Exchanging physically effective neutral detergent fiber does not affect chewing activity and performance of late-lactation dairy cows fed corn and sugarcane silages

Abstract

The objective of this study was to determine whether replacing the physically effective neutral detergent fiber (peNDF) of corn silage with sugarcane silage peNDF would affect performance in dairy cows. Twenty-four late-lactation Holstein cows were assigned to eight 3 × 3 Latin squares with 21-d periods. The dietary treatments were (1) 25% peNDF of corn silage, (2) 25% peNDF of sugarcane silage, and (3) 12.5% peNDF of corn silage + 12.5% peNDF of sugarcane silage. The physical effectiveness factors (pef) were assumed to be 1 for corn silage and 1.2 for sugarcane silage, as measured previously by bioassay. Thus, peNDF was calculated as neutral detergent fiber (NDF) × pef. The concentrate ingredients were finely ground corn, soybean meal, pelleted citrus pulp, and mineral-vitamin premix. Dry matter intake (22.5 ± 0.63 kg/d), 3.5% fat-corrected milk yield (28.8 ± 1.13 kg/d), milk composition (fat, protein, lactose, urea, casein, free fatty acids, and somatic cell count), and blood metabolites (glucose, insulin, and nonesterified fatty acids) were unaffected by the treatments. The time spent eating, ruminating, or chewing was also similar among the diets, as was particle-sorting behavior. By contrast, chewing per kilogram of forage NDF intake was higher for the sugarcane silage (137 min/kg) than the corn silage diet (116 min/kg), indicating the greater physical effectiveness of sugarcane fiber. Based on chewing behavior (min/d), the estimated pef of sugarcane silage NDF were 1.28 in the corn silage plus sugarcane silage diet and 1.29 in the sugarcane silage diet. Formulating dairy rations of equal peNDF content allows similar performance if corn and sugarcane silages are exchanged.

Fibre digestibility and its relationships with chemical and morphological traits in thirty‐two sugarcane varieties

“…In addition to the digestion resistance, the arrangement of lignified tissues in C4‐grass stems, such as the formation of sclerenchyma ring in the stem cortex zone, further hinders particle breakdown (Wilson et al ., ; Wilson, ). It increases ruminal retention time and physical fill, which ultimately rationalize the higher physical effectiveness of sugarcane NDF (Sá neto et al ., ) and the lower DM intake of sugarcane‐based diets (Corrêa et al ., ; Oliveira et al ., ) compared with traditional forages (e.g. maize silage).…”

“…Sugarcane is financially competitive as a forage crop due to its high dry‐matter (DM) and sugar yields in tropical areas. Although high‐performing ruminants can be fed successfully with sugarcane (fresh or ensiled), it usually requires high levels of concentrate supplementation (Corrêa et al ., ; Queiroz et al ., ; Sá neto et al ., ) to avoid low‐feed intake (Costa et al ., ) caused by low neutral detergent fibre (NDF) digestibility (Andrade and Pereira, ; Oliveira et al ., ; Sousa et al ., ). Hence, selecting sugarcane varieties with lower NDF content and higher NDF digestibility might be a strategy to improve the efficiency of livestock production based on sugarcane.…”

Invited review: Current perspectives on eating and rumination activity in dairy cows

“…Forage fiber that is less digestible will lead to increased rumination time per kilogram of ingested DM and NDF. This can be seen in a study by Sá Neto et al (2014), who compared diets containing corn silage, sugarcane silage, and a mixture of the 2 forages. The FNDF content, pef, and MPS of the diets were relatively similar.…”

Production and utilization of silages in tropical areas with focus on Brazil

“…Compared to other crops, sugarcane NDFD is low (<350 g/kg; Oliveira et al., ), due to the higher proportion of indigestible NDF (~500 g/kg of NDF) and lower digestibility of the potentially digestible NDF (Daniel, Capelesso, et al., ; Daniel et al., ). Sugarcane fibre tends to have a high ruminal retention time and physical fill capacity, which accounts for the high physical effectiveness of sugarcane NDF (Sá Neto et al., ) and low DM intake of sugarcane‐based diets (Correa et al., ; Oliveira et al., ).…”