Normal and hetero-yellow endosperm grain sorghum as substitute for maize in pig diets

Abstract

An experiment was conducted to evaluate a hetero-yellow endosperm sorghum cultivar (G766W) in comparison to a low-tannin (GL) sorghum cultivar as well as maize in a growth trial using pigs. The digestible energy (DE) content of the experimental diets as well as the grain components of these diets was determined by means of the mobile nylon bag technique (MNBT), while the chemical and amino acid compositions were determined by chemical analysis. There were no significant differences between the DE contents of the maize (16,1 MJ /kg DM), GL sorghum (16,6 MJ /kg DM) or G766W sorghum (16,0 MJ/kg DM) or the experimental diets (15,1, 15,2 and 15,3 MJ/kg DM respectively). The CP content (DM basis) of the diets varied between 19,9%, 20,6% and 21,2% for the maize, G766W sorghum and GL sorghum diets respectively, but the diets were almost equal in lysine (0,91, 0,96 and 0,91 %) and methionine plus cystine content (0,66, 0,61 and 0,58%). There were no significant differences in average daily gain and feed conversion ratio of pigs fed either maize, GL sorghum or G766W sorghum as the grain component in a balanced diet. It is therefore concluded that, provided that low-tannin grain sorghum of a good quality is used, and provided that the diet is composed to meet the recommended dietary levels, it is possible to optimize pig performance.

'n Eksperiment is uitgevoer om 'n hetrogeelendosperm-graansorghum (G766W) in vergelyking met 'n gewone laetannien( GL)-sorghum en mielies in 'n groeistudie met varke te evalueer. Die verteerbare-energie(VE)-inhoud van die eksperimentele diete sowel as die graankomponente van die diete is met behulp van die mobiele- kunsveselsakkietegniek (MNBT) bepaal, terwyl die chemiese- en  aminosuursamestelling deur chemiese analise bepaal is. Daar is geen betekenisvolle verskille in die VE-inhoud van die mielie- (16,1 MJ /kg DM), GL-sorghum- (16,6 MJ /kg DM) of G766W-sorghummonsters (16,0 MJ /kg DM), of in die VE-inhoud van die eksperimentele diete (onderskeidelik 15,1, 15,2 en 15,3 MJ/kg DM) gevind nie. Die ruproteien(RP)-inhoud (DM-basis) van die diete het gevarieer tussen 19,9%, 20,6% en 21,2% vir die mielies, G766W-sorghum en GL-sorghum onderskeidelik, alhoewel die diete byna gelyk in lisien- (0,91; 0,96 en 0,91%) en metionien-plus-sisteieninhoud(0,66; 0,61 en 0,58%) was. Geen betekenisvolle verskille in gemiddelde daaglikse toename en  voeromsettingsdoeltreffendheid van varke is tussen die diete gevind nie. Indien
lae-tanniengraansorghum van goeie kwaliteit dus gebruik word en die dieet volgens aanbevole vereistes saamgestel word, behoort geen probleme ondervind te word om optimum produksie te verkry nie.