Individual Metabolic Cages Research Articles

Tropical tanniniferous legumes used as an option to mitigate sheep enteric methane emission

This study presents the first results from Brazil using SF(6) tracer technique adapted from cattle to evaluate the capability of condensed tannin (CT) present in three tropical legume forages, Leucaena leucocephala (LEU), Styzolobium aterrimum (STA), and Mimosa caesalpiniaefolia Benth (MIM) to reduce enteric CH(4) production in Santa Inês sheep. Twelve male lambs [27.88 ± 2.85kg body weight (BW)] were allocated in individual metabolic cages for 20-day adaptation followed by 6days for measuring dry matter intake (DMI) and CH(4) emission. All lambs received water, mineral supplement, and Cynodon dactylon v. coast-cross hay ad libitum. The treatments consisted of soybean meal (710g/kg) and ground corn (290g/kg) [control (CON)]; soybean meal (150g/kg), ground corn (30g/kg), and Leucaena hay (820g/kg) (LEU); soybean meal (160g/kg), ground corn (150g/kg), and Mucuna hay (690g/kg) (STA); and soybean meal (280g/kg), ground corn (190g/kg), and Mimosa hay (530g/kg) (MIM); all calculated to provide 40g/kg CT (except for CON). DMI (in grams of DMI per kilogram BW per day) was lower for LEU (22.0) than CON (29.3), STA (31.2), and MIM (31.6). The LEU group showed emission of 7.8g CH(4)/day, significantly lower than CON (10.5g CH(4)/day), STA (10.4g CH(4)/day), and MIM (11.3g CH(4)/day). However, when the CH(4) emission per DMI was considered, there were no significant differences among treatments (0.37, 0.36, 0.33, and 0.35g CH(4)/g DMI/kg BW/day, respectively, for CON, LEU, STA, and MIM). The sheep receiving STA had shown a tendency (p = 0.15) to reduce methane emission when compared to the CON group. Therefore, it is suggested that tropical tanniniferous legumes may have potential to reduce CH(4) emission in sheep, but more research is warranted to confirm these results.

Changes in heat production by sheep of Guirra breed after increase in quantity of barley grain on the diet

The heat production (HP) from CH4 and CO2 production and O2 consumption was determined by the respirometry quotient (RQ) method and by C–N balance measurements (CN method). Twelve dry and none pregnant Guirras sheep were fed with 3 diets consisting in the same quantity of alfalfa hay (2kg/d offered) and increasing quantities of barley grain (150, 300 and 450g/d). The experimental design was completely random with 4 replication by treatment. Fasting HP was determinate in one sheep from each group. Ewes were allocated to individual metabolism cages at thermoneutrality. After 10d of adaptation, feed intake, and total fecal and urine output were recorded daily for each ewe during a 5d period, as well as BW at the beginning and end of the period. Gas exchange measurements were recorded by open-circuit face mask respirometry system. Average HP measured by RQ method was in agreement with the average HP determined by CN method accounting for 395.6 and 393.4kJ/kg0.75BW/d, respectively. The metabolizable energy requirement for maintenance (MEm) was estimated by linear regression at 352.3kJ/kg0.75BW.

The genetic deletion of Mas abolishes salt induced hypertension in mice

The G protein-coupled receptor Mas is a physiological antagonist of the angiotensin II type 1 receptor and is associated with angiotensin-(1–7) signaling. We investigated the effect of Mas-deficiency on blood pressure regulation under physiological conditions and salt load using radiotelemetry. Mas-knockout mice and their wild-type controls received a telemetry implant in the carotid artery. One week after surgery, animals were monitored for 3 days receiving normal diet (0.6% NaCl) followed by one-week high-salt diet (8% NaCl). Under same high-salt diet, another set of mice was placed in individual metabolic cages for 4 days. Basal mean arterial pressure, heart rate and locomotor activity displayed normal day–night rhythm in Mas-deficient mice. Mas-knockout mice were normotensive. High dietary NaCl ingestion did not alter heart rate or locomotor activity in both groups, but significantly increased night time mean arterial pressure in control mice whereas this increase was blunted in Mas-deficient mice. Baseline food and water intake and urine osmolality were not different between both genotypes. Under high-salt diet, water consumption and food intake were equally increased in wild-type controls and Mas-knockout, but urinary electrolytes and osmolality were significantly higher in Mas-knockout. Taken together, basal hemodynamic parameters are unchanged in Mas-knockout mice. In contrast to wild-type controls, telemetric mean arterial pressure measurement revealed salt resistance in Mas-deficient animals, probably due to their higher urinary NaCl excretion. This is the first direct proof that Mas blockade might be a new option in the treatment of salt-sensitive hypertension.

Respostas fisiológicas e de desempenho de leitões suplementados com B-glucanos e desafiados imunologicamente

O estudo buscou avaliar as respostas fisiológicas e de desempenho à adição de diferentes níveis de β-glucanos na dieta de leitões recém-desmamados. Foram utilizados 30 machos de linhagem comercial, com 34 dias de idade e peso de 10,9±0,63kg, alojados em gaiolas individuais, durante 14 dias. Os tratamentos variaram somente nos níveis de β-glucanos que foram de 35, 70, 140 e 280g/T. No final desse período, em metade dos animais foram injetados 2,7mg de lipopolissacarídeo (LPS) em 1mL de solução (PBS)/leitão, e nos demais 1mL/leitão de PBS. Foram avaliadas temperatura retal (TR), frequência respiratória (FR), perfil bioquímico sanguíneo e sinais clínicos aos 30, 90, 120 e 390 minutos seguintes à injeção. As respostas de desempenho não foram afetadas pelos níveis de β-glucanos. Foi observado o aumento de TR, tanto em função do LPS como em função da hora em que a temperatura foi medida. No entanto, os animais LPS-injetados, que receberam 280g/T de β-glucanos, tiveram a mesma TR daqueles LPS-não injetados. Os sinais clínicos foram compatíveis com um quadro de inflamação aguda e foram observados, nos animais LPS-injetados, vômito, prostração e diarreia, sendo que a inclusão de β-glucanos não conseguiu reverter esses sintomas. O uso de β-glucanos por 14 dias na dieta de leitões recém-desmamados mostrou um efeito anti-inflamatório em situação de desafio agudo. Para reverter o desafio imunológico utilizado, o nível de 280g/T de β-glucanos mostrou-se o mais recomendado.

Consumo e digestibilidade aparente de dietas com diferentes níveis de inclusão de torta de coco para alimentação de ovinos

The study was conducted at the Universidade Federal da Amazônia to evaluate apparent digestibility and intake for sheep fed diets containing different inclusion levels of fresh coconut meal (25, 50 and 75%). A total of 12 male Santa Inês sheep were used, with a mean age of 5 months and average weight of 19.5 kg, kept in individual metabolic cages distributed in a completely randomized design. Dry matter intake decreased with the inclusion of coconut meal, with values of 699, 405 and 373 g, and 3.67, 2.15 and 2.00% body weight at levels of 25, 50 and 75%, respectively. The same behavior was observed for protein intake; however, no significant differences in intake were observed for values of NDF, ADF and ether extract. Apparent digestibility was reduced (p < 0.05) in the coefficients for treatment with 75% inclusion of coconut meal for dry matter, protein, NDF and ADF, compared to the 25% and 50% treatments. It was concluded that the inclusion of coconut meal in the diet negatively affects the intake and digestibility of fibrous constituents, resulting from high levels of lipids present in the coconut meal

Juazeiro hay in diets of Morada Nova sheep

This study evaluated intake and apparent digestibility of the nutrients in the diet of Morada Nova sheep that received diets containing increasing levels of juazeiro hay in substitution of Tifton 85 bermudagrass hay (0, 33, 67 and 100%). Sixteen non castrated male sheep, weighing an average of 26.75 kg, were used, placed in individual metabolic cages and distributed in a completely randomized block design with four treatments and four replications. Intakes of dry matter, organic matter, crude protein, ether extract, neutral detergent fiber, total carbohydrates, fibrous carbohydrates and non-fibrous carbohydrates and total digestible nutrients were not influenced by the addition of juazeiro hay to the diets, with mean values of 1,042.78 and 595.59 g/day of dry matter and neutral detergent fiber intake, respectively. Linear reduction was observed for digestibility of the dry matter, organic matter, neutral detergent fiber and fibrous carbohydrates. Quadratic reduction was observed for the acid detergent fiber digestibility coefficient. The digestibility coefficients of the crude protein, ether extract, total carbohydrates and fibrous carbohydrates were not significant. The nitrogen balance was not influenced and was positive for all the treatments. The inclusion of juazeiro hay did not influence nutrient intake or nitrogen balance, but reduced the digestibility coefficient of some diet components.

Effects of training and nitric oxide on diabetic nephropathy progression in type I diabetic rats

The aim of the paper is to assess nitric oxide (NO) production during aerobic training and its role on the progression of diabetic nephropathy in rats. Induction of diabetes mellitus (DM) was achieved in adult male Wistar rats with streptozotocin. Half of the animals underwent training on a treadmill and the others (sedentary) stayed on a turned-off treadmill for the same period according to the following groups: sedentary control (CTL + SE); training control (CTL + EX); sedentary diabetic (DM + SE); and training diabetic (DM + EX) (n = 9 for all groups). The training on treadmill was carried out at a work rate of 16 m/min, 60 min/d, 5 d/week for eight weeks. Before and after the exercises, rats were placed in individual metabolic cages with standard chow and water ad libitum, for 24-h urine collection, followed by three hours' fasting blood sample withdrawal from the retro-orbital plexus, under anesthesia. Diabetic animals showed reduction of body weight, creatinine and urea depurations and NO excretion, increased blood glucose concentrations, albuminuria and thiobarbituric acid reactive substance (TBARS) excretion, when compared with the respective controls. All these alterations induced by DM were attenuated in the DM + EX versus DM + SE group. Analysis of insulin concentrations at the end of the protocol showed no significant change between the DM + SE and DM + EX groups. In conclusion, our data show that a routine physical exercise resulted in a better control of glycemia with an increased NO bioavailability and oxidative stress control, associated with an amelioration of renal function. We suggest aerobic training and the control of oxidative and nitrosative stress as useful non-pharmacological tools to delay the progression of diabetic nephropathy.

Efecto diurético de los extractos acuosos y secos de caesalpinia bahamensis lam (brasilete) en ratas wistar

Caesalpinia bahamensis ha sido informada por su uso tradicional como planta diurética, sin embargo, en las bases de datos revisadas no se informan estudios farmacológicos que corroboren esta actividad. Por este motivo se evaluó el efecto diurético de los extractos acuosos y secos de la planta. Para el estudio se utilizaron 30 ratas Wistar hembras entre 165 – 200 g que se dividieron en seis grupos iguales, dos grupos controles y cuatro grupos muestra. Para determinar el efecto diurético se utilizó la prueba de jaulas metabólicas individuales midiendo el volumen de orina por hora y para el procesamiento de los resultados se aplicó el test de ANOVA y de Student – Newman – Keus usando el paquete estadístico PRIMER. Los valores obtenidos en el pico máximo de diuresis para cada grupo fueron: furosemida (4,40 ± 0,59); solución fisiológica (1,45 ± 0,34); extracto secado en baño de vapor (3,12 ± 0,59) y por atomización (4,00 ± 1,19); extracto acuoso obtenido por decocción (3,20 ± 0,63) y por maceración (3,30 ± 0,74). Los grupos controles tienen su máximo pico de actividad en la primera hora después de la administración, mientras que las muestras evaluadas lo manifiestan a la segunda hora, no obstante, no se encontraron diferencias significativas (p&lt;0.05) en la actividad biológica de las muestras y la Furosemida. Se demuestra que los extractos evaluados de Caesalpinia bahamensis tienen un efecto diurético marcado alcanzando su máximo efecto a las dos horas después de administrados

Escherichia coli translocation in experimental short bowel syndrome: probiotic supplementation and detection by polymerase chain reaction

After massive bowel resection, bacterial overgrowth is frequent and favors the occurrence of Gram-negative intestinal bacterial translocation (BT). Probiotics have been recommended in several diseases and may also have beneficial effects on BT. Conversely, polymerase chain reaction (PCR) technique has shown better sensitivity than conventional methods in bacterial detection and has not been investigated in experimental models of short bowel syndrome and BT. To test the hypothesis that Bifidobacterium lactis (BL) administration decreases Escherichia coli bacterial translocation (ECBT) in experimental short bowel syndrome and to confirm the better sensitivity of PCR technique to detect ECBT. Forty-eight adult Wistar rats, orally fed with standard rat chow and tap water ad libitum, were maintained in individual metabolic cages for 10days and divided into three groups: Control group (n=15): non-manipulated animals. RES group (n=15): 80% gut resection. 1ml of sterile water was administered daily after orogastric intubation. RES-PRO group (n=18): same resection as RES group and daily administration of 7.8×10(9) BL (CFU). At the end of the study, portal blood, peripheral blood and mesenteric lymph node (MLN) samples were recovered and cultured. Also, genomic DNA from E. coli was detected by PCR technique. In conventional culture there was no ECBT in control animals whereas 73% of RES and 33% of RES-PRO animals showed it. PCR detected ECBT in 47, 87 and 33%, respectively, showing higher sensitivity.

The effect of previous exposure to dietary microbial phytase on the endogenous excretions of energy, nitrogen and minerals from turkeys

1. A precision feeding experiment was conducted with turkeys, which had previously been fed diets with or without phytase, to study the effects on the excretions of endogenous energy (EEL), nitrogen (ENL), amino acids (EAAL) and minerals. 2. Female turkeys (BUT 6) which had been fed one of 4 experimental diets (low P maize-soya diets (control, C), C + 250 international units of phytase/kg diet (FTU), C + 500 FTU and C + 2500 FTU) were used in this study. All birds were fasted and then given 50 mL of glucose solution at 46 d of age. Birds were allocated to individual metabolism cages in a randomised block design with 8 replicates for each of the 4 previously-fed diets. 3. The response of EEL and ENL to phytase pre-exposure was linear. An increase of 100 FTU reduced the EEL and ENL by approximately 1·6 kJ and 20 mg respectively. The results suggest that a minimum activity of phytase of 500 FTU is needed to initiate the reduction of these losses. 4. Pre-exposure to phytase reduced the EAAL, which was best described as a linear response with increasing phytase dose in the pre-study period. An increase of 100 FTU reduced the losses of total endogenous amino acids by approximately 225 mg. 5. In contrast to the results for endogenous energy losses, turkeys pre-exposed to phytase linearly increased their excretions of Ca and Mg with increasing phytase activity in the pre-study period. 6. The effects of feeding turkeys with supplementary phytase continued for at least 4 d after the diets were withdrawn. This suggests that exposure to phytase alters the functionality and secretions of the gastrointestinal tract, which may influence the nutritive value of diets fed immediately after.

Salt and Nitric Oxide Inhibition Induced Hypertension: The Role of Prostacycline and 8-Isoprostane

Renal prostacycline (PGI2) and oxidative stress are known to be important factors that effect the natriurezis and diuresis. 8-iso prostaglandin F2α± (8-isoprostane), a member of F2-isoprostanes, is formed from the nonenzymatic reaction of arachidonic acid and oxygen radicals in vivo and in vitro, and also it is a marker of oxidative stress in vivo. The aim of this study is to determine the role of renal PGI2 and 8-isoprostane in a salt and nitric oxide (NO) inhibition-induced hypertension model. Rats were distributed equally among four groups (n = 6 per group). Control rats were given normal salt diet (0.32%); high-salt (HS) rats were given high salt diet (3.2%); NG-nitro-L-arginine (L-NNA) rats were given normal salt diet and 25 mg/kg L-NNA; HS+L-NNA rats were given high salt diet and 25 mg/kg L-NNA. Rats were placed in individual metabolic cages for 17 days. Systolic blood pressure (SBP) was measured at days initial, 7th and 14th .Urinary 8-isoprostane and PGI2 levels were analyzed. Salt- loading alone did not change SBP values. The average SBP in L-NNA and HS+L-NNA groups were shown to significantly enhance compared to initial and day 7th in the same groups, respectively. The levels of 8-isoprostane in the HS+L-NNA group was significantly enhanced compared to the other groups. L-NNA or HS diet alone did not change the levels of 8-isoprostane compared to the control group. L-NNA alone did not change PGI2 levels in urine compared to the control. PGI2 levels in the HS, and the HS+L-NNA group was significantly higher compared to the control group. This study concluded that NOS inhibition plus salt-loading induced oxidative stress and increased renal PGI2. Also, it is suggested that augmented oxidative stress may aggravate the hypertension. But the renal synthesis of PGI2 is increased in order to augment the diuresis and natriuresis without the effect of blood pressure (BP).

Effect of the dietary oregano ( Origanum vulgare) on Cu and Zn balance in weaned piglets

A 4-week study conducted on 20 weaned piglets (average initial weight 15 kg) evaluated the effects of dietary oregano ( Origanum vulgare) used in the presence/absence of phytase on the Cu and Zn balance, while reducing/eliminating their inclusion in the diet as inorganic salts. Oregano was harvested from the wild flora. The Cu and Zn concentrations that were taken into consideration (9.85 ppm and 53.31 pmm, respectively) were the consensus values obtained in an interlaboratory study. The piglets were assigned to 4 groups (C, E1, E2, E3), housed in individual metabolic cages and fed on corn–soybean meal-based diets. The diet of the control group (C) with addition of 1% inorganic mineral premix (MP), contained: 40.92 ppm Cu, 144.96 ppm Zn. The experimental diets differed from the C diet as follows: E1 – 3% oregano, 0% phytase (5000 PU/g), 0% MP; E2 – 3% oregano, 0.01% phytase, 0% MP; E3 – 3% oregano, 0% phytase, 0.5% MP, E4 – 3% oregano, 0.01% phytase, 0,5% premix. For groups E1, E2, E3 and E4, 0.5% Zn of the MP were included in the diet, because the dietary oregano amount did not meet the requirements (NRC) for piglets. The mineral balance was determined during 3 periods of 5 days each. The levels of Cu and Zn were measured by FAAS in the samples (weekly samples/piglet) of ingesta, faeces and urine. It was noticed that although the dietary Cu ingested by the groups without MP was 75% (10.08 ppm) lower than C, the absorption coefficients were only 47% (28.83) lower than for group C (54.22%), while in the groups with 0.5% MP, the absorption was just 10% (48.86%) lower than for group C. For Zn, where the amount ingested by the experimental groups was 33% (97.62 ppm) lower than for group C, the absorption coefficients were just 20% (46.3%) lower than for group C (57.64%). No significant differences were noticed for Cu and Zn in terms of apparent absorption, between the groups with/without phytase. The deposits of Cu and Zn in the main organs and serum (from slaughtered piglets) were also evaluated.

Effects of high fibre and low protein diets on performance, digestibility, nitrogen excretion and ammonia emission in the heavy pig

An experiment was conducted to determine the effects of dietary fibre and protein contents and addition of bentonite on performance, nitrogen (N) balance and ammonia emission of heavy pigs from 80 to 170 kg bodyweight. Pigs were fed 4 diets differing in the contents (g/kg as fed) of neutral detergent fibre (aNDFom) and crude protein (CP): 114 and 120 (diet C, control), 193 and 122 (diet HF, high fibre), 176 and 98 (diet HFLP, high fibre and low protein), and 175 and 99 (diet HFLPB, high fibre and low protein plus 10 g bentonite/kg) for aNDFom and CP, respectively. Eighty pigs were randomly allotted to the 4 dietary treatments (4 pens for each treatment and 5 pigs per pen). In addition, 6 pigs from each treatment were placed in individual metabolic cages for 7 days to determine total tract apparent digestibility (TTAD), N balance and ammonia emission from slurry. Dietary treatment did not affect average daily gain, feed conversion ratio and slaughter performance. The inclusion of fibre reduced TTAD of dry matter (P<0.001), organic matter (P<0.001), CP (P=0.026) and energy (P<0.001). Pigs fed the high fibre diets excreted more N in faeces than pigs fed the C diet (P=0.015). Urinary N was lower (P=0.007) for the low protein diets (17.8 g/day, for both) compared to C (25.8 g/day) and HF diets (23.8 g/day). Nitrogen excretion was reduced by approximately 8.0% for each 10 g/kg of dietary CP reduction. The pH values of slurries were not affected by diet. At the end of the monitoring period (14 days) pH was lower (P=0.046) for the low protein diets (8.26 for HFLP; 8.28 for HFLPB) in comparison with the C diet (8.82). Ammonia cumulative emission measured for 14 days was not affected by diet. Significant differences (P=0.048) were observed between diets C vs HF, HFLP and HFLPB when emission was expressed as the ratio between ammonia N emitted and initial N. It is concluded that increasing the fibre content of the diet together with a decrease of the protein content reduced N excretion without jeopardizing performance of heavy pigs. The inclusion of bentonite did not affect any of the traits studied.

The influence of the grape pomace on the ruminal parameters of sheep

To overcome an animal feed shortage in Iran, the effect of replacing alfalfa with grape ( Vitis vinifera sp.) by-product plus polyethylene glycol (PEG, MW 6000) on the ruminal parameters and retained nitrogen (Nr) of sheep was assessed. In a change-over design experiment 6 sheep with similar live weight (61.8 kg), were used during 3 periods of 28 days. The three dietary treatments, which were iso-caloric and iso-nitrogenous, were; control (alfalfa hay, barley grain, wheat chaff, wheat straw), GP diet (grape pomace, barley grain, wheat chaff and urea) and GP diet + PEG. PEG was used to deactivate tannins in grape pomace. Animals were held in individual metabolism cages. They were adapted to experimental conditions for 21 days, before the commencement of the measurement periods. In each period, the digestibilities of organic matter (OMD), NDF (NDFD), crude protein (CPD) and ruminal parameters (pH, ammonia, bacteria and protozoa population), microbial protein synthesis using urinary purine derivatives and N metabolism in sheep were measured. The concentration of OMD, NDFD and CPD was decreased using grape pomace and the addition of PEG only, improved CPD. The amount of endogenous fecal nitrogen loss and Nr in GP diet were less than control ( P < 0.05), these amounts were increased by the addition of PEG ( P < 0.05). GP diet caused reduction in ruminal parameters (pH, ammonia, cellulolytic and proteolytic bacteria population and protozoa number) and microbial protein yield as compared to the control. The addition of PEG increased those parameters ( P < 0.05). In conclusion, GP diet had a detrimental effect on the rumen parameters and Nr with positive influences of PEG addition on most of these parameters.

Effect of dry- versus wet-autoclaving of spray-dried egg albumen compared with casein as protein sources on apparent nitrogen and energy balance, plasma urea nitrogen and glucose concentrations, and growth performance of neonatal swine1

Forty crossbred neonatal pigs with an average initial age of 4 d and BW of 2.16 kg were used in a 28-d experiment to evaluate the nutritional effects of autoclaving a commercial sugar-free, spray-dried egg albumen (EA) compared with casein. Basal diet protein sources were lactic acid casein and EA. Two more dietary treatments were made by replacing the EA with dry-autoclaved EA (DAEA) or wet-autoclaved EA (WAEA, EA and water mixed in a 1.0:1.2 ratio before autoclaving). The DAEA and WAEA were autoclaved at 121 degrees C and 1.75 kg/cm(2) pressure for 30 min, and WAEA was oven-dried after autoclaving. Analyzed trypsin inhibitor units/mg of EA, DAEA, and WAEA were 535.0, 9.0, and 6.5, respectively. Pigs were fed the diets in gruel form to appetite in individual metabolism cages every 2 h during the experiment. Blood samples were taken on d 7, 14, and 21, and total urine and fecal grab-samples were collected from d 14 to 21 of the experiment. Response criteria were N and energy balance, plasma urea N (PUN) and glucose concentrations, and growth performance. The WAEA was a higher quality protein source for neonatal pigs than DAEA. Pigs fed the diet containing WAEA absorbed and retained more (P < 0.05) grams of N/d, had higher (P < 0.05) percentages of N and energy that were absorbed and retained/intake, had lower (P < 0.05) concentrations of PUN overall, and had higher (P < 0.05) ADG and G:F than pigs fed the diet containing DAEA. Most response criteria of pigs fed the diets containing DAEA or EA were not different, although pigs fed the diet containing DAEA had lower (P < 0.05) overall PUN concentrations, and pigs fed the diet containing EA had higher (P < 0.05) percentages of energy absorbed and retained/intake, and higher ADG and G:F than pigs fed the diet containing DAEA. Growth performance was not different for pigs fed the diets containing WAEA or casein. However, pigs fed the diet containing casein excreted less (P < 0.05) fecal N, retained more (P < 0/05) grams of N/d, had higher percentages of N absorbed and retained/intake, and had lower (P < 0.05) PUN concentrations overall than pigs fed the diet containing WAEA. In conclusion, WAEA was a higher quality protein source for neonatal pigs than DAEA or EA, whereas lactic casein was a higher quality protein source for neonatal pigs than EA, DAEA, or WAEA.

Sodium and water handling after gastric bypass surgery in a rat model

Background It was the aim to investigate the influence of gastric bypass on renal sodium and water handling. The relationship between sodium and water absorption along the gastrointestinal tract and their renal excretion is poorly understood. Beneficial effects on blood pressure have been seen after bariatric surgery before significant weight loss has occurred. Methods Male Wistar rats (348 ± 19 g) underwent either gastric bypass (n = 14) or sham operation (n = 7) and were given a low-sodium diet with deionized water ad libitum. Before and after surgery, the rats received an oral sodium load (1.5 mmol/kg) as hyperosmolar saline (616 mM), and were then placed in individual metabolic cages so the urine volume, sodium content, and water intake for 8 hours could be recorded. The urine sodium concentration was also measured. Results The rats that had undergone gastric bypass had a significantly lower body weight than the sham-operated controls throughout the follow-up period (346 ± 21 g versus 501.3 ± 8.0 g at day 60; P = .0004). An oral sodium load after gastric bypass led to an increase in water intake (.07 ± .01 mL/g versus .03 ± .01 mL/g; P = .023), urine output (.03 ± .01 mL/g versus .02 ± .002 mL/g; P = .027), and sodium excretion (65.99 ± 10.7 mol versus 31.71 ± 8.7 mol; P = .020). No change was seen in water intake, urine output, or sodium excretion after sham surgery. Conclusion Urine output, water intake, and sodium excretion are all increased after gastric bypass surgery in rats given an oral sodium load compared with sham-operated controls. More rapid excretion, and less retention, of a dietary sodium load could be a part of the mechanism underlying the beneficial effect of bariatric surgery on blood pressure.

동계사료작물과 혼파한 총체보리 Silage 급여가 흑염소의 사료섭취량, 영양소 소화율 및 혈액성상에 미치는 영향

본 연구는 동계사료 작물과 혼파한 총체보리사일리지를 흑염소에 급여하였을 때, 사료섭취량, 일당증체량, 영양소 소화율 및 질소 축적율에 미치는 영향을 조사하여 흑염소에 대한 혼파 총체보리의 사료가치 평가 자료로 활용하는 데 목적을 두고 실시하였다. 공시가축은 흑염소 12두 (male)를 4처리구 {총체보리 단파 사일리지 첨가구 (T1), 헤어리베치 혼파 사일리지 첨가구 (T2), 사료용 완두 (forage pea) 혼파 사일리지 첨가구 (T3) 및 이탈리안 라이그라스 혼파사일리지 첨가구 (T4)}로 나누어 처리구당 3두씩 개체별 대사케이지에 라틴방각법으로 실시하였으며 그 결과는 다음과 같다. 1일 두당 건물과 유기물 섭취량은 IRG 혼파 사일리지 첨가구가 총체보리 단파 및 사료용 완두 혼파 사일리지 첨가구보다 유의하게 높았으며 (p<0.05), 조단백질 섭취량도 IRG 혼파 사일리지 첨가구가 가장 높았다 (p<0.05). ADF와 NDF 섭취량은 IRG > HV > 총체보리 단파 > 사료용 완두 혼파 사일리지 첨가구 순으로 나타났다. 일당증 체량은 IRG와 HV 혼파 사일리지 첨가구가 총체보리 단파와 사료용 완두 혼파 사일리지 첨가구보다 유의하게 높게 나타났다 (p<0.05). 건물과 유기물 소화율은 HV와 IRG 혼파 사일리지 첨가구가 사료용 완두 혼파와 총체보리 단파 사일리지 첨가구보다 유의하게 높게 나타났다 (p<0.05). 조단백질 소화율은 총체보리 단파사일리지 첨가구가 HV와 IRG 혼파 사일리지 첨가구보다 유의하게 낮게 나타났다 (p<0.05). 질소섭취량은 HV와 IRG 혼파 사일리지 첨가구가 사료용 완두 혼파 사일리지 첨가구보다 유의하게 높게 나타났다 (p<0.05). 이러한 결과를 종합적으로 고려할 때 총체보리와 헤어리베치 혹은 이탈리안 라이그라스 혼파 사일리지 첨가가 사료섭취량, 영양소 소화율 및 질소 축적율 증가로 인해 흑염소의 생산성이 높은 것으로 판단된다. This experiment was carried out to estimate the nutritive value of mixed-sowing winter forage crop and whole crop barley by investigating the effects of feeding mixed-sowing winter forage crop and whole crop barley in KBG (Korean black goat) on feed intake, average daily body weight gain, nutrient digestibility and nitrogen retention. The 12 male KBG were divided into four experimental groups - i.e. T1: barley silage added group, T2: mixed-sowing hairy vetch silage added group, T3: mixed-sowing field peas added silage, T4: mixed-sowing Italian rye grass added silage group. Three KBG per each treatment were allotted into individual metabolic cages by Latin-square design. The results from this study are as follow. The DMI (dry matter intake) and organic matter intake in T4 were significantly (p<0.05) higher than those in T1 and T3 and crude protein intake in T4 also recorded the highest among treatments (p<0.05). The highest values in intakes of ADF and NDF were observed in T4 followed by T2, T1 and T3 in order. The average daily body weight gains in T4 and T2 were significantly (p<0.05) higher than those in TI and T3. The dry and organic matter digestibility in T2 and T4 were significantly (p<0.05) higher than those in T1 and T3. The crude protein digestibility in T1 was significantly (p<0.05) lower than those in T2 and T4. The nitrogen intakes in T2 and T4 were significantly (p<0.05) higher than those in T3. The results obtained from this study suggested that the feeds supplemented with whole crop barley with hairy vetch and Italian rye grass mixture silage increased KBG productivity resulted from increases in feed intake, nutrient digestibility and nitrogen retention.

Separate and overlapping metabolic functions of LXRα and LXRβ in C57Bl/6 female mice

The two liver X receptors (LXRs), LXRalpha and LXRbeta, are transcriptional regulators of cholesterol, lipid, and glucose metabolism and are both activated by oxysterols. Impaired metabolism is linked with obesity, insulin resistance, and type 2-diabetes (T2D). In the present study, we aimed to delineate the specific roles of LXRalpha and -beta in metabolic processes. C57Bl/6 female mice were fed a normal or a high-fat diet (HFD) and metabolic responses in wild-type, LXRalpha(-/-), LXRbeta(-/-), and LXRalphabeta(-/-) mice were analyzed. Whole body fat and intramyocellular lipid contents were measured by nuclear magnetic resonance. Energy expenditure was measured in individual metabolic cages. Glucose, insulin, and pyruvate tolerance tests were performed and gene expression profiles analyzed by qPCR. We found that both LXRbeta(-/-) and LXRalphabeta(-/-) mice are resistant to HFD-induced obesity independently of the presence of high cholesterol. Using tolerance tests, we found that, on an HFD, LXRbeta(-/-) mice enhanced their endogenous glucose production and became highly insulin resistant, whereas LXRalpha(-/-) and LXRalphabeta(-/-) mice remained glucose tolerant and insulin sensitive. Gene expression profiling confirmed that LXRbeta is the regulator of lipogenic genes in visceral white adipose tissue (WAT) and muscle tissue and, surprisingly, that Ucp1 and Dio2 are not responsible for the protection against diet-induced obesity observed in LXRbeta(-/-) and LXRalphabeta(-/-) mice. LXRalpha is required for the control of cholesterol metabolism in the liver, while LXRbeta appears to be a major regulator of glucose homeostasis and energy utilization and of fat storage in muscle and WAT. We conclude that selective LXRbeta agonists would be novel pharmaceuticals in the treatment of T2D.

Previous exposure to dietary phytase reduces the endogenous energy losses from precision-fed chickens

1. A precision feeding experiment was conducted with broiler chickens, which were previously fed on diets with or without phytase, to study the effects of previous exposure to dietary phytase supplementation on the excretions of endogenous energy, nitrogen, amino acids and minerals. 2. Female Ross 308 broiler chickens, which had previously received one of 4 experimental diets (low P maize/soy diets (control, D), D + 250 international units of phytase per kg diet (FTU), D + 500 FTU and D + 2500 FTU) were used in the study. All birds were starved and then given 50 ml of glucose solution at 44 d of age. The birds were allocated to individual metabolism cages in a randomised block design with 8 replicates of each of the 4 dietary treatments. 3. Chickens which had been previously fed on diets supplemented with phytase excreted 32% less energy and 28% less dry matter per kg metabolic body weight (W0⋅75) from endogenous sources, compared to birds fed the unsupplemented diet. 4. Birds previously given phytase supplemented diets excreted 60% less sodium than those given the control diet, but there was no effect on all other minerals investigated. There was no effect of diet on the excretion of endogenous N, sialic acid or amino acids. 5. The results showed that the effects of feeding chickens on diets with supplementary phytase may continue for a few days after the diets are withdrawn. This suggests that previous exposure to phytase may alter the nutritive value of follow-on diets, which may be a commercially important effect.

Nocturnal urinary melatonin levels and urine biochemistry in microwave-irradiated rats

The aim of this study was to explore whether, during the course of a 15 days-lasting experiment, a two hours per day and five days per week, 2.45 GHz microwave whole-body irradiation may substantially and therefore provably affect rats’ nocturnal urinary 6-hydroxy-melatonin sulphate (aMT6s) excretion and urinalysis parameters. The average whole-body specific absorption rate (SAR) equalled to 1.25 (± 0.36 SE) W/kg. To collect nocturnal urine samples, animals were held in individual metabolic cages every experimental night from 7:00 PM till 7:00 AM next day. The concentration of aMT6s in rat urine samples was determined by a direct radioimmunoassay. Bilirubin, ketones, and urine protein content have been determined via multiple-use reagent strips. In comparison to the sham-exposed group, no significant changes in body temperature and food or water intake were observed in the exposed group. A decline in aMT6s, determined in the exposed rats, was observed from day 8 to day 11 of the experiment (P < 0.05). The aMT6s level remained consistently low until the end of the experiment, but not significantly lower than the control values. The results of the urine samples biochemical workup failed to reveal any significant differences between the exposed and the control animal groups. The results of this study suggest that, under the above described experimental conditions, repeated 2.45 GHz irradiation could act as a stressor and therefore influence the melatonine balance in rat.