ABSTRACT The objective of this study was to review the effect of ensiling on the feeding value of flint corn grain and performance of feedlot cattle. In this meta-analysis, ensiled corn grain included both high-moisture corn and rehydrated corn grain. The criteria for a publication enter in the database were: diet was offered as a total mixed ration, diet contained at least 300 g/kg dry matter (DM) of ensiled or dry corn grain, and ensiled grain contained a minimum of 280 g/kg of moisture. The final dataset included 21 paired comparisons from eight publications, from 2002 to 2019. A sub dataset of digestibility trials contained six paired comparisons for starch digestibility and five paired comparisons for DM digestibility. The outcomes were compared using the Mixed procedure of SAS, including a random effect of comparison within study (paired comparison). Ensiling corn grain increased total-tract digestibility of DM (+4.59%) and starch (+3.33%), decreased DM intake by 14.1% (10.3 and 8.85 kg/d for dry and ensiled, respectively) and metabolizable energy intake by 4.39%, but did not affect average daily gain (1.61 and 1.58 kg/d for dry and ensiled corn, respectively). Therefore, ensiling corn grain increased feed efficiency by 18.3% (0.164 and 0.194, for dry and ensiled, respectively). The feeding value was on average 25.7% higher for ensiled corn grain compared with dry corn grain. Ensiling is an efficient strategy to improve the caloric value of flint corn grain for finishing cattle.

ABSTRACT The objective was to evaluate the effects of corn silage supplemented with 1-propanol or inoculated with L. buchneri on the ruminal fermentation profile, digestibility, and production traits of lactating Holstein cows. Whole-corn plants were harvested at 350 g/kg dry matter (DM) and packed in nine bag silos (13 t/silo). At ensiling, two treatments were applied: control (no additive; six silos) and L. buchneri inoculation with 1 × 105 cfu/g (three silos). Feeding started after 247 days of storage; one L. buchneri and two control silos were opened in each experimental period. Twenty-one multiparous Holstein cows (~33 kg/day of milk) were allocated to seven balanced 3 × 3 Latin squares with 21-day periods (14 days of adaptation). The experimental diets contained (DM basis): 80 g/kg cottonseed, 95 g/kg citrus pulp, 180 g/kg soybean meal, 90 g/kg corn grain (ground), 25 g/kg minerals and vitamins premix, and 530 g/kg of corn silage. Source of corn silage was the only difference between experimental treatments: control, L. buchneri, or control silage supplemented with 1-propanol (10 g/kg of diet DM). The 1-propanol was dissolved in water (1:1) and sprinkled onto the ration during mixing, immediately before each feeding. Dry matter intake, nutrient digestibility, milk yield, and composition were not affected by treatments. Cows fed 1-propanol had greater concentrations of 1-propanol in the rumen fluid, higher concentration of glucose, and lower concentration of non-esterified fatty acids in blood plasma. Corn silage inoculated with L. buchneri at 1 × 105 cfu/g does not affect silage fermentation, ruminal fermentation profile, or milk production. Supplementation of 1-propanol at 10 g/kg affects the ruminal fermentation profile without affecting feed intake and milk production of mid-lactating dairy cows.