Effect of enzyme addition on the nutritive value of six lupin cultivars with different alkaloid content

An experiment was conducted to study the effect on chick performance of crude enzyme preparations when added to diets containing six different cultivars of lupin (Lupinus albus L.) seed grown in Canada. The lupin cultivars studied were Pnognus, NL, LAD, Hutterite, Amiga and Brandon. The total alkaloid content of these cultivars was 0.01, 0.02, 0.01, 0.04, 0.01 and 1.42%, respectively. The weight gain and feed consumption of the birds fed the high alkaloid content were reduced significantly (P < 0.0001; up to 43 and 31%, respectively) and the feed to gain ratio increased significantly (P < 0.0001; up to 21%) in comparison to the other cultivars. The addition of enzymes (0.1% each of Energex, Bio-Feed-Pro and Novozyme) increased signif icantly weight gain (P < 0.0033) and feed consumption (P<0.0116) by 5 and 1%, respectively, and reduced (P < 0.0055) feed to gain ratio by 4%. This was only seen in the low alkaloid cultivars. These results suggest that the enzyme addition improve the nutritional value of lupin cultivars with low content of alkaloid and that lupin alkaloids depress chick performance. Additional key words: bird nutrition, chicken, Lupinus albus.

have been reported by Roth Maier andKirchgessner (1994a,b, 1995), Annison et al. (1996), Ferraz de Oliveira (1998), and Brenes et al. (1993Brenes et al. ( , 2002)), while no effect or a negative effect has been reported by Alloui et al. (1994), Roth Maier and Kirchgessner (1995), Annison et al. (1996), andEder et al. (1996).The objective of this work was to analyse the total alkaloid content of six lupin seeds cultivars, and to determine the influence of lupin cultivars and enzyme additions to the diets on chick performance.
The Lupinus albus cultivars selected for this experiment were: Pnognus, NL, LAD, Amiga and Hutterite (they were grown in Saskatchewan, Canada), and Brandon (Manitoba, Canada).The crude enzyme preparation used in this study included: Energex (multienzyme complex that hydrolyses a broad range of carbohydrates produced from selected strain of Aspergillus niger), Bio-Feed Pro (proteolytic enzyme produced from selected strain of Bacillus licheniformis) and Novozyme SP-230 (alpha-galactosidase activity) from Novo Nordisk S.A., Denmark.The enzymes activities per gram crude product as determined by the manufacturers were as follows: Energex, 75 fungal β-glucanase units, 150,000 hemicellulase units, 10,000 pectinase units, and 400 endoglucanase units; Bio-Feed Pro, 150,000 protease units; Novozyme SP 230, 500 α-galactosidase units.The mixed crude enzyme preparation consisted of Energex, Bio-Feed Pro and Novozyme at 0.1% each.The different lupin cultivars were incorporated at a concentration of 50% in the diet.All diets were given in crumbles form and the birds had free access to water and feed throughout the entire experiment (1-3 weeks).The experimental diets were formulated to meet or exceed the minimum National Research Council (1994) requirements for Leghorn chickens.Chick performance was measured in terms of feed consumption, weight gain and feed to gain ratio.
Three hundred and sixty Leghorn chicks were purchased from a commercial hatchery and raised in Jamesway battery brooders for 7 days.All chicks were fed a commercial chick starter diet during the 7 days pre-experimental period.At 7 day of age, the birds were randomly distributed in Petersime battery brooders among 12 treatments using 6 birds per pen and 5 pens per treatment.The treatments were as follow: 1) Wheat-  (1967).The gas and thin-layer chromatography methods (Muzquiz et al., 1982(Muzquiz et al., , 1989) ) were used to respectively determine the total alkaloid content and their qualitative distribution in lupin cultivars (lupanine, isolupanine, 13-OH-lupanine and angustifoline).
The data (pen means) were subjected to analysis of variance using the General Linear Models (GLM) procedure of SAS ® software (SAS Institute, 1986).The experiment was analyzed by ANOVA in 6 (lupin cultivars) × 2 (enzyme concentration) factorial arrangements of treatments, and single df contrasts were used to separate treatment means in the factorial experiment.
The chemical composition and the amino acid content of the different cultivars of lupin seeds are presented in Table 2.A comparison of the gross composition of the six cultivars of lupin indicated differences among cultivars in percent protein, amino acids, ether extract, NDF, ADF, ash, calcium, phosphorus and manganese.The chemical composition shows good agreement with that quoted by Hill (1977) and Gdala and Buracewska (1996) for other L. albus cultivars.The variation in the crude protein content observed in the different cultivars studied was in agreement with the results reported by Petterson et al. (1997).The content of essential amino acids in lupin seed protein was found to be relatively balanced except for methionine which is low relative to the requirements of the growing chicks.The amino acid composition was similar to that reported by Hove (1974), Yule andMcBride (1976), andHill (1977).Among the different minerals, the most significant differences is reported in Mn content.These results confirm those showed by Hung et al. (1987Hung et al. ( , 1988)).In general, lupin tend to accumulate manganese when grown in acidic soils.Karunajeewa and Bartlett (1985) reported a manganese level in seed of L. albus cv.Hamburg grown in Victoria (Australia) that ranged from 900 to 3,920 mg kg -1 .The alkaloid content (Table 2) shows that five of the cultivars are low alkaloid lupins (Pnognus, NL, LAD, Hutterite and Amiga), with concentrations ranging from 0.01 to 0.04%.Brandon cultivar had the highest alkaloid content (1.42%).The dominant alkaloid in the Brandon cultivar was lupanine with 1.34%.Isolupanine, 13-OH-lupanine and angustifoline content were only detected in this cultivar.The concentrations of alkaloids in these cultivars are similar to those reported by Hill (1977) using L. albus cultivars.In general, the alkaloid content of the L. albus exhibits less variation within individual cultivars than L. angustifolius cultivars (Harris et al., 1986).
The performance data are presented in Table 3.The weight gain and feed consumption of the birds fed the high alkaloid content (Brandon cultivar) were reduced significantly (P < 0.0001; up to 43% and 31%, respectively) and feed to gain ratio increased significantly (P < 0.0001; up to 21%) in comparison to the other cultivars.The addition of the enzyme mixture to the diet increased weight gain (P < 0.0033) and feed consumption (P < 0.0116) by 5 and 1%, respectively, and reduced (P < 0.0055) feed to gain ratio by 4% only in the low alkaloid varieties.The results of the performance experiment demonstrated that Leghorn chicks fed a 50% of high alkaloid lupin diet performed poorly compared with those fed the low alkaloid lupin cultivars.This signif icant depression in chick performance was associated with a significant reduction in feed intake.The feed consumption was depressed up to 31% compared with the birds fed with low alkaloid content cultivars.Guillaume et al. (1979) found that alkaloids in bitter varieties of lupins depressed the appetite in chickens.In contrast, Buracewska et al. (1993) revealed no negative correlation between intake of the diets and their alkaloid content in chickens.This could be due to the use of a low content of alkaloids as they only incorporated 30% of lupin in the diet.In the current study the positive effect on the performance of birds fed enzymes in the low alkaloid cultivars has been previously demonstrated by Brenes et al. (1993Brenes et al. ( , 2002) ) using the Amiga cultivar in the diet.This effect has also been demonstrated by other authors (Annison et al., 1996;Ferraz Oliveira, 1998;Naveed et al., 1999) and corroborated by Kocher et al. (2000) and Brenes et al. (2002) that also showed that addition of a commercial enzyme preparation to a lupin-based diet resulted in a significant increase in the ileal digestibility of non-starch polysaccharides.
In conclusion, the results of the present study show that lupin cultivars with a high alkaloid content compared to those with a low alkaloid content are poorly utilized by chicks and that enzyme addition to diets with the white lupin low alkaloid cultivars improve their nutritional value.

Table 3 .
Effect of enzyme addition on the performance of Leghorn chicks (1-3 weeks) fed six lupin cultivars with different alkaloid content