Mineral Composition of Cereal and Cereal-Free Dry Dog Foods versus Nutritional Guidelines

Proximate analysis and profiles of amino acids, fatty acids, and minerals in insect-based foods for dogs

OBJECTIVE

To analyze crude protein, crude fat, crude ash, crude fiber, amino acids, fatty acids, and minerals in insect-based dog foods and to evaluate their compliance with nutritional guidelines.

METHODS

Proximate analysis, mineral analysis, amino acid profiling, and fatty acid composition analysis were conducted from November 27, 2023, through February 2024 on 18 commercially available insect-based dog foods formulated for all-life-stage or adult dogs.

RESULTS

Proximate analysis results revealed that all 18 pet foods met the Association of American Feed Control Officials guidelines. However, discrepancies were observed between the values listed on the packaging and those measured in 7 foods. Mineral analysis showed that while all foods met the Association of American Feed Control Officials guidelines for magnesium, discrepancies were found in calcium, phosphorus, zinc, iron, and copper content, with several samples failing to meet recommended levels. Additionally, 2 foods exceeded the recommended maximum ratio for certain fatty acids. Black soldier fly larvae-based foods contained higher levels of lauric and myristic acids compared to other insect-based foods.

CONCLUSIONS

Insect-based dog foods show promise as sustainable protein sources, but discrepancies in mineral content and fatty acid ratios highlight the need for both stricter regulation and better enforcement of existing guidelines to ensure nutritional adequacy for dog health and accurate labeling.

CLINICAL RELEVANCE

This study provides valuable insights into the nutritional composition of insect-based dog foods, revealing inconsistencies in mineral content and fatty acid ratios. These findings can help the pet food industry develop more nutritionally consistent insect-based diets.

Analysis of chicken and pig DNA content in commercial dry foods for adult cats

Among pets, cats are the most popular in Europe. Despite the fact, the interest in the safety and quality of their food is much lower compared to the interest of caregivers in the nutrition of dogs. In this research, 27 commercial cat foods were analyzed for mislabeled component composition. Cat foods were divided into a control group, a group of fish foods and a group of other foods with alternative sources of animal protein. Chicken and pig DNA detection was performed using real-time PCR. In this research, 100% of the cat foods contained chicken DNA and 96% of the foods - pig DNA, despite the lack of declaration of these ingredients on the product label. The results indicate that cat food appear to be mislabeled to an even greater extent than dog food. Moreover, manufacturers' declarations in terms of ingredient composition do not reflect the actual composition of commercial products available on the market and intended for everyday feeding of animals. Mislabeling of these products also poses a risk for animals suffering from food allergies.

Comparative Analysis of Spray-Dried Porcine Plasma and Hydrolyzed Porcine Protein as Animal-Blood-Derived Protein Ingredients for Pet Nutrition

Spray-dried porcine plasma (SDPP) and hydrolyzed porcine protein (HPP) are promising animal protein ingredients sourced from healthy animal blood that are rich in biomolecules, including immunoglobulins, and can be an appropriate and valuable animal protein ingredient to supply the growing need for ingredients that meet the natural needs of carnivorous pets. The aim of this preliminary study was to analyze the chemical composition and mineral profile of a novel HPP compared with results for SDPP. The basic composition analysis followed AOAC guidelines, and the elemental analysis utilized atomic absorption spectrometry. Statistical comparisons employed an independent Student's t-test (p < 0.05). Both SDPP and HPP are low in moisture (<4.3%) and rich in protein, with SDPP significantly exceeding HPP (75.4% vs. 71.4%). They boast mineral richness indicated by crude ash content (12.7% and 12.5%), featuring Na, K, P, and the trace elements Mo, Fe, and Zn. Notably, SDPP contains elevated molybdenum levels (51.39 mg/100 g vs. 10.93 mg/100 g in HPP), an essential element for diverse animal functions. Quantifying these elements in raw materials aids in achieving optimal nutrient levels in the final product. The study underscores SDPP as an excellent protein source, confirming that its nutritional value is similar to or better than other protein components in pet food.

Association between anemia and depression: results from NHANES 2005-2018 and mendelian randomization analyses

BACKGROUND

The relationship between anemia and depression remains controversial.

OBJECTIVE

To explore the association between anemia/hemoglobin and depression.

METHODS

The data for our cross-sectional study were obtained from the National Health and Nutrition Examination Survey (NHANES) 2005-2018. Weighted multivariate logistic regression was performed to examine the association between anemia/hemoglobin and depression. Inverse variance weighted (IVW), weighted-median, and MR-Egger were used in MR analyses to assess the causal relationship between anemia/hemoglobin and depression. Heterogeneity and directional pleiotropy were assessed using the Cochrane Q test and Egger-intercept test, respectively. Sensitivity analysis was conducted by the leave-one-out approach. All analyses were carried out using IBM SPSS 24.0 and R version 4.2.2.

RESULTS

A total of 29,391 NHANES participants were included in this study. After adjusting for all covariates, the association between anemia/hemoglobin and depression was not significant (P < 0.05). IVW estimates revealed that broad anemia had no significant effect on the risk of depression (OR = 1.00, 95% CI = 0.99-1.01, P = 0.432). Findings of weighted median and MR-Egger were consistent with those from IVW (weighted median: OR = 1.00, 95% CI = 0.99-1.02; P = 0.547; MR-Egger: OR = 1.01, 95% CI = 0.98-1.03, P = 0.605). The results of three MR Analyses methods also showed no causal association between hemoglobin and depression.

CONCLUSIONS

Our findings do not support a causal association between anemia and depression. The association between hemoglobin concentration and depression was not statistically significant either.

Mineral and heavy metal content in dry dog foods with different main animal components

Dog caregivers, mainly for economic reasons and easy availability, choose dry, over the counter diets (OTC). The mineral composition of OTC foods depends primarily on the components used in the production of the pet food. Regardless of the main component of the food, it must meet the recommended minimum mineral content, established by nutritional guidelines. Therefore, the aim of this study was to determine the mineral (Ca, K, Mg, Na, Fe, Mn, Zn, Cu, Mo) and heavy metal content (Pb, Co, Cd, Cr, Ni) using the methods of colorimetry and mass spectrometry, of OTC dry dog foods and to compare with the FEDIAF and AAFCO nutritional guidelines. Dry foods pose no risk to dogs in terms of heavy metal content. The worst results in terms of mineral content were obtained in mixed foods, therefore it is worth considering feeding the dog a mono-protein food. The PCA analysis disproved our hypothesis and revealed that the main animal source did not statistically significantly affect the levels of minerals and their ratios. However, the analysis of contrasts confirms the differentiation of the content of individual minerals between the groups of foods. For the first time, we proved that pet food with a mineral composition similar to the MIN-RL may be characterized by unfavorable mineral ratios.

Smart sensory polymer for straightforward Zn(II) detection in pet food samples

We report on an innovative method to measure the Zn(II) concentration in commercial pet food samples, both wet and dry food. It is based on a colorimetric sensory polymer prepared from commercial monomers and 0.5 % of a synthetic monomer having a quinoline sensory core (N-(8-(2-azidoacetamido)quinolin-5-yl)methacrylamide). We obtained the sensory polymer as crosslinked films by thermally initiated bulk radical polymerization of the monomers of 100 μm thickness, which we punched into Ø6 mm sensory discs. The immersion of the discs in water solutions containing Zn(II) turned the fluorescence on, allowing for the titration of this cation using the G parameter of a digital picture taken to the discs. The limits of detection and quantification were 29 and 87 µg/L, respectively. Furthermore, we measured the concentration of Zn(II) even in the presence of other cations, detecting no significant interferences. Thus, in a further step, we obtained the concentration of Zn(II) from 15 commercial pet food samples, ranging from 19 to 198 mg/kg, following a simple extraction procedure and contacting the extractant with our sensory discs. These results were contrasted with that obtained by ICP-MS as a reference method.

A comparative study of nutrient composition, bioactive properties and phytochemical characteristics of Stauntonia obovatifoliola flesh and pericarp

A comparative study was conducted among the flesh (SOF) and pericarp (SOP) of Stauntonia obovatifoliola, a wild edible fruit in China. The nutrient composition of both these tissues was firstly quantified, and liquid-liquid extraction was then used to separate their methanolic extracts to get petroleum ether, chloroform, ethyl acetate, n-butanol, and residual aqueous fractions, which were evaluated for their total phenol content (TPC), total flavonoid content (TFC), antioxidant capacities, and α-glucosidase and acetylcholinesterase inhibition abilities. Finally, high-performance liquid chromatography (HPLC) was used to analyze their phytochemical composition. The results revealed the excellent nutritional properties of both SOF and SOP, especially SOP (total dietary fiber, 15.50 g/100 g; total amino acids, 0.80 g/100 g; vitamin C, 18.00 mg/100 g; Ca, 272.00 mg/kg; K, 402.00 mg/100 g). For both tissues, their ethyl acetate fractions showed the highest TPC (355.12 and 390.99 mg GAE/g DE) and TFC (306.58 and 298.48 mg RE/g DE). Surprisingly, the ethyl acetate fraction of SOP exhibited the strongest DPPH and ABTS radical scavenging capacity with 1046.94 and 1298.64 mg Trolox/g, respectively, which were higher than that of controls Vc and BHT. In contrast, their chloroform fractions exhibited the strongest ferric reducing antioxidant power (1903.05 and 1407.11 mg FeSO₄/g DE) and oxygen radical absorbance capacity (951.12 and 1510.21 mg Trolox/g DE). In addition, the ethyl acetate fraction of SOF displayed superior α-glucosidase inhibition ability with the IC₅₀ value of 0.19 mg/mL, which was comparable to control acarbose. In comparison, the ethyl acetate fraction of SOP had the best acetylcholinesterase inhibition ability with the IC₅₀ value of 0.47 mg/mL. The HPLC analysis results demonstrated that the ethyl acetate fraction of SOP showed significantly higher phenolic content, particularly for phenolic acids (p-hydroxybenzoic acid, 8.00 ± 0.65 mg/g) and flavonoids (epicatechin, 28.63 ± 1.26 mg/g), as compared to other samples. The above results suggest that Stauntonia obovatifoliola, especially its pericarp, had excellent nutrient compositions, bioactive properties and phytochemical characteristics, and had the potential to be developed as natural functional food.

Recovery of microelements from municipal sewage sludge by reed canary grass and giant miscanthus

The aim of the study was to evaluate the content, uptake, and utilization of Al, Mn, Fe, Co, and Mo from municipal sewage sludge by the reed canary grass (RCG) and the giant miscanthus (MG). The impact of sewage sludge on the mass ratios between microelements contained in the plant biomass was analyzed as well. The long-term field experiment consisted in application of four levels of fertilization with sewage sludge: 10, 20, 40, and 60 Mg DM·ha^-1. A non-fertilized control object (0 Mg DM·ha^-1) was used as well. The miscanthus biomass was characterized by higher content of Al and Mn, whereas higher levels of Fe, Co, and Mo were determined in the reed canary grass biomass. As in the case of the element content, the giant miscanthus was characterized by highest level of Al and Mn uptake, while the highest uptake of Fe, Co, and Mo was exhibited by the reed canary grass. In the group of the analyzed microelements, the giant miscanthus showed the highest the recovery of Mo (47%) followed by Mn (39%), Fe (35%), and Co (15%), and the lowest uptake was determined in the case of Al (5%).

Insects as Feed for Companion and Exotic Pets: A Current Trend

The objective of this review was to carry out a comprehensive investigation of the benefits of incorporating insects as a pet food ingredient and the implications this can have in determining a market demand for insect-based pet foods. Black soldier fly larvae (Hermetia illucens), mealworm larvae (Tenebrio molitor) and adult house crickets (Acheta domesticus) are currently used in pet food. These insects are widely fed to exotic pets, mainly in whole, live or dehydrated formats. They are also incorporated as meal or fat and are offered to cats and dogs as dry or wet food and treats. Scientific studies about the use of insects for dog and cat feed are scarce. Most studies are in dogs. Research shows that insect nutrients, mainly amino acids, have high digestibility, are beneficial to health, do not have any detrimental effect on the gut microbiota and are accepted by dogs. In several countries, insects are approved for use in pet food and commercialization has spread throughout the world. Pet owners are willing to try foods made with insect meal for their pets. In conclusion, the use of insects in pet food is a reality that is taking on more and more prominence.

Endocranial volume increases across captive generations in the endangered Mexican wolf

Endangered animals in captivity may display reduced brain sizes due to captive conditions and limited genetic diversity. Captive diets, for example, may differ in nutrition and texture, altering cranial musculature and alleviating constraints on cranial shape development. Changes in brain size are associated with biological fitness, which may limit reintroduction success. Little is known about how changes in brain size progress in highly managed carnivoran populations and whether such traits are retained among reintroduced populations. Here, we measured the endocranial volume of preserved Mexican wolf skulls across captive generations and between captive, wild, and reintroduced populations and assessed endocranial volume dependence on inbreeding and cranial musculature. Endocranial volume increased across captive generations. However, we did not detect a difference among captive, wild, and reintroduced groups, perhaps due to the variability across captive generations. We did not find a relationship between endocranial volume and either inbreeding or cranial musculature, although the captive population displayed an increase in the cross-sectional area of the masseter muscle. We hypothesize that the increase in endocranial volume observed across captive generations may be related to the high-quality nutrition provided in captivity.

Diet and dog characteristics affect major and trace elements in hair and blood of healthy dogs

Obtaining correct amounts of essential elements, and avoiding toxic metals are key factors in dog health. Through analyzing major and trace elements in hair and blood of 50 healthy companion dogs using ICP-MS, we study their associations with dog characteristics and diet, hypothesizing that eating the same diet long-term results in strong correlations between hair and blood element concentrations, and that dog characteristics and diet affect element status. The correlation between hair and blood was significant for Hg (R = 0.601, p = 0.000) and Pb (R = 0.384, p = 0.010). The following associations were significant (p < 0.05): Dark hair had higher Ca and Mg compared to light hair. Females had higher hair Zn, blood Mn, and blood As compared to males. Blood Mn and Se increased, while blood Pb decreased with age. Raw diet fed dogs had higher hair Zn and Se compared to dry or mixed diet fed dogs, and lower blood Mn compared to dry diet fed dogs. Dry and mixed diet fed dogs had higher blood Cd compared to raw diet fed dogs. Mixed diet fed dogs had higher hair Ca and Mg compared to raw or dry diet fed dogs, and higher hair Pb compared to dry diet fed dogs. Wild game consumption was associated with higher blood Pb, and rice consumption with higher blood As. In conclusion, hair provides an alternative for assessing Hg and Pb exposure, and major and trace elements status is affected by hair color, sex, age, and diet.

Evaluation of nutritional value and microbiological safety in commercial dog food

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

Nutritional Evaluation and Risk Assessment of the Exposure to Essential and Toxic Elements in Dogs and Cats through the Consumption of Pelleted Dry Food: How Important Is the Quality of the Feed?

Dry feed for pets lacks specific legislation regarding maximum residue limits for inorganic elements. The aim of the present study was to determine the content of 43 inorganic elements in dog and cat feed, studying whether there were differences according to the supposed quality of the food and performing the risk assessment for health. Thirty-one and thirty packages of pelleted dry food for cats and dogs, respectively, were analyzed. After acidic microwave-assisted digestion, elements were detected and quantified by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). In general, we did not observe important differences in the content of elements according to the supposed quality of the brand. Among trace elements, selenium and manganese are above the dietary reference value. Arsenic and mercury showed the highest acute hazard indexes, which make them risk factors for the health of dogs and cats. Aluminum, uranium, antimony and vanadium contents were above the toxic reference value and showed the highest acute hazard indexes. It is necessary to improve the legislation regarding the food safety of pets, for their health and to protect the rights of consumers.