Several investigations have suggested that fenugreek seeds may have a hypocholesterolemic activity, and thus be efficient in the treatment of egg yolk cholesterol. The objective of the current study was to evaluate the effect of dietary incorporation of 3% of fenugreek seed combined with 3% of linseed, 1% of garlic paste, and 0.078% of copper sulfate on laying performance, egg quality and lipids profile. Forty four, 41 weeks old, Novogen White laying hens received for 42 days 100 g/d of basal diet (control) or experimental diet (CFSGLSCS). With the exception of egg weight, which showed a significant increase for hens fed on CFSGLSCS with 57.99 g compared to 56.34 g for the control group, egg production (90.84% for control compared to 87.89% for experimental diet), egg mass (50.95 g/d for control compared to 50.87 g/d for CFSGLSCS), feed efficiency (1.94 for control compared to 1.98 for CFSGLSCS) were not affected by dietary treatments. The addition of CFSGLSCS reduced (p < 0.05) egg yolk cholesterol by 5.4% and blood cholesterol from 158.42 mg/dL to 122.82 mg/dL for control and CFSGLSCS, respectively. The dietary addition of CFSGLSCS increased (p < 0.05) total lipids from 4.5 g/egg to 5.23 g/egg and didn’t affect (p > 0.05) yolk triglycerides.

Some components of soluble fibre appear to have prebiotic effects that can contribute to improving digestive health in post-weaning rabbits. In this work, a fenugreek seed gum (FGS), extracted from Trigonella foenum-graecum seeds and rich in galactomannan, was characterised. Both the pure FSG and ten substrates obtained by the inclusion of 0, 5, 10, 15 and 20 g/kg of FSG in diets rich in soluble (SF) and insoluble (IF) fibre were evaluated in vitro to determine FSG prebiotic potential for rabbit diets. FSG was rich in total sugars (630 g/kg dry matter), consisting entirely of galactose and mannose in a 1:1 ratio, and a moderate protein content (223 g/kg dry matter). Pure FSG was affected very little by in vitro digestion, as only 145 g/kg of the FSG was dissolved during the enzymatic phase. However, the linear inclusion of FSG up to 20 g/kg in growing rabbit feeds has led to a reduction in the solubility of some nutrients during in vitro enzymatic phase, especially in SF diets. Pure FSG not digested during the enzymatic phase almost completely disappeared during the in vitro fermentation phase, 984 g/kg of this indigestible fraction. However, although linear inclusion of FSG up to 20 g/kg in SF diets increased the fermented fraction, no relevant changes in the fermentation profile were observed. In conclusion, FSG satisfies two essential conditions of the prebiotic effect, showing resistance to in vitro enzymatic digestion and being totally fermented in vitro by caecal bacteria, although in vivo studies will be necessary to determine its prebiotic potential.

<p>This study aims to determine the effect of dietary inclusion of fenugreek seed gum (FSG), rich in galactomannans, on nutrient apparent digestibility and caecal environment, as well as on <em>in vitro</em> caecal fermentation of Tunisian growing rabbits. Three experimental diets were formulated, including 0, 0.25 and 0.5% of FSG (FSG0, FSG0.25 and FSG0.5, respectively) for the <em>in vivo</em> trial and 0, 0.125, 0.25, 0.5 and 100% of FSG (FSG0, FSG0125, FSG0.25, FSG0.5 and FSG100, respectively) for the <em>in vitro</em> trial. In the <em>in vivo</em> trial, 45 weaned rabbits 31 d old (15 per treatment) were housed in individual cages until 94 d of age. Apparent digestibility coefficients were determined at two ages, from 38 to 41 and from 56 to 59 d old, and caecal traits were recorded after slaughtering. In the <em>in vitro</em> trial, the five experimental diets were incubated with a rabbit caecal inoculum. Gas production was measured and modelled until 72 h and the fermentation traits were measured. Apparent faecal digestibility coefficients of main nutrients and main caecal environment traits were not significantly affected by the dietary inclusion of FSG (<em>P</em>&gt;0.05). However, animals fed with FSG showed lower caecal pH (–0.15; <em>P</em>&lt;0.05) values. Regarding the in vitro fermentation, FSG100 increased asymptotic gas production (+11.25, <em>P</em>&lt;0.001), sharpness of the switching characteristic of the profile (+1.98, <em>P</em>&lt;0.001) and the maximum substrate degradation rate (RM) (+0.188, <em>P</em>&lt;0.001), but decreasing the time after incubation at which half of the asymptotic amount of gas has been formed (–5.86, <em>P</em>&lt;0.001) and at which RM occurs (–4.53, <em>P</em>&lt;0.01). Likewise, FSG100 significantly decreased caecal pH (–1.035, <em>P</em>&lt;0.001), lactic acid (–9.51, <em>P</em>&lt;0.069) and N-NH₃ concentrations (–12.81, <em>P</em>&lt;0.001). Meanwhile, it increased the total volatile fatty acids (VFA) production (+43.15, <em>P</em>&lt;0.001). Gradual dietary inclusion of FSG from 0 to 0.5% only significantly increased total VFA production in the caecum (+100 mmol/L per percentage point of FSG inclusion; <em>P</em>&lt;0.05). In conclusion, FSG is highly and rapidly in vitro fermented by rabbit caecal bacteria. However, dietary inclusion of FSG up to 0.5%, might be insufficient to affect the apparent digestibility and fermentation profile of growing rabbits to a great extent.</p>

This thesis tackles the possible characterisation and utilisation of fenugreek (Trigonella foenum-graecum) seed gum (FSG) in the nutrition of young rabbits during the post-weaning period as an alternative to antimicrobials uses. The study was focussed on the behaviour of the extracted gum with different dietary fibre levels, both in vitro and in vivo.In a first trial, starting from a basal commercial rabbit diet, three experimental diets were formulated with gradual levels of inclusion of FSG (0, 0.25, 0.50 %)given to three groups of rabbits starting from weaning at 31 days old to slaughter 94 days old. The effect of the experimental diets was studied on the faecal