Extrusion decreases the negative effects of kidney bean on enzyme and transport activities of the rat small intestine

The objective of the present study was to evaluate the influence of raw and extruded kidney bean (Phaseolus vulgaris L. var. Pinto) consumption on the gut physiology of young growing rats. The intestinal enzyme activity (sucrase, maltase, Na(+) /K(+) ATPase, aminopeptidase N, dipeptidylpeptidase IV, alkaline phosphatase) and the uptake of sugar (d-galactose) and amino acids (l-leucine) were measured in brush border membrane vesicles. Five groups of growing male Wistar rats were fed ad libitum for 15 days on five different 10% protein diets: one containing casein as the main source of protein (Control, C), and four containing raw (RKB1, RKB6) or extruded kidney bean (EKB1, EKB6) at 1% and 6% of total protein content respectively. Extrusion treatment significantly reduced the content of bioactive factors (phytates, tannins) and abolished lectins, trypsin, chymotrypsin, and α-amylase inhibitory activities. Rats fed raw beans (especially RKB6) showed lower growth rate and food intake as compared to those fed extruded legumes, probably due to the high levels of lectins and other anti-nutritive factors in the raw beans. Gut enzymatic activities and uptake of d-galactose and l-leucine were lower in RKB6 and RKB1-fed animals, although they significantly improved in the groups fed extruded beans. Enzymatic activity and uptake in EKB1 were similar to those of casein-fed rats, whereas the uptake and growth rate of EKB6 were different to the control. This is attributable to the higher non-thermolabile biofactor content in the EKB6 diet, especially phytates and tannins, than in EKB1. This article shows the dose-dependent toxicological effects of bioactive factors contained in kidney beans on gut function. The extrusion process reduced their adverse impact on gut physiology and growth rate.     

Diets containing leguminous seeds influence chromium content in the rat femur bone

Leguminous seeds contain a lot of antinutritional factors (ANFs) such as protease inhibitors, lectins and condensed tannins which can affect bioavailability of nutrients. Detrimental effect of protease inhibitors can be decreased by sulphur amino acids addition. Moreover, most of the leguminous ANFs are thermolabile. Hence, legumes tested in our study were extruded and/or diets were supplemented with methionine and cystine (0.15% + 0.15%). The present experiment was performed for 28 days on 90 Wistar rats divided into nine feeding groups. Semipurified diets (10% casein) were supplemented (10%), except the control one, with soybean (S) or faba bean (F), raw (R) or extruded (E), with addition of sulphur amino acids (SAA) or without them. The Cr concentration was determined in the femur bone. Total feed intake during whole trial widely varied among the groups and was the lowest in SR (289 g) and FR (294 g) groups. There was no correlation between feed intake and Cr content in the femur bone. Generally, 10% soybean in the diet decreased Cr concentration in the bones, and faba bean increased it. The SAA addition to diets generally increased femur Cr content. However, there was a significant interaction between SAA supplementation and extrusion of faba bean, hence, the effect of their combination was unclear.     

The possible role of methionine in the detoxification of faba bean (Vicia faba L.) tannins in chick diets

1. A metabolism trial was designed to investigate the role of methionine as a specific detoxifying agent of the condensed tannins present in faba beans (Vicia faba L.).

2. A 5 x 5 factorial approach was employed where 5 concentrations of dietary methionine were obtained (ranging from 3.9 to 12.15 g/kg diet dry matter) by the addition of DL‐methionine, and 5 concentrations of condensed tannins (ranging from 0.5 to 19.7 g/kg diet dry matter) by altering the ratio of tannin‐free and tannin‐containing faba bean hulls added to a basal diet.

3. The intake of condensed tannins had a significant, depressive effect on apparent available nitrogen (P< 0.001) and nitrogen corrected apparent metabolisable energy (AME_n ) (P< 0.001). There was no interaction between methionine and tannin (P>0.05). Thus the depressive effect of tannin was independent of methionine levels in the diet.

4. Methionine does not act as a specific detoxifier of faba bean condensed tannins.     

Ruminal fermentation and degradation patterns, protozoa population and urinary purine derivatives excretion in goats and wethers fed diets based on olive leaves

Olives leaves, accrued during the processing of olive harvests for oil extraction, are poor in N, rich in crude fat and ADF (1.19, 8.03 and 28.2 g/100 g of DM, respectively), and relatively low in condensed tannins (11.1 mg/g of DM). Three experiments were conducted in a 2 x 3 (two animal species: goats vs. wethers; and three experimental diets: olive leaves without or with polyethylene glycol supply and olive leaves supplemented with barley and faba beans) factorial design to evaluate ruminal degradation and passage kinetics (Exp. 1), fermentation pattern and protozoa population (Exp. 2), and urinary purine derivatives excretion (Exp. 3). Polyethylene glycol was supplied to evaluate the effects of condensed tannins contained in olive leaves. Ruminal degradability of CP was low in both goats and wethers, although goats showed higher (P < 0.05) values than wethers. Supplementation of olive leaves with barley and faba beans increased (P < 0.001) ruminal degradability of DM and CP. Both goats and wethers fed olive leaves showed similarly low particulate fractional passage rates (0.021 and 0.023/h, respectively). Ingestion of olive leaves promoted low NH3-N and VFA concentrations, which reflect poor microbial activity. These concentrations, especially that of VFA, increased when barley and faba beans were added. Ingestion of olive leaves affected ruminal protozoa: Entodiniomorphida showed low concentrations and Holotricha completely disappeared. When animals received a diet based on olive leaves, barley, and faba beans, Holotricha appeared in the ruminal liquor and Entodiniomorphida increased (P < 0.001). In goats and wethers fed olive leaves alone, urinary allantoin excretion was very low (163 and 164 micromol/kg BW0.75 in goats and wethers, respectively), and moderate values (352 and 389 micromol/kg BW0.75 in goats and wethers, respectively) were observed when a diet of olive leaves, barley, and faba beans was fed. The polyethylene glycol supply did not have an effect in goats or in wethers, indicating the lack of an effect of condensed tannins in olive leaves. Ingestion of olive leaves promotes a low microbial activity, although its supplementation with readily degraded carbohydrates and protein improves microbial activity and, as a consequence, increases its ruminal degradation. In general, for most of the measured variables, there were no animal species x diet interactions. Thus, goats and wethers had similar ruminal activities when fed diets based on olive leaves.     

Methodological impact of starch determination on starch content and ileal digestibility of starch in grain legumes for growing pigs

Background: Grain legumes represent a valuable energy source in pig diets due to their high starch content. The present study was conducted to determine the content and apparent ileal digestibility(AID) of starch in different grain legume cultivars for pigs by means of both a polarimetric and enzymatic method for starch determination.Methods: Three experiments were conducted with six barrows each which were fitted with ileal T-cannulas. In total, 18 diets including six different cultivars of faba beans(Vicia faba L.) and peas(Pisum sativum L.), five different cultivars of lupins(Lupinus luteus L., Lupinus angustifolius L.), and one diet with a soybean meal(SBM) were fed.Results: The starch content of faba beans and peas was greater(P 0.05) when determined polarimetrically than enzymatically(438 vs. 345 g/kg dry matter(DM) in faba beans and 509 vs. 390 g/kg DM in peas, respectively).Considerable lower starch contents were obtained in lupins and SBM, with 82 and 48 g/kg DM(analyzed polarimetrically) and 1.1 and 3 g/kg DM(analyzed enzymatically), respectively. Mean values for contents of neutral detergent fiber(NDF) and acid detergent fiber(ADF) in grain legumes ranged from 111 and 79 g/kg DM in peas to248 and 207 g/kg DM in lupins, respectively. Contents of condensed tannins in the colored flowered faba bean cultivars ranged from 2.1 to 7.4 g/kg DM. The AID of starch was greater(P 0.05) in pea than in faba bean cultivars,and using the polarimetric starch determination method resulted in greater(P 0.05) digestibility values than using enzymatic starch analysis(84 vs. 80% in faba beans and 86 vs. 83% in peas). Moreover, AID of starch differed(P 0.05)within pea cultivars and starch digestibility in faba beans decreased linearly(P 0.05) as the content of condensed tannins increased. However, there was no relationship between contents of NDF and ADF and AID of starch in pea and faba bean cultivars.Conclusion: Both contents and AID of starch in grain legumes can vary as influenced by the analytical method used for starch determination. Generally, starch digestibility is greater when measured by polarimetric rather than enzymatic methods.     

Influence of growing season,tannin content and autoclave treatment on the nutritive value of near-isogenic lines of faba beans (Vicia faba L.) when fed to leghorn chicks

1. The objective of this study was to determine the influence of heat-treatment (autoclaving) on the utilisation by chicks of near-isogenic lines of faba beans that were either tannin-free (Winter-white or Spring-white) or had tannins in the seed coat (Winter-coloured or Spring-coloured). The effect of heat treatment on a common tannin-containing cultivar, Diana, was also studied. 2. The nitrogen-corrected apparent metabolisable energy (AMEn) values of diets containing 600 g faba beans/kg diet were affected by tannin content and autoclave treatment of faba beans, with 59% of total variance in AMEn being attributable to the effect of autoclaving. The AMEn values were 9% higher for chicks fed on the autoclaved compared with those fed on diets containing the raw faba beans, 5% higher for the near-isogenic faba beans with no tannins compared with those with tannins, and 4% higher for the Winter compared with the Spring cultivars. 3. The above study was carried out on droppings obtained by total collection. Similar but not identical trends were obtained when AME was calculated using the chromic oxide index method ( r = 0.91). 4. Both autoclaving and the use of tannin-free faba beans improved the apparent protein digestibility (APD) of the diets by similar amounts (4% as determined by the total collection method and 6% as determined by the chromic oxide index method). 5. The digestibility of most amino acids either alone or together was affected by a culti- var X tannin X processing interaction. The cultivar by tannin interaction demonstrated that autoclaving increased the digestibility of amino acids to a greater degree when the tannin-containing (for example, 9% for lysine) than when the tannin-free faba beans (4% for lysine) were used in the diets. 6. The improvements in AMEn , APD and total amino acid digestibilities of faba beans following heat treatments ranged from 18% to 33%, 5% to 16% and 5% to 11%, respectively. The results demonstrate that the method of analysis can affect the values obtained but that they do not change the overall pattern of results. The results also suggest that, in most cases, more than half of the response to heat treatment is associated with the inactivation of tannins while the balance of the response is attributable to an effect of heat treatment on the non-tannin-containing factors. In summary, heat treatment can improve the utilisation of faba bean by chickens especially when they contain tannins. 7. Chicks, unlike rats, do not seem to adapt to tannins as the excretion of 3 amino acids that are the main constituents of a proline-rich protein were not affected by dietary tannins.     

Effects of toasting,inclusion levels and different enzyme supplementations of faba beans on growth performance of broiler chickens

Faba beans (Vicia faba) are an alternative protein source that likely can be used to a higher extent in broiler diets. White-flowered faba beans contain antinutritional substances (ANS) such as non-starch polysaccharides (NSP), trypsin inhibitors, and lectins, which might limit its inclusion level. Lectins and trypsin inhibitors are heat labile and previous studies have shown that steam-pelleting and enzyme treatment improves the nutritional value of faba beans. However, alternative to pelleting would facilitate for farmers to add faba beans on-farm. Currently, there are machines available for toasting faba beans on-farm, which might be used for broiler mash diets. The objective of this study was to investigate the effect of inclusion level (0, 10, 20 and 30%), toasting (140°C 5.5 min) and different enzymes (xylanase + phytase vs. xylanase, phytase, amylase, protease) of faba bean diets on growth performance and organ parameters in broilers. To test this, 2 experiments 34 and 35 days, using a total of 480 chickens were performed. Feed intake, body weight (BW) and feed conversion ratio were registered weekly, in addition, organ and carcass weights were registered at slaughter. The results showed that inclusion of 20% faba beans is possible in a pelleted diet with maintained broiler growth performance. When 20% was included in a mash diet, feed intake and BW decreased compared to chickens fed pelleted diets, irrespectively of pre-toasting of the beans. It can be concluded that toasting cannot replace pelleting. Supplementation of protease and amylase in addition to xylanase and phytase did not improve the nutritional value of faba beans.     

Pancreatic exocrine secretion and plasma concentration of some gastrointestinal hormones in response to abomasal infusion of starch hydrolyzate and/or casein

Eight Angus steers (290 +/- 8 kg), surgically prepared with pancreatic pouch-duodenal reentrant cannulas and abomasal infusion catheters were used in a replicated 4 x 4 Latin square experiment to investigate the effects of abomasal infusion of starch hydrolyzate (SH) and/or casein on pancreatic exocrine secretion and plasma concentration of hormones. Steers were fed a basal diet of alfalfa (1.2 x NEm) in 12 equal portions daily. Abomasal infusion treatments (6-L total volume infused per day) were water (control), SH [2.7 g/(kg BW x d)], casein [0.6 g/(kg BW x d)], and SH + casein. Periods were 3 d for adaptation and 8 d of full infusion. Pancreatic juice and jugular blood samples were collected over 30-min intervals for 6 h on d 11. Weight and pH of pancreatic samples were measured, and a 10% subsample was composited and frozen until analysis of total protein and pancreatic enzyme activities. The remaining sample was returned to the duodenum. Plasma was harvested and frozen until analyzed. Pancreatic juice (67 mL/h) and protein (1.8 g/h) secretion rates were not affected by nutrient infusion. There were SH x casein interactions for all pancreatic enzyme secretions (U/h; alpha-amylase, P < 0.03; trypsin, P < 0.08; and chymotrypsin, P < 0.03) and plasma insulin concentration (P < 0.10). Secretion of pancreatic enzymes was increased by SH (trypsin) and casein (alpha-amylase, trypsin, and chymotrypsin) but not when SH + casein were infused together. Glucose (P < 0.10) and cholecystokinin octapeptide concentrations (CCK-8; P < 0.05) were increased by SH, but glucagon was decreased (P < 0.10). Casein decreased (P < 0.10) plasma CCK-8 concentrations. These data indicate that positive effects of postruminal casein on enzyme secretion were inhibited by SH, emphasizing the complexity of the regulatory mechanisms involved in dietary adaptation of pancreatic exocrine secretion. Changes in hormone concentration may not relate directly to changes in enzyme secretion.     

Pancreatic mass, cellularity, and alpha-amylase and trypsin activity in feedlot steers fed diets differing in crude protein concentration

Twenty-four yearling beef steers (initial BW = 510 +/- 4.9 kg) predominantly of Angus breeding were used in a randomized complete block design to determine the effect of dietary CP concentration on pancreatic cellularity, mass, and alpha-amylase and trypsin activities. Treatment diets were formulated to contain 8.8, 11.0, 13.2, and 15.4% CP. Soybean meal and Top Soy (ruminal bypass soybean meal) were used as supplemental protein sources to ensure that MP intake was increased with increasing dietary CP concentrations. Steers were penned in groups of 4 (1 steer per treatment) and individually fed at 2.5x the NE(m) requirement by using Calan gates for 28 d before tissue collection. Four steers (1 pen) were slaughtered per week. Pancreases were weighed, subsampled, frozen in liquid N(2), and stored at -80 degrees C until analyses for DNA, RNA, and protein concentrations, and alpha-amylase and trypsin activities. Pancreatic weight (g and g/kg of BW) did not differ among treatment groups. Pancreatic DNA concentration (mg/g) decreased linearly (P = 0.06) with increasing CP concentration. Pancreatic protein (g/pancreas) increased linearly (P = 0.08) with increasing dietary CP concentration. Pancreatic alpha-amylase activity (U/g, U/mg of DNA, U/g of protein, U/pancreas, and U/kg of BW) increased linearly (P < or = 0.04) with increasing dietary CP concentration. Pancreatic trypsin activity (U/g, U/g of DNA, U/g of protein, U/pancreas, and U/kg of BW) increased linearly (P < or = 0.09) with increasing dietary CP concentration. Pancreatic alpha-amylase and trypsin activities (U/mg of RNA) responded quadratically (P < or = 0.09), with the greatest alpha-amylase activity observed in the 13.2% CP treatment. These data indicate that increasing dietary CP concentration decreases pancreatic cell numbers and also increases the concentration and content of pancreatic alpha-amylase and trypsin activities. Changes in cell number and size may be important factors regulating digestive enzyme production in the pancreas of cattle.     

Studies on the incorporation of velvet bean (<Emphasis Type="Italic">Mucuna pruriens</Emphasis> var. <Emphasis Type="Italic">utilis</Emphasis>) as an alternative protein source in poultry feed and its effect on growth performance of broiler chickens

The effect of replacement of soybean meal by the velvet bean meal as an alternative protein ingredient on the growth performance of broiler chickens was investigated. The raw seeds of velvet bean [Mucuna pruriens (L.) DC. var. utilis (Wall. ex Wight) Baker ex Burck], an under-utilized food legume collected from South India, was found to contain appreciable levels of crude protein (273.2 g/kg DM), lipid (60.61 g/kg DM), neutral detergent fiber (84.3 g/kg DM), and ash content (56.04 g/kg DM). Soaking in 0.2% sodium bicarbonate solution + autoclaving treatment caused a substantial reduction on the levels of various antinutritional compounds such as tannins (84%), l-Dopa (79%), phytic acid (87%), raffinose (93%), stachyose (83%), verbascose (73%), haemagglutinating activity (84%), trypsin inhibitor activity (77%), and α-amylase inhibitor activity (78%) without affecting the nutritional quality of velvet bean seeds. The processed velvet bean meal was incorporated as an alternative protein source by replacing soybean meal protein at 0, 20%, 40%, 60%, 80%, and 100% levels in the broiler diets. Replacement of soybean meal protein up to 40% level, which corresponds to the inclusion of velvet bean meal up to 15.7% and 11% in the starter and finisher phase poultry feeds, respectively, exhibited better growth performance of broiler birds without any adverse effects.     

Relation of soya bean meal level to the concentration of plasma free amino acids and body growth in white rats

Amino acid (AA) levels in plasma and body growth were determined in rats (n20) fed diets with different soya bean meal levels. Free AA in plasma was determined by reversed-phase high-pressure liquid chromatography. We have used four levels of protein diets like 8%, 15%, 23% and 35% in this trial. Rats which were fed the low-protein (8%) diet with low percentage of soya bean meal were found to be growth-retarded. The body weight gain of high protein group (35%) was lower than that of the 23% groups. In the rats fed with the low-soya bean meal diet, some nonessential AA (NEAA) in plasma like asparagine, aspartic acid, cysteine, glutamic acid and serine increased, whereas the essential AA (EAA), with the exception of arginine, methionine and valine decreased. Here, plasma EAA-to-NEAA ratios were not correlated to growth and experimental diet. We hypothesize that AA metabolism is associated to changes in growth in rats on different protein intake. This study has showed the sensitivity of body mass gain, feed intake, feed conversion rate of rats to four levels of protein in the diet under controlled experimental conditions.     

Response of broiler chickens to microbial phytase supplementation as influenced by dietary phytic acid and non-phytate phosphorus contents. I. Effects on bird performance and toe ash

1. Seven-day old male broilers (n=900) were fed on wheat-sorghum-soyabean meal-based diets containing 3 concentrations of phytic acid (10.4, 13.2 and 15.7 g/kg; equivalent to 2.9, 3.7 and 4.4 g/kg phytate phosphorus), 2 of non-phytate phosphorus (2.3 and 4.5 g/kg) and 3 of microbial phytase (Natuphos 5000 L; 0, 400 and 800 FTU/kg) in a 19-d trial. The dietary phytic acid contents were manipulated by the inclusion of rice pollard. 2. Each dietary treatment was fed to 5 pens (10 birds/pen) from 7 to 25 d of age. Records of body weight, food intake and mortality were maintained. On d 25, all surviving birds were killed and toe samples were obtained for toe ash measurements. 3. Increasing dietary phytic acid negatively influenced body weight gain, food intake and food/gain. These adverse effects were partially overcome by the addition of microbial phytase. 4. Supplemental phytase caused improvements in weight gain and food efficiency of broilers but the magnitude of the responses was greater in low non-phytate phosphorus diets, resulting in significant non-phytate phosphorus x phytase interactions. 5. Toe ash contents were improved by phytase addition but the response was greater at the highest concentration of phytic acid, resulting in a significant phytic acid x phytase interaction. Responses were also greater in low non-phytate phosphorus diets as indicated by significant non-phytate phosphorus x phytase interaction. 6. In general, there was very little difference in the responses to phytase additions at 400 and 800 FTU/kg. 7. The performance responses to added phytase in birds receiving adequate non-phytate phosphorus diets provide evidence for the influence of the enzyme on animal performance independent of its effect on phosphorus availability.     

Digestibility for dogs and cats of meat and bone meal processed at two different temperature and pressure levels*

This study evaluated the effect of two rendering processes applied to meat and bone meal (MBM) production, associated or not with extrusion, by measuring diet apparent total tract digestibility of dogs and cats, and true digestibility of amino acids (AA) by cecectomized roosters. Four diets were evaluated, with the main protein source as follows: conventional and extruded MBM; high temperature and pressure (HPT; 135 °C, 3 bar, 20 min) and extruded MBM; conventional non‐extruded MBM; HPT non‐extruded MBM. Nutrient digestibility and food metabolizable energy content were evaluated with dogs and cats by the method of total collection of faeces. True AA digestibility was evaluated by a precision‐fed assay with cecectomized roosters. The evaluated MBM had high‐ash content. The HPT process of MBM increased the digestibility of crude protein of the diets by cats, and the true digestibility of several AA by cecectomized roosters. The extrusion process did not modify the apparent total tract nutrient digestibility of MBM by dogs and their amino acid digestibility by roosters, but increased the digestibility of the dietary protein by cats. Dogs fed HPT MBM presented a higher urea post‐prandial response, suggesting reductions in bioavailability and protein synthesis from absorbed AA.     

Optimum inclusion of field peas, faba beans, chick peas and sweet lupins in poultry diets. I. Chemical composition and layer experiments

1.Experiments were undertaken to determine the chemical composition and apparent metabolisable energy (AME) of field peas, faba beans, sweet lupins and chick peas and the production of hens when each was included in nutritionally similar diets at 250 g/kg in 2 experiments. 2. Amino acid composition, crude protein and AME agreed well with previously published measurements. Detailed analysis of the non-starch polysaccharides (NSPs) showed that sweet lupins were much higher than the other grain legumes in the soluble NSPs and that the NSPs were particularly high in arabinose. The condensed tannin content was highest in field peas followed by faba beans. 3. In the 1st layer experiment over 40 weeks, hen-day egg production was lowest on the faba bean-based diet and egg weight and egg mass were also lowest. Relative viscosity of digesta in the small intestine of hens fed on the sweet lupin-based diet was highest, followed by that of hens fed on field peas. Enlargement of the pancreas was observed in hens consuming chick peas. 4. In experiment 2, in which only sweet lupins and faba beans were used, steam or cold pelleting showed few effects, nor did dehulling of faba beans but egg weight was lower when diets were steam pelleted. Daily food intake was 5.7 g/bird lower on the steam than cold pelleted diets and food conversion ratio tended to be improved (P=0.082). 5. It was concluded that field peas could support good production at 250 g/kg of layer diet. Although chick peas and sweet lupins supported good performance, there was concern about the increased weight of the pancreas and high gut viscosity respectively. Faba beans showed similar hen-d egg production in the 2nd experiment to that of sweet lupins but egg weight tended to be about 0.8 g lower than when on the sweet lupin-based diets.     

Digestion of soybean meal and canola meal protein and amino acids in the digestive tract of young ruminants

Eight male Holstein calves (body weight 68 +/- 5 kg; age 75 +/- 6 d), each with a permanent re-entrant pancreatic cannula and T-type ileal and duodenal cannulas, were used in a crossover design with four animals per group to determine amino acid kinetics and digestibilities in the digestive tract of calves fed soybean meal (SBM) and canola meal (CM) protein. The SBM and CM diets were fed twice daily at a level of 900 g at each feeding time (air-dry basis). With the exception of methionine, crude protein and amino acid flows at the proximal duodenum, expressed as a percentage of intake, were not influenced by dietary protein source. Apparent ileal and total tract digestibilities of CP and amino acids were reduced (P less than .05) by feeding CM compared to SBM, but apparent ileal digestibility of methionine was not affected by dietary protein source. Except for methionine, net disappearance of all amino acids in the small intestine, relative to the amount fed, was higher for the SBM diet than for the CM diet. Net disappearance or synthesis of amino acids in the large intestine were not affected by dietary protein source. Similarly, dietary protein source did not affect (P greater than .05) the secretion of pancreatic juice or concentrations of protein, chymotrypsin and trypsin in pancreatic juice. Soybean meal protein has higher ileal and total gastrointestinal tract digestibility than CM protein for young, growing calves.     

In situ ruminal degradability and intestinal digestion of raw and extruded legume seeds and soya bean meal protein

An experiment was performed to evaluate the effect of extrusion and carbohydrate addition on rumen degradation and intestinal digestion of raw legume seeds and solvent extracted soya bean meal (SBM) protein. Whole soya beans (WSB) without or with maize added (75:25) (WSB-M), peas, lupins and SBM were extruded at 140 degrees C. Protein rumen degradation and intestinal digestibility of unprocessed and extruded protein sources were measured by in sacco and mobile bag procedures, respectively, in two dairy cows cannulated in rumen and duodenum. Between 12 and 15 polyester bags with 4 g of each protein source were incubated in rumen for 12 h and the residues, pooled by feed, were introduced into the duodenum in small nylon bags after pre-incubation in a pepsin solution, and recovered from faeces the day after. Extrusion significantly (p < 0.001) reduced N degradation of all protein sources, from 98.1%, 91.6%, 90.5% and 64.8% to 53.1%, 73.8%, 70.3% and 44.2% for peas, lupins, WSB and SBM respectively. The addition of maize to WSB strengthened the effect of extrusion on rumen N degradation, from 88.2% to 52.6%. Residues from rumen incubation of extruded feeds showed a higher (p < 0.001) intestinal N digestibility except for SBM (87.0%, 82.9%, 66.3%, 85.0% and 97.2%, and 99.1%, 95.8%, 96.8%, 97.8% and 98.7%, respectively, for non-extruded and extruded, peas, lupins, WSB, WSB-M and SBM). In conclusion, the extrusion of studied legume seeds and SBM promotes a clear and significant increase of their metabolizable protein value, particularly in peas, and the inclusion of a source of carbohydrates before extrusion increase this response.     

Effect of recombinant porcine somatotropin and dietary protein on pancreatic digestive enzymes in the pig.

This study was conducted to determine the effect of daily recombinant porcine somatotropin (rpST) injection (0 or 120 micrograms/kg BW) and dietary CP level of the feed (14 or 26% CP) on pancreatic characteristics of growing pigs. Daily injection of rpST did not affect pancreatic weight (P = .885) but did decrease pancreatic amylase content (P = .005). The ratios of amylase:protein and amylase:trypsin were also lowered by daily rpST injection (P = .002 and P = .0002, respectively). There were protein x rpST and protein x rpST x sex interactions for the ratio of amylase:chymotrypsin. The CP content of the diet had a greater effect than the injection of rpST on pancreatic characteristics. Pigs consuming the 26% CP diet had significantly higher pancreatic weight (P = .003) and greater total pancreatic chymotrypsin (P = .006) than pigs consuming the 14% CP diet. The ratios of trypsin and chymotrypsin to DNA were also higher in pigs fed the 26% CP diet (P = .007 and P = .005, respectively). These responses were not influenced by sex. Recombinant porcine somatotropin seemed to have a slight effect on porcine pancreatic characteristics; however, dietary protein had a greater effect on pancreatic characteristics in market-weight hogs.     

蛋氨酸对幼建鲤生长及消化吸收功能的影响

选择体重为(12.34±0.02)g健康建鲤864尾,平均分成6组,每组设3个重复,每个重复48尾。6个处理组分别饲喂蛋氨酸水平为0.39%、0.70%、1.00%、1.30%、1.60%和1.90%的饲料,试验期60 d。结果表明:饲料中蛋氨酸水平显著(P<0.05)或极显著(P<0.01)影响幼建鲤增重、摄食量、饲料系数、蛋白、脂肪和灰分沉积率;饲料蛋氨酸水平对组织谷-草转氨酶活力、血氨浓度也有极显著影响(P<0.01);饲料蛋氨酸水平显著(P<0.05)或极显著(P<0.01)影响幼建鲤肝胰脏重、肝胰脏蛋白含量、肠重、肠长、肠蛋白含量、肠皱襞高度、肠道和肝胰脏蛋白酶活力、脂肪酶活力、肠碱性磷酸酶活力、肠Na+,K+-ATPase活力。试验结果说明,蛋氨酸可促进幼建鲤消化器官生长发育、提高消化酶活性、增强吸收能力、从而提高生产性能。     

Effects of coextrusion of flaxseed and field pea on the digestibility of energy, ether extract, fatty acids, protein, and amino acids in grower-finisher pigs

The objectives of this study were to determine the ileal and total tract digestibility of individual fatty acids, ether extract, energy, protein, and AA in a mix of flax and field pea (FP) and to determine whether extrusion improves the nutritive value of this mix. Five barrows (23-kg initial BW) fitted with a T-cannula at the distal ileum were fed 5 diets at 3 times the maintenance energy requirement according to a 5 x 5 Latin square design: a wheat and soybean meal control diet and 4 diets containing 30% raw or coextruded FP plus 70% control diet and chromic oxide as an indigestible marker. The 4 extrusion treatments included the following: 1) FP0, ground, nonextruded; 2) FP1, single-screw extruded; 3) FP2, twin-screw extruded with low intensity (screw speed 120 rpm; die temperature 110 degrees C; water input 5 kg/h); and 4) FP3, twin-screw extruded with high intensity (300 rpm; 125 degrees C; 11 kg/h). The ether extract concentration was 17.8, 19.6, 17.7, and 17.3% (as fed) in FP0, FP1, FP2, and FP4, respectively. The ADF concentration was 13.2, 11.1, 11.4, and 13.7% (as fed) in FP0, FP1, FP2, and FP4, respectively. After a 7-d acclimation, feces were collected for 2 d, and then ileal digesta was collected for 2 d. Energy digestibility in the test ingredients was calculated using the difference method. Extrusion of FP did not affect the apparent total tract digestibility (ATTD) and apparent ileal digestibility (AID) of DM, OM, and CP for grower-finisher pigs. Extrusion increased (P < 0.05) the ATTD of GE and ether extract and the DE content of FP, and the AID of the Arg, Ile, Leu, Lys, Phe, Thr, and Val, and total fatty acids. Extrusion tended to increase (P < 0.10) the AID of linolenic acid. Single-screw extrusion resulted in a greater (P < 0.05) ATTD of GE, OM, ether extract, and DE content of FP and AID of SFA than twin-screw extrusion. Single-screw extrusion resulted in a trend for greater (P < 0.10) AID of linolenic acid and total fatty acids than twin-screw extrusion. Twin-screw extrusion at high intensity resulted in less (P < 0.05) AID of SFA than twin-screw extrusion at low intensity, indicating that equipment and conditions should be carefully controlled for the extrusion of FP. In conclusion, coextrusion of FP increased digestibility of ether extract, fatty acids, energy, and AA.     

饲料中添加缩合单宁对凡纳滨对虾生长性能、体成分、血清生化及抗氧化指标的影响

本试验旨在研究饲料中添加缩合单宁对凡纳滨对虾生长性能、体成分、血清生化及抗氧化指标的影响。选择初体重约为1.38 g的凡纳滨对虾600尾,随机分为5组,每组3个重复,每个重复40尾。5组对虾投喂缩合单宁添加量分别为0 (CT0组,作为对照组)、0.5 (CT0.5组)、1.0(CT1组)、2.0(CT2组)、4.0 g/kg DM(CT4组)的5种等氮等脂试验饲料,试验期56 d。结果表明：随着饲料中缩合单宁添加量的增加,凡纳滨对虾的终末体重、增重率和特定生长率呈线性增加的趋势(0.050.05)。饲料中添加缩合单宁对凡纳滨对虾体成分、肌肉氨基酸含量和血清生化指标均未产生显著影响(P>0.05)。与CT0组相比,饲料中添加1.0～2.0 g/kg DM缩合单宁显著增加了血清过氧化氢酶和超氧化物歧化酶活性(P<0.05),显著降低了血清丙二醛含量(P<0.05)。CT4组凡纳滨对虾血清过氧化氢酶和超氧化物歧化...