Analysis of the in situ digestibility growth of forage soybean varieties

Resumen

Objective: To evaluate the in situ digestibility during growth of four forage soybean (Glycine max L.) varieties in the dry tropics of Mexico. Design/Methodology/Approach: Four soybean varieties SalCer, Ojo de Tigre, Valente, and Albina were evaluated over an 82-day growth period. The variables measured included ash content, dry matter, and in situ digestibility. A completely randomized block design with three replicates per subplot was used. Mean comparisons among treatments were conducted using Tukey’s test at a significance level of α = 0.05. Results: The highest in situ digestibility was observed at 26 days of growth (68%), while the lowest occurred at day 54 (57%). On average, the Valente and Albina varieties exhibited the highest digestibility values, with 65% and 63%, respectively (p > 0.05). Limitations/Implications: Leguminous species enhance forage quality for ruminants in tropical systems, yet their use in animal feed remains limited. Forage soybeans represent a promising alternative due to their favorable nutritional characteristics. Findings/Conclusions: The Valente variety is recommended for forage use in the dry tropics, as it demonstrated superior and stable in situ digestibility. For optimal forage quality, cutting is advised after 68 days of growth, when dry matter content increases and ash concentration declines.