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Pasture dieback is a syndrome of unknown cause affecting grasses in Australia, creating significant economic losses to farmers by reducing available livestock feed and paddock carrying capacity. RC3 is a commercial plant growth stimulant tri-sodium salt of trimercapto-S-triazine (TMT) and potassium humate as active ingredients. TMT is commonly used for soil and wastewater remediation by capturing and binding heavy metals, while potassium humate is an organic compound used as a plant growth promoter. We investigated the ability of RC3 to restore soil health and productivity under pasture dieback conditions. RC3 was applied on pasture dieback affected paddock replicate plots once, at a rate of 4 mL/m2, and soil core samples were taken weekly to analyse microbial communities. Plants were collected regularly to measure dry matter and plant morphometrics. Twenty weeks after a single application, dry matter increased in RC3 plots by 900 kg/ha compared to control plots, and at week 48, eleven months after the single application, RC3 plots showed a trend of more grass and dicot species than the control. Morphometric measures suggest minor improvements in dicotyledon plants. Alpha diversity did not change with the application of RC3. Temporal correlation analysis shows that RC3 steadily reduced the presence of genera predominant in poor soils and with extreme environmental conditions over time and prevented the decline of beneficial genera, such as Marmoricola, Actinomadura, Dactylosporangium, and mle1-7. [ABSTRACT FROM AUTHOR]

The removal of antibiotics from the feeds used in the livestock industry has resulted in the use of a wide range of alternative antimicrobial products that aim to deliver the productivity and health benefits that have traditionally been associated with antibiotics. Amongst the most popular alternatives are phytogenic product-based extracts from herbs and spices with known antimicrobial properties. Despite embracing such alternatives, the industry is still largely unaware of modes of action, their overall effects on animal health, and interactions with other feed additives such as probiotics. To address some of these issues, three phytogenic products were selected and their interactions with caecal microbiota of layers, grown under six different production systems, were investigated in vitro. Caecal microbiotas were grown with and without phytogenic products, and the changes in microbiota composition were monitored by sequencing of 16S rRNA gene amplicons. Phytogenic products and production system both significantly influenced microbiota composition. The three phytogenic products all altered the relative abundance of species within the Lactobacillus genus, by promoting the growth of some and inhibiting other Lactobacillus species. There were also significant alterations in the Bacillus genus. This was further investigated by comparing the effects of the phytogenic products on the growth of a commercially used Bacillus-based probiotic. The phytogens affected the probiotic mix differently, with some promoting the growth of Bacillus sp. at lower phytogenic concentrations, and fully suppressing growth at higher concentrations, indicating the importance of finding an optimal concentration that can control pathogens while promoting beneficial bacteria. Key points: • After removal of antibiotics from animal feed, urgent solutions for pathogen control were needed. • Alternative products entered the market without much knowledge on their effects on animal health. • Probiotic products are used in combination with phytogens despite the possible incompatibility. [ABSTRACT FROM AUTHOR]

Simple Summary: The use of phytogenic products has entered mainstream use in the livestock industry as an antibiotic alternative. These products, often based on herbs and spices with established antimicrobial properties, are generally considered as safe and natural, however, they are often administered in high doses and frequency. The direct effects of these products on the livestock animals remains under-reported. Using a transcriptomics, we show that supplementing 2% oregano in feed has direct effects on gene expression in the livers of broilers with a potential range of beneficial and negative side effects. Pathogen control is re-emerging as a significant challenge to the health of both humans and animals. The livestock industry is in the process of massively replacing in-feed antibiotics with organic production friendly plant-based products. Nutrigenomics as a science of the effects of food constituents on gene expression is shedding more light on both benefits and detrimental side-effects of feed additive prolonged consumption on the host, indicating the need to understand the feed-host interactions and their influence on the host disease profile. In this study, we investigated the effects of 2% oregano powder supplementation on the liver gene expression in healthy male broilers from the hatch to 6 weeks of age. Deep RNAseq was performed on average 113.3 million paired and quality trimmed sequences per sample and four samples for the control and treatment each. The results demonstrate the severity of oregano effect on liver gene expression with substantial modifications in steroid hormone regulation, fat and carbohydrate metabolism alterations and strong influence on the host disease and function profile. Oregano supplementation was able to interfere with the transcriptional effects of a range of registered drugs and to significantly transcriptionally inhibit a range of cancer disease categories including liver cancer, and to modify fat and carbohydrate metabolism. [ABSTRACT FROM AUTHOR]

Microbial colonisation of the gastrointestinal tract of newly hatched chicks starts at hatch, seeded from the immediate hatching environment, and quickly results in dense colonisation. The role of ecological factors in gut colonisation has been extensively investigated, as well as the role of micro- and macronutrients in supporting and selecting for bacterial species highly adapted for utilising those nutrients. However, the microbial community contained in poultry feed and its influence on colonisation and maturation of gut microbiota has not been directly addressed. In this study, we compared the microbiota found in poultry feed, with the microbiota of ileum, cecum and excreta, to identify substantial overlap in core microbiotas of the compared groups. We then investigated the microbiota present in raw feedstuffs: meat and bone meal, wheat, corn, canola, barley, soybean, millrun, sorghum, poultry oil, oats, limestone and bloodmeal from four geographically distinct feedstuff suppliers. Each of the feedstuffs had diverse microbial communities. The meat and bone meal and bloodmeal samples had the most complex and distinct microbial populations. There was substantial overlap in the phylogenetic composition found in the grain and seed samples: barley, canola, corn, millrun, oats, sorghum, soybean meal and wheat. Issues related to methodology, viability of microbial communities in the gut and feed, and the implications for biosecurity are discussed. [ABSTRACT FROM AUTHOR]