutrient digestibility and energy value of corn gluten meal were similar to those of fish meal and those of soybean meal were similar to yeast extract. All predictive energy equations for six protein feedstuffs had slight differences with measured energy values.

Effects of Black Soldier Fly (Hermetia illucens L., BSF) Larvae Addition on In Vitro Fermentation Parameters of Goat Diets

The purpose of this experiment was to evaluate the effects of different levels of BSF on rumen in vitro fermentation gas production, methane (CH4) production, ammonia nitrogen (NH3-N), and volatile fatty acids (VFAs). The experiment comprised four treatments, each with five replicates. The control group contained no BSF (BSF0), and the treatment groups contained 5% (BSF5), 10% (BSF10), and 15% (BSF15) BSF, respectively. Results showed that at 3 h, 9 h, and 24 h, gas production in BSF5 and BSF10 was significantly higher than in BSF0 and BSF15 (p < 0.05). Gas production in BSF5 and BSF10 was higher than in BSF0, while gas production in BSF15 was lower than in BSF0. At 6 h and 12 h, CH4 emission in BSF15 was significantly lower than in the other three groups (p < 0.05). There were no differences in the pH of in vitro fermentation after BSF addition (p > 0.05). At 3 h, NH3-N levels in BSF10 and BSF15 were significantly higher than in BSF0 and BSF5 (p < 0.05). At 6 h, NH3-N levels in BSF5 and BSF10 were significantly higher than in BSF0 and BSF15 (p < 0.05). Acetic acid, propionic acid, butyric acid, and total VFAs in BSF0, BSF5, and BSF10 were significantly higher than in BSF15 (p < 0.05). In conclusion, gas production, CH4 emission, NH3-N, acetic acid, propionic acid, butyric acid, and VFAs were highest in BSF5 and BSF10 and lowest in BSF15.

Protective effect of chicken yolk antibody Y against Campylobacter jejuni induced diarrhea in cats

Campylobacter jejuni (C. jejuni) is a common pathogen that often causes diarrhea, loss of appetite, and even enteritis in domestic cats, affecting their growth and development, especially in kittens under 6 months of age. Oral passive immunization with chicken yolk antibody Y has been proved effective for the treatment of gastrointestinal pathogen infections due to its high specificity. In this study, C. jejuni was isolated from diarrheal cat feces, and the specific egg yolk antibody Y against C. jejuni was demonstrated to effectively inhibit its proliferation in vitro experiments. To evaluate the effect of anti-C. jejuni IgY, the mouse C. jejuni infection model was established and it was found that IgY could alleviate C. jejuni-induced clinical symptoms. Consistent with these results, the reduction of pro-inflammatory factors and intestinal colonization by C. jejuni in the IgY-treated groups, especially in the high dose group. We then evaluated the protective effect of IgY on young Ragdoll cats infected with C. jejuni. This specific antibody reduced the rate of feline diarrhea, protected the growth of young cats, inhibited systemic inflammatory hyperactivation, and increased fecal short-chain fatty acid concentrations. Notably, IgY may have a protective role by changing intestinal amino acid metabolism and affecting C. jejuni chemotaxis. Collectively, specific IgY is a promising therapeutic strategy for C. jejuni-induced cat diarrhea.

Impact of Pediococcus acidilactici GLP06 supplementation on gut microbes and metabolites in adult beagles: a comparative analysis

There is growing interest in the potential health benefits of probiotics for both humans and animals. The study aimed to investigate the effects of feeding the canine-derived probiotic Pediococcus acidilactici GLP06 to adult beagles by analysing the microbiome and metabolome. Twenty-four healthy adult beagles were randomly assigned to four groups. The CK group received a standard diet, while the three probiotic groups, the LG group (2 × 108 CFU/day/dog), MG group (2 × 109 CFU/day/dog), and HG group (2 × 1010 CFU/day/dog), received the standard diet supplemented with varying amounts of probiotics. The results show that, compared to the CK group, total antioxidant capacity was significantly increased in the MG and HG groups (p < 0.05), and superoxide dismutase and catalase were significantly increased in the HG group (p < 0.05). Compared to the CK group, malondialdehyde and blood urea nitrogen content were significantly decreased in the MG and HG groups (p < 0.05). Additionally, secretory immunoglobulin A activity was significantly increased in the HG group compared to the CK and LG groups (p < 0.05), and immunoglobulin G activity was significantly increased in the HG group compared to the CK, LG, and MG groups (p < 0.05). In addition, compared with the CK group, the abundance of Faecalitalea and Collinsella increased in the LG group, and the relative abundance of Tyzzerella and Parasutterella increased in the MG group. The α diversity and the relative abundances of beneficial bacteria (Faecalibacterium, Lachnospiraceae_NK4A1316, and Ruminococcaceae_UCG-005) were higher in the HG group than in the CK group. Furthermore, acetic acid content was significantly increased in the HG group compared to the CK, LG, and MG groups (p < 0.05). Butyric acid, isobutyric acid, and the total SCFA content were significantly increased in the HG group compared to the CK group (p < 0.05). Moreover, metabolome analysis revealed 111 upregulated and 171 downregulated metabolites in the HG group. In conclusion, this study presents evidence that supplementing with P. acidilactici GLP06 can have a positive impact on antioxidant activity, immunoproteins, SCFAs, and gut microbiota in adult beagles. These findings highlight the potential of probiotics as a dietary intervention to enhance gut health and overall wellbeing in companion animals.

Effect of feeding black soldier fly larvae meal based diet on canine skin barrier function, organic antioxidant defence and blood biochemistry

Black soldier fly meal in pet diets is gaining acceptance. This study aimed to assess the use of black soldier fly larvae defatted meal (BSFL) and its impact on blood parameters, biochemical markers, organic antioxidant capacity, skin barrier function and skin and coat quality. A cross-over study involved eight beagle dogs with two periods of 50 days each and a washout period of seven days in between. Two approximately iso-nutritive extruded diets were evaluated, the first containing 29.5% BSFL meal and a control diet containing 26% poultry by-product meal (PBP) as protein source. Skin and coat evaluations and blood collections were conducted before and after each period. Skin barrier function was assessed by measurement of trans epidermal water loss (TEWL) and stratum corneum hydration (SCH) in belly and pinna of the dogs on days 0, 15, 30, and 45 of each period. A trend for higher antioxidant effect significant reduction in serum scavenging capacity was found with PBP for BSFL diet trough malondialdehyde and Vitamin E measurement in dog's serum 2,2-diphenyl-1-picryl-hydrazyl (DPPH) assay. When fed PBP diet dogs exhibited reduction in serum cholesterol triglycerides and decreased LDL levels after 50 days, while dogs fed BSFL presented significant reduction in ALT. TEWL was significantly reduced in belly and pinna over time when dogs were fed BSFL, and TEWL in belly was significantly lower in dogs fed BSFL in comparison to PBP. while Increased SCH was also higher for the BSFL group observed in the same along the feeding period in comparison to PBP, indicating improved ability of the dogs to retain water and keep skin moisture. Improvement skin barrier function could be related to fatty acids from BSFL and increased sebaceous lipids in skin. These are responsible for to avoid water loss and improve skin protection against microbial insults. Inclusion of BSFL as protein source did not promote negative changes in blood biochemistry and had minor antioxidant effect in healthy dogs. However, it proved effective in improving skin barrier function, making BSFL a valuable alternative protein source for dogs, particularly those with sensitive skin or allergies manifesting on the skin.

Influence of a Mixture of Protein Hydrolysate from Black Soldier Fly Larvae and Schizochytrium on Palatability, Plasma Biochemistry, and Antioxidative and Anti-Inflammatory Capacity in Cat Diets

The objective of this research was to evaluate palatability, plasma biochemistry, antioxidative and anti-inflammatory capacity, and immune levels in cats by feeding supplementing inclusion of different levels of a mixture of protein hydrolysate from black soldier fly larvae and schizochytrium (BSFPs) in diets. In the feed experiment, a total of 24 adult cats (12 females and 12 males; BW: 3.02 ± 0.06 kg) were randomly divided into four groups: (1) diet with chicken and fish meal as primary protein resource (CON); (2) diet with 5% BSFPs replacing chicken meal, fish meal, chicken oil, and fish oil (5% BSFPs); (3) 10% BSFPs; and (4) 15% BSFPs. The body weight and feed intake were recorded, and a blood sample was collected for analysis. In the palatability experiment, three diets containing 5%, 10%, and 15% BSFPs were evaluated by comparing with CON. These results suggested that different levels of BSFPs could improve palatability in cat diets by enhancing the first sniff, the first bite, and feed intake (p < 0.05). However, no significant influence existed in body weight and average daily feed intake (p > 0.05). In comparison to the CON group, 5% and 15% BSFPs significantly increased the total protein content, and all treatment groups decreased the triglyceride content and enhanced the calcium concentration in plasma; in addition, the activity of aspartate aminotransferase and alanine aminotransferase and the content of creatinine and urea nitrogen were significantly reduced by the supplementation inclusion of BSFPs in the diets (p < 0.05). The enzyme activity of glutathione peroxidase was dramatically enhanced by the supplementation of 10% and 15% BSFPs in diets compared with the CON diet, and the activity of superoxide dismutase was increased and the malondialdehyde concentration was remarkably reduced in all three treatments (p < 0.05). Compared with the CON group, different levels of BSFPs in the diets significantly increased the immunoglobulin A content in plasma; similarly, the immunoglobulin G concentration was significantly enhanced by the supplementation of 10% and 15% BSFPs in the diets (p < 0.05). Furthermore, the interleukin-1β content was significantly reduced in the inclusion of 10% and 15% BSFPs in the diets, and 15% BSFPs remarkably decreased the content of interleukin-8 in plasma compared with the CON diet (p < 0.05). To sum up, the supplementation of different levels of BSFPs exhibited a positive effect on palatability and enhanced the antioxidant, anti-inflammatory, and immune capacity. Particularly, the addition levels of 10% and 15% BSFPs were more effective in antioxidation, anti-inflammation, and immunity.

Flight toward Sustainability in Poultry Nutrition with Black Soldier Fly Larvae

Black soldier fly larvae (BSFL), Hermetia illucens (L.) (Diptera: Stratiomyidae), have emerged as a promising feed ingredient in broiler chicken diets, known for their high protein content, nutritional richness, and environmental sustainability. This review examines the effects of integrating BSFL into broiler feeds, focusing on aspects such as growth performance, nutrient digestibility, physiological responses, and immune health. The ability of BSFL to transform waste into valuable biomass rich in proteins and lipids underscores their efficiency and ecological benefits. Protein levels in BSFL can range from 32% to 53%, varying with growth stage and diet, offering a robust source of amino acids essential for muscle development and growth in broilers. While the chitin in BSFL poses questions regarding digestibility, the overall impact on nutrient utilization is generally favorable. The inclusion of BSFL in diets has been shown to enhance growth rates, feed efficiency, and carcass quality in broilers, with the larvae's balanced amino acid profile being particularly advantageous for muscle development. BSFL may also support gut health and immunity in broilers due to its bioactive components, potentially influencing the gut's microbial composition and enhancing nutrient absorption and overall health. Moreover, the capacity of BSFL to efficiently convert organic waste into protein highlights their role as an environmentally sustainable protein source for broiler nutrition. Nonetheless, further research is necessary to fully understand the long-term effects of BSFL, ideal inclusion rates, and the impact of varying larval diets and rearing conditions. It is crucial for poultry producers to consult nutritionists and comply with local regulations when incorporating new feed ingredients like BSFL into poultry diets.

Effect of Hermetia illucens Fat, Compared with That of Soybean Oil and Palm Oil, on Hepatic Lipid Metabolism and Plasma Metabolome in Healthy Rats

Palm oil (PO) is currently the most widely used fat source for food production, but insect fat from Hermetia illucens larvae (HF) might be a suitable alternative fat source, because its production is less harmful to the environment. The present study investigated the effect of HF, as compared to PO and soybean oil (SO), on the hepatic lipid metabolism and the plasma metabolome of healthy rats, which were randomly assigned to three groups (n = 10 rats/group), and fed three different semi-synthetic diets containing either SO, PO, or HF as the main fat source for 4 weeks. Feed intake, body weight gain, liver and plasma lipid concentrations, and the hepatic mRNA levels of genes involved in lipid metabolism and inflammation did not differ between groups. Targeted plasma metabolomics revealed 294 out of 630 metabolites analyzed to be different between groups. Principal component analysis showed a clear separation of the plasma metabolomes of the SO group and the other two groups, but no separation of those of the PO and the HF groups. The present study shows that HF exerts no adverse metabolic effects in healthy rats, compared to PO or SO, indicating that HF is a safe alternative fat source to PO for food production.