Work

Growth performance and nutrient digestibility of beef heifers fed sorghum silage processed at harvest and stored for less than five months or over one year

Year: 2026

Type: article

Abstract: This study evaluated the effects of feeding sorghum silage (SS), either processed (PRO) or not (NPR) at harvest, on animal performance, apparent total tract digestibility (ATTD), and in situ nutrient degradability (ISND). The sorghum plant was harvested when the kernels were at the hard dough stage and kernel processing was applied or not prior to ensiling. Kernel processing was done with 110-tooth rolls, at 1.1 mm gap, and 50% speed differential, yielding a theoretical length of cut of 15 mm. On a dry matter (DM) basis, diets contained 90.5% SS, 6.5% soybean expeller, and 3% vitamin-mineral supplement. Performance and ATTD trials were conducted over two consecutive years using SS stored for < 150 days (Y1) or > 375 days (Y2). In situ nutrient digestibility was assessed on samples ensiled from 0 to 455 d. Animal performance studies were conducted using 96 Angus heifers each year in a completely randomized design with 6 pens (8 heifers/pen in both years), followed by an experiment to determine ATTD using one randomly selected heifer/pen at the end of each performance study. Data were analyzed as a completely randomized design using the Mixed procedure of SAS, with treatment as a fixed effect and initial body weight as covariate in the performance trials, and repeated measures in the ISND trial. In Y1, no differences in dry matter intake (DMI) were detected between treatments, but PRO improved final body weight and average daily gain (ADG; P < .02), as well as gain-to-feed ratio (P = .03). Apparent total tract digestibility of starch in Y1 was greater in PRO (P < .01), while no treatment effects were observed for NDF, ADF, or CP digestibility. In Y2, PRO increased DMI (P = .01), but ADG and feed efficiency were not different between treatments (P > .10). Nutrient intake and digestibility in Y2 were unaffected by treatments. For ISND, a treatment × day interaction was detected (P < .01) for DM degradability, where PRO increased DM degradability at d 66 and 202 of storage (P < .05). Starch degradability improved with storage time independently of processing. In conclusion, kernel processing of SS improved ADG by 15%, feed efficiency by 21%, and ATTD of starch by 8%, when compared to NPR in silage sored for < 150 d. However, processing did not provide any benefits when SS was stored > 375 days. Processing appears to enhance in situ DM degradability up to ∼300 days of storage, while starch degradability increased with storage time regardless of processing.

Source: Translational Animal Science

DOI: 10.1093/tas/txag028

Authors: Leandro O Abdelhadi, Guillermo A Mattioli, Fredric N Owens, Nicolás DiLorenzo

Institutions: University of Florida, Institute of Food and Agricultural Sciences, Universidad Nacional de La Plata, Oklahoma State University

Language: English

Topic: Ruminant Nutrition and Digestive Physiology

Subfield: Agronomy and Crop Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDG: Zero hunger

Open Access status: gold

Estimated APC paid: $3,308