Biomedical subjects

G C Fahey

Publications and source records attributed to G C Fahey.

At least 37 records · Page 2Linked to original sources

PubMed2002

Regional and processor variation in the ileal digestible amino acid content of soybean meals measured in growing swine.

To assess differences in soybean meal quality related to region of production, researchers in Illinois, Kansas, North Carolina, The Netherlands, and Ohio collected four soybean meal samples processed locally at least 15 d apart. These samples were assayed for ileal amino acid digestibility by pigs using a common soybean meal and a soy protein concentrate as references, and a low-protein casein diet for determination of endogenous amino acid losses. Digestibility was determined at each university using seven barrows surgically fitted with ileal cannulas in a 7 x 7 Latin square design. The experimental diets contained 17% CP from the test material except for the low-protein casein diet. Animals were fed twice daily, 12 h apart, at a level of 45 g x kg(-0.75) BW for each meal. Following a 5-d adaptation period, ileal digesta were collected for two 12-h periods for 2 d to be used for determination of ileal digestibility. Variation in amino acid digestibility was very small among and within sites and was much smaller than variation in the concentration of amino acids. Among sites, samples from The Netherlands had less total and thus digestible lysine and methionine than the U.S. samples (P < 0.05). The soybean meals tested in this experiment were approximately 4% higher in amino acids than that reported in the NRC (1998). True (standardized) digestibilities, however, were very similar to NRC values except for cysteine and threonine, which were 5 and 3 percentage points lower in this experiment, respectively. In conclusion, soybeans grown in the United States and locally processed into soybean meal were very similar in nutritional composition. Soybean meals produced in The Netherlands were lower in lysine and methionine (P < 0.05) but had a digestibility similar to that produced in the United States.

Amino Acids↗

PubMed2002

The influence of soy oligosaccharides on apparent and true ileal amino acid digestibilities and fecal consistency in growing pigs.

Fourteen ileally cannulated pigs (BW = 35 +/- 2 kg) were randomly allotted to a replicated 7 x 7 Latin square design experiment to evaluate the influence of the soybean oligosaccharides (OS), raffinose and stachyose, on ileal nutrient digestibility and fecal consistency. Semipurified diets containing soy protein concentrate (SPC) or soybean meal (SBM) as the sole protein sources were fed. Soy solubles (SS), a by-product of SBM processing containing 3.5% raffinose and 11.5% stachyose, were used to increase dietary raffinose and stachyose concentrations. The seven dietary treatments were SPC, SPC + 9% SS, SBM, SBM + 9% SS, SBM + 18% SS, SBM + 24,000 U alpha-galactosidase enzyme preparation/kg diet, and a low-protein casein (LPC) diet used to calculate true digestibility. Diets, with the exception of the LPC diet, were formulated to contain 17% CP. All diets contained 0.5% chromic oxide as a marker for ileal digestibility determination. The experimental periods were divided into a 5-d diet adaptation followed by 2-d of ileal digesta collection. Diets and digesta were analyzed for DM, N, Cr, amino acids (AA), raffinose, and stachyose. Fecal consistency was determined on d 6 and 7 of each experimental period. The apparent and true ileal AA digestibilities were not different (P < 0.05) for the SPC and SBM control diets. When SS was added to the SPC diet, apparent and true N and AA digestibilities were depressed (P < 0.05) with the exception of Trp and Pro. The apparent and true ileal N and AA digestibilities were not different (P > 0.05) between the SBM control and SBM + 9% SS diets with the exception of Glu. There was a linear decrease (P < 0.05) in apparent and true DM, Val, Gly, and Tyr digestibilities when increasing levels of SS were added to the SBM diet. The addition of alpha-galactosidase did not improve apparent or true ileal N or AA digestibilities except for apparent and true Val and Tyr. Ileal raffinose digestibility was improved (P < 0.05) by addition of a-galactosidase, but was not affected by any other dietary treatment. Ileal stachyose digestibility was not affected (P > 0.58) by treatment. Fecal consistency likewise was not affected (P > 0.36) by dietary treatment. In conclusion, soy OS reduced nutrient digestibilities, but the reductions were small, ranging from approximately 1.1 to 7.4 percentage units. This suggests that other factors may be negatively impacting SBM digestibility.

Amino Acids↗

PubMed2001

Comparison of quality characteristics of soybeans from Brazil, China, and the United States.

Both soybean composition and processing conditions impact the nutritional quality of soybean meal. The objective of this experiment was to compare nutrient compositions of soybeans grown under diverse environmental conditions in a variety of locations. Dry matter, organic matter, and ash concentrations differed in soybeans collected within the countries of Brazil, China, and the United States, although these differences were generally small or due to uniqueness of a particular source. Large differences in dry matter were detected among countries. Differences in crude protein, amino acid, and lipid concentrations of soybeans were detected both within and among countries. Soybeans from China had a greater crude protein concentration (42.14%) than those from Brazil (40.86%), whereas soybeans from China had a lower lipid concentration (17.25%) than those from either Brazil or the United States (18.66 and 18.70%, respectively). Environmental conditions under which soybeans are grown have a great impact on chemical composition and nutrient quality.

Brazil↗

PubMed2001

Starch and fiber fractions in selected food and feed ingredients affect their small intestinal digestibility and fermentability and their large bowel fermentability in vitro in a canine model.

The digestion of legumes, cereal grains, cereal and potato flours and grain-based foods in dogs was studied using two in vitro model systems. The first simulated the stomach and small intestine through the additions of acid and enzymes and large bowel fermentation through use of fecal inocula from dogs, and the second simulated small intestinal fermentation using canine ileal chyme as the bacterial source. All substrates were analyzed for total dietary fiber (TDF) including insoluble and soluble components, and starch fractions: rapidly digestible starch, slowly digestible starch, resistant starch (RS) and total starch. Legumes had high TDF and RS concentrations (mean 36.5 and 24.7%, respectively), resulting in lower ileal digestible starch and total digestible starch concentrations (mean 21 and 31%, respectively). Seventy-four percent of the TS in the cereal grains group was rapidly digestible starch plus slowly digestible starch compared with the flour group, where the corresponding value was 95%. This related to the processing of cereals to flours, in which TDF and RS concentrations were reduced markedly. This increased ileal digestible starch concentrations in the flour group (65%) versus the cereal grains group (60%). Ileal digestion of starch in grain-based food products like macaroni and spaghetti was high (96 and 92%, expressed as a percentage of TS, respectively). Fermentation of substrates with ileal microflora was influenced by substrate chemical composition, with the flour group exhibiting the highest organic matter disappearance values. The legume group had a high total short-chain fatty acid concentration (7.8 mmol/g organic matter fermented), perhaps as a result of fermentation of TDF as well as starch components. A database such as this one provides information about utilization of foods and feeds in the dog and potentially in humans.

Animals↗

PubMed2001

The ratio of insoluble to soluble fiber components in soybean hulls affects ileal and total-tract nutrient digestibilities and fecal characteristics of dogs.

An experiment was conducted to evaluate the effects of soybean hulls (SH) containing varying ratios of insoluble:soluble fiber (I:S) on nutrient digestibilities and fecal characteristics of dogs. Ileally cannulated dogs (n = 6) were fed seven diets in a 6 x 7 Youden square arrangement of treatments. The seven diets included five SH-containing diets with I:S of 1.9, 2.7, 3.2, 5.2 or 7.2 and two diets containing either beet pulp (BP) or no supplemental fiber (control). Ileal digestibilities of DM, OM, CP, total dietary fiber (TDF), fat and gross energy (GE) were lower (P < 0.05) for dogs fed diets containing supplemental fiber compared with dogs fed the control diet. Fiber inclusion had a modest negative effect (P < 0.05) on total-tract DM, OM, fat and GE digestibilities compared with the control diet. Ileal digestibilities of DM and OM by dogs fed the SH treatments responded quadratically (P < 0.05) to I:S, with digestibility coefficients decreasing as the I:S approached 3.2. Highest ileal digestibilities were observed for diets with an I:S of 1.9 and 7.2. Similarly, a quadratic response (P < 0.05) was observed for digestibility of total amino acids at the ileum. Fecal outputs were lower (P < 0.001) when dogs consumed the control diet vs. fiber-containing diets. Among the SH-containing diets, there was a linear increase in fecal output as I:S increased (P = 0.031). The I:S in the diet affects DM and OM digestibilities at the ileum and affects fecal output, indicating that optimization of this ratio is desirable.

Amino Acids↗

PubMed2001

Dietary fat supplementation effects on in vitro nutrient disappearance and in vivo nutrient intake and total tract digestibility by horses.

Addition of fat to the diet of the equine is a popular method of increasing energy density of the diet while reducing feed intake. Reducing feed intake is of interest to race horse trainers because additional feed is seen as additional weight and, therefore, a hindrance to performance. Limited information is available regarding the interactions of fat with other dietary components, particularly fiber, in the equine digestive system. The effect of dietary fat on in vitro nutrient disappearance in equine cecal fluid was studied in Exp. 1 using a split-plot design within a 2 x 2 Latin square. Two ponies were fed alfalfa (ALF) alone or alfalfa plus 100 g/d corn oil. Five substrates were used to determine in vitro DM disappearance, OM disappearance, NDF disappearance, and total dietary fiber (TDF) disappearance. The substrates included: ALF, tall fescue (TF), red clover (RC), soybean hulls (SBH), and rolled oats (RO). Fat supplementation did not affect in vitro DM, OM, or NDF disappearance. Addition of fat to the diet increased (P < 0.05) the disappearance of NDF in RO. Among substrates, in vitro DM and OM disappearance were highest (P < 0.05) for RO, followed by SBH, ALF, RC, and TF. In vitro NDF and TDF disappearance were highest (P < 0.05) for SBH, followed by RO, ALF, RC, and TF. In Exp. 2, the effects of varying levels of fat on nutrient intake and total tract digestibility were examined using a 4 x 4 Latin square design. Four mature mares were fed a 60% forage-40% concentrate diet containing different concentrations of fat: 0% supplemental fat control (C); 5% supplemental corn oil (5% CO); 10% supplemental corn oil (10% CO); or 15% supplemental corn oil (15% CO). Treatment did not affect intake of the concentrate portion of the diet or CP, gross energy, or NDF intake. Mares consuming the C diet had the highest (P < 0.05) intake of alfalfa cubes, DM, and OM, followed by those on the 10, 5, and 15% CO treatments, respectively. Treatment did not affect nutrient digestibility. Mares consuming the 15% CO diet had the highest (P < 0.05) fat digestibility, whereas those consuming C had the lowest fat digestibility. Fat in the form of CO generally had little effect on in vitro and in vivo nutrient digestibilities in horses.

Animals↗

PubMed2001

In vitro fermentation characteristics of native and processed cereal grains and potato starch using ileal chyme from dogs.

Two in vitro experiments were conducted to evaluate the ability of small intestinal bacteria of dogs to ferment native and extruded cereal grains and potato starch and cereal grain and potato flours. Substrates included barley, corn, potato, rice, sorghum, and wheat. In addition to testing native grains and flours, extruded substrates also were tested. Substrates were extruded at low temperatures (LT; 79 to 93 degrees C) and high temperatures (HT; 124 to 140 degrees C) using a Wenger extruder (model TX-52). Substrates varied widely in concentrations of rapidly digestible starch (RDS), slowly digestible starch (SDS), resistant starch (RS), and total starch (TS). Extrusion of most substrates at HT vs LT resulted in increased RDS and decreased RS concentrations. Organic matter disappearance (OMD) values attributed to microbial fermentation for a 5-h period were as high as 27% for native extruded substrates (LT potato starch) and 39% for potato flour. Average OMD was higher for cereal and potato flours than for native extruded substrates (29.9 vs 25.4%). Average molar percentages of short-chain fatty acids produced from all substrates fermented for 5 h were 73, 14, and 13% (acetate, propionate, and butyrate, respectively). Average lactate production for substrates ranked as follows: flours > native and extruded cereal grains and potato starch (0.33 and 0.18 mmol/g OM, respectively). In vitro microbial fermentation of starches by ileal bacteria can be substantial and is affected by differences in starch source, fraction, and processed form.

Animals↗

PubMed2001

Fruit and vegetable fiber fermentation by gut microflora from canines.

The objective of this study was to assess fermentability by canine gut microflora to include shortchain fatty acid (SCFA) production, organic matter (OM) disappearance, and gas production of vegetable and fruit fiber sources compared to fiber standards (psyllium, citrus pectin, and Solka Floc). Fiber sources included apple pomace, carrot pomace, flaxseed, fruit blend (mixture of peach, almond, nectarine, and plum), grape pomace, pea hulls, pistachio, and tomato pomace. Substrates were fermented in vitro for 4, 12, and 24 h with fecal flora obtained from three healthy dogs. Citrus pectin had the highest OM disappearance, SCFA production, and gas production at all times of fermentation; psyllium was intermediate and Solka Floc was lowest. A wide variation in fermentability was noted among the vegetable and fruit fiber sources. Apple pomace, carrot pomace, and flaxseed had the greatest fermentability as assessed by OM disappearance. Pea hulls and tomato pomace had intermediate OM disappearances, and fruit blend, grape pomace, and pistachio were poorly fermented. Carrot pomace produced the largest amounts of gas and SCFA. Apple pomace produced high concentrations of gas but intermediate concentrations of SCFA. Pea hulls and tomato pomace produced intermediate concentrations of gas and SCFA, whereas flaxseed, fruit blend, grape pomace, and pistachio produced low amounts of these fermentation products. For all substrates collectively, OM disappearance was highly correlated with both gas production (r2 = 0.782 and 0.723 for 12- and 24-h values, respectively) and SCFA production (r2 = 0.737 and 0.738 for 12- and 24-h values, respectively). In general, OM disappearance, gas production, and SCFA production were related to the insoluble:soluble fiber ratio in the samples; as the insoluble:soluble ratio decreased (increased soluble fiber), the OM disappearance, gas production, and SCFA production increased.

Animal Feed↗

PubMed2001

Ileal and total tract nutrient digestibilities and fecal characteristics of dogs as affected by soybean protein inclusion in dry, extruded diets.

Plant-based protein sources are generally less variable in chemical composition than animal-based protein sources. However, relatively few data are available on the nutrient digestibilities of plant-based protein sources by companion animals. The effects of including selected soybean protein sources in dog diets on nutrient digestion at the ileum and in the total tract, as well as on fecal characteristics, were evaluated. Six protein sources were used: soybean meal (SBM), Soyafluff 200W (soy flour), Profine F (traditional aqueous-alcohol extracted soy protein concentrate [SPC 1]), Profine E (extruded SPC [SPC 2]), Soyarich I (modified molecular weight SPC [SPC 3]), and poultry meal (PM). All diets were extruded and kibbled. Test ingredients varied in CP and fat contents; however, diets were formulated to be isonitrogenous and isocaloric. Nutrient intakes were similar, except for total dietary fiber (TDF), which was lower (P < 0.01) for dogs fed the PM diet. Apparent ileal digestibilities of DM, OM, fat, and TDF were not different among treatments; however, CP digestibility at the terminal ileum was higher (P < 0.01) for diets containing soy protein sources than for PM. Total tract CP digestibility was greater (P < 0.01) for soy protein-containing diets than for PM. Apparent total tract digestibilities of DM, OM, fat, and TDF were not different among treatments. Apparent amino acid digestibilities at the terminal ileum, excluding methionine, threonine, alanine, and glycine, were higher (P < 0.01) for soy protein-containing diets than for PM. Dogs fed SPC diets had lower (P < 0.01) fecal outputs (g asis feces/g DMI) than dogs fed the SF diet, and dogs fed SBM tended (P < 0.11) to have lower fecal outputs than dogs fed the SF diet. However, dogs fed the PM diet had lower (P < 0.03) fecal outputs than dogs fed SPC-containing diets. Fecal outputs and scores reflected the TDF and nonstructural carbohydrate contents of the soy protein fraction. Soy protein sources are well utilized by the dog prior to the terminal ileum, and SPC offers a viable alternative to PM as a protein source in dry, extruded canine diets.

Amino Acids↗

PubMed2000

Selected animal and plant protein sources affect nutrient digestibility and fecal characteristics of ileally cannulated dogs.

The objective of this study was to compare ileal and total tract nutrient digestibilities and fecal characteristics of dogs fed selected animal and plant protein sources incorporated into grain-based diets. Four crude protein sources--soybean meal (SBM), poultry meal (PM), poultry by-product meal (PBPM), and beef and bone meal (BBM)--were fed to four ileal cannulated dogs in a 4 x 4 Latin square design. Intakes of dry matter, organic matter, crude protein, and fat by dogs were similar. Total dietary fiber (TDF) intake was highest for the SBM treatment compared to other treatments. Ileal digestibilities of DM, OM, CP, fat, and TDF were not affected by treatment. Total tract digestibility of DM was lower for the BBM and SBM diets, while OM digestibility was lower for the SBM treatment only. Total tract CP digestibility was similar for BBM, PBPM, and SBM treatments and was higher for the PM treatment. As-is fecal excretion [g/d] was greater when dogs received the SBM treatment. Fecal output on a DM basis was higher for the SBM treatment compared to the other treatments. All diets were well utilized by the dogs as assessed by ileal and total tract digestibility data and fecal characteristics.

Amino Acids↗

PubMed2000

Glucose-based oligosaccharides exhibit different in vitro fermentation patterns and affect in vivo apparent nutrient digestibility and microbial populations in dogs.

To evaluate the potential of indigestible oligosaccharides (OS) to serve as "dietary fiber-like" ingredients, it is necessary to determine their extent of indigestibility. In vitro fermentation characteristics of two novel OS, alpha-glucooligosaccharides (GOS) and a maltodextrin-like OS (MD), were compared to those of fructooligosaccharides (FOS), gum arabic (GA), guar gum (GG) and guar hydrolysate (GH). Total short-chain fatty acid (SCFA) production (micromol/g dry matter) as a result of MD fermentation was higher initially compared with GA (P<0.01), but GA was more extensively fermented at 24 h (P<0.01). Total SCFA production for GOS was similar to that for FOS, GG, GH and GA. In the second experiment, GOS and MD were added at 6% to an enteral formula control diet (Control) and fed to ileal-cannulated dogs in a 3x3 replicated Latin-square design. Ileal digestibility of glucose was lower (P<0.05) and carbohydrate (CHO) numerically lower (P = 0.08) for both GOS and MD compared with the Control. Total tract digestibility of CHO and glucose was lower only for MD (P<0.01) compared with the Control. Total fecal weights were higher (P<0.01) for both GOS and MD treatments. Fecal concentration of bifidobacteria was numerically increased by GOS and MD supplementation (P = 0.13 and 0.23, respectively). Thus, GOS and MD are indigestible yet fermentable OS, and may act as "dietary fiber-like" ingredients.

Animals↗

PubMed1999

Apparent digestibility and glycaemic responses to an experimental induced viscosity dietary fibre incorporated into an enteral formula fed to dogs cannulated in the ileum.

The purpose of this study was to evaluate the apparent digestibility and postprandial glycaemic responses of ileal-cannulated dogs when fed an experimental induced viscosity dietary fibre (IVF) incorporated into a liquid enteral formula. Dietary treatments were: (1) control; (2) Glucerna; (3) Glytrol; (4) IVF; and (5) Jevity. Diets varied in concentrations of crude protein (CP), fat, starch and total dietary fibre (TDF). Dry matter and starch intakes by dogs fed the Glucerna and Glytrol treatments were lower (P<0.05) than for those consuming the other diets. However, daily intakes of CP and fat followed a reverse trend. Digestibility of nutrients at the ileum was high (>80%) for all dietary treatments. Mineral absorption proximal to the ileum and from the total tract was not significantly different among treatments. Mean incremental area under the serum glucose response curves for dogs fed Glytrol, Glucerna, and IVF treatments were lower (P<0.05) than the control treatment. Induced viscosity fibre appears to have no negative effects on nutrient digestion throughout the gastrointestinal tract. Its ability to moderate serum glucose concentrations would make it a potentially good choice for a diabetic liquid formula.

Animals↗

PubMed1999

Effects of chemical modification on in vitro rate and extent of food starch digestion: an attempt to discover a slowly digested starch.

Differences in glycemic and insulinemic responses to dietary starch are directly related to the rate of starch digestion. Chemical modification of starch may allow for the production of a slowly digested starch that could be used for the treatment of certain medical modalities. An in vitro method was utilized to evaluate the effects of chemical modification on the rate and extent of raw and cooked starch digestion. The extent of starch digestion was significantly reduced by dextrinization, etherification, and oxidation. However, the rate of starch digestion was not significantly affected by chemical modification. For most modified starches, as the degree of modification increased, the extent of digestion decreased, suggesting an increase in the amount of resistant starch. The results of this study suggest that chemically modified starch has a metabolizable energy value of <16.7 kJ/g. Chemically modified starch ingredients may serve as a good source of resistant starch in human and animal diets.

Animal Feed↗

PubMed1999

Petfood applications of inulin and oligofructose.

Published data on intestinal microbiota of dogs and cats are limited but suggest the presence of a complex and diverse colonic bacterial population (34 genera including 129 species) the majority of which are anaerobes. During the colonic fermentation of endogenous and undigested amino acids, several putrefactive compounds (i.e., ammonia, aliphatic amines, indoles, phenols and volatile sulfur-containing compounds) are produced and are responsible for the malodor of dog and cat feces. These fecal odor components also have been implicated as causes of colorectal cancer; therefore, dietary manipulation of gut microbiota towards a potentially more remedial community (Bifidobacterium and Lactobacillus) is gaining more attention. The health benefits derived from dietary supplementation of prebiotics (e.g., oligofructose and inulin) have been documented in humans. However, little is known of a potentially similar role in companion animals. Feeding another prebiotic (i.e., lactosucrose) to dogs or cats is reported to increase the numbers of bifidobacteria and decrease the numbers of pathogens and the concentration of fecal odor components. In our laboratory, oligofructose supplementation numerically decreased the concentrations of ammonia and amines and increased the numbers of bifidobacteria in dog feces.

Animal Feed↗

PubMed1999

Effects of a return chewing gum/packaging material mixture on in situ disappearance and on feed intake, nutrient digestibility, and ruminal characteristics of growing steers.

In situ and in vivo digestibility experiments were conducted to determine the acceptability, digestibility, and safety of a return chewing gum/packaging (G/P) material mixture when fed to steers. In the in situ experiment, both ruminal and intestinal disappearances were measured. Two ruminally and duodenally cannulated steers, which were given free access to alfalfa hay (AH), were used in this study. Duplicate Dacron bags containing the G/P were incubated in the rumen for 0, 3, 6, 12, 24, and 48 h. After ruminal incubation, the 12-, 24-, and 48-h bags were placed in the duodenum and collected in the feces to determine intestinal disappearance. In situ ruminal DM disappearance was greater than 70% for all substrates tested at 0 h, indicating high solubility of the substrates in water, and began to reach a plateau after 12 h of incubation. Intestinal in situ disappearance was not different (P>.25) from zero. In the digestion trial, four ruminally cannulated steers (337+/-21.3 kg BW; mean +/- SD) were used in a 4x4 Latin square design with the following treatments: 0) 50% corn (C), 50% AH; 10) 45% C, 45% AH, 10% G/P; 20) 40% C, 40% AH, 20% G/P; 30) 35% C, 35% AH, 30% G/P. Steers fed G/P-containing diets had greater (P<.01) DMI than the control steers. Increasing the G/P resulted in a linear (P<.05) increase in DMI. Apparent DM digestibility tended to be higher (P<.10) for the G/P-containing diets than for the control. A quadratic effect (P<.05) on digestible DMI was observed, with greater (P<.01) digestible DMI values for G/P-containing diets (4.8 vs. 5.8 kg/d). Digestible organic matter and total nonstructural carbohydrate intakes followed trends similar to those of DM. Apparent aluminum digestibility of G/P-containing diets was not different (P>.13) from zero. The level of G/P in the diet had no effect (P>.2) on total VFA concentration or ruminal pH. There was a linear decrease (P<.01) in the molar percentage of isobutyrate and isovalerate in addition to a linear increase (P<.01) in butyrate and valerate with increasing levels of G/P. There was a quadratic effect (P<.01) on molar proportions of acetate and propionate and on the acetate:propionate ratio. Results of both experiments suggest that G/P may be fed to safely replace up to 30% of corn-alfalfa hay diets for growing steers with advantages in improving DMI and digestibility.

Animals↗

PubMed1999

Soybean hulls as a dietary fiber source for dogs.

In Exp. 1, soybean hull samples were obtained from nine sources across the United States and analyzed for nutrient content to determine their suitability for inclusion in dog diets. Compositional data revealed variation in both the amount of total dietary fiber (TDF; 63.8 to 81.2%) in the soybean hulls and the ratio of insoluble:soluble fiber (5.0:1 to 15.4:1). Crude protein content varied widely among sources, ranging from 9.2 to 18.7%. An in vivo trial (Exp. 2) was conducted using a premium dog diet containing 3.0, 4.5, 6.0, 7.5, or 9.0% soybean hulls (DM basis). There was a negative linear effect (P < .05) of soybean hull inclusion in the diet on DM, OM, TDF, and GE total-tract digestibilities, as well as on calculated ME. Crude protein and fat digestibilities were unaffected by treatment. Based on these results, ileally cannulated dogs were fed diets containing 6.0, 7.5, or 9.0% soybean hulls (DM basis) in addition to diets containing either 0% supplemental fiber or 7.5% beet pulp (Exp. 3). Nutrient digestion at the ileum was unaffected by inclusion of supplemental fiber. Total tract digestion of DM, OM, and GE was lower ( P < .05) for diets containing supplemental fiber when compared with the diet containing 0% fiber. Crude protein and fat digestibilities were unaffected by treatment. There was no difference in nutrient digestibility between those diets containing soybean hulls and a diet containing beet pulp. Soybean hull inclusion in the diet resulted in a negative linear effect (P < .05) on calculated ME, in addition to lowering ME (P < .05) when compared with the 0% fiber control diet. Calculated ME for dogs fed a 7.5% beet pulp-containing diet was lower (P < .05) than that for dogs fed the soybean hull-containing diets. Results indicate that soybean hulls can be an effective dietary fiber source in dog diets.

Animal Feed↗

PubMed1999

Evaluation of selected high-starch flours as ingredients in canine diets.

Cereal grains represent 30 to 60% of the DM of many companion animal diets. Once incorporated into a diet, the starch component of these grains can provide an excellent source of ME. However, crystallinity and form of starch are variable and can cause incomplete digestion within the gastrointestinal tract. Diets fed in this experiment included one of six high-starch flours as the main source of carbohydrate. The flours originated from barley, corn, potato, rice, sorghum, and wheat. The diets were extruded and kibbled. Starch fraction concentrations of flours consisted of nearly 100% rapidly digestible starch (RDS) and slowly digestible starch (SDS) combined. Starch fraction concentrations of diets paralleled concentrations in flours. Flours varied widely in concentrations of CP, fat, starch, and total dietary fiber. Ileal OM and CP digestibilities were lowest for the potato flour treatment (74 and 64%, respectively). Ileal and total tract starch digestibilities were different (P<.05) among treatments; however, the starch component of all diets was nearly completely digested (>99%). Total tract digestibility of DM and OM was lowest for sorghum (80 and 84%, respectively) compared to all other diets. Crude protein digestibility was highest for corn (87%). Wet fecal weights tended (P<.08) to be greatest for dogs fed the barley treatment (175 g/d). However, dry fecal weights (dried at 55 degrees C) were greatest for dogs consuming the sorghum diet (51 g/d). Fecal scores were consistently greater (i.e., looser stools) for the barley treatment. Any of these flours could be used without negative effects on digestion at either the ileum or in the total tract. Fecal consistency data for dogs consuming the barley treatment indicate that diets containing large amounts (>50%) of barley may not be advantageous for dog owners who house their animals indoors for most of the day.

Animal Nutritional Physiological Phenomena↗

PubMed1998

Apparent digestibility of a debranched amylopectin-lipid complex and resistant starch incorporated into enteral formulas fed to ileal-cannulated dogs1.

The purpose of this study was to evaluate apparent digestibility in ileal-cannulated dogs fed enteral diets containing a debranched amylopectin-lipid complex (V-complex) or resistant starch. Six ileal-cannulated dogs were randomized into a replicated 3 x 3 Latin square design for determination of digestibility of three experimental treatments. Dietary treatments were as follows: 1) control; 2) V-complex; and 3) resistant starch. Diets were similar in chemical composition. Apparent digestibility of dry matter (DM), organic matter (OM) and carbohydrate by dogs fed the control diet was higher (P < 0.05) than for dogs consuming the other diets. Mean apparent digestibilities of carbohydrate for the control, V-complex and resistant starch diets were 89, 76 and 43%, respectively. Both DM and carbohydrate digestibility were lower (P < 0.05) for resistant starch compared with V-complex. Fecal dry and wet weights for dogs fed the control diet were lower (P < 0.05) than for those receiving either the resistant starch or V-complex treatments. Dogs fed the V-complex diet produced approximately 90 g less feces per day than dogs fed resistant starch. Dietary incorporation of V-complex to replace traditional carbohydrates may be beneficial for diabetic patients because of the decreased digestibility and subsequent glucose absorption rate. Furthermore, incorporation of resistant starch into enteral formulas may improve gastrointestinal tract health status as a result of increased fecal bulk, potential dilution of toxins in the intestinal lumen and greater production of short-chain fatty acids.

Amylopectin↗