The digestive physiology of terrestrial carnivorous mammals is characterised by a notable diversity among species. The occurrence of peculiar physiological and metabolic traits might find their origin in body size driven feeding strategies in the wild (Bosch et al., 2015). It has been well established that carnivore body size is a determining factor in the choice for a specific prey size with a switch from small to large prey feeding at a body mass treshold of ca. 20 kg (Carbone et al., 1999). Carnivore body size and the associated average prey size could further dictate a carnivore's feeding strategy. Reports in the literature describe large carnivores hunting prey larger than or similar to their own mass, typically ingesting large amounts of highly digestible food alternated with periods of famine (feast-and-famine adherents) (e.g. the wolf (Stahler et al., 2006; Bosch et al., 2015)); and, small carnivores that tend to specialize in prey with a lower mass than their own body weight that will typically ingest small, frequent meals in a non-selective way (e.g. wildcat (Bradshaw, 2006)). As such, it seems that carnivore body size drives a whole feeding strategy. However, the functional existence of both feeding strategies and their relation to carnivore body size has not been studied for a broad carnivore size spectrum (i.e. vertebrate-prey feeders) and could offer more insight in species diversification. Given the apparent difference in food intake, kill frequency and dietary composition between both feeding strategies, a difference in gut retention time can be expected. However, since gut retention can be affected by the physical structure of the diet (Ferguson and Harris, 1997; Carré, 2000) and since the majority of gastrointestinal passage studies in domestic carnivores and carnivores in captivity are conducted on traditional kibble diets or processed meats (Wyse et al., 2003; Boillat et al., 2010), gut retention time should be studied on whole prey diets (presence of physical structure) as a first step for future empirical relations of gut retention time and carnivore body size. Whole prey is characterised by more heterogeneity and structure and might affect gastrointestinal passage in ways that hitherto have been left unstudied.  
In general, this dissertation aims to elucidate how carnivore feeding strategies have co-evolved with carnivore digestive physiology: Does carnivore body size drive the choice for the 'frequentfeeding' strategy and 'feast-and-famine' strategy? How does digestive processing (focussed on gastrointestinal transit) occur on a whole prey diet?
First, the feature kill frequency, considered an important part of a feeding strategy,
will be modelled and scaled to carnivore body size. Kill frequency modelling will account for several carnivore as well as prey characteristics: carnivore size, prey size,
pack size, energetic requirements of carnivores, energy content in prey, gut capacity
and selective feeding. Carnivores will be labelled feast-and-famine or frequent-feeding
adherent based on the relationship prey size and gut capacity. The focus will be on vertebrate-prey feeding species given the different foraging strategies maintained by insectivorous and omnivorous species. The scaling of kill frequency with carnivore body size for both feeding strategies will render new information on the body size driven theory.
The second part of this dissertation aims to study  passage through the carnivore  gastrointestinal tract on a whole prey diet (varied in structure). The domestic dog (Canis  familiaris) will be studied as a carnivore species in order to unravel all components of  gastrointestinal passage (gastric emptying time, small bowel transit time, colonic  transit time and total transit time) and faecal characteristics (consistency and fermentation  profiles) on whole prey diets.