A comparison of different legume seeds as protein supplement to optimise the use of low quality forages by ruminants

Field pea can replace soybean meal-corn mixtures in the fattening concentrate of young bulls improving the digestibility

The inclusion of pea (Pisum sativum) in the fattening concentrate at 0%, 15%, 30%, and 45% as a replacement for soybean meal and corn was evaluated on in vitro and in vivo digestibility studies of young Parda de Montaña bulls. In the in vitro trial, gas production was determined with an Ankom system for 48 h. The 30%pea and 45%pea concentrates increased the organic matter (OM) degradability, the ammonia-N content and the ratio of acetic:propionic, with no effect on gas production, final ruminal pH and total volatile fatty acid production. In the in vivo assay, 4 young bulls (initial weight 251 ± 4 kg) received restricted amounts of concentrates plus straw during 4 consecutive experimental periods. No differences in intake were observed and 30%pea and 45%pea had higher digestibility of crude protein (CP), and OM than the rest of treatments. The nitrogen intake increased linearly with the inclusion of pea with similar nitrogen urinary and faecal excretions, and the nitrogen retained was greater in 30%pea and 45%pea than the rest of treatments. The plasma concentrations of IGF-1, total protein, β-hydroxybutyrate and urea at the beginning and at the end of each period were not affected by the inclusion of pea. In conclusion, the total replacement of soybean-corn mixtures by pea in the fattening concentrate of bulls could be recommended as it improved the CP digestibility and nitrogen retention.

The effect of the inclusion of pea in lamb fattening concentrate on in vitro and in situ rumen fermentation

BACKGROUND

The objective of this study was to evaluate the effect of the proportion of pea (0%, 10%, 20%, and 30%), as a partial replacement for soybean meal (SBM) in the fattening concentrate, on ruminal fermentation in lambs. Gas and methane (CH4 ) production, in vitro dry matter degradability (IVDMD), ammonia (NH3 -N), and volatile fatty acid (VFA) production after 24 h of incubation were evaluated. The concentrates were also incubated in the rumen of the wethers for 2, 4, 6, 8, 12, and 24 h to evaluate the effects of pea inclusion on in situ dry matter degradability (DMD), organic matter degradability (OMD), nitrogen degradability (ND), NH3 -N, and VFA production.

RESULTS

In the in vitro assay, the inclusion of pea only affected gas production (mL day-1 degraded dry matter), CH4 production (mL day-1 degraded dry matter), and IVDMD (P < 0.05), and tended to affect NH3 -N content (P < 0.10) without affecting VFA production. In the in situ assay, the inclusion of pea increased DMD, OMD, and ND linearly (P < 0.001), whereas pea inclusion decreased NH3 -N content linearly (P < 0.05). Neither total VFA production nor the proportion of acetic acid were affected by pea inclusion (P > 0.05), but the propionic proportion increased with the proportion of pea included.

CONCLUSIONS

The best level of pea inclusion in the concentrate could not be established based on the results of this study. However, the results showed that the inclusion of pea provides a good alternative protein source. © 2020 Society of Chemical Industry.

Effects of Branched-chain Amino Acids on In vitro Ruminal Fermentation of Wheat Straw

This study investigates the effects of three branched-chain amino acids (BCAA; valine, leucine, and isoleucine) on the in vitro ruminal fermentation of wheat straw using batch cultures of mixed ruminal microorganisms. BCAA were added to the buffered ruminal fluid at a concentration of 0, 2, 4, 7, or 10 mmol/L. After 72 h of anaerobic incubation, pH, volatile fatty acids (VFA), and ammonia nitrogen (NH3-N) in the ruminal fluid were determined. Dry matter (DM) and neutral detergent fiber (NDF) degradability were calculated after determining the DM and NDF in the original material and in the residue after incubation. The addition of valine, leucine, or isoleucine increased the total VFA yields (p≤0.001). However, the total VFA yields did not increase with the increase of BCAA supplement level. Total branched-chain VFA yields linearly increased as the supplemental amount of BCAA increased (p<0.001). The molar proportions of acetate and propionate decreased, whereas that of butyrate increased with the addition of valine and isoleucine (p<0.05). Moreover, the proportions of propionate and butyrate decreased (p<0.01) with the addition of leucine. Meanwhile, the molar proportions of isobutyrate were increased and linearly decreased (p<0.001) by valine and leucine, respectively. The addition of leucine or isoleucine resulted in a linear (p<0.001) increase in the molar proportions of isovalerate. The degradability of NDF achieved the maximum when valine or isoleucine was added at 2 mmol/L. The results suggest that low concentrations of BCAA (2 mmol/L) allow more efficient regulation of ruminal fermentation in vitro, as indicated by higher VFA yield and NDF degradability. Therefore, the optimum initial dose of BCAA for in vitro ruminal fermentation is 2 mmol/L.

Protein and amino acid composition of select wild legume species of tribe Fabeae

The nutritional characteristics of seed proteins of 50 Spanish wild taxa of Lathyrus, Lens, Pisum and Vicia have been compared. The highest average protein richness and the in vitro protein digestibility have been observed in the genus Vicia and Lens, respectively, whereas the genus Pisum showed the lowest protein-digestibility corrected amino acid score. Using the K-means algorithm three clearly distinguished groups of taxa have been established in relation to their essential amino acid contents, protein richness, digestibility and nutritional parameters. The most adequate protein profile was observed in the taxa of group 1. This group includes four taxa of genus Lathyrus and nine taxa of genus Vicia. It should be noted that seven of the thirteen taxa included in this group have never been used as crops.