Plasma Urea Concentrations Research Articles

Sublethal, sex-specific, osmotic, and metabolic impairments in embryonic and adult round stingrays from a location exposed to environmental contamination in southern California, USA

Organic contaminants are known to affect a suite of physiological processes across vertebrate clades. However, despite their ancient lineage and important roles in maintaining healthy ecosystems, elasmobranchs (sharks, skates, and rays) are understudied with regard to sublethal effects of contaminant exposure on metabolic processes. Perturbations resulting from contaminant exposure can divert energy away from maintaining physiological homeostasis, particularly during energetically challenging life stages, such as pregnancy and embryonic development. Using the round stingray (Urobatis halleri) as a model elasmobranch species, we captured adult males and pregnant females (matrotrophic histotrophy) and their embryos from two populations differing in their environmental exposure to organic contaminants (primarily polychlorinated biphenyls (PCBs)). Pregnant females from the PCB-exposed population experienced significant decreases from early- to late-pregnancy in tissue mass and quality not seen in reference females. PCB-exposed pregnant females also failed to maintain plasma urea concentrations as pregnancy progressed, which was accompanied by a loss in muscle protein content. Despite the energetic demands of late-term pregnancy, females had significantly greater liver lipid content than reproductively inactive adult males. PCB-exposed adult males also had high metabolic capacity (i.e., enzyme activity) for most substrate groupings of all sex-site groups, suggesting that males may be even more negatively impacted by contaminant exposure than pregnant females. Evidence that in utero exposure to PCBs via maternal offloading impairs embryo outcomes is accumulating. Embryos from the PCB-contaminated site had lower tissue quality measures and indications that sex-based differences were manifesting in utero as males had higher metabolic capacities than females. This study indicates that accumulated PCB contaminants are not physiologically inert in the stingray.

FURTHER STUDIES ON URINARY 3-METHYLHISTIDINE EXCRETION AS AN INDIRECT INDEX OF DIETARY AMINO ACID ADEQUACY IN RATS

As a further step in the determination of the sen­sitivity of urinary 3-methylhistidine (3-MeH) to essential amino acid adequacy in diet, 36 male albino rats of the Wistar strain were divided into six groups +of six rats per group. Each group with an initial .mean live weight of 106.52 ± 0.54g was fed in in­dividual metabolic cages on a basal diet sup­plemented with graded levels of DL-methionine. Total methionine in diet ranged between 0.25 and 1.05%. The study lasted 10 days. The response of urinary 3-methylhistidine excretion to the graded levels of methionine in diet was compared to responses obtained from growth performance characteristics, plasma urea concentration, liver nitrogen and creatinine excretion. With the excep­tion of feed intake, all other indices of dietary pro­tein adequcy and efficient amino acid utilization viz growth rate, protein efficiency ratio, serum urea concentration, and creatinine excretion were significantly (P 0.05) to P 0.01) influenced by dietary methionine level. Maximum growth rate, liver N and urinary 3-methylhistidine were observed. in rats given 0.45% total methionine in diet. Supplementing the basal diet to contain 0.45% total,' methonine significantly (P 0.01) decreased serum urea concentration. Urinary 3-methylhistidlne excre­tion was found by regression analysis to be positively correlated to body weight gain (r = 0.73), feed intake (r = 0.61), urinary creatinine excretion (r = 0.74) and liver N (0.72) but negatively correlated to dietary methionine level (r = —0.41). We suggested that urinary 3-MeH excretion be added to the list of available indicts for dietary amino acid adequacy.

Effect of feeding varying levels of dietary crude protein and digestible energy levels on nitrogen retention, urinary and blood plasma constituents in pigs fed from 9 to 60kg

This study was designed to investigate the effects and possible interactions of varying crude protein (CP) and digestible energy levels (DE) on Nitrogen Retention, (NR), Urinary and blood plasma constituents in pigs reared from 6 to 60 kg liveweight. One hundred and twenty eight Large White x Landrace pigs weighing 9+1.5kg were assigned to sixteen groups of eight pigs, comprising four females and four castrated males in a 4x4 factorial design, the factors were four crude protein levels: (18, 21, 24 and 27%) and four digestible energy levels: (3,000; 3,300: 3,600 and 3,900 kcal/kg) nitrogen retention studies were conducted during the 4 week after the animals were 4 weeks on test diets. There were 6 pigs (3 females and 3 males) in the nitrogen balance trials. Apparent protein digestibility was calculated from the faecal collection. Urinary urea, citrulline and allocation were also determined. Six out of the eight experimental pigs per diet were selected for bleeding and the plasma urea concentrations were determined. There was a significant ( 0.05) Protein x Energy, Energy X Sex and Protein x Energy x Sex interactions. Females retained significantly higher proportions of their nitrogen intake than the castrated males, the lowest nitrogen retention was obtained on the lowest protein and lowest energy combination. The best nitrogen retention in males was obtained on the 21% protein diet with 3,600 kcal DE/kg, while in females; the best was obtained on the diet containing 24% Protein. Total urinary urea concentration was significantly (p 0.01) influenced by both protein and energy levels and significant Protein x Energy interactions also occurred. Dietary protein, expectedly, significantly influenced plasma urea concentrations tending to be lowest on the two intermediate energy levels; 3,300 and 3,600 kcal DE /kg. Nitrogen retention was optimum between 18 and 21% protein levels and castrated males tended to show optimum nitrogen economy on lower protein levels than female pigs. Total urea concentration paralleled nitrogen retention profile. The Kiriyama Index(A/U x IP) may be a precise method to determine protein requirement for pigs in the humid tropical environment. Digestible energy levels of between 3,300 and 3,600 kcal/kg would be adequate for maximum nitrogen economy.

Effects of Dietary N-carbamylglutamate on Growth Performance, Apparent Digestibility, Nitrogen Metabolism and Plasma Metabolites of Fattening Holstein Bulls.

Simple SummaryIt is critical to find an effective and safe feed additive to improve the utilization of nitrogen by ruminants. N-carbamylglutamate (NCG), a structural analogue of N-acetylglutamate, may have the potential to improve the utilization of nitrogen by bulls. Therefore, the effects of adding different levels of NCG on the growth performance, nutrient digestibility, nitrogen metabolism and plasma metabolites of fattening Holstein bulls were investigated in this study. The addition of NCG increased concentrations of plasma Arg, Ile, Val, total essential amino acid and total nonessential amino acid, which in turn resulted in higher N utilization and CP digestibility for growth and, therefore, higher average daily gain in NCG-fed bulls.N-carbamylglutamate (NCG), a structural analog of N-acetylglutamate, improves nitrogen utilization in dairy cows. However, the effects of NCG on bulls are unknown. The purpose of the current research was to investigate the effects of adding different amounts of NCG on growth performance, nutrient digestibility, nitrogen metabolism and plasma metabolites of fattening Holstein bulls. Twenty-four Holstein bulls with similar body weights (BW, 408 ± 21.9 kg) and ages (450 ± 6.1 d; all mean ± SD) were selected for the feeding trial. After 2 weeks of adaptation, bulls were blocked by BW and age and subsequently randomly assigned to 1 of 4 groups: (1) CON group (control diet), (2) L group (supplementation with 20 mg/kg BW NCG), (3) M group (supplementation with 40 mg/kg BW NCG), or (4) H group (supplementation with 80 mg/kg BW NCG). The addition of NCG linearly and quadratically increased the average daily gain (CON vs. L vs. M vs. H = 1.03 vs. 1.19 vs. 1.40 vs. 1.26 kg/d) (p < 0.05), feed conversion ratio (CON vs. L vs. M vs. H = 11.92 vs. 9.22 vs. 7.76 vs. 8.62) (p < 0.05), crude protein digestibility (CON vs. L vs. M vs. H = 64.3 vs. 63.8 vs. 67.7 vs. 65.8%) (0.05 < p < 0.10), N retention (p < 0.05) and N utilization (p < 0.05) of bulls, whereas the contents of fecal N (0.05 < p < 0.10) and urinary N (0.05 < p < 0.10) in NCG-fed bulls linearly decreased compared with those in CON bulls. Bulls fed NCG showed a quadratic increased plasma nitric oxide (p < 0.05) concentration. Furthermore, Arg (p < 0.05), Ile (p < 0.05), Val (p < 0.05), Ala (p < 0.05), Glu (p < 0.05), Ser (p < 0.05), total essential amino acid (p < 0.05) and total nonessential amino acid (p < 0.05) concentrations linearly and quadratically increased with increasing doses of NCG. In contrast, plasma urea (p < 0.05) and ammonia (p < 0.05) concentration linearly and quadratically decreased with increasing doses of NCG. Overall, the addition of NCG increased plasma Arg, Ile, Val, TEAA and TNEAA concentration, which in turn resulted in a higher N utilization and, therefore, higher average daily gain in NCG-fed bulls, providing baseline data for the widespread application of NCG in beef cattle production.

NUTRIENT INTAKE, DIGESTIBILITY AND RUMEN STUDIES IN GOATS FED VARYING LEVELS OF CASSAVA PEELS AND BREWER'S DRIED GRAIN

Dry matter intake, nutrient digestibility and some rumen and blood metabolites were investigated in goats fed five diets composed of cassava peel and brewer's dried grains (BDG) in the ratios of approximately 82:8, 69:20, 57:33, 44:45 and 32:58. Urea and molasses were included in each diet at 2% and 7.5% respectively and the crude protein levels of the diets were approximately 8%, 11%, 14%, 17% and 20%. There were no significant (P &gt; 0.05) differences in Dry matter and Organic matter intake but N intake Increased up to Diet 4. There were dietary effects on the digestibility of DM, N, crude fibre, acid detergent fibre, either extract, nitrogen free extract and energy but not 0M. The highest digestibility values were obtained on diet 4 for most of the nutrients. The concentrations of rumen ammonia and blood plasma urea increased from Diet 1 to Diet 5. There were significant (P &lt; 0.05) dietary effect on rumen fluid ph. Rumen protozoal count increased from Diet 1 to Diet 5. The depression in digestibility of Diet 5 would indicate that BDG should not be included at up to 58% in the diet of goats.

Cardiac Inflammation, Oxidative Stress, Nrf2 Expression, and Coagulation Events in Mice with Experimental Chronic Kidney Disease.

Chronic kidney disease (CKD) is known to be associated with cardiovascular dysfunction. Dietary adenine intake in mice is also known to induce CKD. However, in this experimental model, the mechanisms underlying the cardiotoxicity and coagulation disturbances are not fully understood. Here, we evaluated cardiac inflammation, oxidative stress, DNA damage, and coagulation events in mice with adenine (0.2% w/w in feed for 4 weeks)-induced CKD. Control mice were fed with normal chow for the same duration. Adenine increased water intake, urine output, relative kidney weight, the plasma concentrations of urea and creatinine, and the urinary concentrations of kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin. It also decreased the body weight and creatinine clearance, and caused kidney DNA damage. Renal histological analysis showed tubular dilation and damage and neutrophilic influx. Adenine induced a significant increase in systolic blood pressure and the concentrations of troponin I, tumor necrosis factor-α, and interleukin-1β in heart homogenates. It also augmented the levels of markers of lipid peroxidation measured by malondialdehyde production and 8-isoprostane, as well as the antioxidants superoxide dismutase and catalase. Immunohistochemical analysis of the hearts showed that adenine increased the expression of nuclear factor erythroid-derived 2-like 2 by cardiomyocytes. It also caused cardiac DNA damage. Moreover, compared with the control group, adenine induced a significant increase in the number of circulating platelet and shortened the thrombotic occlusion time in pial arterioles and venules in vivo, and induced a significant reduction in the prothrombin time and activated partial thromboplastin time. In conclusion, the administration of adenine in mice induced CKD-associated cardiac inflammation, oxidative stress, Nrf2 expression, and DNA damage. It also induced prothrombotic events in vivo. Therefore, this model can be satisfactorily used to study the cardiac pathophysiological events in subjects with CKD and the effect of drug treatment thereon.

Moderate over-feeding of different sources of metabolizable energy and protein improved gestational insulin resistance markers and maternal metabolic status of sheep around lambing

The objective of this study was to determine the effect of moderate over-nutrition of energy (using flaxseed as a source of n-3 fatty acids) and protein (using rumen-protected lysine and methionine) around parturition on prepartal insulin resistance (IR) and periparturient metabolic status and performance of ewes. For this purpose, 32 apparently healthy ewes (2.5 ± 1 years old, 42.19 ± 1.65 kg body weight (BW)) were randomly selected out of 200 pregnant Zell ewes on d 50 before the expected lambing. After receiving a ten-day adaptation diet, eight ewes were randomly allocated to one of the following four dietary treatments: 1) the adaptation diet that meets the metabolizable energy (ME) and protein (MP) requirements of ewes during late pregnancy as recommended by National Research Council = NRC (2007) (Control = CON). 2) A diet with 10% higher levels of ME than NRC (2007) recommendations using corn grain as a source of extra ME (HEC). 3) A diet with 10% higher levels of ME compared to NRC (2007) recommendations using flaxseed for additional ME (HEF). 4) A diet with a 10% higher level of MP than NRC (2007) recommendations using rumen-protected lysine and methionine as a source of extra MP (PRO). While the dietary treatments did not affect animals’ dry matter intake (DMI), the CON ewes lost more BW starting from d 10 to d 30 relative to parturition compared to others (P < 0.05). Milk protein and fat yield (g/d) were significantly higher for PRO and HEF compared to HEC and CON ewes (P < 0.05). Moderately over-fed ewes with MP and ME had an improved insulin sensitivity (IS) compared to CON ones. The source of additional ME also impacted IR indices because HEC showed an enhancement in IS than HEF animals (P < 0.05). A lower IS in CON ewes was parallel with higher concentrations of plasma urea at prepartum (P < 0.01), lower levels of plasma cholesterol, triglyceride (P < 0.01) and glucose post-partum (P < 0.05), and a tendency for higher levels of beta-hydroxybutyrate (BHB) and non-esterified fatty acids (NEFA) in CON ewes during both pre- and post-partum periods. There were negative correlations between plasma urea, BHB, and NEFA with IR markers on d 7 prepartum in line with these results. Comparing data, we could not find a significant change in metabolic status among ewes fed with either PRO or HEF/HEC. In conclusion, the inclusion of 10% extra MP and ME could improve late gestation maternal IS and the metabolic status of dams around lambing.

Feedlot performance, carcass characteristics and economic profits in four Holstein-beef crosses compared with pure-bred Holstein cattle

Cross-breeding can be a profitable strategy to improve beef production. The objective of this study was to compare feedlot performance, carcass characteristics, and economic profits between four Holstein-beef crosses and pure-bred Holstein calves. Beef crosses were produced by crossing Holstein (H) cows with Angus (A), Charolais (C), Limousin (L) and INRA 95 (I) bull semen. The performance of 24 calves of each breed (120 calves in total) was compared in an experimental period of 11 months. The average calf age at the start of the experiment was 143, 169, 138, 186, and 133 d for A, I, C, L, and H groups, respectively. The experimental design was repeated-measures split-plot. The animals within each of five breeds (plots) were randomly divided into six pens of four animals each (consisting of half males and half females). The calves received starter, grower and finisher diets for the experimental period. The results indicated that average daily gain was significantly higher in crossbred calves than in pure-bred Holstein calves. The Charolais crossbred calves and pure Holsteins had significantly lower dry matter intake than other hybrids, and, as a result, feed conversion ratio in the C × H calves was remarkably more favorable compared to other groups. Dressing percentage for C × H, L × H and I × H crossbreds was higher than for pure-bred Holstein and the A × H crossbred cattle. The C × H crossbred cattle had significantly higher plasma urea concentrations than did other genetic groups (P < 0.05). However, other blood metabolites did not differ significantly among the groups. Economic calculations demonstrated that the respective highest profit for the whole experimental period belonged to the crossbreds of C × H (44660778 Rials), I × H (35853953 Rials), L × H (32013587 Rials), A × H (25794039 Rials), and pure-bred Holstein cattle (24200274 Rials). Therefore, the hypothesis that the calves from Holstein-beef crosses would have higher economic productivity than pure-bred Holstein calves was substantiated.

Evaluation of peptidylarginine deiminase 4 and PADI4 polymorphisms in sepsis-induced acute kidney injury.

The aim of this study is to evaluate the peptidylarginine deiminase 4 (PAD 4) concentration and PADI4 polymorphisms as predictors of acute kidney injury (AKI) development, the need for renal replacement therapy (RRT), and mortality in patients with septic shock. We included all individuals aged ≥ 18 years, with a diagnosis of septic shock at ICU admission. Blood samples were taken within the first 24 hours of the patient's admission to determine serum PAD4 concentration and its PADI4 polymorphism (rs11203367) and (rs874881). Patients were monitored during their ICU stay and the development of SAKI was evaluated. Among the patients in whom SAKI developed, mortality and the need for RRT were also evaluated. There were 99 patients, 51.5% of whom developed SAKI and of these, 21.5% needed RRT and 80% died in the ICU. There was no difference between PAD4 concentration (p = 0.116) and its polymorphisms rs11203367 (p = 0.910) and rs874881 (p = 0.769) in patients in whom SAKI did or did not develop. However, PAD4 had a positive correlation with plasma urea concentration (r = 0.269 and p = 0.007) and creatinine (r = 0.284 and p = 0.004). The PAD4 concentration and PADI4 polymorphisms were also not associated with RRT and with mortality in patients with SAKI. PAD4 concentration and its polymorphisms were not associated with SAKI development, the need for RRT, or mortality in patients with septic shock. However, PAD4 concentrations were associated with creatinine and urea levels in these patients.

Differences between Holstein dairy cows in renal clearance rate of urea affect milk urea concentration and the relationship between milk urea and urinary nitrogen excretion

Urine and fecal excretions from cattle contribute to global nitrogen (N) emissions. The milk urea nitrogen (MUN) concentration in dairy cows is positively correlated with urinary urea N (UUN) emissions, and both decline with the reduction in crude protein intake. However, MUN concentration may differ between individual cows despite feeding the same ration. Thus, we hypothesized that due to differences in endogenous N utilization cows with high MUN concentration excrete more UUN than cows with a low MUN concentration. The objective of the present study was to elucidate N partitioning and urea metabolism in dairy cows with divergent MUN concentrations fed two planes of crude protein. Twenty Holstein dairy cows with high (HMU; n = 10) and low (LMU; n = 10) milk urea concentrations were fed two isocaloric diets with a low (LP) and normal (NP) crude protein level. Methane and ammonia emissions were recorded in respiration chambers. Feed intake, feces and urine excretions and milk yield were recorded for four days and subsamples were analyzed for total N and N-metabolites. A carbon-13 labeled urea bolus was administered intravenously followed by a series of plasma samplings. Total N and UUN excretions and ammonia emissions from excreta were lower on the LP diet, however, methane emissions, urinary N excretions and ammonia emissions were comparable between groups. Although plasma and salivary urea concentrations, urea pool size and urea turnover were higher, HMU cows had lower renal urea clearance rates. Additionally, HMU cows had lower renal clearance rates for creatinine, uric acid and creatine and excreted less uric acid (on the LP diet only) and creatine with urine. In conclusion, contrary to our hypothesis, HMU cows did not excrete more UUN than LMU cows. The lower urinary creatine excretion of HMU cows suggests that these animals have a lower environmental nitrogen footprint.

EFFECTS OF TYPE 2 DIABETES MELLITUS INDUCTION AND OF MODERATE PHYSICAL EXERCISE ON THE HEPATIC METABOLISM AND OXIDATIVE STRESS IN WISTAR RATS

AIMS: The aim of the study was to verify if the induction of Type 2 Diabetes Mellitus (T2DM) by the association of streptozotocin and high fat diet causes hepatic alterations and if physical exercise can improve these alterations. METHODS: Forty-six Wistar rats were divided into two groups. One group received a diet containing 60% of fat for 9 weeks and on the 14th day they were injected with a single dose of streptozotocin (25mg/kg). The other group, named control group, received a standard diet and a single dose of citrate buffer was given. Animals were them divided into two subgroups: one sedentary (S) and the other submitted to physical exercise (PE), totalizing four groups: C-S; C-PE; HF-S; HF-PE. After euthanasia blood and liver were collected. Plasma and hepatic concentrations of triacylglycerol and very low density lipoprotein; enzyme alanine transaminase, aspartate transaminase and arginase; urea, lactate and 8-isoprostane (an oxidative stress marker) were dosed. RESULTS: Capillary glucose was significantly higher in HF-S and HF-PE group animals compared to C-S and C-PE groups. There were no significant differences in alanine transaminase, arginase, oxidative stress and lactate concentration among the groups. Plasma urea concentration and hepatic aspartate transaminase concentration was lower in HF-S and HF-PE than in C-PE. Concerning liver triacylglycerol and very low density lipoproteins, both were higher in the HF-PE group when compared to the C-S. CONCLUSIONS: We conclude that diet was decisive for the aforementioned parameters alterations and that physical exercise protocol was not efficient to improve analyzed parameters.

Application of sorbitol-based infusion preparation for protein-protecting effect in surgery patients with middle breast cancer

Objective. To study the energy effect of infusions of the drug Sorbilact in the body of operated patients with cancer of the middle thoracic esophagus.&#x0D; Materials and methods. Clinical use of the drug Sorbilact was performed in 30 operated patients with cancer of the middle thoracic esophagus (the main group). Sorbilact was administered intravenously immediately after surgery, drip at a rate of 30 drops per minute for 5 days at a dose of 800 ml per day. Plasma urea concentration was determined before infusions on the 1st day after surgery, and on days 2, 3, 5 after Sorbilact infusions. The control group – 25 operated patients – was administered 5 % glucose solution at a dose of 800.0 ml.&#x0D; Results and discussion. In the first days after surgery in patients with cancer of the middle thoracic esophagus an increase in the concentration of urea in blood plasma was revealed. In the main group of operated patients after resection of the middle thoracic esophagus in repeated studies on the 2nd, 3rd, 5th day after infusions a significant decrease in the concentration of urea in blood plasma was showed. It indicates that less endogenous protein is consumed for energy purposes, and the caloric needs of the operated body are covered by intensive absorption of Sorbilact, which reduces the catabolism of internal proteins, resulting in reduced nitrogen production, which is manifested in a decrease in the concentration of urea in blood plasma and its difference. In the control group of operated patients in repeated studies on the 2nd, 3rd, 5th day after infusions an increase in plasma urea was revealed, which indicates insufficient caloric energy expenditure of the operated organism.&#x0D; Conclusions. Intravenous infusions of the drug Sorbilact according to the indicator of increment of urea in blood plasma in operated patients after resection of the middle thoracic esophagus in the early postoperative period show a pronounced energy effect.

Effects of flaxseed-rich diet on reproductive performance in estrous-synchronized Baluchi ewes.

The purpose of this study was to compare the effects of using different levels of flaxseed in diets on the reproductive performance of estrous-synchronized Baluchi ewes (para 3). Diets contained either basal diet (control) or different levels of extruded flaxseed (2%, 5%, 7%, 10%, and 12%) and were fed from lambing to 60 days after lambing. The ewe estrus cycles were synchronized using controlled internal drug release (CIDR) for 14 days starting from day 16 of fat supplementation. The rams were introduced 24 h after CIDR removal. The ewes fed control diets had the highest mean dry matter intake (1,800&amp;plusmn;35 g) which was declined with the increase of flaxseed levels. The experimental diets exerted no effects of urea concentration in blood plasma. However, plasma glucose concentration was lower (p &amp;lt;0.05) in the ewes fed the control diet and 2% flaxseed, compared to those in other groups. Nonetheless, there was no difference among the ewes fed 5%, 7%, 10%, and 12% flaxseed in terms of plasma glucose concentrations (p &amp;lt;0.05). The ewes fed 2% flaxseed had the highest level of plasma triglyceride concentration among other groups. In addition, the control group had the lowest level of plasma total cholesterol and low-density lipoproteins concentration in comparison to other groups (p &amp;lt;0.05). However, plasma nonesterified fatty acids and &amp;beta;-hydroxybutyrate concentrations were similar among the groups (P&amp;gt;0.05). The mean interval between CIDR removal and the exhibition of estrus ranged from 30 to 40 h with the shortest interval being recorded in the ewes fed 12% flaxseed (p &amp;lt;0.05). The control group had the lowest number of follicles on estrus day among other groups (p &amp;lt;0.05). Furthermore, the ewes fed 10% and 12% flaxseed had the highest ovulation, pregnancy, and lambing rates, compared to other groups (p &amp;lt;0.05). In conclusion, the findings revealed that feeding the ewes with 10% and 12% flaxseed resulted in the improvement of reproductive performance.

Impact of substituting compound feed with increasing levels of fresh grass-clover on nitrogen metabolism and plasma metabolites of sows

The purpose of this study was to identify biomarkers for fresh grass-clover intake and determine the digestibility and energy value of fresh grass to estimate voluntary fresh grass-clover intake in sows kept on pasture according to organic production practice. A total of sixteen multiparous dry sows (Danish Landrace x Danish Yorkshire) were housed in metabolism cages for 2 periods of 5 d. To study dietary effects, sows were fed one of four mixed treatments where increasing proportions of a basal commercial organic sow compound feed was partly replaced with 0, 2, 4, or 6 kg fresh grass-clover collected 3 wk after the previous cut. Sows were fed similar amounts of metabolizable energy (ME). Total collection of urine and feces was performed on a daily basis for 5d, and blood samples were collected from the jugular vein on the last day of feeding. Plasma metabolites were analyzed using a non-targeted liquid chromatography-mass spectrometry (LCMS) approach. Analyzed plasma metabolites (area under the curve in arbitrary units from the LCMS) were screened for correlation with grass intake. Data on nutrient digestibility and plasma metabolites were analyzed using a MIXED procedure while accounting for repeated measurements. Apparent total tract digestibilities of dry matter, organic matter, nitrogen, and energy of fresh grass-clover were 72, 64, 71, and 68%, respectively, using the regression method. The N intake increased linearly with increasing fresh grass-clover intake (P < 0.001). There was no evidence of altered N deposition and N utilization in response to increasing grass intake (P > 0.05). There was a linear increase in plasma urea content (2.64 to 4.39 mM) when grass intake increased from 0 to 6 kg/d (P = 0.02). Plasma glucose, lactate, creatinine and NEFA, and triglycerides were not affected by increased grass-clover intake. The daily ME contribution from fresh grass-clover (MJ/d) was found to be highly positively correlated with plasma pipecolic acid (Y = 0.0289 X; r2 = 0.91; P < 0.001) and a metabolite tentatively identified as plasma bisnorbiotin (Y = 0.482 X; r2 = 0.92; P < 0.001). In conclusion, fresh grass-clover intake of sows was highly correlated with plasma pipecolic acid and plasma bisnorbiotin concentration and apparent total tract digestibility of DM, OM, N, and energy estimated for 100% fresh grass-clover intake in dry sows was 64 to 72% using the regression method.

Performance and immune response of steers Nellore finished in feedlot and fed diets containing dry leaves of Baccharis dracunculifolia

This study was carried out to investigate the effects of addition Baccharis dracunculifolia leaves in nature on animal performance, feed intake, ingestive behavior, and blood parameters of Nellore steers finished in feedlot on high-grain diets. A total of 40 Nellore steers, with an average body weight of 412.9 ± 22.0 kg were distributed in individual pens, equipped with automatic drinkers and masonry feeders. The steers were randomly assigned to one of four studied diets, therefore the CONT – basal diet; BAC05 – basal diet and inclusion of B. dracunculifolia leaves in natura (5 g/animal/day); BAC10 – basal diet and inclusion of B. dracunculifolia leaves in natura (10 g/animal/day); and BAC15 – basal diet and inclusion of B. dracunculifolia leaves in natura (15 g/animal/day). The use of plants in nature did not affect final body weight, average daily gain, dry matter intake, or feed efficiency. Neither on ingestive behavior activities and plasma concentrations of urea, creatine, aspartate aminotransferase, gamma-glutamyl transferase, and creatine kinase no effects were detected between diets. The inclusion of plants in nature in steer’s diet did not negatively impact performance and health. However, further field studies with beef cattle are needed for greater clarification of its effects and dosages.

Nephro-protective activity of wheatgrass juice against alcohol-induced oxidative damage in rats

The present study is an attempt to check the protective effect of fresh wheatgrass juice (WJ) as a potential therapeutic agent against alcohol-induced oxidative/nitrosative stress leading to nephrotoxicity in rats. Administration of 20% ethanol (5 g/kg b.wt/day) for 60 days resulted in a significant rise in the plasma concentrations of urea and creatinine with decreased levels of uric acid. Besides, a significant decrease in plasma electrolyte/mineral levels along with decreased activity of Na+/K+-ATPase activity was recorded in alcohol administered rats. In alcohol administered rats augmented lipid peroxidation (thio-barbituric acid reactive substance – TBARS) and nitric oxide (NOx) reflects the increased oxidative stress and nitrosative stress, moreover, we noticed a concomitant decrease in the levels of reduced glutathione (GSH) with decreased activities of antioxidant enzyme machinery viz., superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione s-transferase (GST). Administration of WJ to the alcoholic rats significantly restored the plasma biochemical markers and the kidney antioxidant status near to control group animal levels. These findings were further confirmed by the kidney histopathological studies, wherein the protective effect of WJ treatment in retaining the morphological features of the renal tissue in spite of the alcohol administration was evident. The rich repertoire of phenolic compounds present in the WJ from the freshly sprouted seeds synergistically protected the kidney from alcohol-induced damage.

Sodium Oxalate-Induced Acute Kidney Injury Associated With Glomerular and Tubulointerstitial Damage in Rats.

Acute crystalline nephropathy is closely related to tubulointerstitial injury, but few studies have investigated glomerular changes in this condition. Thus, in the current study, we investigated the factors involved in glomerular and tubulointerstitial injury in an experimental model of crystalline-induced acute kidney injury (AKI). We treated male Wistar rats with a single injection of sodium oxalate (NaOx, 7 mg⋅100 g–1⋅day–1, resuspended in 0.9% NaCl solution, i.p.) or vehicle (control). After 24 h of treatment, food and water intake, urine output, body weight gain, and renal function were evaluated. Renal tissue was used for the morphological studies, quantitative PCR and protein expression studies. Our results revealed that NaOx treatment did not change metabolic or electrolyte and water intake parameters or urine output. However, the treated group exhibited tubular calcium oxalate (CaOx) crystals excretion, followed by a decline in kidney function demonstrated along with glomerular injury, which was confirmed by increased plasma creatinine and urea concentrations, increased glomerular desmin immunostaining, nephrin mRNA expression and decreased WT1 immunofluorescence. Furthermore, NaOx treatment resulted in tubulointerstitial injury, which was confirmed by tubular dilation, albuminuria, increased Kim-1 and Ki67 mRNA expression, decreased megalin and Tamm–Horsfall protein (THP) expression. Finally, the treatment induced increases in CD68 protein staining, MCP-1, IL-1β, NFkappaB, and α-SMA mRNA expression, which are consistent with proinflammatory and profibrotic signaling, respectively. In conclusion, our findings provide relevant information regarding crystalline-induced AKI, showing strong tubulointerstitial and glomerular injury with a possible loss of podocyte viability.

Grass clover intake and effects of reduced dietary protein for organic sows during summer

Energy spent on thermoregulation and locomotive activity may increase the energy requirements of outdoor relative to indoor housed sows, whilst their protein requirement most likely is comparable on a daily basis but lower per kg of feed. The purpose of this study was to quantify the energy and protein intake from compound feed and grazing and the energy and protein needed for maintenance, maternal retention, milk production, thermoregulation and locomotive activity in organic sows during summer, to understand how nutrition of organic sows could be improved. A total of 41 2nd parity sows (Landrace x Yorkshire; 239 kg at insemination) were reared outdoor under organic conditions for six months. Sows were fed one of two iso-energetic diets, either commercial available gestation and lactation diets (control strategy), or a 12% lower protein supply obtained by diluting the control diets with a low protein supplement. Sows had ad libitum access to a plentiful grass clover sward and were supplied similar amounts of metabolizable energy (ME) from compound feed equivalent to 10% above the energy recommended for indoor sows. Collections of plasma and urine were performed on d 60 and d 100 of gestation and plasma, urine and milk was collected on d 5, 20 and 40 of lactation. On all sample collection days, sows (and piglets; n=671) were weighed individually, sows were back fat scanned and heart rate and locomotive activity was registered with a global positioning system (GPS) tracker. Sow body composition was estimated using a deuterium dilution technique, which allowed retention or mobilisation of protein and fat to be calculated. Grass intake was estimated via plasma pipecolic acid. Daily grass clover intake was on average 420 g DM/d during gestation, 574 g DM/d at peak lactation and 472 g DM/d on d 40 of lactation, corresponding to 2.4, 3.2 and 2.6 kg of fresh grass. There was an increased grass clover intake in the low protein group, as they consumed 14% more grass (37 g DM/d extra) than the sows fed the normal protein compound feed (P=0.007). Estimated milk yield peaked at 16.3 kg/d on d20. This experiment showed no effects of dietary protein level on urinary pH, urea or creatinine and no effects on plasma glucose, urea, lactate, triglycerides, creatinine or NEFA concentrations. It was possible to reduce the protein content of organic compound feed in the summer time as grazing pregnant sows obtained 16-17% of their daily SID lysine requirement from the sward in mid and late gestation. In conclusion, the daily protein- and amino acid requirements were met by feed and grass consumption during pregnancy but not in early and at peak lactation due to insufficient feed intake. The total energy requirement of high yielding second parity outdoor sows during a normal Danish summer was found to be around 32 MJ ME/d during gestation and approximately 130 MJ ME/d at peak lactation.

Niche partitioning between river shark species is driven by seasonal fluctuations in environmental salinity

Abstract Tropical rivers and estuaries are highly dynamic environments, where environmental conditions change dramatically over spatial and temporal scales. This creates both physiological and ecological challenges for euryhaline elasmobranchs, where fluctuations in salinity can impact not only osmoregulatory function but also the ability to find and acquire prey. We investigated how spatial and temporal variation in environmental salinity influences physiological homoeostasis, habitat utilization and migration timing in two euryhaline carcharhinid sharks within a tropical river in northern Australia. Neonate and juvenile bull sharks Carcharhinus leucas and speartooth sharks Glyphis glyphis were tracked over a 4‐year period using implanted acoustic tags and an array of hydrophone receivers. Tissue samples were also collected from captured sharks and analysed for interspecific differences in plasma osmolarity, urea and electrolyte (Na+ and K+) concentrations and the stable isotopes δ13C and δ15N. We discovered that immature C. leucas and G. glyphis segregate spatially along a salinity gradient between September and December, where the mean volume of intersection between species dropped as low as 0.01. While G. glyphis used higher salinity environments (mean salinity = 19.22) located between 30 and 70 km from the mouth of the estuary, C. leucas occupied freshwater reaches (mean salinity = 1.98) between 60 and 110 km upstream. Plasma osmolarities of both species were always hyperosmotic to the environment, with electrolyte concentrations maintained within a narrow range independent of environmental osmolarities. At the onset of the wet season, both C. leucas and G. glyphis undertook a coordinated downstream migration towards the lower estuary before returning upstream. Carcharhinus leucas blood tissues were more enriched in δ15N and δ13C than samples collected from similar size G. glyphis, suggesting that these species not only spatially segregate within low salinity habitats but also prey on different dietary resources. Furthermore, a loss of enriched isotopic values in fin tissue with increasing body length provides further support for marine use by adult sharks in conjunction with dependence on rivers as important nursery habitat. Our results illustrate the importance of long‐term integrative studies into resource competition and the significance of discrete brackish habitats for threatened euryhaline elasmobranchs. A free Plain Language Summary can be found within the Supporting Information of this article.

Time-Dependent miRNA Profile during Septic Acute Kidney Injury in Mice.

(1) Background: Lipopolysaccharide (LPS)-induced systemic inflammation is associated with septic acute kidney injury (AKI). We investigated the time-dependent miRNA expression changes in the kidney caused by LPS. (2) Methods: Male outbred NMRI mice were injected with LPS and sacrificed at 1.5 and 6 h (40 mg/kg i.p., early phase, EP) or at 24 and 48 h (10 mg/kg i.p., late phase, LP). The miRNA profile was established using miRCURY LNA™ microarray and confirmed with qPCR. Total renal proteome was analyzed by LC-MS/MS (ProteomeXchange: PXD014664). (3) Results: Septic AKI was confirmed by increases in plasma urea concentration and in renal TNF-α and IL-6 mRNA expression. Most miRNAs were altered at 6 and 24 h and declined by 48 h. In EP miR-762 was newly identified and validated and was the most elevated miRNA. The predicted target of miR-762, Ras related GTPase 1B (Sar1b) was downregulated. In LP miR-21a-5p was the most influenced miRNA followed by miR-451a, miR-144-3p, and miR-146a-5p. Among the potential protein targets of the most influenced miRNAs, only aquaporin-1, a target of miR-144-3p was downregulated at 24 h. (4) Conclusion: Besides already known miRNAs, septic AKI upregulated miR-762, which may regulate GTP signaling, and miR-144-3p and downregulated its target, aquaporin-1.