Post digestion weed seed survival in cattle

Incubation time evidenced the greatest impact on seed germination and viability (6 species), where diet (4 species) and Incubation time x diet interaction (3 species) had lower impact. Compared to the control, <i>A. theophrasti</i> germination increased to 150% after 12 h but dropped to ~20% after 48 h under the lactating cows' diet. Germination of <i>A. myosuroides</i> remained stable initially but fell to ~60% after 48 h, while <i>A. sterilis</i> showed consistently low germination, further declining with digestion. Germination of <i>C. album</i> rose to ~130% after 48 h, and the one of <i>E. crus-galli</i> to ~140%. For <i>D. stramonium</i>, germination decreased to ~20%, with heifers' diet causing greater losses. No significant effects were noted for <i>L. multiflorum</i>, <i>S. halepense</i>, or <i>A. retroflexus</i>. Viability losses were significant for <i>A. theophrasti</i> and <i>A. myosuroides</i> under the lactating cows' diet and for <i>D. stramonium</i> under the heifers' diet. Possible variation causes were evidenced in the thickness and the fibrous content (NDF, ADF, ADL) of the seed coats, correlated with the rumen microbial activity.