Phytosterol and stanol (or phytosterols) consumption reduces intestinal cholesterol absorption, leading to decreased blood LDL-cholesterol levels and lowered cardiovascular disease risk. However, other biological roles for plant sterols and stanols have also been proposed. The objective of this review is to critically examine results from recent research regarding the potential effects and mechanisms of action of phytosterols on forms of cancer. Considerable emerging evidence supports the inhibitory actions of phytosterols on lung, stomach, as well as ovarian and breast cancer. Phytosterols seem to act through multiple mechanisms of action, including inhibition of carcinogen production, cancer-cell growth, angiogenesis, invasion and metastasis, and through the promotion of apoptosis of cancerous cells. Phytosterol consumption may also increase the activity of antioxidant enzymes and thereby reduce oxidative stress. In addition to altering cell-membrane structure and function, phytosterols probably promote apoptosis by lowering blood cholesterol levels. Moreover, consumption of phytosterols by healthy humans at the recommended level of 2 g per day does not cause any major health risks. In summary, mounting evidence supports a role for phytosterols in protecting against cancer development. Hence, phytosterols could be incorporated in diet not only to lower the cardiovascular disease risk, but also to potentially prevent cancer development.

Sustained price increases for traditional cereal grain and protein meal feed commodities have forced the pork industry to consider the dietary inclusion of alternative feedstuffs. Crop seed may serve as feedstuffs but their demand as feedstock for human food, biofuel, and bioindustrial products has increased. Together with these products, coproducts such as distillers dried grains with solubles, wheat millrun, and canola meal are produced. As omnivores, pigs are ideally suited to convert these non-human-edible coproducts into high-quality food animal protein. Therefore, coproducts and other low-cost alternative feedstuffs such as pulses and oilseeds can be included in pig diets to reduce feed cost per metric ton of feed. However, inclusion of alternative feedstuffs in pig diets does not necessarily reduce feed cost per kilogram of gain. Therefore, the use of novel and existing feedstuffs in pig diets must be optimized following their characterization for energy and AA profile. Alternative feedstuffs generally have a high content of at least 1 of the following antinutritional factors (ANF): fiber, tannins, glucosinolates, and heat-labile trypsin inhibitors. Several methods can optimize nutrient use of pigs fed alternative feedstuffs by reducing effects of their ANF. These methods include 1) particle size reduction to increase nutrient digestibility, 2) dehulling or scarification to reduce tannin and fiber content of pulses and oilseeds, 3) air classification to create fractions that have a greater content of nutrients and lower content of ANF than the feedstock, 4) heat treatments such as extrusion, toasting, roasting, and micronization to reduce heat-labile ANF, 5) dietary supplementation with fiber-degrading enzymes or predigestion of fibrous feedstuffs or diets with fiber-degrading enzymes to increase dietary nutrient availability, and 6) formulation of diets based on bioavailable AA coefficients. In conclusion, the feeding of alternative ingredients may reduce feed cost per unit of pork produced provided that their price per unit NE or digestible lysine is less than that of the traditional feedstuffs and that negative effects of their ANF are controlled.

Two experiments were conducted to determine the nutritive value of expeller-extracted canola meal (EECM) for growing pigs. In Exp. 1, a total of 6 ileally cannulated barrows (average initial BW = 26.8 kg) were fed 3 diets in a replicated 3 x 3 Latin square design to determine the apparent and standardized ileal digestibility (SID) values of N and AA and the SID AA contents of EECM. The 3 diets were a cornstarch-based diet with either solvent-extracted canola meal (SECM) or EECM as the sole source of protein, and a low-casein cornstarch-based diet, which was used to estimate basal endogenous N and AA losses to determine the SID of N and AA. All 3 diets contained chromic oxide as an indigestible marker for determining nutrient digestibility by the indicator method. In Exp. 2, a total of 18 intact barrows (average initial BW = 25.9 kg) were fed 3 diets in a completely randomized design (6 pigs per diet) to determine apparent total tract digestibility and retention of nutrients and the DE and ME contents of EECM. The diets were a basal corn-based diet or the basal diet with corn replaced by 35% SECM or EECM. The basal diet was used for determining the total tract digestible nutrient content by the difference method. Solvent-extracted canola meal, which is commonly used in the formulation of swine diets, was fed in both experiments for comparison with EECM. The SECM and EECM were similar in CP content (41.8 vs. 41.4%). Expeller-extracted canola meal was, however, greater in ether extract content (12.03 vs. 5.54%) and decreased in NDF content (23.8 vs. 29.9%) compared with SECM. The EECM also had a greater content of all the AA except Met, Cys, and Ser, by approximately 6.6%; Cys was greater in SECM, whereas Met and Ser were similar between the 2 meals. The EECM had greater (P < 0.05) SID of N, Arg, Ile, Leu, Phe, Glu, and Pro. The SID contents of Arg, His, Ile, Leu, Phe, Val, Ala, Asp, Glu, Gly, Pro, and Tyr were also greater (P < 0.05) for EECM than for SECM by an average of 15%. The EECM had greater (P < 0.01) DE (4,107 vs. 3,790 kcal/kg) and ME (3,978 vs. 3,564 kcal/kg) values compared with SECM. The results show that the EECM used in the current study had greater digestible AA and energy and a greater ME content than the SECM; hence, it may be a better source of protein and energy for growing pigs than SECM.

Woyengo, T. A. and Nyachoti, C. M. 2011. Review: Supplementation of phytase and carbohydrases to diets for poultry. Can. J. Anim. Sci. 91: 177–192. Feedstuffs of plant origin contain anti-nutritional factors such as phytic acid (PA) and non-starch polysaccharides (NSP), which limit nutrient utilization in poultry. Phytic acid contains phosphorus, which is poorly digested by poultry, and has the capacity to bind to and reduce the utilisation of other nutrients, whereas NSP are indigestible and have the capacity to reduce nutrient utilisation by encapsulation. Supplemental phytase and NSP-degrading enzymes (carbohydrases) can, respectively, hydrolyze PA and NSP, alleviating the negative effects of these anti-nutritional factors. In feedstuffs of plant origin, PA is located within the cells, whereas NSP are located in cell walls, and hence it has been hypothesized that phytase and carbohydrases can act synergistically in improving nutrient utilization because the carbohydrases can hydrolyze the NSP in cell walls to increase the accessibility of phytase to PA. However, the response to supplementation of a combination of these enzymes is variable and dependent on several factors, including the type of carbohydrase supplement used, dietary NSP composition, calcium and non-phytate phosphorus contents, and endogenous phytase activity. These factors are discussed, and areas that need further research for optimising the use of a combination of phytase and carbohydrases in poultry diets are suggested.

Three experiments were conducted to evaluate the effect of supplementing phytase and xylanase on nutrient digestibility and performance of growing pigs fed wheat-based diets. In Exp. 1, 10 diets were fed to 60 pigs from 20 to 60 kg of BW to determine the effect of combining phytase and xylanase on apparent total tract digestibility (ATTD) of nutrients and growth performance. The 10 diets included a positive control diet (PC; 0.23% available P; 0.60% Ca) and a negative control diet (NC; 0.16% available P; 0.50% Ca) supplemented with phytase at 0, 250, and 500 fytase units (FTU)/kg and xylanase at 0, 2,000, and 4,000 xylanase units (XU)/kg in a 3 x 3 factorial arrangement. In Exp. 2, 6 ileally cannulated barrows (initial BW = 35.1 kg) were fed 4 wheat-based diets in a 4 x 4 Latin square design, with 2 added columns to determine the effect of combining phytase and xylanase on apparent ileal digestibility (AID) of nutrients. The 4 diets were NC (same as that used in Exp. 1) or NC supplemented with phytase at 500 FTU/kg, xylanase at 4,000 XU/kg, or phytase at 500 FTU/kg plus xylanase at 4,000 XU/kg. In Exp. 3, 36 barrows (initial BW = 55.5 kg) were fed 4 diets based on prepelleted (at 80 degrees C) and crumpled wheat for 2 wk to determine the effect of phytase supplementation on ATTD of nutrients. The 4 diets fed were a PC (0.22% available P; 0.54% Ca) and a NC (0.13% available P; 0.43% Ca) alone or with phytase at 500 or 1,000 FTU/kg. All diets in the 3 experiments contained Cr(2)O(3) as an indigestible marker. No synergistic interactions were detected between phytase and xylanase on any of the response criteria measured in Exp. 1 or 2. There were no dietary effects on growth performance in Exp. 1. In Exp. 1, phytase at 250 FTU/kg increased the ATTD of P and Ca by 51 and 11% at 20 kg of BW or by 54 and 10% at 60 kg of BW, respectively, but increasing the level of phytase to 500 FTU/kg only increased (P < 0.05) ATTD of P at 20 kg of BW. In Exp. 2, phytase at 500 FTU/kg increased (P < 0.05) the AID of P and Ca by 21 and 12%, respectively. In Exp. 3, phytase at 500 FTU/kg improved (P < 0.05) ATTD of P by 36%, but had no further effect at 1,000 FTU/kg. Xylanase at 4,000 XU/kg improved (P < 0.05) AID of Lys, Leu, Phe, Thr, Gly, and Ser in Exp. 2. In conclusion, phytase and xylanase improved P and AA digestibilities, respectively, but no interaction between the 2 enzymes was noted.

An experiment was conducted to determine the standardized ileal digestible amino acid (AA) and AMEn contents of expeller-extracted canola meal (EECM) fed to broiler chicks. One hundred forty-four broiler chicks were divided into 24 groups of 6 birds balanced for BW and fed 4 diets in a completely randomized design (6 groups per diet) from d 14 to 21 of age. The diets were a corn-soybean meal-based basal diet formulated to meet NRC nutrient requirements, the basal diet with energy- and AA-yielding ingredients replaced by 30% of either solvent-extracted canola meal (SECM) or EECM, and a low-protein casein-cornstarch-based diet. The SECM, which is commonly used in formulating poultry diets, was fed for comparison with EECM, whereas the casein-cornstarch-based diet was fed to estimate basal endogenous AA losses for determining standardized ileal digestibility of AA. All 4 diets contained titanium oxide (0.3%) as an indigestible marker, and nutrient digestibility and retention were determined by the substitution method. From d 19 to 21, excreta samples were collected for AMEn determination. On d 21, the birds were killed by cervical dislocation, and contents of the whole ileum were obtained for determination of AA digestibility. Expeller-extracted canola meal had greater (P<0.05) standardized ileal digestible contents of Gly, Leu, Ser, Thr, Asp, and Glu and tended to have greater (P<0.10) standardized ileal digestible contents of Ile, Lys, Phe, Ala, and Tyr than SECM. Compared with SECM, EECM had greater (P<0.001) AMEn (2,694 vs. 1,801 kcal/kg). The results show that the EECM evaluated in the current study had greater standardized ileal digestible AA and AMEn contents than SECM, and hence, it may be a better source of protein and energy for broiler chicks than SECM. The standardized ileal digestible AA and AMEn values of EECM used in the current study could be used when formulating broiler chicken diets using the same to minimize the N excretion and feeding cost.

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A study was conducted to determine the effect of including expeller-extracted canola meal (EECM) in diets for broilers on performance, thyroid gland size, liver and kidney sizes, blood serum concentration of triiodothyronine and tetraiodothyronine, hemoglobin content in blood, hematocrit, and histology of liver and kidney. A total of 200 male broiler chicks (1 d old) were divided into 40 groups of 5 birds balanced for BW and fed 5 diets in a completely randomized design (8 groups/diet) from d 1 to 21 of age. The diets were a complete corn-soybean meal-based basal diet with 0, 10, 20, 30, or 40% of EECM. Diets were formulated to have the same ME, CP, Ca, nonphytate P, and standardized ileal digestible Met and Lys contents. The EECM contained (% of DM) 37.8% CP, 0.74% Met, 2.14% Lys, 1.62% Thr, 1.61% Val, and 7.64 μmol/g of glucosinolates. An increase in dietary level of EECM from 0 to 40% resulted in a linear decrease in feed intake (P < 0.001) by 4.8 g/21-d period for each 1% increase in EECM and in BW gain (P < 0.001) by 6.0 g/21-d period for each 1% increase in EECM. However, dietary EECM linearly increased liver weight relative to live BW (P < 0.001) and serum tetraiodothyronine concentration (P = 0.019). An increase in dietary level of EECM from 0 to 40% did not result in a significant increase in kidney weight relative to live BW. There was no effect of EECM on heart and thyroid gland weights relative to live BW or on the blood hemoglobin content, hematocrit, and serum triiodothyronine concentration. In conclusion, an increase in dietary level of EECM resulted in reduced growth performance and may interfere with liver function, likely because of increased dietary concentration of glucosinolates. Thus, the amount of EECM included in broiler diets should be based on the desired growth performance and the cost of the EECM.