Non-invasive Assessment of Fecal Stress Biomarkers in Hunting Dogs During Exercise and at Rest

Abstract

Intense exercise causes to organisms to have oxidative stress and inflammation at the gastrointestinal (GI) level. The reduction in intestinal blood flow and the exercise-linked thermal damage to the intestinal mucosa can cause intestinal barrier disruption, followed by an inflammatory response. Furthermore, the adaptation to exercise may affect the gut microbiota and the metabolome of the biofluids. The aim of the present research was to evaluate the presence of a GI derangement in hunting dogs through a non-invasive sampling as a consequence of a period of intense exercise in comparison with samples collected at rest. The study included nine dogs that underwent the same training regime for hunting wild boar. In order to counterbalance physiological variations, multiple-day replicates were collected and pooled at each experimental point for each dog. The samples were collected immediately at rest before the training (T0), after 60 days of training (T1), after 60 days of hunting wild boar (T2), and finally, at 60 days of rest after hunting (T3). A number of potential stress markers were evaluated: fecal cortisol metabolites (FCMs) as a major indicator of altered physiological states, immunoglobulin A (IgA) as an indicator of intestinal immune protection, and total antioxidant activity [total antioxidant capacity (TAC)]. Since stool samples contain exfoliated cells, we investigated also the presence of some transcripts involved in GI permeability [occludin (OCLN), protease-activated receptor-2 (PAR-2)] and in the inflammatory mechanism [interleukin (IL)-8, IL-6, IL-1b, tumor necrosis factor alpha (TNFα), calprotectin (CALP), heme oxygenase-1 (HO-1)]. Finally, the metabolome and the microbiota profiles were analyzed. No variation in FCM and IgA content and no differences in OCLN and CALP gene expression between rest and training were observed. On the contrary, an increase in PAR-2 and HO-1 transcripts, a reduction in total antioxidant activity, and a different profile of microbiota and metabolomics data were observed. Collectively, the data in the present study indicated that physical exercise in our model could be considered a mild stressor stimulus.

The gut microbiome buffers dietary adaptation in Bronze Age domesticated dogs

“…Ancient bacterial reads were then retrieved from the metagenomes of the Solarolo coprolites and used to reconstruct the putative GM of the corresponding Bronze Age dogs. According to our findings, the GM of Solarolo dogs showed a general layout matching the modern canine GM, with notably members of the Peptostreptococcaceae, Lachnospiraceae, Prevotellaceae, and Fusobacteriaceae families (Alessandri et al, 2019;Gaspardo et al, 2020;Pilla and Suchodolski, 2020;Zannoni et al, 2020). The GM compositional structure of Solarolo dogs shared features with both modern wild wolves and domesticated dogs, likely reflecting a transitional state between the GM of the wolf and that of the fully domesticated modern dog.…”

“…In brief, taxa with more than 500 assigned reads, more than 50 reads with postmortem degradation score (PMDS) > 1, ÀD % (negative difference proportion of PMDS >1 reads) > 0.9 and showing patterns of C-T transition at 5 0 were considered to be of ancient origin (see Table 1 and Figure S2 for C-T transition at 5 0 and edit distance distribution). A large number of reads assigned to previously identified canine GM taxa (Alessandri et al, 2019;Gaspardo et al, 2020;Pilla and Suchodolski, 2020;Zannoni et al, 2020) sustained deamination and substitution profiles that are consistent with that of ancient DNA (e.g., Ruminococcus bromii, Collinsella intestinalis, Enterococcus faecalis, Faecalibacterium prausnitzii, Roseburia faecis, and Prevotella copri).…”

“…By using this approach, we were able to detect several host-associated microorganisms in the Solarolo coprolites. In particular, components of the mammalian and, especially, canine GM were identified (Alessandri et al, 2019;Gaspardo et al, 2020;Pilla and Suchodolski, 2020;Zannoni et al, 2020), including members of the families Peptostreptococcaceae, Lachnospiraceae, Prevotellaceae, and Fusobacteriaceae. As expected for coprolite samples, members of bacterial Phylogeny is based on mtDNA of Solarolo dogs as compared with publicly available canine mtDNAs, including ancient wolf-like and dog-like whole mtDNA sequences, mtDNA sequences from a comprehensive panel of modern dogs across four major clades (A-D) (Thalmann et al, 2013;Frantz et al, 2016;Botigué et al, 2017), and mtDNA sequences from metagenomic studies (Lyu et al, 2018;Alessandri et al, 2019).…”

“…The filtered reads were first aligned to the reference database using a modified version of MALT (Herbig et al, 2016;Vå gene et al, 2018), then the reads assigned to bacterial genomes were extracted with the MaltExtract tool and realigned to their respective reference genomes to examine edit distances, coverage distributions, and post-mortem DNA damage patterns (Key et al, 2017;Hü bler et al, 2019;Rampelli et al, 2021). In particular, we chose to extract and further investigate bacterial species of canine origin (i.e., already detected within the stool microbiome of C. lupus or C. lupus familiaris in other studies) (Alessandri et al, 2019;Gaspardo et al, 2020;Pilla and Suchodolski, 2020;Zannoni et al, 2020), with R 500 assigned reads (including strainspecific reads). For this purpose, we applied bwa aln with the same options used for the host analysis (-l 16500 -n 0.01 -o 2).…”

Acute Diarrhea in Dogs: Current Management and Potential Role of Dietary Polyphenols Supplementation

“…Given the above, in vivo and in vitro studies [ 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 ] have been performed to elucidate possible protective mechanisms of dietary antioxidant compounds in the treatment of intestinal inflammation and redox imbalance, with particular attention to natural polyphenols. Polyphenols represent a great variety of compounds occurring in fruits, vegetables, and plant-derived products.…”