Endogenous Losses Research Articles

Comparison of Methods for Estimating Basal Endogenous Losses of Amino Acids; Additivity of Amino Acids Digestibility in Corn and Soybean Meal for Broilers

Comparison of Methods for Estimating Basal Endogenous Losses of Amino Acids; Additivity of Amino Acids Digestibility in Corn and Soybean Meal for Broilers

Effects of extrusion on ileal and total tract digestibility of nutrients and energy in soybean for weanling pigs

This study evaluated the ileal and total tract digestibility of nutrients and energy in soybean extruded at three different conditions, compared to deactivated soybean (DS), in newly weaned piglets. Forty crossbred barrows (28 d old and 7.64 ± 0.88 kg body weight) were allotted to 5 dietary treatments with 8 replications per treatment. The diets consisted of an N-free diet, to determine endogenous losses of amino acids (AA), and 4 diets containing 30% of test ingredients as the only source of protein and AA: soybean extruded at 82 °C (SB82), 122 °C (SB122) and 137 °C (SB137), and DS, which was used as a control. The DS was produced by heating the whole raw soybean, from 63 °C to 107 °C under pressure. Titanium dioxide was added to the diets as an indigestible marker. After a 5 d adaptation period, partial feces collection was performed over 5 d and samples of ileal digesta were collected after piglets euthanasia. The apparent total tract digestibility of dry matter, gross energy (GE), crude protein (CP), neutral detergent fiber and acid detergent fiber, and apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of CP and AA were evaluated. Analysis of variance was performed and the means compared by Tukey test when P < 0.05. The extrusion of soybean at 122 °C and 137 °C was effective in reducing trypsin inhibitors content, and promoted adequate nutrient and energy digestibility of soybean in piglets. These effects could be observed as the AID of Lys and Trp, and SID of Lys of SB122 and SB137 were greater (P < 0.05) than those of SB82 and DS. The AID and SID of CP and remaining AA were similar among SB122, SB137 and DS, but greater (P < 0.05) than those of SB82. In addition, the ATTD of GE of SB122 was 3–4% greater (P < 0.05) than those of DS and SB82, showing an important effect of extrusion on energy use by pigs. Thus, extrusion of soybean at 122 °C is recommended and SB122 is a feed ingredient with greater nutritional value than DS or SB82 for young pigs.

228 Standardized Ileal Digestibility of Partially Defatted Black Soldier Fly Larvae Meal in Growing Pig Diets

Abstract New ingredients need to be characterized both chemically and in vivo, then compared to commonly-used protein ingredients before they can be considered for use in feeds. The objective of the present study was to determine the standardized ileal digestibility (SID, %) of amino acids (AA) of partially defatted black soldier fly larvae meal (BSFLM) (49.7% CP; 14.4% crude fat as fed). Subsequently, these results were compared to the SID AA of common protein ingredients in swine feed, fish meal (FM) and soybean meal (SBM) (NRC 2012), and to published full-fat (FF) BSFLM SID values. Six ileal-cannulated barrows (18.03 ± 0.67 kg BW) were used in a 2x2 Latin square design and fed either a nitrogen-free diet (NFD) or BSFLM-containing diet over two 11-d experimental periods. In each period, barrows were adapted for 7 days to the diet and ileal digesta collection was conducted on day 10 and 11 for 8h per day. Basal endogenous AA losses (EAAL) were calculated from pigs fed the NFD and as expected, the ileal AA content were significantly higher for pigs fed the BSFLM diet than NFD (P &amp;lt; 0.05). SID for AA were then calculated based on the obtained EAAL values following Stein et al., 2007. For essential AA, the SID of BSFLM were all above 82%, the highest being Arg (93.76%), followed by Met (91.32%), and Phe (89.80%). The SID of essential AA were on average 5.0% higher in BSFLM than FM, but 2.7% lower than SBM. When compared to the FF BSFLM, SID of essential AA of BSFLM were 1–5% higher, except for Phe and Thr. These results suggest that partially defatted BSFLM is a promising alternative protein ingredient in growing pig diets, which has a more digestible AA profile than FM, only slightly lower than SBM, and comparable to the FF BSFLM.

Development and Functional Properties of Intestinal Mucus Layer in Poultry.

Intestinal mucus plays important roles in protecting the epithelial surfaces against pathogens, supporting the colonization with commensal bacteria, maintaining an appropriate environment for digestion, as well as facilitating nutrient transport from the lumen to the underlying epithelium. The mucus layer in the poultry gut is produced and preserved by mucin-secreting goblet cells that rapidly develop and mature after hatch as a response to external stimuli including environmental factors, intestinal microbiota as well as dietary factors. The ontogenetic development of goblet cells affects the mucin composition and secretion, causing an alteration in the physicochemical properties of the mucus layer. The intestinal mucus prevents the invasion of pathogens to the epithelium by its antibacterial properties (e.g. β-defensin, lysozyme, avidin and IgA) and creates a physical barrier with the ability to protect the epithelium from pathogens. Mucosal barrier is the first line of innate defense in the gastrointestinal tract. This barrier has a selective permeability that allows small particles and nutrients passing through. The structural components and functional properties of mucins have been reviewed extensively in humans and rodents, but it seems to be neglected in poultry. This review discusses the impact of age on development of goblet cells and their mucus production with relevance for the functional characteristics of mucus layer and its protective mechanism in the chicken’s intestine. Dietary factors directly and indirectly (through modification of the gut bacteria and their metabolic activities) affect goblet cell proliferation and differentiation and can be used to manipulate mucosal integrity and dynamic. However, the mode of action and mechanisms behind these effects need to be studied further. As mucins resist to digestion processes, the sloughed mucins can be utilized by bacteria in the lower part of the gut and are considered as endogenous loss of protein and energy to animal. Hydrothermal processing of poultry feed may reduce this loss by reduction in mucus shedding into the lumen. Given the significance of this loss and the lack of precise data, this matter needs to be carefully investigated in the future and the nutritional strategies reducing this loss have to be defined better.

Contribution of purified soybean trypsin inhibitor and exogenous protease to endogenous amino acid losses and mineral digestibility

The primary objective of the current study was to evaluate the impact of trypsin inhibitor (TI) and exogenous protease supplementation on endogenous loss of amino acids (AA) in broiler chickens. A total of 384 Cobb-500 broiler chicks were allocated to 4 nitrogen-free diets, each with 8 replicate cages and 12 birds per replicate. The diets were arranged as a 2 × 2 factorial with factors being dietary TI (0 or 8,000 TIU/g) and exogenous protease (0 or 15,000 PROT/kg). Desired dietary TI concentration was achieved by addition of commercially available, purified soybean TI. There was no effect of TI or exogenous protease or their interaction on growth performance of birds. However, the endogenous loss of nitrogen (N) and all AA increased (P < 0.05) due to dietary TI concentration except for Cys. The increase in endogenous AA due to TI ranged from 17% for Thr to 52.2% for Trp. Exogenous protease had no effect on endogenous loss of N and all AA. There was no effect of TI or exogenous protease or their interaction on the AID of P, however AID of Ca, Fe, Mg, Mn, and Cu was reduced (P < 0.05) due to dietary TI. The AID of Cu (P < 0.01) and K (P < 0.05) improved with exogenous protease supplementation. Significant interactions (P < 0.05) between exogenous protease and TI existed for Zn, Mg, Cu, and Na. The concentration (g/kg DM intake) of crude mucin and sialic acid increased (P < 0.05) with increased dietary TI. Decreased trypsin (P < 0.001) and increased chymotrypsin (P < 0.001) activity in the pancreas were observed as a result of exogenous protease supplementation. In conclusion, the current study showed that TI increases the endogenous loss of AA and reduced the digestibility of minerals in broiler chickens. Furthermore, exogenous protease did not affect endogenous AA flow, irrespective of added purified dietary TI.

Comparative digestibility and retention of calcium and phosphorus in normal- and high-phytate diets fed to gestating sows and growing pigs

The objective of this research was to test the hypothesis that calculated values for standardized total tract digestibility (STTD) and retention of Ca and P are not different between gestating sows and growing pigs. A total of 32 gestating sows (day of gestation = 40) and 32 castrates (body weight = 19.8 kg) were placed in metabolism crates. Two diets were formulated to contain 9.8 or 29.4 g/kg phytate. Diets were formulated based on corn, soybean meal, Ca carbonate, and dicalcium phosphate and the high-phytate diet also contained 400 g/kg full-fat rice bran. A Ca-free diet and a P-free diet were used to determine basal endogenous losses of Ca and P. Feces and urine were collected for 4 days after 4 days of adaptation. Results indicated that basal endogenous losses of Ca and P from gestating sows were greater (P < 0.05) than from growing pigs. The digestibility of dry matter was not affected by the physiological state of the animals, but was greater (P < 0.001) in the normal-phytate diet than in the high-phytate diet. Phytate level did not affect the STTD of Ca or Ca retention by gestating sows, but the STTD of Ca and Ca retention were greater if growing pigs were fed the normal-phytate diet than if they were fed the high-phytate diet (physiological state × phytate level interaction; P < 0.001). The STTD of P was greater for the normal-phytate diet than for the high-phytate diet, but the difference was greater for growing pigs than for gestating sows (physiological state × phytate level interaction; P = 0.002). Phosphorus retention by growing pigs fed the normal-phytate diet was greater than if they were fed the high-phytate diet, but P retention by gestating sows was not affected by phytate level (physiological state × phytate level interaction; P < 0.001). Regardless of phytate level, gestating sows had reduced (P < 0.001) STTD of Ca and P and reduced retention of Ca and P compared with growing pigs. In conclusion, gestating sows have reduced digestibility and retention of Ca and P, but increased basal endogenous losses of Ca and P, compared with growing pigs. Response to dietary phytate is different for STTD and retention of Ca and P between gestating sows and growing pigs. It may, therefore, not always be accurate to formulate diets for gestating sows using digestibility values for Ca and P that were obtained in growing pigs.

Egfl6 expression in the pharyngeal pouch is dispensable for craniofacial development

ABSTRACT Epidermal growth factor-like domain multiple 6 (Egfl6) is a basement membrane protein and plays an important role in hair follicle morphogenesis, angiogenesis, notochord development in vertebrates. Although egfl6 expression in the developing head was observed in zebrafish, its role for craniofacial development and the determination of the pharyngeal region expressing egfl6, have not been reported yet. Here, we report the expression patterns and function of egfl6 in craniofacial development in zebrafish. egfl6 was expressed sequentially in the developing pharyngeal pouches that are key epithelial structures governing the development of the vertebrate head. However, loss-of-function mutations in egfl6 did not cause any craniofacial defects, including the pouches as well as the thymus and facial cartilages whose development is contingent upon appropriate pouch formation. egfl6 was unlikely redundant with egfl7 expressed in a distinct pharyngeal region from that of egfl6 in craniofacial development because reduction of egfl7 with a MO in egfl6 mutants did not affect craniofacial development. In addition, we found that egfl6 carried an endogenous start loss mutation in the wild-type Tübingen strain, implying egfl6 would be a non-functional gene. Taken all together, we suggest that egfl6 expression in the pharyngeal pouches is not required for craniofacial development in zebrafish.

Evaluating endogenous loss and standard ileal digestibility of amino acids in response to the graded severity levels of E. maxima infection

The study was conducted to evaluate the effects of graded levels of Eimeria maxima challenge on endogenous loss, apparent ileal digestibility (AID), and standard ileal digestibility (SID) of amino acids. A total of 768 fourteen-day-old male Cobb 500 broiler chickens were randomly allocated into 64 battery cages. Apart from the regular corn-soybean based diet, the nitrogen-free diet (NFD) was formulated to determine the endogenous loss of amino acids. One-half of the birds (32 cages) were fed the NFD, and another half fed the regular diet from d 14 to 20. Both groups were further assigned to 4 treatments (nonchallenged control or three levels of challenge doses) with 8 replicate cages. The challenge doses were: the low challenge dose (Low) with E. maxima 12,500 oocysts, the medium challenge dose (Medium) with 25,000 E. maxima oocysts, and the high challenge dose (High) with 50,000 E. maxima oocysts. At 6 d postinfection, ileal digesta samples were collected and the intestinal lesion score were recorded. The results indicated a significant linear increase of endogenous amino acid flow in response to the graded E. maxima challenge. Moreover, the AID and SID of amino acids were linearly reduced due to the increasing challenge dose. The study demonstrated that NFD significantly reduced lesion scores, underestimating the true endogenous losses of birds fed regular diets. Even though the endogenous loss of amino acids was underestimated, they were linearly increased in response to the graded E. maxima challenge. In conclusion, the higher Eimeria dose birds were challenged with, the more endogenous amino acids were released into the intestine and the lower dietary nutrients were digested and absorbed by broiler chickens.

Meta-analysis-based estimates of efficiency of calcium utilisation by ruminants

The most abundant mineral in the body of animals is Ca, which has crucial importance for the regulation of various processes. The maintenance of Ca balance has become more challenging, especially in lactating ruminants, owing to the increased milk yields and thus Ca requirement. To determine the Ca requirement, factors such as Ca secretion via milk or Ca deposition in body tissues and conception products are summed up to the net Ca requirement. Nevertheless, dietary Ca cannot be completely utilised by the animal to cover the net Ca requirement, therefore a value for the efficiency of Ca utilisation is applied, which is the maximum proportion of Ca from the feed that the animal can use for covering the net requirement. However, current estimates for the efficiency of Ca utilisation are inconsistent. Therefore, the objective of the present meta-analysis was to estimate the efficiency of Ca utilisation for ruminants, considering the Ca supply of the animal. A data set of 223 observations was compiled from 37 studies, including data on cattle and small ruminants. Standardised Ca digestibility was calculated from data on Ca intake and faecal Ca excretion, corrected for faecal endogenous losses. Furthermore, a data subset on only lactating ruminants was created. For this subset, Ca excretion via faeces and urine and standardised Ca digestibility were related to the Ca supply of the animal. An exponential function was fitted to standardised digestibility data in response to Ca concentration in the diet and Ca supply, revealing that standardised Ca digestibility decreased with increasing dietary Ca concentration and Ca supply. The median for standardised Ca digestibility was 40%, with a remarkable variation between 9% and 88%. In response to Ca supply, faecal Ca excretion increased in a strong linear manner (slope = 0.76, R2 = 0.96). Excretion of Ca via urine was very low even when Ca supply was very high. To conclude, Ca digestibility is a suitable indicator for the efficiency of Ca utilisation, since excessive Ca is almost completely excreted in faeces; however, Ca digestibility has to be determined at a Ca supply level below the requirement of the animal. To date, only very limited number of data have been reported for such supply conditions. Comparative studies using various Ca sources are suggested for future studies but should be conducted using a marginal Ca supply level.

PSII-23 Addition of Hydrogen Chloride to Collection Bags or Containers Did Not Change Basal Endogenous Losses or Digestibility of Amino Acid in Corn, Soybean Meal, or Wheat Middlings Fed to Growing Pigs

Abstract The hypothesis that apparent ileal digestibility (AID), basal endogenous losses, and standardized ileal digestibility (SID) of AA are not affected by adding acid to collection containers or bags used to collect ileal digesta from pigs was tested. Twenty-four barrows (initial BW: 77.8 kg) that had a T-cannula installed in the distal ileum were fed diets for three 7-d periods. Corn, soybean meal, and wheat middlings were the sole AA sources in each diet and an N-free diet was also used. Within each period, each of the 4 diets was fed to 6 pigs. Among the 6 pigs, digesta from 3 pigs were collected in bags containing no HCl, whereas 40 mL of 3N HCl was included in the bags used to collect digesta from the remaining 3 pigs. Every other bag collected from each pig was emptied into a container without adding HCl, whereas the remaining bags were added to a container along with 40 mL of 3N HCl for each bag. All digesta were stored at –20 °C immediately after collection. Data were first analyzed using a model that included feed ingredient, HCl in bags, HCl in containers, and all 2-way and 3-way interactions as fixed effects. No 3-way interactions were significant, and data were, therefore, analyzed independently for each diet as a 2 × 2 factorial. Results indicated that there were no interactions between adding HCl to collection bags and to containers, and no effects of adding HCl to collection bags or containers for AID, basal endogenous losses, or SID of most AA were observed (Table 1). In conclusion, if digesta are stored at –20 °C immediately after collection, it is not necessary to add acid to digesta collection bags or collection containers.

141 Relationship Between Dietary Fiber and Basal Ileal Endogenous Losses of Amino Acids in Growing Pigs

Abstract Two experiments were conducted to determine the influence of sources or concentrations of dietary fiber in nitrogen-free diets (NFD) on basal ileal endogenous losses (BEL) of amino acids (AA) and subsequent standardized ileal digestibility (SID) of AA in feed ingredients for pigs derived from such BEL. In Exp. 1, 20 pigs (initial body weight = 46.5 ± 2.97 kg) were assigned to five diets in a quadruplicate 5 × 2 incomplete Latin square design with two periods. Three NFD containing cellulose (insoluble and fermentable fiber), inulin (soluble and fermentable fiber), or carboxymethyl cellulose (CMC; soluble and non-fermentable fiber) at 40 g/kg plus two diets containing soybean meal (SBM) or wheat distillers’ dried grains (WDDG) as the sole source of nitrogen were prepared. Pigs fed NFD containing CMC had greater (P &amp;lt; 0.05) BEL of AA, except for Arg and Pro, than those fed the other NFD. The SID of most AA in SBM and WDDG corrected by BEL of AA from NFD containing CMC were greater (P &amp;lt; 0.05) than those corrected by BEL of AA from the other NFD. Experiment 2 was conducted with 21 barrows (initial body weight = 34.1 ± 2.57 kg) assigned to seven diets in a triplicate 7 × 3 incomplete Latin square design with 3 periods. Seven diets consisted of three NFD containing 4, 8, or 12 g/kg cellulose and four diets containing corn, wheat, SBM, or canola meal as the sole source of nitrogen. There was no difference in the BEL of AA, except for Pro, among pigs fed NFD with increasing concentration of cellulose. The SID of AA in test ingredients were not affected by BEL of AA from NFD containing increasing concentration of cellulose. In conclusion, chemical characteristics of dietary fiber, but not concentration, affect the BEL of AA in pigs.

Manganese metabolism in the body of lactating fat-tailed ewes and the rate of need for it

We studied the exchange of manganese in the body of lactating ewes of the Kalmyk breed. It was found out that during lactation, the intensity of metabolism of this element in the body of ewes of the meat-feeding direction of productivity significantly increases. The factorial method, taking into account endogenous losses, determined the daily requirement of fat-tailed ewes in manganese.

Effect of xylanase supplementation on nutrient and energy digestibility at three time periods in growing pigs fed diets based on corn or corn distillers dried grains with solubles

A digestibility trial was conducted to better understand how xylanase impacts diet utilization in pigs by measuring its impact on the digestibility of energy, nitrogen, fat, fiber, and starch in the small and large intestine and across the total tract at three collection periods. Thirty-two 16-week-old gilts (DNA 600 [DNA Genetics, Columbus, NE, USA] × C22 [PIC Inc., Hendersonville, TN, USA]) were surgically fitted with T-cannulae at the terminal ileum, housed individually, and assigned to 1 of 4 dietary treatments in a completely randomized design, providing 24 observations per treatment Diets were arranged in a 2 × 2 factorial:0 vs 165 mg xylanase/kg (27,225 birch xylan units (BXU)/kg) of finished feed to corn-soybean meal diets and 0 g/kg (lower fiber: LF) vs 300 g/kg (higher fiber: HF) corn distillers’ dried grains with solubles (DDGS). Prior to surgery, the body weight (BW) of the pigs averaged 37.3 ± 0.8 kg. Three collection periods consisting of a 2-day fecal collection followed by a 3-day ileal collection occurred at day 9–13, 19–23 and 39–43 when pigs averaged 46.0 ± 0.4, 54.1 ± 0.4, and 70.3 ± 0.5 kg, respectively. Ileal and fecal samples were analyzed to determine the apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of gross energy (GE), dry matter (DM), neutral detergent fiber assayed with heat stable amylase (aNDF), acid detergent fiber (ADF), and nitrogen (N), and the AID of starch and amino acids (AA). Apparent fat digestibility values were corrected for endogenous losses and reported as true ileal digestibility (TID) and true total tract digestibility (TTTD). Xylanase inclusion tended to decrease AID of aNDF and decreased ADF in LF diets, but had no impact in HF diets, resulting in a fiber level (FL) × xylanase interaction (P ≤ 0.100). The AID of nitrogen increased with xylanase in LF diets, but decreased in HF diets, resulting in a FL × xylanase interaction (P = 0.025). Xylanase inclusion tended to increase the hindgut disappearance of aNDF and ADF (P ≤ 0.100). In LF diets, xylanase decreased ATTD of ADF, but increased ATTD of ADF in HF diets resulting in a FL × xylanase interaction (P = 0.010). Xylanase inclusion changed the pattern of hindgut disappearance and ATTD of nitrogen over the three collection periods, resulting in a xylanase × collection period interaction. Overall, xylanase supplementation slightly increased digestibility in pigs fed lower fiber diets, and had no impact on digestibility in higher fiber diets.

Estimation of endogenous intestinal losses of acid hydrolyzed ether extract in growing and finishing pigs using the linear regression method.

The approach of this experiment was to apply the regression method for the estimation of endogenous intestinal losses of ether extract (EEE) when pigs are fed complete diets ad libitum and using dietary levels of fat typical of those employed in commercial situations. A total of 40 gilts (PIC 337 sires × C22 or C29) were allotted to individual pens and randomly assigned to diets (8 pigs per treatment) with 5 different levels of acid hydrolyzed ether extract (AEE). The dietary treatments consisted of a corn-soybean meal diet with no added fat (L1); a corn-soy diet with 6% each of corn distiller’s dried grains with solubles (DDGS), corn germ meal, and wheat middlings (L2); the L2 diet but with 12% each of corn DDGS, corn germ meal, and wheat middlings (L3); the L2 diet plus soybean oil to equalize the NE concentration of the L2 diet with L1 (L4); and the L3 diet plus soybean oil to equalize the NE concentration of the L3 diet with L1 (L5). Pigs received feed and water ad libitum for the growing period (initial BW = 38.5 ± 1.2 kg) and the finishing period (initial BW = 73.82 ± 2.9 kg). A quadratic broken-line model was employed to estimate the response of apparent total tract digestibility (ATTD) of AEE to dietary AEE level. The average true total tract digestibility (TTTD) of AEE and endogenous losses of AEE were estimated using regression analysis of dietary AEE intake (g/kg of DM) against apparent digested AEE (g/kg of DMI). The ATTD of AEE increased in curvilinear fashion as dietary AEE level increased in growing and in finishing pigs (P < 0.001). This suggests an influence of EEE on the ATTD of AEE estimates. The linear regression of apparent digested AEE against dietary AEE intake (L1–L5; P < 0.001, R2 = 0.99 for growing pigs and P < 0.001, R2 = 0.99 for finishing pigs) estimated greater EEE (P < 0.05) and TTTD of AEE (P < 0.05) for growing than finishing pigs. Estimated EEE from growing pigs ranged between 18.1 and 20.2 g/kg of DMI, while TTTD of AEE ranged between 96.40% and 100.70%. In finishing pigs, EEE ranged between 21.6 and 23.8 g/kg of DMI and TTTD of AEE ranged between 91.30% and 95.25%. In conclusion, EEE under practical conditions is estimated to be 19.2 g/kg of DMI in growing and 22.7 g/kg of DMI in finishing pigs.

Amino acid digestibility in diets containing copra meal with β-mannanase fed to growing pigs.

ObjectiveThe objective of this study was to estimate standardized ileal digestibility (SID) of amino acids (AA) in growing pigs fed diets containing increasing levels of copra meal (CM) with β-mannanase supplementation.MethodsTwenty barrows (initial body weight: 34.43±0.11 kg) surgically fitted with T-cannulas at the distal ileum were individually housed in metabolism crates. Pigs were allotted to 5 dietary treatments in a completely randomized design with 4 replicates per treatment. The dietary treatments were: i) NC, negative control, corn-soybean meal (SBM) based diet, ii) PC, positive control, basal diet + 0.10% β-mannanase supplementation (800 IU/kg), iii) CM6, PC diet with 6% CM supplementation, iv) CM12, PC diet with 12% CM supplementation, and v) CM18, PC diet with 18% CM supplementation. A nitrogen-free diet was used to estimate basal endogenous losses of AA for SID calculation. All experimental diets contained 0.5% chromic oxide as an indigestible marker. Each period consisted of a 4-d diet adaptation period and a 3-d ileal digesta collection period.ResultsThere were no differences in apparent ileal digestibility (AID) and SID of all AA between the NC and PC treatments except that the PC treatment had lower AID and SID of glycine than the NC treatment (p<0.05). There were linear decreases in AID and SID of lysine (p<0.05) and aspartic acid (p = 0.06; tendency) with increasing levels of CM in the diets with β-mannanase.ConclusionThe β-mannanase supplementation had no effect on AA digestibility in pigs fed the corn-SBM based diet but increasing levels of CM reduced SID of lysine and aspartic acid.

Addition of hydrochloric acid to collection bags or collection containers did not change basal endogenous losses or ileal digestibility of amino acid in corn, soybean meal, or wheat middlings fed to growing pigs.

ObjectiveThe hypothesis was that apparent ileal digestibility (AID), basal endogenous losses, and standardized ileal digestibility (SID) of amino acids (AA) are not affected by adding acid to collection containers or bags used to collect ileal digesta from pigs.MethodsTwenty-four growing barrows (initial body weight: 77.8±4.5 kg) that were fitted with a T-cannula in the distal ileum were fed diets for three 7-d periods. An N-free diet and 3 diets containing corn, soybean meal, or wheat middlings as the sole source of AA were used. Within each period, each of the 4 diets were fed to 6 pigs. Among the 6 pigs, digesta from 3 pigs were collected in bags containing no HCl, whereas 40 mL of 3 N HCl was included in the bags used to collect digesta from the remaining 3 pigs. Every other bag collected from each pig was emptied into a container without adding HCl, whereas the remaining bags were added to a container along with 40 mL of 3 N HCl for each bag. All digesta were stored at −20°C immediately after collection. Data were analyzed using a model that included feed ingredient, HCl in bags, HCl in containers, and all 2-way and 3-way interactions as fixed effects. No 3-way interactions were significant, and data were, therefore, reanalyzed independently for each diet as a 2×2 factorial.ResultsThere were no interactions between adding HCl to collection bags and to containers, and no effects of adding HCl to collection bags or containers for AID, basal endogenous losses, or SID of most AA were observed.ConclusionIt is not necessary to add acid to digesta collection bags or collection containers if ileal digesta are stored at −20°C immediately after collection.

Nutrient digestibility of heat-processed field pea in weaned pigs

Field pea grain can be included in growing-finishing pig diets as an alternative starch and protein source without affecting growth performance. However, for weaned pigs, there is a concern to include field pea grain in diets because of lower energy digestibility compared with soybean meal and corn grain and the presence of trypsin inhibitors that may affect protein digestion. Processing using heat and friction may reduce trypsin inhibitor activity in field pea grain and increase both energy and protein digestibility; however, its effect on weaned pigs remains unknown. To explore, field pea grain was cold-pelleted (70–75 °C), steam-pelleted (80–85 °C) or single-screw extruded (115 °C). The raw and 3 processed field pea grain samples were included in 4 test diets at 956 g/kg and fed to 8 ileal-cannulated weaned barrows (initial body weight, 11.6 ± 1.2 kg) in a double 4 × 4 Latin square. A N-free diet was also fed to pigs to measure basal endogenous losses of amino acids. Cold-pelleting and extrusion reduced trypsin inhibitor activity (TIA) by 0.8–1.1 mg/g in field pea grain. Cold-pelleting increased (P < 0.05) the coefficient of apparent total tract digestibility of dry matter and gross energy, but not crude protein of field pea grain. Cold-pelleting increased (P < 0.05) digestible energy and calculated net energy values of field pea grain, and the coefficient of apparent ileal digestibility of dry matter, gross energy and starch. Extrusion increased (P < 0.05) the coefficient of standardised ileal digestibility of threonine, tryptophan, valine, serine and tyrosine of field pea grain. In conclusion, cold-pelleting reduced TIA and increased the energy value of field pea grain, and extrusion reduced TIA and increased ileal digestibility of some amino acids compared with raw field pea grain fed to weaned pigs.

Energy and amino acid digestibility of raw, steam-pelleted and extruded red lentil in growing pigs

Lentil is an alternative feedstuff providing both starch and protein with a lower energy and amino acid (AA) digestibility in pigs than conventional feedstuffs. However, heat processing may increase the digestibility of energy and AA and thereby increase the nutritive value of lentil. Therefore, a study was conducted to test effects of steam-pelleting and extrusion of lentil on digestible energy (DE) and calculated net energy (NE) values and AA digestibility in growing pigs. Three diets containing 956 g/kg of either raw, steam-pelleted (80–85 °C) or extruded (115 °C) lentil were fed to 9 ileal-cannulated growing pigs (initial body weight = 69.0 ± 6.7 kg) at 2.8 × maintenance DE in a triplicate 3 × 3 Latin square with 3 periods. An N-free diet was fed to all pigs to measure basal endogenous losses of AA at the start of the trial. Each 9-day period comprised sequentially of a 5-day adaptation, 2-day faecal collection and 2-day ileal digesta collection. Steam-pelleting and extrusion increased (P < 0.05) the coefficient of apparent total tract digestibility (CATTD) of dry matter (DM), gross energy (GE) and crude protein (CP) of lentil, and increased (P < 0.05) the calculated NE values of lentil grain. Steam-pelleting or extrusion increased (P < 0.05) the coefficients of standardised ileal digestibility (CSID) of CP and AA. In conclusion, heat processing can increase the digestibility of AA and the energy value of lentil in growing pigs that may increase the use of lentil as alternative feedstuff for pigs. Among heat processing methods, steam pelleting would be sufficient to achieve increased DE and calculated NE values and CSID of AA of lentil.

Copper hydroxychloride improves gain to feed ratio in pigs, but this is not due to improved true total tract digestibility of acid hydrolyzed ether extract

Two experiments were conducted to test the hypothesis that copper (Cu) from Cu hydroxychloride improves gain to feed ratio (G:F) when fed to pigs by increasing apparent total tract digestibility (ATTD) of fat. In experiment 1, 144 pigs (15.40 ± 2.39 kg) were allotted to 6 treatments with 2 pigs per pen and 12 replicate pens per diet. Pigs were fed diets with increasing concentrations of extracted fat by adding 20, 40, or 60 g/kg choice white grease (CWG) to a diet based on corn, soybean meal (SBM), and distillers dried grains with solubles (DDGS), which contained no CWG. Two additional diets were formulated by adding 150 mg/kg of Cu from Cu hydroxychloride to the diet without added CWG and to the diet with 20 g/kg added CWG. Diets were fed for 4 weeks. Results indicated that supplementation of diets with either CWG or Cu hydroxychloride improved (P < 0.05) G:F of pigs, and the improvement obtained by Cu hydroxychloride supplementation was similar to the improvement in G:F obtained by adding 28–38 g/kg CWG to the diets. In experiment 2, 64 pigs (18.22 ± 1.80 kg) were housed individually in metabolism crates and randomly allotted to 8 diets with 8 replicate pigs per diet. Two basal diets based on corn, SBM, corn bran, cornstarch, and casein were formulated. The only difference between the 2 diets was that one diet contained no Cu hydroxychloride, whereas the other diet contained 150 mg/kg of Cu from Cu hydroxychloride. Six additional diets were formulated by adding 150, 300, or 450 g/kg DDGS to both basal diets at the expense of cornstarch and corn bran. Feces were collected using the marker-to-marker approach with 5-day adaptation and 4-day collection periods. Supplementation of Cu hydroxychloride to diets improved (P < 0.05) the ATTD of acid hydrolyzed ether extract (AEE), but did not affect ATTD of dry matter or gross energy (GE). Supplementation of Cu hydroxychloride to diets also reduced (P < 0.05) total tract endogenous loss of fat, but did not affect true total tract digestibility of AEE. This indicates that the increased G:F of pigs that was observed in experiment 1 as a result of Cu supplementation to diets was not due to improved ATTD of GE, but may be a result of Cu influencing post absorptive lipid metabolism. In conclusion, supplementation of Cu from Cu hydroxychloride to diets improved G:F in pigs, which may be due to effects of Cu on post-absorptive metabolism of energy and fat.

Endogenous Losses of Nitrogen and Protein Requirement for Maintenance of Sheep

FOUR fistulated and four intact West African dwarf Sheep, maintained on hay and concentrate supplements were used for a study of metabolic faecal nitrogen (MEN) endogenous urinary nitrogen (EUN). The composition of the faecal losses was examined. The values obtained enabled calculation of nitrogen requirement of the sheep for maintenance, as well as the value of the experimental rations in the nutrition of the sheep. Values of MFN obtained by two methods were 3.31 and 3.10 g/kg Dry matter (DM) intake. Endogenous urinary nitrogen value was 0.024 g/day per metabolic weight (Wkg0.75.) Analysis of the faeces of the sheep showed that 21.1% of faecal nitrogen (N) were present as microbial and endogenous nitrogen (MEN) and 17.3% was present as water-soluble nitrogen. The biological values (BV) of the rations ranged from 85.7% to 100.0% and the digestibility for maintenance, were 1.20 and 0.41 g/day/Wkg 0.75 during the feeding trials. Values obtained for endogenous N losses and N requirement for low maintenance were low compared with reported values and this may indicate adaptation of the dwarf sheep for survival under inadequate dietary protein supply.