Research on donkey milk · Study 67

Yeast in the feed trough: what a yeast polysaccharide changed in milk, blood and gut flora

A team from Liaocheng University gave Dezhou jennies and their foals a supplement of yeast sugar compounds for 23 days and measured milk, blood values, metabolites and gut bacteria.

Important: A feeding trial on animals. It examines the milk, blood and gut flora of donkeys and makes no statement about any effect of donkey milk in humans.

12mother–foal pairs

23trial days

10g supplement per pair/day

Trial procedure · runs automatically

23 days in time-lapse

12 jennies with foals around 45 days old, two groups of 6 pairs each. Same basic ration twice a day; one group additionally received the yeast polysaccharide.

Trial day1

Basic ration of both groups

Layer by layer: what was in the trough

Notable: one premix contained live Bacillus cultures and baker’s yeast (Saccharomyces cerevisiae). So the control group also received yeast, just not the polysaccharide.

Shares according to Table 1; ration with 6.5 % crude protein. The polysaccharide came from a Chinese yeast manufacturer; the paper does not state its composition.

Milk of the jennies · tap a row

Nothing measurable changed in the milk

Control = 100. The bars show the standard error (SEM). No milk value differed significantly.

6080100120140

ControlYeast group

Immune values in the blood · changes automatically

In the jennies’ blood, IgA and IgG rose

Antibodies (IgA, IgG, IgM) and complement factors (C3, C4) in serum, measured on day 23. Logarithmic scale; the paper gives no units. Red = significant (p < 0.05).

Blood values of the animals, not milk values. According to the paper, the immune values in the milk did not differ significantly. The interpretation as “improved immune function” is that of the authors; a benefit was not examined.

Metabolites in the blood · tap a book

388 molecules, sorted onto the shelf by class

Detected in blood serum by mass spectrometry and assigned to chemical classes. Book width = number.

Gut bacteria from faecal samples

Much in common, some things shifted

Bacterial types (OTU) per group; light = in both groups.

jennies

group 1 onlysharedgroup 2 only

Foals

Jennies with supplement

Terrisporobacter ↑Cellulosilyticum ↑Howardella ↑Dorea ↑Saccharimonadaceae ↑Oscillospirales ↓

Diversity (Shannon, Chao, Simpson etc.): no significant difference.

Foals with supplement

15 genera ↑, incl.LactobacillusPrevotellaStreptococcusEscherichia-Shigella

Diversity: Shannon and Ace index higher, Simpson index lower.

16S sequencing. Which of groups 1 and 2 is the yeast group is not clear from the text. What was measured was composition, not the health of the animals.

Critical assessment

Text versus table: our cross-check

AbstractThe supplement is said to have “increased” the foals’ blood glucose and creatinine.

Table 3Both values were lower in the yeast group: 4.1 vs. 5.1 and 94.5 vs. 137.6.

AbstractThe foals’ white blood cells are said to have “tended to decrease”.

Table 3They were significantly higher: 11.2 vs. 8 (p = 0.03).

DiscussionThe supplement is said to have increased milk yield.

Table 2713 vs. 647 – with p = 0.63, no reliable difference; unit not stated.

Results493 changed metabolites.

BreakdownUp- plus down-regulated add up to 74 (jennies) and 38 (foals).

Conclusion0.10 % is said to be the “optimal” dose.

MethodsOnly one dose was tested, given as 10 g per pair per day.

Small & short: 6 pairs per group, 23 days, no adaptation phase described.

Incomplete: no units in Tables 2–4; the fat value of 0.06 is unusually low for donkey milk.

Transparent: public research funding, sequencing raw data deposited (PRJNA1031603), no conflicts of interest declared.

Editorial assessment: For the milk, the result is a null finding – amount and composition remained the same within measurement accuracy. The other findings concern the blood and gut of the animals and should be read with caution because of the small groups and the contradictions in the paper.

Research question for DON DONKEY’S®

What does a feed additive change in the milk – and what not?

Sometimes an additive changes the amount or fat pattern of the milk, sometimes nothing. For us, this means recording additives on the partner farms and reading studies by what they actually measured in the milk itself.

Document additives per farmCompare with Studies 61 and 66Ration & bacterial count: Study 57

Original publication

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

Original title of the publication.

Huang B., Khan M. Z., Chen Y., Liang H., Kou X., Wang X., Ren W., Wang C., Zhang Z.
Frontiers in Microbiology · 2023 · volume 14, article 1289371 · open access
Liaocheng University, China; University of Agriculture Dera Ismail Khan, Pakistan

DOI: 10.3389/fmicb.2023.1289371

Transparency: public funding (China, Shandong Province). According to the publication, no conflicts of interest; the polysaccharide came from a yeast manufacturer. No product-related statement for DON DONKEY’S®.

Summarised and reviewed by the DON DONKEY’S editorial team on the basis of the original publication · as of October 2026

End of the study summary

Note on our products

The study summarised above was carried out independently of DON DONKEY’S® and does not relate to our products. It serves solely to inform about the state of research.

DON DONKEY’S® donkey milk and donkey milk powder are foods. They are not intended to prevent, treat or cure any disease and do not replace medical advice.

From our shop

DON DONKEY’S® donkey milk

100 % donkey milk · raw milk, frozen

On this page we report the findings of a published study. Independently of that, you will find our donkey milk here: 100 % donkey milk, frozen as raw milk.

Transparency: The study examined Dezhou jennies in China – not the animals of our partner farms.

€24,90

100 ml bottle / 100ml · Unit price: €249,00 / 1 l · incl. VAT, plus shipping

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Also in our shop

Donkey Milk Powder

Donkey milk in powder form

For anyone who prefers a longer shelf life: our donkey milk in powder form – easy to store and portion.

Transparency: The study examined fresh donkey milk, not our donkey milk powder.