Effects of silage made from primary or regrowth grass and protein supplementation on dairy cow performance

Evaluation of the factors affecting silage intake of dairy cows: a revision of the relative silage dry-matter intake index

“…in vitro pepsin cellulase method overestimates the regrowth silage D-value, unless separate correction equations are used for primary growth and regrowth grass material . However, also experimental data has proven that SDMI of regrowth silages has been lower than that of primary growth silages (Peoples and Gordon, 1989;Khalili et al, 2005;Kuoppala et al, 2005a). Since regrowth silage D-value was also lower in these studies, this was to be expected.…”

“…Positive associative effects of feeding mixtures of whole-crop and grass silages have been reported although the D-value of whole-crop silages have been lower than that of grass silages (Hameleers, 1998;Jaakkola et al, 2001 andPatterson and Kilpatrick, 2005). There is also evidence that cows consume less regrowth silages compared with primary growth silages (Peoples and Gordon, 1989;Khalili et al, 2005;Kuoppala et al, 2005a) but the comparisons of silage harvest have in most cases been confounded by variations in D-value, DM concentration and fermentation characteristics.…”

The effect of cutting time of grass silage in primary growth and regrowth and the interactions between silage quality and concentrate level on milk production of dairy cows

“…Practical experience and experimental results (Castle and Watson, 1970;Peoples and Gordon, 1989;Heikkilä et al, 1998;Khalili et al, 2005) have suggested inferior intake and production potential of RG silages compared to those made from PG. This effect may partly have been due to analytical problems as at least in vitro pepsin cellulase method overestimates the regrowth silage digestibility, unless separate correction equations are used for PG and RG grass material ( (Huhtanen et al, 2006a).…”

“…Further, in these studies the season (primary growth vs. regrowth) effects have often been confounded by differences in digestibility and silage fermentation characteristics. Castle and Watson (1970) and Khalili et al (2005) observed that silage intake and milk production were higher with silages made from the primary growth than from the regrowth of grass, but in both cases, regrowth silages were lower in digestibility. However, Peoples and Gordon (1989) and Heikkilä et al (1998) used regrowth grass silages of similar or higher digestibility than in primary growth and yet silage intake and milk production were higher when silage made from primary growth was fed.…”

Voluntary intake of silages in dairy cows depending on chemical composition and in vitro gas production characteristics

“…In this study no correlation was found between NDF and NDFD (Table 4). It has been suggested by Khalili et al (2005) that silages from primary growth of timothy give higher intake in dairy cows compared to silage from regrowth swards. This may explain the positive correlation between NDF and SDMI found in this study (Table 6) as NDF concentrations were higher in the primary growth swards.…”