Nutritional value of waxy barleys for broiler chickens

Winter wheat was compared with a barley which has a normal amylopectin/amylose starch ratio, and waxy barleys which have essentially 100% amylopectin starch. In one trial, broiler chicks were fed on one of seven diets which had grain portions of all wheat (100W), 50% wheat–50% Compana (normal) barley (50W–50C), 25% wheat–75% Compana (25W–75C), 100% Compana (0W–100C), 50% wheat–50% Wapana (waxy) barley (50W–50Wa), 25% wheat–75% Wapana (25W–75Wa), or 100% Wapana (0W–100Wa). Body weights (g) at 7 weeks were (100W) 1659, (50W–50C) 1523, (25W–75C) 1401, (0W–100C) 1396, (50W–50Wa) 1503, (25W–75Wa) 1403 and (0W–100Wa) 1293. Dressing percentage was not affected by diet but mortality was greater on 0W–100C. Metabolizable energy (kJ/g dry matter) values determined on non-laying Leghorn hens were 12.93 ± 0.38 and 12.76 ± 0.46 for the Compana and Wapana barley, respectively. In a second trial, addition of a food-grade diastase at 2 g per kg of feed did not affect body weight on wheat-based diets, increased weights over corresponding control diets for Wapana-based diets but gave inconsistent results for Washunopana, a hull-less waxy barley with an active α-amylase-like activity on the starch granules. Group feed values indicated that enzyme supplements improved feed efficiency for barley diets but metabolizable energy values were similar for diets with or without diastase additions.     

Effect of avilamycin and tylosin on the metabolizable energy in growing and finishing pigs

In two metabolism trials with growing and finishing pigs the influence of the antibiotic feed additives Avilamycin and Tylosin on the metabolizable energy was investigated at different levels of dietary protein content. In the first experiment (growing pigs) the antibiotics were supplied at levels of 0 mg/kg, 40 mg/kg Avilamycin and 40 mg/kg Tylosin to diets containing 18.5%, 17.5%, 16.5% and 14.0% of crude protein. In the second experiment (finishing pigs) 0 mg/kg antibiotics, 20 mg/kg Avilamycin and 20 mg/kg Tylosin were used in diets containing 16.5% and 14.0% of crude protein. The body weight of the animals averaged 46 kg (growing pigs) and 68 kg (finishing pigs).

In growing pigs the supplementation of Tylosin increased the digestibility of dry matter and energy at 1 percentage unit each, while in finishing pigs no effects were observed. Since the urinary energy excretion was not affected by antibiotics, there was only in Tylosin treated growing pigs a slight rise in dietary contents of metabolizable energy by 1.6%. The reduction of the dietary protein content resulted in increased digestibility of dry matter and energy, reduced urinary energy excretions and increased dietary contents of metabolizable energy.     

Effects of deoxynivalenol (DON) on growth performance, nutrient digestibility and DON metabolism in pigs

Wheat infected naturally withFusarium, contaminated mainly with 18.53 mg DON per kg, was added to a total constant wheat proportion of 400g/kg diet. Control and DON contaminated feed was fed for 11 weeks underad libitum and restrictive feeding conditions to 48 pigs of both sexes, which were randomly divided into 4 groups. Effects on performance (live weight range between 26 and 100kg), duration of feed intake and blood parameters were investigated. Parallel to this study, a balance study was carried out to examine the effects on nutrient digestibility and DON metabolism. The group fed the DON contaminated rationad libitum consumed 15% less feed and gained 14% less live weight compared to thead libitum control group, while the feed to gain ratio was unaffected. Under restrictive feeding conditions (DON and control) pigs exhibited 33%, 25% and 10% lower feed consumption, live weight gain and feed to gain ratio, respectively, than the control group fedad libitum. Metabolizability of energy, digestibility of organic matter, crude protein, crude fat and N-retention were significantly increased by 4, 3, 6, 11 and 10%, respectively, in the DON group of the restrictively fed pigs. In average up to 43.2% of the ingested DON, as the parent toxin in both groups, was eliminated with the urine and up to 3.0% with faeces. DON fed animals needed more time to consume the restrictive ration than the control group. Presented at the 26^th Mykotoxin-Workshop in Herrsching, Germany, May 17–19, 2004. Financial support Deutsone Forschungsgemeingschaft     

Influence of different fibre sources on digestibility and nitrogen and energy balances in growing pigs

The present study was undertaken to investigate how three different fibre sources, sugar beet pulp, soya bean hulls and pectin residue, constituting 15% of diets for growing pigs, influenced daily body gain, feed conversion, apparent faecal digestibility and nitrogen and energy balances. Eight castrated crossbreed pigs (30-80 kg live weight) were used in a replicated 4 x 4 Latin-square design with one control diet and three fibre containing diets. Daily body weight gain and feed conversion were not affected by the dietary treatments. The apparent faecal digestibility of organic matter (OM) and energy were significantly lower for the fibre diets (OM: 0.81-0.85; energy: 0.78-0.83) compared to the control diet (OM: 0.88; energy: 0.86). The apparent faecal digestibility of crude protein (CP) was lower for the fibre diets (0.71-0.78) compared to the control diet (0.83), although it was only significantly lower for the sugar beet pulp and pectin residue diets. The pectin residue diet, which contained the highest amount of dietary fibre, lignin and insoluble non-starch polysaccharides, had the lowest digestibility of OM, CP and energy. There was a tendency (p = 0.07) for a diet effect on retained nitrogen in proportion to digested nitrogen, where the sugar beet pulp and pectin residue diets had numerically the highest values. Heat production and retained energy in proportion to metabolizable energy intake were not affected by fibre inclusion. It was concluded that the inclusion of sugar beet pulp, soya bean hulls and pectin residue in diets for growing pigs decreased the apparent faecal digestibility and in the diets with sugar beet pulp and pectin residue higher utilization of digested nitrogen for retention compensated for the lower amount of digested nitrogen.     

Effects of graded levels of Fusarium toxin contaminated wheat in diets for fattening pigs on growth performance, nutrient digestibility, deoxynivalenol balance and clinical serum characteristics

A dose response study was carried out with pigs in order to examine the effects of increasing dietary deoxynivalenol (DON)-concentrations on performance, clinical serum characteristics, nutrient digestibility and DON-metabolism. For this purpose, wheat contaminated naturally with Fusarium toxins was incorporated into pig diets at increasing proportions to give calculated dietary DON-concentrations of 0, 2.3 and 4.6 mg/kg during the starter period of phase 1 (14 d) of the experiment, and 0/0, 1.2/1.4, 2.3/3.7 mg/kg starter/grower diet during phase 3 (56 d) of the experiment. Each diet was tested on 16 pigs of both sexes with an initial average live weight of approximately 28 kg. A recovery phase (phase 2, 21 d) was intercalated between phase 1 and 3 of the growth experiment where all groups were fed with the uncontaminated control diet since some pigs exposed to the highest dietary DON-concentration during phase 1 nearly completely refused the offered feed. Affected pigs completely recovered during this phase. In phase 3, when diets with lower DON-concentrations were fed, no differences in performance could be detected. Serum clinical characteristics (enzymes indicating liver damage, total protein, immunoglobulins) did not respond to increasing DON-concentration in the diets. DON-concentration in serum increased in a dose-response-related manner as dietary DON-concentration increased. However, this parameter was not or only weakly correlated to any of the examined performance parameters or serum characteristics. Also, nutrient digestibility of the diets and N-retention were not affected by treatments with the exception of crude fat digestibility which was not consistently influenced. Concentration of DON and its metabolite de-epoxy-DON increased in urine with increasing dietary DON-concentration in a strongly linearly related fashion. The proportion of the excretion of de-epoxy-DON of the total urinary excretion of DON plus de-epoxy-DON rose linearly up to approximately 4%. Total recovery of DON plus de-epoxy-DON as percentage of DON-intake varied between 45 and 57% and was not influenced by dietary DON-concentration. Only a very small fraction of approximately 0.1% of ingested DON was recovered in faeces.     

Simultaneous inclusion of sorghum and cottonseed meal or millet in broiler diets: effects on performance and nutrient digestibility

Two experiments were conducted to investigate the use of sorghum, cottonseed meal and millet in broiler diets and their interaction when they are used simultaneously. In Experiment 1, a corn-soybean meal control diet was compared with eight experimental treatments based on low tannin sorghum (S30, S45 and S60), cottonseed meal (CM15, CM40) or both ingredients included in the same diet (S30/CM40, S45/CM25 and S60CM15). Results showed that BW gain was not affected by the inclusion of sorghum or cottonseed meal. However, feed intake tended to be affected by the cereal type with the highest values with sorghum-based diets. Feed conversion ratio increased (P<0.001) with sorghum-based diets compared with the control diet, whereas a combination of cottonseed meal and sorghum in the same diet did not affect the feed conversion ratio. Significant differences (P<0.001) were observed in apparent ileal digestibility (%) of protein and energy with the cottonseed meal and sorghum/cottonseed meal-based diets having lower protein and energy digestibility compared with corn-based diets. In Experiment 2, a control diet was compared with six diets in which corn was substituted at 60%, 80% or 100% by either sorghum or millet and other three diets with simultaneous inclusion of these two ingredients (S30/M30, S40/M40, S50/M50). Single or combined inclusion of sorghum and millet resulted in similar feed intake and growth performance as the control diet. Apparent ileal digestibility of protein and energy was higher with millet-based diets (P<0.001). Total tract digestibility of protein in sorghum and millet-based diets tended to decrease linearly with the increasing level of substitution. Sorghum-based diets resulted in lower total tract digestibility of fat compared with millet and sorghum/millet-based diets (P<0.001). Higher total tract digestibility of starch were obtained with the control diet and millet-based diets compared with the sorghum-based treatments. Results of the two experiments suggest that broiler growth performance was not affected by the dietary level of sorghum, millet or cottonseed meal. Nutrient digestion can, however, be affected by these feed ingredients.     

Increasing levels of rapeseed expeller meal in diets for pigs: effects on protein and energy metabolism

The heavy reliance on imported soybean meal (SBM) as a protein source makes it necessary for the European pig industry to search for alternatives and to develop pigs that perform efficiently when fed such ingredients. Digestion and metabolism are major physiological processes contributing to variation in feed efficiency. Therefore, an experiment was conducted to assess the effects of replacing SBM with increasing levels of rapeseed meal (RSM) in diets for young pigs on apparent total tract digestibility (ATTD) of energy and nutrients, nitrogen (N) balance, energy metabolism and carbohydrate, protein and fat oxidation. Four diets were fed to 32 pigs (22.7±4.1 kg initial BW) for three weeks. The diets consisted of a control cereal grain-SBM basal diet and three test diets where SBM and wheat were partially replaced with 10%, 20%, and 30% of expeller RSM. Increasing level of RSM in the diets linearly reduced ATTD of organic matter, CP, total carbohydrates, dietary fiber and energy. Utilization of digested nitrogen (DN) for N retention and total N excretion were not affected by RSM inclusion, however, RSM inclusion induced a shift in N excretion from urine to feces. Despite a linear increase in liver to metabolic BW ratio, heat production and utilization of metabolizable energy (ME) for retention were not affected by increasing RSM inclusion. In conclusion, replacing SBM with up to 30% of expeller RSM in nutritionally balanced diets for young pigs reduced the ATTD of most nutrients and energy, but did not affect N and energy retention in the body or efficiency of utilization of DN or ME for retention.     

Influence of different fibre sources on digestibility and nitrogen and energy balances in growing pigs

Abstract

The present study was undertaken to investigate how three different fibre sources, sugar beet pulp, soya bean hulls and pectin residue, constituting 15% of diets for growing pigs, influenced daily body gain, feed conversion, apparent faecal digestibility and nitrogen and energy balances. Eight castrated crossbreed pigs (30 – 80 kg live weight) were used in a replicated 4 × 4 Latin-square design with one control diet and three fibre containing diets. Daily body weight gain and feed conversion were not affected by the dietary treatments. The apparent faecal digestibility of organic matter (OM) and energy were significantly lower for the fibre diets (OM: 0.81 – 0.85; energy: 0.78 – 0.83) compared to the control diet (OM: 0.88; energy: 0.86). The apparent faecal digestibility of crude protein (CP) was lower for the fibre diets (0.71 – 0.78) compared to the control diet (0.83), although it was only significantly lower for the sugar beet pulp and pectin residue diets. The pectin residue diet, which contained the highest amount of dietary fibre, lignin and insoluble non-starch polysaccharides, had the lowest digestibility of OM, CP and energy. There was a tendency (p = 0.07) for a diet effect on retained nitrogen in proportion to digested nitrogen, where the sugar beet pulp and pectin residue diets had numerically the highest values. Heat production and retained energy in proportion to metabolizable energy intake were not affected by fibre inclusion. It was concluded that the inclusion of sugar beet pulp, soya bean hulls and pectin residue in diets for growing pigs decreased the apparent faecal digestibility and in the diets with sugar beet pulp and pectin residue higher utilization of digested nitrogen for retention compensated for the lower amount of digested nitrogen.     

Influence of dietary fibre level and pelleting on the digestibility of energy and nutrients in growing pigs and adult sows

Two experiments were carried out to investigate the effect of pelleting on the apparent total tract digestibility (ATTD) of energy and nutrients according to the dietary fibre (DF) level in growing pigs (experiment 1) and in adult sows (experiment 2). Four diets based on wheat, barley, maize and soybean meal and supplemented with increased contents of a mixture of wheat bran, maize bran, soybean hulls and sugar beet pulp (116, 192, 268 and 344 g NDF/kg dry matter (DM) in diets 1 to 4) were tested. In experiment 1, 32 growing pigs (62 kg average BW), in two replicates and according to a factorial design, were fed one of the four diets, either as mash or as pellets. The digestibility of energy, organic matter (OM) and all nutrients decreased with DF increasing for both feed forms; the reduction was about 1% for each 1% NDF increase in the diet (P < 0.001). Pelleting improved moderately the digestibility of energy and OM (+1.5% and +1.0%, respectively; P < 0.05) in connection with greater DF (+5%; P < 0.05) and fat digestibility (+25%). Thus, pelleting improved the digestible energy content of diets on average by 0.3 MJ/kg of feed DM (P < 0.01). In experiment 2, four adult dry sows (235 kg average BW) were used in a 4 × 4 Latin square design and fed the four diets used in experiment 1 as pellets. The digestibility of energy, OM and macronutrients also decreased with DF increase (P < 0.001; -0.4% per 1% increase of dietary NDF for energy) while the digestibility of DF (i.e. crude fibre (CF) or ADF) increased (P < 0.001) or remained at a high level. In conclusion, increasing DF in diets decreases the digestibility of nutrients and energy in pigs and in sows. Although positive, the pelleting impact is minor on the energy and nutrients digestibility of fibre-rich diets in growing pigs, even in high-DF diets.     

Fütterungseinfluss von Deoxynivalenol-belastetem Weizen bei Ferkeln

Effects of the mycotoxin deoxnivalenol (DON) on weaned piglets were investigated. Two feeding trials were conducted with naturally contaminated wheat in the ration. In the first trial as preliminary study weaned piglets were fed for one week with 7.7 mg DON per kg ration, intake of DON contaminated diets was not associated with any obvious negative health effects. Also in the main feeding trial with 3 mg DON per kg ration no vomiting and other negative clinical symptoms could be registered. The feed intake and the daily weight gains were significantly lower in the DON fed group when compared with control group, but the feed conversion rates were slightly improved in group fed DON.

Presented at the 25^th Mykotoxin Workshop in Giessen, Germany, May 19–21, 2003     

Effect of increasing inclusion rates of tofu by-product in diets of growing pigs on nitrogen balance and ammonia emission from manure

To reduce competition with human-edible feed resources, it is of interest to incorporate by-products from the food industry in animal feeds. The current research investigated the effect of including increasing amounts of tofu by-product (TF) in practical pig diets on animal performance, nitrogen balance and ammonia emissions from manure. Two experiments were conducted including a control diet without TF, containing 160 g/kg dietary non-starch polysaccharides (NSPs) and three diets including 122, 246 and 360 g TF/kg DM (TF122, TF246 and TF360, respectively) to reach 220, 280 and 360 g/kg NSP. All diets had the same level of CP and protein digestible in the small intestine which particularly was realized by replacing rice bran with TF. Animal performance was assessed in a first experiment with 40 growing barrows with initial BW of 26.6 ± 1.80 kg (M ± SD) being allocated to the 4 treatments, during 2 growth phases (i.e. until 50 kg BW and from 50 to 80 kg BW). In the growth phase until 50 kg, feed intake and average daily gain (ADG) were linearly reduced by dietary TF inclusion, while this negative impact disappeared during the second growth phase (50 to 80 kg BW). Tofu by-product inclusion even positively affected the feed conversion ratio during this second growth phase (3.4 to 2.7 kg feed/kg ADG for 0 to 360 g/kg dietary TF). Over the entire growth period, performance and feed intake were negatively affected at the highest dietary TF level. Experiment 2 was conducted to assess digestibility, nitrogen balance and ammonia emission from manure. For this purpose, 16 pigs with BW of 62.8 ± 3.6 kg (M ± SD) were assigned to either 1 of the 4 treatments. There was no difference in total tract apparent digestibility of dietary organic matter or CP, while NDF digestibility increased with increasing TF level, suggesting increasing importance of the hindgut fermentation when digesting diets with increasing TF levels. Nevertheless, this was not reflected in increasing levels of faecal volatile fatty acids or purines, nor in reduced manure pH. As a result, ammonia emission from slurry was not reduced through dietary TF inclusion, despite the linear decrease in urinary nitrogen. In conclusion, TF can be included in pigs’ diets up to an inclusion rate of 25% without risk of impaired animal performance; however, this dietary strategy fails to mitigate ammonia emission from slurry.     

Potential use of high levels of vegetal proteins in diets for market-sized gilthead sea bream (Sparus aurata)

The effect of partial or total dietary substitution of fishmeal (FM) by vegetal protein sources on growth and feed efficiency was carried out in on-growing gilthead sea bream (mean initial weight 131 g). The Control diet (FM 100) contained FM as the primary protein source, while in Diets FM 25 and FM 0 the FM protein was replaced at 75% and 100%, respectively, by a vegetable protein mixture consisting of wheat gluten, soybean meal, rapeseed meal and crystalline amino acids. Diets FM 25 and FM 0 also contained krill meal at 47 g/kg in order to improve palatability. At the end of the trial (after 158 d), fish survival was above 90%. Final weight and the specific growth rate were statistically lower in fish fed the Control diet (361 g and 0.64%/d), compared with 390–396 g and 0.69–0.70%/d after feeding vegetal diets. No significant differences were found regarding feed intake and feed conversion ratio. The digestibility of protein and amino acids (determined with chromium oxide as indicator) was similar in all diets. The blood parameters were not significantly affected by treatments. The activity of trypsin and pepsin was significantly reduced after feeding Diet FM 0. In the distal intestine, the villi length in fish fed Diet FM 25 was significantly longer and the intestine of the fish fed the FM 100 diet showed a smaller number of goblet cells. In conclusion, a total FM substitution by a vegetal mix supplemented with synthetic amino acids in on-growing sea bream is feasible.     

Performance of fattening cattle and lactating beef cows on diets high in chemically treated wheat straw and poultry litter

Three experiments were carried out to study the effect of chemical treatment on the nutritive value of wheat straw (WS) and the effect of diets containing such treated straw and poultry litter (PL) on the performance of fattening cattle and lactating beef cows. The chemical treatment consisted of treating half of the wheat straw with 60 kg sodium hydroxide/t and the other with 60 kg sulphuric acid/t, and then mixing the two to give “Celephos”. The digestibility coefficient of organic matter was 68.0 and 41.7 for “Celephos” and untreated straw, respectively.For a long term feeding trial, two mixtures were formulated: (a) including 23% WS and 19% PL; (b) including 30% chemically treated WS and 16% PL. A conventional high grain fattening diet (c) served as control. The metabolizable energy concentrations in the above diets were 2.37, 2.38 and 2.78 Mcal/kg DM. Protein content of the diets was regulated by PL or soya bean meal. Liveweight gain was 1059, 1137 and 1180 g/day, metabolizable energy conversion ratio to liveweight was 22.8, 20.7 and 20.0 Mcal/kg, and carcass gain was 565, 606 and 656 g/day for treatment groups (a), (b) and (c), respectively.In a third trial, lactating beef cows were fed on long straw or Celephos, PL and 1.5 kg grain per head per day. Intake of Celephos was 28% higher than that of untreated straw and milk output was 3 kg/day higher. This was reflected in an increase of 67 g/day in gain of suckled calves.     

Proper energy evaluation of commercial laboratory animal diets based on digestibility and metabolizable energy values

The energy values of commercial laboratory animal diets have been customarily calculated by applying physiological fuel values (PFV) in this country. In order to ascertain accuracy of this application, apparent digestibility of crude protein, crude fat, nitrogen-free extracts (NFE), carbohydrate (NFE + crude fiber) and nitrogen-corrected metabolizable energy (MEn) of 10 commercial diets were determined using rats, dogs, rabbits and guinea pigs, respectively, and true digestibility of crude protein and crude fat of 12 feed ingredients was determined using rats. Apparent digestibility of the nutrients in the diets decreased with an increase in the crude fiber content of the diets. MEn values of the diets ranged between 2.18 and 3.75 kcal per g dry matter depending upon the crude fiber content of the diets. The energy values of the 10 diets calculated using PFV values of 4 kcal/g for protein and carbohydrate and 9 kcal/g for fat were compared with each MEn. The calculated values were 1.04 to 1.39 times higher than those of the respective MEn. All of the diets and most feed ingredients did not show high digestibility of nutrients assumed for the application of PFV. Therefore, it is concluded that application of PFV to the diets results in over-estimation of energy values and use of PFV for commercial laboratory diets in our country is not warranted. It is advisable to use MEn to evaluate energy value of commercial laboratory animal diets.     

Energetics in Atlantic salmon (Salmo salar L.) parr fed elevated dietary cadmium

Atlantic salmon (Salmo salar L.) parr were reared for 4 months on experimental diets supplemented with Cd (0.5, 5, 25, 125, or 250 mg Cd x kg(-1)) to assess the long-term energetic changes based on the digestibility and biochemical deposition of the major dietary nutrients and to evaluate a maximum tolerable dietary toxicant concentration. Growth did not differ significantly (P>0.05) from the control groups. The biochemical composition of the carcass, but not the viscera, was negatively affected by dietary Cd exposure. The significant decreases in protein, lipid, and glycogen concentrations in the carcass (P<0.05, 25 mg x kg(-1) compared to control groups) caused a reduction in calculated whole-body energy content in fish fed 125 mg x kg(-1)compared to control groups. This reduction in calculated whole-body energy content was explained by a concurrent significant disturbance to the gastrointestinal function (measured as reduced digestibility). Only at the highest dietary Cd exposure (250 mg x kg(-1)), increased metabolic costs to cope with Cd toxicity was thought to contribute significantly to the reduction in carcass energy content. The most important factor effecting calculated total energetics was nutrient digestibility. Based on the logarithmic effective median concentration for reduced calculated energy digestibility (dietary Cd concentration corresponding to 50% reduction, EC50), the maximum tolerable dietary Cd concentration is 11 mg x kg(-1) diet.     

Effect of high fibre diets formulated with different fibrous ingredients on performance,nutrient digestibility and faecal microbiota of weaned piglets

The aim of the experiment on 180 weaned piglets (8.9 kg body weight) was to investigate the influence of high fibre diets formulated with different fibrous ingredients on performance, nutrient digestibility, diarrhoea incidence and numbers of faecal microbiota. The dietary treatments included a Control diet and five high fibre diets formulated with different fibre sources including wheat bran, soybean hulls, naked oat hulls, palm kernel expeller and bamboo fibre. The high fibre diets averaged 14.6% neutral detergent fibre with different non-starch polysaccharides (NSP) components and were fed ad libitum for 28 d. Faecal samples were collected during the last 3 d of the experiment and the apparent total tract digestibility of nutrients and fibre components were determined. Pigs fed the Control and wheat bran diets had a higher (p ≤ 0.05) average daily gain (ADG) than pigs fed the palm kernel expeller and bamboo meal diets. The reduced ADG for pigs appeared to be related to reductions in the digestibility of gross energy and dry matter, respectively. The feed-to-gain ratio was significantly higher (p ≤ 0.05) for pigs fed the fibre diets. The digestibility of NSP components was different among the treatments. The diarrhoea incidence was not affected by treatments. The abundance of faecal bifidobacteria was significantly higher (p ≤ 0.05) for pigs fed the wheat bran diet than for pigs fed the bamboo meal diet. It was concluded that the diets formulated with different fibre sources when fed to weaned piglets have different effects on pig performance, nutrient digestibility and numbers of faecal microbiota. The wheat bran diet rich in arabinoxylans enabled a better performance than the other tested diets with fibre addition.     

The potential effects of antioxidant feed additives in mitigating the adverse effects of corn naturally contaminated with <Emphasis Type="Italic">Fusarium</Emphasis> mycotoxins on antioxidant systems in the intestinal mucosa,plasma, and liver in weaned pigs

Seventy-two piglets (6.0 kg BW) were randomly distributed within six different dietary treatments to evaluate the effect of deoxynivalenol (DON) and the potential of four antioxidant feed additives in mitigating the adverse effects of DON on growth performances and oxidative status. Dietary treatments were as follows: control diet 0.8 mg/kg DON; contaminated diet (DON-contaminated diet) 3.1 mg/kg DON; and four contaminated diets, each supplemented with a different antioxidant feed additive, DON + vitamins, DON + organic selenium (Se)/glutathione (GSH), DON + quercetin, and DON + COMB (vitamins + Se/GSH + quercetin from the other treatments). Although DON was the main mycotoxin in the contaminated diet, this diet also contained 1.8 mg/kg of zearalenone (ZEN). The “mycotoxin” effects therefore included the combined effect of these two mycotoxins, DON, and ZEN. The DON-ZEN ingestion did not affect growth performances, average daily gain (ADG), average daily feed intake (ADFI), and feed efficiency (G:F ratio), but partially induced oxidative stress in weaned pigs as shown by increased malondialdehyde (MDA) content in the plasma and superoxide dismutase (SOD) activity in liver (P?<?0.05). However, no change in the activity of other antioxidant enzymes or GSH concentrations was observed in plasma and liver of piglets fed the DON-contaminated diet (P?>?0.05). Supplementation with individual antioxidant feed additive had a limited effect in weaned pigs fed DON-ZEN-contaminated diets. Combination of antioxidants (vitamins A, C, and E, quercetin, and organic Se/GSH) reduced plasma and liver MDA content and SOD activity in liver (P?<?0.05) of piglets fed DON-ZEN-contaminated diets. Furthermore, this combination also reduced MDA content in the ileum (P?<?0.05), although activity of glutathione peroxidases (GPx), SOD or catalase (CAT) in the ileum was not affected by DON-ZEN contamination or antioxidant supplements. In conclusion, DON-ZEN contamination induced oxidative stress in weaned pigs and combination of antioxidant feed additives restored partially the oxidative status. Further studies will be necessary to assess whether the effects of antioxidant feed additives on oxidative status are specific when feed is contaminated with DON-ZEN.     

Effects of inclusion with blue lupins (Lupinus angustifolius) in broiler diets and enzyme supplementation on production performance, digestibility and dietary AME content

An experiment with broiler chickens was conducted to study the effect of inclusion of blue lupins and exogenous enzyme to broiler diets on the apparent metabolisable energy (AME), digestibility and performance. Two basal diets were formulated: a non-lupin diet A based on soya bean meal and maize, and a diet B where parts of soya bean meal and maize were substituted with blue lupin (200 g/kg). The two basal diets were fed either alone or, for diet B in combination with different enzyme preparations (Bio-Feed Plus, lactase, two galactanases (Gal-I and Gal-II)). The experiment was performed in battery cages with 648 male broiler chickens, where eight experimental diets were fed to the chickens from 7 to 21 days of age and weight gain and feed intake were measured during the period. At the end of the experiment, three chickens from each pen were slaughtered and the content from jejunum and ileum was separately collected and pooled and used for measurement on intestinal viscosity. For measurements of the apparent metabolisable energy and the apparent digestibility, excreta were collected at 22–24 days of age and ileal contents collected at 25–26 days from the remaining chickens.

Substitution of soya bean meal and maize with blue lupin depressed weight gain (9%) and feed conversion ratio (12%) significantly. Feed intake of the lupin-based diets was not decreased. The protein in lupin was digested to the same extent as the protein from soya bean meal, the coefficient of ileal apparent digestibility being on average 0.75. However, the high content of the non-starch polysaccharides (NSP; 450 g/kg) in lupin depressed the apparent digestibility of the organic matter by approximately 10%. The AME_n of the non-lupin diet was 14.01 MJ/kg dry matter (DM) compared to a value of 13.11 MJ/kg DM in the lupin control diet. Improvements in the measured parameters were seen with some of the enzymes. Gal-I, and Gal-II in combination with lactase were the most efficient enzymes concerning improvement in AME_n and performance. Weight gain was increased by 3.5–5.5% by addition with these enzymes. Gal-I increased the AME_n significantly to 13.65 MJ/kg, a value not significantly different from the AME_n of the non-lupin diet. There was no effect of addition with the different enzymes on the coefficients of apparent digestibility of organic matter measured in the ileum, whereas addition with Gal-I to the lupin diet increased the apparent digestibility of organic matter over the total tract by 3%. The mode of action of the galactanases has been to hydrolyse the galactan in the NSP cell wall of lupins to galactose and dimers of galactose, which are energy-yielding to poultry. From the results obtained, it can be indicated that Gal-I increased the energy utilisation of the lupin-based diet, confirmed by the improved AME_n content and performance.     

Banana meal for feeding pigs: digestive utilization,growth performance and feeding behavior

The main objective of the present work was to determine the nutritional value and the strategies of using green banana meal (BM) in growing pigs. Two trials involving a total of 96 growing pigs were designed to study the effect of the harvest stage on the nutritional and energy values of BM (trial 1) and to evaluate the consequence of feeding gradual levels of BM on growth performance and feeding behavior in growing pigs (trial 2). In trial 1, the digestive utilization of three diets including 40% BM were compared with a control (C) soybean meal-corn diet in two batches of 12 pigs. BM was obtained from fruits harvested at 750 degrees-days (DD; early harvesting stage), 900 DD (normal harvesting stage) and 1150 DD (late harvesting stage). In trial 2, 72 Large White pigs were grouped in pens of nine animals and were given ad libitum access to one of the four dietary treatments (two pens/diet) differing from the rate of inclusion of 900 DD BM (0%, 20%, 40%, 60%). The estimated energy apparent digestibility coefficients of BM increased with the harvest stage (75.5%, 80.7% and 83.2% for BM at 750, 900 and 1150 DD, respectively). Digestible energy and metabolizable energy values were higher for BM at 1150 DD (13.56 and 13.05 MJ/kg DM, respectively) than at 900 DD (13.11 and 12.75 MJ/kg DM, respectively) or at 750 DD (12.00 and 11.75 MJ/kg DM, respectively). In trial 2, average daily gain and feed conversion ratio were not affected (P>0.05) by the rate of BM inclusion (822 g/day and 2.75 kg/kg on average, respectively). Feed intake and feeding behavior parameters were not significantly influenced by the dietary treatments except for the rate of feed ingestion with a lower value for the diet with 40% of BM (27.4 v. 32.2 g/min on average; P<0.01) when compared with the other diets. Results of this study indicate that the energy value of BM increases with the harvest stage and that BM can be incorporated up to 60% in growing finishing pig diets.