The aim of this work was to conduct the effects of cricket (Gryllus bimaculatus) meal (CM) as a protein supplement on in vitro gas production, rumen fermentation, and methane (CH₄) mitigation. Dietary treatments were randomly assigned using a completely randomized design (CRD) with a 2 × 5 factorial arrangement. The first factor was two ratios of roughage to concentrate (R:C at 60:40 and 40:60), and the second factor was the level of CM to replace soybean meal (SBM) in a concentrate ratio at 100:0, 75:25, 50:50, 25:75, and 0:100, respectively. It was found that in vitro DM degradability and the concentration of propionic (C₃) were significantly increased (p < 0.05), while the potential extent of gas production (a + b), acetate (C₂), acetate and propionate (C₂:C₃) ratio, and protozoal population were reduced (p < 0.05) by lowering the R:C ratio and the replacement of SBM by CM. In addition, rumen CH₄ production was mitigated (p < 0.05) with increasing levels of CM for SBM. In this study, CM has the potential to improve rumen fermentation by enhancing C₃ concentration and DM degradability, reduced methane production, and C₂:C₃ ratio. The effects were more pronounced (p < 0.05) at low levels of roughage.

This experiment was conducted to assess the effect of Chaya (Cnidoscolus aconitifolius) leaf pellet (CHYP) on rumen fermentation, nutrients digestibility and microbial protein synthesis in growing crossbred bulls. Four animals, with an average liveweight of 160 ± 10 kg were randomly arranged in a 4 × 4 Latin square design. There were four treatments: 0, 4, 6 and 8% CHYP supplementation of DMI. The study findings showed that increasing supplementation level of CHYP linearly enhanced (p < 0.05) DM, OM, and CP digestibilities. Rumen characteristics, namely NH₃–N concentration and bacterial population were increased (p < 0.05) while, protozoal and fungal population remained unchanged, as level of CHYP supplementation increased. Total rumen volatile fatty acids (VFA) and propionic acid (C₃) were enhanced (p < 0.05). Furthermore, N utilisation especially N absorption, N retention and efficiency of microbial nitrogen synthesis (EMNS) were significantly improved by increasing level of CHYP supplementation. Hence, CHYP supplementation is highly promising for ruminant feeding.

Objective: This study aimed at studying the potential use of Flemingia (Flemingia macrophylla) as a protein source fodder to improve nutrients digestibility and ruminal fermentation efficiency in beef cattle.Methods: Four, Thai native beef cattle were randomly assigned in a 4×4 Latin square design. Four levels of Flemingia hay meal (FHM) were used to replace soybean meal (SBM) in the concentrate mixtures in four dietary treatments replacing levels at 0%, 30%, 60%, and 100% of SBM.Results: The experimental findings revealed that replacements did not effect on intake of rice straw, concentrate and total dry matter (DM) intake (p>0.05). However, the apparent digestibilities of DM, organic matter, crude protein, acid detergent fiber, and neutral detergent fiber were linearly increased up to 100% replacement levels. Moreover, the production of total volatile fatty acids, and propionate concentration were enhanced (p<0.05) whereas the concentration of acetate was reduced in all replacement groups. Consequently, the CH4 production was significantly lower when increasing levels of FHM for SBM (p<0.05). Furthermore, rumen bacterial population was additionally increased (p<0.05) while protozoal population was clearly decreased (p<0.05) in all replacement groups up to 100%. In addition, microbial nitrogen supply and efficiency of microbial nitrogen synthesis were enhanced (p<0.05), as affected by FHM replacements.Conclusion: The findings under this experiment suggest that 100% FHM replacement in concentrate mixture enhanced rumen fermentation efficiency, nutrients digestibilities, bacterial population, microbial protein synthesis, and subsequently reduced CH4 production in beef cattle fed on rice straw.