TRITICALE (TRITICO-SECALE) AS SUBSTITUTE FOR MAIZE IN PIG DIETS

An experiment was conducted to quantify the effect of the inclusion of triticale (cv. Usgen 19) in the diets of pigs, on certain metabolism and production parameters. Three diets were formulated on an iso-nutri ent basis (approximately 13.9 MJ kg(-1) dry matter (DM) metabolizable energy, 17.2% crude protein, 1.00% lysine, 0.69% methionine and cystin e and 0.23% tryptophan on a DM basis) so that maize meal was substitut ed by increasing levels of triticale meal (0%, 33% and 67%). In a meta bolism and nitrogen (N) balance study with 18 SA Landrace x Great Whit e boars, DM digestibility, apparent N digestibility, digestible energy (DE) and metabolizable energy (ME) contents were largely independent of the substitution of maize by triticale. Apparent N retention tended (P less than or equal to 0.09) to be better on the triticale-containi ng diets. The diets were evaluated according to a 2 (sex) x 3 (diet) f actorial arrangement of treatments in terms of dry matter intake (DMI) , average daily gain (ADG) and feed conversion ratio (FCR), in a growt h study with 13 SA Landrace x Large White pigs per diet. Mean (+/- SE) initial live mass of the pigs was 23.4 +/- 0.3 kg. Pigs were fed ad l ibitum. The experiment ended when the pigs were slaughtered at a live mass of 90.6 +/- 0.2 kg, and carcass characteristics were determined. Daily DMI of pigs decreased linearly (P less than or equal to 0.01) by 198 (SE(b)= 71) g day(-1) per unit substitution of maize by triticale . Daily gain was similarly affected, with a corresponding linear (P le ss than or equal to 0.01) decline of 95 (SE(b)= 34) g day(-1). The sub stitution of maize with triticale up to 67% did not affect FCR signifi cantly; the mean FCR was 2.72 kg DMI required per kg live mass gain. M ean dressing percentage, eye muscle area or back fat thickness did not differ significantly between diets (means of 80.5%, 38.8 cm(2) and 17 .6 mm), although pigs on the 100% maize diet tended (P less than or eq ual to 0.07) to have thicker back fat than pigs on the triticale diets . Efficiency was thus largely unaffected by the substitution of maize by triticale. Triticale may therefore be used to substitute maize up t o 67% provided that the lower DMI and resultant poorer growth rate is taken into consideration.