In situ techniques to predict in vivo digestibility and to evaluate the impact of flint maize processing methods on degradation parameters

Abstract

This study aimed to (1) evaluate the effects of flint maize processing methods on the estimation of the readily soluble fraction (a), the potentially degradable fraction (b) and the rate of degradation of b (c) for dry matter (DM), organic matter (OM) and starch in the rumen; and (2) verify whether two different applications of in situ technique can be used to estimate in vivo DM, OM and starch digestibilities. Five ruminally cannulated Nellore bulls (265 ± 18.2 kg; 8 ± 1.0 mo) were distributed in a 5 × 5 Latin square. Three experimental diets were composed of 0.30 whole-plant maize silage, 0.10 supplement and 0.60 of one of the following processing methods: dry ground maize grain (DMG); high-moisture maize (HMM); reconstituted maize grain silage (RMG). Two additional diets were composed of 0.10 supplement, 0.80 snaplage and 0.10 stalklage (SNAP-80); or 0.10 supplement and 0.90 snaplage (SNAP-90). Digestibilities were estimated using in vivo procedure or predicted from in situ technique using a single 24 h incubation point or an equation proposed in previous literature. Diets based on ensiled grains presented greater (P < 0.05) fraction a and c and lower (P < 0.05) fraction b of DM, OM and starch compared to DMG. Both alternative use of in situ technique accurately estimated (P > 0.05) in vivo DM, OM and starch digestibilities. The results suggest that ensilage process may increase the availability of nutrients. The two different applications of in situ technique showed precision and accuracy to estimate in vivo digestibility.

Ruminal responses, digestibility, and blood parameters of beef cattle fed diets without forage with different hybrids and processing of the corn

“…In our study, N‐NH 3 was least for steers fed high moisture, semi‐dent corn, and it decreased 1 h (i.e., peak) after the feed delivery. According to Godoi et al (2020), the ensilage process may increase the availability of nutrients. Thus, will occur synchronization between starch and protein degradation and the N‐NH 3 can decrease because to bettering utilization in the rumen environment by microbial synthesis.…”

Influence of crude protein content and flint maize processing methods on the performance of early-weaning Nellore calves

“…Some studies (Akins and Shaver, 2014; Ferraretto et al ., 2018; Bernardes and Castro, 2019; Godoi et al ., 2021 a , 2021 b ) have reported an improvement in starch digestibility when maize is harvested, stored and fed as snaplage. However, many factors may interfere with the digestibility of starch in diets based on grain silages, such as the moisture content at harvest time and ensiling (Owens et al ., 1997; Lardy and Anderson, 2016), particle size (Rémond et al ., 2004; Lardy and Anderson, 2016) as well as the length of storage time (Hoffman et al ., 2011).…”

“…The use of a forage harvester fitted with a maize snapper header and an on-board grain processor allows simultaneous harvesting and chopping of snaplage components (Lardy and Anderson, 2016; Ferraretto et al ., 2018). Also, snaplage is considered a high-energy feed product (Lardy and Anderson, 2016) that could be used as an exclusive fibre and energy source in feedlot diets or in combination with other feeds (Godoi et al ., 2021 b ). Therefore, diet formulation using snaplage will vary according to the harvest methods and desired performance.…”