Equid milk for human consumption

Effects of lysine and threonine on milk yield, amino acid metabolism, and fecal microbiota of Yili lactating mares

The nutritional benefits of mare milk are attracting increasing consumer interest. Limited availability due to low yield poses a challenge for widespread adoption. Although lysine and threonine are often used to enhance protein synthesis and muscle mass in horses, their impact on mare milk yield and nutrient composition remains underexplored. This study investigated the effects of lysine and threonine supplementation on 24 healthy Yili mares, mares at day 30 of lactation, over a 120-day period. The mares were divided into control and three experimental groups (six mares each) under pure grazing conditions. The control group received no amino acid supplementation, while experimental groups received varying daily doses of lysine and threonine: Group I (40 g lysine + 20 g threonine), Group II (60 g lysine + 40 g threonine), and Group III (80 g lysine + 60 g threonine). Supplementation in Group II notably increased milk yield, while Groups I and II showed higher milk fat percentages, and all experimental groups exhibited improved milk protein percentages. Additionally, blood levels of total protein, albumin, triglycerides, and glucose were reduced. Detailed analyses from Group II at peak lactation (day 60) included targeted metabolomics and microbial sequencing of milk, blood, and fecal samples. Amino acid metabolomics assessed amino acid content in mare milk and serum, while 16S rRNA gene sequencing evaluated rectal microbial composition. The results indicated that lysine and threonine supplementation significantly increased levels of threonine and creatine in the blood, and lysine, threonine, glutamine, and alanine in mare milk. Microbial analysis revealed a higher prevalence of certain bacterial families and genera, including Prevotellaceae, p_251_o5, and Rikenellaceae at the family level, and unclassified_p_251_o5, Prevotellaceae_UCG_001, and Rikenellaceae_RC9_gut_group at the genus level. Multi-omics analysis showed positive correlations between specific fecal genera and amino acids in mare milk. For instance, Prevotellaceae_UCG_003, unclassified Bacteroidetes_BS11_gut_group, and Corynebacterium were positively correlated with lysine, while unclassified Prevotellaceae was positively correlated with alanine and threonine, and Unclassified_Bacteroidales_BS11_gut_group was positively correlated with glutamine. In summary, lysine and threonine supplementation in grazing lactating mares enhanced milk production and improved milk protein and fat quality. It is recommended that herders, veterinarians, and technicians consider amino acid content in the diet of lactating mares. The optimal supplementation levels under grazing conditions for Yili horses were determined to be 60 g lysine and 40 g threonine per day. Future research should explore the molecular mechanisms by which these amino acids influence milk protein and lipid synthesis in mare mammary epithelial cells.

Report on a Milking Mule: Milk Qualitative Characteristics during Lactation

Despite their inability to reproduce naturally, mules can host embryos and be surrogate dams. The aim of this investigation was to increase our knowledge of the qualitative composition of mule's milk and its variations throughout the whole lactation period-namely, from 6 h after foaling to 180 days in milk (DIM). Milk was obtained from a mule dam that had foaled after receiving a mule embryo transfer. For each sample, the gross, mineral, and fatty acid composition was evaluated. The average quality of the mule milk was as follows: protein 1.97 g 100 mL-1, fat 0.90 g 100 mL-1, and ash 0.39 g 100 mL-1. Saturated fatty acids made up, on average, 50.00 g 100 g-1 of fat. Monounsaturated and polyunsaturated fatty acids made up half of the total fatty acid content (31.80 g 100 g-1 and 18.2 g 100 g-1 of fat, respectively). Linoleic acid and linolenic acid were the main polyunsaturated fatty acids in the milk. The milk composition changed throughout lactation. Dry matter, protein, fat, and ash decreased significantly from early lactation (6 h to 14 DIM). The n3 polyunsaturated fatty acids decreased at the end of lactation. The changes in milk composition throughout lactation are probably due to adaptations to the growth requirements of the foal.

Nutritional Quality and Socio-Ecological Benefits of Mare Milk Produced under Grazing Management

This review discusses the scientific evidence that supports the nutritional value of mare milk and how its properties are essentially achieved when mares are managed under grazing conditions. Mare milk's similarity with the chemical composition of human milk makes this food and its derived products not only suitable for human consumption but also an interesting food regarding human health. The contribution of horse breeding under grazing management to other socio-ecological benefits generated by equine farms is also highlighted. Both the high added value of mare milk and the socio-ecological benefits derived from pasture-based systems could be explored to improve the performance of equine farms located in arid and semi-arid areas or in regions with moderately harsh environmental conditions as equids have a strong adaptation capacity.

Fermented Mare Milk and Its Microorganisms for Human Consumption and Health

Mare milk is consumed by approximatively 30 million people in the world. In countries in Asia and East Europe, mare milk is mainly consumed as source of fermented products, called koumiss, airag or chigee, alcoholic beverages obtained by means of a culture of bacteria and lactose-fermenting yeasts. Recent research concerning mare milk and its derivatives deals mainly with their potential employment for human health. Studies about the isolation and characterization of Lactobacillus spp. and yeasts from koumiss have been aimed at assessing the potential functional properties of these micro-organisms and to find their employment for the industrial processing of mare milk. The aim of this literature review is to summarize recent research about microorganisms in fermented mare milk products and their potential functional properties.

Increasing the milk productivity of Kazakh jabe horses

The purpose of the study was to determine the milk productivity and chemical composition of the milk of mares of the Kazakh breed of the jabe type (KJ) and the Novoaltay-Kazakh crossbreeds of the 1st generation (NA x KJ) in the conditions of herd keeping. To determine the milk productivity of mares, 2 experimental groups were formed with a total of 30 mares, 15 individuals were selected in each group. The studied animals were formed according to the principle of pairs of analogues in the context of full-age groups from 5 to 11 years. Kazakh horses of the jabe type in the group of experimental mares in milk have an average live weight of 433.5 kg, and are significantly inferior to the Novoaltay-Kazakh crosses (515.3 kg). The body measurements were 142.0-149.0-174.9-18.2 cm in Kazakh horses of the jabe type, and 150.1-157.1-186.7-20.02 cm, respectively, in Novoaltay-Kazakh crossbreeds. According to the results of studies, the milkiness of mares of the Novoaltay-Kazakh crosses for 105 days of lactation averaged 1932 liters or higher by 25.2% (487.2 liters) than the milkiness of mares of the Kazakh breed of the jabe type. As a result of studies on the composition of milk of mares of different genotypes, it was found that in mares of Kazakh jabe, on average, protein and fat indicators compared to Novoaltay-Kazakh crossbreeds were higher by 0.07% and 0.05%. In the course of determining the live weight of mares among the experimental groups, it was found that the Novoaltay-Kazakh crossbreeds, on average, had a higher live weight of 515.3 kg or higher compared to the Kazakh jabe by 81.8 kg (15.8%). Thus, the studies have proved the prospects of using stallions of the Novoaltay breed to increase the milkiness of local Kazakh horses of the jabe type in herd and pasture conditions.

Milk from Halari Donkey Breed: Nutritional Analysis, Vitamins, Minerals, and Amino Acids Profiling

This current research set out to characterize Halari donkey milk by investigating its nutritional constituents, including its proximate analysis, water activity, titratable acidity, energy, and microbiological analysis. A comprehensive profiling of vitamins, minerals, and amino acids was also carried out. It was found that the composition of Halari donkey milk was consistent with previously published donkey milk literature and was comparable to that of human milk. Halari donkey milk has low 0.86 ± 0.04% fat content, 2.03 ± 0.03% protein content, 0.51 ± 0.05% ash content, and high 5.75 ± 0.15% lactose content making it sweet and palatable. The energy content of Halari donkey milk was 40.39 ± 0.31 kcal/100 g, and the water activity ranged from 0.973 to 0.975. Titratable acidity was 0.03 ± 0.01%. Halari donkey milk can be considered acceptable and microbiologically safe, having low total plate count and yeast and mould counts. Mineral testing revealed that Halari donkey milk included significant amounts of magnesium, sodium, calcium, potassium, phosphorus, and zinc. The concentration of different vitamins and amino acids such as isoleucine and valine also contribute to the nutritional value of Halari donkey milk.

Chemical composition, whey protein profile, and fatty acid profile of milk from Sokólski horses in relation to Polish Halfbred horses

The study was carried out on milk from cold-blooded Sokólski mares and warm-blooded Polish Halfbred mares. Milk samples were analysed for content of dry matter, protein, fat, lactose, and ash; density; energy value; percentage of α-lactalbumin (α-La), β-lactoglobulin (β-Lg), serum albumin (SA), immunoglobulin (Ig), lactoferrin (Lf) and lysozyme (Lz) in the total protein; and fatty acid profile. Milk from cold-blooded mares was found to be similar in protein and fat content to that of warm-blooded mares, but had higher content of dry matter, including lactose and ash. It also had significantly (P≤0.01) higher content of α-La, SA and Lz, and lower content of β-Lg, Ig and Lf in comparison to milk from warm-blooded mares. Milk from Sokólski horses had a significantly (P≤0.01) higher proportion of SFA, including C10:0, C12:0, C14:0, C16:0 (P≤0.01) and C18:0 (P≤0.05), while the milk of warm-blooded mares had a significantly (P≤0.01) higher proportion of MUFA, including C16:1n-9 and C18:n-9, and PUFA, including C18:2n-6 and C18:3n3. The share of n-6 and n-3 PUFA was significantly (P≤0.01) higher in milk from warm-blooded horses, but their ratio (n-6/n-3) was lower (more favourable) in milk from cold-blooded mares. In addition, milk from warm-blooded horses had a lower (P≤0.01) share of HSFA and a higher proportion of DFA compared to cold-blooded horses, as well as lower values for AI and TI. Despite these minor differences in comparison with warm-blooded mares (Polish Halfbred), milk from cold-blooded Sokólski mares was shown to be a food product of high nutritional value, which is one argument in favour of the use of this horse breed for dairy purposes.

Microbiological Quality of Raw Donkey Milk from Serbia and Its Antibacterial Properties at Pre-Cooling Temperature

The aim of this study was to examine the microbiological quality of raw donkey milk of an indigenous Serbian breed as well as the changes in the microbial populations during storage at 4 °C. In addition, antibacterial activity of donkey milk against E. coli, L. monocytogenes and S. aureus at 15 °C as well as the content of the two main antibacterial proteins lysozyme and lactoferrin were investigated. Microbiological examination of 137 individual milk samples collected over a period of 21 months showed good microbiological quality since foodborne pathogens such as Salmonella spp. and L. monocytogenes were not detected in any of the analyzed samples, while the number of E. coli, Enterobacteriaceae, total coliform bacteria, sulfite-reducing Clostridia and aerobic sporogenic bacteria was below the limit of quantification (<1 cfu mL^-1). During the six-days storage at 4 °C, total bacterial counts and the counts of lactic acid bacteria remained at the initial level while pathogenic bacteria were not detected. The strongest antibacterial activity of the tested milk was observed against E. coli, while S. aureus was the least sensitive to milk antibacterial compounds. Although further research is needed to fully elucidate the antibacterial mechanism and synergistic activity of different compounds in donkey milk, the high content lysozyme (2.63 ± 0.03 g L^-1) and lactoferrin (15.48 mg L^-1) observed in tested milk could contribute to its strong antibacterial activity and extension of the storage period during which it can be safely consumed.

Nutritional Parameters in Colostrum of Different Mammalian Species

Colostrum (or first milk) is the food produced by all the mothers in all specific mammalian species, ruminants, monogastric and marine mammalians for their newborns during the first 24–48 h post-partum. Colostrum provides to the neonate all essential nutrients necessary for the first week of life, but the effect of colostrum shows a long-term effect not limited to these first days. Colostrum is considered to be a safe and essential food for human consumption. Some young children can show at the beginning of their colostrum-based diet some side effects, such as nausea and flatulence, but they disappear quickly. In human colostrum, the immunoglobulins and lactoferrin determined show the ability to create natural immunity in newborns, reducing greatly the mortality rate in children. Recent studies suggest that bovine colostrum (BC) may be an interesting nutraceutical food, due to its ability in preventing and/or mitigating several diseases in newborns and adults. This review aims to show the nutraceutical and functional properties of colostrum produced by several mammalian species, describing the different colostrum bio-active molecules and reporting the clinical trials aimed to determine colostrum nutraceutical and therapeutic characteristics in human nutrition.

Worldwide Research Trends on Milk Containing Only A2 β-Casein: A Bibliometric Study

Simple Summary

A1 β-casein has been correlated with adverse health outcomes, and, as a consequence, milk containing only A2 β-casein has emerged on the market. There has been a relevant increase in publications in this area since 2010. Food Science Technology and Agriculture were the main research areas of this topic. The term β-casomorphin was the most frequently used. The USA, New Zealand, and Australia were the most productive countries, though the most productive research institutions were, in absolute terms, from India, France, and Germany. The majority of the most cited studies that refer to A2 β-casein and health were reviews, and a few clinical trials have also been published.

Abstract

The protein fraction of β-casein may play a key role in the manifestation of a new intolerance: milk protein intolerance. The most common forms of β-casein among dairy cattle breeds are A1 and A2 β-casein. During gastrointestinal digestion of A1 β-casein, an opioid called peptide β-casomorphin-7 (BCM-7) is more frequently released, which can lead to adverse health outcomes. For that reason, novel products labelled as “A2 milk” or “A1-free dairy products” have appeared on the market. In this context, a bibliometric analysis on A2 β-casein research was carried out through the Web of Science (WoS) database. The main objective of this work was to provide an overview of the state of the art in the field of β-casein A2 by analyzing the number of publications per year, trends in thematic content, the most frequently used terms, and the most important institutions and countries in the field. This bibliometric study showed that a greater effort is needed to determine the possible implications of this novel product for human health and the market.

Histomorphometric changes of testicular tissues by season and age of Algerian local donkeys (Equus asinus)

The present investigation was undertaken to highlight the histomorphometric changes of testicular tissues according to season and age in donkeys (Equus asinus) under northern Algeria conditions. The experiment was conducted from February 2019 to January 2020. A total of 21 sexually mature donkeys were selected randomly. The testis were immediately collected after slaughter for the histological observation. The analysis of the correlation coefficients shows negative correlations between DL and other parameters such as DST, GCEH, TTA and ITSA, ranged between -0.24 and -0.79. Also, there were a high negative correlations between season and the histomorphometric parameters, except DL was revealed positive (r=0.65). On the other hand, there were positive correlations between age and testicular histomorphometrics parameters. The results indicated that DST, GCEH, TTA and ITSA values were significantly higher in winter and autumn seasons than in spring and summer seasons. It is also noteworthy that DST, GCEH, TTA and ITSA values were significantly higher in adult and aged donkeys than in young donkeys. Our comparative analysis of histological parameters, suggests that the sexual activity usually occurs during winter and autumn in local donkeys of Algeria. In addition, our results of histomorphometric of testicular tissues are correlated with age of donkeys.

Changes in the Fatty Acid Composition of Milk of Lipizzaner Mares during the Lactation Period

The composition and properties of the milk fat of mares’ milk is interesting from a nutritional standpoint. The aim of this study was to determine the nutritional value of Lipizzaner mare’s milk for possible human consumption and identity the influence of the parity and stage of lactation on its fatty acid (FA) composition. This study was conducted on 17 Lipizzaner mares from a state stud farm in the Slavonian region (eastern Croatia). Mares were hand-milked twice during lactation in the fourth and sixth months. Significantly higher contents of MUFAs (monounsaturated fatty acids) and PUFAs (polyunsaturated fatty acids) and lower ratios of n-6/n-3 were found in the fourth month of lactation. This parity significantly affected the PUFA/SFA ratio (polyunsaturated fatty acids/saturated fatty acids), with lower values found in older mares. The fatty acid composition of mare’s milk that is especially high in UFAs (unsaturated fatty acids) is considered to be beneficial for consumers.

Morphological, Immunohistochemical, and Ultrastructural Studies of the Donkey's Eye with Special Reference to the AFGF and ACE Expression

The donkey is mainly used as a working animal for riding and pack transport, as well as for dairy and meat production. Eye afflictions are common in donkeys, thus requiring a detailed study. A few studies had focused on the donkey's eye, and most of them had considered it, merely, a horse's eye. This study aimed to investigate the anatomy, histology, ultrastructure, and immunohistochemical features of the donkey's eye. The results were recorded and compared to those of horses in certain dimensions. Unlike horses, the donkey's eye is more circular in the contour of the cornea, has smaller lenticular thickness, and has longer anterior and vitreous chambers. Positive immunoreactivity to acidic fibroblast growth factor in the basal cell layers of the cornea was observed, indicating their role in cell differentiation and the renewal of the epithelium. Moreover, the corneal keratocytes expressed angiotensin-converting enzyme, which plays a role in corneal homeostasis and wound healing. Additionally, telocytes, hyalocytes, and other immune cells were observed within the iris and ciliary processes. Hence, this work is an updated detailed study of the morphology and ultrastructure of the donkey's eye and reveals some similarities and dissimilarities to the horse's eyes, which should be considered in clinical practice.

Mammary gland physiology and farm management of dairy mares and jennies

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The equid udder has a lower storage capacity than the ruminant udder.

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Milking frequency is one of the most important factors affecting milk yield.

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Foals can be partly artificially suckled during lactation.

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Mechanical milking has been used in equids but our understanding of machine milking remains poor.

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Automated milking systems for equids represent a great challenge for the future.

Equid milk is arousing increasing interest in consumers and researchers because of its similarity in composition to human milk. The low and different protein content makes equid milk it suitable for children with cow milk protein allergy. Both horse and milk production, in many farms, still follow a characteristic and traditional method of separating the foal from the mother to allow milking procedures. This separation lasts at least 2 to 3 h before milking, a time in which the foal remains fasting. This operation is repeated several times a day, as the equid udder has little collection capacity, and milking frequency is one of the most important parameters to increase milk production; it must be emptied often. New partial artificially suckling techniques have been developed that allow the foal to be separated from its mother for many hours without starving. Furthermore, mechanical milking has been introduced in equid milk production, although in-depth knowledge is lacking on milking parameters and how these aspects affect milk production and udder health. Moreover, in some farms, new milking parlors for Equidae have been developed, ensuring that stress is minimized and production and animal welfare are ensured. It is important to develop and apply technologies for equid milk production, evaluating potential effects on welfare, health, and milk production. This represents the broadest perspective and the greatest challenge because of the need to understand management best practices, thinking to the possibility to introduce as soon as possible automatic milking systems that could ensure a good milking frequency.

The Possibility of Including Donkey Meat and Milk in the Food Chain: A Southern African Scenario

Simple Summary

The demand for donkey products such as meat and milk has increased in recent years, as new information on the health benefits of the products is becoming more available. Recent nutritional trends have shown a preference for nutritional and functional foods, giving consumers more options to choose from. Donkey products are seen as valuable foods that contain appreciable nutraceutical properties. However, less information is available on their optimal management practices, and their level of introduction to the food chain remains minimal. Increasing awareness of the importance of donkey products will increase their productivity and accelerate the introduction of these products into the food chain. This review aims to document available information on donkey products and factors affecting their introduction into the food chain, quoting different scenarios from the Southern African region.

Abstract

Animal proteins are essential for the optimal growth and health of humans. Meat and milk are common sources of protein, mostly produced by ruminants. The agrarian challenges experienced around the world warrant sourcing alternative proteins from animals that can withstand harsh environmental conditions to produce quality proteins. Donkeys (Equus asinus) are known to survive on low husbandry and inferior quality forage to produce meat and milk, which have been used since ancient times. However, the commercialisation of these products has not flourished due to product scarcity, low production rates, and consumer preferences. Recent discoveries and the quest to look for alternative sources of protein have sparked studies on donkey products. In addition, milk and meat from donkeys have active ingredients that could also contribute to curing diseases. Donkey milk is believed to contain antioxidant, antimicrobial, antiproliferative, and antidiabetic properties. In many countries, particularly in Africa, the consumption of donkey meat and milk has not been fully adopted due to a lack of knowledge and legislation regarding production.

Milk Properties and Morphological Characteristics of the Donkey Mammary Gland for Development of an Adopted Milking Machine—A Review

Donkey milk (DM) has been known in the world for 5000 years for its benefits for human nutrition and health. Nowadays, DM has become more and more attractive as a commercial product. DM contains several physiologically functional components, including high-quality whey proteins, vitamins, important minerals, unsaturated fatty acid and bioactive components. Therefore, it is not only consumed as food but also as a remedy. The average daily milk yield of a female donkey over the entire lactation season was 1.57 ± 1.12 kg/day and fluctuated between 0.20 and 6.00 kg/day. Average milk concentrations (±SD) of fat, protein, lactose, total solids and ash in DM were 0.63 ± 0.41%, 1.71 ± 0.24%, 6.34 ± 0.37%, 9.11 ± 0.95% and 0.39 ± 0.04%, respectively. Interestingly, DM is similar in composition to mare’s milk, and both are similar to mother’s milk. The anatomical and morphological properties of the mammary gland of the female donkey are special and can be compared with those of mare udders. However, the cistern cavity of the mammary gland of female donkeys is characterized by the presence of multiple pockets that open directly into the teat, instead of a single cistern cavity. Therefore, the mammary gland capacity in donkey mare is low and milking technique and routine are of most importance. So far there is no special milking machine for female donkeys and mares. The milking machines used nowadays were initially designed for smaller sheep and goat udders. The company Siliconform, Germany, has set itself the task of developing an optimized milking machine for donkey mares, which is adapted to the anatomical and morphological properties of the donkey mammary gland. Furthermore, it should achieve a physiologically ideal milking process meeting high animal welfare standards for increased milk production with high quality standards.

Composition and aptitude for cheese-making of milk from cows, buffaloes, goats, sheep, dromedary camels, and donkeys

Bovines account for about 83% of the milk and dairy products consumed by humans worldwide, the rest represented by bubaline, caprine, ovine, camelid, and equine species, which are particularly important in areas of extensive pastoralism. Although milk is increasingly used for cheese production, the cheese-making efficiency of milk from the different species is not well known. This study compares the cheese-making ability of milk sampled from lactating females of the 6 dairy species in terms of milk composition, coagulation properties (using lactodynamography), curd-firming modeling, nutrients recovered in the curd, and cheese yield (through laboratory model-cheese production). Equine (donkey) milk had the lowest fat and protein content and did not coagulate after rennet addition. Buffalo and ewe milk yielded more fresh cheese (25.5 and 22.9%, respectively) than cow, goat, and dromedary milk (15.4, 11.9, and 13.8%, respectively). This was due to the greater fat and protein contents of the former species with respect to the latter, but also to the greater recovery of fat in the curd of bubaline (88.2%) than in the curd of camelid milk (55.0%) and consequent differences in the recoveries of milk total solids and energy in the curd; protein recovery, however, was much more similar across species (from 74.7% in dromedaries to 83.7% in bovine milk). Compared with bovine milk, the milk from the other Artiodactyla species coagulated more rapidly, reached curd firmness more quickly (especially ovine milk), had a more pronounced syneresis (especially caprine milk), had a greater potential asymptotical curd firmness (except dromedary and goat milk), and reached earlier maximum curd firmness (especially caprine and ovine milk). The maximum measured curd firmness was greater for bubaline and ovine milk, intermediate for bovine and caprine milk, and lower for camelid milk. The milk of all ruminant species can be used to make cheese, but, to improve efficiency, cheese-making procedures need to be optimized to take into account the large differences in their coagulation, curd-firming, and syneresis properties.

Role of genes related to performance and reproduction of Thoroughbreds in training and breeding - A review

Thoroughbreds have been selected for speed and stamina since the 1700s. This selection resulted in structural and functional system-wide adaptations that enhanced physiological characteristics for outstanding speed of 61-71 kph (38-44 mph) between 1,000 and 3,200 m (5 furlongs - 2 miles). At present, horseracing is still an economically important industrial sector, therefore intensive research is underway to explore genes that allow the utilisation of genetic abilities and are significant in breeding and training. This study aims to provide an overview of genetic research and its applicability related to Thoroughbreds.

Effects of donkey milk on oxidative stress and inflammatory response

Donkey milk is gaining interest as a natural nutritional and medicinal product, mainly because its composition is similar to that of human milk, and it has some potential biological properties, such as antioxidant, anti-inflammatory, antiaging, antimicrobial, and anticancer properties. Considering the increasing prevalence of several chronic diseases related to oxidative stress and inflammation and the multiple beneficial properties and nutritional value of donkey milk, an up-to-date review of the current studies related to the antioxidative and anti-inflammatory abilities of donkey milk is necessary. Therefore, this review aims to discuss the relationship between inflammation and oxidative stress; and to further systematically review the progress of recent research on donkey milk, mainly including its nutritional value and functional properties. Particularly, we highlighted the anti-inflammatory and antioxidative properties of donkey milk using in vitro model, animal model, and the potential role of donkey milk in alleviating some chronic diseases related to inflammation. PRACTICAL APPLICATIONS: This paper was conducted on anti-inflammation and antioxidant activities of donkey milk and its related products, in addition to a summary of the relationship between oxidative stress and inflammation and the value of donkey milk. Donkey milk and its related products have been shown to scavenge reactive oxygen species, activate the antioxidant system, enhance immune function, and maintain the balance of intestinal flora in in vitro and in vivo models. This paper should provide a better understanding of the influences of oxidative stress and inflammation on host health and the biological functions and application of donkey milk, and will provide a certain basis for the nutritional regulation of several chronic diseases related to oxidative stress and inflammation. However, the underlying mechanism is poorly understood. In addition, few clinical studies have been performed to establish its multiple benefits in humans. Further research is warranted to evaluate its impacts on health at molecular levels.

Effect of Topical Cyclopentolate 1% on Ocular Ultrasonographic Features, Intraocular Pressure, Tear Production, and Pupil Size in Normal Donkeys (Equus Asinus)

This study was performed to investigate the effects of cyclopentolate on ultrasonographic parameters of eye structures, intraocular pressure (IOP), tear production, and pupil size in normal donkeys. Sixteen eyes of eight clinically healthy adult donkeys (2-2.5 years old) weighing 295 ± 34 kg (mean ± standard deviation) were used in this study. Cyclopentolate hydrochloride 1% was instilled in a randomly selected eye and the other eye received normal saline drops as a control. The effect of cyclopentolate was evaluated by ultrasonography. Additionally, changes in IOP and tear production were evaluated for 2 hours post-instillation by tonometry and Schirmer tear test (STT), respectively. Vertical and horizontal pupil diameters were recorded pre-instillation (0), and 15, 30-, 45-, 60-, and 120-minutes post-instillation. After cyclopentolate 1% instillation, iridocorneal angle and width of the entry of ciliary cleft were significantly increased as observed by ultrasonography. IOP was significantly increased starting from 30 minutes till 60 minutes post-instillation of cyclopentolate 1%. Non-significant alteration in the STT was observed in the cyclopentolate-treated eyes compared to the control eyes. Both vertical and horizontal pupil diameters began to significantly increase 30 minutes after cyclopentolate 1% instillation compared to the control saline group. In conclusion, cyclopentolate 1% could be used as a potent cycloplegic drug in donkeys without systemic or ocular side effects.

A promising 31P NMR-multivariate analysis approach for the identification of milk phosphorylated metabolites and for rapid authentication of milk samples

A fast and reliable method for the identification of milk from different mammalians was developed by using ³¹P NMR metabolite profile of milk serum coupled to multivariate analysis (PCA and classification models UNEQ, SIMCA and K-NN). Ten milk samples from six different mammalians, relevant to human nutrition (human, cow, donkey, mare, goat, sheep), were analyzed and eight monophosphorylated components were identified and quantified: phosphocreatine (PCr), glycerophosphorylcholine (GPC), glycerophosphorylethanolamine (GPE), N-acetylglucosamine-1-phosphate (NAcGlu-1P), lactose-1-phosphate (Lac-1P), galactose-1-phosphate (Gal-1P), phosphorylcholine (PC), glucose-6-phosphate (Glu-6P). PCA showed interesting clustering based on the animal genus. K-NN can be successfully used to discriminate between donkey and cow samples while UNEQ class-modeling resulted more suitable for compliance verification. Results confirm the natural variability of milk samples among different species. These data highlight the great potentials of NMR/multivariate analysis combined method in the rapid analysis of phosphorylated milk serum metabolites for milk origin assessment and milk adulteration detection.

Nutritional Properties of Camelids and Equids Fresh and Fermented Milk

Milk is considered a complete food because all of the nutrients important to fulfill a newborn’s daily requirements are present, including vitamins and minerals, ensuring the correct growth rate. A large amount of global milk production is represented by cow, goat, and sheep milks; these species produce about 87% of the milk available all over the world. However, the milk obtained by minor dairy animal species is a basic food and an important family business in several parts of the world. Milk nutritional properties from a wide range of minor dairy animal species have not been totally determined. Hot temperatures and the lack of water and feed in some arid and semi-arid areas negatively affect dairy cows; in these countries, milk supply for local nomadic populations is provided by camels and dromedaries. The nutritional quality in the milk obtained from South American camelids has still not been completely investigated, the possibility of creating an economic resource for the people living in the Andean highlands must be evaluated. Both mare and donkey milks show a chemical composition very similar to human milk, and they represent a good replacer of cows’ milk for infants nutrition, especially for children affected by cow milk proteins allergy. In this review, differences and similarities in the quality parameters of milk from minor dairy animals, such as camelids and equids, have been compared.

Mare's Milk from a Small Polish Specialized Farm-Basic Chemical Composition, Fatty Acid Profile, and Healthy Lipid Indices

Simple Summary

As mare’s milk has high nutritional and biological value, it has a number of therapeutic properties. The aim of this study was to determine the basic composition, fatty acid profile, and values of health-related indices of milk from mares of different lactation stages, ages, and birth orders. The study was conducted on milk obtained from Coldblood mares in weeks 10, 15, and 25 of lactation. The mares were aged between five and 14 years. It was found that milk produced from the 15th week of lactation had the most beneficial fatty acid composition and very beneficial values of health-related indices (low values of the atherogenic index—AI and thrombogenic index—TI), which is important with regard to the prevention of atherosclerosis and thrombosis. Moreover, the study found a dependence between birth order and the atherogenic index, which was lower in milk derived from older mares (birth order > 7). The findings from the study indicate that it is possible to modify the fatty acid profile of milk by appropriately managing the age structure of the herd of mares, among other things. To confirm this dependence, the study will be continued on a larger group of mares.

Abstract

The objective of this study was to determine the chemical composition, fatty acid profile, and values of healthy indices of milk from a specialized farm of Polish Coldblood mares of different ages, birth orders, and lactation stages. Milk samples (n = 48) were collected for analysis in weeks 10, 15, and 25 of lactation from mares aged between five and 14 years. The study showed that the stage of lactation has a significant effect on the fatty acid (FA) profile of the milk produced on the farm. The highest concentration of monounsaturated and polyunsaturated FAs was found in milk produced from the 15th week of lactation. The milk was also characterized by low values of atherogenic and thrombogenic indices, which indicate the health benefits of milk with respect to the content of fatty acids and their potential to prevent or cause atherosclerosis and thrombosis. The study also found a significant correlation between the number of foalings (birth order), the fatty acid profile, and atherogenic index of milk produced on the farm. The findings from the study indicate that it is possible to modify the fatty acid profile of bulk tank milk through appropriate management of the age structure of the herd of mares. To confirm this dependence, the study will be continued on a larger group of mares.

Milk composition of white rhinoceros over lactation and comparison with other Perissodactyla

The proximate composition of milk from fifteen free-ranging white rhinoceroses at different lactation stages is reported with detailed analysis of fatty acid composition and minerals. Lactose is the main component at 7.93 ± 0.53%, followed by 0.93 ± 0.19% protein, 1.76 ± 0.39% fat, 0.40 ± 0.18% ash, 0.05 ± 0.01% glucose, and 0.04 ± 0.02% non protein nitrogen The interindividual variation of all the components is high, showing no trend of change over lactation. The K and P content decreased over lactation. The fatty acid composition of rhinoceros milk is characteristic with a high saturated fatty acids content of 62%-84%, of which the medium chain fatty acids form the major portion. The C10:0, C12:0, C16:0, and C18:1c9 are the major fatty acids in the milk fat. The results are compared with the two other Perissodactylae families, the Equidae and Tapiridae. Differences in gross composition are small, but the milk of the Rhinocerotidae have the lowest gross energy, while the milk fats consist of the highest amounts of saturated fatty acids, while the low levels of C16:1c9 and C18:1c9 indicate the lowest mammary Δ9-desaturase activity.

Vitamins in Human and Donkey Milk: Functional and Nutritional Role

BACKGROUND

Whole milk is a good source of all the nutrients, and it also contains a sufficient number of vitamins to permit regular the growth of the neonate. Dairy cow milk can create allergy in infants less than 12 months old because of the high caseins and β-lactoglobulin content. In these circumstances, donkey milk can represent a good replacement for dairy cows' milk in children affected by Cow Milk Protein Allergy (CMPA) because of its close chemical composition with human milk, mainly due to its low protein and low mineral content. Milk vitamin content is highly variable among mammalian species and it is strictly correlated with the vitamin status and the diet administered to the mother. Fat-soluble vitamins content in donkey milk is, on average, lower compared to ruminants' milk, while vitamin C content determined in donkey milk is higher compared to dairy cows' milk, showing a great similarity with human milk. In donkey milk, the content of vitamins of the B-complex such as thiamine, riboflavin, niacin, pyridoxine, and folic acid is higher compared to human milk. The use of donkey milk as a new functional food must be further evaluated in interdisciplinary clinical trials in which pediatricians, dietitians, and food scientists must be involved to deepen the knowledge about the positive health impact of donkey milk in different sensitive people, especially children and the elderly.

Milk Fatty Acid Profiles in Different Animal Species: Focus on the Potential Effect of Selected PUFAs on Metabolism and Brain Functions

Milk contains several important nutrients that are beneficial for human health. This review considers the nutritional qualities of essential fatty acids (FAs), especially omega-3 (ω-3) and omega-6 (ω-6) polyunsaturated fatty acids (PUFAs) present in milk from ruminant and non-ruminant species. In particular, the impact of milk fatty acids on metabolism is discussed, including its effects on the central nervous system. In addition, we presented data indicating how animal feeding-the main way to modify milk fat composition-may have a potential impact on human health, and how rearing and feeding systems strongly affect milk quality within the same animal species. Finally, we have presented the results of in vivo studies aimed at supporting the beneficial effects of milk FA intake in animal models, and the factors limiting their transferability to humans were discussed.

Days in milk alters the milk fatty acid profile of grazing donkeys: A preliminary study

The aim of this study was to characterize and determine how days in milk (DIM) affect the milk fatty acid (FA) profile of grazing donkeys. Donkey milk is very similar to human milk, containing bioactive molecules such as FA and proteins. However, there is a lack of scientific and technical information on the changes in the FA profile of asinine milk in pasture-feeding systems. Seven multiparous Pega donkeys, maintained in an exclusively extensive system, were used. Milking was undertaken twice a day, once a week for 16 weeks. Milk samples were composed according to the average lactating days as follows: 55, 110, 165, 220 and 275 DIM. A descriptive analysis of the milk fat composition was performed, and the linear and quadratic effects of DIM on the milk FA profile were tested. The milk FA profile of grazing donkeys is influenced by lactation days and is characterized by high concentrations of polyunsaturated FA (PUFA) with a low n-6 to n-3 ratio (0.66 g/100 g), mainly due to the high level of linolenic acid (16.8 g/100 g). Most of the individual FAs did not change during lactation, but stearic and oleic acid linearly decreased (p < .05), and total polyunsaturated FA (PUFA) and n-3 FA increased (p < .05) with DIM. The milk profile of grazing donkeys is influenced by the day of lactation and is characterized by a high concentration of n-3 PUFA (mainly α-linolenic acid) and a lower n-6 to n-3 ratio. As the number of days of lactation increased, the concentration of n-3 PUFA also increased. Therefore, higher milk quality may be associated with higher days in milk.

Donkey milk inhibits triple-negative breast tumor progression and is associated with increased cleaved-caspase-3 expression

Donkey milk is considered an ideal substitute for human milk and is considered a potential complementary dairy product for the treatment of a variety of human diseases, including cancer. The purpose of this study was to investigate the inhibitory effect of donkey colostrum (DC) and mature milk (DM) on 4T1 triple-negative breast cancer (TNBC) tumors in mice. Metabolomics analyses showed that a total of 476 possible metabolites were found in both types of milk. Among them, 34 differential metabolites were identified, including 25 up-regulated and 9 down-regulated metabolites in the DC compared with DM. Both DC and DM are rich in many known anticancer constituents. The inhibitory effects of DC and DM on 4T1 primary tumors and the relative organ weight of the liver and lungs were determined by measuring the volume of primary tumors and weighing the liver and lungs. Both DC and DM significantly reduced both the primary tumor size and relative organ weight of the liver and lungs in 4T1 mice without affecting the bodyweight of mice. When the expression of cleaved caspase-3, Bax, and MMP2 was investigated by immunohistochemistry, the results showed that DC and DM inhibited the progression of 4T1 tumors by inducing the expression of cleaved-caspase-3 and Bax, and inhibiting the expression of MMP2 and CD31. Our data suggest that DC and DM inhibit the growth and metastasis of mouse 4T1 tumors by inducing apoptosis.

Plasma lipidome of healthy and Rhodococcus equi-infected foals over time

BACKGROUND

Many foals that develop thoracic ultrasonographic lesions as a result of Rhodococcus equi infection heal on their own. However, most of these foals receive antimicrobials because foals at risk of developing clinical pneumonia cannot be identified. Untargeted lipidomics is useful to identify candidate biomarkers.

OBJECTIVES

(a) To describe the changes that occur in foal lipidomics as a result of ageing (birth to 8 weeks) and (b) To compare these results with those observed in foals after experimental infection with R. equi.

STUDY DESIGN

Experimental study.

METHODS

Healthy newborn foals (n = 9) were challenged with R. equi intratracheally the first week of life. Foals were treated with antimicrobials if they developed clinical pneumonia (n = 4, "clinical group") or were closely monitored if they showed no signs of disease (n = 5 "subclinical group"). An unchallenged group (n = 4) was also included. All foals were free of disease (transtracheal wash fluid evaluation and culture as well as thoracic ultrasonography) by 8 weeks of life. Plasma lipidomics was determined by LC-MS weekly for the study duration (8 weeks).

RESULTS

Both ageing and experimental infection altered the foal's plasma lipidome as demonstrated by multivariate statistical analysis. The intensities of 31 lipids were altered by ageing and 12 by infection (P < .05). Furthermore, nine lipids changed by more than twofold between clinical and subclinical groups.

MAIN LIMITATIONS

The number of foals is limited. Foals were experimentally challenged with R. equi.

CONCLUSIONS

Ageing and R. equi infection induced changes in the plasma lipidome of foals. These experimental results provide the background for future work in the discovery of earlier biomarkers of R. equi pneumonia. Early identification of foals at risk of developing clinical pneumonia is key in order to decrease antimicrobial use and development of antimicrobial resistance.

Detection of maple toxins in mare's milk

Background

Plants from the Sapindaceae family that are consumed by horses (maple) and humans (ackee and litchi) are known to contain the toxins hypoglycin A and methylenecyclopropylglycine which cause seasonally occurring myopathy in horses and entero‐encephalopathic sickness in humans. Vertical transmission of these toxins from a mare to her foal has been described once. However the mare's milk was not available for analysis in this case. We investigated mare's milk in a similar case.

Objective

We hypothesized that hypoglycin A and methylenecyclopropylglycine, like other amino acids' are secreted into the milk.

Animals

Mare with atypical myopathy.

Methods

A sample of the mare's milk and 6 commercial horse milk samples were extracted with a methanolic standard solution and analyzed for hypoglycin A, methylenecyclopropylglycine, and metabolites using tandem mass spectrometry after column chromatographic separation.

Results

There were hypoglycin A (0.4 μg/L) and the associated metabolites methylenecyclopropylacetyl glycine and carnitine (18.5 and 24.6 μg/L) plus increased concentrations of several acylcarnitines in the milk. The milk also contained methylenecyclopropylformyl glycine and carnitine (0.8 and 60 μg/L). The latter substances were also detected in 1 of 6 commercial horse milk samples.

Conclusions and Clinical Importance

Transmission of the maple toxins can occur through mare's milk. Vertical transmission of Sapindacea toxins might also have importance for human medicine, for example, after consumption of ackee or litchi.

The Regenerative Potential of Donkey and Human Milk on the Redox-Sensitive and Proliferative Signaling Pathways of Skin Fibroblasts

The influence of milk bioactive peptides on skin regenerative potential and rejuvenation is very often limited because of allergic reactions. The current study is aimed at exploring the influence of donkey colostrum and mature milk, human colostrum and mature milk, and β-casein and β-casomorphine-7, on the growth and inflammatory response of the culture of cultured skin fibroblasts exposed to these conditions for twenty-four hours. Their effects on the growth-regulatory kinases and redox-sensitive, proinflammatory transcriptional factor NF-κB were detected by using specific primary antibodies against NF-κB p65, Akt-1, phospho-Akt-1, Erk-1, phospho-Erk-1, JNK, phospho-JNK, phospho-STAT-1, and CD26, while logarithmic integrated fluorescence intensity patterns were recorded by flow cytometry. The downregulation of NF-κB p65 was observed after the exposure of skin fibroblasts to donkey milk and human colostrum, while β-casein and β-casomorphine-7 exerted the opposite effect, which suggests that noncasein bioactive peptides of donkey and human milk may be responsible for anti-inflammatory properties. The exposure to all milk species examined and β-casein leads to the activation of growth-regulatory kinases (Akt1/2/3 kinase, Erk kinase, JNK kinase, and Stat-1 kinase), especially for the p-Erk pathway, which suggests that essential amino acids of casein may be responsible for Erk-induced cell cycle activation and proliferation. The opposite effect was observed when cells were exposed to β-casomorphine-7, which may affect the skin fibroblast survival and their proliferative and regenerative potential. Donkey milk did not significantly change the CD26 antigen expression. In conclusion, our results suggest that among cell signaling molecules, the most sensitive but nonspecific downstream effector is p-Erk kinase, which may point to donkey milk usefulness in wound healing, regenerative, and aesthetic dermatology. The noncasein bioactive peptides of donkey milk may be responsible for the anti-inflammatory property of donkey milk and colostrum, which may indicate the usefulness in the treatment of inflammatory skin diseases.

Investigation of donkey milk bacterial diversity by 16S rDNA high-throughput sequencing on a Cyprus donkey farm

The interest in milk originating from donkeys is growing worldwide due to its claimed functional and nutritional properties, especially for sensitive population groups, such as infants with cow milk protein allergy. The current study aimed to assess the microbiological quality of donkey milk produced in a donkey farm in Cyprus using culture-based and high-throughput sequencing techniques. The culture-based microbiological analysis showed very low microbial counts, whereas important food-borne pathogens were not detected in any sample. In addition, high-throughput sequencing was applied to characterize the bacterial communities of donkey milk samples. Donkey milk mostly composed of gram-negative Proteobacteria, including Sphingomonas, Pseudomonas, Mesorhizobium, and Acinetobacter; lactic acid bacteria, including Lactobacillus and Streptococcus; the endospores forming Clostridium; and the environmental genera Flavobacterium and Ralstonia, detected in lower relative abundances. The results of the study support existing findings that donkey milk contains mostly gram-negative bacteria. Moreover, it raises questions regarding the contribution of (1) antimicrobial agents (i.e., lysozyme, peptides) in shaping the microbial communities and (2) bacterial microbiota to the functional value of donkey milk.

Microbial Profile Antibacterial Properties and Chemical Composition of Raw Donkey Milk

The human interest in donkey milk is growing due to its nutritional, functional properties and excellent microbiological quality according to published reports. However, more research needs to be conducted to assess the above variables from various breeds. In the present study, milk samples were collected from 17 Cypriot and six Arcadian healthy Greek donkeys. The microbiological quality, somatic cell counts (SCC), chemical composition analysis, and antimicrobial activity of the samples was assessed. In addition, clustering and identification of the bacterial composition was performed by RAPD-PCR and 16S rDNA sequencing, respectively. The good microbiological quality of the samples as estimated by the total aerobic mesophilic and psychrotrophic counts, which ranged from 2.18 to 2.71 log CFU/mL and from 1.48 to 2.37 log CFU/mL, respectively, was also verified. SCC were below 4.4 log CFU/mL. However, potential pathogenic species of Staphylococcus aureus, Bacillus cereus, and Clostridium spp. were enumerated in the milk of both breeds. The gross chemical composition showed mean values for fat, protein, and lactose from 0.82% to 1.24%, 1.22% to 1.87%, and 6.01% to 6.78%, respectively. All milk samples exhibited an antimicrobial activity against St. haemolyticus and Listeria monocytogenes, although quality control measures should be taken for health and safety prior to human consumption.

Donkey milk composition and its therapeutic applications

Milk contains plentiful nutrients. In Western countries, cow’s milk fat is supposed as a risk factor for health because it is a source of a high fraction of saturated fatty acids. There has been increasing attention in donkey’s milk. Donkeys’ milk is preferential as a potential new dietetic food and a good alternative for infant nutrition in the case of bovine milk protein allergy. The microbiota present in this food may be responsible for its beneficial effects. Considering the potential health benefits, an increase in utilization of donkeys’ milk is expected. The present review addresses various aspects of donkey milk with special emphasis on milk yield, composition, shelf life, antimicrobial, therapeutic and cosmetic properties.

Compared analysis of microbial diversity in donkey milk from Xinjiang and Shandong of China through High-throughput sequencing

Donkey milk has received increasing attention from consumers and dairy industry because of its nutritional value, health benefits, and proximity to human milk. Microbial diversity in donkey milk has a great impact on its quality and safety, however, microbiota in donkey milk from the major donkey-breeding regions of China have not been well documented. In this study, bacterial communities in donkey milk from Yopurga County in Western China (XJ), and Dong'e County in Eastern China (SD) were determined using high-throughput sequencing. Major phyla identified in the two donkey milk groups consistently included Acinetobacter, Proteobacteria, Firmicutes, and Bacteroidetes but with very different abundance for each phylum. Prevelence of genera was found to be diverse between the two groups, with Macrococcus and Acinetobacter dominating in the XJ samples while Streptococcus, Pseudoclavibacter, and Pseudomonas being the most abundant ones in the XJ samples. Alpha diversity analysis showed that there was significant difference in richness between the two sample groups but no difference in bacterial community diversity or coverage. The presence of possible harmful bacteria and lactic acid bacteria in donkey milk in this study provides the microbial profiles of pathogens and spoilage bacteria that need to be controlled and proposes possible utilization of beneficial microbial resources for the future.

Chemical composition and lipid profile of mare colostrum and milk of the quarter horse breed

The objective of this study was to characterize the chemical composition and lipid profile of colostrum and milk of purebred Quarter Horse mares. Thirty-four (34) purebred mares were selected, which were then separated into groups according to age, birth order and lactation stage. Colostrum samples were collected in the first six hours after delivery and milk samples from the 7^th postpartum day, with intervals of 14 days until the end of lactation. The samples were refrigerated and sent to the Milk Laboratory of the University (Laboleite—UFRN), where they were analyzed for chemical composition. Colostrum was assessed by refractometry. The lipid profile was determined by gas chromatography through a separation of methyl esters. The data were tabulated and subjected to descriptive statistics and analysis of variance by the F-Test, and the groups were compared by the Tukey test using a significance level of 5%. There was high protein content and reduced lactose content for the colostrum of the Quarter Horse mares, differing from other breeds. The milk composition was not influenced by the mares’ age. However, variations in the lactation stage and in the birth order of the Quarter Horse mares altered the milk’s chemical composition. There is variation in the lipid composition of milk according to the lactation stage, without changing the characteristic profile of the mares’ milk or diminishing the nutritional quality of the lipid fraction.