(Tech Support Feed Dig, Adisseo, France)
Increase in protein digestibility was total tract or ileal? If total, what’s the benefit of increased protein fermentation in the colon...?
I presented studies based on ileal and fecal digestibilities, but I supposed you are talking the one based on total tract. Anyway, the improvement on protein digestibility will decrease the protein in the intestinal tract, changing the microbiota profile, and improving the short chain fatty acid production.
Dr Estelle BONNIN
(BIA, INRA Nantes, France)
What is the variability of NSP structure within each cereal?
As shown in the presentation, the most common polysaccharides in cereal cell wall are arabinoxylan and beta-glucan. But other polysaccharides are also present: cellulose, mannan… the proportion of each fully depends on the cereal considered.
What does HX stand for and when do you expect to publish the data on maize endosperm NSP structure?
HX stand for heteroxylan, that means a structure made of a xylan backbone and carrying not only arabinose as side chains but much more complex side chains with glucuronic acid, galactose, xylose… We are still collecting structural results on maize endosperm HX.
How rovabio act on feed inducing immuno response in soybean?
To date, the nature of the hydrolysis products released in the gut in the presence of soybean and Rovabio is not known.
Is the transitory increase in viscosity by hydrolysing insoluble NSP cancelled out by the decrease in viscosity by hydrolysing soluble NSP?
It depends on the selectivity of the xylanase. Selectivity = relative activity on insoluble and soluble substrates. The 'solubilising xylanases' are most active on insoluble AX and thus induce first an increased viscosity. The 'degrading xylanases' are most active on soluble AX and thus induce the decreased viscosity from the beginning of the degradation.
Should we develop enzymes focusing more on disubstituted Xylose?
If we want to degraded extensively the arabinoxylan, the answer would be yes. But for animal feeding, we showed previously that even hydrolysis products from wheat with chain length of a few tens of residues have prebiotic effect, suggesting that it is not necessary to reach an extensive degradation to have a beneficial effect in broiler (Yacoubi et al., 2018, Poult. Sci. 97: 412-424). But you can also read Rose et al (2010), who stated that in wheat arabinoxylan, bacteria utilize first the unsubstituted xylose region (Agric. Food Chem 58: 493-499).
Could you comment on the need to have feruloyl est erase activity to better degrade AX of cereals?
Ferulic acid is partly responsible of the unsolubility of arabinoxylan, as it forms dimer bridges between chains. Some feruloylesterases (but not all) are able to split the linkages with the ferulic dimer and thus participate to the solubilisation of arabinoxylans.
Just few coments : could you provide aditional information about Soissons and Valoris?
Valoris is richer than Soissons in soluble arabinoxylans and as a consequence it is a more viscous variety. In the paper by Maisonnier-Grenier et al (J Sci Food Agric 86:1714–1721 (2006)), you will find all the data on the cultivars used in this study.
Which type of enzymes do we need to Use for Soya Bean Meal?
Cellulose- and pectin-degrading enzymes have to be studied in more detail. Also the hemicellulosic fraction present in SBM is not yet fully characterized.
What’s driving increased energy release from hydrolysis of AX if monomers are 5 carbon sugars... bacterial fermentation ?
It is unlikely that monomers are released in the gut, and that the hydrolysis products participate directly to the energy. From what we know to date, the improvement of animal performance is more linked to the beneficial microflora that can develop in these conditions and notably the effects of the short chain fatty acids that are produced.
It is interesting to use beta glucanase in maize soya feed ? And not only xylanase?
There is no beta-glucan in soya, this activity will not help.
Have you work un the peas ?
Long time ago, we characterised xylogalacturonans in pea hulls (LeGoff et al, 2001, Carbohydr Pol 45, 325-334). The same structure is present in the pectin of soybean seeds.
Prof M. RODEHUTSCORD
(Hohenheim Univ, Germany)
Do you think microflora in broiler gut have a role in degradation of phytate p.?
Yes, I do believe. However, not well understood and not quantified yet.
Is the enzyme still active un the environnement ?
EU requires prove that enzymes are not harmful for the environment before approval. Would expect some phytase to be contained in faeces; however of mixed sources (added, endogenous, mirobial)
Phytic acid forms a complex with Ca at pH >3 which is not dissolvable. May different feed composition slow down phytase break down of phytic acid?
Yes, details of feed composition that manipulate gastrointestinal pH do affect phytase efficacy.
Do you think , expermintaly of we still adding phytate we can reach 100% release of Inositol and 0 phytate ?
I guess the maximum is around 90% at very high dosages and including degradation of lower inositol phosphates. Feed fermentation may help to achieve complete degradation.
What about adding the pure inositol as feed supplements in poultry feed ?
Few studies have shown beneficial effects on FCR and several metabolites. Definitely worth to be more studied. In some fish species, requirements for inositol are provided.
Is adding more phytase (more than 1500u) can lead fibaly to 100 free inositole? What's the impact on the birds ? The added value
see answers before
What should be the ratio of Ca/Av.P? Breeders says, it must be 2.
Working with unspecified avP is nonsens
Dr Pierre COZANNET (CERN, Adisseo, France)
Why if.... prediction for body weight and feed intake is r2=99... why prediction for FCR is r2=0,87? What is affecting?
Body weight and feed intake varied in very large extend making prediction easy. FCR range was narrower. These differences probably explained the change in prediction quality.
Can we trust "Adisseo Predictor Tool" to see our diet's NSP levels or further studies needed?
Adisseo predictor did not provide any information regarding NSP content. Improvement are currently under evaluation for those aspects
Dr Lamya RHAYAT (CERN, Adisseo, France)
How the colonization time of probiotic affect on dosage of it on feed , what is the ideal time needed?
Unfortunately, I can't answer to this question. Our probiotic Alterion doesn't colonize the gut. So, it has to be added in feed to give it to the birds daily. The most important point is that it is able to germinate in the gut and by doing this, it is able to provide its beneficial effect to the host (directly or via the microbiota). For the other probiotics potentially able to colonize the gut, I suppose that the optimal dosage (or time for giving the probiotic to the birds) depends on the probiotic strain used.
How did you control the agents that can effect Ig A or Ig G levels in the trial?
Not sure to know what are the 'agents' here. If we are talking about the AX released from the feed after the digestion of the diet with Rovabio, we are not able to control them but the initial diet/feedstuff determine the potential AX.