Variation i torrsubstanshalt mellan balar från samma vallfoderparti och dess påverkan på utfodring

Abstract: Horses are adapted to eat grass and require sufficient amounts of forage with good hygienic quality. Forage with good hygienic quality have low levels of detrimental bacteria, fungi and toxins. For this reason, conserved grass such as hay, silage or haylage is necessary during the winter period, due to the absence of fresh grass. If horses are fed too low amounts of forage, there is a risk of development of stereotypic behaviour and digestive problems. The recommended minimum forage amount for horses is 1 kg dry matter per 100 kg bodyweight and day. Therefore, it is important to know the dry matter content of the forage, to be able to calculate the amount of forage that should be given to the horse. It is common to feed overweight horses the minimum recommended amount of forage, and it is also known that the dry matter content varies in silage and haylage bales harvested from the same field. Large variation in dry matter content between bales can lead to horses not getting sufficient amounts of forage or highly various forage dry matter amounts from day to day. The aim of this study was to investigate the variation in dry matter content between bales from the same harvest batch and its potential impact on horse feeding. Nineteen bales from the same batch were used, and each bale was sampled at eight different sites. The method for taking the samples was grab samples. To determine the dry matter content in each forage sample, the samples were weighed and dried in a microwave oven until no further weight loss was observed. The results of this study showed that there were differences in dry matter content between bales harvested from the same field at the same time. Some bales showed a large variation in dry matter content depending on where the samples were taken. It is unclear whether this was due to the composition of the bale or the analytical procedure. The variation in dry matter content can lead to overfeeding or underfeeding. If the horses are overfed, there is a risk of obesity and extra costs for the horse owners. If the horses are underfed, there is a risk of nutrition deficiency and too low amount of forage which may contribute to development of stereotypic behaviours in the long run. To ensure that the horses get adequate forage amounts, it is important to continuously examine the forage dry matter content.