The aim of this study was to investigate if the botanical composition of haylage affects pH, dry matter content and microbial composition of the faeces in horse and pig and ileal environment in pigs. Two separate studies were conducted where pigs and horses were fed two diets containing haylages with different botanical composition. The first haylage was from a tilled land dominated by timothy and meadow fescue and the other haylage came from a meadowland with a large inclusion of dandelion, 25 % and common couch. The dry matter content (70.8 % and 73.0 % respectively) and the pH-value (5.7) were similar in both feeds. The first study was made as a three-periods switch-back study with 7 Standardbred horses. In the first and the third period, 7 and 9 days long respectively, the diet consisted of the haylage from the tilled land, oats, sugar beet pulp, soy bean oil meal, lucerne pellets and brewers yeast.

Artificial insemination (AI) has had a great influence on the development of pig production and is today widely practiced (Gerrit et al., 2005). With AI, genetic progress can at a short period of time be spread worldwide compared with using natural service and the best boars can be intensively used. This is also one of the biggest risks with AI; the impact of semen containing a genetic disease or contamination of pathogens can be enormous. Fortunately, it is a small risk of disease transmission due to many tests of the boars and the semen before use (Maes et al, 2008). It is important that the boars used for insemination have good breeding values along with good reproduction features and have good fertility results (Robinson et al., 2005).

Artificial insemination (AI) has had a great influence on the development of pig production and is today widely practiced (Gerrit et al., 2005). With AI, genetic progress can at a short period of time be spread worldwide compared with using natural service and the best boars can be intensively used. This is also one of the biggest risks with AI; the impact of semen containing a genetic disease or contamination of pathogens can be enormous. Fortunately, it is a small risk of disease transmission due to many tests of the boars and the semen before use (Maes et al, 2008). It is important that the boars used for insemination have good breeding values along with good reproduction features and have good fertility results (Robinson et al., 2005).

Barren rearing environment and early weaning of piglets can lead to a high level of distress, behavioural disturbances and reduction in weight gain. The main aim of this thesis was to study the effects of potential enrichment objects on piglet?s behaviour and weight gain during the pre- and post-weaning period. The second aim was to examine what type of object stimulated the highest frequency of interaction. The study was carried out at the Swedish Livestock Research Centre in Lövsta where a batch of litters from 10 first-parity Yorkshire sows were used.