Digestibility of energy and phosphorus in ten samples of distillers dried grains with solubles fed to growing pigs1

A corn-fermented protein ingredient can be included in early nursey diets without compromising pig growth performance and health status

In nursery diets, ingredients with high protein content and highly digestible nutrients, such as corn-fermented protein product with added yeast mass (GDDY), can be included as an alternative to common protein sources. This study investigated the dietary inclusion of GDDY as an alternative protein source on growth performance and intestinal health of weaned pigs. A total of 594 weaned pigs (5.7 ± 0.9 kg; 18.5 days of age) were allotted to 36 pens in a randomized incomplete block design. Pens were assigned to one of 4 dietary treatments: CON: a common nursery feeding program; SBM75: CON diet replacing 75% of soybean meal (SBM) with GDDY; FM/ESBM: CON diet without fish meal (FM) and enzyme-treated SBM (ESBM) + GDDY; GDDY50: CON diet replacing 50% of SBM, FM, and ESBM with GDDY. Experimental diets were formulated to meet nutrient requirements of nursery pigs and provided in meal form through four phases during the nursery period. Pig growth performance was assessed on days 7, 14, 21, 28, 42, and 53. Pen fecal score was assessed daily from days 0 to 14, and 3 times per week from days 15 to 35. Intestinal health was assessed based on plasma immunoglobulin A (IgA) concentration and the differential sugar absorption test. The total tract digestibility of dry matter (DM), crude protein (CP), gross energy (GE), and phosphorus was also evaluated. From days 0 to 7 and days 7 to 14, dietary treatment had no effect (P > 0.05) on BW, ADG, and ADFI. For the rest of the experimental period, ADG and ADFI were greater (P < 0.05) in pigs fed CON in comparison with those fed SBM75 and GDDY50 and did not differ from pigs fed FM/ESBM. Pigs fed GDDY50 tended (P = 0.082) to have greater serum IgA concentration on day 20 when compared with SBM75 and FM/ESBM pigs. There were no differences among dietary treatments for DM, CP, and GE digestibility. Phosphorus digestibility was higher in FM/ESBM (P < 0.05) compared with SBM75 and GDDY50. These results supported the hypothesis that GDDY can be incorporated in nursery pig diets during the first couple weeks after weaning without affecting growth performance. However, in the late nursery period, inclusion levels starting at 14% can compromise performance.

The effect of dietary supplementation with guar (Cyamopsis tetragonoloba) meal protein on the quality and chemical composition of pig carcasses

Recent research efforts have focused on replacing expensive imported genetically modified soybean meal (GM SBM) as a protein source in animal diets with guar meal characterized by similar nutritional characteristics, which could improve meat quality. The aim of this study was to determine the effect of guar meal protein fed to pigs on carcass quality and the content of major nutrients and fatty acids in the longissimus lumborum (LL) muscle. Pigs were divided into four groups. Control group (1) animals were fed diets containing SBM as the main protein source. In diets for experimental groups 2, 3 and 4, SBM protein was replaced with guar meal protein in 25%, 50% and 75%, respectively. It was found that SBM replacement with guar meal protein at 25% affected carcass weight and the lean content, fat content and protein content of the LL muscle. An analysis of linear correlations revealed a strong negative correlation between the concentrations of monounsaturated fatty acids (MUFAs) and saturated fatty acids (SFAs) in the LL muscle of pigs fed diets containing 25% of guar meal protein, which is nutritionally desirable. The results of this study suggest that the dietary inclusion of guar meal protein at up to 25% of SBM protein has no negative effects on the fattening performance of pigs. Meat quality was not affected by diets fortified with guar meal protein.

A strategy of co-fermentation of distillers dried grains with solubles (DDGS) and lignocellulosic feedstocks as swine feed

To meet the sustainable development of the swine feed industry, it is essential to find alternative feed resources and develop new feed processing technologies. Distillers dried grains with solubles (DDGS) is a by-product from the ethanol industry consisting of adequate nutrients for swine and is an excellent choice for the swine farming industry. Here, a strategy of co-fermentation of DDGS and lignocellulosic feedstocks for production of swine feed was discussed. The potential of the DDGS and lignocellulosic feedstocks as feedstock for fermented pig feed and the complementary relationship between them were described. In order to facilitate the swine feed research in co-fermentation of DDGS and lignocellulosic feedstocks, the relevant studies on strain selection, fermentation conditions, targeted metabolism, product nutrition, as well as the growth and health of swine were collected and critically reviewed. This review proposed an approach for the production of easily digestible and highly nutritious swine feed via co-fermentation of DDGS and lignocellulosic feedstocks, which could provide a guide for cleaner swine farming, relieve stress on the increasing demand of high-value swine feed, and finally support the ever-increasing demand of the pork market.

Nutritional values of cottonseed meal from different sources fed to gestating and non-pregnant sows

This study set out to determine the apparent total tract digestibility (ATTD) of the nutrients and energy in six cottonseed meal (CSM) feedstuffs fed to pregnant and non-pregnant sows. The six types of CSM were: two expelled CSMs with crude protein (CP) levels of 40.67% and 44.64%, and four solvent-extracted CSMs with CP levels of 45.18%, 51.16%, 56.44%, and 59.63%. Fourteen gestating sows (at the fourth parity with body weights of 220.6 ± 18.4 kg at days 30 of gestation) and 14 non-pregnant sows (after the third parity with body weights of 219 ± 14.6 kg) were assigned to a replicated 7 × 3 Youden square design with seven diets and three periods. The seven diets included an entirely corn-based diet and six diets each containing 20.0% of the six CSMs tested. Each period included a 5-d acclimation to the experimental diets, followed by a 5-d period during which urine and feces were collected. Significant differences were found among the six CSM diets, regardless of reproductive stage, regarding 1) the ATTD of neutral detergent fiber (NDF) (P < 0.05) and 2) the ATTD of dry matter (DM), organic matter (OM), and CP and the gross energy (GE) (P < 0.01). Non-pregnant sows had a greater ATTD of OM and CP (P < 0.01) compared with gestating sows. The digestible energy (DE) and metabolizable energy (ME) of the six CSM samples ranged from 12.48 to 17.15 MJ/kg and 11.35 to 15.88 MJ/kg, respectively, for non-pregnant sows, and from 12.86 to 16.41 MJ/kg and 12.43 to 14.72 MJ/kg, respectively, for gestating sows. However, the DE, ME, and ME:DE ratios of each CSM were similar between gestating and non-pregnant sows. DE and ME were negatively correlated with NDF and ADF, respectively, but were positively corrected with CP level (P < 0.01). Collectively, the DE, ME, and nutrient digestibility of CSM varied greatly according to the chemical compositions, and CSMs with higher protein and lower fiber levels had greater DE and ME levels.

Short communication: commercial diets for pigs in the United States contain more calcium than formulated

Data from Europe indicate that commercial diets for pigs and poultry contain significantly more Ca than formulated. Therefore, a survey of commercial pig diets used in the United States was conducted to test the hypothesis that the analyzed concentrations of total Ca and total P in commercial pig diets in the United States are not greater than formulated values. A total of 103 diet samples from the commercial swine industry in the United States were collected between 2019 and 2021. Diet samples were provided by feed mills, feed companies, or swine farms located in major swine-producing states in the United States including NC, TN, IA, IN, KS, MN, NE, and IL. Diets were formulated for nursery pigs, growing-finishing pigs, or sows. Each company provided formulated values for total Ca and P in all samples. Samples were sent to the University of Illinois where they were ground and analyzed for Ca and P by inductively coupled plasma-optical emission spectrometry. The formulated values for Ca and P were regressed against analyzed values, and the intercept was considered the estimated under- or over-supply of each mineral. Results indicated that there was an average of 0.19 percentage units more Ca (model; P < 0.001) in the diets than formulated, whereas, for total P, the average oversupply was only 0.06 percentage units (model; P < 0.001). In conclusion, diets used in the U.S. swine industry contain more total Ca than formulated, whereas total P is close to formulated values, which indicates that greater importance is given to P than to Ca in formulation. However, the current data indicate that more attention should be given to the actual concentration of Ca in all Ca-containing feed ingredients to avoid Ca oversupply and its detrimental effect on P digestibility and growth performance of pigs fed diets that do not contain excess P.

Influence of dietary corn distillers' dried grains with solubles on nutrient digestibility, growth performance, and carcass traits in rabbits

Two experiments were performed to evaluate the digestibility and growth performance of New Zealand White rabbits fed corn distillers' dried grains with solubles (DDGS). For the digestibility trial, 20 rabbits were housed in metabolic cages. The animals were distributed in two treatments, T1 (control diet without inclusion of DDGS) and T2 (control diet + 300 g kg^-1 DDGS). For the growth performance trial, 100 rabbits (50 males and 50 females) were assigned in a factorial design 2 × 5 (2 gender × 5 inclusions of DDGS) and five replicates. The treatments were composed of diets with inclusions of 0, 60, 120, 180, and 240 g kg^-1 of DDGS. The rabbits were housed at 35 days old, and the experiment lasted 35 days. The DDGS showed high digestibility for protein (74.10%) and lipids (81.51%) and a high content of digestible energy (2979 kcal kg^-1). In the second trial, growth performance and carcass yield and organ relative weights were evaluated. There were no interactions between gender and DDGS inclusions (P > 0.05). A linear decrease was observed for feed intake (FI) for the period from days 35 to 50 (FI, P = 0.001) and FI and FCR from days 35 to 70 (FI, P = 0.004; FCR, P = 0.001) with the increasing levels of DDGS. Rabbits supplemented with 240 g kg^-1 had lower (P < 0.05) whole carcass yield (WCY) and carcass without head yield compared with the control rabbits. DDGS is highly digestible in rabbits, and when supplemented up to 240 g kg^-1 in diets, it improved FCR but reduced FI and WCY.

Effects of the Partial Substitution of Corn with Wheat or Barley on the Growth Performance, Blood Antioxidant Capacity, Intestinal Health and Fecal Microbial Composition of Growing Pigs

This experiment aimed to investigate the effects of wheat and barley substitution for corn on growth performance, blood antioxidant capacity, intestinal health and fecal microbial composition in growing pigs. Eighteen healthy “Duroc × Landrace × Yorkshire” pigs (50 ± 0.85 kg) were randomly divided into three groups with six replicates and one pig per replicate. The three treatment groups were fed the basal diet (CON) based on corn and soybean meal, respectively, and the experimental group diet was partially replaced by wheat (WH) and barley (BL), respectively. The nutritional levels of the three treatments were the same. The experiment lasted 28 days. Wheat and barley partially replacing corn had no significant effects on growing pigs’ growth performance, blood antioxidant capacity and nutrient digestibility (p > 0.05). Compared with CON and BL, WH significantly increased the duodenal villus height and villus height/crypt depth ratio of growing pigs (p < 0.05). Compared with CON, WH and BL significantly increased the contents of butyric acid, propionic acid and total volatile fatty acid (VFA) in the cecum and colonic digesta of growing pigs (p < 0.05). In addition, the abundance of Turicibacter, Escherichia-Shigella and other harmful bacteria in barley and wheat diet groups were significantly decreased at the genus level (p < 0.05). The abundance of Bifidobacterium, Lactobacillus, Prevotella and Roseburia increased significantly (p < 0.05). In conclusion, barley and wheat partially replacing corn as energy feedstuffs does not affect the growth performance of pigs but can regulate intestinal flora and promote intestinal health.

Digestibility of phosphorus in growing pigs as influenced by source and concentration of dietary phosphorus and collection site

The current study examined the influence of source and concentration of dietary phosphorus (P) on the apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of P in growing pigs. Eighteen cannulated barrows (25 ± 5 kg) were allotted to a triplicate 6 × 3 incomplete Latin square design with six diets and three periods. The diets comprised of soybean meal (SBM) or distillers' dried grain with solubles (DDGS) as sole sources of dietary P, and three concentrations of P (2.0, 2.5 or 3.0 g/kg) in a 2 × 3 factorial arrangement. The AID and ATTD of P were not different (p = 0.37) in all diets. Apparent digestibility of P was affected (p < 0.01) by source and concentration of P. There was no interaction between source and concentration of dietary P on the apparent digestibility of P. Determined by regression analysis, the true ileal digestibility of P was 58.3% or 57.6%, and true total tract digestibility of P was 56.0% or 62.6%, for SBM or DDGS, respectively. The regression-derived ileal endogenous P loss (EPL) was 0.61 or 0.13 g/kg DM intake, and total tract EPL was 0.53 or 0.35 g/kg DM intake, for SBM or DDGS, respectively. In conclusion, the study demonstrated that both the source and concentration of dietary P affect the digestibility of P in growing pigs.

Effects of Using Corn Dried Distillers' Grains with Solubles (cDDGS) as a Partial Replacement for Soybean Meal on the Outcomes of Pig Fattening, Pork Slaughter Value and Quality

Simple Summary

Soybean meal is the principal component of the diets for fattener pigs; however, there is a constant need for alternative, inexpensive, preferably non-GMO (genetic modified organisms) protein sources in swine nutrition. Corn dried distillers’ grains with solubles (cDDGS), by-products of ethanol and bioethanol production, are one such alternative. Due to their chemical composition, they cannot completely replace soybean meal; however, even relatively small additions of cDDGS may decrease the cost of feeding and increase profitability of pig production. In this study, the pigs were fed two different diets: control (cereal–soybean meal-based) or cDDGS (with soybean meal partially replaced with cDGGS). The growth performance as well as carcass and meat quality traits of fatteners fed cDGGS-containing diets did not differ from those of their respective controls. However, the addition of even 15% of cDDGS did result in lower production costs and increased the profitability of pig fattening.

Abstract

The present study set out to determine the effects of incorporating cDDGS into starter, grower, and finisher diets (containing 5%, 10%, and 15% of cDDGS, respectively) on growth performance, carcass and meat quality, and cost effectiveness of pig fattening. Sixty-four pigs (mean body weight of 15.0 ± 2.1 kg) were divided into two groups (n = 32) and fed a control diet (cereal–soybean meal-based) or cDGGS-containing diets (with soybean meal partially replaced with cDDGS). Live weights of pigs as well as weight gains/daily weight gains across all fattening phases did not differ between the two groups of fattener pigs studied (p > 0.05). Addition of cDDGS decreased feed intake per pig during the grower (p < 0.05) and finisher (p < 0.01) phases, and, as a result, throughout the entire fattening period (254 vs. 245 kg for control and cDDGS groups, respectively; p < 0.01). The feed conversion ratio (FCR) for the entire fattening period was significantly less for cDDGS-fed fatteners (2.77) than for controls (2.91; p < 0.05). Carcass weights, fat thickness, and meatiness did not vary between the two groups of animals (p > 0.05). Loin depth was greater in the cDDGS group by ~5 mm (p < 0.05). Slaughter value was higher for the cDDGS group (76.1% vs. 77.0%, p < 0.05). The total cost of fattening and total cost of 1 kg of body weight decreased in cDDGS compared with the control subset of fatteners by ~7% and 8% during the grower and finisher phases, respectively (p < 0.01). The simplified direct surplus per pig was approximately 63% higher for the cDDGS group. Our results indicate that even moderate inclusion of cDDGS to concentrate mixtures (or a partial replacement of soybean meal with cDDGS) may improve FCR without any substantial changes in meat and back fat characteristics as well as significantly decrease the cost of feeding and increase the profitability of pig production.

A review on the use of dried distiller’s grains with solubles (DDGS) in aquaculture feeds

Distiller’s dried grains with soluble (DDGS) to replace fishmeal (FM) or other plant protein sources and its effects on an aquatic animal’s growth performance and health system is rarely discussed. In recent times FM use in aquafeed has been a problem for the aquaculture industry because of the depletion of fish resources in the ocean and the high cost of FM. For that reason, researchers are focusing on reducing the cost of aquafeed production by lowering the inclusion of FM in aquafeed. One of the low-cost alternative protein sources to replace FM is DDGS. The present review discusses the compilation of available literature review and other works on the use of DDGS to replace FM in aquafeed and how it improves the growth performance, immune health system, and disease resistance in an aquatic animal. It focuses on the production of DDGS, the nutritional composition of DDGS, the chemical and physical characteristics of DDGS, and the effects of the DDGS inclusion in aquafeed on the aquatic animal. Apart from improving the growth performance of the aquatic animal when included in aquafeed, it also helps improve the immune health system of the animal. It also helps boost the immune system of the aquatic animal to fight diseases and increase disease resistance when included in aquafeed. Furthermore, DDGS also contains some constituents like carotenoids that help improve the meat quality of the animal when included in aquafeed. The current review also discusses the management and use of technology to improve the aquaculture industry, educate farmers on reducing diseases during the culturing periods, and increase productivity and profit in a friendly environment.

Prediction equations for digestible and metabolizable energy concentrations in feed ingredients and diets for pigs based on chemical composition

OBJECTIVE

The objectives were to develop prediction equations for digestible energy (DE) and metabolizable energy (ME) of feed ingredients and diets for pigs based on chemical composition and to evaluate the accuracy of the equations using in vivo data.

METHODS

A total of 734 data points from 81 experiments were employed to develop prediction equations for DE and ME in feed ingredients and diets. The CORR procedure of SAS was used to determine correlation coefficients between chemical components and energy concentrations and the REG procedure was used to generate prediction equations. Developed equations were tested for the accuracy according to the regression analysis using in vivo data.

RESULTS

The DE and ME in feed ingredients and diets were most negatively correlated with acid detergent fiber or neutral detergent fiber (NDF; r = -0.46 to r = -0.67; p<0.05). Three prediction equations for feed ingredients reflected in vivo data well as follows: DE = 728+0.76×gross energy (GE)-25.18×NDF (R2 = 0.64); ME = 965+0.66×GE-24.62×NDF (R2 = 0.60); ME = 1,133+0.65×GE-29.05×ash-23.17×NDF (R2 = 0.67).

CONCLUSION

In conclusion, the equations suggested in the current study would predict energy concentration in feed ingredients and diets.

Biochemical and Haematological Blood Parameters of Sows and Piglets Fed a Diet with a Dried Fermented Rapeseed Meal

Animal health and welfare can be assessed using biochemical and haematological markers of the blood. The values of these parameters depend in part on the quantity and quality of feed ingredients, i.e. feed protein and feed additives. The aim of the study was to determine the effect of including fermented rapeseed meal (FRSM) in dry feeding system on haematological and biochemical blood parameters of sows and piglets. The experimental material comprised 30 primiparous gilts and 30 multiparous sows after their second lactation. They were randomly divided into two groups of equal size – control and experimental. The animals in control groups CG (15 gilts) and CS (15 sows) received a standard diet for pregnant or lactating sows, depending on the reproductive period. Experimental groups EG and ES were 15 gilts and 15 multiparous sows, respectively, receiving feed with a 4% share of FRSM in place of soybean meal up to 100 d of gestation. In addition, from 100 d of gestation to 7 d of lactation, the sows in these groups received feed with a 9% share of FRSM, and then again a diet with a 4% share of FRSM until the end of lactation. Blood samples were taken from 6 animals from each group in two periods: at 100 days of pregnancy (late pregnancy) and at 27 days of lactation (late lactation). Blood from piglets was taken at 27 days of age (before weaning), from two piglets from each sow (one gilt and one barrow), taking into account the average body weight in the litter. Haematological parameters: Ht, Hb and RBC were determined in whole blood. The plasma content of minerals, activity of selected enzymes and biochemical parameters of sows, gilts and piglets were determined. The diet containing fermented rapeseed meal, fed to pregnant and lactating sows, increased the level of Ht and Hb and RBC content and mineral content (phosphorus, calcium and iron) in the plasma. This effect was mainly observed in primiparous sows. The inclusion of FRSM in the diet of sows reduced the plasma content of total cholesterol and triacylglycerols in sows and piglets, as well as liver enzyme activity, particularly AST in piglets. The use of fermented rapeseed meal in sow diet resulted in better use of mineral compounds, improvement of production effects and health parameters of sow and piglet blood.

Phosphorus flow analysis in the maize based food-feed-energy systems in China

Phosphorus (P) is an essential and limiting nutrient for agricultural systems, where the demand for agricultural products such as food, feed, and bio-fuel are the major drivers of the intensification of agricultural production systems. Globally, maize is one of three main cereal crops, a main feedstock for animal production and a substrate for the production of bio-ethanol. This study investigated P flows through the multiple utilization systems of maize (as represented by the subsystems of food, feed and energy production) at a crop level of 2016 as reference year and made future predictions of P flows for the year 2030 based on different scenarios for food-feed-energy systems in China. For 2016, the subsystem of animal production resulted in the highest waste of P due to inappropriate manure management, but the subsystem of value-added products (Bio-fuel production, distillers dried grains with solubles (DDGS), maize-oil) showed the lowest P use efficiency (39%). From the value-added subsystem, 17% of P from the process flow to the subsystem of animal production as DDGS, and 61% of P is wasted associated with wastewater and sludge. Future scenarios of structural adjustments in the maize consumption system predict that the supply of maize for animal feed will be threatened if the policy of the Biofuel National Promotion before 2020 is fully implemented in China, as current maize production will not meet the future demand of food, feed and energy simultaneously. The results emphasized the use of P waste resources and better sludge management from a systems perspective. This also implied the importance of exploring coordinated development and integrated strategies for sustainable P flow management in multiple utilization systems.

In growing pigs, nutritive value and nutrient digestibility of distillers' by-products obtained from two varieties of rice

In South-East Asia, rice distillers' by-product (RDP) is a widely abundant feedstuff whose adequate incorporation into pig diets is still questionable. Especially, effects of RDP on nutrient digestibility of growing pigs fed corn-soybean meal-based diet are lacking. The objective of this study was to determine nutrient digestibility and energy value of ordinary (ORDP) and glutinous (GRDP) rice distillers' by-product in growing pigs. Two groups of 12 castrated crossbred barrows (Duroc × Landrace × Yorkshire), about 3 months old, 38 ± 1.04-kg initial body weight, were each allocated to a 15-day experiment in which pigs were divided into three isonitrogenous diet-groups. The animals were housed individually in metabolism cages for separated collection of feces and urine. Each diet-group was provided either a control corn-soybean meal diet or a diet in which corn and soybean meal were partly replaced by ORDP or GRDP at 15 or 30% on diet dry matter basis. Glutinous by-product especially showed higher levels in crude protein, neutral/acid detergent fiber, total branched-chain amino acids, and butyric acid. When compared to the control diet, ORDP tented to increase DM intake (P = 0.054) but decreased energy (P < 0.001) and crude protein (P < 0.04) digestibility, while GRDP decreased DM intake (P < 0.001). Both GRDP and ORDP products negatively affected digestibility of ether extract. The average digestible and metabolizable energy of ORDP and GRDP were 17.0 and 16.6, and 17.7, and 17.1 MJ/kg DM, respectively. In conclusion, these results show that both RDP, and especially GRDP, are highly valuable protein and energy sources for pig production.

Effects of distillers dried grains with solubles on amino acid digestibility, growth performance, and carcass characteristics of growing pigs

Two experiments were conducted to compare the standardized ileal digestibility (SID) of AA by growing pigs in European distillers dried grains with solubles (DDGS) produced from wheat, maize, or wheat–maize mixtures and to test the effect of increasing the inclusion levels of wheat DDGS on growth performance of growing-finishing pigs fed diets balanced for NE and SID Lys. In Exp. 1, 12 barrows (initial BW: 23.0 ± 2.2 kg) were surgically equipped with a T-cannula in the distal ileum and randomly allotted to a replicated 6 × 6 Latin square design with six diets and six periods. Five sources of European DDGS were used: wheat DDGS from 2011, wheat DDGS from 2012, wheat-80 DDGS (80% wheat and 20% maize), wheat-70 DDGS (70% wheat and 30% maize), and maize DDGS. Each diet contained one source of DDGS as the sole source of AA and an N-free diet was used to determine basal endogenous losses of AA. Results indicated that the SID of CP was greater (P < 0.05) in maize DDGS compared with wheat DDGS from 2011, wheat DDGS from 2012, and wheat-70 DDGS. The SID of all indispensable AA except Trp was also greater (P < 0.05) in maize DDGS compared with all other DDGS sources used in this experiment. For Trp, the SID in wheat-80 DDGS, wheat DDGS from 2011, and wheat DDGS from 2012 were not different from maize DDGS, but were greater (P < 0.05) than in wheat-70 DDGS. The SID for all indispensable AA except Ile and Trp in wheat-70 DDGS were not different from the values calculated for wheat DDGS from 2011 and wheat DDGS from 2012, and no differences between SID values for AA in wheat DDGS from 2011 and wheat DDGS from 2012 were observed. In Exp. 2, 36 growing pigs (initial BW: 38.3 ± 1.97 kg) were randomly allotted to one of four dietary treatments (one pig/pen and nine replicate pigs/treatment) in a 2-phase feeding program (35 to 65, and 35 to 105 kg BW). The four dietary treatments included diets containing 0%, 10%, 20%, or 30% wheat DDGS. Results indicated that there was no effect of wheat DDGS on pig growth performance or carcass quality. However, addition of wheat DDGS increased linearly (P < 0.015) the indole concentration in the carcasses of the pigs. In conclusion, the SID of AA in maize DDGS produced in Europe is greater than in European wheat DDGS and DDGS produced from mixtures of wheat and maize, but inclusion of 30% wheat DDGS in diets fed to growing-finishing pigs did not affect growth performance or carcass quality.

Determination and prediction of the digestible and metabolizable energy contents of corn germ meal in growing pigs

OBJECTIVE

This experiment was conducted to determine the chemical composition, digestible energy (DE) and metabolizable energy (ME) contents of corn germ meals (CGM) and to develop equations to predict the corresponding energy contents based on the chemical characteristics of individual CGM.

METHODS

Sixty-six barrows (initial body weight = 51.3±4.6 kg) were allotted to 11 diets including a basal diet and 10 CGM test diets in a completely randomized design. In the test diets, CGM was included in replacement of 30% of the energy-providing ingredients in the basal diet, resulting in a final inclusion rate of 29.1%. Each diet was fed to 6 barrows housed in individual metabolism crates for a 7-d acclimation period followed by a 5-d total but separate collection of feces and urine.

RESULTS

Considerable variation was observed in acid-hydrolyzed ether extract, ether extract, ash, calcium (Ca) and total phosphorus contents among the CGM samples. On dry matter (DM) basis, the DE and ME contents of the CGM ranged from 10.22 to 15.83 MJ/kg and from 9.94 to 15.43 MJ/kg, respectively. The acid detergent fiber (ADF) contents were negatively correlated with the DE and ME contents of CGM samples. The best-fit prediction equations for the DE and ME values (MJ/kg DM) of the 10 CGM were: DE = 26.85-0.28 insoluble dietary fiber (%)-17.79 Ca (%); ME = 21.05-0.43 ADF (%)-11.40 Ca (%).

CONCLUSION

The chemical compositions of CGM vary depending on sources, particularly in ether extract and Ca. The DE and ME values of CGM can be predicted based on their chemical composition in growing pigs.

Effects of Bacillus amyloliquefaciens and Bacillus subtilis on ileal digestibility of AA and total tract digestibility of CP and gross energy in diets fed to growing pigs

The objective of this experiment was to test the hypothesis that the apparent ileal digestibility (AID) of AA, CP, and GE, the apparent total tract digestibility (ATTD) of CP and GE, and the apparent hindgut digestibility of CP and GE by growing pigs may be improved by supplementing diets with two direct-fed microbials (DFM) containing different Bacillus strains. Twenty-four growing barrows (initial BW: 22.69 ± 1.48 kg) that had a T-cannula installed in the distal ileum were individually housed and randomly allotted to a three diet, three period design with 24 pigs and three 21-d periods. There were eight pigs per diet in each period for a total of 24 observations per diet. Three diets that were based on corn, soybean meal, and distillers dried grains with solubles were formulated. The control diet contained no DFM, but two additional diets contained two different Bacillus strains (Bacillus amyloliquefaciens or Bacillus subtilis). Feed was provided in mash form in two daily meals at 0800 and 1600 hours. The initial 12 d of each period was the adaptation period to the diet. Fecal and urine samples were collected from days 13 to 18, and ileal digesta were collected for 8 h on days 20 and 21. Results indicated that there were no differences among diets in ATTD of CP, but the AID of CP was reduced (P < 0.05) for the B. subtilis diet compared with control and B. amyloliquefaciens diets. Therefore, the apparent hindgut digestibility of CP was greater (P < 0.005) in pigs fed the B. subtilis diet compared with the other diets. The AID of total indispensable, total dispensable, and total AA was greater (P < 0.05) in the B. amyloliquefaciens diet compared with the control diet. There were no differences among diets in ATTD of GE, but the AID of GE was greater for the B. amyloliquefaciens diet than for the control and the B. subtilis diets (P < 0.001). Therefore, the apparent hindgut digestibility of GE was less (P < 0.05) in the B. amyloliquefaciens diet compared with the other diets. The DE (DM basis) for the B. subtilis diet was greater (P < 0.05) compared with the control and the B. amyloliquefaciens diets. In conclusion, supplementation of Bacillus spp. to diets fed to growing pigs may increase the AID of AA and GE, but there appears to be differences among strains of Bacillus spp. in their impact on AA and energy digestibility.

High-protein distillers dried grains with solubles produced using a novel front-end-back-end fractionation technology has greater nutritional value than conventional distillers dried grains with solubles when fed to growing pigs

Two experiments were conducted to determine the standardized ileal digestibility (SID) of CP and AA, apparent total tract digestibility (ATTD) of GE, and DE and ME in conventional distillers dried grains with solubles (DDGS-CV) and in a novel source of high-protein distillers dried grains with solubles (DDGS-HP) produced by Lincolnway Energy (Nevada, IA). In Exp. 1, 18 barrows (initial BW: 72.47 ± 9.16 kg) that had a T-cannula installed in the distal ileum were allotted to a completely randomized design with 3 diets and 6 replicate pigs per diet. A nitrogen-free diet and 2 diets that contained cornstarch and DDGS-CV or DDGS-HPLincolnway as the sole source of CP and AA were formulated. Diets were fed to pigs for 7 d, and ileal digesta were collected on days 6 and 7 of each period. The SID for Leu, Lys, Met, Phe, and Glu was greater (P < 0.05) in DDGS-HPLincolnway than in DDGS-CV, and the SID of Ile, Val, and total indispensable AA, as well as the SID of Tyr, tended to be greater (P < 0.10) in DDGS-HPLincolnway than in DDGS-CV. No difference between DDGS-CV and DDGS-HPLincolnway was observed for the SID of CP and all other AA. In Exp. 2, 24 barrows (initial BW: 52.80 ± 2.55 kg) were housed individually in metabolism crates and randomly allotted to 1 of 3 diets. A corn-based basal diet (97.25% corn) and 2 diets that contained corn and DDGS-CV or corn and DDGS-HPLincolnway were formulated. Each diet was fed to 8 pigs. Feces and urine were collected using the marker to marker approach with 7-d adaptation and 5-d collection periods. The DE and ME in DDGS-CV and DDGS-HPLincolnway were calculated using the difference procedure. The DE and ME in DDGS-HPLincolnway on an as-fed basis were greater (P < 0.05) than in corn and DDGS-CV, but the ATTD of GE in DDGS-HPLincolnway and DDGS-CV was less (P < 0.01) than in corn. In conclusion, the SID of some AA and the DE and ME in DDGS-HPLincolnway were greater than in DDGS-CV.

Effects of physicochemical characteristics of feed ingredients on the apparent total tract digestibility of energy, DM, and nutrients by growing pigs

Effects of physicochemical characteristics of feed ingredients on DE and ME and apparent total tract digestibility (ATTD) of GE, DM, and nutrients were determined in growing pigs using ingredients with different ratios between insoluble dietary fiber (IDF) and soluble dietary fiber (SDF). Eighty growing barrows (BW: 48.41 ± 1.50 kg) were allotted to a randomized complete block design with 10 diets and eight replicate pigs per diet. Dietary treatments included a corn-based diet, a wheat-based diet, a corn-soybean meal (SBM) diet, and seven diets based on a mixture of the corn-SBM diet and canola meal, distillers dried grains with solubles (DDGS), corn germ meal (CGM), copra expellers, sugar beet pulp (SBP), synthetic cellulose, or pectin. Values for the ATTD of DM and nutrients were also compared with the in vitro digestibility of GE, DM, and nutrients. Results indicated that the ATTD of GE was greater (P < 0.05) in wheat than in canola meal, DDGS, CGM, copra expellers, SBP, and synthetic cellulose, but not different from corn, SBM, or pectin. SBM had greater (P < 0.05) DE and ME (DM basis) compared with all other ingredients. The concentration of ME (DM basis) was greater (P < 0.05) in wheat than in canola meal, DDGS, CGM, copra expellers, SBP, synthetic cellulose, and pectin, but not different from corn. Stronger correlations between total dietary fiber (TDF) and DE and ME than between ADF or NDF and DE and ME were observed, indicating that TDF can be used to more accurately predict DE and ME than values for NDF or ADF. The DE, ME, and the ATTD of DM in ingredients were positively correlated (P < 0.05) with in vitro ATTD of DM, indicating that the in vitro procedure may be used to estimate DE and ME in feed ingredients. Swelling and water-binding capacity were positively correlated (P < 0.05) with the ATTD of IDF, TDF, nonstarch polysaccharides (NSP), and insoluble NSP, and viscosity was positively correlated (P < 0.05) with the ATTD of NDF, IDF, and insoluble NSP, indicating that some physical characteristics may influence digestibility of fiber. However, physical characteristics of feed ingredients were not correlated with the concentration of DE and ME, which indicates that these parameters do not influence in vivo energy digestibility in feed ingredients. It is concluded that the DE and ME in feed ingredients may be predicted from some chemical constituents and from in vitro digestibility of DM, but not from physical characteristics.

Analysis for low-molecular-weight carbohydrates is needed to account for all energy-contributing nutrients in some feed ingredients, but physical characteristics do not predict in vitro digestibility of dry matter

An experiment was conducted to quantify nutrient and fiber fractions of feed ingredients and to determine in vitro apparent ileal digestibility (IVAID) and in vitro apparent total tract digestibility (IVATTD) of DM and OM in each ingredient. Ten ingredients that vary in fiber concentration and composition were used: corn, wheat, soybean meal (SBM), canola meal, distillers dried grains with solubles (DDGS), corn germ meal, copra expellers, sugar beet pulp (SBP), synthetic cellulose (SF), and pectin. Correlations between chemical and physical characteristics of ingredients and IVAID and IVATTD of DM and OM were determined. The physical characteristics measured included bulk density, water-binding capacity (WBC), swelling, and viscosity. The analyzed GE was compared with values for GE calculated from all energy-contributing components. Results indicated that the analyzed chemical composition of most ingredients added to 100% or greater, except for DDGS, SBP, and SF, where nutrients added to only 94.29%, 88.90%, and 96.09%, respectively. The difference between the sum of the calculated GE of the analyzed components and the analyzed GE of the ingredients ranged from -2.25 MJ/kg in DDGS to 1.74 MJ/kg in pectin. No correlation was observed between swelling, WBC, or viscosity and IVAID or IVATTD of DM or OM. The concentration of insoluble dietary fiber (IDF) and total dietary fiber (TDF) was negatively correlated (P < 0.05) with IVAID and IVATTD of DM and OM. There was a tendency for NDF (r = -0.60) and ADF (r = -0.61) to be negatively correlated (P < 0.10) with IVAID of DM. However, no correlation was observed between the concentration of CP, GE, acid-hydrolyzed ether extract, lignin, or soluble dietary fiber and IVAID and IVATTD of DM and OM. The stronger correlations between IDF, TDF, and insoluble non-starch polysaccharides and IVAID and IVATTD of DM and OM than between ADF and NDF and IVAID and IVATTD of DM and OM indicate that the concentration of TDF in feed ingredients is a better predictor of the digestibility of DM and OM than values for NDF and ADF. In conclusion, the calculated GE of some feed ingredients was in agreement with the analyzed GE, which gives confidence that energy-contributing components were accounted for, but for DDGS and SBP, it was not possible to account for all analyzed GE. Concentrations of IDF and TDF, but not the physical characteristics of feed ingredients, may be used to estimate IVAID and IVATTD of DM and OM in feed ingredients.

Effects of withdrawing high-fiber ingredients before marketing on finishing pig growth performance, carcass characteristics, and intestinal weights

Two experiments were conducted to determine the duration of high-fiber ingredient removal from finishing pig diets before marketing to restore carcass yield and carcass fat iodine value (IV), similar to pigs continuously fed a corn-soybean meal diet. In experiment 1, 288 pigs (initially 38.4 ± 0.3 kg body weight [BW]) were used in an 88-d study and fed either a low-fiber corn-soybean meal diet from day 0 to 88 or a high-fiber diet containing 30% corn distillers dried grains with solubles and 19% wheat middlings until day 20, 15, 10, 5, or 0 before slaughter and switched to the low-fiber corn-soybean meal diet thereafter. Diets were not balanced for net energy. From day 0 to 88, pigs continuously fed the high-fiber diet tended to have increased average daily feed intake (P = 0.072) and decreased G:F and carcass yield (P = 0.001) compared with pigs fed the low-fiber corn-soybean meal diet. Pigs continuously fed the high-fiber diet had greater (P < 0.010) IV of jowl, backfat, belly, and ham collar fat than those fed the low-fiber corn-soybean meal diet throughout. As days of withdrawal increased, pigs previously fed the high-fiber diet had increased carcass yield (quadratic; P = 0.039). Pigs continuously fed the high-fiber diet had heavier (percentage of hot carcass weight [HCW]) full large intestines (P = 0.003) than pigs fed the corn-soybean meal diet. Full large intestine weight decreased (linear; P = 0.018) as withdrawal time increased. Belly fat IV tended (linear; P = 0.080) to improve as withdrawal time increased. In experiment 2, a total of 1,089 pigs (initially 44.5 ± 0.1 kg BW) were used in a 96-d study with the same dietary treatments as in experiment 1, except pigs were fed the high-fiber diet until day 24, 19, 14, 9, or 0 before slaughter and then switched to the corn-soybean meal diet. Pigs fed the high-fiber diet throughout had decreased average daily gain and G:F (P = 0.001) compared with those fed the low-fiber corn-soybean meal diet. For pigs initially fed the high-fiber diet and then switched to the low-fiber corn-soybean meal diet, G:F tended to improve (linear; P = 0.070) as withdrawal period increased. Pigs fed the high-fiber diet throughout had decreased HCW (P = 0.001) compared with those fed the low-fiber corn-soybean meal diet and HCW marginally increased (quadratic; P = 0.077) as withdrawal period increased. In summary, switching pigs from a high-fiber diet to a corn-soybean meal diet for up to 24 d before market increased carcass yield (experiment 1) or HCW (experiment 2) with the improvement most prominent during the first 5 to 9 d after withdrawal.

Effects of wheat supplementation levels on growth performance, blood profiles, nutrient digestibility, and pork quality in growing-finishing pigs

OBJECTIVE

This study was conducted to evaluate various wheat supplementation levels on growth performance, blood profiles, nutrient digestibility, and pork quality in growing-finishing pigs.

METHODS

A total of 120 growing pigs ([Yorkshire×Landrace]×Duroc), with an average 27.75± 1.319 kg body weight, were used in growth trial. Pigs were allotted into each treatment by body weight and sex in 4 replicates with 6 pigs per pen in a randomized complete block design. Four-phase feeding programs were used in this experiment. The treatments included the following: i) corn-soybean meal (SBM) - based diet (CON), ii) corn-SBM - based diet+15% of wheat (W15), iii) corn-SBM - based diet+30% of wheat (W30), iv) corn-SBM - based diet+45% of wheat (W45), and 5) corn-SBM-based diet+60% of wheat (W60).

RESULTS

There was no significant difference in growth performance among the dietary treatments. However, the gain-to-feed (G:F) ratio tended to increase (quadratic, p<0.08) when the pigs were fed a higher wheat diet during the finishing period. The digestibility of crude ash and fat tended to decrease as the wheat supplementation level increased (p<0.08). The proximate analysis of the longissimus muscle was not affected by the dietary level of wheat. The crude ash content in pork was decreased linearly as the wheat supplementation level increased (p = 0.05). There was no significant difference in the pH level, shear force, water holding capacity, and cooking loss of the pork. In pork and fat, L*, a*, and b* values were not significantly different among dietary treatments.

CONCLUSION

Wheat can be supplemented up to 60% in a growing-finishing pig without detrimental effects on growth and pork quality. The G:F ratio tended to improve in the finishing period by wheat inclusion.

Evaluation of collection method and diet effects on apparent digestibility and energy values of swine diets

Two experiments were conducted to investigate the effects of collection method and diet type on digestibility coefficients. In Exp. 1, 24 barrows were fed either a corn-soybean meal (CSBM) diet or CSBM with 20% dried distillers' grains with solubles (CSBM-DDGS). In Exp. 2, the effects of basal diet and collection method on determination of dried distillers' grains with solubles (DDGS) digestibility were studied using 24 barrows. The 4 diets used in Exp. 2 were: a CSBM (basal 1) , a barley-canola meal (BCM; basal 2), 80% basal 1 with 20% DDGS (CSBM-DDGS), and 80% basal 2 with 20% DDGS (BCM-DDGS). In both experiments, feces were collected using a time-based collection method (DY) or a "marker-to-marker" collection method (MM). Diets contained 0.5% of titanium dioxide (TiO) for estimating digestibility using the index marker approach (IM). The apparent total tract digestibility (ATTD) of DM and GE were lower ( < 0.05) in the CSBM-DDGS diet than in the CSBM diet in Exp. 1 but were not different in Exp. 2. All the estimates of BCM-based diets were consistently lower ( < 0.05) than those of CSBM-based diets. In Exp. 1, digestibility coefficients determined by the DY and MM were not different from each other, whereas those estimates were lower ( < 0.05) using the IM than those using the total collection approach (TC; DY and MM). In Exp. 2, interactions ( < 0.05) were observed between diet type and method for dietary digestibility coefficients. Digestibility and energy values estimated by the DY and MM were not different in pigs fed CSBM-based diets and the BCM-DDGS diet, whereas those estimates were greater ( < 0.05) using the DY than those using the MM in pigs fed the BCM. There were no interactions between basal diet and method for estimating DDGS digestibility. The ATTD of DM and GE of DDGS using the MM were greater ( < 0.05) than those using the IM, and ATTD of N tended to be greater ( < 0.10) using the MM than that using the IM. All estimates using the DY were not different from those using the MM or the IM, except that DE of DDGS was greater ( < 0.05) using the DY than when using the IM. Digestibility estimates of DDGS were not affected by basal diets. The mean DE and ME (as-fed basis) of DDGS were 3,994 and 3,688 kcal/kg, respectively, when estimated using the basal 1 diet and were 3,919 and 3,547 kcal/kg, respectively, when estimated using the basal 2 diet. In conclusion, both collection methods can be used to estimate energy and nutrient digestibility of diets and DDGS when using CSBM-based diets.

Effects of production area and microbial phytase on the apparent and standardized total tract digestibility of phosphorus in soybean meal fed to growing pigs

An experiment was conducted to determine if the area in which soybeans are grown influences the concentration of P, phytate, and macro- and microminerals in the soybean meal (SBM) produced from the beans and, therefore, also influences the apparent total tract digestibility (ATTD) and the standardized total tract digestibility (STTD) of P in SBM. The second objective was to test the hypothesis that inclusion of microbial phytase will increase the ATTD and STTD of P in SBM regardless of where the beans were grown. Twenty sources of SBM were procured from crushing facilities located in different regions of the United States that were separated into 3 zones: 1) the northern growing area (Michigan, Minnesota, and South Dakota), 2) the eastern growing area (Georgia, Illinois, Indiana, and Ohio), and 3) the western growing area (Iowa, Missouri, and Nebraska). For each source of SBM, 2 diets based on cornstarch and SBM were formulated; one of these diets contained no microbial phytase and the other diet contained 500 units/kg of microbial phytase. Two hundred growing barrows (16.90 ± 1.79 kg initial BW) were individually placed in metabolism crates and allotted to a randomized complete block design with 40 diets and 5 replicate pigs per treatment. Feces were collected for 4 d after a 4-d adaptation period using the marker-to-marker procedure. Results indicated that there were no differences in concentration of Ca, P, phytate, and macro- and microminerals among SBM from the different zones. However, there was a tendency ( = 0.055) for an increase in concentration of nonphytate P in SBM from the western growing area (0.25%) compared with SBM from the northern growing area (0.23%) and the eastern growing area (0.23%). There were no differences in feed intake, absorbed P, ATTD of P, STTD of P, Ca intake, Ca output, or ATTD of Ca for pigs fed SBM from the 3 zones. However, there was a tendency (P = 0.066) for an increase in P intake and P output from pigs fed SBM from the western growing area compared with pigs fed SBM from the northern growing area. There was an increase ( < 0.05) in absorbed P, ATTD and STTD of P, and ATTD of Ca if microbial phytase was included in the diets, but the quantity of P and Ca that was excreted in the feces decreased ( < 0.001) if microbial phytase was used. Overall, no differences in ATTD and STTD of P exist among SBM produced in different areas of the United States, but microbial phytase will increase the digestibility of P in SBM.

Amino acid, phosphorus, and energy digestibility of Aspergillus niger fermented rapeseed meal fed to growing pigs

Fermented rapeseed meal (FRSM) contains greater levels of protein and less glucosinolates, NDF, and phytic acid than rapeseed meal (RSM) and might be an attractive feedstuff for swine, but its nutritional value has been poorly characterized. The aim of this study was to evaluate the nutritional value of RSM fermented by for growing pigs. In Exp. 1, 6 barrows (21.20 ± 1.47 kg initial BW) fitted with a T-cannula in the distal ileum were allotted to a repeated 3 × 3 Latin square with 3 diets and 3 periods per square to determine the apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of CP and AA. A N-free diet and 2 diets containing RSM or FRSM as the only source of AA were formulated. Results indicated that there was no difference in AID and SID of CP and most AA between FRSM and RSM. However, the AID of 2 indispensable AA (Lys and Met) and 3 dispensable AA (Asp, Gly, and Tyr) were greater (P < 0.05) for FRSM than for RSM. The SID of only 2 dispensable AA (Gly and Tyr) were greater (P < 0.05) for FRSM than for RSM. In Exp. 2, 16 barrows (32.57 ± 2.67 kg initial BW) were allotted to 2 diets formulated to contain RSM or FRSM as the sole source of P to determine the apparent total tract digestibility (ATTD) of P. The ATTD and standardized total tract digestibility (STTD) of P in FRSM were 72.10 and 77.31%, respectively. These values were greater (P < 0.01) than in RSM (34.79 and 41.34%, respectively). In Exp. 3, 24 growing barrows (32.23 ± 1.33 kg initial BW) were fed 3 diets with 8 replicate pigs per diet to measure concentration of DE and ME of FRSM. A corn diet consisting of 98.40% corn was formulated and 2 additional diets were formulated by mixing corn with 35% RSM or FRSM. The DE and ME in FRSM (2,887 and 2,650 kcal/kg of DM, respectively) were greater (P < 0.05) than those in RSM (2,609 and 2,328 kcal/kg of DM, respectively). In summary, solid-state fermentation of RSM by has a greater nutritional value than RSM and is a promising alternative high-quality protein source.

Determination of the energy value of corn distillers dried grains with solubles containing different oil levels when fed to growing pigs

This experiment used indirect calorimetry to determine the net energy (NE) content of five corn distillers dried grains with solubles (corn DDGS) containing different oil levels and to compare the NE obtained using indirect calorimetry with that calculated using previously published prediction equations. There were two samples of high-oil DDGS, one sample of medium-oil DDGS and two samples of low-oil DDGS. Twelve barrows (initial BW of 32.8 ± 2.0 kg) were used in a repeated 3 × 6 Youden square design with three periods and six diets. The diets were comprised of a corn-soybean meal basal diet and five diets containing 29.25% of one of the corn DDGS added at the expense of corn and soybean meal. During each period, the pigs were individually housed in metabolism crates for 16 days which included 7 days for adaption to feed and environmental conditions. On day 8, the pigs were transferred to respiration chambers and fed one of the six diets at 2300 kJ ME/kg BW^0.6 /day. Faeces and urine were collected from day 9 to 13 and heat production (HP) was also measured. From day 14 to 15, the pigs were fed 893 kJ ME/kg BW^0.6 /day to allow them to adapt from the fed to the fasted state. On the last day of each period (day 16), the pigs were fasted and fasting HP was measured. The digestible energy value was 16.0, 17.1 and 15.3 MJ/kg DM, the metabolizable energy value was 14.6, 15.5 and 13.7 MJ/kg DM and the NE value was 10.7, 11.0 and 9.4 MJ/kg DM, for the high-oil, medium-oil and low-oil corn DDGS, respectively. The NE obtained with indirect calorimetry in the present study did not differ from values calculated using previously published prediction equations.

Use of feed technology to improve the nutritional value of feed ingredients

Two experiments were conducted to test the hypothesis that reduced particle size of corn will improve the caloric utilisation of corn fed to weanling pigs and to determine effects of pelleting, extrusion and extrusion and pelleting on energy and nutrient digestibility in diets containing low, medium or high levels of fibre. In Experiment 1, 128 pigs were used (initial bodyweight (BW) of 9.41 ± 1.54 kg). Pigs were randomly allotted to four diets in a randomised complete block design. There were four pigs per pen and eight replicate pens per treatment. The corn used was ground to different particle sizes (i.e. 865, 677, 485 or 339 µm). In Experiment 2, three diets were formulated, including a low-fibre diet, a medium-fibre diet-, and a high-fibre diet. Each diet was divided into four batches after mixing and either fed in a meal form without further processing or pelleted, extruded, or extruded and pelleted. In total, 24 growing pigs (initial BW: 26.5 ± 1.5 kg) with a T-cannula installed in the distal ileum were allotted to the diets in a split-plot design, with eight pigs allotted to each level of fibre. Ileal digesta and faecal samples were collected and the apparent ileal digestibility of energy, crude protein and dry matter were calculated as was the metabolisable energy in each diet. Results of Experiment 1 indicated that final BW and average daily gain were not affected by corn particle size. However, average daily feed intake decreased (linear, P < 0.05) as mean particle size decreased from 865 to 677, 485 and 339 µm. Likewise, gain to feed ratio increased (linear, P < 0.05) from 0.65 to 0.66, 0.70 and 0.69 for pigs fed diets containing corn ground to a mean particle size of 865, 677, 485 and 339 µm, respectively. In Experiment 2, results indicated that pelleting, extrusion, or pelleting and extrusion improved (P < 0.05) the apparent ileal digestibility of energy and dry matter, but in most cases, there were no differences among the pelleted, the extruded, and the extruded and pelleted diets. Medium- and high-fibre diets that were extruded had greater metabolisable energy (P < 0.05) than the meal diets. In conclusion, results indicated that gain to feed of pigs fed diets containing corn with the smaller particle size was increased compared with diets containing corn with a greater particle size. In addition, energy utilisation may be improved by pelleting or extrusion or by a combination of the two technologies, but the response seems to be greater for extrusion in diets that are relatively high in fibre.

The consequences of introducing stochasticity in nutrient utilisation models: the case of phosphorus utilisation by pigs

Simulation models of nutrient utilisation ignore that variation in pig system components can influence the predicted mean and variance of the performance of a group of pigs. The objective of this study was to develop a methodology to investigate how variation in feed composition would (a) affect the outputs of a nutrient utilisation model and (b) interact with variation that arises from the traits of individual pigs. We used a P intake and utilisation model to address these characteristics. Introduction of stochasticity gave rise to a number of methodological challenges--for example, how to generate variation in both feed composition and pigs and account for correlations between ingredients when modelling variation associated with feed mixing efficiency. Introducing variation in feed composition and pig phenotype resulted in moderate decreases in mean digested, retained and excreted P predicted for a population of pigs and an increase in their associated CV. A lower percentage of pigs in the population were predicted to meet their requirements during the feeding period considered, by comparison with the no-variation scenario. Variation in feed ingredient composition contributed more to performance variation than variation due to mixing efficiency. When variations in both feed composition and pig traits were considered, it was the former rather than the latter that had the dominant influence on variability in pig performance. The developed framework emphasises the consequences of random variability on the predictions of nutrient utilisation models. Such consequences will have a significant impact on decisions about management strategies such as feeding that are subject to variation.

Effects of Aspergillus niger fermented rapeseed meal on nutrient digestibility, growth performance and serum parameters in growing pigs

The aim of the present study was to investigate the influences of Aspergillus niger fermented rapeseed meal (FRSM) on growth performance and nutrient digestibility of growing pigs. A total of 72 growing pigs (body weight = 40.8 ± 2.1 kg) were used in feeding trials, lasting for up to 42 days, and were randomly allotted to one of three diets, including a corn-soybean meal control diet as well as two experimental diets containing 10% unfermented rapeseed meal (RSM) or 10% FRSM. The results showed that average daily gain and feed conversion ratio of pigs fed FRSM were superior (P < 0.05) to that of pigs fed unfermented RSM and did not differ from the control. Pigs fed control diet had higher (P < 0.05) total tract apparent digestibility for dry matter, protein, calcium and phosphorus than pigs fed unfermented RSM diet and did not differ from the FRSM diet. Pigs fed FRSM had lower levels (P < 0.05) of serum aspartate transaminase compared to unfermented RSM. In conclusion, solid state fermentation using Aspergillus niger may improve the growth performance and nutrient digestibility of RSM for pigs and FRSM is a promising alternative protein for pig production.

Determination and prediction of energy values in corn distillers dried grains with solubles sources with varying oil content for growing pigs

This study was conducted to determine the DE and ME content of 25 samples of corn distillers dried grains with solubles (DDGS) fed to growing pigs and to generate prediction equations for DE and ME based on chemical analysis. The 25 samples included 15 full-oil (no oil extracted; ether extract [EE] > 8%) DDGS and 10 reduced-oil (oil extracted; EE < 8%) DDGS collected from 17 ethanol plants in China. A corn–soybean meal diet constituted the basal diet and the other 25 diets replaced a portion of the corn, soybean meal, and lysine of the basal diet with 28.8% of 1 of the 25 corn DDGS sources. Seventy-eight barrows (initial BW = 42.6 ± 6.2 kg) were used in the experiment conducted over 2 consecutive periods (n = 6 per treatment) using a completely randomized design. For each period, pigs were placed in metabolism cages for a 5-d total collection of feces and urine following a 7-d adaptation to the diets. Among the 25 corn DDGS samples, EE, NDF, DE, and ME content (DM basis) ranged from 2.8 to 14.2%, 31.0 to 46.6%, 3,255 to 4,103 kcal/kg, and 2,955 to 3,899 kcal/kg, respectively. Using a stepwise regression analysis, a series of DE and ME prediction equations were developed not only among all 25 DDGS but also only within 15 full-oil DDGS and 10 reduced-oil DDGS samples. The best fit equations of DE (kcal/kg DM) for the complete set of 25 DDGS, 15 full-oil DDGS, and 10 reduced-oil DDGS were 2,064 – (38.51 × % NDF) + (0.64 × % GE) – (39.70 × % ash), –(87.53 × % ADF) + (1.02 × % GE) – (22.99 × % hemicellulose), and 3,491 – (40.25 × % NDF) + (46.95 × % CP), respectively. The best fit equations for ME (kcal/kg DM) for the complete set of 25 DDGS, 15 full-oil DDGS, and 10 reduced-oil DDGS were 1,554 – (44.11 × % NDF) + (0.77 × % GE) – (68.51 × % ash), 7,898 – (42.08 × % NDF) – (136.17 × % ash) + (101.19 × % EE) (103.83 × % CP), and 4,066 – (46.30 × % NDF) + (45.80 × % CP) – (106.19 × % ash), respectively. Using the sum of squared residuals to compare the accuracy of the 3 groups of prediction equations revealed that separate equations for full-oil DDGS and reduced-oil DDGS each provided a better fit than a single equation for the entire set of DDGS sources. These results indicated that the DE and ME values in corn DDGS are related to the chemical composition, primarily the EE and fiber concentrations. Specific prediction equations derived from full-oil and reduced-oil DDGS are better than equations derived from the entire set of DDGS.

Empiric narrowing of the net energy value of reduced-oil corn distillers’ dried grain with solubles for growing-finishing pigs

Smit, M. N., Zamora, V., Young, M. G., Campbell, N., Uttaro, B. and Beltranena, E. 2015. Empiric narrowing of the net energy value of reduced-oil corn distillers’ dried grain with solubles for growing-finishing pigs. Can. J. Anim. Sci. 95: 225–241. This study attempted to empirically narrow down the net energy (NE) value of reduced-oil corn distillers’ dried grains and solubles (RO-cDDGS) by evaluating the response in pig growth performance, live backfat and loin depth, carcass traits, and primal pork cuts tissue composition to feeding diets formulated increasing the assumed NE value of RO-cDDGS, expecting a brisk change in slope of the response at the point at which the NE value of RO-cDDGS would be identified. In total, 1056 cross-bred pigs (31.7 kg) housed in 48 pens by gender were fed dietary regimens including 30% RO-cDDGS (6.7% ether extract) with assumed NE values of 1.7, 1.85, 2.0, 2.15, 2.3, or 2.45 Mcal kg−1over five growth periods (Grower 1: days 0–21, Grower 2: days 22–42, Grower 3: days 43–63, Finisher 1: days 64–76, Finisher 2: day 77 to market weight). Pig body weights were measured and feed disappearance (ADFI) was calculated by pen on days 0, 21, 42, 63, 76 and weekly thereafter until target slaughter weight (120 kg). For the entire trial (days 0–76), increasing the assumed NE value of RO-cDDGS linearly increased (P<0.01) ADFI and total lysine intake, did not affect NE intake and daily weight gain (ADG), quadratically decreased (P<0.05) feed efficiency, linearly decreased (P<0.05) live backfat depth and backfat:loin depth ratio, and did not affect carcass characteristics or pork primal cut tissue composition. Segmented regression only identified a change in slope for carcass ADG and lean ADG at 1.85 Mcal kg−1. These results indicate that the experimental approach taken was not reliable in narrowing down the NE value of RO-cDDGS because the decrease in dietary NE was too small (0.03 Mcal kg−1d), which limited the change in dietary Lys:NE ratio with increasing assumed NE value of RO-cDDGS. The approach resulted in progressive, but small changes in slope rather than a clearly identifiable point where one could conclude that the incremental dietary energy contribution from RO-cDDGS changed the response in a given variable.

Review: Dietary fiber utilization and its effects on physiological functions and gut health of swine

Although dietary fiber (DF) negatively affects energy and nutrient digestibility, there is growing interest for the inclusion of its fermentable fraction in pig diets due to their functional properties and potential health benefits beyond supplying energy to the animals. This paper reviews some of the relevant information available on the role of different types of DF on digestion of nutrients in different sections of the gut, the fermentation process and its influence on gut environment, especially production and utilization of metabolites, microbial community and gut health of swine. Focus has been given on DF from feed ingredients (grains and coproducts) commonly used in pig diets. Some information on the role DF in purified form in comparison with DF in whole matrix of feed ingredients is also presented. First, composition and fractions of DF in different feed ingredients are briefly reviewed. Then, roles of different fractions of DF on digestion characteristics and physiological functions in the gastrointestinal tract (GIT) are presented. Specific roles of different fractions of DF on fermentation characteristics and their effects on production and utilization of metabolites in the GIT have been discussed. In addition, roles of DF fermentation on metabolic activity and microbial community in the intestine and their effects on intestinal health are reviewed and discussed. Evidence presented in this review indicates that there is wide variation in the composition and content of DF among feed ingredients, thereby their physico-chemical properties in the GIT of swine. These variations, in turn, affect the digestion and fermentation characteristics in the GIT of swine. Digestibility of DF from different feed ingredients is more variable and lower than that of other nutrients like starch, sugars, fat and CP. Soluble fractions of DF are fermented faster, produce higher amounts of volatile fatty acid than insoluble fractions, and favors growth of beneficial microbiota. Thus, selective inclusion of DF in diets can be used as a nutritional strategy to optimize the intestinal health of pigs, despite its lower digestibility and consequential negative effect on digestibility of other nutrients.

Ferulic acid dehydrodimer and dehydrotrimer profiles of distiller's dried grains with solubles from different cereal species

Ferulic acid dehydrodimers (DFA) and dehydrotrimers (TriFA) ester-linked to plant cell wall polymers may cross-link not only cell wall polysaccharides but also other cell wall components including proteins and lignin, thus enhancing the rigidity and potentially affecting the enzymatic degradation of the plant cell wall. Corn, wheat, and mixed-cereal distiller's dried grains with solubles (DDGS) were investigated for composition of DFAs and TriFAs by reversed phase high-performance liquid chromatography with ultraviolet detection. Corn DDGS contained 5.3 and 5.9 times higher contents of total DFAs than wheat and mixed-cereal DDGS, respectively. Furthermore, the contents of total TriFAs were 5.7 and 6.3 times higher in corn DDGS than in wheat and mixed-cereal DDGS, respectively. In addition, both corn grains and corresponding DDGS had similar profiles of individual DFAs and TriFAs, indicating that ferulic acid cross-links in the corn cell wall are presumably not modified during fermentation and DDGS processing.