Comparative evaluation of the quality and fatty acid profile of meat from brown hares and domestic rabbits offered the same diet

Investigating the Nutritional and Functional Properties of Protaetia brevitarsis Larvae and Isolated Soy Protein Mixtures as Alternative Protein Sources

The growing demand for sustainable and alternative protein sources has spurred interest in insect-based and plant-based proteins. Protaetia brevitarsis (PB) larvae and isolated soy protein (ISP) are notable in this regard, offering potential health benefits and nutritional enhancements. We assessed the feasibility of PB larvae and ISP mixtures as alternative food ingredients. Methods included the optimized purification and freeze-drying of PB larvae, extraction and refinement of legume proteins, physicochemical and antioxidant capacity evaluations, DPPH radical scavenging activity measurement, total phenolic and flavonoids content quantification, general component analysis, amino acid profiling using HPLC, fatty acid profiling through gas chromatography, and mineral content analysis using inductively coupled plasma spectrometry. The study found that certain PB:ISP ratios, particularly a 7:3 ratio, significantly improved the blend's antioxidant capacity, as evidenced by DPPH scavenging activity. This ratio also impacted the nutritional profile by altering the mixture's general components, with a notable increase in moisture, crude protein, and fiber and a decrease in crude fat and ash. Amino acid analysis revealed a balanced presence of essential and non-essential amino acids. The fatty acid profile was rich in unsaturated fatty acids, especially in certain ratios. Mineral analysis showed a complex interplay between PB larvae and ISP, with some minerals decreasing and others increasing in the blend. PB larvae and ISP mixtures have significant potential as alternative protein sources, offering a diversified nutritional profile and enhanced antioxidant properties. The 7:3 ratio of PB larvae to ISP has been shown to be particularly effective, suggesting that this ratio may offer an optimal balance for enhancing the overall nutritional quality of the mixture. This study sets the stage for future research to further explore and optimize the potential of these mixtures for human consumption while considering the challenges of consumer acceptance and long-term safety.

Potential and limitations of rabbit meat in maintaining food security in Ukraine

The aim of the present review was to assess whether rabbit meat production can help to improve food security in Ukraine and whether it can make a meaningful contribution to the national economy. Rabbit meat is a nutrient-rich and affordable food with a lower environmental impact than red meat from cattle or sheep. Rabbit meat is considered healthy, as it is lower in fat, cholesterol and sodium than other types of meat, and rich in protein. In addition, rabbit meat proteins can serve as a source of bioactive peptides with the angiotensin converting enzyme (ACE) inhibition properties. The health-promoting properties of rabbit meat and role of associated by-products in providing nutritious and safe food for consumers, and in reducing waste in the meat sector, should be promoted. In Ukraine, rabbit meat products are already recommended as part of a healthy diet for children, pregnant women and the elderly, and the market could be broadened by introducing more rabbit-based products for the whole population. Rabbit production in Ukraine is a promising area of economic activity and with a broader market this segment could increase further and become a significant part of the economy. However, the rabbit farming sector in Ukraine needs comprehensive improvement to address existing issues, including the introduction of sustainable production methods in accordance with European animal welfare and meat quality standards.

Effects of Sex and Hunting Season on Carcass and Meat Quality Characteristics of the Brown Hare (Lepus europaeus)

The objective of the study was to determine the effects of sex and hunting season on the carcass, meat and fat quality of hunted brown hares (Lepus europaeus). Twenty-two hares of both sexes hunted in winter (December) during two hunting seasons in accordance with the law on hunting in Lithuania were evaluated using reference methods The data were subjected to two-factor analysis of variance in the general linear (GLM) procedure. No significant differences in carcass measurements and muscularity or internal organs between the sexes of brown hares were found; however, the hunting season appeared to affect the size of hares. The biceps femoris (BF) thigh muscle of males had lower (p < 0.05) dry matter content and higher (p < 0.05) drip loss compared with females. The hunting season demonstrated an effect (p < 0.001) on protein and hydroxyproline contents in the longissimus thoracis et lumborum (LTL) and affected dry matter, protein and hydroxyproline contents (p < 0.05, p < 0.001 and p < 0.01, respectively) in BF muscles, and differences in the colour of muscles were also observed. The shear force in the Warner-Bratzler (WB) test was higher (p < 0.001 and p < 0.01, respectively) for LTL and BF muscles during the first hunting season. The hunting season did not affect the total SFA in the intramuscular fat (IMF) of all the tissues, but it affected levels of monounsaturated (MUFA) and polyunsaturated (PUFA) fatty acids in the muscles. No differences were found in the total saturated fatty acids (SFA) of both muscles between the sexes, but females demonstrated lower (p < 0.05 and p < 0.01, respectively) and more favourable n-6/n-3 PUFA ratios in the muscles and fat and a lower (p < 0.05) thrombogenic (TI) index in the LTL compared with males.

Effects of edible chitosan coating containing Salvia rosmarinus essential oil on quality characteristics and shelf life extension of rabbit meat during chilled storage

Rabbit meat is one of the most consumed meats throughout the world and is extremely susceptible to spoilage due to its high protein and moisture content. Natural preservatives with antioxidant and antibacterial properties are needed to maintain meat quality and increase its shelf life. This study examined the effect of 1% chitosan (CH), 0.2% rosemary (Salvia rosmarinus) essential oil (REO), and their combination on pH, total volatile basic nitrogen (TVB-N) and thiobarbituric acid (TBA) levels, and the microbial profile of rabbit meat stored over 12 days at 4 °C. During this time, changes in appearance, odor, and texture were also noted. The shelf lives of samples treated with only 1% CH coating, or in combination with 0.2% REO, were longer than those of untreated samples. These results showed that samples treated with both CH and REO were still acceptable until the 12th day and resulted in significantly lower meat demerit scores in these treated groups compared with untreated meat. In all groups, the pH, TVB-N, and TBA values increased over time, but these values were significantly higher (p < 0.05) in untreated samples. Microbial analysis results showed that chilled rabbit meat samples treated with combined 1% CH and 0.2% REO reduced Enterobacteriaceae, Pseudomonas, and Psychrotrophic counts. The experimental results demonstrated that using CH coating in combination with REO improved the quality of rabbit meat and could be an effective approach to reduce rabbit meat deterioration during chilled storage.

Proximate Chemical Composition, Amino Acids Profile and Minerals Content of Meat Depending on Carcass Part, Sire Genotype and Sex of Meat Rabbits

Simple Summary

Rabbit meat is popular with consumers mainly for its high-quality protein. Among the main factors influencing the characteristics of rabbit meat proteins to appertain the breed, genotype, carcass part and age. Conventional production of rabbit meat in many European countries is mainly ensured by intensive production systems, when commercial meat-type albinotic rabbit crossbreds are used. However, spotted and solidly coloured lines of meat rabbit breeds have begun to be used in rabbit breeding schemes as some consumers have begun to negatively perceive meat from albinotic coloured rabbits. The aim of the present study was to assess the effects of the sire genotype, sex and carcass part on the composition of meats of rabbits fattened under conditions where no synthetic drugs were used. Crossbreeding of Mecklenburger Schecke sires with a commercial dam line of HYLA rabbits resulted in a worse nutritional quality of meat proteins in progeny. These findings point to a possible risk of alterations in the nutritional quality of meat proteins when using different rabbit sire genotypes than those originally intended for the specific commercial crossbreeding scheme.

Abstract

The aim of the study was to assess the effects of the sire genotype, sex and carcass part on the composition of the meat of rabbits, which were fattened under conditions where no synthetic drugs were used. As for carcass parts, the higher content of both total amino acids (AA) and all essential AA (EAA) monitored was found in the Longissimus thoracis et lumborum (LTL) muscle as compared to hind leg meat (p ˂ 0.001). Significant effects of the rabbit sire genotype and the genotype x sex interaction on proportions of some AA in meat were found (p ˂ 0.001). Crossbreeding of the Mecklenburger Schecke (MS) sires with a commercial dam line of HYLA rabbits resulted in a lower proportion of the total AA and all EAA monitored in meats of MS sired males as compared to MS sired females and HYLA rabbits (p ˂ 0.05). The sex-related effect on AA profile was not so noticeable in final commercial crossbreds of HYLA rabbits when compared to MS sired progeny. These findings point to a possible risk of alterations in the nutritional quality of meat proteins when using different rabbit sire genotypes than those originally intended for the specific commercial crossbreeding scheme. However, on the contrary, higher contents of magnesium (p ˂ 0.05), manganese (p ˂ 0.001) and zinc (p ˂ 0.05) were found in meats of MS sired progeny as compared to HYLA rabbits.

Effect of Dietary Grape Pomace on Fattening Rabbit Performance, Fatty Acid Composition, and Shelf Life of Meat

The use of agroindustry by-products in animal diets allows the use of residues that are not fit for human consumption. In this study, it was investigated whether fattening commercial rabbits during 30 days with a non-medicated feed, with 20% addition of grape pomace (GPD), affected production traits and the fatty acid composition, antioxidants properties, and the shelf life of the meat compared to a conventional strategy (CON). Furthermore, it was tested, by chromatographic analysis, whether this alternative diet allowed the transfer of phenolic compounds to the meat. Thirty-six weaned rabbits were allotted to the two treatments. In each treatment, 18 rabbits were fattened in three indoor cages, each housing three males and three female rabbits. No significant differences were found in live weights (p > 0.05), but the feed conversion rate and carcass weight and yield were found to be impaired in the GPD group (p ≤ 0.05). The GPD group had a higher intramuscular fat percentage (2.01 vs. 1.54), improved polyunsaturated/saturated fatty acids ratio (0.75 vs. 0.66), and better atherogenicity (0.71 vs. 0.83) and thrombogenicity (1.14 vs. 1.24) indexes, while the n-6/n-3 ratio was higher (25.4 vs. 20.3). Total volatile basic nitrogen in meat was lower in the GPD group (p = 0.01), suggesting a delayed spoilage. However, no improvements in total phenolic content, antioxidant capacity, reducing power, and lipid oxidation (p > 0.05) were found in the meat. Even though the GPD pellets offered to the animals had several grape-derived phenolic compounds, and higher antioxidant properties compared to the CON diet, none of the phenolic compounds detected in feeds were detected in the meat samples.

Putting the Spring back into the Hare (Pedetes capensis): Meat Chemical Composition of an Underutilized Protein Source

Alternative protein sources are gaining increasing global attention as a solution to address future protein demands. Determining the chemical composition of meat alternatives is vital to confirm that it is nutritious, but also to increase product value and promote its utilization. The carcass characteristics and chemical composition of springhare, an underutilized protein source, was found to be comparable to that of commercially reared rabbits. Hence, its introduction into the commercial supply chain would likely not offset consumers accustomed to purchasing rabbit/hare meat. Springhare meat had a high protein content (~22.5 g/100 g meat) and low lipid (<1.3 g/100 g meat) content. The meat's fatty acids mainly comprised C18:2n6c (γ-linoleic acid; 24%), C18:0 (stearic acid; 20%), C16:0 (palmitic acid; 19%), C20:4n6 (arachidonic acid; 15%) and C18:1n9c (oleic acid; 13%). Although sex did not significantly influence the carcass characteristics and meat composition, season did have an effect (p < 0.05) on the fatty acid profile. The meat harvested in summer had higher (p < 0.05) concentrations of favorable unsaturated fatty acids, C18:2n6c, C18:3n6, C18:3n3 (α-linolenic acid), C20:2n6 (eicosadienoic acid), C20:3n3 (eicosatrienoic acid), compared to the meat obtained in winter, which contained more (p < 0.05) saturated fatty acids. The results verify that springhare can be utilized as a viable alternative protein source.

Contribution of Short Chain Fatty Acids to the Growth of Pseudomonas aeruginosa in Rhinosinusitis

Background: Chronic rhinosinusitis (CRS) is characterized by complex bacterial infections with persistent inflammation. Based on our rabbit model of sinusitis, blockage of sinus ostia generated a shift in microbiota to a predominance of mucin degrading microbes (MDM) with acute inflammation at 2 weeks. This was followed by conversion to chronic sinus inflammation at 3 months with a robust increase in pathogenic bacteria (e.g., Pseudomonas). MDMs are known to produce acid metabolites [short chain fatty acids (SCFA)] that have the potential to stimulate pathogen growth by offering a carbon source to non-fermenting sinus pathogens (e.g., Pseudomonas). The objective of this study is to evaluate the concentrations of SCFA within the mucus and its contribution to the growth of P. aeruginosa. Methods: Healthy and sinusitis mucus from the rabbit model were collected and co-cultured with the PAO1 strain of P. aeruginosa for 72 h and colony forming units (CFUs) were determined with the targeted quantification of three SCFAs (acetate, propionate, butyrate). Quantification of SCFAs in healthy and sinusitis mucus from patients with P. aeruginosa was also performed via high performance liquid chromatography. Results: To provide evidence of fermentative activity, SCFAs were quantified within the mucus samples from rabbits with and without sinusitis. Acetate concentrations were significantly greater in sinusitis mucus compared to controls (4.13 ± 0.53 vs. 1.94 ± 0.44 mM, p < 0.01). After 72 h of co-culturing mucus samples with PAO1 in the presence of mucin medium, the blue-green pigment characteristic of Pseudomonas was observed throughout tubes containing sinusitis mucus. CFUs were higher in cultures containing mucus samples from sinusitis (8.4 × 10⁹ ± 4.8 × 10⁷) compared to control (1.4 × 10⁹ ± 2.0 × 10⁷) or no mucus (1.5 × 10⁹ ± 2.1 × 10⁷) (p < 0.0001). To provide evidence of fermentative activity in human CRS with P. aeruginosa, the presence of SCFAs in human mucus was analyzed and all SCFAs were significantly higher in CRS with P. aeruginosa compared to controls (p < 0.05). Conclusion: Given that SCFAs are solely derived from bacterial fermentation, our evidence suggests a critical role for mucin-degrading bacteria in generating carbon-source nutrients for pathogens. MDM may contribute to the development of recalcitrant CRS by degrading mucins, thus providing nutrients for potential pathogens like P. aeruginosa.

Effect of Solid-State Fermented Wheat Bran Supplemented with Agrimony Extract on Growth Performance, Fatty Acid Profile, and Meat Quality of Broiler Chickens

Simple Summary

The current work evaluates the application of solid-state fermented wheat bran supplemented with agrimony extract in broiler nutrition. Broiler production parameters, blood and bone variables and meat quality were analysed. The quality of breast and thigh meat was evaluated by the use of physicochemical variables, fatty acid profile, lipid oxidation and sensory variables. The presented results showed that supplementation of the broiler diet with fermented feed positively influenced the quality of the produced breast and thigh meat. The application of fermented feed increased the nutritional value of broiler chicken meat, as shown via the positive modification of the fatty acid profile, without affecting sensory quality.

Abstract

The impact of the broiler diet modification on the following parameters was evaluated: meat quality, carcass traits, and bone and blood parameters. One hundred twenty one-day-old COBB 500 broiler chickens were assigned to three experimental groups (40 birds per group) with four replications (10 per pen) for 35 days of fattening. The control (C) was fed a basic feed mixture. The diet supplemented with 10% of fermented feed (FF10) and additionally supported by 0.2% of agrimony extract (FF10 + AE) was applied to the second and third groups, respectively. FF10 showed both a lower average daily feed intake and total feed consumption when compared to that of C (p < 0.05). Lower concentration of alkaline-phosphatase and calcium and higher total lipids and triglycerides in blood were observed in FF10 + AE. Breast and thigh meat showed a lower content of polyunsaturated fatty acid n-3 and n-6 in the FF10 + AE group (p < 0.01). The increase of gamma-linolenic acid content in breast and thigh meat samples obtained from the experimental groups was significant (p < 0.001 and p < 0.05; respectively). Lower lipid oxidation was observed in the thigh muscle of the FF10 + AE group on the first day of storage (p < 0.01). The current study indicates that FF10 + AE supplementation can be successfully applied to enhance broiler performance and meat quality.