Summary of alpha diversity measures per dietary Se treatment group¹.

<p>Summary of alpha diversity measures per dietary Se treatment group<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0179215#t002fn001" target="_blank">¹</a>.</p

Principal coordinate analysis (PCoA) of unweighted UniFrac distances of 16S rRNA genes.

<p>Data obtained from nasal samples of randomly chosen healthy control calves (n = 5) and calves fed either medium (n = 6) or high (n = 5) Se-enriched alfalfa hay for 8 weeks. Alfalfa hay was harvested from fields with no Se fertilization (control) or from fields fertilized with sodium-selenate at application rates of 45.0 (medium) or 89.9 (high) g Se/ha.</p

Linear discriminant analysis of KEGG pathways encoded by the nasal microbiota and their associations with dietary Se treatment¹.

<p>Only a LDA score of >2.5 is shown.</p

Relative abundance of the most prevalent bacterial phyla identified in the nasal samples of randomly chosen healthy control calves (n = 5) and calves fed either medium (n = 6) or high (n = 5) Se-enriched alfalfa hay for 8 weeks.

<p>Alfalfa hay was harvested from fields with no Se fertilization (control) or from fields fertilized with sodium-selenate at application rates of 45.0 (medium) or 89.9 (high) g Se/ha.</p

Linear discriminant analysis of bacterial taxa and their associations with dietary Se treatment¹.

<p>Only a LDA score of >3 is shown.</p

Whole-blood Se concentrations (mean ± SEM) for weaned beef calves that were consuming alfalfa hay harvested from fields with no Se fertilization (control; n = 3 pens with 5 calves/pen) or from fields fertilized with sodium-selenate at application rates of 45.0 (medium; n = 3 pens with 5 calves/pen) or 89.9 (high; n = 3 pens with 5 calves/pen) g Se/ha for 8 weeks.

<p>The normal reference interval for WB-Se concentrations of beef cattle is 120 to 300 ng/mL.</p

The effect of Se-source and dosage on sheep requiring oxytetracyline treatment.

<p>Foot rot severity was assessed after 0, 20, 28, 40, and 60 wk of Se supplementation in ewes receiving no Se treatment, Na-selenate at a dosage rate of 8.95 mg Se/wk per ewe, or Na-selenite and Se-Yeast at 4.9, 14.7, or 24.5 mg Se/wk per ewe for 62 wk. If a sheep had one foot with a score of 4, or one foot with a score of 3 and a second foot with a score of 2 or greater, or if all 4 feet had FR, then 20 mg/kg oxytetracycline was administered subcutaneously (Liquamycin LA-200; Pfizer Animal Health, Exton, PA) at the 28- and 40-wk foot trimming sessions. No significant differences in parental oxytetracycline treatment were observed for individual treatment groups at 28 wk; however; more ewes with supranutritional Na-selenite treatment were treated with oxytetracyline than ewes receiving the lowest Na-selenite dosage (<i>P</i> = 0.05). At 40 wk, more ewes receiving Na-selenite at the highest dosage had to be treated with oxytetracycline than ewes receiving no Se, Na-selenite at both lower dosages, or Se-yeast at 14.5 mg/wk (all <i>P</i> ≤ 0.05).</p

The effect of Se-source on ex vivo neutrophil bacterial killing in sheep.

<p>Ex vivo neutrophil bacterial killing was assessed after 60 wk of Se supplementation in healthy and footrot (FR)-affected ewes receiving no Se treatment, Na-selenate, Na-selenite, and Se-Yeast for 62 wk<b>. </b><b>A</b>) Weekly oral Se drenching improved neutrophil bacterial killing in FR-affected ewes to percentages that were similar to healthy supplemented or healthy non-supplemented ewes. <b>B</b>) In FR-affected ewes, Na-selenate, Na-selenite, or Se-yeast improved neutrophil bacterial killing compared with no Se supplementation. The effect tended to be greater in ewes receiving Se-yeast compared with Na-selenite. The three dosages of Na-selenite or Se-yeast were combined because they did not differ. Different superscripts indicate group differences at <i>P</i> ≤ 0.10.</p

The effect of Se-source and dosage on antibody titers to keyhole limpet hemocyanin (KLH).

<p>Antibody titers to keyhole limpet hemocyanin (KLH) were assessed after 60 wk of Se supplementation in healthy and footrot (FR)-affected sheep receiving no Se treatment, Na-selenate at a dosage rate of 8.95 mg Se/wk per ewe, or Na-selenite and Se-Yeast at 4.9, 14.7, or 24.5 mg Se/wk per ewe for 62 wk. A) Weekly oral Se drenching improved KLH antibody titers in FR-affected ewes to titers that were similar to healthy ewes receiving no Se or healthy ewes receiving Se treatment. <b>B</b>) In FR-affected ewes, KLH antibody titers were greater in all Se-supplemented groups compared with the non supplemented group with the exception of the 24.5 mg/wk Na-selenite group. Different superscripts indicate group differences at <i>P</i> ≤ 0.10.</p

The effect of Se-source, Se-dosage, and foot rot status on serum-Se concentrations in sheep.

<p>Serum-Se concentrations were measured after 0, 14, 27, 40, and 54 wk of Se supplementation, and foot rot severity was assessed after 0, 20, 28, 40, and 60 wk of Se supplementation in ewes receiving no Se treatment, Na-selenate at a dosage rate of 8.95 mg Se/wk per ewe, or Na-selenite and Se-Yeast at 4.9, 14.7, or 24.5 mg Se/wk per ewe for 62 wk. Serum-Se concentrations for each treatment group are shown as separate bars for healthy sheep (lighter background) and for sheep with foot rot (darker background). At baseline (wk 0), no significant treatment group differences were observed; however, healthy ewes had higher serum-Se concentrations than ewes with FR (<i>P</i> = 0.01). After treatments started, group differences by foot-rot status subsided, whereas Se-source and Se-dosage affected serum-Se concentrations. Both healthy and FR-affected ewes that received no Se treatment had decreased serum-Se concentrations (<i>P</i> < 0.0001). Supranutritional Se-yeast supplementation increased serum-Se concentrations linearly with dosage (<i>P</i> < 0.0001), whereas ewes receiving supranutritional Na-selenite supplementation at 14.7 and 24.5 mg Se/wk achieved similar serum-Se concentrations as ewes receiving 4.9 mg/wk of Se-yeast.</p