Apparent Total Tract Digestibility Of CP Research Articles

Prolonged feeding of high-concentrate diet remodels the hindgut microbiome and modulates nutrient degradation in the rumen and the total gastrointestinal tract of cows

The aims of this research were to evaluate how prolonged feeding of a high-concentrate diet affects the ruminal degradation kinetics of fiber and starch, and to evaluate the effects of the high-concentrate diet on apparent total-tract nutrient digestibility in dairy cows. We also investigated the dysbiotic effects and the remodeling of the hindgut microbiome with prolonged high-concentrate feeding. Nine Holstein cows were used in 2 experimental periods; in each period, cows were first fed a 100% forage diet for 1 wk, followed by stepwise adaptation during one week to a high-concentrate (HC) diet (65% concentrate), which was then fed for 4 consecutive weeks. The kinetics of in situ ruminal degradability of grass silage (DM and NDF), corn grain and wheat grain (DM and starch), as well as the apparent total-tract nutrient digestibility were evaluated in the forage feeding and in wk 4 on the HC diet. Whereas the hindgut microbiome and fermentation profile were evaluated on a weekly basis. Regarding the in situ ruminal degradability due to grain type, the rate of degradation of the potentially degradable fraction and the effective rumen degradability of wheat grain were greater compared with corn grain. The in situ ruminal degradability of NDF decreased with the HC diet. However, the apparent total-tract digestibility of CP, fat, starch, NDF, ADF, and NFC increased with the HC diet compared with forage feeding. In addition, the HC diet increased the concentration of short-chain fatty acids in the hindgut, lowering fecal pH by 0.6 units, which correlated positively with microbial α diversity. This resulted in lower α diversity with the HC diet; however, α diversity (number of amplicon sequence variants) showed recovery in wk 3 and 4 on HC; in addition, microbial β diversity did not change from wk 2 onward on the HC diet. Two microbial enterotypes were identified: one for the forage diet with abundance of Akkermansia and Anaerosporobacter, and another enterotype for the HC diet with enrichment in Bifidobacterium and Butyrivibrio. Overall, results show that major microbial shifts and hindgut dysbiosis occurred in wk 1 on the HC diet. However, the hindgut microbial diversity of cows adapted after 3 wk of consuming the starch-rich ration. Thus, feeding the HC diet impaired fiber degradation in the rumen, but increased apparent total-tract nutrient digestibility. Likely, the forage diet contained less digestible NDF than the HC diet due to greater inclusion of forages with lower NDF digestibility and lower inclusion of more digestible nonforage NDF. Results also suggest that the adaptation of the hindgut microbial diversity of cows observed 3 weeks after the diet transition likely contributed to enhance total-tract nutrient digestibility.

Comparative Digestibility of Nutrients, Energy and Dietary Fiber in Feed Ingredients Fed to Philippine Black Tiaong Native (Sus scrofa domesticus) and Hybrid Pigs

The study was carried out to compare the digestibility of nutrients, energy and dietary fiber in conventional feed ingredients fed to Philippine black Tiaong native pigs and hybrid pigs. A total of 18 Philippine black Tiaong native and 18 hybrid pigs (PIC L337 × C24) were randomly allotted to 1 of 3 experimental treatments arranged in a 3 × 6 (black Tiaong native pigs) and 2 × 9 (hybrid pigs) Latin square design. A corn basal diet consisting of 95% corn (as-fed basis) and vitamins and minerals was formulated. The next two diets were formulated by mixing 70% of the basal diet with 30% (as-fed basis) soybean meal and rice bran. The apparent total tract digestibility (ATTD) of nutrients, NDF, ADF and ash and the DE and ME concentration of each ingredient was calculated using the difference procedure. Results showed that ATTD of GE and ME of the diet were greater (P<0.001) for native pigs compared with hybrid pigs. Likewise, the DE and ME of corn, soybean meal and rice bran measured in Philippine black Tiaong native pigs were greater (P<0.001) compared with those measured in hybrid pigs. Philippine black Tiaong native pigs also had greater (P<0.03) ATTD of CP, crude fiber, NDF, ADF, and ash and tended (P=0.08) to have greater ATTD of fat compared with hybrid pigs. The results of this study suggest that Philippine black Tiaong native pigs are more efficient in digesting nutrients as well as their ability to ferment dietary fiber.

Effects of mineral or protein-energy supplementation and genetic group on metabolism parameters of young beef bulls grazing tropical grass during the rainy season

The objective of this study was to evaluate the effects of mineral or protein-energy supplementation and animal genetic groups on rumen fermentation, digestibility and microorganisms of young beef bulls grazing tropical grass during the rainy season. Twelve (nn = 4 per genetic group) ruminally cannulated beef bulls [16 ± 2-months-old and 411 ± 34 kg initial body weight (BW)] were used in a cross-over design, with 4 periods, in a 2 × 3 factorial arrangement. Factors included: 1) two supplementation strategies (SS; mineral supplement [30 g/100 kg BW per day] and protein-energy supplement [300 g/100 kg BW per day]); and 2) three genetic groups (GG; Nellore [NL], ½Angus½Nellore [AN] and Senepol [SN]). Animals were continuously allocated in twelve paddocks composed of Urochloa brizantha (A. Rich.) Stapf. cv. Xaraés for 126 days during the rainy season. Supplementing animals of all GG with protein-energy supplement resulted in an increase of the intake of DM, OM, CP, EE, NFC and ME, and apparent total-tract digestibility of CP and EE. Additionally, animals fed protein-energy supplement showed highest rumen NH3N concentration, microbial-N synthesis, and retained-N. However, a decrease in rumen pH and acetate:propionate ratio was observed when animals were fed protein-energy supplement. Except for Ruminococcus flavefaciens, the relative abundance of total Archaea and Prevotella.spp. were increased when animals where fed protein-energy supplement. Moreover, a GG effect was observed on the relative abundance of total Archaea, Prevotella.spp. and Ruminococcus flavefaciens, which were highest in NL, SN and AN animals, respectively. SN animals fed protein-energy supplement showed an increase of Streptococcus bovis and Selenomonas ruminantium relative abundance, while Fibrobacter succinogenes and Ruminococcus albus were highest in NL animals supplement mineral and protein-energy supplement, respectively. In conclusion, protein-energy supplementation to beef bulls grazing high-quality tropical grass is an effective strategy to increase rumen fermentation during the rainy season. In addition, it modulated rumen microorganism leading to an increase in the relative abundance of Prevotella.spp., Streptococcus bovis and Selenomonas ruminatium, and a decrease in acetate:propionate ratio in Senepol animals.

Interaction of CP levels in maternal and nursery diets, and its effect on performance, protein digestibility, and serum urea levels in piglets

Reduced protein levels in nursery diets have been associated with a lower risk of postweaning diarrhea, but the interaction with CP levels in maternal diet on the performance of the offspring remains unclear. The objective of this study was to determine the effect of protein content in sow gestation and piglet nursery diets on the performance of the piglets until slaughter. This was studied in a 2 × 2 factorial trial (35 sows, 209 piglets), with higher or lower (H or L) dietary CP in sow diets (168 vs 122 g CP/kg) during late gestation. A standard lactation feed was provided for all sows (160 g CP/kg). For both sow treatments, half of the litters received a higher or lower CP in the piglet nursery diet (210 vs 166 g CP/kg). This resulted in four possible treatment combinations: HH, HL, LH and LL, with sow treatment as first and piglet treatment as second letter. For each phase, all diets were iso-energetic and had a similar level of essential amino acids. Ps*p is the p-value for the interaction effect between sow and piglet treatment. In the nursery phase (3.5–9 weeks of age), a tendency toward interaction between piglet and sow treatments with feed efficiency (Ps*p = 0.08) was observed with HH having the highest gain:feed ratio (G:F) (0.74 ± 0.01), LH the lowest (0.70 ± 0.01) and the other two groups intermediate. In the growing-finishing phase, an interaction was observed between the piglet and sow diets with decreased G:F for LH (Ps*p = 0.04) and a tendency toward interaction with increased daily feed intake for LH (Ps*p = 0.07). The sow diet showed a tendency toward a long-lasting effect on the dressing percentage and meat thickness of the offspring, which was higher for the progeny of H sows (Ps < 0.01 and Ps = 0.02, respectively). At 23 weeks, serum urea concentrations tended to be lower for the HH and LL groups (Ps*p = 0.07). Fecal consistency scores were higher at day 10–day 14 after weaning for piglets from L sows (Ps = 0.03 and Ps < 0.01, respectively). At day 7 after weaning, fecal consistency score was higher for piglets fed the higher protein diet (Pp < 0.01). At 8 weeks of age, the apparent total tract digestibility of CP (ATTDCP) interacted between piglet and sow diet (Ps*p = 0.02), with HH showing the highest digestibility values. In conclusion, the protein levels in sow late-gestation and piglet nursery diets interacted with feed efficiency, ATTDCP and serum urea concentrations in the nursery phase.

172 Increasing inclusion of fermentable fiber decreases nutrient digestibility in grower pigs

Abstract Fermentable fiber may increase endogenous losses of P and AA, thereby reducing apparent nutrient digestibility. Acacia gum fiber with medium-to-high fermentability and low viscosity was used to investigate its effect on apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of nutrients, and standardized total tract digestibility (STTD) of P in grower pigs. A P-free basal diet (49% corn starch; 18% bovine plasma protein) was formulated to measure basal endogenous P losses (EPL). Three diets were formulated to include 2.5, 5.0, or 7.5% acacia gum fiber at the expense of corn starch in the P-free basal diet. Diets contained 16.1–17.4% CP and 0.31–0.33% total P (DM-basis). The 4 diets were fed to 8 ileal-cannulated barrows (initial BW, 54.6 kg) for four 9-d periods in a double 4 × 4 Latin square. Apparent hindgut fermentation (AHF) was ATTD minus AID. Increasing inclusion of acacia gum quadratically decreased (P &amp;lt; 0.01) AID of DM (∆ 11.1%), linearly decreased (P &amp;lt; 0.05) ATTD of DM (∆ 1.7%) CP (∆ 1.2%), and quadratically increased (P &amp;lt; 0.05) AHF of DM (∆ 9.4%). Basal EPL were 391 and 377 mg/kg DM intake (DMI) for ileum and total tract, respectively. Increasing inclusion of fiber linearly increased (P &amp;lt; 0.05) ileal EPL (∆ 184 mg/kg DMI), and tended to linearly increase (P &amp;lt; 0.10) EPL for total tract (∆ 243 mg/kg DMI). Dietary inclusion of acacia gum tended to linearly decrease (P &amp;lt; 0.10) AID of P, but did not affect (P &amp;gt; 0.10) ATTD, or STTD of P. In conclusion, increasing inclusion of fermentable, low viscous acacia gum fiber decreased diet digestibility of DM and ATTD of CP, but did not affect total tract P digestibility, indicating that increasing fermentable fiber did not increase specific endogenous losses of P in the total tract.

Use of indirect calorimetry to evaluate utilization of energy in lactating Jersey dairy cattle consuming diets with increasing inclusion of hydrolyzed feather meal

A study using indirect calorimetry and 12 lactating multiparous Jersey cows (53 ± 23 d in milk at the beginning of the experiment; mean ± standard deviation) was conducted to evaluate the utilization of energy in cattle consuming diets containing increasing hydrolyzed feather meal (HFM). A triplicated 4 × 4 Latin square design with 35-d periods (28-d adaption and 4-d collections) was used to compare 4 different dietary treatments. Treatments contained (DM basis) HFM at 0% (0HFM), 3.3% (3.3HFM), 6.7% (6.7MFM), and 10.0% (10HFM). Diets were formulated such that HFM replaced blood meal and nonenzymatically browned soybean meal. With increasing HFM, linear increases were observed for dietary NEL content (1.61, 1.64, 1.69, and 1.70 ± 0.042 Mcal/kg of DM for 0HFM, 3.3HFM, 6.7MFM, and 10HFM, respectively), and the efficiency of converting ME to NEL (0.708, 0.711, 0.717, and 0.719). Apparent total-tract digestibility of CP linearly decreased with increasing HFM (63.4, 61.1, 59.9, and 58.6 ± 1.46% for 0HFM, 3.3HFM, 6.7MFM, and 10HFM, respectively), whereas long-chain fatty acid digestibility increased with increasing HFM (77.2, 77.7, 78.5, and 80.6 ± 1.30%). With increased inclusion of HFM, fecal N excretion increased (199, 230, 239, 237 ± 12.1 g/d for 0HFM, 3.3HFM, 6.7MFM, and 10HFM, respectively), whereas urinary N excretion decreased (166, 151, 155, and 119 ± 14.8 g/d). Increasing the concentration of HFM resulted in a quadratic effect on DMI (19.6, 20.2, 20.3, and 19.1 ± 0.79 kg/d for 0HFM, 3.3HFM, 6.7MFM, and 10HFM, respectively) and milk yield (31.7, 32.0, 31.9, and 29.7 ± 1.32 kg/d). Increasing HFM linearly decreased the milk protein concentration (3.34, 3.29, 3.23, and 3.23 ± 0.158 for 0HFM, 3.3HFM, 6.7MFM, and 10HFM, respectively) and yield (1.05, 1.05, 1.02, and 0.96 ± 0.040 kg). The inclusion of HFM did not affect energy-correct milk yield (average of 39.3 ± 1.54). Results of this study suggest that HFM can increase dietary NEL content compared with blood meal and nonenzymatically browned soybean meal and maintained energy-corrected milk yield; however, feeding HFM at greater than 6.7% of diet DM decreased DMI, and protein availability may have been reduced with increased HFM, leading to a linear decrease in milk protein concentration and yield.

87 Xylanase effects on growth performance, nutrient digestibility, organ weight, and short chain fatty acid concentration in colon digesta of weaned pigs fed wheat and canola meal-based diets

Abstract This study was to determine the effect of dietary supplementation of xylanase on growth performance, nutrient digestibility, organ weight, digesta pH and concentration of short-chain fatty acids (SCFA) of weaned pigs fed wheat-canola meal-based diets over a 35-d period. A total of 144 piglets (6.2 ± 0.7 kg) received one of 8 diets based on a randomized complete block design. Body weight and feed intake were recorded weekly to calculate average daily gain (ADG), average daily feed intake (ADFI), and feed efficiency(G:F). Treatments consisted of a control wheat-SBM-based diet and wheat-regular (RCM), dehulled (DCM) or coarse (CCM) canola meal. All diets contained 500 phytase units (FTUs/kg; Quantum Blue-5G), and titanium-dioxide (0.3%), and were fed without and with 16,000 Birch-Xylan Units of xylanase (BXU/kg; Econase-XT). Apparent total tract digestibilities (ATTD) of NDF, CP, P, Ca, DM, and diet were determined. On d 35, one pig per pen was euthanized to evaluate the effect of treatment on organ weight, digesta pH, and digesta concentration of SCFA. Treatment did not affect growth performance. Xylanase supplementation improved nutrient digestibilities, without affecting growth performance. The ATTD of NDF was greater (P &amp;lt; 0.05; 48%) in the wheat-SBM+xylanase, wheat-SBM without xylanase (46%), and DCM+xylanase (45%) diets. The ATTD of CP was greater (P &amp;lt; 0.05; 78%) in wheat-SBM+xylanase, and wheat-DCM+xylanase (75%), diets. Xylanase supplementation increased ATTD of P and Ca by 9 and 19%; whereas ileum and colon digesta pH increased by 6 and 3%. Supplementing xylanase to DCM increased butyric acid by 10%, whereas the concentration of acetic acid increased by 24% in colon-digesta of pigs fed CCM+xylanase. In conclusion, dietary supplementation of xylanase increased nutrient digestibilities, digesta pH without affecting growth performance of weaned pigs fed wheat and canola meal-based diets. Additionally, supplemental xylanase increased butyric acid concentration in colon digesta of pigs fed wheat-DCM diets.

Effects of Dietary Aged Maize with Oxidized Fish Oil on Growth Performance, Antioxidant Capacity and Intestinal Health in Weaned Piglets.

Simple SummaryIn China, large quantities of maize are stored in grain depots for two years or more to mitigate the risk of natural disasters impacting feed supplies. However, it is unknown whether the use of long-term stored maize in diets will impair growth performance of piglets, and whether additional dietary oxidants would further exacerbate the effects. This study investigates the effects of dietary aged maize with the supplementation of different levels of oxidized fish oil on growth performance, nutrient digestibility, serum antioxidant activity and gut health in piglets and tries to provide a theoretical foundation for the better use of aged maize in swine production. The results of this study showed that aged maize had no significant effect on growth performance, diarrhea and nutrient digestibility of the piglets, but it did reduce serum antioxidant capacity. When oxidized fish oil was added, aged maize reduced serum antioxidant capacity further, inhibited the expressions of genes related to intestinal nutrient transport, promoted intestinal inflammation, and also reduced the apparent total tract digestibility (ATTD) of nutrients, increased diarrhea and finally reduced the growth performance of piglets. Thus, the use of aged maize in the diet of the piglets may be not feasible, especially when other oxidation-inducing factors existed, which would exacerbate the negative effects of the aged maize.This study aimed to determine the effects of dietary aged maize with supplementation of different levels of oxidized fish oil on growth performance, nutrient digestibility, serum antioxidant activity and gut health in piglets. Forty-two piglets were arranged in 2 × 3 factorial treatments in a complete randomized block design with seven replicates per treatment and one pig per replicate for 28 d. Diets included twp types of maize (normal maize or aged maize) and three levels of oxidized fish oil (OFO) (3% non-oxidized fish oil (0% OFO), 1.5% OFO and 1.5% non-oxidized fish oil (1.5% OFO), and 3% OFO (3% OFO). Results showed that dietary aged maize did not affect growth performance, diarrhea, and the apparent total tract digestibility (ATTD) of nutrients in piglets (p > 0.05). However, aged maize increased malonaldehyde (MDA) content and decreased total antioxidant capacity (T-AOC) in serum on both 14th and 28th days (p < 0.05) compared to the normal maize groups. Meanwhile, compared with normal maize, dietary aged maize showed a slight, but not significant (p > 0.10) decrease in total superoxide dismutase (T-SOD) activity and VE content in serum on the 14th day. In addition, aged maize significantly decreased GLUT2 mRNA expression (p < 0.05) and tended to increase (p < 0.10) TNF-α and IL-6 mRNA expression in jejunal mucosa. Compared with non-oxidized fish oil, oxidized fish oil resulted in the decrease of the 14–28 d and 0–28 d ADG, as well as the ATTD of dry matter (DM), ether extract (EE), organic matter (OM) (p < 0.05), whereas the increase in diarrhea index (p < 0.05) and F/G of the whole period (p < 0.05). Oxidized fish oil decreased serum T-AOC on both the 14th and the 28th days (p < 0.05), and decreased serum T-SOD activity and VE content on the 28th day (p < 0.05), whereas increased serum MDA content on the 28th day (p < 0.05) and 14th day (p < 0.10) compared with fresh fish oil. Meanwhile, MUC2 (p < 0.05) and SGLT1 (p < 0.10) mRNA expression in jejunal mucosa were decreased compared with non-oxidized fish oil. In addition, dietary oxidized fish oil tended to decrease 14–28 d ADFI and the ATTD of CP (p < 0.10), and piglets fed oxidized fish oil significantly decreased 14–28 d ADFI, the ATTD of CP, GLUT2 and SGLT1 mRNA expressions in jejunal mucosa when piglet also fed with aged maize (p < 0.05). Collectively, these results indicated that dietary oxidized fish oil decreased growth performance and nutrients digestibility of piglets fed with aged maize. This nutrient interaction may be mediated by inhibiting intestinal nutrient transporter, inducing intestinal inflammation, and reducing antioxidant capacity.

Antimicrobial peptide KR-32 alleviates Escherichia coli K88-induced fatty acid malabsorption by improving expression of fatty acid transporter protein 4 (FATP4)1.

Bacterial infection causes nutrient malabsorption in small intestine. KR-32, a kind of synthetic antimicrobial peptide, has the bacteriostatic effect. In the present study, 2 experiments were designed to analyze the effects of KR-32 on fat absorption of piglets with or without Escherichia coli infection. In Exp. 1, 12 weaning piglets (21 d old) were allocated to 2 groups: piglets with an intraperitoneal (i.p.) injection of antimicrobial peptide KR-32 (APK) and piglets with an i.p. injection of an equivalent volume (1 mL) of phosphate-buffered saline (PBS) (CON-1). Results showed that after 7 d of growth, KR-32 did not significantly change growth performance and apparent total tract digestibility (ATTD) of feed nutrients of normal pigs. To confirm whether KR-32 affects those of enterotoxigenic Escherichia coli (ETEC) K88-challenged pigs, we performed Exp. 2, in which 18 piglets (28 d old) were divided into the following 3 groups: 1) piglets orally challenged with 1 × 1010 cfu ETEC K88 on day 1 followed by an i.p. injection of 0.6 mg/kg KR-32 (K88 + APK); 2) piglets orally challenged with 1 × 1010 cfu ETEC K88 on day 1 followed by an i.p. injection of an equivalent volume (1 mL) of PBS (K88); and 3) piglets with an oral administration of fresh Luria-Bertani broth (50 mL) followed by an i.p. injection of an equivalent volume of PBS (CON-2). Results showed that ETEC K88 challenge led to poor ADFI, ADG, and G:F in piglets; decreased ATTD of feed nutrients, especially CP and ether extract (EE); and intestinal morphology disorder. After i.p. injection of KR-32, ADG and ATTD of CP and EE were greatly increased, G:F was significantly reduced (P < 0.05), and, especially, ATTD of EE returned to a normal level compared with group CON-2. Fatty acid absorption also highly increased after KR-32 injection. Then we focused on fat digestion and fatty acid uptake. The pH in the intestine and pancreas lipase showed no difference among the 3 treatment groups, whereas fatty acid transporter protein 4 (FATP4) expression was remarkably improved (P < 0.05) and the epithelial barrier was recovered after i.p. injection of KR-32. In conclusion, KR-32, given to ETEC K88-challenged piglets, improved growth performance, ATTD of EE, fatty acid absorption, and intestinal morphology, which indicated that KR-32 was likely to improve the expression of FATP4 and by repairing the epithelial barrier, thereby alleviating fatty acid malabsorption.

Effect of tannins and cellulase on growth performance, nutrients digestibility, blood profiles, intestinal morphology and carcass characteristics in Hu sheep.

ObjectiveThis study was conducted to evaluate the effects of tannins and cellulase on growth performance, nutrient digestibility, blood profiles, intestinal morphology, and carcass characteristics in Hu sheep.MethodsA total of 48 three-month-old meat Hu sheep (25.05±0.9 kg) were blocked based on body weight, and randomly allotted to 4 treatments with 3 replicates of 4 sheep each. The experiment lasted for 80 d, and dietary treatments were as follows: i) CON, control diet; ii) TAN, CON+0.1% tannins; iii) CEL, CON+0.1% cellulase; iv) TAN+CEL, CON+0.1% tannins and 0.1% cellulase.ResultsCompared with CON, CEL, and TAN+CEL had greater (p<0.05) final body weight (FBW) and average daily gain but lower (p<0.05) feed conversion ratio, while FBW of TAN+ CEL was lower (p<0.05) than that of CEL. The apparent total tract digestibility (ATTD) of dry matter in TAN, CEL, and TAN+CEL groups were higher (p<0.05) than that in CON. CEL and TAN+CEL groups had greater (p<0.05) ATTD of crude fiber compared with TAN and CON, while TAN group had lower (p<0.05) ATTD of crude protein than other treatments. TAN, CEL, and TAN+CEL groups increased (p<0.05) serum globulin and alkaline phosphatase but decreased (p<0.05) albumin/globulin. Serum total protein was greatest for TAN+CEL, intermediate for TAN and CEL and least for CON (p<0.05). TAN+CEL group increased (p<0.05) dressing percentage compared with CON, while the backfat thickness of CEL was lower (p<0.05) than that of CON. The villus height of jejunum and ileum in CEL and TAN+CEL groups were greater (p<0.05) than that in CON, and the crypt depth and villus height: crypt depth of jejunum were increased (p<0.05) in TAN, CEL, and TAN+CEL groups.ConclusionThe addition of tannins and cellulase together promoted nutrient digestion, liver protein synthesis and intestinal development and thus improved growth performance and carcass characteristics.

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.

Rapid Communication: The relationship of enterocyte proliferation with intestinal morphology and nutrient digestibility in weaning piglets

Understanding the regulatory mechanisms of intestinal morphology and function is essential for improving postweaning growth in pigs. The objective of this study was to identify the relationships of enterocyte proliferation with intestinal villus height, crypt depth, and nutrient digestibility in piglets. Sixty-four 21-d-old weaned piglets were used. Gastrointestinal cell proliferation was evaluated via Ki-67 immunohistochemistry. Villus height and crypt depth were measured using hematoxylin and eosin (H&E)-stained sections. The apparent total tract digestibility (ATTD) of CP and GE was determined by chemical analysis. The activities of lactase and sucrase were determined with commercial kits. Western blot was carried out to assess the expression of nutrient transporters. The number of Ki-67 positive cells was associated with villus height (r = 0.548, P < 0.001) and crypt depth (r = 0.759, P < 0.001) in the jejunum. The number of Ki-67 positive cells was also associated with the ATTD of CP (r = 0.715, P = 0.001). Furthermore, a positive relationship between Ki-67 positive cell populations and lactase activity (r = 0.559, P < 0.001) was observed. Additionally, the number of Ki-67 positive cells was associated with the protein expression levels of nutrient transporters PEPT1 (r = 0.511, P = 0.030) and SGLT1 (r = 0.601, P = 0.014). Weak relationships were found between Ki-67 positive cell numbers and the ATTD of GE (r = 0.401, P = 0.099) and the activity of sucrase (r = 0.313, P = 0.087). In conclusion, enterocyte proliferation was positively associated with intestinal villus height, crypt depth, and nutrient digestibility in weaning piglets. Our findings suggested that intestinal morphology and function can be improved by regulating epithelial cell proliferation in piglets.

Growth performance, gastrointestinal and digestibility responses in growing pigs when fed corn-soybean meal-based diets with corn DDGS treated with fiber degrading enzymes with or without liquid fermentation.

Fermenting high fiber ingredients such as distillers dried grains with solubles (DDGS) with feed enzymes may improve their feeding value. We investigated the effects of fermenting corn DDGS with a blend of β-glucanase and xylanases (XB) on growth performance, gut parameters, and apparent total tract digestibility (ATTD) of nutrients and energy in growing pigs. Dietary treatments were: (1) corn soybean meal-based diet + 30% DDGS (control), (2) control + XB without fermentation (XBNS), and (3) control + DDGS fermented with XB (16% DM) for 3 to 10 d at 40 °C (XBS). Target activities in XB were 1,050 and 5,500 U/g of DDGS for XB, respectively. Diets contained phytase at 750 FTU/kg. Feed samples were taken during fermentation and at feeding for analysis of pH and organic acids. A total of 144 pigs (25 ± 1.0 kg BW) were assigned to pens (three barrows and three gilts) and allocated to the three diets in a two-phase feeding program (3 wk/phase). Diets were fed on ad libitum and were delivered by a computer-controlled liquid feeding system at a feed to water ratio of 1:4, four times per day. Pigs had free access to water. Fecal samples were taken in the final 3 d of phase 2 to determine ATTD using TiO2 marker method and one pig per pen was euthanized for gastrointestinal (GIT) measurements. The pH of diets at feeding time was lower (P < 0.01) for XBS (4.72) compared with control (5.45) and XBNS (5.45). Pigs fed XBNS had higher (P = 0.04) ADG than control in phase 1. In phase 2 and the overall (weeks 0 to 6), ADG and final BW were higher (P = 0.01) for XBNS than XBS but were not different (P > 0.05) from control. There were no diet effects (P > 0.05) on ADFI. Feed to gain (FCR) for XBNS (1.68) and XBS pigs (1.69) was better (P < 0.01) than for control pigs (1.78) in phase 1. There were no diet effects (P > 0.05) on FCR in phase 2 or in the overall. Pigs fed XBNS had lower (P < 0.01) ATTD of CP than control and XBS-fed pigs. Although not different (P > 0.05) from control, pigs fed XBNS had lower (P < 0.05) jejunal crypt depth and ATTD of gross energy than pigs fed XBS. In conclusion, treating corn DDGS with XB with or without liquid fermentation improved feed efficiency in phase 1, suggesting degradation of dietary fibrous components that may limit nutrient utilization in younger pigs. However, these benefits were not observed in phase 2.

Effects of adaptation time and inclusion level of sugar beet pulp on nutrient digestibility and evaluation of ileal amino acid digestibility in pigs

ObjectiveTwo experiments were conducted to determine the effects of adaptation time and inclusion level of sugar beet pulp (SBP) on nutrient digestibility and to evaluate the ileal amino acid digestibility of SBP fed to pigs.MethodsIn Exp. 1, thirty-six crossbred barrows (85.0±2.1 kg) were allotted to 6 diets in a completely randomized design with six replicates per diet. Diets included a corn-soybean meal diet and 5 test diets containing 14.6%, 24.4%, 34.2%, 43.9%, or 53.7% SBP, respectively. The adaptation time consisted 7, 14, 21, or 28 d consecutively for each pig followed by 5 d for fecal collection. Feces were collected from d 8 to 13, d 15 to 20, d 22 to 27, and d 29 to 34, respectively. In Exp. 2, six pigs (35.1±1.7 kg) with T-cannulas at the terminal ileum were fed to 3 diets in a replicated 3×3 Latin square design with 3 periods and 2 replicate pigs per diet. Each period consisted 5 d for diet adaptation followed by 2 d for digesta collection.ResultsThe digestible energy (DE) value and the apparent total tract digestibility (ATTD) of gross energy (GE), dry matter (DM), ash, and organic matter in diets linearly decreased (p< 0.05) as the adaptation time increased or as the dietary SBP increased, while the ATTD of neutral detergent fibre and acid detergent fibre in diets linearly increased (p<0.01) as the dietary SBP increased. The DE value and the ATTD of GE and crude protein (CP) in SBP linearly increased (p<0.05) as the adaptation time increased, while the ATTD of CP in SBP linearly decreased (p<0.01) as the inclusion level increased. The standardized ileal digestibility of Lys, Met, Thr, and Trp in SBP was 37.03%, 51.62%, 40.68%, and 46.22%, respectively.ConclusionThe results of this study indicated that the ATTD of energy and nutrients were decreased as inclusion rate of SBP increased.

Endogenous fat loss and true total tract digestibility of poultry fat in adult dogs.

Fat plays an important role in the carnivore diet. It has high digestibility and high energy content and likely improves digestibility of the diet when present in greater amounts, suggesting that endogenous fat adversely affects the apparent digestibility of fat in low-fat diets. This study aimed to determine the endogenous fat loss (EFL) and true total tract digestibility (TTTD) of fat in dogs by using diets having different fat:carbohydrate ratios. Furthermore, the apparent total tract digestibility (ATTD) of macronutrients and energy, food intake, fecal output, and stool quality were evaluated. Twelve adult Beagle dogs were stratified into three 10-d periods in a 6 × 3 balanced incomplete Latin square design. Dietary treatments included a low-fat basal diet (3.4% fat) supplemented with 6 poultry fat levels (1, 4, 10, 12, 16, or 20%). The dogs were individually housed in metabolic cages and fed to meet the maintenance energy requirements. The ME intake was similar across the diets, despite the clearly low palatability of the 1 and 4% fat diets. Dietary ATTD of DM, OM, fat, and GE were improved after fat inclusion ( < 0.001). The ATTD of CP was not affected by dietary fat increase ( > 0.05). The amount of fecal output decreased with increasing level of fat in the diet, but the fecal score was not affected. The stool quality was close to ideal (2.4-2.8) and no different among diets. The EFL was estimated using 2 regression methods and was expressed as 155 mg∙kg BW∙d or 7.9 g/kg of DMI. The TTTD of poultry fat was the same irrespective of the dietary fat level. Poultry fat was 99.3% digestible for the dogs. The relation between EFL and fat intake was higher for the lower-fat diets, explaining the ATTD of fat increase according to the dietary fat inclusion. In conclusion, dietary fat is well digested by dogs irrespective of the level included, close to 100%. The ATTD of fat in low-fat diets is underestimated because the endogenous content is proportionally greater than that in high-fat diets.

Effects of feeding camelina cake to weaned pigs on safety, growth performance, and fatty acid composition of pork.

Feeding cake with remaining oil contributes dietary energy (fat) in addition to protein (AA) and may provide an opportunity to enrich the n-3 fatty acid content of pork. Information regarding safety, growth performance, and efficacy of feeding camelina cake to pigs is limited. We therefore evaluated the effects of camelina cake inclusion in pig nursery diets. In total, 192 pigs (9.4 kg BW) were randomly allocated by sex to 48 pens, 2 heavy and 2 light pigs per pen. Pigs were fed 1 of 4 wheat-based diets including camelina cake (0%, 6%, 12%, or 18%; variety Celine) replacing soybean meal for 4 wk. Individual pigs, pen feed added, and orts were weighed weekly. Feces were collected on d 26 and 27. A blood sample was taken on d 29 from 24 pigs with the lowest BW/pen, which were then euthanized and necropsied. Gross pathological examination was conducted, and organ weights were measured. Samples of liver, back fat, belly fat, and jowl fat were collected for fatty acid analysis. Increasing dietary camelina cake inclusion linearly decreased ( 0.001) apparent total tract digestibility (ATTD) of DM, OM, GE and ash but did not affect ATTD of CP and P. For the entire trial (d 0 to 28), increasing camelina cake inclusion by 6% linearly decreased ( 0.001) ADFI by 74 g/d, ADG by 51 g/d, and BW by 0.8 kg but did not affect feed efficiency (G:F). Increasing camelina cake inclusion linearly increased ( 0.001) liver weight relative to BW, linearly decreased ( 0.050) kidney weight, but did not affect spleen, heart, and thyroid weights. Increasing camelina cake inclusion did not result in serological (large-animal standard panel, T3, and T4) or gross clinical (morphology) findings that might suggest toxicity. In liver, back fat, belly fat, and jowl fat, increasing dietary camelina cake inclusion linearly increased ( 0.050) total n-3 fatty acids and shorter-chain n-3 and n-6 fatty acids but did not increase docosahexaenoic acid (n-3) or arachidonic acid (n-6). In conclusion, feeding camelina cake to weaned pigs at up to 18% did not elicit clinical signs of toxicity and increased n-3 fatty acids in carcass fat depots. The decrease in ADFI as camelina cake inclusion increased resulted in pigs fed 18% weighing 5 kg less than controls at the end of the nursery period.

Effects of feed intake and dietary nutrient density on apparent ileal and total tract digestibility of nutrients and gross energy for growing pigs.

The present study was conducted to investigate the effects of feed intake (FI) and dietary nutrient concentration on the determination of apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of nutrients and GE for growing pigs. A total of 48 growing pigs (40.7 ± 1.3 kg initial BW) were surgically fitted with simple T-cannulas at the distal ileum and assigned to 6 treatment groups in a 2 × 3 factorial arrangement of 2 diets (a low-nutrient-density [LND] diet or a normal-nutrient-density [NND] diet) and 3 FI levels (3, 4 or 5% of BW per day). The experimental period consisted of a 5-d adjustment period: 2 d of feces collection (on d 6 and 7), and 2 d of ileal digesta collection on (d 8 and 9). Chromic oxide was used as an indigestible marker to calculate AID of AA and AID and ATTD of CP, ether extract (EE), ash, ADF, NDF, total carbohydrates (CHO), and GE. The AID of CP ( < 0.05), EE ( < 0.1), ash ( < 0.05), and GE ( < 0.1); the ATTD of ash ( < 0.1); and the hindgut disappearance of CP ( < 0.05), ash ( < 0.1), and most AA were affected by the interaction of dietary nutrient density and FI level. The AID of CP and the AID and ATTD of DM, EE, CHO, and GE linearly decreased for pigs fed a NND diet as FI increased ( < 0.05). Furthermore, the AID of CHO ( < 0.1) and NDF ( < 0.05), the ATTD of DM ( < 0.1), and the hindgut disappearance of CHO and NDF ( < 0.1) were influenced by FI. When pigs were fed the NND diet, the AID of most AA decreased (linear, < 0.05) with increasing FI. However, there were no linear or quadratic effects of FI levels on the AID, ATTD, and the hindgut disappearance of DM, CP, EE, CHO, NDF, ADF, and GE and the AID of most AA for pigs fed the LND diet. In summary, the AID and ATTD of nutrients and GE response of growing pigs to FI levels are dependent on dietary nutrients density. The AID and ATTD of nutrients and GE decreased for pigs fed the NND diet as FI increased.

Protein and amino acid bioavailability of extruded dog food with protein meals of different quality using growing mink () as a model.

The present study evaluated growing mink () as a model for dietary protein quality assessment of protein meals used in extruded dog foods. Three foods with similar CP content but of different protein quality were produced using different protein meals. The protein meals varied with respect to CP digestibility and AA composition and included lamb meal (LBM), poultry meal (PM), and fish meal (FM) with low, intermediate, and high protein quality, respectively. Nitrogen balance, BW gain, protein efficiency ratio (PER), and apparent total tract digestibility (ATTD) were used as measures of protein and AA bioavailability in growing mink. Standardized ileal digestibility (SID) was used to measure protein and AA bioavailability in adult dogs (). The mink study (3 × 3 Latin square design) included 12 kits aged 8 to 11 wk. The dog study included 12 dogs divided in 3 groups allocated to 1 of the experimental diets. The growing mink responded in accordance with the different AA supply between diets, as determined by the first limiting AA. The LBM diet deviated from the other diets with lower ( < 0.001) values for N retention, BW gain, and PER, and the diets differed ( < 0.001) in ATTD of CP and all AA, except for hydroxyproline. Retention of N was 0.66, 1.04, and 1.18 g·kg·d; BW gain was 8.2, 26.8, and 35.3 g/d; PER was 0.38, 1.39, and 1.71; and ATTD of CP was 66.8, 73.8, and 82.1% for the LBM, PM, and FM diets, respectively. In dogs, SID of CP and AA differed ( ≤ 0.017) between diets and was generally lowest for the LBM diet, intermediate for the PM diet, and greatest for the FM diet. For CP, SID was 71.5, 80.2, and 87.0% for the LBM, PM, and FM diets, respectively. The contents of digestible CP and AA (based on SID) covered the minimal requirement for adult dogs set by the NRC for all diets, except for the content of digestible Met + Cys in the LBM diet. Despite this, dietary content of Met + Cys in the LBM diet agreed with the recommended level set by the NRC and the Association of American Feed Control Officials for adult dogs but was below the level recommended by the European Pet Food Industry Federation. It was concluded that growth studies with mink kits can provide valuable information in protein quality assessment of extruded dog foods. Furthermore, the study showed that to ensure nutritional adequacy of dog food and to be able to compare protein quality of dog foods, information on AA composition and digestibility is crucial.

Effects of a Bacillus-based probiotic and dietary energy content on the performance and nutrient digestibility of wean to finish pigs

The study was conducted to determine the effects of a Bacillus-based probiotic (mixture of spray-dried spore-forming Bacillus licheniformis (DSM 5749) and Bacillus subtilis (DSM 5750)) supplementation and different diet energy densities on growth performance and nutrient digestibility in wean-to-finish pigs. A total of 576 weaned piglets with initial body weight (BW) of 7.1±1.1kg were used. Pigs were randomly allotted to 1 of 4 treatments in a 2×2 factorial arrangement of treatments with 2 levels of energy (standard and reduced (∼3% less in calculated NE)) and 0 or 400mg/kg of the Bacillus-based probiotic according to their sex and BW (6 male and 6 female replicates per treatment, with 12 pigs each). During the prestarter period (28–42d), there were no treatment effects on growth performance. For the starter period (42–70d) pigs on the probiotic treatments grew significantly faster and tended to have a better feed:gain (F:G) than their control counterparts. During the same period pigs offered the standard energy diet exhibited significantly better F:G than those offered the lower energy diet. During the grower period (70–120d), the probiotic significantly improved growth rate by 11.2% and F:G by 8.6% with the proportional change in F:G being much higher for pigs offered the lower energy diet. During the finisher period (120–182d), the probiotic had a negative effect on F:G (P=0.047). Over the whole period (28–182d), probiotic supplementation significantly improved growth and F:G. In addition, pigs receiving the standard energy diet exhibited improved F:G compared to pigs receiving the lower energy diet. Probiotic supplementation increased fat and phosphorus (P) apparent total tract digestibility (ATTD). Pigs fed the lower energy diets exhibited significantly higher ATTD of DM, CF and P, but lower ATTD of fat than pigs fed the standard energy diets. Probiotic increased CP ATTD under lower but not under the standard level of energy and was effective in improving Ca ATTD in the standard but reduced it on the lower energy diet. In conclusion, dietary supplementation of the Bacillus-based probiotic improved growth and F:G from weaning to slaughter, and exerted beneficial effects on ATTD of fat and P in the growing period. Major effects were observed in the starter and grower periods suggesting that strategy might be best targeted to pigs between 42–120d. Even though probiotic improved pig performance, the response varied with energy density of diets in the case of F:G in the grower period and ATTD of CP and Ca.

A new phytase continuously hydrolyzes phytate and improves amino acid digestibility and mineral balance in growing pigs fed phosphorous-deficient diet.

Ten ileal T-cannulated pigs (19.26 ± 1.06 kg) were used to evaluate the effects of a novel phytase on apparent ileal digestibility (AID) of AA and apparent total tract digestibility (ATTD) and hindgut disappearance of DM, GE, CP, crude fiber, NDF, and ADF as well as minerals balance. Pigs were fed in a duplicated 5 × 4 incomplete Latin square design (5 diets with 4 periods). Each period consisted of a 5-d adjustment period followed by a 3-d total collection of feces and urine and then a 2-d collection of ileal digesta. The 5 diets included a P-deficient basal diet (0.43% Ca and 0.38% total P) that was supplemented with 0 (negative control [NC]), 500, 1,000, or 20,000 phytase units (FTU)/kg phytase and a positive control (PC) diet that was P adequate (0.64% Ca and 0.52% total P). The addition of phytase to the NC diet improved ( < 0.05) AID of phytate from 11.1 to 62.8, 70.6, and 90.5% at the inclusion rates of 500, 1,000, and 20,000 FTU/kg, respectively. In general, phytase supplementation at a dose of 20,000 FTU/kg further increased ( < 0.05) AID of Ca, total P, and phytate and reduced ( < 0.05) the ileal phytate concentration compared with diets with 500 or 1,000 FTU/kg phytase. Pigs fed the diet with 20,000 FTU/kg phytase but not diets with 500 and 1,000 FTU/kg phytase showed improved ( < 0.05) ATTD of CP and AID of DM, GE, CP, Leu, Lys, Thr, Val, Asp, and Ser compared with pigs fed the PC or NC diet. However, hindgut disappearance of crude fiber and NDF ( < 0.05) were reduced in pigs fed the diet with 20,000 FTU/kg phytase compared with pigs fed the PC or NC diet. Pigs fed diets with 500 or 1,000 FTU/kg phytase had greater ATTD and retention of Ca and P than pigs fed the NC diet but less compared with pigs fed the diet with 20,000 FTU/kg phytase. Supplementation of 20,000 FTU/kg phytase to the NC diet improved ( < 0.05) digestibility of Na, Mn, and Zn as well as retention (%) of Zn. Increasing phytase supplementation doses from 0 to 1,000 FTU/kg linearly improved ( < 0.05) retention of Mg; meanwhile, digestibility of Mg and Mn and AID of Thr showed a linear increase trend ( = 0.084). In conclusion, supplementation of the novel phytase at doses up to 20,000 FTU/kg hydrolyzed most of the phytate (90%) and consequently further improved mineral and protein utilization.