Effects of <i>Kluyveromyces marxianus</i> on the relative mRNA expression of ileal genes¹ of broilers (21 d of age).

<p>Effects of <i>Kluyveromyces marxianus</i> on the relative mRNA expression of ileal genes<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0180884#t007fn002" target="_blank">¹</a> of broilers (21 d of age).</p

Effects of <i>Kluyveromyces marxianus</i> on intestinal biochemical indicies¹ of broilers (21 d of age).

<p>Effects of <i>Kluyveromyces marxianus</i> on intestinal biochemical indicies<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0180884#t005fn002" target="_blank">¹</a> of broilers (21 d of age).</p

Effects of <i>Kluyveromyces marxianus</i> on the relative abundance of main taxa (top ten) in the ileum at different taxonomic levels of broilers (<i>n</i> 8).

<p>C, control group; L, low-dose (0.5 g/kg) group with <i>K</i>. <i>marxianus</i>; M, medium-dose (1.5 g/kg) group with <i>K</i>. <i>marxianus</i>; H, high-dose (2.5 g/kg) group with <i>K</i>. <i>marxianus</i>.</p

Venn graph for ileal microbiota of broilers at 21 d of age (<i>n</i> 8).

<p>Each circle represents a group of samples. The numbers of common bacterial operational taxonomic units (OTUs) are displayed in the overlapping section between different circles, while the numbers in the non-overlapping section between different circles represent the number of their respectively unique OTUs. C, control group; L, low-dose (0.5 g/kg) group with <i>K</i>. <i>marxianus</i>; M, medium-dose (1.5 g/kg) group with <i>K</i>. <i>marxianus</i>; H, high-dose (2.5 g/kg) group with <i>K</i>. <i>marxianus</i>.</p

Effects of <i>Kluyveromyces marxianus</i> on the relative weight¹ of immune organs and serum parameters of broilers (21 d of age).

<p>Effects of <i>Kluyveromyces marxianus</i> on the relative weight<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0180884#t004fn002" target="_blank">¹</a> of immune organs and serum parameters of broilers (21 d of age).</p

Similarity analysis of ileal microbiota between the control and <i>Kluyveromyces marxianus</i>-treated birds (<i>n</i> 8).

<p>a. Clustering analysis: the left is UPGMA (unweighted pair-group method with arithmetic mean) clustering tree structure, while the relative abundance of main taxa at phylum taxonomic level is displayed on the right. b. PCA: abscissa represents the first principal component, ordinate represents the second principal component, and the percentage represents the contribution of the principal component to the sample difference. C, control group; L, low-dose (0.5 g/kg) group with <i>K</i>. <i>marxianus</i>; M, medium-dose (1.5 g/kg) group with <i>K</i>. <i>marxianus</i>; H, high-dose (2.5 g/kg) group with <i>K</i>. <i>marxianus</i>.</p

Composition and nutrient levels of diets (g/kg).

<p>Composition and nutrient levels of diets (g/kg).</p

Primers used in the real-time PCR.

<p>Primers used in the real-time PCR.</p

Effects of <i>Kluyveromyces marxianus</i> on growth performance¹ of broilers.

<p>Effects of <i>Kluyveromyces marxianus</i> on growth performance<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0180884#t003fn002" target="_blank">¹</a> of broilers.</p

Effects of <i>Kluyveromyces marxianus</i> supplementation on immune responses, intestinal structure and microbiota in broiler chickens

<div><p>To investigate the effects of <i>Kluyveromyces marxianus</i> on immune responses, intestinal structure and microbiota in broilers, 840 1-d-old broiler chicks were randomly divided into seven groups (eight replicates) and were fed basal diets without or with 0.25, 0.50, 1.0, 1.5, 2.0, and 2.5 g/kg of <i>K</i>. <i>marxianus</i> (2.0×10¹⁰ CFU/g). Serum and intestine samples were collected at 21 d of age. The results showed that increasing <i>K</i>. <i>marxianus</i> addition linearly reduced feed conversion ratio but linearly elevated relative thymus weight, as well as quadratically increased serum lysozyme and IgG levels, with the medium dose (1.0 g/kg) being the most effective. The ratio of villus height to crypt depth of jejunum and ileum, ileal villus height and sucrase activity, as well as the mRNA expression of ileal mucin-2, claudin-1 and sodium glucose cotransporter 1 linearly responded to the increasing <i>K</i>. <i>marxianus</i> addition. Supplemental <i>K</i>. <i>marxianus</i> at low (0.5 g/kg), medium (1.5 g/kg) and high (2.5 g/kg) dose all decreased the abundance of phylum <i>Cyanobacteria</i>, increased the abundance of phylum <i>Firmicutes</i> and genus <i>Lactobacillus</i> in ileum. The high dose of <i>K</i>. <i>marxianus</i> addition also reduced the abundance of order <i>Rickettsiales</i> and <i>Pseudomonadales</i> along with species <i>Acinetobacter junii</i>. Ileal bacterial communities between <i>K</i>. <i>marxianus</i>-treated and untreated groups formed distinctly different clusters. In summary, <i>K</i>. <i>marxianus</i> supplementation benefits feed efficiency and immune function, as well as intestinal structure in broilers, which might be attributed to the improved ileal microbial structure. Supplemental <i>K</i>. <i>marxianus</i> at high dose (2.5 g/kg) was more effective for feed efficiency and intestinal health of broilers, while the innate immunity was optimized at a medium dose (1.0 g/kg).</p></div