Open access publications in the SLU publication database

Abstract

Wrapped forages, in the form of silage and haylage, have become more common in horse diets during recent years. Silage and haylage is commonly produced in big bales. However, for use in stables with few animals, these bales often contain too much forage to be consumed before onset of aerobic deterioration. Smaller bales are therefore of interest, but knowledge of the chemical composition (including vitamin content), fermentation pattern and changes in those variables during storage of small bales is limited, and was therefore investigated. Small bale forage contained higher pH, higher ethanol and lower lactic acid content, compared to general levels in chopped silo silage, but low levels of ammonia-N and butyric acid. There were no general effects of dry matter or extent of fermentation on α-tocopherol and β-carotene contents in the preserved forages, but linear positive correlations between the vitamins and lactic acid existed. In general, long-term storage (14 months) of small bales influenced fermentation variables, yeasts and pH, but silage was affected by storage to a larger extent than haylage. Although changes occurred during storage, values in two month old bales correlated well with values obtained after 14 months. The influence of forage conservation methods on horse preference was also investigated. Hay, haylage and silage were produced from the same grass crops and the forages were offered simultaneously to horses. Silage was the first chosen forage, had the highest rate of consumption and the longest eating time, while hay had the lowest consumption rate and the shortest eating time. Haylage was intermediate between hay and silage in both eating time and rate of consumption. The influence of forage conservation methods on equine hindgut fermentation was studied using fistulated horses. Hay, haylage and silage were produced from the same grass crop and fed in a changeover study. Horses were sampled after being fed the forage for 21 days, and a kinetic study of colon fermentation was performed in each period. Forage conservation method had no effect on microbial or chemical composition in the right ventral colon or faeces on Day 21. All forages showed similar fermentation kinetics in the right ventral colon before (0h) and at 2, 4, 8 and 12 h after feeding.