Influence of mechanical processing of grains on digestibility of nutrients in sheep | Vplyv mechanickej úpravy jadrových krmív na stráviteľnosť živín u oviec

We investigated the effects of mechanical processing of grains on digestibility of nutrients and nitrogen balance in sheep. The basis of the diets was meadow hay supplemented with pea seed, barley grain and oat grain. The first diet contained whole pea, barley and oat (diet a). In the second diet we used whole pea, ground barley and ground oat (diet b) and in the third diet was pea, barley and oat grounded (diet c). The experiment was performed on six castrated male Cigaja sheep with mean live weight 43.2 kg. They had been castrated since about one month of age. Animals were fed twice a day - at 06.30 and 18.30. An 11-day adaptation period was followed by a 5-day experimental period. Diet samples were taken and analyzed for nutrient contents according to the Regulation of the Ministry of Agriculture of the Slovak Republic No. 2145/2004-100. During the experimental period feces and urine were collected. From the amounts collected per 24 hour average samples were taken for chemical analysis. Significance of differences between diets was evaluated by Fischers LSD test using the program Statgraphics, ver. 5.0. The lowest digestibility of dry matter (69%), crude protein (67%) crude fat (60%), crude fibre (54%), nitrogen free extract (77%) and organic matter (72%) was detected for diet a. Digestibility of the crude protein was the highest (78%) for diet c. In comparison with diet b the difference in digestibility of crude protein was 2% and it was not significant. No difference between diets b and c in the digestibility of starch, nitrogen free extract and crude fibre was detected. The highest number of feces nitrogen excretion was in diet a. It resulted in the lowest percentage of nitrogen intake retained and percentage digested nitrogen retained. Retention of nitrogen did not differ between diet b and c. Mechanical processing of pea seed minimally altered digestibility of nutrients and nitrogen balance.