Nutritional evaluation of two New Zealand cultivars of triticale (‘Aranui’ and ‘Karere’) using the rat, pig, and cockerel

Abstract

The nutritional value of two recently developed New Zealand cultivars of triticale, 'Aranui' and 'Karere', was determined by chemical analysis of the grain and by animal feeding studies. Four trials were carried out using rats to determine protein quality, apparent digestibility of protein and amino acids, apparent digestible energy (ADE) and apparent metabolisable energy (AME), and the capacity of triticale to support growth of rats followed by postmortem examination of the carcasses. Pigs were used to determine ADE and AME, and cockerels were used to determine true metabolisable energy (TME). Protein quality, as assessed by amino acid analysis (i.e., amino acid score) and determined by the rat bioassay procedure of relative protein value (RPV), was not different between cultivars. Rat ileal apparent digestibilities of amino acids were also not different between cultivars except for methionine and arginine. The ADE and AME bioassays using the rat and pig, and the TME bioassay using the cockerel, all showed a higher content of DE and ME in 'Karere'. 'Aranui' and 'Karere' supported similar rates of liveweight gain of rats given diets containing the same levels of crude protein. Postmortem examination of the carcasses showed no gross differences in the appearance of tissues and organs of rats fed triticale and control (lactalbumin) diets. The crude protein content of the two samples of triticale used in the evaluation was higher in 'Karere'. Five additional pairs of triticale samples from other localities showed a consistently higher level of crude protein in 'Karere'. From a nutritional standpoint, 'Karere' was the preferred cultivar because of a higher crude protein, DE, and ME content. The nutritional parameters determined with triticale were compared with corresponding literature or measured values for barley and bread wheat.

Partial and total replacement of barley by triticale in diets for growing pigs

“…These chemical determinations for 'Lasko' triticale and the barley grain source agree with previously reported values from New Zealand for these cereals (Department of Scientific and Industrial Research, Ministry of Agriculture and Fisheries 1979; James et al 1987). The crude protein contents Table 2 Detennined proximate analysis and amino acid content (g/kg air-dry weight) of the three triticale cultivars and barley included in the pig diets.…”

“…, 1989, Vol. 32 for 'Aranui' and 'Karere', however, were 16 and 26% lower respectively than found previously (James et al 1987) and this was reflected in their having lower amino acids levels. The current crude protein and amino acid levels for 'Aranui' and 'Karere' as found in this study were nevertheless within the range of values quoted in the literature for triticale grain (Villegas et al 1970;Radcliffe et al 1981;Farrell et al 1983).…”

“…Several of these workers suggested the presence of a trypsin inhibitor in the triticale grain as a possible cause of the depression in pig performance which resulted when triticale was the major or sole cereal grain in the diet. The triticale varieties' Aranui' and 'Karere' used in the present study have previously been shown (James et al 1987) to have low anti-trypsin activity (2-3 trypsin inhibitor units/g). The significance in pig growth depression however, remains purely speculative for it has not been firmly established that there is a causal relationship between trypsin inhibitor content of triticale and the relatively poor growth performance of animals fed on some varieties of the cereal.…”

“…Two New Zealand spring varieties oftritica1e namely 'Aranoi' and 'Karere' ,developedfrom lines selected from the CIMMYT breeding programme (James et al 1987) along with 'Lasko' , a Polish winter variety of triticale (Wolski 1986), and a locally grown barley were used in the study. The 'Aranui' (3.5 t) and 'Karere' (1.5 t) were grown on the same farm and the 'Lasko' (3.5 t) and barley grains (3.5 t) were purchased from a local merchant.…”

“…The chemical composition of triticale cultivars available locally for feeding to livestock (James et al 1987) indicates that nutritionally the grain could be competitive with barley and maize, the commonly used local cereals in pig and poUltry diets. In several overseas studies, however, the growth performance of pigs fed diets in which half or more of the cereal source was triticale, has been lower than anticipated from chemical analysis of the grain (Johnson et al 1983;Batterham 1986).…”