Donkey Meat Research Articles

Composition of Donkey Meat (Equus Asinus) from the Puno Region, Peru

Objective: To determine the proximate chemical composition of donkey meat (Equus asinus) considering the variables of animal class (young and adult) and commercial cut (shoulder, rib and leg) with the purpose of nutritionally assessing it as an alternative source of red meat. Theoretical Framework: Donkey meat is characterized by a low intramuscular fat content and could be used as a valid alternative to other species of red meat such as beef and sheep in the Puno region, Peru. However, little is known about the nutritional quality of meat from donkeys that are slaughtered at the main equine slaughterhouse in southern Peru. Method: Muscle tissue samples were taken from the following muscles: deltoid, Longissimus dorsi and biceps femoris representing the commercial cuts of shoulder, rib and leg, respectively. Chemical analysis (moisture, protein, fat and ash) was performed following the protocols established for meat by the Association of Official Analytical Chemists (AOAC), in the Bromatology Laboratory of the Faculty of Veterinary Medicine and Zootechnics of UNA-Puno. Data analysis was performed in a randomized complete block design (DBCA) and the LSD significance test (α=0.05). Results and Discussion: The proximate chemical composition of donkey meat is as follows: moisture 73.79%, protein 19.23%, fat 4.53% and ash 1.20%. The animal class (young and adult) and the commercial cut (shoulder, rib and leg) have a significant effect on the moisture and fat content (p≤0.05), with an inverse relationship between the two; but there is no effect on the protein and ash content (p>0.05). Implications of the research: It was possible to demonstrate that the meat of donkeys from the Puno region has a similar composition to the red meat of other domestic species, so it can be a good alternative to replace red meat. Originality/Value: This study contributes to the literature by knowing the chemical composition of donkey meat from the Puno region, Peru for consumption purposes as a substitute for red meat or for the preparation of meat by-products.

The Use of Horse and Donkey Meat to Enhance the Quality of the Traditional Meat Product (Kaddid): Analysis of Physico-Chemical Traits.

The aim of this study was to evaluate the use of horse and donkey meat in the production of kaddid-a traditional dish typically not made with these meats-from a physical and chemical perspective. The results showed that both meats exhibit similar water retention during cooking, contributing to comparable tenderness and juiciness, with no significant differences in pH values, indicating similar quality (p > 0.05). However, their amino acid profiles differ: horse meat contains lower levels of glutamate (p < 0.05), methionine (p < 0.01), isoleucine (p < 0.05), and leucine (p < 0.05), but higher levels of proline (p < 0.05), histidine (p < 0.01), and lysine (p < 0.001) compared to donkey meat. Both meats provide essential amino acids. Horse meat is richer in saturated and monounsaturated fatty acids (32.44% and 39.58%, respectively), while donkey meat has a higher content of polyunsaturated fatty acids (31.51%), with a more favorable PUFA/SFA ratio, suggesting better cardiovascular health benefits. In terms of dried meat, donkey kaddid has a higher protein (17.45 g/100 g) and lower fat content (2.1 g/100 g) compared to horse kaddid (16.7 g/100 g, and 3.5 g/100 g, respectively) (p < 0.05). These findings inform consumer choices and production practices, promoting the use of horse and donkey meat for kaddid production.

Transcriptomic analysis of different intramuscular fat contents on the flavor of the longissimus dorsi tissues from Guangling donkey

BackgroundIn this study, researchers aimed to explore the impact of intramuscular fat (IMF) concentration on the flavor of donkey meat, specifically in the longissimus dorsi muscle of Guangling donkeys. The internal volatile organic compounds that cause the flavor differences between donkey muscles are not clear at present. Transcriptomic technologies were utilized to analyze gene expression and its relationship to donkey meat flavor. MethodThirty Guangling donkeys had their IMF content evaluated in the longissimus dorsi muscle. Based on IMF content, 16 donkeys of similar ages were divided into two groups: low-fat (L) and high-fat (H). Headspace solid-phase microextraction Gas chromatography-mass spectrometry (HS-SPME-GC–MS) and headspace solid phase microextraction mass spectrometry were used to identify potential flavor components that differed between the two groups. ResultsFive key volatile substances were identified, and WGCNA and KEGG analysis was conducted to analyze the genes associated with these substances. The results showed that pathways like PPAR signaling, nucleotide excision repair, glucagon signaling, arachidonic acid metabolism, and glycolysis/glycogenesis were involved in lipid deposition. Additionally, a gene-gene interaction network map was constructed, highlighting the importance of hub genes such as EEF2, DDX49, GAP43, SNAP25, NDUFS8, MRPS11, RNASEH2A, POLR2E, POLR2C and ALB in regulating key flavor substances. ConclusionThis study provided valuable insights into the regulation of genes and protein expression related to flavor substances in donkey meat. It also deepened understanding of the influence of IMF on flavor and laid a foundation for future molecular breeding improvements in Guangling donkeys.

Liquid Chromatography-Mass Spectrometry-Based Metabolomics Reveals Dynamic Metabolite Changes during Early Postmortem Aging of Donkey Meat.

Metabolic changes in donkey meat during the early postmortem period have not been previously reported. The LC-MS-based metabolomics technique was conducted to understand the metabolic profiles and identify the key metabolites of donkey meat in the first 48 h postmortem. The pH values showed a decreasing trend followed by an increasing trend. Shear force was the lowest at 4 h and the highest at 24 h (p < 0.05). For the metabolome, some candidate biomarker metabolites were identified, such as adenine, inosine, n-acetylhistidine, citric acid, isocitrate, and malic acid. Predominant metabolic pathways, such as citrate cycle (TCA cycle), alanine, aspartate and glutamate metabolism, and purine metabolism, were affected by aging time. Overabundant n-acetylhistidine was identified in LT, declined at 12 h postmortem aging, and then increased. This may explain the significantly lower pH at 12 h postmortem. Adenine was higher at 4 h postmortem, then declined. Decreased ADP may indicate a fast consumption of ATP and subsequent purine metabolism in donkey meat. The results of this study provided new insights into early postmortem aging of donkey meat quality.

Characterization of lipids and volatile compounds in boiled donkey meat by lipidomics and volatilomics.

Lipids are crucial substances for the formation and retention of volatile compounds (VOCs). The lipid and VOC profiles of boiled donkey meat were investigated by lipidomics and volatilomics. In total, 4277 lipids belonging to 39 subclasses were identified, comprising 26.93% triglycerides (TGs), 15.74% phosphatidylcholins (PCs), and 9.40% phosphatidylethanolamines. The relative percentage of TG in the meat significantly decreases (p<0.001) from 0 to 40min, after which there is no significant change, whereas PCs, sphingomyelins, and methyl phosphatidylcholines (MePCs) show the opposite trend. TG(16:1_18:1_18:2) and TG(16:0_16:1_18:2) appear to be key lipids for retaining VOCs in boiled donkey meat. Furthermore, PC(18:3e_16:0) and MePC(31:0e) were found to be potential markers for discriminating donkey meat. A total of 83 VOCs were detected, including 25.30% aldehydes, 18.07% hydrocarbons, 14.46% ketones, and 13.25% alcohols. Eleven characteristic VOCs with relative odor activity values >1 were identified as the predominant flavor compounds in boiled donkey meat, mainly hexanal and 1-octen-3-ol. Of the 258 differential lipids, 72 of them, especially polyunsaturated-fatty acid-rich lipids, are the main contributors to the formation of VOCs. Together, the key lipids for retention and formation of VOCs in donkey meat were revealed, providing a theoretical basis for VOC regulation.

Comparative Study of Carcass Characteristics and Meat Quality of Local Mediterranean Donkey Breeds.

This study aimed to evaluate carcass and meat quality traits in Masri (n = 14) and North African (n = 14) male donkeys, raised in a semi-intensive breeding system, grazing on mountainous areas, with supplementation of 1 kg of barley per day per animal, slaughtered at 5 (±0.48) years old. Compared to Masri, the North African population exhibited higher (p < 0.05) final body weights (181.7 ± 2.1 and 212.5 ± 7.6 kg) and cold carcass weights (101.7 ± 1.3 and 116.2 ± 4.5 kg), but lower (p < 0.05) cold dressing percentages (56.0 ± 0.4 and 54.6 ± 0.4%). Meat quality analyses showed higher (p < 0.05) cooking loss values in Masri meat (43.9 ± 0.8 vs. 39.9 ± 1.2%). Among the meat color parameters, the hue value was higher (p < 0.05) in North African samples (0.42 ± 0.01 vs. 0.39 ± 0.1). Meat from North African donkeys had higher (p < 0.05) dry matter, fat, and protein contents. Meat amino acid analysis revealed abundant levels of lysine, leucine, and methionine, in both populations. Donkey meat from both populations presented a high polyunsaturated fatty acids content, resulting in polyunsaturated fatty acids/saturated fatty acids and omega 6/omega 3 ratios for all breeds close to the recommended values for human health. Atherogenic and thrombogenic indices were also suggested to have positive effects on consumers' artery health. The characteristics of donkey meat present intriguing nutritional aspects compared to ruminant meat, and its production should be encouraged in the rural development of inner-Mediterranean areas.

Characterization of Volatile Compounds in Donkey Meat by Gas Chromatography-Ion Mobility Spectrometry (GC-IMS) Combined with Chemometrics.

Volatile compounds (VOCs) are an important factor affecting meat quality. However, the characteristic VOCs in different parts of donkey meat remain unknown. Accordingly, this study represents a preliminary investigation of VOCs to differentiate between different cuts of donkey meat by using headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) combined with chemometrics analysis. The results showed that the 31 VOCs identified in donkey meat, ketones, alcohols, aldehydes, and esters were the predominant categories. A total of 10 VOCs with relative odor activity values ≥1 were found to be characteristic of donkey meat, including pentanone, hexanal, nonanal, octanal, and 3-methylbutanal. The VOC profiles in different parts of donkey meat were well differentiated using three- and two-dimensional fingerprint maps. Nine differential VOCs that represent potential markers to discriminate different parts of donkey meat were identified by chemometrics analysis. These include 2-butanone, 2-pentanone, and 2-heptanone. Thus, the VOC profiles in donkey meat and specific VOCs in different parts of donkey meat were revealed by HS-GC-IMS combined with chemometrics, whcih provided a basis and method of investigating the characteristic VOCs and quality control of donkey meat.

Factors affecting the quality and nutritional value of donkey meat: a comprehensive review.

Donkey meat is characterized by a high content of proteins, essential amino acids, and unsaturated fatty acids and is low in fat, cholesterol, and calories. Thus, it is considered a high-quality source of meat. Based on the data from PubMed and Web of science within past 10 years, this review summarizes the factors affecting the quality of donkey meat and its nutritional value, including breed, genetics, gender, age, muscle type, feeding regimen, storage and processing conditions. Breed, gender, age, and feeding regimen mainly affect the quality of donkey meat by influencing its intramuscular fat content and carcass quality. Meanwhile, the tenderness and flavor of donkey meat depend on the muscle type, storage and processing conditions. Genetics, on the other hand, fundamentally affect donkey meat quality by influencing the polymorphism of genes. These findings provide valuable insights and guidance for producers, consumers, and decision-makers in the donkey meat industry, promoting the development of more effective marketing strategies and the improvement of meat quality, thereby enabling the expansion and progress of the entire industry.

Enhancing Physicochemical Characteristics of Donkey Meat through High‐Voltage Electrostatic Stimulation during Acid Excretion

To investigate the impact of high‐voltage electrostatic stimulation on the quality of donkey meat, ten 30‐month‐old Dezhou donkeys (each weighing 250 ± 50 kg) were selected. Following slaughter, longissimus dorsi (LD) samples from both left and right carcasses were collected. The control group refrigerated the right muscle in a 0–4°C refrigerator for normal acid excretion. Meanwhile, the high‐voltage electrostatic group subjected the left muscle to high‐voltage electrostatic stimulation (30000 V) for 60 s before refrigerating it in the same conditions for acid excretion. The study showed that at the 1st, 6th, and 24th h of acid excretion, the high‐voltage electrostatic group exhibited significantly lower pH levels than the control group (P&lt;0.05). Furthermore, a∗ values in the high‐voltage electrostatic group showed an increasing trend relative to the control group at the 6th and 24th h of acid excretion (P = 0.0751, P = 0.0860). With increasing acid excretion time, both treatment groups displayed increased PV and TBARS values. At 48 and 72 h, the PV values in the high‐voltage electrostatic group were significantly lower than those in the control group (P &lt; 0.05). As acid excretion time increased, T‐AOC, SOD, and GSH‐Px in both groups decreased. However, the high‐voltage electrostatic group consistently exhibited higher antioxidant enzyme activity than the control group at all time points. SOD and GSH‐Px activity in the high‐voltage electrostatic group showed an increasing trend at 48 h of acid excretion (P = 0.0838, P = 0.0860). At 72nd h of acid excretion, the shear force of donkey meat in the high‐voltage electrostatic group was significantly lower than that in the ordinary treatment group (P &lt; 0.05). With increasing acid excretion time, the MFI of both treatment groups gradually increased. In particular, at the 1st and 48th h of acid excretion, the MFI of the high‐voltage electrostatic group was significantly higher than that of the ordinary treatment group (P &lt; 0.05). Following high‐voltage electrostatic stimulation, ultrastructure images of donkey meat at 6 and 72 h revealed numerous contractions and stretching bands. Therefore, this stimulation significantly improved the tenderness of donkey meat, reduced the oxidation rate of donkey meat, and improved the quality of donkey meat.

Study on the suitability of life cycle assessment for the estimation of donkey milk environmental impact

In the last decades, western Countries increased their interest in innovative products like donkey milk and other activities carried out with donkeys (onotherapy, onotourism). Donkey milk is considered a high-added-value food and is very similar to human breast milk. It is also used as an ingredient in cosmetics. The growing public interest suggests the need for a pilot study on the sustainability of donkey milk production, according to Life Cycle Assessment (LCA) criteria. Milk was used as the Declared Functional Unit (DFU) and two different models were described, a Real Scenario Model (RSM, i.e. a farm with its declared milk yield), and an Increased Milk Production Model (IMPM, i.e., the same farm with theoretically increased milk yield). Allocation was applied both in RSM and IMPM; thus, different values of impact categories, i.e., Global Warming Potential (GWP, kg CO2 equivalents), Acidification Potential (ACP, g SO2 equivalents) and Eutrophication Potential (EUP, g PO43−) were observed. GWP improved after mass allocation and showed the lowest equivalents in IMPM, compared to economic and reference allocation criterion (P < 0.05). In RSM, allocations affected GWP in a different way: the smaller size of the DFU resulted in the largest estimation of CO2 equivalents (P < 0.05) for reference allocation, whereas the mass allocation estimates were lower than with economic allocation (P < 0.05). ACP and EUP followed the same trends. No differences were found in IMPM results across the three allocation methods used. Moreover, mass allocation values recorded in RSM did not significantly differ from IMPM. ACP and EUP of RSM improved after economic allocation, although they were less sustainable (P < 0.05) than all IMPM values and RSM equivalents after mass allocation (P < 0.05). As expected, the theoretical model with increased milk yield improved the sustainability of the system. Both scenarios were affected by allocation criteria. In RSM, the economic and mass allocations described a representative scenario where donkey meat contributed to subtracting equivalents from milk (the main product). The present paper is a pilot study estimating for the first time the environmental impact of donkey milk production, with the aim to stimulate further research.

Yeast polysaccharide supplementation: impact on lactation, growth, immunity, and gut microbiota in Dezhou donkeys.

The Dezhou donkey, a prominent Chinese breed, is known for its remarkable size, rapid growth, and resilience to tough feeding conditions, and disease resistance. These traits are crucial in meeting the growing demand for Ejiao and donkey meat. Yeast polysaccharide (YPS), a functional polysaccharide complex known for its immune-enhancing and growth-promoting properties in livestock and poultry, remains relatively understudied in donkeys. This study aimed to investigate the impact of YPS supplementation on lactating and growing Dezhou donkey jennies and foals. Twelve 45-day-old Dezhou donkey foals and their jennies, matched for body weight and age, were randomly allocated to two dietary groups: a control group receiving a basal diet and an experimental group receiving the basal diet supplemented with 10 g/pen of YPS. The experiment was conducted over a 23-day period, during which donkey foals and lactating jennies were co-housed. The findings revealed that YPS supplementation had no adverse effects on milk production or composition in Dezhou donkey jennies but significantly increased feed intake. Additionally, YPS was associated with increased plasma glucose and creatinine concentrations in foals, while tending to decrease alkaline phosphatase, white blood cell count, red blood cell count, and hemoglobin levels (p < 0.10). Immune indices demonstrated that YPS supplementation elevated the levels of immunoglobulin A (IgA) and immunoglobulin G (IgG) in jennies (p < 0.05) and increased complement component C4 concentrations in foals (p < 0.05). Moreover, YPS positively influenced the fecal microbiome, promoting the abundance of beneficial microorganisms such as Lactobacillus and Prevotella in donkey foals and Terriporobacter and Cellulosilyticum in jennies, all of which contribute to enhanced feed digestion. Additionally, YPS induced alterations in the plasma metabolome for both jennies and foals, with a predominant presence of lipids and lipid-like molecules. Notably, YPS increased the concentrations of specific lipid metabolites, including 13,14-Dihydro PGF2a, 2-Isopropylmalic acid, 2,3-Dinor-TXB2, Triterpenoids, Taurocholic acid, and 3b-Allotetrahydrocortisol, all of which are associated with improved animal growth. In conclusion, this study suggests that dietary supplementation of YPS enhances feed intake, boosts immunity by increasing immunoglobulin levels, stimulates the growth-promoting gut microbiota (Lactobacillus and Prevotella), and exerts no adverse effects on the metabolism of both Dezhou donkey jennies and foals.

Comparison of Lipids and Volatile Compounds in Dezhou Donkey Meat with High and Low Intramuscular Fat Content.

The intramuscular fat (IMF) content is considered an important factor for assessing meat quality, and is highly related to meat flavor. However, in donkey meat, the influences of IMF content on lipid and volatile profiles remain unclear. Thus, we conducted lipidomic and volatilomic investigations on high- and low-IMF samples from donkey longissimus dorsi muscle. When the IMF level increased, the monounsaturated fatty acid (especially oleic acid) content significantly increased but the saturated fatty acid content decreased (p < 0.05). Twenty-nine of 876 lipids showed significant differences between the two groups. Volatile profiles from differential IMF content samples were also distinct. Five differential volatile odorants were identified in the two groups: 2-acetyl-2-thiazoline, octanal, 2-pentylfuran, pentanal, and 1-(2-pyridinyl) ethanone. Additionally, strong correlations were found between differential fatty acids and lipids with differential odorants. Thus, the difference in volatile odorants may result from the change in the fatty acid composition and lipid profiles induced by different IMF contents, highlighting the urgent need to increase IMF levels in donkey meat.

A novel SNP in NKX1-2 gene is associated with carcass traits in Dezhou donkey

BackgroundAt present, donkey meat in the market shows an imbalance between supply and demand, and there is an urgent need to cultivate a meat-type Dezhou donkey breed. On the one hand, it can improve the imbalance in the market, and on the other hand, it can promote the rapid development of the donkey industry. This study aimed to reveal significant genetic variation in the NK1 homeobox 2 gene (NKX1-2) of Dezhou donkeys and investigate the association between genotype and body size in Dezhou donkeys.ResultsIn this study, a SNP (g.54704925 A > G) was identified at the exon4 by high-depth resequencing of the Dezhou donkey NKX1-2 gene. The AA genotype is the dominant genotype. The g.54704925 A > G site was significantly associated with body length, thoracic girth, and hide weight (P < 0.05), while it was highly significantly associated with body height and carcass weight (P < 0.01) in Dezhou donkeys.ConclusionOverall, the results of this study showed that the NKX1-2 gene could be a candidate gene for breeding meat-type Dezhou donkeys, and the g.54704925 A > G locus could be used as a marker locus for selection and breeding.

Identification of horse, donkey and pig ingredients by species-specific ERA-based methods to assess the authenticity of meat products

Ensuring the authenticity of horse-, donkey- and pig-related meat products is of great religious and economic significance. In this study, with the mitochondrial genes of ATPase 6 or ND2 as targets, the species-specific real-time enzymatic recombinase amplification (real-time ERA) and ERA combined with lateral flow strip (LFS ERA) assays for horse, donkey and pig ingredients were developed. The optimization results showed that both ERA assays had the same optimal temperature for the detection of horse, donkey and pig ingredients, i.e., 39 °C for real-time ERA and 37 °C for LFS ERA, respectively. The assays could be performed simultaneously and the results could obtained within 25 min. Both developed assays showed good specificity and no cross-reactions with other common meat species were observed. The limit of detection of the developed ERA assays for horse, donkey and pig ingredients was 10 pg genomic DNA/per reaction and 0.1% target meat (w/w). Their applicability were verified with 45 donkey meat products (both raw and marinated minced meat), and the results showed that the detection rate of horse or pig ingredient was as high as 53.33%, including a complete substitution or partial substitution of donkey meat. The results were consistent with those of the standard real-time PCR in China, but the whole detection time was significantly reduced from 2 h to 35 min. It is concluded that the developed real-time ERA and LFS ERA assays are feasible for the rapid authentication of horse, donkey and pig meats and identification of the adulteration of donkey meat-related products.

Characterization of donkey-meat flavor profiles by GC-IMS and multivariate analysis.

The distinctive flavor compounds of donkey meat are unknown. Accordingly, in the present study, the volatile compounds (VOCs) in the meat from SanFen (SF) and WuTou (WT) donkeys were comprehensively analyzed by gas chromatography-ion mobility spectrometry (GC-IMS) combined with multivariate analysis. A total of 38 VOCs, of which 33.33% were ketones, 28.89% were alcohols, 20.00% were aldehydes, and 2.22% were heterocycles, were identified. Ketones and alcohols were significantly more abundant for SF than for WT, whereas aldehydes showed the opposite trend. The donkey meats from the two strains were well differentiated using topographic plots, VOC fingerprinting, and multivariate analysis. A total of 17 different VOCs were identified as potential markers for distinguishing the different strains, including hexanal-m, 3-octenal, oct-1-en-3-ol, and pentanal-d. These results indicate that GC-IMS combined with multivariate analysis is a convenient and powerful method for characterizing and discriminating donkey meat.

The value of donkeys to livelihood provision in northern Ghana.

Increased demand for the supply of donkey hides for use in the Traditional Chinese Medicine e'jiao, is leading to a re-appraisal of donkeys' contributions to livelihoods across the world. This research aimed to understand the utilitarian value donkeys provide to poor small holder farmers, especially women, in their efforts to make a living in two rural communities in northern Ghana. Uniquely, children and donkey butchers were interviewed for the first time about their donkeys. A qualitative thematic analysis was undertaken of data disaggregated by sex, age and donkey-ownership. The majority of protocols were repeated during a second visit, ensuring comparative data between one wet, and one dry season. Donkeys are more important in people's lives than had previously been recognised and are highly valued by their owners for their help in reducing drudgery and the multi-functional services they offer. Hiring out donkeys to generate income is a secondary role for people who own donkeys, especially women. However, for financial and cultural reasons the way donkeys are kept results in the loss of a certain percentage of the animals to the donkey meat market, as well as the global hides trade. Increasing demand for donkey meat, coupled with increasing demand for donkeys for farming, is leading to donkey price inflation and theft of donkeys. This is putting pressure on the donkey population of neighbouring Burkina Faso and pricing resource-poor non-donkey owners out of the market. E'jiao has put the spotlight on the value of dead donkeys for the first time, especially to governments and middlemen. This study shows that the value of live donkeys to poor farming households is substantial. It attempts to understand and document this value thoroughly, should the majority of donkeys in West Africa be rounded up and slaughtered for the value of their meat and skin instead.

Modified, innovative method for detection of adulteration of meat pro­ducts with meat of other species

The aim of this study was to detect illegal adulteration of beef meat products with meat from other species. Samples (n=120) of industrial and handmade beef products were randomly collected from retail outlets in Assiut city, Egypt: raw beef burger, oriental beef sausage, beef kofta, and beef luncheon (30 samples each). Samples were analysed using agar gel immunodiffusion (AGID) and modified AGID (MAGID) assays. Results showed that 17.5% of examined products were adulterated with chicken meat. MAGID detected that 14.1% of samples were adulterated with donkey meat, whereas all AGID results were negative. Human tissue was detected in 8.3% (AGID) and 10% (MAGID) of examined samples. Histological examination was then used to detect foreign tissue, and all categories of products were found to be adulterated, and some of them - contaminated with human blood cells. Polymerase chain reaction analysis confirmed that MAGID was more accurate and sensitive than AGID, especially for false negative AGID results. Consumers are advised not to consume too much of the studied meat products to avoid exposure to adulterated or contaminated products that might constitute a health hazard.

Forensic analysis of raw meat adulteration using mtDNA

Meat species identification has become essential with the increasing events of frauds like the illegal slaughter of cows, meat adulteration, and substitution. Food scam directly influences public well-being, trade, and wildlife. In Pakistan, donkey meat is used as adulterants for cow meat and is considered Haram in Islamic concepts. In this study PCR, based detection methods are used for identification purposes. The mitochondrial gene cytochrome b has been used in this study to identify the origin of meat specie. Specie-specific primers of cyt b of cow and donkey were used for identification. DNA from different binary ratios of cow and donkey meat was extracted by the phenol-chloroform method. Ratios were made from 1-10 and extracted DNA was subjected to PCR to amplify the target fragment of the cyt b gene. Primers were sensitive to identifying species origin in all meat ratios. Multiplex PCR was designed to identify both species and the results were analyzed by gel electrophoresis. Fragment size of 309bp for cow and 475bp for donkey was observed. Results of the current study conclude that PCR assays, including multiplex PCR, is efficient and has a high sensitivity for even small amount of meat. It is concluded that multiplex PCR is useful and reliable for adulterated meat detection.

Comparative transcriptome and proteome analyses of the longissimus dorsi muscle for explaining the difference between donkey meat and other meats

Domestic donkeys (Equus asinus) have been maintained mainly for service purposes in the past. Nowadays, there is an increasing interest in donkey milk and meat production in several countries, including China. Donkey meat is highly consumed because of its nutritional value and unique flavor. However, genomic studies on donkey meat are limited. Therefore, in this study, we aimed to examine the molecular difference of longissimus dorsi muscles of donkey, cow, and goat. RNA sequencing and Proteome sequencing technology were used to analyze the transcriptome and proteome of the longissimus dorsi muscle of donkey, cow, and goat. A total of 1338 and 1780 differentially expressed genes (DEGs) were identified in donkey meat compared with that in cow and goat meat, respectively. Most of the DEGs were involved in biological processes, including small GTPase-mediated signal transduction, protein ubiquitination, protein glycosylation, and MAP kinase tyrosine/serine/threonine phosphatase activity. Additionally, 764 and 1024 differentially expressed proteins (DEPs) were identified in cow vs. donkey, and goat vs. donkey, respectively; these DEPs were mainly involved in metabolism. Genetic variation and regulatory factors can combine as a database to provide more valuable molecular information for further analysis.

First insights about the underlying mechanisms of Martina Franca donkey meat tenderization during aging: A proteomic approach

This study aimed to evaluate the effect of different aging times (1, 6 and 14 days) on the tenderization rate and protein changes in ten Martina Franca donkey striploins using a proteomic approach. During aging, a progressive decrease in share force, hardness, gumminess, and chewiness together with an increase in myofibril fragmentation index were observed. Proteolysis monitored by immunoblotting revealed a progressive degradation of desmin and fast troponin-T over time and an increase of their degradation products up to 14 days aging. Proteomics revealed by means of two-dimensional electrophoresis 37 protein spots corresponding to 15 proteins to change significantly by increasing aging time. These proteins belong to three pathways, these being “muscle contraction, structure, and associated proteins” (9 proteins); ii) “energy metabolism” (5 proteins); and iii) “chaperone” (1 protein). This study is the first to highlight the possible role of interconnected pathways in driving the final quality of donkey meat and predicting its texture.