Maize-soybean Meal Diet Research Articles

Digestive utilization of tropical foliages of cassava, sweet potatoes, wild cocoyam and erythrina in Creole growing pigs

Total tract digestive utilization of cassava (Manihot esculenta) leaves and leaves+stems, sweet potatoes (Ipomoea batatas) leaves and leaves+stems, cocoyam (Xanthosoma sagittifolium) leaves, and erythrina (Erythrina glauca) leaves was studied in three simultaneous Latin square designs with a total of nine castrated Creole growing pigs. Each dried foliage was included at 200g/kg in a basal maize-soybean meal diet (MSBM) and the difference method was used to calculate the nutritional value of each of the six foliages. These leaves were characterized by a high fibre content and the presence of some anti-nutritional factors (such as tannins, 0.8–3.1%). Each of the foliage diets was measured on three animals (nine for the MSBM diet). Rate of passage variables of diets were also determined using a pulse dose of ytterbium. Mean retention time in the gastrointestinal tract was shorter (P<0.01) for diets including tropical foliages (30.4h vs. 42.1h for the MSBM diet) and shorter for the two cassava diets than for the other diets (26.8h vs. 32.2h on average; P<0.05). The total tract apparent digestibility coefficient (CTTAD) of dietary energy was reduced (P<0.01) by the inclusion of tropical foliages (−0.098 on average). Similar results were observed for dietary crude protein (CP) (−0.143 on average; P<0.05), except for the cocoyam diet that did not differ from the MSBM diet. For cassava and sweet potatoes, the addition of the stems to the leaves did not affect CTTAD of CP and energy. According to the difference method, the CTTAD was −0.328, 0.112, 0.212 and 0.647 for CP and 0.266, 0.310, 0.434 and 0.466 for energy and the corresponding digestible energy contents were 5.21, 6.22, 7.47 and 8.37MJ/kg DM for erythrina, cassava, sweet potatoes and cocoyam leaves, respectively. The inclusion of the stem to the leaves fractions did not affect digestibility of energy and nutrients (P>0.05) for cassava and sweet potatoes. It is concluded that the high fibre content in addition to the presence of tannins are the main limiting factors of these tropical foliages in pig nutrition with a subsequent low energy value.

Effects of Dietary Thermostable Phytase Supplementation on Growth Performance and Ca and P Metabolism of Broilers.

A study was conducted to study the effects of thermostable phytase supplementation on the growth performance and Ca and P metabolism of broilers for 21 d. 1-day-old Arbor Acres chicks with similar initial body weight were randomly divided into 3 treatments consisting 8 pens of 10 chicks per pen. The control group was given maize-soybean meal basal diet, and the other two groups were fed the basal diet including either 500 U ordinary phytase/kg diet or 500 U thermostable phytase/kg diet. The results indicated that broilers given diets supplemented with phytase have enhanced body weight and weight gain when compared with these fed basal diet (P 0.05). Dietary phytase supplementation significantly decreased fecal P excretion (P 0.05). The results indicated that dietary phytase supplementation can improve growth performance and metabolic status of P, and these effects appeared to be more pronounced in the thermostable phytase-supplemented group.

Comparative effects of nano elemental selenium and sodium selenite on selenium retention in broiler chickens

Two experiments were performed to explore the selenium retention of Nano elemental selenium (Nano-Se) in Arbor Acre male broiler chickens as compared with sodium selenite. A 2×4 factorial arrangement with 0.15, 0.30, 0.60 and 1.20mg/kg dietary Se from Nano-Se or sodium selenite added to a maize–soybean meal diet was conducted to study the effects of Se source and level on growth performance, serum glutathione peroxidase (GSH-Px) activity, Se concentration in serum and tissue. Furthermore, selenium retention of Nano-Se and selenite was determined in chicks by the oral or intravenous administration of the radiolabeled Se and the in vivo ligated intestinal loop procedure. As for selenite, average daily gain (ADG), gain/feed and survival ratio reached a plateau at the Se concentration of 0.15–0.30mg/kg and then declined as supplemental selenite increased. As for Nano-Se, ADG, gain/feed and survival ratio reached a plateau at the Se concentration of 0.15–1.20mg/kg. Survival ratio, ADG and gain/feed increased quadratically (P<0.05) as dietary selenite increased (P<0.05), and increased linearly and quadratically (P<0.05) as dietary Nano-Se increased (P<0.05). Selenium concentrations in serum, liver and breast muscle increased linearly and quadratically (P<0.05) as the dietary Se level increased for either Se source, but the magnitude of increase was substantially greater (P<0.05) when Nano-Se was fed. Retention of the orally or intravenously administered 75Se showed that the percentages of Nano-Se in the whole body and liver tissue were much higher (P<0.05) than those of selenite. Intestinal transport of 75Se from ligated loop to body showed that the transfer of Nano-Se from the intestinal lumen to the body was higher (P<0.05) than that of selenite, while the intestinal retention of Nano-Se was lower (P<0.05) than that of selenite. The results showed that the range between optimal and toxic dietary levels of Nano-Se was wider than that of sodium selenite, and Nano-Se was more efficiently retained in the body than sodium selenite.

The effect of peppermint essential oil and fructooligosaccharides, as alternatives to virginiamycin, on growth performance, digestibility, gut morphology and immune response of male broilers

With the increasing concerns over food safety during these years, there has been an intense effort for substituting (eliminating) antibiotic growth promoters in poultry feeds. Therefore, in order to investigate the effect of natural alternatives for antibiotics, an experiment was conducted to examine the effect of virginiamycin, a prebiotic (Fructomix), and peppermint (Mentha piperita) essential oil on productive performance, digestibility, intestinal morphology and immune response of broilers. A total of 240 Ross 308 male broilers were randomly (completely randomized design) allotted to five treatments, with four replicates per treatment (12 chickens per pen). Birds were offered either a maize-soybean meal basal diet (control, CON) or the basal diet supplemented with 200mg/kg virginiamycin (VM); 200mg/kg peppermint oil (PO1); 400mg/kg peppermint oil (PO2); or 500mg/kg Fructomix (FM). After 6 weeks, daily live weight gain and feed intake were higher (P<0.001) for VM-fed birds compared with other groups. Feed conversion ratio was better (P=0.039) in chicks fed the VM (1.74), and PO1 diet (1.75) compared with birds in the CON (1.84) and PO2 (1.86) groups. Primary antibody titers against sheep red blood cell were higher (P<0.001) in broilers fed FM (6.37) compared with other groups. At 21d of age, crude protein digestibility was higher (P=0.001) in PO1 group (0.8645) compared with other groups except VM (0.8505). Finally, higher ether extract digestibility (P=0.040) was detected in birds fed VM (0.8831) compared with PO2 (0.7940), and FM (0.7561) fed birds. In duodenum, villus height: crypt depth was higher (P=0.008) in VM supplemented group (7.07) in comparison with other groups. In conclusion, this study showed that neither PO nor FM could be suggested as effective alternative for VM.

Nutritional value of white lupins (Lupinus albus) for broilers: apparent metabolisable energy, apparent ileal amino acid digestibility and production performance

Two experiments were conducted to evaluate the nutritional value of three cultivars (Promore, Kiev mutant and Ultra) of white lupins (Lupinus albus L.) for broilers. In experiment 1, the apparent metabolisable energy (AME) and ileal amino acid digestibility coefficients of the three cultivars were determined. The cultivar effects were significant (P < 0.05) for AME, but the ileal amino acid digestibility coefficients were similar (P > 0.05) between cultivars. The AME value of Ultra cultivar was lower (P < 0.05) than those of Promore and Kiev mutant cultivars. In Experiment 2, using the AME and ileal digestible amino acid values determined in Experiment 1, diets containing 200 g/kg of lupin were formulated and the effects of feeding these diets on performance, digestive tract development and excreta quality of broiler starters were investigated. Weight gain, feed intake and feed per gain of broilers fed diets containing white lupins were similar (P > 0.05) to those fed the maize–soybean meal diet. The performance of birds fed diets containing different cultivars of white lupins was similar (P > 0.05). Several digestive tract parameters were influenced by the dietary inclusion of white lupins. In particular, the relative liver weight and the relative empty weights of small intestine and caeca in birds fed diets containing white lupins were higher (P < 0.05) than those fed the maize–soybean meal diet. No differences (P > 0.05) were observed in the excreta quality scores between the birds fed the maize–soybean meal diet and those fed diets containing white lupins.

Effect of enzyme preparation on egg production, nutrient retention, digestive enzyme activities and pancreatic enzyme messenger RNA expression of late-phase laying hens

This experiment was conducted to study the effect of dietary inclusion of an enzyme preparation including phytase, xylanase, cellulase, α-amylase and acidic protease on egg production, nutrient retention, digestive enzyme activities and pancreatic enzyme mRNA expression. Three hundred and sixty ISA Brown laying hens were randomly allocated to two groups with 6 replicates of 30 birds each and fed a maize–soybean meal diet with or without enzyme supplementation (ES) from 60 to 68wk of age. There were no differences in hen performance between the two groups. The coefficient of total tract apparent retention (CTTAR) of ether extract (EE) was increased (P<0.05) by ES. Birds fed the diet supplemented with enzymes tended to have higher lipase and protease activity in duodenal and jejunal digesta (P<0.10) than control birds. There were no significant effects of ES on pancreatic enzyme activities. The mRNA expression of amylase in pancreas tended to be downregulated by ES as compared with the control group (P=0.097), whereas that of pancreatic trypsinogen was not affected. It is concluded that ES did not affect productive performance of laying hens, but improved nutrient retention and tended to increase enzyme activities in the intestinal contents. The tendency for lower pancreatic amylase mRNA expression with ES, not coupled with a reduction in pancreatic enzyme activities suggests that amylase expression may be regulated not only at transcriptional level but also at post-transcriptional level.

Effect of dietary energy source on deposition and fatty acid synthesis in the liver of the laying hen

1. This experiment was conducted to determine the effect of different dietary energy sources on hepatic lipid deposition and fatty acid synthesis in the layer's liver. 2. A total of 120 Lohmann Pink commercial layers were divided into three groups of 40 birds each and restricted-fed so that they had similar metabolisable energy intakes. Experimental diets were prepared as follows: (1) maize-soybean meal basal diet (CS) fed at 108 g/d, (2) soybean isolated protein plus lard diet (SL) fed at 63 g/d, (3) soybean isolated protein plus maize starch diet (SC) fed at 94·4 g/d. All feed intakes were limited so that the birds consumed similar quantities of the major nutrient daily; all the birds were fed 4 times/d. 3. Compared with chicks fed on the CS and SC, hepatic EE (ether extraction) and triglyceride of the SL group were increased significantly and the total of cholesterol and phospholipids was increased. However, there were no significant reductions in plasma VLDL and ApoB100 concentrations. 4. The birds fed on the maize starch diets up-regulated srebp-1c and chrebp mRNA transcription levels significantly. The maize starch diet also increased the activity of acetyl CoA carboxylase (ACC) and fatty acid synthase (FAS) significantly. However, the lard diet led to a decrease of ACC activity, but had no significant effect on FAS. 5. These results showed that dietary carbohydrates can induce hepatic lipid deposition by increasing the ACC and FAS activities and up-regulating the srebp-1c and chrebp mRNA transcription levels in the layer's liver much more readily than dietary fat, and layers fed on high carbohydrate diets tend to have more fatty livers.

Effects of dietary dihydropyridine on laying performance and lipid metabolism of broiler breeder hens

The experiment was conducted to investigate the effects of dihydropyridine supplementation on the laying performance and lipid metabolism of broiler breeder hens. A total of 720 forty-five-week old broiler breeder hens were randomly divided into four experimental groups, each group consisting of six replicates of 30 birds. For 10 weeks the birds were fed a maize-soybean meal diet containing 0, 100, 200, 300 mg dihydropyridine/kg, in the respective treatment groups. The daily egg weight and daily feed intake were not affected by dihydropyridine supplementation, but the laying rate and feed efficiency were significantly increased. The percentage of abdominal fat and percentage of liver fat were significantly decreased by dietary dihydropyridine. A level of 100 mg dihydropyridine/kg had no effect on hormone-sensitive triglyceride lipase (HSL) activity in the liver or abdominal fat, though higher levels of dietary dihydropyridine (200 mg/kg or 300 mg/kg) increased HSL activity in the liver and abdominal fat. The concentration of cyclic adenosine monophosphate (cAMP) and superoxide dismutase activity were significantly increased by dihydropyridine, but the malondialdehyde content decreased. The apolipoprotein B concentration was increased at levels of 100 and 200 mg dihydropyridine/kg, but the 300 mg level had no effect on apolipoprotein B, compared with the control group. The triiodothyronine concentration was significantly increased by dietary dihydropyridine. It is concluded that supplementing dihydropyridine in the diet has a beneficial effect on the laying performance and regulates the fat metabolism of broiler breeder hens. The results suggest that the supplementation of 200 mg dihydropyridine/kg diet is the optimal dose for broiler breeder hens.

Effects of phytase B on laying performance, eggshell quality and on phosphorus and calcium balance in laying hens fed phosphorus-deficient maize-soybean meal diets

A study was conducted to evaluate the effects of dietary supplementation of phytase B (product of the Aspergillus niger phyB gene expressed in Trichoderma reesei) on feed intake, laying performance, eggshell quality, and on phosphorus and calcium balance in laying hens. Seventy-two, 40 weeks old Hy Line Brown hens were fed for 14 weeks the following four phosphorus-deficient (0.12% nonphytate phosphorus, NPP), maize-soybean meal-based diets: (1) calcium-deficient (2.8% Ca) control diet; (2) diet 1 + phytase B at the activity of 2.5&amp;nbsp;acid phosphatase units (AcPU/kg); (3) control diet (3.8% Ca); (4) diet 3 + phytase B at the activity of 2.5 AcPU/ kg. Each dietary treatment was fed to 18 cages of hens, 1 hen/cage kept in individual cages. Hens fed the NPP- and Ca-deficient diets consumed more feed (P &amp;lt; 0.01) and excreted less calcium (P &amp;lt; 0.01) than those receiving P-deficient diets with the standard calcium level. There were no effects of calcium level on feed utilization, egg mass, egg weight, and eggshell breaking strength. Egg production, although numerically higher in hens fed low Ca diets with no enzyme added, failed to be significantly different due to the low number of hens investigated and therefore the measurement should be considered as preliminary and supplementary. Phytase B increased mean egg weight by about 7% in layers fed the NPP- and Ca-deficient diet (Ca &amp;times; phytase B interaction, P &amp;lt; 0.05), increased shell breaking strength, particularly at the standard calcium level, significantly enhanced amounts of calcium retained by layers and amounts of&amp;nbsp; phosphorus retained by hens fed the Ca-deficient diets. Additionally, phytase B improved Ca retention at both dietary Ca levels and phosphorus retention in hens fed the Ca-deficient diets. Results of the study indicate that the efficacy of phytase B in NPP-deficient diets is strongly influenced by the dietary calcium level and the enzyme may modulate egg weight, eggshell quality, phosphorus and calcium retention in laying hens fed low-NPP, maize-soybean meal-based diets.

Effect of enzymolytic soybean meal on growth performance, nutrient digestibility and immune function of growing broilers

Enzymolytic soybean meal (ESBM) produced by fermentation and protease hydrolysis contains less trypsin inhibitors and antigen proteins and more soluble protein and small-size peptides than untreated soybean meal (SBM). This study evaluated the effect of ESBM as a partial replacement for SBM on the growth performance, nutrient digestibility and immune function of broilers from 1 to 21 days old. A total of 336 female Cobb chicks at one day old were randomly allocated to 4 treatments with 6 pens per treatment and 14 chicks per pen. Enzymolytic soybean meal replaced SBM at amounts of 50, 100 or 150g/kg in a basal maize-soybean meal diet. Feed intake and body weight were measured weekly. On day 21, six birds per replicate were killed, and ileal digesta and peripheral blood were collected for the measurements of nutrient digestibility and immune function. Results show that there were linear increases (P<0.05) in feed intake, body weight gain, gain:feed and coefficients of ileal apparent digestibility of dry matter, crude protein, energy, Ca and P with increased ESBM feeding. The health status of broilers can also be improved due to the linear increases (P<0.05) in the percentages of T lymphocyte, CD4, CD8, IgA, IgG and IgM in peripheral blood, in response to increased ESBM feeding. The results indicate that ESBM could be a novel soybean protein to improve the nutrition and health of growing broilers.

Nutritional value of peas (Pisum sativum L.) for broilers: apparent metabolisable energy, apparent ileal amino acid digestibility and production performance

Two experiments were conducted to evaluate the nutritional value of four cultivars (Santana, Miami, Courier and Rex) of peas (Pisum sativum L.) for broilers. In Experiment 1, the apparent metabolisable energy (AME) and the apparent ileal amino acid digestibility of these four cultivars were determined. The cultivar effects were found to be not significant (P &gt; 0.05) for the AME and apparent ileal digestibility of amino acids, with the exception of arginine, which was lower (P &lt; 0.05) in Courier than other cultivars. In Experiment 2, using the energy and digestible amino acid values determined in Experiment 1, diets containing 200 g/kg of the four cultivars of peas were formulated and the effects of feeding these diets on the performance and digestive tract development of broiler starters was investigated. Weight gain, feed intake and feed per gain of broiler starters fed diets containing peas were similar (P &gt; 0.05) to those fed the maize-soybean meal diet. In general, the digestive tract development was unaffected (P &gt; 0.05) by the inclusion of peas. The excreta scores of birds fed diets based on Santana, Miami and Rex were similar (P &gt; 0.05) and that of the Courier-based diet was lower (P &lt; 0.05) than those fed the maize-soy control diet. These results suggest that peas are good sources of metabolisable energy and digestible amino acids, and that they can be included at 200 g/kg level as a partial replacement for soybean meal in broiler starter diets without adverse effects on performance.

Effects of dietary dihydropyridine supplementation on growth performance and lipid metabolism of broiler chickens

An experiment was conducted to investigate the effects of dihydropyridine supplementation on growth performance and lipid metabolism of broilers. A total of 480 one-day-old female Arbor Acres broiler chicks were randomly divided into four groups, each group had six replications of 20 birds. Each group was fed a maize-soybean meal diet supplemented with 0, 100, 200, 300 mg/kg dihydropyridine, respectively, for six weeks. At 42 days of age, body weight and feed intake were not affected by dihydropyridine, while feed efficiency was significantly increased by 8.4%, 15.0% and 12.0%, respectively (&lt;I&gt;P &lt;/I&gt;&amp;lt; 0.05). The percentage of abdominal fat and the percentage of liver fat were reduced by 24.5%, 25.9%, 23.3%, and 23.6%, 26.7%, 26.0%, respectively (&lt;I&gt;P &lt;/I&gt;&amp;lt; 0.05). The higher level of dietary dihydropyridine (200 or 300 mg/kg) increased the hormone-sensitive triglyceride lipase activity in liver and abdominal fat (&lt;I&gt;P &lt;/I&gt;&amp;lt; 0.05). The lipoprotein lipase activity in abdominal fat was significantly decreased by dihydropyridine (&lt;I&gt;P &lt;/I&gt;&amp;lt; 0.05). The activity of glucose-6-phosphate dehydrogenase and malic dehydrogenase in liver was significantly reduced, whereas the isocitrate dehydrogenase activity in liver was not affected by dietary dihydropyridine. The content of cAMP was significantly increased by dihydropyridine, but malondialdehyde content was decreased (&lt;I&gt;P &lt;/I&gt;&amp;lt;&amp;nbsp;0.05). Dihydropyridine at doses of 100 and 200 mg/kg increased apolipoprotein B (&lt;I&gt;P &lt;/I&gt;&amp;lt; 0.05), but 300 mg/kg dihydropyridine had no effect on apolipoprotein B compared with the control group. Triiodothyronine was significantly increased by dietary dihydropyridine (&lt;I&gt;P &lt;/I&gt;&amp;lt; 0.05). There were no differences in apolipoprotein A, cholesterol, trigly-cerides, high density lipoprotein-cholesterol, very low density lipoprotein-cholesterol, thyroxine and insulin among dietary treatments. It is concluded that supplementing dihydropyridine has a beneficial effect on feed efficiency and lipid metabolism of broilers, and that 200 mg/kg dihydropyridine supplementation is the optimum dose.

Nutritional value of faba beans ( Vicia faba L.) for broilers: Apparent metabolisable energy, ileal amino acid digestibility and production performance

Two experiments were conducted to evaluate the nutritional value of four cultivars (PGG Tic, Spec Tic, South Tic and Broad) of faba beans ( Vicia faba L.) for broilers. In experiment 1, the apparent metabolisable energy (AME) and ileal amino acid digestibility coefficients of these four cultivars were determined. The cultivar effects were significant (P<0.05) for AME, but ileal amino acid digestibility coefficients were not different (P>0.05) between the four cultivars. The AME value of South Tic cultivar was higher (P<0.05) than those of Spec Tic and Broad cultivars, but similar (P>0.05) to that of PGG Tic. In Experiment 2, using the AME and ileal digestible amino acid values determined in Experiment 1, diets containing 200 g kg −1 of the four cultivars of faba beans were formulated and the effects of feeding these diets on the performance and the digestive tract development of broiler starters were investigated. Weight gain, feed intake and feed per gain of broilers fed faba bean diets were similar (P>0.05) to those fed the maize–soybean meal diet. The performance of birds fed diets containing different cultivars of faba beans was similar (P>0.05). In general, the digestive tract development was unaffected (P>0.05) by the inclusion of faba beans. The exceptions were the relative empty weight and digesta weight of gizzard which were found to be higher (P<0.05) in birds fed diets containing faba beans than those fed the maize–soy diet. Birds fed faba bean diets had better (P<0.05) excreta quality scores than that of the basal diet. These results suggest that faba beans are good sources of energy and amino acids, and that faba beans can be included at 200 g kg −1 inclusion level as a partial replacement for soybean meal in broiler diets without any adverse effects on the performance.

Influence of an enzyme cocktail and phytase individually or in combination in Ven Cobb broiler chickens

1. An experiment (21 d) was conducted to determine if the response of chicks to a cocktail of xylanase, amylase, and protease (XAP) or Escherichia coli-derived phytase individually or in combination when fed a nutritionally marginal maize–soybean meal diet is age-dependent. 2. A total of 250 one-day-old Ven Cobb broiler chicks were allocated to 5 dietary treatments in a randomised complete block design. The treatments were as follows: (1) positive control with supplemental inorganic P; (2) negative control (NC) marginal in P and ME; (3) NC plus XAP to provide (per kg of diet) 650, 1650 and 4000 U of xylanase, amylase, and protease, respectively; (4) NC plus phytase added to provide 1000 phytase units/kg; and (5) NC plus a combination of XAP and phytase. 3. Low ME and P in the NC diet depressed weight gain and gain:feed. A cocktail of XAP alone did not improve performance, but phytase supplementation improved weight gain. The enzymes were additive in their effects on growth performance. 4. The enzymes had no effect on ileal digestible energy. Ileal N digestibility was higher in diets with XAP or phytase individually compared with NC. Both phytase and XAP individually and in combination improved ileal P digestibility compared with NC. 5. Total tract nutrient retention and ME increased as the birds grew older. There were age × diet interactions in total tract retention of P and Ca; improvement in P retention due to phytase use decreased by 50% as the chicks matured. 6. The current study shows that a combination of XAP and phytase improved performance, but the enhancement in performance appears to be due mainly to phytase. Both XAP and phytase were effective in improving P digestibility and retention of chicks receiving nutritionally marginal maize–soybean meal. 7. The data also showed that the chicks benefited more from the enzyme addition at a younger age and that the contribution of the enzymes to nutrient retention decreased with age in chickens.

Effect of Dietary Supplementation of Galacto-mannan- oligosaccharides and Chitosan on Performance and Serum Immune Parameters of 28-day Weaned Piglets Challenged with Pathogenic E.coli

Sun, Z.H., Tang, Z.R., Yin, Y.L., Huang, R.L., Li, T.J., Tang, S.X. and Tan, Z.L. 2009. Effect of dietary supplementation of galacto-mannan-oligosaccharides and chitosan on performance and serum immune parameters of 28-day weaned piglets challenged with pathogenic E. coli. J. Appl. Anim. Res., 36: 207–211. To determine the effects of galacto-mannan-oligosaccharides (GMOS) and chitosan (COS) on growth performance and serum immune parameters 40- 28-d weaned castrated Duroc × Landrace × Yorkshire piglets (8.09 ± 1.87 kg) were challenged with three kinds of pathogenic E. coli (serotype 09, 0141 and 064) and randomly assigned to four treatment groups fed a maize-soybean meal diets containing either no addition (control), 250 mg/kg of lincomycin (LIN), 250 mg/kg of COS (COS) or 2000 mg/kg of GMOS (GMOS), respectively, in α four-week feeding experiment. The feed/gain of control group was poorer than that of other groups with no difference in average daily gain or feed intake. The serum concentrations oflgG, IgA, IgM, IL—6, IL −2 and IL—lβ in experimental groups were higher when compared to control group (P<0.05). The results indicate that GMOS and COS supplemented in weaned piglets diet can improve growth performance and enhance immune function.

An Escherichia coli-derived phytase can fully replace inorganic phosphorus in maize–soybean meal diets for growing-finishing pigs

A total of 396 gilts (PIC 337 × C22 [synthetic white-line dam], 22.4 ± 2.3 kg body weight) was used in a four-treatment trial to investigate the effect of two phytase utilization strategies on growth performance, bone ash and nutrient excretion. Pigs were housed in an environmentally controlled building that contained multiple manure pits. Three contiguous pens housing 11 pigs each were located above each pit. Pens were weighed individually and an average weight for each pit was calculated. Blocks of three pits were then formed based on body weight and randomly allotted to dietary treatments, totaling three pits (nine pens) per treatment. Dietary treatments included (1) a phosphorus (P)-adequate maize–soybean meal control diet (PC), (2) PC less 1.3 g inorganic P (iP)/kg (NC), (3) NC plus 500 FTU phytase (OptiPhos, Phytex LLC)/kg, and (4) a diet devoid of iP with phytase supplemented to meet the P requirements of the pigs. Thus, phytase levels of 1000, 500 and 300 FTU/kg were supplemented from 22 to 49, 49 to 91 and 91 to 130 kg body weight, respectively. The P-releasing values utilized for 300, 500 and 1000 FTU/kg phytase were 1.0, 1.3 and 2.0 g/kg, respectively. Bone ash (metacarpals III and IV; g/100 g and g) was measured on one pig per pen at approximately 74 kg and on three pigs per pen at the end of the trial. Overall, pigs fed the NC diet tended to have lower (P<0.10) weight gains than the other pigs. Additionally, pigs fed the diet devoid of iP with graded phytase supplementation tended to have greater (P<0.10) gain/feed ratios than pigs fed the P-adequate diet. Bone ash (g and g/100 g) was highest (P<0.05) for control and NC + phytase pigs, whereas the NC pigs had the lowest (P<0.05) values, regardless of sampling time. Overall, P excretion was reduced (P<0.01) by 69 g/100 g from pigs fed the diet devoid of iP with graded phytase utilization. Complete replacement of iP with an E. coli-derived phytase maintained growth performance in growing-finishing gilts when diets were formulated to a similar available P concentration using accurate P-releasing efficacy estimates for phytase.

Effect of Galacto-mannan-oligosaccharides or Chitosan Supplementation on Cytoimmunity and Humoral Immunity in Early-weaned Piglets

: Immunomodulatory feed additives might offer alternatives to antimicrobial growth promoters in pig production. This experiment was designed to determine the effects of dietary galacto-mannan-oligosaccharide (GMOS) and chitosan oligosaccharide (COS) supplementation on the immune response in early-weaned piglets. Forty 15-day-old piglets (DurocxLandracexYorkshire) with an average live body weight of 5.6±0.51 kg were weaned and randomly assigned to 4 treatment groups that were fed maize-soybean meal diets containing either basal, 110 mg/kg of lincomycin, 250 mg/kg of COS or 0.2% GMOS, respectively, over a 2-week period. Another six piglets of the same age were sacrificed on the same day at the beginning of the study for sampling, in order to obtain baseline values. Interleukin (IL)-1β gene expression in peripheral blood monocytes, jejunal mucosa and lymph nodes, as well as serum levels of IL-1β, IL-2 and IL-6, IgA, IgG, and IgM, were evaluated for 5 pigs from each group at 15 and 28 days of age. The results indicate that weaning stress resulted in decreases in serum antibody and cytokine levels. Dietary supplementation with GMOS or COS enhanced (p<0.05) IL-1β gene expression in jejunal mucosa and lymph nodes, as well as serum levels of IL-1β, IL-2, IL-6, IgA, IgG and IgM compared to supplementation with lincomycin. These findings suggest that GMOS or COS may enhance the cell-mediated immune response in early-weaned piglets by modulating the production of cytokines and antibodies, which shows that GMOS or COS have different effects than the antibiotic on animal growth and health.

Availability of phytate phosphorus and endogenous phytase activity in the digestive tract of laying hens 20 and 47 weeks old

The availability of phytate phosphorus (P) was determined in 20- and 47-week-old ISA Brown hens fed a maize–soybean meal diet. Phytate P determined by a capillary isotachophoretic method represented 0.358 of the total P of the feed. The availability of phytate P was higher (P<0.001) in 47-week-old (0.53) than in 20-week-old (0.24) hens. The excreta of the older hens contained significantly less phytate P (3.1 mg g DM −1) than that of the younger hens (4.5 mg g DM −1), with the proportion of phytate P in the total faecal P 0.15 and 0.24, respectively. Samples of digesta and intestinal mucosa were diluted with physiological saline containing sodium phytate and incubated anaerobically to determine in vitro phytase activity. Specific activity (per g) in the stomach, intestinal mucosa and caeca was higher (P<0.05) in 47-week-old hens (6.7, 12.1, 143.2 μmol h −1, respectively) than in 20-week-old hens (3.3, 7.0, 103.2 μmol h −1, respectively). A relatively high total phytase activity was found in the caeca of both young (347 μmol h −1) and old (632 μmol h −1) hens compared to that in other digestive segments, with little activity in the stomach (47 and 102 μmol h −1, respectively) and intermediate in the small intestine (226 and 264 μmol h −1, respectively).

Effects of organic zinc and phytase supplementation in a maize–soybean meal diet on the performance and tissue zinc content of broiler chicks

1. The purpose of this study was to investigate the effects of Bioplex Zn® (a chelated zinc proteinate) and phytase supplementation in a maize–soybean meal diet on the performance and tissue zinc (Zn) content of broiler chicks. Treatment structure consisted of a 2 × 6 factorial arrangement with two inclusions of phytase (0 or 500 PU/kg) and 6 of Bioplex Zn® providing 0, 2, 4, 8, 16 and 32 mg Zn/kg diet. A total of 864 chicks were randomly assigned to each of 12 dietary treatments with 6 replicate cages of 12 chicks. 2. Dietary inclusion of phytase increased feed intake, weight gain, plasma Zn content, tibia Zn content, tibia and ash weight. 3. Dietary supplementation of Bioplex Zn® linearly increased feed intake, weight gain, gain to feed ratio, plasma Zn concentration, liver Zn concentration, tibia Zn content, tibia and ash weight. 4. An interactive effect of phytase and Bioplex Zn® on feed intake, weight gain, tibia Zn concentration and tibia ash weight was found. 5. One slope, straight broken-line analysis of weight gain regressed on the supplemental Zn level provided as Bioplex Zn® indicated that 12 mg/kg supplemental Zn without phytase and 7·4 mg/kg supplemental Zn with phytase were required for the optimal weight gain of chicks.

Safety of Improved Milbond-TX ® when fed in broiler diets at greater than recommended levels

A maize-soybean meal diet was supplemented with Improved Milbond-TX ® (IMTX), a hydrated sodium calcium aluminosilicate (HSCAS), in two experiments to determine product safety at elevated levels for broilers fed for 21 days. In Experiment 1, IMTX was incorporated into isonitrogenous and isoenergetic diets at 0, 2.5, 5, 10, 15 and 20 g/kg. In Experiment 2, IMTX was added to the finished feed at 10 or 20 g/kg by weight to simulate a feed mixing error. There was generally a linear (P<0.01) increase in feed intake and body weight of birds given IMTX in Experiment 1 but this trend did not reach significance in Experiment 2. Excreta moisture decreased linearly (P<0.001) in response to increasing IMTX in Experiment 2 but not in Experiment 1. There was no difference (P>0.10) in any blood components due to treatment. Improved Milbond-TX ® appears to be safe for broilers when added at levels up to eight times the recommended amount.