Tropical Plant Phytonutrient Improves the Use of Insect Protein for Ruminant Feed

This work aimed to examine the effects of binding proteins from <i>Gryllus bimaculatus</i> with <i>Sesbania grandiflora</i> phytonutrient on gas dynamics, in vitro digestibility, and ruminal fermentation characteristics. For rumen fluid sources, two dairy bulls with permanent cannulas were used as donors. <i>G. bimaculatus</i> and <i>S. grandiflora</i> powder were combined in the following ratios: 100:0, 99:1, 98:2, 97:3, 96:4, 95:5, 94:6, and 93:7. As 7% of <i>S. grandiflora</i> and 3% of <i>G. bimaculatus</i> were combined, the rumen undegradable protein increased by 45.8% when compared to the control group (<i>p</i> < 0.05). All gas kinetics were not substantially different across treatments, except for cumulative gas output during 96 h of incubation (<i>p</i> < 0.05). Comparing the <i>G. bimaculatus</i> powder to <i>S. grandiflora</i> at a ratio of 95:5 to 93:7 revealed an increase in cumulative gas production (<i>p</i> < 0.05), compared to the other groups. Reduction of <i>G. bimaculatus</i> resulted in a linear increase of in vitro dry matter digestibility (IVDMD) and in vitro organic matter digestibility (IVOMD) at 24 h after incubation. The lowest level of <i>G. bimaculatus</i>—93% with 7% <i>S. grandiflora</i>—showed the greatest IVDMD and IVOMD (<i>p</i> < 0.05) when compared with the control group. Ruminal pH in all treatments remained constant after 4 and 8 h of in vitro incubation (<i>p</i> > 0.05). However, as the quantity of <i>S. grandiflora</i> in the sample increased, the concentration of ammonia-nitrogen (NH₃-N) linearly decreased (<i>p</i> < 0.05). Compared to the control group, the NH₃-N concentration at 4 h of incubation was decreased by 47% when 7% <i>S. grandiflora</i> and 93% <i>G. bimaculatus</i> were mixed. The alteration in the <i>G. bimaculatus</i> to <i>S. grandiflora</i> ratio did not affect the levels of acetic acid or butyric acid. However, when 93% of <i>G. bimaculatus</i> was combined with 7% of <i>S. grandiflora</i> at hour 4 of incubation, propionic acid concentration was moderately increased (<i>p</i> < 0.01) by 6.58 mmol/L. In conclusion, combining 93% <i>G. bimaculatus</i> with 7% <i>S. grandiflora</i> powder enhanced protein utilization, in vitro digestibility, propionate concentration, and cumulative gas production.