Low Glucosinolate Rapeseed Meal Research Articles

Effects of high-moisture corn preserved with organic acids combined with rapeseed meal and peas on performance and gut microbiota activity of broiler chickens

The aim of the present study was to evaluate the interactive effects of the inclusion of wet corn grain preserved with organic acids (CP) and soybean meal (SBM) substitutes, including solvent-extracted low erucic acid, low glucosinolate rapeseed meal (RSM) and peas (PEA), in broiler diets. A total of 171 eight-day-old female Ross 308 broilers were distributed into 9 groups, each consisting of 19 birds kept in individual cages. During the 27-day feeding period, the birds received wheat-corn-SBM diets and were arranged in a 3 × 3 factorial design; the factors included corn treatments (CP, heat-dried corn moisture-reconstituted with water (CDW) or with preservative (CDP)) and three protein sources (SBM exclusively or mixed with RSM or PEA at the level of 150/200 g/kg diet). The feed intake and body weight gain declined in birds fed the RSM diet (P < 0.01), while corn treatments had no significant effects on the performance of the broilers. The RSM diets increased bacterial enzyme activity in the ileal and caecal digesta (P < 0.001) and decreased butyrate, acetate and total short-chain fatty acid (SCFA) concentrations in the caecal digesta (P < 0.001) compared with the values detected in the case of the SBM and PEA diets. Corn treatments had negligible effects on the bacterial enzyme activity of ileal and caecal microbiota but induced a decline in lactate concentrations in the ileum in the case of the diets with CP and CDP corn (P < 0.049). Our findings indicate that peas at the level of 150/200 g/kg are a good alternative to SBM, while diets with the same level of RSM may have an adverse effect on growth performance and acetate and butyrate production in the caecum. CP up to the level of 300 g/kg diet and peas can be used with no adverse effects on gut physiological status and the growth performance of broilers and provide an opportunity to include locally available grains in poultry rations.

Replacement of groundnut cake with low-glucosinolate rapeseed meal on performance, nutrient utilization, immunocompetence and carcass characteristics in lambs

Replacement of groundnut cake with low-glucosinolate rapeseed meal on performance, nutrient utilization, immunocompetence and carcass characteristics in lambs

Effects of dietary rapeseed meal on laying performance, egg quality, apparent metabolic energy, and nutrient digestibility in laying hens

The objective of the present study was to investigate the effects of low glucosinolates rapeseed meal (RSM) on laying performance, egg quality, nutrient digestibility, and AME in laying hens. A total of 900 thirty-week-old laying hens were randomly assigned to 6 dietary treatments with 10 replicates per treatment and 5 cages (3 hens) per replicate. The isoenergetic and isonitrogenous diets containing 0, 58.8, 117.6, 176.4, 235.2, and 294.0 g RSM/kg were formulated on a digestible amino acid basis. The study lasted for 12 wk. Results showed that the egg production and egg mass linearly decreased with the increased content of RSM (P < 0.01), and the feed conversion ratio (FCR) increased linearly during wk 1 to 12 (P = 0.003). The increasing RSM content had a quadratic effect on average egg weight (P < 0.01) and average daily feed intake (ADFI, P < 0.01) during wk 1 to 12. The increasing RSM content had a quadratic effect on apparent metabolic energy (AME), N, and amino acid digestibility at wk 12 (P < 0.04), except Tyr and Ser. Dry matter, Tyr, and Ser digestibility linearly decreased as the RSM concentration increased at wk 12 (P < 0.01). The egg albumen height decreased linearly at wk 4 and 12 (P < 0.01 and P = 0.02, respectively), and Haugh units decreased in a linear manner at wk 4 and 12 (P = 0.03 and 0.02). The egg yolk color increased linearly with increased content of RSM at wk 4 and 12 (P < 0.01). The serum triiodothyronine (T3) and thyroxine (T4) linearly increased as the RSM content increasing (P < 0.01). Using a one-slope broken-line analysis, the breakpoint (BP) for egg weight of daily RSM intake during wk 1 to 12 occurred at 13.6 g/hen. The daily RSM intake BP of egg production at wk 1 to 12 occurred at 6.5 g/hen. Supplementation of low glucosinolate RSM in hens’ diet should be lower than 117.6 g/kg in terms of egg production performance, egg quality, blood hormone content, nutrient digestibility, and AME.

Effect of different dietary levels of low-glucosinolate rapeseed (canola) meal and non-starch polysaccharide-degrading enzymes on growth performance and gut physiology of growing turkeys

Zdunczyk, Z., Jankowski, J., Juskiewicz, J., Mikulski, D. and Slominski, B. A. 2013. Effect of different dietary levels of low-glucosinolate rapeseed (canola) meal and non-starch polysaccharide-degrading enzymes on growth performance and gut physiology of growing turkeys. Can. J. Anim. Sci. 93: 353-362. One-day-old male turkey poults were randomly assigned to eight dietary treatments and were fed diets containing 0, 60, 120, or 180 g kg-1 of low-glucosinolate rapeseed meal (RSM) from 1 to 56 d of age without or with a commercial non-starch polysaccharide-degrading enzyme product containing pectinase, cellulase, xylanase, glucanase, mannanase and galactanase activities. There were no significant differences (P>0.05) in body weight and feed conversion ratio between the Control soybean meal-based diet and the diets containing RSM. Overall, the inclusion of up to 180 g kg-1 of RSM did not affect the growth performance of turkeys. When compared with the Control treatment, the diet with the lowest RSM content i...

Effect of different dietary levels of low-glucosinolate rapeseed (canola) meal and non-starch polysaccharide-degrading enzymes on growth performance and gut physiology of growing turkeys

Zduńczyk, Z., Jankowski, J., Juśkiewicz, J., Mikulski, D. and Slominski, B. A. 2013. Effect of different dietary levels of low-glucosinolate rapeseed (canola) meal and non-starch polysaccharide-degrading enzymes on growth performance and gut physiology of growing turkeys. Can. J. Anim. Sci. 93: 353–362. One-day-old male turkey poults were randomly assigned to eight dietary treatments and were fed diets containing 0, 60, 120, or 180 g kg−1of low-glucosinolate rapeseed meal (RSM) from 1 to 56 d of age without or with a commercial non-starch polysaccharide-degrading enzyme product containing pectinase, cellulase, xylanase, glucanase, mannanase and galactanase activities. There were no significant differences (P&gt;0.05) in body weight and feed conversion ratio between the Control soybean meal-based diet and the diets containing RSM. Overall, the inclusion of up to 180 g kg−1of RSM did not affect the growth performance of turkeys. When compared with the Control treatment, the diet with the lowest RSM content increased the pH of the small intestinal contents and the amounts of cecal digesta. The moderate level of RSM also increased the pH of the small intestinal contents although no increase in the cecal digesta contents was noted. In comparison with other treatments, the highest RSM content increased the content of the small intestinal digesta considerably and decreased the pH of the small intestinal contents to that of the Control treatment. All three dietary levels of RSM significantly reduced the activity of bacterial β-glucuronidase in the ceca. Enzyme supplementation tended to reduce ileal viscosity (P=0.079), decreased ammonia concentration, increased the glycolytic activities of the intestinal microflora enzymes α-glucosidase, α-galactosidase, and β-galactosidase, decreased the activity of β-glucuronidase and increased the growth rate of turkeys.

The effect of different dietary levels of rapeseed meal on growth performance, carcass traits, and meat quality in turkeys

The objective of this study was to determine the effect of different dietary levels of low-glucosinolate rapeseed meal (RSM) on growth performance, blood thyroid hormone concentration, carcass traits, and chemical composition, physicochemical properties, and fatty acid profile of breast meat in growing turkeys. The experiment lasted for 21 wk. Large White BIG-6 turkeys were fed isoenergetic and isonitrogenous diets containing 0, 60, 120, and 180 g/kg of RSM. Each experimental group was comprised of 7 replicates/pen of 28 birds each. There was no effect of graded levels of RSM on final BW. An increase in the inclusion rate of RSM was followed by a linear increase in feed conversion ratio, which was significantly higher (P < 0.05) in the group fed 180 g/kg of RSM. The blood levels of free triiodothyronine decreased significantly (P < 0.05) regardless of the dietary level of RSM. No significant changes in the carcass dressing percentage or the meat fat content were observed. Significant differences were found in the fatty acid composition and physicochemical properties of breast meat. The concentrations of margaroleic acid and saturated fatty acids, including myristic and palmitic acid, in meat from male turkeys fed 120 and 180 g/kg of RSM decreased linearly; whereas the levels of oleic acid and polyunsaturated fatty acids, including linoleic and linolenic acid (an n-3 fatty acid), increased linearly. An increase in RSM content of the diets was accompanied by the unfavorable changes in selected functional properties of meat, including a significant increase in drip loss in groups fed 120 g/kg of RSM (from 1.85 to 2.38%) and 180 g/kg of RSM (from 1.85 to 3.02%) and a decrease in Warner-Bratzler shear force values in turkeys fed 180 g/kg of RSM (from 19.1 to 15.8 N). The results suggest that the quality of turkey meat could be affected by impaired triiodothyronine secretion caused by dietary RSM.

Effect of replacing solvent-extracted canola meal with high-oil traditional canola, high-oleic acid canola, or high-erucic acid rapeseed meals on rumen fermentation, digestibility, milk production, and milk fatty acid composition in lactating dairy cows

The objective of this experiment was to investigate the effects of replacing conventional, solvent-extracted canola meal (control; CTRL) with high oil content; conventional, mechanically extracted canola meal (CMEC); high-oleic, low polyunsaturated fatty acid (FA) canola meal (HOLL); and high-erucic acid, low-glucosinolate rapeseed meal (RPS) on rumen function, digestibility, milk production, and milk FA composition in lactating dairy cows. The experimental design was a replicated 4×4 Latin square with 8 lactating dairy cows. Four of the cows were ruminally cannulated. All oilseed meals were included at approximately 12 to 13% of dietary dry matter (DM). Crude protein and fat concentrations (% of DM) of the meals were 43 and 3.1%, 32.8 and 16.1%, 45.2 and 13.7%, and 34.3 and 17.9% for CTRL, CMEC, HOLL, and RPS, respectively. All diets were formulated to supply net energy of lactation in excess of requirements. The CMEC and RPS diets were predicted to be about 1% deficient in metabolizable protein. Relative to the CTRL, inclusion of high-oil seed meals in the diet lowered ruminal acetate concentration and the molar acetate:propionate ratio and decreased DM intake. Milk yield generally followed DM intake and was lower for CMEC and RPS than the CTRL. Treatments had no effect on milk composition, other than an increase in milk urea nitrogen concentration for HOLL. Fat-corrected milk (3.5%) feed efficiency was increased by HOLL and RPS compared with CTRL. Urinary urea nitrogen losses were increased by HOLL, which, as a consequence, increased the ammonia-emitting potential of manure. The ratio of milk N-to-N intake was greater for CMEC and RPS. Replacing solvent-extracted canola meal with the high-oil meal decreased milk fat 12:0, 14:0, 16:0, and total saturated FA content and enhanced cis-9 18:1 and total monounsaturated FA concentrations. Relative to the CTRL, canola increased total trans FA in milk, whereas inclusion of HOLL in the diet increased trans-11 18:1 and cis-9, trans-11 CLA content. The RPS increased milk fat cis-13 22:1 content from 0.07 to 2.33g/100g of FA. In conclusion, HOLL or RPS, which are likely to come from small-scale biodiesel plants where oil is cold pressed without hexane extraction, fed at levels at or above 12 to 13% of dietary DM may decrease feed intake and milk production, but can be used to alter milk FA composition in lactating dairy cows.

The effect of low-glucosinolate rapeseed meal in diets with multi-enzyme supplement on performance and protein digestibility in broiler chicks

The effect of low-glucosinolate rapeseed meal in diets with multi-enzyme supplement on performance and protein digestibility in broiler chicks

Effect of long-term feeding with graded levels of low glucosinolate rapeseed meal on endocrine status of gilts and their piglets

Seventy-two crossbred gilts of approximately 30 kg initial weight were used in this study. The gilts were divided into three groups and fed with graded levels of low glucosinolate rapeseed meal (RSM) over grower–finisher, gestation and lactation periods as follows C (control: no RSM in diet during growth/pregnancy/lactation), M-RSM (medium RSM levels: 7/2.5/7% RSM in diet equivalent to 0.45/0.16/0.45 mM glucosinolates/kg diet) and H-RSM (high RSM levels: 12/5/12% RSM in diet equivalent to 0.78/0.32/0.78 mM glucosinolates/kg diet). In experiment 1, the jugular veins of six gilts taken randomly from each group were cannulated. Blood was sampled every 4 h over 2 days during the midluteal phase of the first oestrous cycle. Plasma concentrations of free thyroxine (FT 4), triiodothyronine (T 3), luteinizing hormone (LH), prolactin (PRL), progesterone (P 4) and androstenedione (A 4) were determined. After sacrificing, thyroid glands, ovaries and uteri were dissected and weighed, the lengths of the uterine horns were measured, and the numbers of corpora lutea (CL) were counted. Thyroid glands of gilts fed H-RSM diet were heavier ( P<0.01) than those of control gilts. Diets containing RSM did not affect ovarian and uterine weights, CL numbers or uterine horn lengths. The mean plasma concentration of FT 4 decreased as the content of RSM in the diet increased. Plasma T 3 was lower ( P<0.001) in gilts fed M-RSM diet and plasma P 4 was higher ( P<0.01) in gilts fed H-RSM diet compared to control animals. The concentrations of A 4 and PRL in gilts fed diets containing RSM were significantly lower than those in controls. There were no significant differences in mean levels of LH among groups. In experiment 2, the remaining 54 gilts were mated to study the reproductive performance and endocrine status of their offspring. Thirty female piglets were randomly chosen from different litters in each of the three groups on the 2nd and 35th day of lactation (five piglets/per group/per day). The piglets were sacrificed and blood was sampled from the heart. Thyroids, ovaries and uteri were dissected and weighed. Samples of blood serum were assayed for FT 4, T 3, LH and PRL. The weights of thyroids, ovaries and uteri in female piglets were similar in all groups. The serum concentrations of FT 4, T 3, LH and PRL were not affected by the treatment, irrespective of the age of piglets (2nd or 35th day). In summary, long-term feeding with graded levels of low glucosinolate rapeseed meal did not result in significant alterations in reproductive performance of gilts. The RSM diets, however, did affect the mean concentrations of plasma FT 4, T 3, PRL P 4 and A 4 in gilts during the midluteal phase of the first oestrus cycle. In contrast, no significant differences in serum concentrations of examined hormones were found in piglets originating from control and RSM groups.

Protection of Canola (Low Glucosinolate Rapeseed) Meal and Seed Protein from Ruminal Degradation - Review -

Protection of Canola (Low Glucosinolate Rapeseed) Meal and Seed Protein from Ruminal Degradation - Review -

Replacing soya bean meal with heat-treated, low-glucosinolate rapeseed meal does not affect the performance of growing-finishing pigs

A growth experiment was conducted to determine the suitability of heat-moisture-treated rapeseed meal (RSM) with a very low glucosinolate (GL) content (2.9 μmol g −1 defatted meal) as a substitute for soya bean meal (SBM) in pig feeding. The RSM was solvent extracted, toasted at 100°C (45 min.) and heat-moisture treated at 130°C (a few seconds, full-steam stage). In the four barley-based diets, 0, 33, 66 and 100% of SBM was replaced with RSM ( Brassica campestris cv. Kulta). The RSM diets were fortified with synthetic lysine to achieve a content of 7.5 g feed unit −1 (FU) of digestible lysine in the grower and 5.9 g FU −1 in the finisher diets (1 FU = 9.33 MJ NE). A total of 160 pigs (25–100 kg) was used in the trial and each diet was tested with ten pens of four animals (two gilts and two castrated male pigs). The pigs were fed according to Finnish feeding standards, with the daily FU intake restricted to 85–90% of the ad libitum level. The daily weight gain (WG) in the growing (786, 780, 793 and 784 g d −1) and finishing periods (847, 855, 842 and 844 g d −1) and the feed energy conversion ratio (19.3, 19.5, 19.3 and 19.8 NE MJ kg −1 WG in the growing and 28.9, 28.3, 29.0 and 29.4 NE MJ kg −1 WG in the finishing period) were unaffected by dietary RSM substitution. The slaughter loss percentage of the pigs increased linearly ( P < 0.05) when SBM was replaced by RSM, but otherwise carcass quality was similar. Inclusion of RSM in the diet did not affect the weight of the thyroid gland of the pigs (6.66, 8.06, 7.17 and 7.00 g). The organoleptic quality of the meat (taste, tenderness and juiciness) was similar in all treatment groups. The intramuscular fat content of the loin, however, declined ( P < 0.05) with increasing RSM substitution. Our results show that negative effects of GLs may be avoided when intake is below 1.2 mmol d −1. Thus heat-moisture-treated RSM with a very low GL content can, when fortified with lysine, be a satisfactory alternative to SBM in restricted feeding, even in the diets of growing (25–50 kg) pigs.

Effect of heat or formaldehyde treatment on the rumen degradability and intestinal tract apparent digestibility of protein in soya-bean meal and in rapeseed meals of different glucosinolate content

Three Hereford × Friesian/Holstein heifers were each fitted with rumen and simple T-piece duodenal cannulae. They were used in an experiment of latin square design to study the rumen degradability and intestinal apparent digestibility (using the mobile dacron bag technique) of protein in soya-bean meal (SBM) and in low and high glucosinolate rapeseed meals (LgsRSM and HgsRSM, respectively) each in untreated (UT), heat treated (HT) and formaldehyde treated (FT) forms. For rumen incubation times of 24 h there were no significant protein source × processing treatment interactions for either degrability of protein in the rumen (dgN) or for the proportion of food protein undegradable in the rumen and digestible in the small intestine (DUDN). At this time dgN values for FT, HT and UT were 0.263, 0.374 and 0.418 (SEM 0.0078; P < 0.001) respectively and DUDN values for SBM, LgsRSM and HgsRSM were 0.320, 0.348 and 0.386 (SEM 0.0078; P < 0.001) respectively. Compared with UT, and to a lesser extent HT, FT at all times after 0 h incubation significantly decreased dgN values and increased DUDN values for all three protein sources. Compared with UT, HT significantly decreased dgN. Apparent digestibility of the protein of SBM in the intestines was greater than that of LgsRSM and HgsRSM, and overall the values of available undegraded protein for FTLgs and HgsRSM, but not of FTSBM, were similar to or greater than for the UT sources. FT tended to decrease the total tract apparent digestibility of the protein sources.

Toxic moieties in ruminal and duodenal digesta and in milk, and hepatic integrity in cattle given diets based on rapeseed meals of different glucosinolate contents either untreated or treated with heat or formaldehyde

In each of two experiments cattle were given diets based on (300 g kg −1) either high (60.7 mmol g −1) or low (29.0 mmol g −1) glucosinolate rapeseed meals (HgsRSM and LgsRSM, respectively), each untreated (UT), heat-treated (HT) or with formaldehyde added (FT), with untreated soyabean meal (UTSBM) used as a control in the second experiment. Concentrations of toxic moieties, released from hydrolysis of the glucosinolates present, in ruminal and in duodenal digesta (using heifers fitted with both rumen and duodenal cannulae), and in milk and in urine, and their effect on the liver as evidenced by concentrations of glutamate dehydrogenase (GLDH) in serum and glutathione (GSH) in blood, were determined. There were no significant protein source-processing treatment interactions or significant differences between the UT, HT and FT treatments for any of the variables studied ( P> 0.05), and only in urinary concentrations and total daily excretion in the urine of thiocyanate (SCN) were there significant differences between the diets containing the LgsRSM and HgsRSM (LgsRSM > HgsRSM; P < 0.01). In ruminal and duodenal digesta there were no detectable quantities of isothiocyanate (ITC), 5-vinyl oxazolididine-2-thione (OZT) or of the nitrile 1-cyano-2-hydroxy-3-butene (NCHB) from any of the diets, but SCN was found in ruminal, but not in duodenal, digesta from the LgsRSM and HgsRSM diets. Compared with giving diets containing the SBM, diets containing LgsRSM and HgsRSM gave significantly higher concentrations of GLDH in serum and significantly lower concentrations of GSH in blood. No detectable quantities of ITC or OZT were found in milk, and only traces of NCHB, but SCN was found from both the LgsRSM and HgsRSM diets, and concentrations and total daily secretions were significantly higher than from the SBM diet.

Food ingredient selection by growing and finishing pigs: effects on performance and carcass quality

AbstractThe aim was to investigate if selection of a balanced diet by growing and finishing pigs from foods differing in protein content is modified by the intrinsic nutrient and chemical properties of the high protein food ingredient offered. The treatments were as follows: a free-choice was offered between milled barley and either soya-bean meal (SBM) or low-glucosinolate rapeseed meal (RSM) or an equal mixture of SBM and RSM (SBM+RSM). In two further treatments (SBM/RSM and RSM/SBM) the protein supplements were changed when pigs reached 50 kg. These were compared with a control diet (CONT) formulated to provide 13-0 MJ digestible energy (DE) and 10 g lysine per kg and containing barley (680 g/kg), SBM (150 g/kg) and RSM (150 g/kg). A total of 72 pigs weighing about 30 kg were randomly allocated to the treatments in groups of six (three boars and three gilts). Pigs were slaughtered at about 90 kg and the chilled carcasses were assessed by measuring subcutaneous fat depths and cross-sections of the eye-muscle at the last rib. Responses from 30 to 90 kg on treatments CONT, SBM, RSM and SBM+RSM were, for food intake 2·57, 2·37, 2·21 and 247 (s.e. 0·08) kg/day (P &lt; 0·05), for growth rate 0·93, 0·87, 0·70 and 0·82 (s.e. 0·05) kg/day (P &lt; 0·05) and for food conversion 2·77, 2·72, 3·17 and 3·01 (s.e. 0·181) kg food per kg growth (P &gt; 0·05) respectively. The amount of protein supplement selected in the diet from 30 to 90 kg on treatments SBM, RSM and SBM+RSM averaged 524, 495 and 483 (s.e.d. 64·9) g/kg respectively. With SBM this proportion decreased with increasing body weight (P &lt; 0·01; R2 = 0·58). Changing RSM to SBM at 50 kg increased preference for the protein supplement and intake of SBM averaged 983 g/kg from 50 to 90 kg. On the other hand, switching from SBM to RSM increased preference for barley and intake of RSM averaged 572 g/kg. There were no significant differences in carcass quality but treatments RSM and SBM/RSM tended to produce increased fat depths. In conclusion, the use of RSM did not give a satisfactory level of -performance under the restricted free-choice feeding environment of this study. Preference and nutrient intake were adversely modified by RSM possibly due to the undesirable effects of antinutritive factors.

Rapeseed meal‐Glucosinolates and their antinutritional effects Part 6. Taint in end‐products

From the present review it is clear that glucosinolates and their breakdown products may pass in small amounts into such products as meat, milk or eggs without noticeable deterioration in their taste. When applying low glucosinolate rapeseed meal (LG-RSM) as the sole high protein component of concentrate mixture for cows, the level of rapeseed glucosinolates breakdown products should not exceed 0.1 mumol/l oxazolidinethione, 10 mumol/l unsaturated nitriles and 100 mumol/l thiocyanate. At these levels no evidence has been found to indicate the negative influence of glucosinolates breakdown products on the sensory properties of milk or threat for consumers. No published information appears to be available suggesting that glucosinolates have any deleterious effect on the carcass flavour in cattle. Even at a 20% inclusion of LG-RSM in diets no impairment on visual scores or sensory evaluation was found in pig's or broiler's carcass. Glucosinolated, chiefly progoitrin, which depress trimethylamine oxidation thus clearly affect the taint in eggs. In birds with genetically conditioned susceptibility (brown layers) fishy taint can be observed even at 0.3 microM progoitrin, i.e. approximately 0.5 microM total glucosinolates in 1 g diet. Assuming a threefold higher threshold for white layers (1 microM progoitrin in 1 g diet) fishy taint can be expected at a 10% LG-RSM level in diet, and only very low glucosinolate rapeseed meals can be fed to layers without the risk of fishy taint in eggs.

Effect of heat or formaldehyde treatment and differences in basal diet on the rumen degradability of protein in soyabean meal and in rapeseed meals of different glucosinolate content

Using four heifers fitted with permanent rumen cannulae in six experiments, studies were made of the effects on in sacco degradability (over 24 h), fractional outflow rate from the rumen and, from these two measures, effective degradability, of the protein in soyabean meal (SBM) and high (HgsRSM) and low (LgsRSM) glucosinolate rapeseed meals (91.7 and 28.8 μmol g −1 total glucosinolates respectively) either untreated, heated at 110°C for 2 h or with 0.8 g 100 g −1 of 30% (w/v) formaldehyde solution added. All supplements were examined using a basal diet either of hay only or one of composition (g kg −1) hay 550, concentrate 450. Overall the results indicated for the untreated protein sources and for the two basal diets, faster fractional outflow rates and higher in sacco degradability and effective degradability for SBM compared with HgsRSM and LgsRSM and for the hay only compared with the hay and concentrate mixed basal diets. Both heat treatment and formaldehyde additions reduced degradability, more so of the SBM than of the RSMs, and for formaldehyde treatment than for heat treatment, and the LgsRSM tended to be less degradable than the HgsRSM. Effective degradability values tended to be greater than in sacco values at 24 h incubation.

Improvement in the nutritive value of high and low glucosinolate rapeseed meal by aqueous extraction

In spite of the reduction of glucosinolate content, the use of rapeseed meal is still limited in animal diets to avoid metabolic disorders. In order to evaluate the responsibility of glucosinolates (GSL) in these deleterious effects, nutritional trials were carried out on chickens fed with diets based on rapeseed meal. Two rapeseed meal fractions obtained by cold aqueous extraction from a dehulled rapeseed meal ( Brassica napus L.) were used. The GSL content was 168.9 μmol g −1 dry matter in the extract and 2.88 μmol g −1 dry matter in the residue. These two fractions, alone or associated, as well as the initial rapeseed meal were incorporated in the diets used to feed the chickens during the first 4 weeks of life. The diet containing the extract reduced significantly the chicken weight (− 14%) and induced hypertrophies of liver (+ 17%), thyroid (+ 154%) and kidney (+ 8.5%). Similar effects on these organs were observed with the other diets, except the control one with no rapeseed added and the one prepared with the residue of extraction free from glucosinolates. The latter results indicate that cold water extraction can remove toxic factors in rapeseed meal while keeping good nutritional value. Mean contents of 5-vinyl-1,3-oxazolidine-2-thione (5-VOT) found in liver, thyroid, kidney, muscle and plasma varied in connection with progoitrin amount in the feeds. However, great variations with individual chickens were noticed and no significant correlation was observed between 5-VOT contents and the weights of animals or target organs. In spite of an identical glucosinolate content, the diet prepared with the extract alone or associated with the residue of extraction was found more toxic than the diet prepared with the initial rapessed meal. Glucosinolate content in rapeseed fractions did not appear as the only parameter responsible for the toxicity, which was, in the present experiment increased by cold aqueous extraction. The glucosinolate rich extract will require further fractionation in order to isolate the factor(s) of toxicity.

Effects of enzyme supplementation on the digestion of low glucosinolate rapeseed meal in vitro, and its utilization by broiler chicks

Effects of enzyme supplementation on the digestion of low glucosinolate rapeseed meal in vitro, and its utilization by broiler chicks

Rapeseed meal‐glucosinolates and their antinutritional effects Part 5. Animal reproduction

Although there is no clear evidence to fully describe the mechanism involved in glucosinolate-related effects on animal reproduction, lowered fertility in animals fed diets with rapeseed meal (RSM) inclusion is related to glucosinolate content in the diet. Negative effects can result both from multidirectional action of glucosinolates, malnutrition of mother due to the thyroid dysfunction, transfer of goitrogenic compounds to foetus and reduced transfer of nutritive compounds (e.g. iodine) through the placenta. The degree of reproduction impairment depends both on glucosinolate content and on the type of animal. Pregnant female rats are sensitive to the presence of glucosinolates, and the first symptoms of fertility impairment and lowering of offspring survival rate may occur at low glucosinolate levels, e.g. with diets containing low glucosinolate rapeseed meal (LG-RSM). In the case of swine, the limiting value above which sows fertility may be impaired is 4 mumol of total glucosinolates per g diet and 8 mmol of daily intake of these compounds. Opinions on the permitted RSM inclusion in diet for hens are very divergent. Some authors recommend limiting of the RSM inclusion to 10%, while others did not find any lowering of egg production in hens fed with two- or three-fold greater RSM inclusion rates. Most long-term experiments with heifers, cows and ewes indicate that ruminants tolerate the level of glucosinolate in LG-RSM although feeding this fodder as the only high-protein concentrate component may lead to impaired fertility.

Rapeseed meal‐glucosinolates and their antinutritional effects. Part II. Flavour and palatability

AbstractThis paper has reviewed the current literature relating to the effects of glucosinolates on the palatability of rapeseed meal. The available evidence indicates that diet palatability can be adversely affected by rapeseed meal inclusion and that this response is related to glucosinolate level. However the response is variable and depends also on the species of animal, age and growth state. Younger animals, particularly chicks, piglets and calves appear to be more severely affected and exhibit reduced intake and hence depressed performance with diets containing high levels of glucosinolates from high glucosinolate rapeseed meal. Palatability is substantially improved by the use of low glucosinolate rapeseed meal (LG‐RSM) containing 10–30 μ/g and very low glucosinolate rapeseed meal (VLG‐RSM) containing 1–5 μ/g glucosinolates. From the findings of this review, it can be concluded that LG‐RSM and VLG‐RSM can be included at levels up to 20% and 30% for calves and dairy cows respectively. Since piglets are particularly sensitive it is suggested that rapeseed is excluded from early starter diets but that low glucosinolate meals can be included at levels of 10% and 15% for grower and finisher pigs respectively. Growing poultry may be less sensitive to palatability problems associated with rapeseed meal but the use of high levels is constrained due to the lower energy and higher fibre contents of RSM compared with soybean meal.