Effects of lactic acid fermentation and gamma irradiation of barley on antinutrient contents and nutrient digestibility in mink (Mustela vison) with and without dietary enzyme supplement

Fermented Rapeseed Meal as a Component of the Mink Diet (Neovison vison) Modulating the Gastrointestinal Tract Microbiota

Fermented rapeseed meal (FRSM) was used in the diet of American mink (Neovison vison). An advantage of this product is its prebiotic and functional properties, which can modify the bacterial microbiota of the GIT. A control group and three experimental groups were formed, with 60 animals in each group. The control group received a basal diet and the experimental groups received a diet with a 2%, 4% or 6% of FRSM as a replacement of extruded wheat. Bacillus subtilis strain 87Y was used to ferment the rapeseed meal (RSM). The study was conducted on mink from the age of 16-17 weeks until slaughter. Changes in the microbiota were analysed in samples of the animals' faeces and intestinal contents. The analyses included determination of the total number of bacteria and fungi, the number of coliforms and Escherichia coli, the total number of anaerobic Clostridium perfringens, and the presence of Salmonella spp. In animals receiving 4% and 6% FRSM (groups II and III), the content of microscopic fungi and the number of C. perfringens bacteria was significantly (p ≤ 0.05) lower than in the animals from the control group (group 0). A decrease in E. coli was observed in all experimental groups (I, II and III), although these differences were not statistically significant. The inclusion of FRSM in the feed ration did not affect the number of lactic acid intestinal bacteria. Analysis of the results obtained from the stool samples showed that the inclusion of FRSM in the ration did not significantly affect the number of microorganisms in each group. However, as in the case of the intestinal contents, in these samples there was a decrease in the total number of C. perfringens in the experimental groups (I, II and III), with a simultaneous increase in the number of mesophilic bacteria in relation to the control. There was no detection of Salmonella bacteria in any of the analysed material.

Energy content and nutrient digestibility of diets containing Lactobacillus-fermented barley or wheat fed to weaned pigs

This study was conducted to determine the energy content and apparent total tract digestibility (ATTD) of nutrients of diets containing Lactobacillus-fermented barley or wheat fed to weaned pigs. Thirty-six weaned pigs (8.14 ± 0.65 kg of body weight) were randomly assigned to 1 of 6 diets in a completely randomized design to give 6 replicates per diet. Pigs were individually housed in metabolism crates to determine digestible energy and metabolizable energy contents. Net energy was also calculated from the average of 2 equations published by Noblet et al. (1994). Diets were fed at 2.5 times the maintenance energy requirement for 10 d of adaptation and 5 d of total but separate urine and fecal collection. Samples of barley or wheat were fermented for 90 d under anaerobic conditions with an inoculum of either homofermentative Lactobacillus plantarum (Homo) or heterofermentative L. buchneri (Hetero). Three diets were formulated based on either barley or wheat to consist of a control diet containing 42% unfermented grain and 2 diets containing either Homo-fermented or Hetero-fermented grain. Preplanned contrasts were used to evaluate the effects of the inclusion of fermented barley or wheat and to compare the effects of Homo-fermented with Hetero-fermented grains. Fermented wheat inclusion in a diet increased ATTD of gross energy and phosphorus, and retention of gross energy by 1.9%, 6.8%, and 6.3%, respectively. Also, fermented wheat diets had greater (P < 0.05) metabolizable energy content and tended to have greater (P ≤ 0.10) net energy content than unfermented wheat diets. However, inclusion of fermented barley did not increase nutrient and energy digestibility. Hetero-fermented diets contained greater (P < 0.05) digestible energy and net energy content (DM basis) than Homo-fermented diets. Pigs fed barley-based diets showed less (P < 0.05) ATTD of DM, nitrogen, and gross energy than those fed wheat-based diets. In conclusion, wheat fermented with Lactobacillus-inoculum can be beneficially substituted for unfermented wheat, improving the ATTD of nutrient and energy, nitrogen retention, and energy content. Also, Hetero-inoculum is preferable to Homo-inoculum for grain fermentation considering greater energy content in weaned pigs.

Nitrogen-corrected apparent metabolizable energy values of barley varies by treatment and species

The aim of this study was to evaluate the effects of two species of poultry (cockerel and Japanese quail), two levels of enzyme (0 and 0.5 g/kg), and 6 processing methods (control (C), gamma irradiation 25 (GI25), and 50 kGy (GI50), autoclaving (AU), fermentation without lactobacillus (F), and fermentation with lactobacillus (FL)) on the nitrogen-corrected apparent metabolizable energy (AMEn) of barley. In this experiment, each processing method was tested at two levels of enzyme (0 and 0.5 g/kg) in six replications with two cockerels or four quails per replication. The results showed that the AMEn values by barley processing methods were: C-11.45 and 12.27; GI25-11.50 and 11.30; GI50-11.49 and 11.29; AU-11.70 and 11.46; F-12.90 and 12.30; FL-1295 and 12.51 MJ/kg in cockerels and quails, respectively. The AMEn (11.49 MJ/kg) of enzyme 0 was significantly lower than that of enzyme 0.5 (12.35 MJ/kg). There was a significant difference in the AMEn of processed barley between cockerels and quails. In conclusion, the most effective processing method of barley for AMEn is fermentation with lactobacillus and enzyme.