Fecal Energy Loss Research Articles

Fecal fat and energy loss in pancreas exocrine insufficiency: the role of pancreas enzyme replacement therapy

Background: Chronic pancreatitis (CP) can lead to severe pancreatic exocrine insufficiency (PEI). Pancreatic enzyme replacement therapy (PERT) is well established, but knowledge of the physiological response to increasing doses on fecal fat- and energy loss is scarce.Methods: We included 10 patients with CP and established PEI and 12 healthy controls for a prospective interventional study. Subjects received no PERT in the first week followed by four weeks PERT incrementally increasing doses every week. For each week, three-day stool collection followed three days registration of nutritional intake. We measured the fecal output of fat and energy by van de Kamer titration and decomposition vessel calorimetry, respectively. We calculated fecal fat- and energy loss per day, the coefficient of fat absorption (CFA) and coefficient of energy absorption (CEA).Results: Without PERT treatment, CP patients with PEI had significantly higher daily fecal fat and energy loss (p = .022; p = .035) compared to HC. In CP patients, there was a significant reduction of fecal fat and energy loss (p = .045; p = .037) when PERT doses reached maximum intake of 75,000 units per meal. In CP patients, there was a strong positive correlation between fecal loss of energy and fat (r = 0.99), and between fecal loss of energy and daily stool weight (r = 0.97). CFA and CEA correlated negatively with daily fecal fat loss (r = −0.72) and fecal energy loss (r = −0.65).Conclusions: PERT reduces fecal energy and fat loss in patients with CP and PEI. Fecal energy loss in CP patients is strongly dependent on fecal fat loss, and on fecal weight.

The effect of silage type on animal performance, energy utilisation and enteric methane emission in lactating dairy cows

The present study aimed to investigate the effect of silage type on dry matter (DM) intake, nutrient digestibility, energy utilisation and methane (CH4) emission. Six late lactating Holstein dairy cows were used in a replicated 3 × 3 Latin square design study with three treatments (grass silage (GS), maize silage (MS) and whole-crop wheat silage (WCWS)) and three periods (3 weeks/period). All animals were offered forage ad libitum and 5.55 kg/day of a concentrate supplement, which contained (DM basis) 66.0% rapeseed meal, 28.3% soyabean meal and 5.7% a mineral/vitamin supplement. During each period, animals were subject to digestibility, CH4 and heat production measurements during the final 6 days using calorimeter chambers. The results demonstrated that total DM intake for MS and WCWS diets were higher (P < 0.001) than for the GS diet. Faecal energy and heat production loss for the GS diet were lower (P < 0.01) than for MS and WCWS diets. In contrast, cows fed the GS diet had higher (P < 0.05) urine energy loss compared with MS and WCWS diets. In comparison with the GS and MS diets, WCWS diet produced a lower CH4 loss per kg DM and organic matter intake (P < 0.01), and CH4 energy output as a proportion of gross energy and metabolisable energy intake (P < 0.05). The present study demonstrates that choice of forage types affects energy utilisation and CH4 emission in dairy cows.

Effects of feeding monensin to bred heifers fed in a drylot on nutrient and energy balance.

The objective of this study was to determine if feeding monensin would improve diet digestion, energy and nitrogen balance in bred heifers receiving a limit-fed corn stalk-based diet. Sixteen pregnant Meat Animal Research Center (MARC) III composite heifers were used in a 161-d completely randomized design. Heifers were randomly assigned to one of two treatments, no monensin (CON) or 150 mg/d monensin (MON), with eight heifers in each treatment group. Heifers were limit-fed a corn stalk-based diet at 100% of MEm requirements. Effects of monensin on energy and nitrogen balance were determined via total fecal and urine collections and open-circuit respiration calorimetry. Total fecal and urine collection occurred on d 14, 42, and 161 of monensin feeding, and calorimetry measurements were made on d 0, 3, 14, 28, 42, and 161 of monensin feeding. DMI was not different (P = 0.94) for CON and MON heifers and, by design, increased (P < 0.01) from d 14 to d 161 of the trial to account for increasing fetal growth requirements. No differences (P = 0.91) in GE intake were observed between CON and MON heifers, and DE and ME intakes did not differ (P > 0.58) with monensin inclusion. DM, OM, NDF, and ADF digestion did not differ (P > 0.52) between treatments. Fecal, methane, urinary, and heat energy losses were not different (P > 0.16) for MON and CON heifers. Methane production was not different between treatments when expressed as daily liters of methane (P = 0.40); however, MON heifers produced 7% less (P = 0.03) methane per day than CON heifers when expressed as liters of methane produced on a metabolic body weight (MBW) basis. Furthermore, monensin had no effect (P = 0.36) on overall retained energy (RE). Nitrogen intake and excretion was not different (P > 0.13) between treatment groups. Results of this experiment indicate that adding monensin to limit-fed, corn stalk-based diets may not have a large effect on the energy and nitrogen balance of confined heifers.

Evidence for increasing digestive and metabolic efficiency of energy utilization with age of dairy cattle as determined in two feeding regimes

The changes taking place with age in energy turnover of dairy cattle are largely unknown. It is unclear whether the efficiency of energy utilization in digestion (characterized by faecal and methane energy losses) and in metabolism (characterized by urine and heat energy losses) is altered with age. In the present study, energy balance data were obtained from 30 lactating Brown Swiss dairy cows aged between 2 and 10 years, and 12 heifers from 0.5 to 2 years of age. In order to evaluate a possible dependence of age effects on diet type, half of the cattle each originated from two herds kept at the same farm, which were fed either on a forage-only diet or on the same forage diet but complemented with 5 kg/day of concentrate since their first calving. During 2 days, the gaseous exchange of the animals was quantified in open-circuit respiration chambers, followed by an 8-day period of feed, faeces, urine and milk collection. Daily amounts and energy contents were used to calculate complete energy balances. Age and feeding regime effects were analysed by parametric regression analysis where BW, milk yield and hay proportion in forage as consumed were considered as covariates. Relative to intake of gross energy, the availability of metabolizable energy (ME) increased with age. This was not the result of an increasing energy digestibility, but of proportionately lower energy losses with methane (following a curvilinear relationship with the greatest losses in middle-aged cows) and urine (continuously declining). The efficiency of utilization of ME for milk production (kl) increased with age. Potential reasons include an increase in the propionate-to-acetate ratio in the rumen because of a shift away from fibre degradation and methane formation as well as lower urine energy losses. The greater kl allowed older cows to accrete more energy reserves in the body. As expected, offering concentrate enhanced digestibility, metabolizability and metabolic utilization of energy. Age and feeding regime did not interact significantly. In conclusion, older cows seem to have digestive and metabolic strategies to use dietary energy to a certain degree more efficiently than younger cows.

The effects of feeding increasing concentrations of corn oil on energy metabolism and nutrient balance in finishing beef steers1

The use of an added lipid is common in high-concentrate finishing diets. The objective of our experiment was to determine if feeding increasing concentrations of added dietary corn oil would decrease enteric methane production, increase the ME:DE ratio, and improve recovered energy (RE) in finishing beef steers. Four treatments were used in a replicated 4 × 4 Latin square ( = 8; initial BW = 397 kg ± 3.8). Data were analyzed using a Mixed model with the fixed effects of period and dietary treatment and random effects of square and steer within square. Treatments consisted of: (1) 0% added corn oil (Fat-0); (2) 2% added corn oil (Fat-2); (3) 4% added corn oil (Fat-4); (4) 6% added corn oil (Fat-6). Dry matter intake or GE intake did not differ across diets ( ≥ 0.39). As a proportion of GE intake, fecal energy loss, DE, and urinary energy loss did not differ by treatment ( ≥ 0.27). Additionally, methane energy produced decreased linearly as corn oil increased in the diet ( < 0.01). No differences were detected in ME loss as a proportion of GE intake ( ≥ 0.98). However, the ME:DE ratio increased linearly ( < 0.01; 93.06, 94.10, 94.64, and 95.20 for Fat-0, Fat-2, Fat-4, and Fat-6, respectively) as corn oil inclusion increased in the diet. No differences in RE or heat production as a proportion of GE intake were noted ( ≥ 0.59) and dry matter digestibility did not differ across diets ( ≥ 0.36). Digestibility of NDF as a proportion of intake responded quadratically increasing from 0% corn to 4% corn oil and decreasing thereafter ( = 0.02). Furthermore, ether extract digestibility as a proportion of intake responded quadratically, increasing from 0% to 4% corn oil inclusion before reaching a plateau ( < 0.01). As a proportion of GE intake, RE as protein decreased linearly as corn oil was increased in the diet ( < 0.01). As a proportion of total energy retained, RE as protein decreased when corn oil increased from 0% to 6% of diet DM ( < 0.01). Similarly, RE as fat and carbohydrate as a proportion of GE intake increased linearly as corn oil increased in the diet ( = 0.05). From these data, we interpret that adding dietary fat decreases enteric methane production and increases the ME:DE ratio, in addition to increasing the amount of energy retained as fat and carbohydrate.

A model explaining protracted weight loss after Roux en Y gastric by-pass bariatric surgery

Introduction: Despite evidence that Roux en Y gastric by-pass (RYGB) does not generally lead to a sustained decrease in dietary intake or appetite loss, this form of treatment is the most effective method of producing sustained weight loss in morbidly obese subjects. Animal and clinical studies have shown that RYGB induces metabolic changes enhancing energy expenditure at rest and particularly in the post-prandial period, so-called âÂ?Â?diet-induced thermogenesisâÂ? (DIT) and also to increased faecal energy loss via both fat and undigested protein. A key question is what is the cause of the enhanced DIT following RYGB? Saeidi et al and Cavin et al. have reported that after RYGB in obese rats, the alimentary limb (AL) becomes hyperplastic and hypertrophic showing up-regulation of the glucose transporter GLUT1 in enterocyte basolateral membranes, also cytoplasmic hexokinase 2 and increased intraluminal metabolism of glucose as demonstrated by 2-deoxy-2-[18F] fluoro-D-glucose (18FDG) positron emission tomography. Sustained weight loss due to Roux en Y gastric bypass surgery (RYGB) may either be the result of improved incretin response to or a change in energy balance. A recent computer model of human glucose absorption and metabolism has been adapted to provide an explanation of both the increased DIT and weight-loss after RYGB. There are three likely mechanisms explaining the RYGB induced sustained weight loss: Increased sensitivity to incretins gastric inhibitory polypeptide GIP and glucagon-like peptide 1 GLP-1; increased leakage of glucose from the splanchnic circulation back into the small intestinal lumen via either transcellular route. This results from increased expression of glucose transporters at both the enterocyte basolateral and apical membranes, i.e. GLUT1 and GLUT2, or to inflammation-induced increased paracellular leakage. Overgrowth of facultative aerobic bacteria within the small intestine leads to enhanced luminal conversion of glucose to CO2 with consequent depletion of net energy absorption. The computer model simulates all of the combinations of these conditions and the observed decreases in plasma glucose and insulin concentrations along with increase in post prandial and fasting metabolic rates following RYGB. A combination of all three factors is likely to be the explanation for the success of RYGB. This raises the interesting consideration as to whether a non-surgical intervention which simulates these effects might be as efficacious as RYGB in producing sustained weight loss in morbidly obese subjects.

Impact of phytogenic feed additives on growth performance, nutrient digestion and methanogenesis in growing buffaloes

Twenty growing buffalo calves were fed on a basal diet consisting of wheat straw and concentrate mixture in a randomised block design, to study the effect of feeding phytogenic feed additives on growth performance, nutrient utilisation and methanogenesis. The four groups were viz. control (no additive), Mix-1 (ajwain oil and lemon grass oil in 1 : 1 ratio @ 0.05% of dry matter intake), Mix-2 (garlic and soapnut in 2 : 1 ratio @ 2% of DMI) and Mix-3 (garlic, soapnut, harad and ajwain in 2 : 1 : 1 : 1 ratio @ 1% of DMI). The experimental feeding was continued for a period of 8 months. A metabolism trial was conducted after 130 days of feeding. Methane emission from animals was measured by open-circuit indirect respiration calorimeter. The feed conversion efficiency was higher by 9.5% in Mix-1, 7% in Mix-2 and 10.2% in Mix-3 group than in control. The digestibility of nutrients was similar except crude protein, which was improved (P &lt; 0.05) in treatment groups. All buffalo calves were in positive nitrogen balance. Comparative faecal nitrogen decreased and urinary nitrogen increased in all the supplemented groups compared with in the control group. Methane emission (in terms of L/kg dry matter intake and L/kg digestible dry matter intake) was reduced by 13.3% and 17.8% in Mix-1, 10.9% and 13.5% in Mix-2 and 5.1% and 9.8% in Mix-3 groups as compared with control. When expressed in L/kg organic matter intake and L/kg digestible organic matter intake, methane production was reduced by 13.3% and 16.7% in Mix-1, 10.9% and 12.9% in Mix-2 and 5.1% and 8.4% in Mix-3 groups compared with the control group. These feed additives inhibited methane emission without adversely affecting feed utilisation by the animals. The faecal energy, urinary energy and methane energy losses were not affected (P &gt; 0.05) due to feeding of these additives. Further, long-term feeding experiments should be conducted on a large number of animals to validate these effects before they can be recommended for use at a field level.

Net energy gained by northern fur seals (Callorhinus ursinus) is impacted more by diet quality than by diet diversity

Understanding whether northern fur seals (Callorhinus ursinus (L., 1758)) are negatively affected by changes in prey quality or diversity could provide insights into their on-going population decline in the central Bering Sea. We investigated how six captive female fur seals assimilated energy from eight different diets consisting of four prey species (walleye pollock (Gadus chalcogrammus Pallas, 1814, formerly Theragra chalcogrammus (Pallas, 1814)), Pacific herring (Clupea pallasii Valenciennes in Cuvier and Valenciennes, 1847), capelin (Mallotus villosus (Müller, 1776)), and magister armhook squid (Berryteuthis magister (Berry, 1913))) fed alone or in combination. Net energy was quantified by measuring fecal energy loss, urinary energy loss, and heat increment of feeding. Digestible energy (95.9%–96.7%) was high (reflecting low fecal energy loss) and was negatively affected by ingested mass and dietary protein content. Urinary energy loss (9.3%–26.7%) increased significantly for high-protein diets. Heat increment of feeding (4.3%–12.4%) was significantly lower for high-lipid diets. Overall, net energy gain (57.9%–83.0%) was affected by lipid content and varied significantly across diets. Mixed-species diets did not provide any energetic benefit over single-species diets. Our study demonstrates that diet quality was more important in terms of energy gain than diet diversity. These findings suggest that fur seals consuming low-quality prey in the Bering Sea would be more challenged to obtain sufficient energy to satisfy energetic and metabolic demands, independent of high prey abundance.

Digestive parameters and energy assimilation of Cape porcupine on economically important crops

To better understand how Cape porcupines are able to successfully occupy many agricultural lands, we studied their digestive parameters and energy assimilation when fed three economically important agricultural crops (potatoes [Solanum tuberosum], sweet potatoes [Ipomoea batatas] and butternut [Juglans cinerea]). Daily food intake, daily gross energy intake, daily faecal energy loss, daily energy assimilated, daily water intake and apparent assimilation efficiency were calculated for each porcupine and for each diet trial. Cape porcupines maintained body mass on all three experimental diets and energy intake ranged from 3 002.36 kJ kg−1 d−1 (potato) to 4 499.00 kJ kg−1 d−1 (sweet potato). The moisture content in each experimental diet was relatively high (>60%) and preformed water intake of winter acclimated Cape porcupines ranged from 60 ml kg−1 d−1 (potato) to 100 ml kg−1 d−1 (sweet potato). Assimilation efficiencies were high (>85%) on all three diets. Cape porcupines ingested c. 1.5–2.7 kg of each crop daily, translating to potentially large economic impacts on farmers. Knowledge and understanding of Cape porcupine food intake and dietary requirements give insight to their potential impact on commercial crops. This may aid in developing management and conservation strategies needed to manage this human–wildlife conflict.

Effects of dry-rolled or high-moisture corn with twenty-five or forty-five percent wet distillers' grains with solubles on energy metabolism, nutrient digestibility, and macromineral balance in finishing beef steers.

The effects of feeding a dry-rolled corn-based diet (DRCB) or a combination of a high-moisture corn-based diet (HMCB) with dry-rolled corn (DRC; 2:1 ratio of high-moisture corn [HMC] and DRC) with 25 and 45% wet distillers' grains with solubles (WDGS) on energy metabolism and nutrient and mineral balance were evaluated in 8 finishing steers using a replicated Latin square design. The model included the fixed effects of dietary treatment, the WDGS × diet type interaction, and period and the random effects of square and steer within square were also included. Treatments consisted of a DRCB with 25% WDGS, a DRCB with 45% WDGS, a combination of HMCB and DRC with 25% WDGS, and a combination of HMCB and DRC with 45% WDGS. Cattle consuming DRCB consumed a greater amount of DM ( < 0.01) and GE intake was also greater when feeding DRCB with 25% WDGS than when feeding DRCB with 45% WDGS ( < 0.01). As a proportion of GE intake, cattle consuming HMCB had a greater fecal energy loss ( = 0.01). Digestible energy loss as a proportion of GE intake was greater when cattle were fed DRCB than when cattle were fed HMCB ( = 0.01) and when WDGS was included at 45% of DM ( = 0.05). As a proportion of GE intake, cattle consuming DRCB and 25% WDGS respired a greater amount of methane (Mcal) than cattle consuming 45% WDGS. As a proportion of GE intake, ME was greater in DRCB than in HMCB ( = 0.01). Within HMCB, 45% WDGS had more megacalories of retained energy than 25% WDGS. Nitrogen excretion (g) was greater in the urine ( < 0.01) and feces ( < 0.05) when 45% WDGS was included. As a proportion of N intake, total N retained was greater when a greater amount of WDGS was included in the diet ( = 0.05). Digestibility was greater in DRCB than in HMCB ( = 0.02). Starch intake, excretion, and digestibility as a proportion of intake were greater in DRCB than in HMCB ( < 0.01) and when WDGS was included at 25% than when WDGS was included at 45% of the diet ( < 0.01). Intake of ether extract was greater in HMCB when 45% WDGS was included ( < 0.01), and fecal excretion was greater in diets including 25% WDGS than in diets including 45% WDGS ( = 0.02). Sulfur intake was greater as the inclusion of WDGS increased from 25 to 45% ( < 0.01). We interpret that if the basal concentrate portion of the diet is based on HMC, adding an increased amount of WDGS can improve retained energy, and within DRCB, more energy is retained as fat and carbohydrate when cattle were fed 25% WDGS.

Refractory celiac disease and EATL patients show severe malnutrition and malabsorption at diagnosis

Refractory celiac disease type II (RCDII) and EATL (Enteropathy Associated T-cell Lymphoma) are (pre)malignant complications of celiac disease (CD). Data on malnutrition and intestinal absorption is lacking in these patients. Therefore, the aim of the study is to comprehensively assess nutritional status and intestinal absorption capacity of patients with RCDII and EATL, compared with data of newly diagnosed CD patients. Observational study in tertiary care setting in RCDII (n=24, 63.8±8.2y), EATL (n=25, 62.3±5.7y) and CD patients (n=43, 45.6±14.8y). At diagnosis, anthropometry (BMI, unintentional weight loss, fat-free mass index (FFMI), handgrip strength (HGS), nutritional intake, fecal losses and Resting Energy Expenditure (REE)) were assessed. Low BMI (<18.5) was more often observed in RCDII patients than in CD or EATL patients (in 33%, 12% and 12%, respectively, p=0.029). EATL patients more frequently had unintentional weight loss (>10%) than CD or RCDII patients (in 58%, 19% and 39% of patients, respectively; p=0.005/0.082). Energy malabsorption (<85%) was detected in 44% and 33% of RCDII and EATL patients, vs 21.6% in CD (NS). Fecal energy losses were higher in RCDII than in CD patients (589±451 vs 277±137kcal/d, p=0.017). REE was underestimated by predicted-REE with>10% in 60% of RCDII, 89% of EATL, and 38% of CD patients (p=0.006). Low FFMI and HGS were detected in one third and two thirds of all patients, respectively. The nutritional status of patients with RCDII and EATL is inferior compared with untreated naïve CD patients at presentation. Both malabsorption as well as hypermetabolism contribute to malnutrition.

Gut hormones in the treatment of short-bowel syndrome and intestinal failure.

The approval of teduglutide, a recombinant analog of human glucagon-like peptide (GLP) 2, by the US Food and Drug Administration (Gattex) and the European Medicines Agency (Revestive) has illustrated the potential of selected gut hormones as treatments in patients with short-bowel syndrome and intestinal failure. Gut hormones may improve the structural and functional intestinal adaptation following intestinal resection by decreasing a rapid gastric emptying and hypersecretion, by increasing the intestinal blood flow, and by promoting intestinal growth. This review summarizes the findings from phase 2 and 3 teduglutide studies, and pilot studies employing GLP-1 and agonists for this orphan condition. In a 3-week, phase 2, metabolic balance study, teduglutide increased the intestinal wet weight absorption by approximately 700 g/day and reduced fecal energy losses by approximately 0.8 MJ/day (∼200 Kcal/day). In two subsequent 24-week, phase 3 studies, teduglutide reduced the need for parenteral support in the same magnitude. Adverse events were mainly of gastrointestinal origin and consistent with the known mechanism of action of teduglutide. Pilot studies suggest that GLP-1 may be less potent. Synergistic effects may be seen by co-treatment with GLP-2. Gut hormones promote intestinal adaptation and absorption, decreasing fecal losses, thereby decreasing or even eliminating the need for parenteral support. This will aid the intestinal rehabilitation in these severely disabled short-bowel syndrome patients.

Enteric Methane Emission, Energetic Efficiency and Energy Requirements for the Maintenance of Beef Cattle in the Tropics

This study was conducted to determine the energy balance of beef cattle by indirect animal calorimetry utilizing a ventilated head box respiration system. Fifteen native Thai bulls were randomly allocated to one of three dietary metabolizable energy intake (MEI) levels (1.1 × maintenance, 1.5 × maintenance and 1.9 × maintenance) in a completely randomized design for a 116 day feeding trial. Animals were allocated to individual metabolic cages for the determination of digestibility and energy balance. Heat production was determined from oxygen consumption, carbon dioxide and methane production. The results showed that dry matter, organic matter and crude protein intake were increased (P 0.05) by MEI levels. The energy loss in feces and urine (% of gross energy intake) were not different (P > 0.05); however, enteric methane conversion rate (% of methane energy loss per gross energy intake) and heat energy production loss (% gross energy intake) were linearly decreased (P < 0.01) with increasing MEI levels. Methane conversion rates ranged from 8.4 to 10.0% and appeared to have been underestimated by the Intergovernmental Panel on Climate Change 6.5% default values set for cattle fed low quality crop residues and by-products. The estimate of metabolizable energy requirements for maintenance was measured using linear regression analysis derived for native Thai cattle was 520 kilojoules per kilogram of metabolic body weight per day. Increased dietary intake levels reduced enteric methane emissions in beef cattle fed on tropical feedstuffs. The results of the present study indicated that greater dietary intake feeding strategy in cattle fed above the maintenance level resulted in improved energetic efficiency utilization, and thus improved energy retention because of the reduction of enteric methane energy emission and heat production. Discipline: Animal industry Additional key words: cattle, energy requirements, enteric methane, tropical This paper reports results obtained in the international project on “Establishment of feeding standard of beef cattle and feedstuff database in Indochina.” The Japan International Research Center for Agricultural Sciences, Department of Livestock Development, Ministry of Agriculture and Cooperatives, Thailand, and Khon Kaen University took responsibility for all subjects picked up in the project, implemented main subjects jointly and managed the project. Since it is essential to construct a regional research cooperation network for the efficient achievement of the targets, other research organizations such as Mahasarakham University, Ubon Ratchatanee University, Rajamangala University of Technology-Isan, Suranaree University of Technology, Chiang Mai University, Maejo University, Prince of Songkla University, National University of Laos, Lao PDR, and Royal University of Agriculture, Cambodia were also involved in the project. The project was implemented during the five-year period from 2006 to March 2011. Present address: 4 Division of Animal Sccience, Faculty of Technology, Mahasarakham University (Mahasarakham 44150, Thailand) 5 NARO Institute of Livestock and Grassland Science (Tsukuba, Ibaraki 305-0901, Japan) *Corresponding author: e-mail: kritapon@kku.ac.th Received 2 December 2014; accepted 31 March 2015.

Effects of dietary glycerin inclusion at 0, 5, 10, and 15 percent of dry matter on energy metabolism and nutrient balance in finishing beef steers.

Expansion of the biodiesel industry has increased the glycerin (GLY) supply. Glycerin is an energy-dense feed that can be used in ruminant species; however, the energy value of GLY is not known. Therefore, the effects of GLY inclusion at 0, 5, 10, and 15% on energy balance in finishing cattle diets were evaluated in 8 steers (BW = 503 kg) using a replicated Latin square design. Data were analyzed with the fixed effects of dietary treatment and period, and the random effects of square and steer within square were included in the model. Contrast statements were used to separate linear and quadratic effects of GLY inclusion. Glycerin replaced dry-rolled corn (DRC) at 0, 5, 10, and 15% of dietary DM. Dry matter intake decreased linearly (P = 0.02) as GLY increased in the diet. As a proportion of GE intake, fecal energy loss tended to decrease linearly (P < 0.07), and DE also tended to increase linearly (P = 0.07) as dietary level of GLY increased. Urinary energy loss was not different (P > 0.31) as a proportion of GE as GLY increased in the diet. Methane energy loss as a proportion of GE intake tended to respond quadratically (P = 0.10), decreasing from 0 to 10% GLY inclusion and increasing thereafter. As a proportion of GE intake, ME tended to respond quadratically (P = 0.10), increasing from 0 to 10% GLY and then decreasing. As a proportion of GE intake, heat production increased linearly (P = 0.02) as GLY increased in the diet. Additionally, as a proportion of GE intake, retained energy (RE) tended to respond quadratically (P = 0.07), increasing from 0 to 10% GLY inclusion and decreasing thereafter. As a proportion of N intake, urinary and fecal N excretion increased linearly (P < 0.04) as GLY increased in the diet. Furthermore, grams of N retained and N retained as a percent of N intake both decreased linearly (P < 0.02) as GLY increased in the diet. Total DM digestibility tended (P < 0.10) to respond quadratically, increasing at a decreasing rate from 0 to 5% GLY inclusion. Overall, RE tended to decrease as GLY increased in the diet in conjunction with a decrease in N retention, which could indicate an increased metabolic cost to the animal associated with feeding GLY. Based on RE, the feeding value of GLY in high-concentrate diets is greater than DRC at 5 and 10% of DM but less at 15% of DM.

Leptin deficient ob/ob mice and diet-induced obese mice responded differently to Roux-en-Y bypass surgery

Weight regain contributes to the therapeutic failure in 15-20% of type 2 diabetic patients after Roux-en-Y gastric bypass surgery (RYGB), and the mechanism remains largely unknown. This study was conducted to explore the mechanism of weight regain. Wild-type (WT) diet-induced obese (DIO) mice were used to mimic human obesity, and ob/ob mice were used for leptin deficiency-induced obesity. Two groups of mice were compared in weight regain for 10 months after RYGB. Weight loss, food intake, fecal energy loss and energy expenditure were monitored in the study of weight regain. Fasting insulin, insulin tolerance and homeostatic model assessment-insulin resistance were tested for insulin sensitivity under the weight regain. Weight loss from RYGB and calorie restriction was compared for the impact in insulin sensitivity. In WT mice, RYGB induced a sustained weight loss and insulin sensitization over the sham operation in this 10-month study. However, RYGB failed to generate the same effects in leptin-deficient ob/ob mice, which suffered a weight regain over the pre-surgery level. In ob/ob mice, body weight was reduced by RYGB transiently in the first week, recovered in the second week and increased over the baseline thereafter. Weight loss was induced by RYGB relative to that of sham mice, but the loss was not sufficient to keep body weight below the pre-surgery levels. In addition, insulin sensitivity was not improved by the weight loss. The response to RYGB was improved in ob/ob mice by 2 weeks of leptin treatment. Weight loss from calorie restriction had an equivalent effect on insulin sensitization compared with that of RYGB. Those data demonstrate that ob/ob mice and DIO mice responded differently to RYGB surgery, suggesting that leptin may be one of the factors required for RYGB to prevent weight regain and diabetes recurrence.

Malabsorption plays a major role in the effects of the biliopancreatic diversion with duodenal switch on energy metabolism in rats

BackgroundThe mechanisms underlying the metabolic benefits of the biliopancreatic diversion with duodenal switch (BPD/DS) have not been clarified. The objective of this study was to investigate the metabolic roles of sleeve gastrectomy (SG) and duodenal switch (DS) as main surgical components of BPD/DS. MethodsBPD/DS, SG, and DS surgeries were performed on chow-fed nonobese Wistar rats. Weight and energy intake were recorded during 8 postsurgical weeks. Glucagon-like peptide 1 (GLP-1), peptide tyrosine-tyrosine (PYY), glucose-dependent insulinotropic peptide, and ghrelin were measured pre- and postprandially at weeks 3 and 8, after surgery. Body composition, muscle, liver, and adipose tissue weights were measured. Gut morphometry and the presence and distribution of GLP-1 and PYY (L-cells) in the gut were determined using histochemical techniques. ResultsCompared with sham, BPD/DS and DS led to significant reductions in weight gain, percentage of fat, and adipose tissue weight. These effects were accompanied by a reduction in digestible energy intake associated with fecal energy loss due to DS. BPD/DS and DS produced intestinal hypertrophy, as well as higher plasma GLP-1 and PYY in both fasted and refed states. It is noteworthy that none of those alterations were observed after SG, which nonetheless led to transient postoperative reduction in gross energy intake and weight. Similar to BPD/DS, SG alone produced a reduced meal size and an enhanced postprandial depression of plasma ghrelin. ConclusionBPD/DS results in metabolic benefits, which appear largely caused by food malabsorption due to DS. The elevation of anorectic GLP-1 and PYY are additional consequences of DS, which, together with malabsorption, could promote the metabolic benefits of BPD/DS.

Effects of resistant starch on behaviour, satiety-related hormones and metabolites in growing pigs

Resistant starch (RS) has been suggested to prolong satiety in adult pigs. The present study investigated RS-induced changes in behaviour, satiety-related hormones and metabolites in catheterized growing pigs to explore possible underlying mechanisms for RS-induced satiety. In a cross-over design with two 14-day periods, 10 pigs (initial BW: 58 kg) were assigned to two treatments comprising diets containing either 35% pregelatinized starch (PS) or 34% retrograded starch (RS). Diets were isoenergetic on gross energy. Pigs were fed at 2.8× maintenance. Postprandial plasma response of satiety-related hormones and metabolites was measured at the end of each period using frequent blood sampling. Faecal and urinary energy losses were measured at the end of each period. Behaviour was scored 24 h from video recordings using scan sampling. Energy digestibility and metabolizability were ~6% lower in RS compared with PS diet (P<0.001), and metabolizable energy (ME) intake was ~3% lower in RS-fed than in PS-fed pigs (P<0.001). RS-fed pigs showed less feeder-directed (P=0.001) and drinking (P=0.10) behaviours than PS-fed pigs throughout the day. Postprandial peripheral short-chain fatty acid (SCFA) levels were higher in RS-fed than in PS-fed pigs (P<0.001). Postprandial glucose and insulin responses were lower in RS-fed than in PS-fed pigs (P<0.001). Triglyceride levels were higher in RS-fed than in PS-fed pigs (P<0.01), and non-esterified fatty acid levels did not differ between diets (P=0.90). Glucagon-like peptide-1 (GLP-1) levels were lower in RS-fed than in PS-fed pigs (P<0.001), and peptide tyrosine tyrosine (PYY) levels did not differ between diets (P=0.90). Blood serotonin levels were lower (P<0.001), whereas monoamine oxidase activity (P<0.05) and tryptophan (P<0.01) levels were higher in RS-fed than in PS-fed pigs. Despite a lower ME intake, RS seemed to prolong satiety, based on behavioural observations. Possible underlying mechanisms for RS-induced satiety include increased 24 h plasma SCFA levels, and decreased postprandial glucose and insulin responses. GLP-1 and PYY seemed not to play a role in RS-induced satiety. Low blood serotonin levels in RS-fed pigs suggested a difference in intestinal serotonin release between treatments. Increased postprandial plasma triglyceride levels corresponded with increased SCFA levels, but it is unclear whether triglycerides may have signalled satiety in RS-fed pigs.

Effects of decreased dietary roughage concentration on energy metabolism and nutrient balance in finishing beef cattle1

The optimal roughage concentration required in feedlot diets changes continuously for many reasons such as source, availability, price, and interaction with other ingredients in the diet. Wet distillers grains and solubles (WDGS) are common in finishing diets and they contain relatively high amounts of fiber compared with other grains they replace. Therefore, concentration of roughage could be altered when WDGS are included in feedlot diets. There has been very little data published regarding the effects of roughage concentration on energy metabolism and nutrient balance in beef steers. Therefore, the effects of roughage concentration in dry-rolled corn (DRC)-based diets containing 25% WDGS were evaluated in 8 steers (BW = 362 ± 3.71 kg) using a replicated Latin square. Data were analyzed with the fixed effects of dietary treatment and period and random effects of square and steer within square were included in the model. Diets consisted of 25% WDGS and the balance being DRC and coarsely ground alfalfa hay (AH) replacing corn at 2% (AH-2), 6% (AH-6), 10% (AH-10), and 14% (AH-14) of dietary dry matter. As a proportion of GE intake, fecal energy loss increased linearly (P = 0.02), and DE decreased linearly (P = 0.02) as dietary level of AH increased. Methane energy loss, as a proportion of GE intake, increased linearly (P < 0.01) and ME decreased linearly (P < 0.01) as dietary concentration of AH increased. Heat production tended (P = 0.10) to decrease reaching a minimum of 10% AH and increased from 10 to 14% AH inclusion. Moreover, as a proportion of GE intake, retained energy (RE) decreased (P < 0.01) as AH level increased in the diet. Reasons for the decrease in RE are 1) the increase in fecal energy loss that is associated with decreased ruminal digestibility of NDF when AH replaced DRC and the shift in ruminal VFA produced, 2) the decreased energy available for animal retention when NDF increased linearly as AH increased in the diet, and 3) the methane and heat energy associated with digestion of the fibrous portion of the AH. Neutral detergent fiber and OM excretion also increased linearly (P < 0.01) with increasing AH in the diet. The increased NDF and OM excretion were likely caused by the difference in digestibility of AH and DRC.

Modern treatment of short bowel syndrome

Recently, the US Food and Drug Administration and the European Medicines Agency approved the glucagon-like peptide 2 analogue, teduglutide, for the treatment of short bowel syndrome (SBS), and this review describes the physiological basis for its clinical use. By affecting the intestinal neuroendocrine system, hormones may promote the growth of the intestinal mucosa, restore a more normal gastric emptying and secretion, stimulate intestinal blood flow, increase intestinal barrier function, immunity and absorption, and thereby promote structural and functional adaptation following intestinal resection. In a 3-week, phase 2, metabolic balance study, teduglutide increased intestinal wet weight absorption by ∼700 g/day and reduced faecal energy losses by ∼0.8 MJ/day. In two subsequent 24-week, phase 3 studies in SBS patients with intestinal failure (SBS-IF), teduglutide reduced the need for parenteral support in the same magnitude. Teduglutide adds incremental benefit to the limited medical treatment armamentarium in SBS patients. Modern treatments should aim to maximize remnant intestinal absorption, decrease malabsorption and accompanying symptoms, reduce the need, burdens and complications related to parenteral support, and ultimately improve the health-related quality of life in SBS-IF patients. Future research should target and implement other key hormones with similar effects, thereby promoting intestinal adaptation and rehabilitation in SBS patients.

Acute effects of continuous infusions of glucagon-like peptide (GLP)-1, GLP-2 and the combination (GLP-1 + GLP-2) on intestinal absorption in short bowel syndrome (SBS) patients. A placebo-controlled study

Background and aimsThe ileocolonic brake is impaired in short bowel syndrome (SBS) patients with distal bowel resections. An attenuated meal-stimulated hormone secretion may cause gastric hypersecretion, rapid gastric and intestinal transit and a poor adaptation. Attempting to restore this ileocolonic brake, this study evaluated the acute effects of continuous intravenous administration of glucagon-like peptide (GLP) 1 and 2, alone or in combination, on gastrointestinal function in SBS patients. MethodsSBS patients were admitted 4 times for identical 72-h balance studies, where infusions (1pmol/kg/min) of GLP-1, placebo (saline), GLP-2 and GLP-1+2 (1pmol/kg/min of each), were provided. Patients filled out a VAS questionnaire regarding subjective symptoms during treatments. Bone mineral content, body-weight and -composition were measured using DEXA scans. Blood glucose, insulin, pro insulin C-peptide and GLP concentrations were measured in relation to a standardized breakfast. ResultsNine SBS patients (5 women/4 men, aged 52±11) were enrolled and completed the study; 7 had end-jejunostomies, 2 had 50% of colon-in-continuity. All treatments significantly reduced the fecal wet weight, energy, nitrogen, sodium and potassium losses compared to placebo. However, only GLP-2 containing treatments increased absolute absorption of wet weight and sodium. Only GLP-1+2 improved the hydrational status evaluated by DEXA increases in the fat mass and calculated total body weight. GLP-1 and GLP-1+2 reduced the post-prandial blood glucose levels. A tendency of nausea and reduced appetite was seen in relation to GLP-1 treatment, but this was ameliorated by the co-administration of GLP-2. ConclusionGLP-1 decreased diarrhea and fecal excretions in SBS patients, but it seems less potent than GLP-2. The combination of GLP-1+2 numerically provided additive effects on intestinal absorption compared to either peptide given alone. Larger, long-term studies should further assess the potential of the glucagon-like peptides or analogs, alone or in combination, in the treatment of SBS patients.