Dietary supplementation of valine, isoleucine, and tryptophan may overcome the negative effects of excess leucine in diets for weanling pigs containing corn fermented protein.

BACKGROUND: Diets with high inclusion of corn co-products such as corn fermented protein (CFP) may contain excess Leu, which has a negative impact on feed intake and growth performance of pigs due to increased catabolism of Val and Ile and reduced availability of Trp in the brain for serotonin synthesis. However, we hypothesized that the negative effect of using CFP in diets for weanling pigs may be overcome if diets are fortified with crystalline sources of Val, Trp, and (or) Ile. METHODS: Three hundred and twenty weanling pigs were randomly allotted to one of 10 dietary treatments in a completely randomized design, with 4 pigs per pen and 8 replicate pens per treatment. A corn-soybean meal diet and 2 basal diets based on corn and 10% CFP or corn and 20% CFP were formulated. Seven additional diets were formulated by fortifying the basal diet with 20% CFP with Ile, Trp, Val, Ile and Val, Ile and Trp, Trp and Val, or Ile, Trp and Val. A two-phase feeding program was used, with d 1 to 14 being phase 1 and d 15 to 28 being phase 2. Fecal scores were recorded every other day. Blood samples were collected on d 14 and 28 from one pig per pen. On d 14, fecal samples were collected from one pig per pen in 3 of the 10 treatments to determine volatile fatty acids, ammonium concentration, and microbial protein. These pigs were also euthanized and ileal tissue was collected. RESULTS: There were no effects of dietary treatments on any of the parameters evaluated in phase 1. Inclusion of 10% or 20% CFP in diets reduced (P < 0.05) final body weight on d 28, and average daily gain (ADG) and average daily feed intake (ADFI) in phase 2 and for the entire experimental period. However, pigs fed the CFP diet supplemented with Val, Ile, and Trp had final body weight, ADFI, ADG and gain to feed ratio in phase 2 and for the entire experiment that was not different from pigs fed the control diet. Fecal scores in phase 2 were reduced (P < 0.05) if CFP was used. CONCLUSIONS: Corn fermented protein may be included by up to 20% in diets for weanling pigs without affecting growth performance, gut health, or hindgut fermentation, if diets are fortified with extra Val, Trp, and Ile. Inclusion of CFP also improved fecal consistency of pigs.

Addition of Spray-Dried Plasma in Phase 2 Diets for Weanling Pigs Improves Growth Performance, Reduces Diarrhea Incidence, and Decreases Mucosal Pro-Inflammatory Cytokines.

The hypothesis that pigs fed a low crude protein (CP) diet with 6% spray-dried plasma (SDP) in phase 1 will have improved growth and intestinal health if the phase-2 diet contains 2.5% SDP was tested. Three hundred weaned pigs were used. Growth performance, feces, blood, and intestinal tissue were evaluated. Pigs fed 6% SDP in phase 1 had improved average daily gain (ADG) and final body weight (BW), but had reduced villus-height-to-crypt-depth ratio in phase 2 if 2.5% SDP was included in the normal-CP diet (p < 0.05), but not in the low-CP diet. Diarrhea incidence was less (p < 0.05) with 2.5% SDP in the phase 2 diet and for the low-CP diet. Ileal mucosa interleukin-1α (IL-1α) and IL-1ß decreased (p < 0.05) for pigs fed the phase-1 diet with 6% SDP compared with pigs fed the diet without SDP. Addition of 2.5% SDP in phase 2 reduced (p < 0.05) IL-1ß compared with the diet without SDP. Although the combination of SDP and low CP did not affect intestinal health in phase 2, diarrhea incidence and pro-inflammatory cytokines were reduced in pigs fed SDP in phase 1 or phase 2 or if a low-CP diet was fed.

Reduction of particle size of field peas (Pisum sativum L.) increases net energy and digestibility of starch when fed to growing pigs, but there is no difference in nutritional value between peas from the U.S. and peas from Canada.

Two experiments were conducted to test the hypothesis that particle size of field peas and location where peas are grown do not affect apparent total tract digestibility (ATTD) of nutrients and gross energy (GE), digestible energy (DE), metabolizable energy (ME), and net energy (NE), apparent ileal digestibility (AID) of starch, or standardized ileal digestibility (SID) of crude protein (CP) and amino acids (AA). In both experiments, three sources of field peas were used. One source was obtained from the U.S., and two sources were obtained from Canada (i.e., Canada 1, Canada 2). The U.S. field peas were ground to 678, 457, or 265 µm, whereas the two sources of Canadian peas were ground to 411 and 415 µm. Therefore, five batches of field peas were used in both experiments. A basal diet contained corn and soybean meal as the only source of energy, starch, and AA, and five diets containing corn and soybean meal and 50% of each source of field peas were also formulated. The ratio between corn and soybean meal was 1.92:1 in all diets. In Exp. 1, an N-free diet was also used to calculate basal endogenous losses of AA and CP, but in Exp. 2, no N-free diet was used. In Exp. 1, seven barrows (initial body weight = 60.6 ± 2.1 kg) that had a T-cannula installed in the distal ileum were allotted to a 7 × 7 Latin square design with seven diets and seven periods. In Exp. 2, twenty-four pigs (initial body weight = 30.8 ± 1.0 kg) were housed in six calorimeter chambers with four pigs per chamber. The six chambers were allotted to one of the six diets using a 6 × 6 Latin square design with six consecutive periods of 15 d. Results of Exp. 1 demonstrated that the SID of CP and AA was not influenced by the origin of the peas or by the particle size, but the AID of starch increased (linear, P < 0.001) as particle size was reduced from 678 µm to 457 or 265 µm. Results of Exp. 2 indicated that growing location did not affect concentrations of DE, ME, or NE of field peas, but concentrations of DE, ME, and NE increased (linear, P < 0.05) when the particle size was reduced from 678 µm to 457 or 265 µm. In conclusion, field peas grown in Canada or the U.S. have the same nutritional value, but starch digestibility and NE increase if the particle size of field peas is reduced.

The pig is an excellent model to determine amino acid digestibility of human foods and to generate data needed to meet human amino acid requirements.

The protein value of any food item is determined by the quantity and ileal digestibility of indispensable amino acids in that food. To determine the ileal digestibility of amino acids, an animal model needs to be used, and the pig is the preferred model because values for ileal digestibility obtained in pigs are representative of values obtained in humans. In addition, pigs are omnivorous animals like humans, they are meal eaters, they consume most diets that humans consume, they are easy to work with, and they can be used for repeated determinations of digestibility in many foods. It is, therefore, possible to use pigs to establish a database with digestibility values for human foods and by correcting digestibility values obtained in pigs for the basal endogenous losses of amino acids, it is possible to calculate true ileal digestibility values that are additive in mixed meals. As a consequence, the protein quality of a meal consisting of several food items can be calculated based on digestibility values obtained in pigs. Future work needs to focus on expanding existing databases for amino acid digestibility in foods to include more food items, which will make it possible to estimate the amino acid value of more mixed meals. It is also necessary that the amino acid values in mixed meals be related to requirements for digestible indispensable amino acids in the individuals consuming the meals. The current contribution describes the basic steps in determining amino acid digestibility in human foods using the pig as a model and also outlines future steps needed to further improve amino acid nutrition in humans.

Pelleting and particle size reduction of corn increase net energy and digestibility of fiber, protein, and fat in corn-soybean meal diets fed to group-housed pigs.

BACKGROUND: Reduction of the particle size of corn increases energy digestibility and concentrations of digestible and metabolizable energy. Pelleting may also reduce particle size of grain, but it is not known if there are interactions between particle size reduction and pelleting. The objective of this experiment was to test the hypothesis that particle size reduction and pelleting, separately or in combination, increase N balance, apparent total tract digestibility (ATTD) of fiber and fat, and net energy (NE) in corn-soybean meal diets fed to group-housed pigs. METHODS: Six corn-soybean meal-based diets were used in a 3 × 2 factorial design with 3 particle sizes of corn (i.e., 700, 500, or 300 µm) and 2 diet forms (i.e., meal or pelleted). Pigs were allowed ad libitum access to feed and water. Twenty-four castrated male pigs (initial weight: 29.52 kg; standard diviation: 1.40) were allotted to the 6 diets using a 6 × 6 Latin square design with 6 calorimeter chambers (i.e., 4 pigs/chamber) and 6 periods. Oxygen consumption and CO2 and CH4 productions were measured during fed and fasting states and fecal and urine samples were collected. RESULTS: Regardless of particle size of corn, the ATTD of gross energy (GE), N, and acid-hydrolyzed ether extract (AEE), and the concentration of NE were greater (P < 0.05) in pelleted diets than in meal diets. Regardless of diet form, the ATTD of GE, N, and AEE, and the concentration of NE were increased (linear; P < 0.05) by reducing the particle size of corn, but the increase was greater in meal diets than in pelleted diets (interaction; P < 0.05). CONCLUSIONS: Both pelleting and reduction of corn particle size increased nutrient digestibility and NE, but increases were greater in meal diets than in pelleted diets.

Influence of particle size and origin of field peas on apparent ileal digestibility of starch and amino acids and standardized ileal digestibility of amino acids when fed to growing pigs.

The objective was to test the hypothesis that particle size and origin of field peas influence the apparent ileal digestibility (AID) of starch, crude protein (CP), and amino acids (AA) and the standardized ileal digestibility (SID) of AA. Three sources of field peas were procured. One source was from the United States and two sources were from Canada. The U.S. source and one of the sources from Canada (i.e., Canada 1) were each divided into two batches and ground to achieve a target particle size of 250 or 450 µm, whereas the other source from Canada (i.e., Canada 2) was only ground to a target particle size of 250 µm. Each batch of field peas was included in one diet as the only source of AA. An N-free diet was used to determine the basal endogenous losses of CP and AA. Six barrows (initial weight: 50.5 kg; SD = 3.7) that had a T-cannula installed in the distal ileum were randomly allotted to a 6 × 6 Latin square design with six diets and six 7-d periods. Ileal digesta from pigs were collected for 2 d after 5 d of adaptation. Data were analyzed using a statistical model that included batch of field peas as the fixed effect and animal and period as the random effects. Contrast statements were used to analyze the effects of particle size, origin, and the interaction between particle size and origin. Results indicated that the AID of starch was increased by reducing the particle size in the U.S. source of field peas, but that was not the case for the Canada 1 source (interaction; P < 0.001). Particle size did not influence the AID of CP or AA, but the Canada 2 source of field peas had greater (P < 0.05) AID of Trp, Ala, Cys, Gly, and Tyr than the field peas from the United States. The SID of CP and AA was also not affected by the particle size of field peas. The SID of CP and Trp was greater (P < 0.05), and the SID of His, Ile, and Thr tended (P < 0.10) to be greater in the Canada 2 source compared with the U.S. source, but no differences between the two Canada sources were observed. In conclusion, a few differences in SID of AA between field peas produced in the United States and peas produced in Canada were observed, but there was no effect on SID of AA of reducing the particle size of field peas from 450 to 250 µm, whereas the AID of starch increased by reducing the particle size only in the field peas from the United States.

Effect of the pelleting process on diet formulations with varying levels of crystalline amino acids and reducing sugars on digestibility in growing pigs.

The objective of this experiment was to determine the effects of pelleting on the standardized ileal digestibility (SID) of amino acids (AA) and crude protein (CP) in diets with or without increased concentrations of free AA and reducing sugars (RS). Eight individually housed, ileal cannulated barrows (initially 31.4 kg) were allotted to an 8 × 8 Latin square with eight diets and eight 7-d periods with ileal digesta collected on days 6 and 7. Treatments were arranged in a 2 × 2 × 2 factorial with the main effects of diet form (mash or pellet), crystalline AA (low or high), or RS (low or high), provided by distillers dried grains with solubles and bakery meal. Diets were pelleted to achieve a hot pellet temperature of 85 to 88 °C. Data were analyzed as a Latin square design using the GLIMMIX procedure of SAS 9.4. A feed form × RS interaction (P < 0.026) for SID of tryptophan was observed. Feeding pelleted low RS diets increased SID of tryptophan compared with mash high and low RS diets, and pelleted high RS diets. For the main effects of feed form, the SID of total AA, CP, and indispensable AA was greater (P < 0.042) in pelleted diets compared with mash diets. For the main effects of crystalline AA, pigs fed high crystalline AA had increased (P = 0.007) SID of tryptophan and decreased (P = 0.050) SID of histidine compared with those fed low crystalline AA diets. For the main effects of RS, high RS diets had decreased (P < 0.05) SID of total AA, CP, and indispensable AA compared with low RS diets. In conclusion, pelleting diets increased AA digestibility, and pelleting diets with increased crystalline AA or RS did not affect the improvement in AA digestibility from pelleting. Diets formulated with high crystalline AA had increased SID of tryptophan. Formulating diets with high RS resulted in decreased AA digestibility compared with corn-soybean meal-based diets.

The objective of this study was to determine the effects of pelleting on the standardized ileal digestibility (SID) of amino acids (AA) in diets with or without increased concentrations of free AA and reducing sugars (RS). Treatments were arranged in a 2 × 2 × 2 factorial with the main effects of diet form (mash or pellet), crystalline AA (low or high), or RS (low or high), provided by dried distillers grains with solubles and bakery meal. A total of 8 illeal cannulated barrows were fed treatments in an 8 × 8 Latin square design. Results indicated that there was no evidence of interactions between diet types and diet form, indicating that increasing amounts of crystalline AA and RS did not reduce amino acid digestibility when pelleting diets. Additionally, pelleting diets resulted in increased amino acid digestibility compared to mash diets. Diets formulated with 20% dried distillers grains with solubles and 15% bakery resulted in decreased amino acid digestibility compared with the corn­soybean meal-based diets. Crystalline amino acid concentration did not influence amino acid digestibility of indispensable AA, except for SID of tryptophan which was increased in diets with higher concentrations of crystalline AA.

Chemical composition of barley and co-products from barley, corn, and wheat produced in South-East Asia or Australia.

OBJECTIVE: A study was conducted to determine the chemical composition of barley and co-products from barley, corn, and wheat produced in South-East Asia or Australia, and to test the hypothesis that production area or production methods can impact the chemical composition of wheat co-products. METHODS: Samples included seven barley grains, two malt barley rootlets, one corn gluten feed, one corn gluten meal, one corn bran, eight wheat brans, one wheat mill mix, and four wheat pollards. All samples were analyzed for dry matter, gross energy, nitrogen, amino acids (AA), acid hydrolyzed ether extract, ash, minerals, starch, and insoluble dietary fiber and soluble dietary fiber. Malt barley rootlets and wheat co-products were also analyzed for sugars. RESULTS: Chemical composition of barley, malt barley rootlets, and corn co-products were in general similar across countries. Wheat pollard had greater (p<0.05) concentrations of tryptophan, magnesium, and potassium compared with wheat bran, whereas wheat bran had greater (p<0.05) concentration of copper than wheat pollard. There were no differences in chemical composition between wheat bran produced in Australia and wheat bran produced in Thailand. CONCLUSION: Intact barley contains more starch, but fewer AA, than grain co-products. There were only few differences in the composition of wheat bran and wheat pollard, indicating that the two ingredients are similar, but with different names. However, corn gluten meal contains more protein and less fiber than corn bran.

Digestibility of energy and concentrations of metabolizable energy and net energy varies among sources of bakery meal when fed to growing pigs.

The null hypothesis that there are no differences in concentrations of digestible energy (DE), metabolizable energy (ME), and net energy (NE) among different sources of bakery meal was tested in a regional experiment involving 5 of the universities on the North Central Coordinating Committee-42 on Swine Nutrition. Eleven sources of bakery meal were procured from the swine producing areas in the United States and included in one diet as the only energy containing ingredient, and each diet was then divided into 5 batches that were used at the University of Illinois, Purdue University, University of Kentucky, University of Nebraska, and North Carolina State University. At each university, diets were fed to 22 growing pigs (2 pigs per diet) that were placed in metabolism crates, and feces and urine were collected for 5 d after a 7-d adaptation period. Diets and collected samples of feces and urine were dried and analyzed for gross energy. The apparent total tract digestibility of dry matter (DM) and gross energy and concentrations of DE, ME, and NE were calculated. Results indicated that there were considerable variation in the nutritional composition among the different sources of bakery meal with relatively large coefficients of variation for crude protein, starch, and acid hydrolyzed ether extract, but it was possible to analyze all sources of bakery meal to account for 100% of the ingredients. The average DE, ME, and NE in the 11 sources of bakery meal was 3,827, 3,678, and 2,799 kcal/kg DM, respectively. However, in contrast to the hypothesis, differences (P < 0.05) among sources of bakery meal in concentrations of DE (3,827 ±â€…201 kcal/kg DM), ME 3,678 ±â€…200 kcal/kg DM), and NE (2,799 ±â€…156 kcal/kg DM) were observed, but the variation among the 11 sources of bakery meal was not greater than what is usually observed among different sources of other ingredients. The differences observed are likely a consequence of the different product streams and production procedures used to produce the bakery meal. In conclusion, the average DE, ME, and NE in 11 sources of bakery meal is close to values previously reported, but there is some variation among sources depending on origin.

An experiment was conducted at 5 universities to determine digestible energy (DE), metabolizable energy (ME), and net energy (NE) by growing pigs in 11 sources of bakery meal that were sourced from swine producing states in the United States. Each source was analyzed and included in a diet as the only source of energy. Diets were fed to growing pigs that were housed in metabolism crates and fecal and urine samples were collected. Values for DE and ME were calculated from analyzed energy in diets, feces, and urine, and NE was calculated using a prediction equation. Results indicated that it was possible to analyze each source of bakery meal to 100%. The average DE, ME, and NE was 3,827, 3,678, and 2,799 kcal/kg dry matter. Although some variability among the 11 sources of bakery meal was observed, the variability in DE and ME values in bakery meal was not greater than what is observed in most other normally used feed ingredients.

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.

Calcium is often oversupplied in pig diets because limestone, the main source of Ca in pig diets, is an inexpensive feed ingredient and is often used as a carrier in premixes or a diluent in feed ingredients. However, excess Ca may be detrimental to P digestibility and pig growth performance. It was recently reported that commercial pig and poultry diets sold in Europe contain significantly more Ca than formulated, but it is not known if the Ca concentrations in commercial pig diets in the United States also contain more Ca than formulated. Therefore, a survey of commercial diets from the United States was conducted to compare analyzed and formulated values for Ca. A total of 103 diets were collected from feed mills, feed companies, or swine integrators in the United States between 2019 and 2021. Samples were analyzed for total Ca and total P. Results from the regression model used to evaluate the data indicated that diets on average contained 0.19 percentage units more total Ca and 0.06 percentage units more total P than expected. Thus, more attention needs to be paid to the inclusion of Ca in pig diets to avoid Ca oversupply and the negative effects of Ca on pig growth performance.

Digestibility of calcium in calcium-containing ingredients and requirements for digestible calcium by growing pigs.

The concentration of Ca in plant feed ingredients is low compared with the requirement for pigs and most Ca in diets for pigs is provided by limestone and Ca phosphate. To determine digestibility values for Ca that are additive in mixed diets, the standardized total tract digestibility (STTD) of Ca needs to be calculated, and the STTD of Ca by growing pigs in most Ca-containing ingredients has been reported. Although Ca is an inexpensive nutrient compared with P and amino acids, excess Ca needs to be avoided because excess dietary Ca results in reduced P digestibility, reduced feed intake, and reduced growth performance of pigs. Recent data indicate that most diets produced for pigs in the United States and Europe contain ~0.20 percentage units more Ca than formulated, which likely is because of the use of limestone as a carrier in feed additives or as a flow agent in other ingredients. An excess of this magnitude without a corresponding excess of P will result in a reduction in daily gain of growing pigs by 50 to 100 g. Greater emphasis, therefore, needs to be placed on determining the concentration of Ca in diets for pigs. Microbial phytase increases the digestibility of both Ca and P and it is, therefore, important that the release of both Ca and P by phytase is considered in diet formulation. However, due to the relationship between Ca and P in postabsorptive metabolism, diets need to be formulated based on a ratio between digestible Ca and digestible P. To maximize average daily gain, this ratio needs to be less than 1.40:1.0 in diets for weanling pigs, and the ratio needs to be reduced as the body weight of pigs increases. In contrast, to maximize bone ash, the digestible Ca to digestible P ratio needs to increase from 1.67:1.0 in 11 to 25 kg pigs to 2.33:1.0 in finishing pigs. Gestating sows have reduced STTD and retention of Ca and P compared with growing pigs and formulation of diets for sows based on digestibility values obtained in growing pigs will result in inaccuracies in the provision of Ca and P. There is, however, a lack of data for the digestibility of Ca and P by gestating and lactating sows, and responses to microbial phytase by sows are not fully understood. There is, therefore, a need for research to generate more data in this area. In the present review, a summary of data for the digestibility of Ca in feed ingredients for pigs and estimates for the requirement for digestible Ca by growing and finishing pigs are provided.

Concentration of Ca in most plant feed ingredients is low compared with the requirement for pigs and dietary Ca is, therefore, mostly provided by limestone and calcium phosphates. Although Ca is an inexpensive nutrient compared with P and amino acids, excess dietary Ca may result in reduced P digestibility, feed intake, and growth performance of pigs. Excretion of P from pigs is increased if dietary Ca is provided above the requirement, which may increase environmental pollution. Therefore, determination of the digestibility of Ca in dietary sources of Ca and formulation of diets based on the ratio between digestible Ca and digestible P are needed to reduce Ca and P excretions. This review provides a summary of values for the digestibility of Ca in feed ingredients and also provides estimates for the requirement for digestible Ca by weanling and growing-finishing pigs. Summarized data from experiments that determined the requirement for digestible Ca demonstrated that there are linear correlations between body weight of growing-finishing pigs and digestible Ca to digestible P ratios needed to maximize growth or bone ash.

Effect of heat treatment on protein quality of rapeseed protein isolate compared with non-heated rapeseed isolate, soy and whey protein isolates, and rice and pea protein concentrates.

BACKGROUND: Rapeseed protein isolate is used in the food industry, and heating is often used during rapeseed processing. However, the digestible indispensable amino acid score (DIAAS) for heat-treated rapeseed protein isolate is unknown. The present study aimed to test the hypothesis that heating rapeseed protein isolate improves protein quality resulting in DIAAS that is greater than for pea and rice protein concentrates, and comparable to that of soy and whey protein isolates. RESULTS: Standardized ileal digestibility (SID) of amino acids (AA), except leucine and methionine, was not different between heat-treated rapeseed protein isolate and soy protein isolate, but SID of most AA was greater (P < 0.001) for heat-treated rapeseed protein isolate than for brown rice protein concentrate, pea protein concentrate, rapeseed protein isolate and soy protein isolate, but not whey protein isolate. Non-heated rapeseed protein isolate had a reduced (P < 0.001) DIAAS for 6-month-old to 3-year-old children compared with soy protein isolate, but this was greater (P < 0.001) than for pea and brown rice protein concentrates. The DIAAS for heat-treated rapeseed protein isolate was greater (P < 0.001) than for non-heated rapeseed protein isolate for all age groups. Heat-treated rapeseed protein isolate and whey protein isolate had a DIAAS > 100 for individuals older than 3 years. CONCLUSION: Rapeseed protein isolate had a DIAAS comparable to soy protein isolate, but heat-treated rapeseed protein isolate and whey protein isolate had DIAAS ≥ 100, qualifying these proteins as 'excellent'. Rice and pea protein concentrates had DIAAS < 75. © 2023 Society of Chemical Industry.

Standardized ileal digestibility of amino acids differs among sources of bakery meal when fed to growing pigs.

A multistate experiment involving universities in IL, IN, KY, and MN was conducted as a part of the research efforts by the North-Central Coordinating Committee-42 on swine nutrition. The null hypothesis that there are no differences in the standardized ileal digestibility (SID) of amino acids (AA) among different sources of bakery meal was tested. Eleven sources of bakery meal were procured from swine-producing states in the United States and each source was included in one diet as the sole source of AA. A N-free diet was prepared as well. Diets were prepared in one batch and divided into four sub-batches that were subsequently distributed to the four participating universities. At each university, diets were fed to 12 pigs that had a T- cannula installed in the distal ileum. Pigs were allotted to incomplete Latin square designs with 12 pigs and 4, 5, or 6 periods for a total of 21 replicate pigs per diet. Each period lasted 7 d with ileal digesta being collected from the cannulas on days 6 and 7. Samples were analyzed for AA and the SID of each AA was calculated. Results indicated that there were differences (P < 0.001) in the SID of all AA except Pro among the 11 sources of bakery meal. The differences in SID of AA observed in this experiment were greater than what is usually observed among sources of the same ingredient, indicating that there is more variability among sources of bakery meal than among different sources of other ingredients. This is likely a consequence of different raw materials being used in the production of different sources of bakery meal. Regardless of source of bakery meal, the AA with the least SID was Lys indicating that some of the raw materials in the product streams used to generate the bakery meals may have been overheated. Additionally, the Lys:crude protein ratio in each source of bakery meal was not a good predictor of the SID of Lys, which likely reflects the different raw materials being included in the different meals. In conclusion, the SID of AA varies among different sources of bakery meal and the SID of Lys is less than the SID of all other indispensable AA.

Eleven sources of bakery meal were used in a regional experiment to determine digestibility of amino acids. Diets containing each source of bakery meal were prepared at one university and distributed to three other universities. Diets were fed to pigs that had a cannula installed in the distal ileum and ileal digesta were collected from pigs for 2 d following 5 d of adaptation. Results indicated that there is considerable variation in the digestibility of all amino acids among sources of bakery meal, which is likely a reflection of differences in raw material use among different producers of bakery meal. Results also demonstrated that the digestibility of Lys is less than the digestibility of all other amino acids, indicating that some of the raw materials used in the production of bakery meal may have been heat damaged. It may, therefore, be necessary to add additional Lys to diets containing bakery meal.

Chemical composition of banana meal and rice bran from Australia or South-East Asia.

OBJECTIVE: A study was conducted to determine the chemical composition of banana meal and rice bran from Australia or South-East Asia and test the hypothesis that there are no differences in rice bran produced in different countries, but there are differences between full-fat and defatted rice bran. METHODS: Two sources of banana meal and 22 sources of rice bran (full-fat or defatted) from Australia or South-East Asia were used. All samples were analyzed for dry matter, gross energy, nitrogen, amino acids (AA), acid hydrolyzed ether extract (AEE), ash, minerals, total starch, insoluble dietary fiber, and soluble dietary fiber. Banana meal was also analyzed for sugars including glucose, fructose, maltose, sucrose, stachyose, and raffinose. RESULTS: Chemical analysis demonstrated that banana meal from the Philippines is primarily composed of starch. Full-fat rice bran from Australia had greater (p<0.05) concentrations of AEE, lysine, and glycine than samples from the Philippines and Vietnam. Full-fat rice bran from Australia and Thailand had greater (p<0.05) concentrations of gross energy and most AA than rice bran from Vietnam. Full-fat rice bran from Australia had greater (p<0.05) concentrations of tryptophan and manganese than all other sources, but full-fat rice bran from the Philippines contained less (p<0.05) zinc than all other sources of rice bran. Gross energy, AEE, and copper were greater (p<0.05) in full-fat rice bran compared with defatted rice bran, but defatted rice bran contained more (p<0.05) crude protein, ash, insoluble dietary fiber, total dietary fiber, AA, and some minerals than full-fat rice bran. CONCLUSION: Banana meal is a high-energy source that can be used as an alternative ingredient in livestock diets. Full-fat rice bran from Australia and Thailand contained more concentrations of AEE and AA than samples from the Philippines or Vietnam. Full-fat rice bran had more gross energy and AEE than defatted rice bran, whereas defatted rice bran contained more crude protein, ash, and total dietary fiber.

Limited impacts of high doses of dietary copper on the gut bacterial metal resistome explain negligible co-selection of antibiotic resistance.

High dietary intake of Cu has previously been linked to the selection of Cu resistance and co-selection of antibiotic resistance in specific gut bacteria. Based on a novel HT-qPCR metal resistance gene chip as combined with 16S rRNA gene amplicon sequencing and phenotypic resistance typing of Escherichia coli isolates, we here report the impacts of two contrasting Cu-based feed additives on the swine gut bacterial metal resistome and community assembly. DNA was extracted from fecal samples (n = 80) collected at day 26 and 116 of the experiment from 200 pigs allotted to five dietary treatments: negative control (NC) diet with 20 µg CuSO4 g-1 and four diets added 125 or 250 µg CuSO4 g-1 feed or 125 or 250 µg Cu2O g-1 feed to the NC diet. Dietary Cu supplementation reduced the relative abundance of Lactobacillus, but it had negligible impacts on bacterial community composition relative to the gut microbiome maturation effect (time). The relative importance of different bacterial community assembly processes was not markedly affected by the dietary Cu treatments, and differences in swine gut metal resistome composition could be explained primarily by differences in bacterial community composition rather than by dietary Cu treatments. High dietary Cu intake (250 µg Cu g-1) selected for phenotypic Cu resistance in E. coli isolates, but surprisingly it did not result in increased prevalence of the Cu resistance genes targeted by the HT-qPCR chip. In conclusion, the lacking impacts of dietary Cu on the gut bacterial metal resistome explain results from a previous study showing that even high therapeutic doses of dietary Cu did not cause co-selection of antibiotic resistance genes and mobile genetic elements known to harbor these genes.

Effects of corn hardness and drying temperature on digestibility of energy and nutrients in diets fed to growing pigs.

Two experiments were conducted to test the hypothesis that corn kernel hardness and drying temperature influence the ileal digestibility of starch and amino acids (AA), as well as apparent total tract digestibility (ATTD) of gross energy (GE) and total dietary fiber (TDF) in diets for growing pigs. Two corn varieties with average or hard endosperm were grown and harvested under similar conditions, and after harvest, each variety was divided into 2 batches that were dried at 35 and 120 °C, respectively. Therefore, four batches of corn were used. In experiment 1, 10 pigs (67.00 ±â€…2.98 kg) with a T-cannula installed in the distal ileum were allotted to a replicated 5 × 5 Latin square design with 5 diets and 5 periods giving 10 replicates per diet. A nitrogen-free diet and four diets containing each source of corn as the only AA source were formulated. Results indicated that neither variety of corn nor drying temperature influenced apparent ileal digestibility of starch in the grain. The standardized ileal digestibility of most AA was less (P < 0.05) in corn dried at 120 °C compared with corn dried at 35 °C resulting in concentrations of most standardized ileal digestible AA being less (P < 0.05) in corn dried at 120 °C than in corn dried at 35 °C. In experiment 2, 40 pigs (20.82 ±â€…1.74 kg) were housed in metabolism crates and allotted to 4 diets with 10 replicate pigs per diet. The four corn-based diets used in experiment 1 were also used in experiment 2. Feces and urine were collected using the marker-to-marker approach with 5-d adaptation and 4-d collection periods. Results indicated that diets containing hard endosperm corn had greater (P < 0.05) ATTD of TDF than diets containing average endosperm corn. The ATTD of GE in hard endosperm corn was also greater (P < 0.05), and concentrations of digestible energy and metabolizable energy in hard endosperm corn were greater (P < 0.01) than in average endosperm corn. Diets containing corn dried at 120 °C had greater (P < 0.05) ATTD of TDF compared with diets containing corn dried at 35 °C; however, drying temperature did not influence the ATTD of GE. In conclusion, endosperm hardness did not influence the digestibility of AA and starch; however, drying corn at 120 °C reduced digestible AA concentrations. Hard endosperm corn had greater ATTD of GE and TDF, but drying temperature did not influence energy digestibility.

Drying temperatures and corn varieties that inherently differ in kernel hardness, virtuousness, and protein solubility index may influence nutrient digestibility in corn. However, information about interactive effects of corn source (i.e., endosperm hardness) and drying method on nutrient digestibility is limited. Therefore, two experiments were conducted to test the hypothesis that corn source and drying temperature influence energy and nutrient digestibility in corn. Two corn varieties (i.e., average or hard endosperm) were planted in plots with similar soil and similar agronomic conditions and harvested in the same week. Both corn sources were dried at 35 °C or 120 °C. Results indicated that endosperm hardness did not influence the apparent ileal digestibility of starch or standardized ileal digestibility (SID) of amino acids (AA) in pigs; however, values for SID of most AA in corn dried at 120 °C were less than in corn dried at 35 °C. Hard endosperm corn also had greater apparent total tract digestibility of gross energy and total dietary fiber than corn with average endosperm, but drying temperature did not influence energy digestibility. Further research is needed to determine the optimum drying temperature and corn variety to maximize nutritional value in corn.

Metabolizable energy and apparent total tract digestibility of energy and nutrients differ among samples of sunflower meal and sunflower expellers fed to growing pigs.

An experiment was conducted to test the hypothesis that there are no differences among samples of sunflower coproducts in apparent total tract digestibility (ATTD) of gross energy (GE), crude protein (CP), and acid hydrolyzed ether extract (AEE), total dietary fiber (TDF), insoluble dietary fiber, soluble dietary fiber (SDF), or in metabolizable energy (ME) regardless of where the ingredient was produced. Six samples of sunflower meal (SFM) were obtained from the United States (two samples), Ukraine (two samples), Hungary, and Italy. A sample of sunflower expellers (SFE) from the United States was also used. A corn-based control diet and 7 diets containing corn and each sample of sunflower coproducts were formulated. Sixty-four barrows (initial weight = 31.5 ±â€…3.2 kg) were allotted to 8 diets using a randomized complete block design with four blocks of pigs from four different weaning groups. Pigs were housed individually in metabolism crates and feed was provided at three times energy requirement for maintenance. Feces and urine were collected for four days after seven days of adaptation to diets. Results indicated that the ATTD of GE and CP in SFE was less (P < 0.05) than in SFM, but ATTD of AEE in SFE was greater (P < 0.05) compared with SFM. No difference in ME between SFM and SFE was observed. The ATTD of GE and TDF in SFM from Ukraine and Hungary was greater (P < 0.05) than in SFM from the United States or Italy. The ATTD of AEE did not differ among SFM samples with the exception that ATTD of AEE in the U.S. 2 sample was greater (P < 0.05) than in the other samples. The ATTD of SDF was less (P < 0.05) in the U.S. 1 sample and the sample from Italy than in the other samples. The ATTD of TDF was greater in the Ukraine 2 sample of SFM (P < 0.05) than in the two U.S. samples. The ME in the SFM samples from Ukraine and in the SFM from Hungary was greater (P < 0.05) than in the U.S. 1 sample and the SFM from Italy. In conclusion, ATTD of GE and nutrients differed between SFM and SFE, but the ATTD of TDF and the ME in SFM was not different from value for SFE. Among SFM samples, relatively small variations in ATTD of GE, AEE, and CP were observed, but ME and digestibility of TDF varied.

Global oilseed production has been increasing due to the increased demand for oil as well as the increased demand for amino acids for livestock feeding. In addition to providing amino acids, sunflower meal (SFM) and sunflower expellers (SFE) also provide energy and other nutrients to the diets. Because the concentration of residual oil is less in SFM than in SFE, it is expected that SFE provides more energy to diets than SFM. However, data for the digestibility of nutrients and gross energy and concentrations of digestible energy and metabolizable energy in different samples of SFM or SFE are limited. Therefore, the objective of this research was to test the null hypothesis that there are no differences in the apparent total tract digestibility of nutrients and gross energy and concentration of digestible energy and metabolizable energy among SFM and SFE when fed to growing pigs. Results demonstrated that values for apparent total tract digestibility of nutrients and gross energy differed among samples of SFM produced in different countries. However, concentrations of digestible energy and metabolizable energy were not different in SFE compared with SFM despite a greater concentration of fat in SFE.

Inclusion of spray dried plasma in diets based on different ingredient combinations increases the digestibility of energy, fiber, Ca, and P by young pigs.

An experiment was conducted to test the hypothesis that inclusion of spray dried plasma (SDP) in diets increases apparent total tract digestibility (ATTD) and/or the standardized total tract digestibility (STTD) of gross energy (GE) and nutrients in diets for young pigs, and that ATTD of energy and nutrients or STTD of P in individual ingredients are additive in diets containing SDP. Eighty barrows (body weight: 9.30 ± 0.97 kg) were housed in individual metabolism crates and allotted to 1 of 10 diets in a randomized complete block design with 8 replicate pigs per diet. Four diets were prepared without SDP and contained ingredients commonly used in the United States, Canada, the European Union, or Asia. Four additional diets were prepared by mixing 94% of the previous four diets and 6% SDP. A diet containing SDP as the sole source of P and a P-free diet were also formulated. The ATTD of GE and nutrients and the STTD of P were calculated in all diets except the P-free diet and for the four regional diets containing 6% SDP, values were also predicted from the digestibility obtained in SDP alone and the regional diets without SDP. Differences between measured and predicted values for digestibility of GE and nutrients were also calculated. An interaction was observed between SDP and region for the ATTD of soluble dietary fiber where the digestibility decreased (P < 0.05) for pigs fed the U.S. diet with 6% SDP compared with 0% SDP, but that was not the case for the other regional diets. There was no interaction for the ATTD of GE, N, insoluble dietary fiber (IDF), total dietary fiber (TDF), Ca, and P or the STTD of P, but the ATTD and STTD values were greater (P < 0.05) or tended to be greater (P < 0.10%) when 6% SDP was included in the diet compared with diets with 0% SDP. The ATTD of GE, IDF, TDF, and P, and the STTD of P was greater (P < 0.05) for the Asia diet compared with the other diets regardless of inclusion of SDP. The measured ATTD of IDF and TDF was greater (P < 0.05) than the predicted values for the U.S. and European Union diets, and the measured ATTD of GE, N, Ca, and P and the STTD of P was greater (P < 0.05) than the predicted values for the Asia diet. In conclusion, addition of 6% SDP to a diet will increase the ATTD of energy and nutrients and the STTD of P in diets for weanling pigs, and in some cases, the measured ATTD of energy and nutrients or the STTD of P by pigs fed diets containing SDP is greater than predicted from individual ingredients.

Nutritional value of a new source of cheese coproduct fed to weanling pigs.

Three experiments were conducted to test the hypothesis that values for standardized ileal digestibility (SID) of amino acids (AA) and metabolizable energy (ME) in a the cheese coproduct are greater than in fish meal or enzyme-treated soybean meal (ESBM). The second objective was to test the hypothesis that pigs fed a diet containing cheese coproduct will have growth performance that is not different from that of pigs fed other sources of protein. In experiment 1, eight ileal-cannulated barrows (11.0 ± 0.4 kg) were allotted to a replicated 4 × 4 Latin square design with four diets and four periods and two pigs per diet in each period. The four diets included an N-free diet and three diets that contained ESBM, fish meal, or the cheese coproduct as the source of AA. Results indicated that the cheese coproduct had greater (P < 0.05) SID of most AA compared with ESBM and fish meal. In experiment 2, 32 weanling barrows (14.0 ± 1.1 kg) were housed individually in metabolism crates and randomly allotted to one of four diets. A corn-based diet and three diets that contained corn and ESBM, fish meal, or cheese coproduct were formulated. Feces and urine were collected quantitatively. The ME in cheese coproduct was greater (P < 0.05) than in ESBM and fish meal. In experiment 3, 128 weaned pigs (6.2 ± 0.6 kg) were allotted to a randomized complete block design with four treatments and 8 replicate pens per diet. Phase 1 diets that contained 0%, 6.65%, 7.35%, or 14% cheese coproduct were fed from days 1 to 14 and a common phase 2 diet without cheese coproduct was fed from days 15 to 28. Individual pig weights were recorded at the beginning of the experiment, on days 14 and 28, and daily feed allotments were also recorded. Two blood samples were collected from 1 pig per pen on day 14 to analyze for blood urea N, albumin, total plasma protein, peptide YY, immunoglobulin G, tumor necrosis factor-α, interleukin-6, and interleukin-10. No differences were observed in average daily gain among treatments, but there was a tendency (P < 0.10) for total protein on day 14 to increase as cheese coproduct increased in the diets. In conclusion, the cheese coproduct used in this experiment has a greater SID of AA and greater ME than ESBM and fish meal and the cheese coproduct may be included in prestarter diets for weanling pigs without negatively impacting growth performance or indicators of intestinal health.

Milk proteins are highly digestible and have an excellent balance of indispensable amino acids (AA), but the price of dairy products are expensive compared with other protein sources. However, cheese that cannot be used for human consumption may be used in diets for pigs, but there is limited information about the nutritional value of cheese coproducts. Therefore, three experiments were conducted to determine the standardized ileal digestibility of AA, and the metabolizable energy (ME) of a cheese coproduct and effects of inclusion of different levels of cheese coproduct in phase 1 (1 to 14 d postweaning) diets for weanling pigs. Results demonstrated that the cheese coproduct has an excellent digestibility of AA and due to its greater ME than fish meal and enzyme-treated soybean meal, cheese coproduct can be used to increase the energy density of diets for weanling pigs without affecting the health or growth performance of pigs.

Weanling pigs consume more feed if hybrid rye replaces corn in diets, but average daily gain and fecal scores are not impacted by hybrid rye.

An experiment was conducted to test the hypothesis that growth performance and health status of pigs will not be reduced if hybrid rye is included in diets at the expense of corn during the initial 5 wk post-weaning. A total of 128 weanling pigs (5.6 ± 0.5 kg) were randomly allotted to 32 pens and 4 dietary treatments. Pigs were fed experimental diets for 35 d in three phases with days 1 to 7 being phase 1, days 8 to 21 being phase 2, and days 22 to 35 being phase 3. Within each phase, a control diet primarily based on corn and soybean meal was formulated, and three additional diets were formulated by including 8.0, 16.0, or 24.0% (phase 1), 16.0, 32.0, or 48.0% (phase 2), and 20.0, 40.0, or 60.3% (phase 3) hybrid rye in the diet at the expense of corn. Pig weights were recorded at the start and conclusion of each phase, fecal scores were visually assessed every other day on a pen basis, and blood samples were obtained from 1 pig per pen on days 21 and 35. Results indicated that average daily gain (ADG) in phase 1 increased (linear, P < 0.05) as the inclusion of hybrid rye increased, but no other differences in ADG were observed. Average daily feed intake linearly increased in phase 1, phase 3, and overall (P < 0.05) as hybrid rye inclusion increased in the diets, and gain:feed was negatively impacted by the inclusion of hybrid rye in the diet (phase 1, linear, P < 0.05; phases 2, 3, and overall, quadratic, P < 0.05). No differences in average fecal scores or diarrhea incidence were observed. On days 21 and 35, blood urea N increased (linear, P < 0.05) as hybrid rye increased in the diets; and on day 21, serum total protein also increased (linear, P < 0.05) with increasing hybrid rye inclusion in the diet. Mean blood hemoglobin concentration on day 35 increased and then decreased as hybrid rye inclusion increased (quadratic, P < 0.05). On day 21, interleukin (IL) 2 and IL 10 decreased and then increased (quadratic, P < 0.05) as hybrid rye inclusion increased. On day 35, IL 8 and IL 12 increased and then decreased (quadratic, P < 0.05) and interferon-gamma decreased and then increased (quadratic, P < 0.01) as hybrid rye inclusion increased. In conclusion, the ADG of pigs was not different among treatments, but at the highest hybrid rye inclusion level, pigs consumed more feed than if corn was fed and gain:feed was reduced with increasing hybrid rye in diets. Differences in blood serum cytokines indicate the immune system was affected differently when hybrid rye instead of corn was fed.