The possibility of using plasma urea nitrogen concentration as a rapid and reliable indicator of amino acid requirements in pigs of different age, sex and genotype was discussed on the basis of literature review.
The effect of supplementing a pig diet containing grass silage with herbs’ mixture and enzymes on body weight gains and quality of carcass and meat was investigated on 64 fatteners originating from sows (PL × LWP) mated with a boar (Duroc × Pietrain). Group I received restricted amounts of feed mixture and ad libitum grass silage. Experimental groups received the same diet with various additives: group II - herbs’ mixture 5.0 kg/t of feed mixture; group III - enzymes (beta-glucanase 325 BGU/g - 200 g/t, xylanase 210 U/g - 200 g/t of feed mixture); group IV - herbs’ mixture together with enzymes. The obtained results indicated that supplementing pigs diet containing grass silage with fodder enzymes, especially enzymes combined with herbs, increased body weight gains of young pigs, during the first fattening period. The addition of herbs’ mixture to grass silage diet improved meat sensory traits and its water holding capacity index and reduced meat yellowness.
The results of studies on the use of prebiotic fructans in animal diets have been discussed in the article. The mechanism of beneficial effects of fructans in organism could be linked to their prebiotic properties, i.e. stimulation of intestinal growth of bifidobacteria. Results of animal experiments indicate that fructans can increase intestinal production of short-chain fatty acids, decrease intestinal pH and the production of fecal odors, stimulate mineral absorption and positively affect immune functions in pigs, poultry and rabbits.