Effect of the diet energy level on production performance of lambs

Abstract

Investigations were carried out on 60 suckling lambs (24 males and 36 female lambs) - R2 generation obtained by crossing Pirot Pramenka with Württemberg rams, divided into 3 groups. At the beginning of the trial lambs were 30 days old with average body mass of 15 kg. Animals were fed ad libitum alfalfa hay and iso-protein mixtures (16% total protein) with different energy content. Energy value of used mixtures was 7.29 (I), 7.71 (II) and 7.94 MJ NEM (III). Trial lasted 60 days. Following production parameters were monitored: body mass, average daily gain, feed and nutrient consumption and conversion, depending on the applied feeding treatment. Statistical processing of obtained data was carried out on PC, using variance analysis. Final body masses of lambs (age of 90 days) were: 29.81 kg (I), 31.19kg (II) and 29.86 kg (III). Average daily gain for entire fattening period according to treatments I: II: III was 0.280kg: 0.303kg: 0.277kg. Values of DM conversion (kg/kg) for trial groups I:II:III were 2.68: 2.58: 2.93. Utilization of energy (MJ/kg) in average was 19.45: 18.98: 21.64, whereas the conversion of total protein (g/kg) according to the same order of treatments was 481: 451: 514. Performed research has shown that certain advantage can be attributed to lambs fed fodder mixture II (16% of total protein and 7.71 MJ NME), considering that they have realized the highest gain and the lowest use of feed and nutrients as well as energy.

U radu su prikazani rezultati uticaja različitih nivoa energije obroka na prirast i iskorišćavanje hrane i hranljivih materija jagnjadi. Ogled je izveden na 3 grupe po 20 jagnjadi sisančadi genotipa pirotska pramenka x virtemberg, uzrasta 30 dana i prosečne telesne mase oko 15 kg. Tov je trajao 60 dana, do telesne mase oko 30 kg. Jagnjad su hranjena lucerkinim senom i izoproteinskim krmnim smešama (sa 16% proteina) ali sa različitim sadržajem energije: 7.29: 7.71: 7.94 MJ NEM. Obrada podataka je urađena pomoću PC računara primenom analize varijanse. Najveći dnevni prirast (303 g) ostvarila su jagnjad koja su konzumirala krmnu smešu energetske vrednosti 7.71 MJ NEM. Konverzija suve materije (g/kg) na tretmanima I, II i III je iznosila 2680, 2580 i 2930, energije (MJ NEM /kg): 19.45, 18.97 i 21.64 i ukupnih proteina (g/kg): 481, 450 i 514.