Trichostrongylus colubriformis infection damages intestine brush board cells and could negatively impact postabsorptive parameters of Santa Ines lambs

Improve animal health to reduce livestock emissions: quantifying an open goal

Greenhouse gas (GHG) emissions from livestock production must be urgently tackled to substantially reduce their contribution to global warming. Simply reducing livestock numbers to this end risks impacting negatively on food security, rural livelihoods and climate change adaptation. We argue that significant mitigation of livestock emissions can be delivered immediately by improving animal health and hence production efficiency, but this route is not prioritized because its benefits, although intuitive, are poorly quantified. Rigorous methodology must be developed to estimate emissions from animal disease and hence achievable benefits from improved health through interventions. If, as expected, climate change is to affect the distribution and severity of health conditions, such quantification becomes of even greater importance. We have therefore developed a framework and identified data sources for robust quantification of the relationship between animal health and greenhouse gas emissions, which could be applied to drive and account for positive action. This will not only help mitigate climate change but at the same time promote cost-effective food production and enhanced animal welfare, a rare win-win in the search for a sustainable planetary future.

Interaction between methanotrophy and gastrointestinal nematodes infection on the rumen microbiome of lambs

Complex cross-talk occurs between gastrointestinal nematodes and gut symbiotic microbiota, with consequences for animal metabolism. To investigate the connection between methane production and endoparasites, this study evaluated the effect of mixed infection with Haemonchus contortus and Trichostrongylus colubriformis on methanogenic and methanotrophic community in rumen microbiota of lambs using shotgun metagenomic and real-time quantitative PCR (qPCR). The rumen content was collected from six Santa Inês lambs, (7 months old) before and after 42 days infection by esophageal tube. The metagenomic analysis showed that the infection affected the microbial community structure leading to decreased abundance of methanotrophs bacteria, i.e. α-proteobacteria and β-proteobacteria, anaerobic methanotrophic archaea (ANME), protozoa, sulfate-reducing bacteria, syntrophic bacteria with methanogens, geobacter, and genes related to pyruvate, fatty acid, nitrogen, and sulfur metabolisms, ribulose monophosphate cycle, and Entner-Doudoroff Pathway. Additionally, the abundance of methanogenic archaea and the mcrA gene did not change. The co-occurrence networks enabled us to identify the interactions between each taxon in microbial communities and to determine the reshaping of rumen microbiome associations by gastrointestinal nematode infection. Besides, the correlation between ANMEs was lower in the animal's postinfection. Our findings suggest that gastrointestinal parasites potentially lead to decreased methanotrophic metabolism-related microorganisms and genes.

Revealing the associated microflora hosted by the globally significant parasite Trichostrongylus colubriformis

Trichostrongylus colubriformis is a parasitic helminth that primarily infects small ruminants, causing substantial economic losses in the livestock industry. Exploring the microbiome of this helminth might provide insights into the potential influence of its microbial community on the parasite's survival. We characterised the intestinal microbiome of T. colubriformis that had been collected from the duodenum of sheep, and compared the helminth microbiome with the duodenal microbiome of its host, aiming to identify contributions from the helminth's environment. At the same time, we explored the isolation of fastidious organisms from the harvested helminth. Primary alpha and beta diversity analyses of bacterial species revealed statistically significant differences between the parasite and the host, in terms of species richness and ecological composition. 16S rRNA differential abundance analysis showed that Mycoplasmoides and Stenotrophomonas were significantly present in T. colubriformis but not in the duodenal microbiome of the sheep. Furthermore, two bacteria, Aeromonas caviae and Aeromonas hydrophila, were isolated from T. colubriformis. Examinations of the genome highlight differences in genome size and profiles of antimicrobial resistance genes. Our results suggest that T. colubriformis carries a specific bacterial community that could be supporting the helminth's long-term survival in the host's digestive system.