{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:31:01Z","timestamp":1787027461836,"version":"build-2736575974"},"reference-count":40,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2024,10,19]],"date-time":"2024-10-19T00:00:00Z","timestamp":1729296000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Shandong Provincial Natural Science Foundation","award":["ZR2023MC149"],"award-info":[{"award-number":["ZR2023MC149"]}]},{"name":"Shandong Provincial Natural Science Foundation","award":["2022YFD1600103"],"award-info":[{"award-number":["2022YFD1600103"]}]},{"name":"Shandong Provincial Natural Science Foundation","award":["2021TZXD012"],"award-info":[{"award-number":["2021TZXD012"]}]},{"name":"Shandong Provincial Natural Science Foundation","award":["319312105-5"],"award-info":[{"award-number":["319312105-5"]}]},{"name":"National Key R &amp; D Program of China","award":["ZR2023MC149"],"award-info":[{"award-number":["ZR2023MC149"]}]},{"name":"National Key R &amp; D Program of China","award":["2022YFD1600103"],"award-info":[{"award-number":["2022YFD1600103"]}]},{"name":"National Key R &amp; D Program of China","award":["2021TZXD012"],"award-info":[{"award-number":["2021TZXD012"]}]},{"name":"National Key R &amp; D Program of China","award":["319312105-5"],"award-info":[{"award-number":["319312105-5"]}]},{"name":"Key Technology Research and Development Program of Shandong","award":["ZR2023MC149"],"award-info":[{"award-number":["ZR2023MC149"]}]},{"name":"Key Technology Research and Development Program of Shandong","award":["2022YFD1600103"],"award-info":[{"award-number":["2022YFD1600103"]}]},{"name":"Key Technology Research and Development Program of Shandong","award":["2021TZXD012"],"award-info":[{"award-number":["2021TZXD012"]}]},{"name":"Key Technology Research and Development Program of Shandong","award":["319312105-5"],"award-info":[{"award-number":["319312105-5"]}]},{"name":"Open Project of Liaocheng University Animal Husbandry Discipline","award":["ZR2023MC149"],"award-info":[{"award-number":["ZR2023MC149"]}]},{"name":"Open Project of Liaocheng University Animal Husbandry Discipline","award":["2022YFD1600103"],"award-info":[{"award-number":["2022YFD1600103"]}]},{"name":"Open Project of Liaocheng University Animal Husbandry Discipline","award":["2021TZXD012"],"award-info":[{"award-number":["2021TZXD012"]}]},{"name":"Open Project of Liaocheng University Animal Husbandry Discipline","award":["319312105-5"],"award-info":[{"award-number":["319312105-5"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>This study investigated the effects of adding methionine (Met) in milk production and the milk and blood metabolites of lactating donkeys. Eighteen healthy multiparous donkeys in early-stage lactation were selected for this study. The donkeys were randomly divided into three groups and fed diets with different levels of Met: control group (C, Met 0 g\/d), Met group I (M1, Met 5 g\/d), and Met group II (M2, Met 15 g\/d). The total duration of the experiment was 5 weeks. Donkey milk and blood samples were collected at the end of the experiment. The milk yield and composition, milk, and serum metabolites were analyzed. The results showed that the addition of 5 g of Met significantly increased milk yield as well as the milk composition contents of protein, fat, lactoferrin, polyunsaturated fatty acid (PFA), solids, and solids-not-fat (SNF) (p &lt; 0.05). Significant differences in metabolites were detected among the different samples of milk (p &lt; 0.05). The addition of Met increased the levels of milk metabolites, such as myristic acid, d-glutamine, l-aspartic acid, and LPS 16:0. A total of 753 metabolites were detected in the serum, including 17 differential metabolites between C and M1 and 48 differential metabolites between C and M2. The levels of serum metabolites, such as l-ascorbate, inositol, and l-lysine, were up-regulated by the addition of Met (p &lt; 0.05). The above results indicated that Met increased donkey milk production and milk composition yield and improved milk metabolites by regulating serum metabolites. These results provide a foundation for improving the nutritional needs of lactating donkeys and the nutritional regulation of donkey milk synthesis.<\/jats:p>","DOI":"10.3390\/ani14203027","type":"journal-article","created":{"date-parts":[[2024,10,21]],"date-time":"2024-10-21T08:53:11Z","timestamp":1729500791000},"page":"3027","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Effects of Methionine on Milk Performance and Milk Constituents of Lactating Donkeys"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-7949-1897","authenticated-orcid":false,"given":"Fei","family":"Huang","sequence":"first","affiliation":[{"name":"College of Agriculture and Biology, Liaocheng Research Institute of Donkey High-Efficiency Breeding and Ecological Feeding, Liaocheng University, Liaocheng 252000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-4604-1092","authenticated-orcid":false,"given":"Xinyi","family":"Du","sequence":"additional","affiliation":[{"name":"College of Agriculture and Biology, Liaocheng Research Institute of Donkey High-Efficiency Breeding and Ecological Feeding, Liaocheng University, Liaocheng 252000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-6569-8373","authenticated-orcid":false,"given":"Zongjie","family":"Ma","sequence":"additional","affiliation":[{"name":"College of Agriculture and Biology, Liaocheng Research Institute of Donkey High-Efficiency Breeding and Ecological Feeding, Liaocheng University, Liaocheng 252000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6230-9885","authenticated-orcid":false,"given":"Guiqin","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Agriculture and Biology, Liaocheng Research Institute of Donkey High-Efficiency Breeding and Ecological Feeding, Liaocheng University, Liaocheng 252000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Changfa","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Agriculture and Biology, Liaocheng Research Institute of Donkey High-Efficiency Breeding and Ecological Feeding, Liaocheng University, Liaocheng 252000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8459-1324","authenticated-orcid":false,"given":"Miaomiao","family":"Zhou","sequence":"additional","affiliation":[{"name":"College of Agriculture and Biology, Liaocheng Research Institute of Donkey High-Efficiency Breeding and Ecological Feeding, Liaocheng University, Liaocheng 252000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,10,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Renu, G., Arun, B., Karnam, S., Rahul, M., Yash, P., Varij, N., Mir Asif, I., Sarika, J., and Harish, K. (2023). Milk from Halari Donkey Breed: Nutritional Analysis, Vitamins, Minerals, and Amino Acids Profiling. Foods, 12.","DOI":"10.3390\/foods12040853"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Vincenzo, L., Aristide, M., Angela, S., Salvatore, C., Pasquale De, P., Domenico, R., Giuseppina, P., and Gianluca, N. (2021). Evaluation of Different Test-Day Milk Recording Protocols by Wood\u2019s Model Application for the Estimation of Dairy Goat Milk and Milk Constituent Yield. Animals, 11.","DOI":"10.3390\/ani11041058"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"8741","DOI":"10.3168\/jds.2020-18251","article-title":"Distribution of calcium, phosphorus, sulfur, magnesium, potassium, and sodium in major fractions of donkey milk","volume":"103","author":"Fantuz","year":"2020","journal-title":"J. Dairy Science"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"113113","DOI":"10.1016\/j.lwt.2022.113113","article-title":"Characterization and comparison of whey proteomes from bovine and donkey colostrum and mature milk","volume":"158","author":"Li","year":"2022","journal-title":"Lebensm.-Wiss. Technol."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Vincenzetti, S., Santini, G., Polzonetti, V., Pucciarelli, S., Klimanova, Y., and Polidori, P. (2021). Vitamins in Human and Donkey Milk: Functional and Nutritional Role. Nutrients, 13.","DOI":"10.3390\/nu13051509"},{"key":"ref_6","first-page":"e91","article-title":"Caries in children with lactose intolerance and cow\u2019s milk protein allergy","volume":"32","author":"Suzely","year":"2018","journal-title":"Braz. Oral Res."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"416","DOI":"10.1016\/j.foodres.2018.04.051","article-title":"Donkey milk as a supplement in infant formula: Benefits and technological challenges","volume":"109","author":"Souroullas","year":"2018","journal-title":"Food Res. Int."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"641","DOI":"10.1067\/mpd.2000.104774","article-title":"Role of food protein intolerance in infants with persistent distress attributed to reflux esophagitis","volume":"136","author":"David","year":"2000","journal-title":"J. Pediatr."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Cresi, F., Maggiora, E., Pirra, A., Tonetto, P., Rubino, C., Cavallarin, L., Giribaldi, M., Moro, G.E., Peila, C., and Coscia, A. (2020). Effects on Gastroesophageal Reflux of Donkey Milk-Derived Human Milk Fortifier Versus Standard Fortifier in Preterm Newborns: Additional Data from the FortiLat Study. Nutrients, 12.","DOI":"10.21203\/rs.3.rs-19809\/v1"},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Silvia, V., Stefania, P., Giuseppe, S., Yulia, K., Valeria, P., and Paolo, P. (2020). B-Vitamins Determination in Donkey Milk. Beverages, 6.","DOI":"10.3390\/beverages6030046"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"114805","DOI":"10.1016\/j.lwt.2023.114805","article-title":"Comparative metabolomics analysis of Halari donkey colostrum and mature milk throughout lactation stages using 1H Nuclear Magnetic Resonance","volume":"182","author":"Renu","year":"2023","journal-title":"Lebensm.-Wiss. Technol."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Yue, Y., Li, L., Tong, M., Li, S., Zhao, Y., Guo, X., Guo, Y., Shi, B., and Yan, S. (2022). Effect of Varying Dietary Crude Protein Level on Milk Production, Nutrient Digestibility, and Serum Metabolites by Lactating Donkeys. Animals, 12.","DOI":"10.3390\/ani12162066"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"104971","DOI":"10.1016\/j.jfca.2022.104971","article-title":"Donkey milk composition is altered by lactation stage and jennies age","volume":"115","year":"2023","journal-title":"J. Food Compos. Anal."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Ante, I., Gordan, \u0160., Giovanni, B., Edmondo, \u0160., Nicol\u00f2, A., Jasna, A., Nikolina Kelava, U., Lana, P., Mateja, P., and Miljenko, K. (2023). Potential of Endangered Local Donkey Breeds in Meat and Milk Production. Animals, 13.","DOI":"10.3390\/ani13132146"},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Mohsen Danesh, M., Hassan, K., Rieke, J., Sadjad Danesh, M., Aghil, G., and Amir Mansour, V. (2022). Rumen-protected zinc\u2013methionine dietary inclusion alters dairy cow performances, and oxidative and inflammatory status under long-term environmental heat stress. Front. Vet. Sci., 9.","DOI":"10.3389\/fvets.2022.935939"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Toledo, M.Z., Baez, G.M., Garcia-Guerra, A., Lobos, N.E., Guenther, J.N., Trevisol, E., Luchini, D., Shaver, R.D., and Wiltbank, M.C. (2017). Effect of feeding rumen-protected methionine on productive and reproductive performance of dairy cows. PLoS ONE, 12.","DOI":"10.1371\/journal.pone.0189117"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"367","DOI":"10.55730\/1300-0128.4206","article-title":"Effects of rumen-protected methionine and lysine on milk yield and milk composition inHolstein dairy cows consuming a corn grain and canola meal-based diet","volume":"46","author":"Emrah","year":"2022","journal-title":"Turk. J. Vet. Anim. Sci."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"7085","DOI":"10.3168\/jds.2014-8220","article-title":"Meta-analysis of lactation performance in dairy cows receiving supplemental dietary methionine sources or postruminal infusion of methionine","volume":"97","author":"Zanton","year":"2014","journal-title":"J. Dairy Sci."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"5182","DOI":"10.3168\/jds.2018-15716","article-title":"Effect of N-acetyl-l-methionine supplementation on lactation performance and plasma variables in mid-lactating dairy cows","volume":"102","author":"Liang","year":"2019","journal-title":"J. Dairy Sci."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Wang, J., Zhang, C., Zhao, Q., Li, C., Jin, S., and Gu, X. (2020). Metabolic Profiling of Plasma in Different Calving Body Condition Score Cows Using an Untargeted Liquid Chromatography-Mass Spectrometry Metabolomics Approach. Animals, 10.","DOI":"10.3390\/ani10091709"},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Heischmann, S., Quinn, K., Cruickshank-Quinn, C., Liang, L.P., Reisdorph, R., Reisdorph, N., and Patel, M. (2016). Exploratory Metabolomics Profiling in the Kainic Acid Rat Model Reveals Depletion of 25-Hydroxyvitamin D3 during Epileptogenesis. Sci. Rep., 6.","DOI":"10.1038\/srep31424"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"829","DOI":"10.1242\/bio.017863","article-title":"Metabolomics reveals significant variations in metabolites and correlations regarding the maturation of walnuts (Juglans regia L.)","volume":"5","author":"Rao","year":"2016","journal-title":"Biol. Open"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"115557","DOI":"10.1016\/j.anifeedsci.2022.115557","article-title":"Multiple essential amino acids regulate mammary metabolism and milk protein synthesis in lactating dairy cows","volume":"296","author":"Zhang","year":"2023","journal-title":"Anim. Feed. Sci. Technol."},{"key":"ref_24","first-page":"1339","article-title":"Supplementation of Methionine Dipeptide Enhances the Milking Performance of Lactating Dairy Cows","volume":"14","author":"Wen","year":"2023","journal-title":"Animals"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"115444","DOI":"10.1016\/j.anifeedsci.2022.115444","article-title":"Effects of dietary concentrate to forage ratio on milk performance, milk amino acid composition and milk protein synthesis of lactating donkeys","volume":"292","author":"Liang","year":"2022","journal-title":"Anim. Feed. Sci. Technol."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Wei, C., He, T., Wan, X., Liu, S., Dong, Y., and Qu, Y. (2022). Meta-Analysis of Rumen-Protected Methionine in Milk Production and Composition of Dairy Cows. Animals, 12.","DOI":"10.3390\/ani12121505"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"114494","DOI":"10.1016\/j.anifeedsci.2020.114494","article-title":"Impacts of substitution of canola meal with soybean meal, with and without ruminally protected methionine, on production, reproduction and health of early lactation multiparous Holstein cows through 160 days in milk","volume":"264","author":"Swanepoel","year":"2020","journal-title":"Anim. Feed. Sci. Technol."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Valdir, C., Fernanda, L., Schwab, C.G., Mateus, Z.T., and Edgar Alain, C.-S. (2020). Effects of rumen-protected methionine supplementation on the performance of high production dairy cows in the tropics. PLoS ONE, 16.","DOI":"10.1371\/journal.pone.0243953"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"775","DOI":"10.2527\/jam2016-1594","article-title":"Comparative effects of multiple sources of rumen-protected methionine on milk production and serum amino acid levels in midlactation dairy cows","volume":"94","author":"Zhang","year":"2016","journal-title":"J. Anim. Sci."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"624","DOI":"10.1080\/1828051X.2022.2048973","article-title":"Effect of supplemental rumen-protected methionine on reproduction and production of Awassi ewes","volume":"21","author":"Titi","year":"2022","journal-title":"Ital. J. Anim. Sci."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"110682","DOI":"10.1016\/j.foodres.2021.110682","article-title":"Multi-omics revealed the effects of rumen-protected methionine on the nutrient profile of milk in dairy cows","volume":"149","author":"Gu","year":"2021","journal-title":"Food Res. Int."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"460","DOI":"10.1203\/00006450-200110000-00007","article-title":"A Novel Inhibitor of \u03b2-Glucuronidase: L-Aspartic Acid","volume":"50","author":"Bill","year":"2001","journal-title":"Pediatr. Res."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Livia Simon, S., Miaomiao, Z., G\u00e9za, M., R\u00e9ka, A.V., Oksana, M., Eszter, B., and Sandor, G.V. (2022). Fatty Acid Composition of Milk from Mothers with Normal Weight, Obesity, or Gestational Diabetes. Life, 12.","DOI":"10.3390\/life12071093"},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Navid, G., Nasri, M.H.F., Seyyed Homayoun, F., Seyyed Ehsan, G., and Einar, V.B.P. (2021). Regulation of Nutritional Metabolism in Transition Dairy Goats: Energy Balance, Liver Activity, and Insulin Resistance in Response to Berberine Supplementation. Animals, 11.","DOI":"10.3390\/ani11082236"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"810","DOI":"10.1017\/S1751731114003048","article-title":"Effect of extruded linseeds alone or in combination with fish oil on intake, milk production, plasma metabolite concentrations and milk fatty acid composition in lactating goats","volume":"9","author":"Bernard","year":"2015","journal-title":"Animal"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"283","DOI":"10.21608\/ejnf.2019.79405","article-title":"Effect of Linseed oil Beads Addition with Vitamin E on Performance, Blood Metabolites and milk yield of lactating goats","volume":"22","author":"Abeer","year":"2019","journal-title":"Egypt. J. Nutr. Feed."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"115758","DOI":"10.1016\/j.anifeedsci.2023.115758","article-title":"Feeding rumen-protected Capsicum oleoresin to dairy cows during the transition period and early lactation: Effects on nutrient digestibility, blood metabolites, and performance","volume":"305","author":"Takiya","year":"2023","journal-title":"Anim. Feed. Sci. Technol."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"4629","DOI":"10.3168\/jds.2014-8711","article-title":"Effect of feeding calcareous marine algae to Holstein cows prepartum or postpartum on serum metabolites and performance","volume":"98","author":"Wu","year":"2015","journal-title":"J. Dairy Sci."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"11386","DOI":"10.3168\/jds.2020-18542","article-title":"Feeding rumen-protected lysine prepartum increases energy-corrected milk and milk component yields in Holstein cows during early lactation","volume":"103","author":"Fehlberg","year":"2020","journal-title":"J. Dairy Sci."},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Li, W., Qiu, L., Guan, J., Sun, Y., Zhao, J., and Du, M. (2022). Comparative transcriptome analysis of longissimus dorsi tissues with different intramuscular fat contents from Guangling donkeys. BMC Genom., 23.","DOI":"10.1186\/s12864-022-08857-2"}],"container-title":["Animals"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-2615\/14\/20\/3027\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T16:16:41Z","timestamp":1760113001000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-2615\/14\/20\/3027"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,10,19]]},"references-count":40,"journal-issue":{"issue":"20","published-online":{"date-parts":[[2024,10]]}},"alternative-id":["ani14203027"],"URL":"https:\/\/doi.org\/10.3390\/ani14203027","relation":{},"ISSN":["2076-2615"],"issn-type":[{"value":"2076-2615","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,10,19]]}}}