Effect of seasonal diet composition changes on the characteristics of the gastrointestinal tract contents of the Eurasian beaver (Castor fiber).

The goal of the study was to compare chemical and physical parameters of the content of various gastrointestinal (GI) tract segments of adult beavers and to relate the obtained results to seasonal changes in the composition of natural diet. The study was conducted on 36 adult beavers originated from the natural environment that were captured in winter, summer and autumn. The obtained results demonstrated that pH, redox potential (Eh), dry matter (DM), short-chain fatty acids (SCFA) and distribution of food particles varied along the beaver GI tract during the year. The lowest value of pH was observed in stomach whereas the highest in the small intestine and cecum. The reverse pattern of changes was found for the value of redox potential. The research indicated that anaerobic conditions were predominant in the cecum and so contributed to development of microbial population. Also, the increase in the SCFA contents in the cecum and colon indicated that beavers belong both to hindgut fermenters as well as to the mixed moderate type animals. In summary, the obtained results indicated that seasonal changes in the diet composition affected physical and chemical parameters as well as microbial activity of the GI tract of beaver

Influence of ingested forage on the composition of rumen microfauna in fallow deer

The aim of the study was to determine the correlation between ingested forage and composition of microfauna in the rumen of fallow deer. Rumen content of six specimens was obtained from the Bolimowska Forest during 2011/12 hunting season. Protozoa of the Entodinium and Epidinium genera belonging to the Ophryoscoleciade family were identified in analysed samples. Density of Entodinium population was positively correlated with percentage share of forage rich in starch. It was also reversely and equally strongly correlated to the share of forage rich in cellulose (p>0.05). Share of volume and biomass of Epidinium population was correlated negatively with the share of acorns in the forage (p>0.1). Differences in number and share of protozoa of the Entodinium and Epidinium genera in the rumen of fallow deer coexisting in the same place and time indicate feeding opportunism of this ruminant