Assessing the impact of phyllosphere microbiota on dynamics of in-silo fermentation of Italian ryegrass harvested at heading and blooming stages.

BACKGROUND: The present study aimed to investigate the relationship between the phyllosphere microbiota of Italian ryegrass (Lolium multiflorum Lam.) harvested at heading (H) [> 50% earing rate or 216 g kg-1 fresh weight (FW)] and blooming (B) (> 50% bloom or 254 g kg-1 FW) stages and in-silo fermentation products, and the composition, abundance, diversity and activity of bacterial community. In total, 72 (4 treatments × 6 ensiling durations × 3 replicates) laboratory scale (400 g) silages of Italian ryegrass were prepared: (i) irradiated heading stage silages (IRH) (n = 36) were inoculated with phyllosphere microbiota inoculum (2 mL) eluted from fresh Italian ryegrass at either heading (IH) (n = 18) or blooming (IB) (n = 18) stages; (ii) irradiated blooming stage silages (IRB) (n = 36) were inoculated with either IH (n = 18) or IB (n = 18). Triplicate silos of each treatment were analyzed after 1, 3, 7, 15, 30 and 60 days of ensiling. RESULTS: In fresh forage, Enterobacter, Exiguobacterium and Pantoea were the three major genera at heading stage, and Rhizobium, Weissella and Lactococcus were the most abundant genera at blooming stage. Higher metabolic activity was found in IB. After 3 days of ensiling, the large amounts of lactic acid in IRH-IB and IRB-IB can be attributed to the higher abundances of Pediococcus and Lactobacillus, 1-phosphofructokinase, fructokinase, l-lactate dehydrogenase and glycolysis I, II and III. CONCLUSION: The composition, abundance, diversity and functionality of the phyllosphere microbiota of Italian ryegrass at different growth stages could remarkably affect silage fermentation characteristics. © 2023 Society of Chemical Industry.

Exploring the Epiphytic Microbial Community Structure of Forage Crops: Their Adaptation and Contribution to the Fermentation Quality of Forage Sorghum during Ensiling.

In this study, the effects of epiphytic microbiota from different forages on the fermentation characteristics and microbial community structure of forage sorghum silage were investigated. The gamma irradiated sterilized forage sorghum was treated through sterile water, epiphytic microbiota of forage sorghum (FSm), Sudan grass (SDm), Napier grass (NPm), and maize (MZm). NPm and SDm inoculated silages showed similar pH value and lactic acid (LA) and acetic acid (AA) contents at day 3 and 60 of ensiling. The final silage of FSm and MZm showed lower (p < 0.05) pH and AA content and a higher LA content compared to the NPm and SDm silages. Bacterial species from the Weisella genus were predominantly present in FSm, NPm, and SDm, while Lactococcus dominated the MZm silage during early ensiling. Lactobacillus was predominant in all inoculated terminal silages. Overall, the four inoculated microbiota decreased the pH value of silage and were dominated by lactic acid bacteria (LAB); however, the NPm and SDm treatments resulted in comparatively higher AA contents which could have an inhibitory effect on the secondary fermentation developed by the yeast and enhanced the aerobic stability of forage sorghum silage.

Abundance and diversity of epiphytic microbiota on forage crops and their fermentation characteristic during the ensiling of sterile sudan grass.

This study aimed to evaluate the effects of exogenous epiphytic microbiota inoculation on the fermentation quality and microbial community of sudan grass silage. Gamma irradiated sudan grass was ensiled with distilled water (STR), epiphytic microbiota of sudan grass (SUDm), forage sorghum (FSm), napier grass (NAPm) and whole crop corn (WCCm). The FSm inoculated silage have significantly lower lactic acid (LA) concentration and higher pH during early ensiling, while LA concentration gradually and significantly increased with the progression of ensiling and have lower pH in relation to other treatments for terminal silage. Inoculation of NAPm resulted in lower LA and higher acetic acid (AA) concentrations, higher pH, ammonia-N and dry matter losses for terminal silage, followed by SUDm silage. Inoculations of WCCm significantly increased LA production and pH decline during early ensiling and have higher LA and pH then NAPm and SUDm silages during final ensiling. The early fermentation of SUDm silage was dominated by genus of Pediococcus. The genera of Lactobacillus were predominant in WCCm and NAPm silages during 3 days of ensiling, while Weissella dominated initial microbial community of FS silage. The terminal silage of NAPm was dominated by Enterobacter and Rosenbergiella, while Enterobacter and Lactobacillus dominated terminal SUDm silage. The final silage of FSm was dominated by Lactobacillus, Weissella and Pediococcus, while Lactobacillus and Acetobacter dominated terminal WCCm silages. The results demonstrated that among the four forages the epiphytic microbiota from forage sorghum positively influenced the microbial community and fermentability of sudan grass silage.

Sequencing and microbiota transplantation to determine the role of microbiota on the fermentation type of oat silage.

This study was aimed to assess the effects of exogenous microbiota on fermentation quality and bacterial community dynamics in oat (OT) silage. The irradiated OT was treated with the following: (i) sterile water (STOT); (ii) epiphytic microbiota on oat (OTOT); (iii) epiphytic microbiota on maize (OTMZ); (iv) epiphytic microbiota on sorghum (OTSG). γ-Ray irradiation, microbiota transplantation and sequencing methods were firstly used. After 60 days of ensiling, OTMZ group had higher lactic acid (LA) and lower acetic acid (AA) contents than OTOT group. Inversely, lower LA content and higher ratio of LA to AA was observed in OTSG group than OTOT group. Lactobacillus was predominant in OTMZ-60 group, while Lactobacillus and Enterobacteriaceae were both dominant in OTSG-60 group. Overall, the higher amounts of Enterobacteriaceae and heterofermentative Lactobacillus are conductive to acetic acid-type fermentation, and forage microbiota transplantation may be a potential way to identify the role of microbe during ensiling.

Maternal Exposure to T-2 Toxin Affects Puberty Genes and Delays Estrus Cycle in Mice Offspring.

Among foodborne toxicities, the T-2 toxin is the most toxic member of trichothecenes mycotoxins, which has been shown to impair the development and reproductive efficiency of animals. Pups are particularly more quickly prone to programming the effects of the maternal diet during the gestational and lactation periods. Few studies have reported the maternal toxic effect on the next generation. Dams were served the T-2 toxin at a dose of 0.005 and 0.05 mg/kg body weight/day and control group 0 mg/kg from gestation day 14 to lactation day 21. Female mice offspring were selected at the weaning age. Our observations indicate that age during the vaginal opening and di-estrus stage increased and the length of the estrus cycle, first di-estrus, and regular estrus cycling were delayed with prolonged di-estrus in the 0.05 mg/kg group compared to the 0.005 mg/kg and control group. Transcription level analysis showed that mice at a dose of 0.05 mg/kg exhibited a decrease in hypothalamic mRNA expression of Gnrh and Gnrhr, Lhb, and Fshb in the pituitary gland, with a significant decrease of Fshr and Lhr in the ovaries. Present findings report that postnatal exposure to the T-2 toxin delayed puberty age in female mice and induced oxidative stress, ovarian damage, and reduced vaginal epithelium wall majorly in the 0.05 mg/kg group, and showed fewer effects in the 0.005 mg/kg group.

The feasibility and effects of exogenous epiphytic microbiota on the fermentation quality and microbial community dynamics of whole crop corn.

This study analyzed the feasibility and effects of exogenous epiphytic microbiota on the fermentation quality and microbial community of whole crop corn. Gamma irradiated whole crop corn was ensiled with distilled water (STR), extracted microbiota of whole crop corn (WCC), Napier grass (NAP), forage sorghum (FS) or Sudan grass (SUD). WCC significantly increased LA concentration and decreased the pH during early ensiling. FS had significantly higher LA and lower pH during terminal ensiling. NAP caused higher pH and AA followed by the SUD silage. During 3 d of ensiling WCC and FS silage was dominated by Lactobacillus and Lactococcus while Weissella dominated NAP and SUD silage. Terminal silage was dominated by Lactobacillus in FS and Acinetobacter in NAP while Lactobacillus, Acetobacter, Acinetobacter and Sphingobium dominated WCC and SUD silage. The study demonstrated that FS microbiota transplantation positively influenced the microbial community and fermentation quality of whole crop corn silage as compared to other microbiota.

Maternal Exposure to T-2 Toxin Induces Changes in Antioxidant System and Testosterone Synthesis in the Testes of Mice Offspring.

T-2 toxin, the most toxic member of trichothecene mycotoxin, is widely distributed in cereals, and has been extensively studied, but few studies focus on the toxicity of maternal exposure to offspring. This study focused on the effects of maternal exposure to T-2 toxin (during gestation and lactation) on the testicular development of mice offspring. Dams were orally administered with T-2 toxin at 0, 0.005, or 0.05 mg/kg body weight from the late stage of gestation to the end of lactation. Testicular samples of the mice offspring were collected on the postnatal day 21, 28, and 56. The results showed significant decreases in body weight and testicular weight on the postnatal day 28. Moreover, significant inhibition of antioxidant system and testosterone synthesis was detected on the postnatal day 28. Furthermore, there were significant decreases in the gene expression levels of StAR and 3ß-HSD, which are involved in testosterone synthesis. In general, present results demonstrated that maternal exposure to T-2 toxin during gestation and lactation led to bad effects on the capacity of antioxidant system and inhibited testosterone synthesis in testes during pre-puberty with no significant effects on post-puberty.