Physical characteristics of feed collected from Italy and Serbia
The aim of this study was to investigate the physical quality of a selected lot of twenty animal feed samples collected in Italy and Serbia. Granulation of cattle and pig feed was finer in Italian than in Serbian samples. Flowability of samples from both countries in mash form were rated from fair to good (angle of repose >30°) while granulated samples (pellets and extrudates) had improved flowability (angle of repose <20°). Extruded products had higher hardness (>10 kg) than pelleted products (<8 kg). Durability of most of the extruded and pelleted products was higher than 95%. Generally, it was observed that most of the physical characteristics of the samples responded to recommendations, which showed that the similar practices are in use in both countries.
The industrial compound feed sector is a key segment in the agro–food sector in general and in the chain of food products of animal origin in particular. According to den Hartog (1), an important aspect of feed quality (besides nutritional quality, safety for animals, environment and consumers, and emotional quality) is technical quality, i.e. physical properties of compound feed. Physical properties of single ingredients and the resulting pre-mix and/or compound feeds play a significant role in their resulting storage and flow behaviour, and are therefore essential to design appropriate, efficient, and economic bulk solids handling and storage equipment and structures (2), which are able to guarantee a good final quality, and which will respond to animals’ preferences.
Important physical characteristic of feedstuffs within compound feed is particles size distribution. Goodband et al. (3) reported that particles size reduction increases the surface area per unit volume allowing greater access to digestive enzymes. Moreover, particles size reduction may affect handling and mixing of the ingredients (4). However, optimal particle size largel ...