This study aimed to investigate the effects of compound probiotics (consisting of 10⁸ cfu/g of Lactobacillus plantarum, 10⁸ cfu/g of Pediococcus acidilactici, 10⁸ cfu/g of Pediococcus pentosaceus, 10⁷ cfu/g of and Bacillus subtilis) on growth performance, rumen fermentation, bacteria community, blood parameters, and health status of Holstein calves at the first 3 mo of age. Forty-eight newborn calves were randomly divided into the following 3 groups: control group (milk replacer with no compound probiotics), low compound probiotics group (milk replacer + 0.12 g of compound probiotics per head per day), and high compound probiotics group (HP; milk replacer + 1.2 g of compound probiotics per head per day). Starter pellets of the low compound probiotics and HP groups were coated with 0.05% compound probiotics. Milk replacer was provided from 2 to 63 d of age (6 L at 2-10 d, 8 L at 11-42 d, 6 L at 43-49 d, 4 L at 50-56 d, and 2 L at 57-63 d), and starter pellets were provided ad libitum from 7 to 90 d of age. Body weight and body size (d 1, 30, 60, and 90), blood (d 40 and 80), and rumen fluid (d 90) were analyzed using the one-way ANOVA procedure; fecal score was recorded daily and analyzed as repeated measures using the mixed model procedure. Results showed that diet supplemented with compound probiotics had no effects on the body weight, average daily gain, dry matter intake, and feed efficiency. At 90 d of age, diet supplemented with compound probiotics decreased the withers height. Immunity activities increased in the HP group, supported by the increased concentrations of serum total protein and immunoglobulins at 40 d of age, and by the increased activity of superoxide dismutase at 80 d of age. Diet supplemented with compound probiotics altered rumen fermentation, indicated by the decreased rumen acetic acid and propionic acid, and the increased butyric acid concentrations. Diet supplemented with compound probiotics improved the health status of calves, indicated by the decreased fecal score at 3 wk of age and the decreased medicine treatments. In summary, although diet supplemented with HP decreased the withers height, this level of probiotics is recommended to improve rumen development and health status of newborn Holstein calves.

Asparagine (Asn), an activator of ornithine decarboxylase (ODC), stimulates cell proliferation in intestinal epithelial cells. We hypothesized that Asn can mitigate LPS-induced injury of intestinal structure and barrier function by regulating inflammatory signaling pathways. We executed the following experiment using weanling pigs for each of the groups: (1) non-challenged control; (2) LPS-challenged control; (3) LPS + 0.5% Asn; (4) LPS + 1.0% Asn. After 21-d feeding, pigs received an i.p. injection of either saline or LPS. Four h after injection, the mid-jejunum and mid-ileum samples were collected. We found that Asn restored ODC expression that was decreased by LPS treatment. Asn also restored intestinal morphology and barrier function that were impaired by LPS treatment. In addition, Asn down-regulated intestinal caspase-3 protein expression and TNF-α concentration, and decreased the mRNA expression of intestinal TLR4, TLR4 downstream signals (myeloid differentiation factor 88, IL-1 receptor-associated kinase 1 and TNF-α receptor-associated factor 6 and NOD1, NOD2 and their adaptor molecule (receptor-interacting serine/threonine-protein kinase 2). Moreover, Asn decreased p38 phosphorylation but increased ERK1/2 phosphorylation. Our results suggest that Asn improves intestinal integrity during an inflammatory insult, which appears to be related to the decrease of intestinal pro-inflammatory cytokine (via TLR4, NODs and p38) and of enterocyte apoptosis (via p38 and ERK1/2).