EFFECTS OF LEVELS OF INSOLUBLE AND SOLUBLE FIBRE IN DIETS FOR GROWING RABBITS ON FAECAL DIGESTIBILITY, NITROGEN RECYCLING AND IN VITRO FERMENTATION

[EN] The effect of neutral detergent fibre (NDF) and neutral detergent soluble fibre (NDSF) on in vivo faecal digestibility and caecal fermentation pattern was studied in growing rabbits, in four diets formulated according to two levels of NDF, 370 (LI) and 450 (HI) g/kg, and two levels of NDSF, 150 (LS) and 180 (HS) g/kg in substitution of starch, in a 2x2 factorial structure. Twenty four New Zealand White rabbits weaned at 28 d (630 ± 80.2 g weight) were allocated to digestibility cages from 42 to 49 d of age to determine apparent faecal digestibility of each diet (n=6). Urine was collected for determination of purine derivatives (PD). Once the digestibility trial finished, rabbits were fitted with PVC neck collars for 24 h total caecotrophe collection. After one day of recovery, animals were slaughtered and caecal contents were used as inocula for 18 h in vitro gas production and caecal degradation (ivDMcD) study, using an HCl-pepsin and pancreatin pre-digested substrate. Diet digestibility was also determined by the in vitro three-step enzymatic procedure. There were no effects of the NDF x NDSF interaction for any digestibility parameter (P>0.10). Both dry matter and organic matter digestibility (DMD and OMD) decreased from 0.518 to 0.442 and from 0.526 to 0.447, respectively, with the inclusion of NDF (P0.10). In contrast, NDF digestibility (NDFD) and ivDMcD did not respond to NDF (P>0.10) but increased from 0.156 to 0.200 and 0.141 to 0.210 with a ratio of NDSF (P<0.01). Weight of caecal contents increased with both NDF (P<0.001) and NDSF (P<0.01). However, total production of caecotrophes increased from 20.1 to 25.5 g DM/d with NDF (P<0.05), but was not affected by NDSF. The crude protein (CP) proportion in caecotrophes decreased with NDF (P<0.001) and increased with NDSF (P<0.01), and total CP recycled as caecotrophes tended (P=0.093) to be higher in HS diets, being unaffected by the dietary level of NDF. Diets rich in NDSF rendered higher gas volumes (P<0.001) than those with LS from 2 to 18 h incubation, whereas inclusion of high proportions of NDF reduced gas volume (P<0.01). Results indicate that NDF reduces faecal digestibility, whereas NDSF promotes better conditions for caecal fermentation.This work was financed through the Project AGL2006-07596, from the Ministry of Education and Science (Spanish Government). Ms. Norelys Rodríguez-Romero’s stage at in the University of Zaragoza was financed though a Doctoral fellowship from the Universidad Nacional Experimental del Táchira (Venezuela)Rodríguez-Romero, N.; Abecia, L.; Fondevila, M.; Balcells, J. (2011). EFFECTS OF LEVELS OF INSOLUBLE AND SOLUBLE FIBRE IN DIETS FOR GROWING RABBITS ON FAECAL DIGESTIBILITY, NITROGEN RECYCLING AND IN VITRO FERMENTATION. World Rabbit Science. 19(2):85-94. https://doi.org/10.4995/wrs.2011.828SWORD859419

Manipulating rumen microbiome and fermentation through interventions during early life: a review:Rumen manipulation in early life

The nutritional manipulations of the rumen microbiome to enhance productivity and health are rather limited by the resilience of the ecosystem once established in the mature rumen. Based on recent studies, it has been suggested that the microbial colonisation that occurs soon after birth opens a possibility of manipulation with potential to produce lasting effects into adult life. This paper presents the state-of-the-art in relation to early-life nutritional interventions by addressing three areas: the development of the rumen as an organ in regards to the nutrition of the new-born, the main factors that determine the microbial population that first colonizes and establishes in the rumen, and the key immunity players that contribute to shaping the commensal microbiota in the early stage of life to understand host-microbiome specificity. The development of the rumen epithelium and muscularization are differently affected by the nature of the diet and special care should be taken with regards to transition from liquid (milk) to solid feed. The rumen is quickly colonized by all type of microorganisms straight after birth and the colonization pattern may be influenced by several factors such as presence/absence of adult animals, the first solid diet provided, and the inclusion of compounds that prevent/facilitate the establishment of some microorganisms or the direct inoculation of specific strains. The results presented show how early-life events may be related to the microbial community structure and/or the rumen activity in the animals post-weaning. This would create differences in adaptive capacity due to different early life experiences and leads to the idea of microbial programming. However, many elements need to be further studied such as: the most sensitive window of time for interventions, the best means to test long term effectiveness, the role of key microbial groups and host-immune regulations

Hesteetako hanturazko gaixotasuna: patogenia, tratamenduak eta mikrobiotan oinarritutako biomarkatzaileak

Inflammatory bowel disease (IBD) encompasses two types of idiopathic intestinal diseases, ulcerative colitis (UC) and Crohn’s disease (CD). Both are chronic, heterogeneous, and severe inflammatory disorders that primarily affect the intestine. IBD has emerged as a global disease with a sharp increase in worldwide incidence and prevalence. Although the specific underlying cause of UC is unknown, it is considered the result of a complex interaction between the microbiota, immune system, host genetics and environmental factors. The advent of new technologies has enabled the identification of disturbed microbiota composition and function and reduced microbial diversity in IBD pa-tients, termed dysbiosis. Obtained clinical and experimental data points dysbiosis as a key player in IBD pathogenesis, but it is still unclear whether it is the cause of consequence. Although a wide range of therapies are approved for use as treatment for IBD, there is no cure. TNF inhibitors are frequently used to induce clinical remission in severe patients, however a roughly one third of the patients may not respond, and another third may lose response over time. In addition, the cost associated with IBD treatments is increasing over time, mainly due the costs associated with the biologic treatment. Emerging evidence has pointed towards gut microbiota to find a set of biomarkers for diagnosis, and for prediction of disease severity and infliximab treatment response in IBD patients. The human fecal microbiota harbors promising and non-invasive biomarkers, which emphasizes its potential ability to stratify IBD patients and apply personalized therapy for optimal outcomes.; Hesteetako hanturazko gaixotasunak (HHG, ingelesez IBD) bi gaixotasun idiopatiko ezberdin biltzen ditu, ultzeradun kolitisa (UK) eta Crohn-en gaixotasuna (CG). Biak batez ere hesteari eragiten dioten gaixotasun kronikoak, heterogeneoak eta larriak dira. HHGa handitzen ari den gaixotasun globala da, eta haren intzidentzia eta prebalentzia areagotuz doa mundu osoan. UKaren kausa zehatza ezezaguna bada ere, uste da mikrobiotaren, sistema immunearen, ostalariaren genetikaren eta ingurumen-faktoreen arteko elkarrekintza konplexuaren ondorioz sortzen dela. Genomikako teknologia berriek HHG-pazienteetan mikrobiotaren osaeran eta funtzioan aldaketak identifikatzea ahalbidetu dute. Aldaketa horiek disbiosia bezala ezagutzen dira. Lortutako datu kliniko eta esperimentalak, disbiosia, HHGen funtsezko eragile gisa finkatzen dute, nahiz eta oraindik argi egon ez kausa edo ondorioa den. Gaur egun H HGaren aurkako tratamendu ugari dauden arren, ez dago sendabide-H HGaren aurkako tratamendu ugari dauden arren, ez dago sendabide- aurkako tratamendu ugari dauden arren, ez dago sendabide-rik. Paziente larrietan sintomatologia arintzeko, TNF inhibitzaileak dira gehien erabiltzen den tratamendua. Hala ere, pazienteen heren batek ez dio tratamenduari erantzuten eta beste heren batek denborarekin erantzuna galtzen du. Gainera, tratamenduei lotutako kostu ekonomikoa eten-gabe handitzen ari da, batez ere tratamendu biologikoen kostuengatik. HHGa duten gaixoen hesteetako mikrobiota baliagarri bilakatzen ari da gaixotasuna diagnostikatzeko, gaixotasunaren larritasuna zehazteko eta tratamenduarekiko erantzuna iragartzeko, hau da, mikrobiotaren osaera biomarkatzaile gisa erabil daiteke. Izan ere, giza gorotzetako mikrobiota biomarkatzaile esperantzagarri eta ez-inbaditzaile bihurtu da. Mikro-biotaren azterketak HHGa duten gaixoak sailkatzeko aukerak gehitzen ditu, eta tratamendu pertsonalizatuen aukera zabaldu

TLR2 and TLR4 interact with sulfide system in the modulation of mouse colonic motility

Background H2S is a neuromodulator that may inhibit intestinal motility. H2S production in colon is yielded by cystathionine beta-synthase (CBS) and cystathionine gamma-lyase (CSE) enzymes and sulfate-reducing bacteria (SRB). Toll-like receptors (TLRs) recognize intestinal microbiota. The aim of this work was to evaluate the influence of TLR2 and TLR4 on the endogenous and SRB-mediated synthesis of H2S and its consequences on the colonic motility of mouse. Methods Muscle contractility studies were performed in colon from WT, Tlr2(-/-), and Tlr4(-/-) mice. The mRNA levels of TLR2, TLR4, CBS, CSE, and SRB were measured by real-time PCR. Free sulfide levels in colon and feces were determined by colorimetric assays. Results NaHS and GYY4137, donors of H2S, reduced the contractility of colon. Aminooxyacetic acid (AOAA), inhibitor of CBS, and D-L propargylglycine (PAG), inhibitor of CSE, increased the contractility of colon. In vivo treatment with NaHS or GYY4137 inhibited the spontaneous contractions and upregulated TLR2 expression. The in vivo activation of TLR4 with lipopolysaccharide increased the contractile response to PAG, mRNA levels of CSE, and the free sulfide levels of H2S in colon. In Tlr2(-/-) and Tlr4(-/-) mice, the contractions induced by AOAA and PAG and mRNA levels of CBS and CSE were lower with respect to WT mice. Deficiency of TLR2 or TLR4 provokes alterations in free sulfide levels and SRB of colon. Conclusions and Inferences Our study demonstrates interaction between TLR2 and TLR4 and the sulfide system in the regulation of colonic motility and contributes to the pathophysiology knowledge of intestinal motility disorders

An Antimethanogenic Nutritional Intervention in Early Life of Ruminants Modifies Ruminal Colonization by Archaea

The aim of this work was to study whether feeding a methanogen inhibitor from birth of goat kids and their does has an impact on the archaeal population colonizing the rumen and to what extent the impact persists later in life. Sixteen goats giving birth to two kids were used. Eight does were treated (D+) with bromochloromethane after giving birth and over 2 months. The other 8 goats were not treated (D−). One kid per doe in both groups was treated with bromochloromethane (k+) for 3 months while the other was untreated (k−), resulting in four experimental groups: D+/k+, D+/k−, D−/k+, and D−/k−. Rumen samples were collected from kids at weaning and 1 and 4 months after (3 and 6 months after birth) and from does at the end of the treating period (2 months). Pyrosequencing analyses showed a modified archaeal community composition colonizing the rumen of kids, although such effect did not persist entirely 4 months after; however, some less abundant groups remained different in treated and control animals. The different response on the archaeal community composition observed between offspring and adult goats suggests that the competition occurring in the developing rumen to occupy different niches offer potential for intervention