The objective of this experiment was to investigate the effect of lactic acid bacteria (LAB) and cellulase (CE) on the fermentation quality, rumen degradation rate and bacterial community of mixed silage of soybean residue (SR) and corn stover (CS). The experiment adopted a single-factor experimental design. Four treatment groups were set up: the control group (CON), lactic acid bacteria treatment group (LAB), cellulase treatment group (CE) and lactic acid bacteria + cellulase treatment group (LAB + CE). Among them, the amount of added LAB was 1 × 106 CFU/g, and the amount of added CE was 100 U/g. After 56 days of mixed silage, samples were taken and analyzed, and the chemical composition, fermentation quality, rumen degradation rate and microbial diversity were determined. The results showed that the pH of each treatment group was significantly (p < 0.05) lower than that of CON, while the lactic acid and ammoniacal nitrogen contents of each treatment group were significantly higher than that of CON, with the highest contents in the LAB + CE group. The contents of DNFom (Ash-free NDF), ADFom (Ash-free ADF) and DM in the LAB + CE group were significantly lower than those in the CON group, while the content of crude protein (CP) was significantly higher than that in the CON group. The in situ effective degradation rates of DM (ISDMD), DNF (ISNDFD) and CP (ISCPD) were all significantly (p < 0.05) higher in each treatment group than in the control group. The results of principal component analysis showed that the bacterial composition of the LAB, CE and LAB + CE groups was significantly different from that of the CON group (p < 0.05). Bacterial genus level analysis showed that the content of lactic acid bacteria was significantly higher in the LAB + CE group than in the other treatment groups (p < 0.05), while the content of undesirable bacteria was significantly lower than in the other treatment groups. The results showed that the addition of Lactobacillus and/or cellulase in mixed silage of SR and CS could effectively improve the quality of mixed silage fermentation, rumen degradation rate and microbial diversity, with better results when Lactobacillus and cellulase were added together, which provides new ideas for better application of SR and CS in dairy production.

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In China, the use of antibiotics growth promoters as feed additives has been banned. The goal of raising dairy heifers is to gain a relatively high body weight on a high-fiber diet at first mating or calving, thus increasing economic benefits. The objective of this experiment was to explore the effects of supplemental Clostridium butyricum (C. butyricum) on growth performance, rumen fermentation and microbiota, and blood parameters in Holstein heifers. Twenty Holstein heifers [mean ± standard deviation (SD); age = 182 ± 4.20 d, body weight = 197.53 ± 5.94 kg, dry matter intake (DMI) = 6.10 ± 0.38 kg] were randomly assigned to one of two diets group for a 42-day feeding period: (1) basal diet (an untreated control group, i.e., the CON group) or (2) basal diet plus daily 2 × 108 (colony-forming unit, CFU) of C. butyricum per kg of DMI per heifer (the CB group). The results demonstrated that C. butyricum supplementation increased the average daily gain from d 21 to 42 and DMI compared to the control group. Supplementation with C. butyricum significantly decreased the molar proportion of acetate and the acetate to propionate ratio but increased the molar proportion of butyrate and propionate. Compared with the control group, the relative abundance of Butyrivibrio fibrisolvens, Ruminococcus albus, Ruminobacter amylophilus, Ruminococcus flavefaciens, and Streptococcus bovis increased during the trial period in the CB group. However, C. butyricum had no significant effect on the blood parameters in Holstein heifers. In conclusion, these results show that feeding C. butyricum can improve growth performance and rumen fermentation without any negative impact on blood parameters in Holstein heifers.

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Background As a major disease affecting dairy cow production worldwide, bovine mastitis is caused by a variety of pathogenic microorganisms that eventually cause mammary gland inflammation. Acremonium terricola culture (ATC) is a new type of affordable feed additive produced by the solid fermentation of A. terricola isolated from Cordyceps gunnii and exerted its anti-inflammatory effect. Objectives To evaluate the protective effects of ATC on mastitis and investigate its active mechanism, a lipopolysaccharide (LPS)-induced rat mastitis model was used in two experiments. Design In Experiment 1, a total of 40 female Sprague–Dawley rats were used to determine the optimal supplementary dose of ATC via gavage trial. In Experiment 2, we examined the effects of an optimal dose of ATC on LPS-induced mastitis in rats. Results The results of Experiment 1 showed that administration of ATC improved growth performance and antioxidant functions in the serum and the liver, as well as immunoglobulin A, G, and M levels in rat serum, and it decreased the content of alanine aminotransferase, aspartate aminotransferase, triglyceride, cholesterol, low-density lipoprotein, and serum urea nitrogen in rat serum; a dosage of 250–1,250 mg/kg/day was shown to be high enough to be effective. The results of Experiment 2 indicated that ATC can relieve the inflammatory reaction of mammary glands in rats, and the LPS-induced expression of tumor necrosis factor-α, interleukin-1β, interleukin-6, and inducible nitric oxide synthase significantly decreased after ATC treatment. Moreover, our results demonstrated that ATC markedly enhanced the activity of antioxidase in this rat mastitis model. The results of Western blot analysis revealed that ATC could suppress the expression of toll-like receptor 4, phosphorylation of extracellular signal-regulated kinase, and activity of c-Jun N-terminal kinase in the LPS-stimulated mastitis model. Conclusion Taken together, ATC was shown to exert its anti-inflammatory effect by blocking mitogen-activated protein kinase signaling pathways. These results demonstrate that ATC exerts anti-inflammatory and antioxidant effects in mastitis prevention.