Aman Paul

Feline food palatability is fundamental to ensure nutritional intake and the commercial success of pet foods, yet the field has several gaps, unresolved contradictions, and methodological inconsistencies. A literature search identified 141 relevant publications. Critical evaluation of this body of work revealed four recurring areas of tension: the inconsistent definition of palatability, where the same term evaluates different constructs; contradictory behavioral indicators, where the same behaviors (e.g., nose-licking) are variably interpreted as positive or negative across studies; methodological fragmentation arising from overarching test selection, study design implementation, and inconsistent or selective reporting; and the disconnect between owners’ perception of palatability and objectively measured feline responses. This critical narrative review discusses the origins of these inconsistencies, their implications for cross-study comparison, and their combined effect on the reliability of existing evidence. Resolving these contradictions may benefit from a proposed integrative framework for defining palatability, a standardized ethogram for behavioral indicators, and a decision framework for selecting assessment methodologies. These approaches could improve the comparability and reliability of future studies, but their effectiveness requires validation.

We aimed to evaluate the effects of including black soldier fly larvae meal (BSFL) meal in a dry extruded food on nutritional quality and some health aspects in healthy adult cats. Two dry extruded foods with either poultry meal (control) or 37.5% BSFL meal were fed to eight (3.8-5.2 kg BW; 2.3-y.o.) cats in a cross-over design with two 28-day periods. Food acceptance was recorded throughout the study and samples were collected during the last 7 days of each period for assessment of apparent total tract nutrient digestibility, faecal consistency, fermentation products and microbiota, and blood biochemistry and haematology. Foods were well-accepted and faeces were well-formed with optimal consistency scores. Digestibility values for dry matter, organic matter, nitrogen and gross energy were considered high for the BSFL meal-based food but lower than for the control food (). Unexpectedly, inclusion of BSFL meal had a profound impact on the intestinal microbial activity and composition as illustrated by increased faecal short-chain fatty acids () and biogenic amines concentrations () and reduced bacterial diversity () and shifts in multiple genera (e.g. more Bifidobacterium) in the faeces (). Minor changes in haematology and serum biochemistry parameters were found and deemed not clinically relevant. Overall, this study showed that a BSFL meal-based extruded dry food is readily accepted by healthy adult cats, yields optimal faecal consistency, had suitable nutrient digestibilities and can support their health when fed for 28 days with new leads for impact on feline gut health.

A digestibility study with laying hens was carried out to determine the nutritional value of a commercial and representative (batch to batch variance adjusted) insect meal based on Hermetia illucens (HI) larvae, (from black soldier fly) which was the objective in this study. A basal diet (BD; CP 15%), formulated and fed as such and an experimental diet (HD; CP 21%) consisting of BD with inclusion of 18% of the HI meal were used in the study. The BD and HD were fed to eight and six replicate metabolic cages, respectively, with eight Dekalb White laying hens each from 25 to 27 weeks of age. Diets (pelleted with TiO₂ as marker) and water were available for ad libitum intake. Excreta was collected during the last three days to determine AMEn and apparent total tract faecal nutrient digestibility coefficients (ATTDC). Distal ileal content was collected at the last day of the experiment to determine apparent ileal amino acids digestibility of diets and HI meal. Using table values for endogenous losses standardised ileal amino acids digestibility coefficient (SIDC) of HI meal were also calculated. Analysed nutrients (g/kg) in HI meal were: 47 moisture, 529 crude protein, 71 ash, 135 fat and thus 218 was calculated as carbohydrates. Determined AME AMEn for HI meal was 3,846 kcal/kg dry matter (DM) and AMEn was 3,498 3,671 kcal/kg DM and ATTDC AFD for crude protein, crude fat and carbohydrates was 0.830, 0.940 and 0.680, respectively. Average SID coefficient for the 18 amino acids was 0.861 86.1%. Among indispensable amino acids SIDC ranged from 0.790% for threonine to 0.950% for phenylalanine and was 0.840% for lysine. These findings highlight that HI meal is an interesting alternative protein source for soybean meal (SBM). Besides market prices and availability, demands for more sustainable poultry production will determine the use of HI meals as alternative for SBM in poultry diets in the near future, especially in regions where SBM is imported from overseas.

Insects are recently gaining popularity as food and feed ingredients in Western countries. This chapter is written with the objective to provide an impression of applicable European (and to some extent North American) legislation to people involved in the insect business. It provides information regarding legislative frameworks concerning the following aspects: (1) insect production including feed for insects, rearing, processing, and animal welfare; (2) applications of insect products including whole insects, proteins, fats, chitin derivatives and frass. Moreover, this chapter also provides recent information about regulatory developments expected in the near future and some challenges that need attention from regulators. Finally, it shows that transparency in the national and international legislative framework will be critical for the future of insect farming and use of insect products in feed, food, and technical applications.

Hermetia illucens meal is one of the most promising alternatives to fishmeal and soymeal. Fat oxidation quality of these products is crucial, as it directly influences the palatability of feed, and health of animals consuming it. During this study, oxidative quality of commercialH. illucens meal, fishmeal and soymeal was evaluated by measuring fatty acid profile, free fatty acid content, peroxide value,p-anisidine value and electron spin resonance spectra of lipid free radicals. Fishmeal and soymeal used in this study had antioxidants, either added (in fishmeal), or naturally present (in soymeal), whereasH. illucens meal had no added antioxidants. Results indicate that fishmeal contain high levels of lipid free radicals and secondary oxidation products, which may adversely affect the health of the animal consuming it. In contrast,H. illucens meal and soymeal are stable in terms of oxidative quality. The majority of soymeal consumed in Europe originates from South America, where soy farming is linked to several social and environmental challenges.H. illucens meal could be a local and sustainable alternative to fishmeal and soymeal. Oxidative stability ofH. illucens meal could be attributed to the short supply chain and careful design of the thermal processing step. In case ofH. illucens meal, thermal processing is effective enough to deactivate sn-1,3-lipase, while causing minimal damage to unsaturated triglycerides.H. illucens meal contain high levels of saturated fats and is thermally processed at mild conditions in comparison to fishmeal and soymeal. This may offer advantage toH. illucens meal in terms of fat oxidation quality.

Black soldier fly larvae (BSFL)-derived proteins are gaining popularity as sustainable pet food ingredients. According to the literature, these ingredients have strong antioxidant and antimicrobial activities. Due to the ability of BSFL protein derivatives to donate hydrogen atoms and/or electrons to counterpoise unstable molecules, they could possibly help in the prevention of osteoarthritis. During this study, the antiarthritic potential of BSFL protein derivatives was evaluated using the following assays: (1) proteinase inhibition, (2) erythrocyte membrane stability, (3) reactive oxygen species (ROS) production by activated macrophages, (4) ROS production by monocytes, and (5) cellular toxicity. Additionally, the glucosamine content of these ingredients was also evaluated. Chicken meal is commonly used in pet food formulations and was used as an industrial benchmark. The results obtained during this study demonstrated the strong antiarthritic potential of BSFL protein derivatives. We found that BSFL protein derivatives are not only useful in preventing the development of arthritis but could also help to cure it due to the presence of glucosamine. We also found that chicken meal could contribute to the development of arthritis by increasing ROS production by monocytes.

Marine feed ingredients derived from cephalopods (e.g., squid) and crustaceans (e.g., krill) are commercially used to improve the palatability of shrimp diets. Increase in global demand for shrimps has resulted in overfishing of these marine organisms and is a matter of concern. Insect protein hydrolysate could be a sustainable alternative for the possible replacement of these marine feed ingredients. During this study, four formulations: diet A (control: not containing any palatability enhancer), diet B (containing squid meal and krill oil), diet C (containing 1% insect protein hydrolysate), and diet D (containing 2% insect protein hydrolysate) were tested for (1) time required by first subject to begin feeding (time to strike) and (2) palatability in Litopenaeus vannamei. Additionally, the chemical composition of all four diet formulations was also analyzed. Results indicate that all diets had similar crude composition. The major essential amino acids in all diets were leucine and lysine, whereas eicosapentaenoic acid was the major omega-3 fatty acid in all diets. There were no significant differences between the mean time to strike for all the tested formulations. Palatability of tested formulations was found in the following order: diet D > diet C > diet B = diet A (p < 0.05), indicating that addition of squid meal and krill oil has no effect on palatability in comparison to control, whereas inclusion of insect protein hydrolysates significantly improves the palatability of formulations. Palatability enhancement potential of insect protein hydrolysate could be attributed to the high free amino acid content and water solubility in comparison to squid meal.

Chitin, and especially its deacetylated variant chitosan, has many applications, e.g. as carrier material for pharmaceutical drugs or as a flocculant in wastewater treatment. Despite its versatility and accessibility, chitin, the second most abundant polysaccharide on Earth, has so far been commercially extracted only from crustaceans and to a minor extent from fungi. Insects are a viable alternative source of chitin, but they have not been exploited in the past due to limited availability. Today however, for the sustainable production of animal feed, insect farming is being developed substantially. The availability of large quantities of insect biomass and chitin‐rich side products such as exuviae and exoskeletons has been increasing. This review provides an overview of recently published studies of chitin extraction from insects, its subsequent conversion into chitosan and the primary analytical methods used to characterize insect‐based chitin and chitosan. We have discovered a large number of research articles published over the past 20 years, confirming the increased attention being received by chitin and chitosan production from insects. Despite numerous publications, we identified several knowledge gaps, such as a lack of data concerning chitin purification degree and chitosan yield. Furthermore, analytical methods used to obtain physicochemical characteristics, structural information and chemical composition meet basic qualitative requirements but do not satisfy the need for a more quantitative evaluation. Despite the current shortcomings that need to be overcome, this review presents encouraging data on the use of insects as an alternative source of chitin and chitosan in the future. © 2020 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI).