Effects of dietary n-3 polyunsaturated fatty acids and ... - FINS

1 st WorkshopXIII International Feed Technology Symposiumthis reason the goal of organizing plant and animal production is not to bring allfactors of production to an optimum, because this is not possible, but to mutuallyharmonize all factors of production at an optimum, resulting in the best possibleresults of production under given conditions.During the last decade, production of maize for silage and maize for kernel is facinga very dangerous pest – Diabrotica virgifera, able to cause much damage in maizeproduction. The main measure to fight this pest is to avoid growing maize in repeatplanting, i.e. by growing maize in a planting sequence (4). One factor that veryfrequently appears in maize production in our country, and results in a huge decreaseof yield, is also draught. Under draught conditions maize had considerably loweryields, both of kernel and of the whole plant. As a consequence of this yielddecrease, very often in draught years many farms are not able to produce sufficientquantities of silage to feed cattle.In addition to adequate implementation of required agritechnical measures, one of theways to mitigate the consequences of draught on terrains not suitable for irrigation, isalso the introduction in plant production of cultures more resistant to draught than thepresently most used cultures in production. One such culture is sudan grass. Sudangrass can have very high yield of green mass, even above 120 t/ha (2), which is muchhigher than the yield of maize for silage, and this difference is especially pronouncedin draught years (5).From the aspect of plant production, sudan grass has many advantagesrecommending it for growing, and increasing its planting would not be disputable ifit were not for the fact that maize has certain characteristics placing it above othercultures from the aspect of animal feed production, and making it irreplaceable forsilage production. Above all, silage prepared from maize is much more easilydigested than sudan grass silage, i.e. the share of the fraction insoluble in neutraldetergent (NDF – hemicellulose, cellulose and lignin) is much lower in maize silagethan in sudan grass silage. From the aspect of cow nutrition, above data means thatwhole maize plant silage tastes good, and that cows more readily consume maizesilage, i.e. that they are able to consume more dry matter and energy from maizesilage than from sudan grass silage. The goal of this paper was to investigate thepossibility to replace maize silage with sudan grass silage under conditions ofintensive production in arid plant production. To answer this question, yield ofdigestible matter per surface unit was analyzed.MATERIALS AND METHODSMaize silage and sudan grass silage were produced for the needs of "Jadran" farm inCantavir, in 2003 and 2004. Both in 2003 and 2004, the strain NS Srem was plantedto prepare sudan grass silage. In production of sudan grass silage all technologicaloperations were implemented. Cutting and preparing sudan grass silage was donetwice a year, in the phase of ear formation. In 2003, plants were cut between 21 – 23July and 14 – 16 September, while in 2004 this was between 26 – 27 July and 11 –13 September.254