Plasma Lactate Concentrations Research Articles

Intraoperative increased plasma lactate concentration as a prognostic factor for liver transplant recipients: a retrospective cohort study

Intraoperative increased plasma lactate concentration as a prognostic factor for liver transplant recipients: a retrospective cohort study

Automated Partial Versus Complete Resuscitative Endovascular Balloon Occlusion of the Aorta for the Management of Hemorrhagic Shock in a Pig Model of Polytrauma: a Randomized Controlled Pilot Study.

Endovascular variable aortic control (EVAC) is an automated partial resuscitative endovascular balloon occlusion of the aorta (REBOA) platform designed to mitigate the deleterious effects of complete REBOA. Long-term experiments are needed to assess potential benefits. The feasibility of a 24-hour experiment in a complex large animal trauma model remains unknown. Anesthetized swine were subjected to controlled hemorrhage, blunt thoracic trauma, and tibial fractures. Animals were then randomized (N=3/group) to control (No balloon support), 90minutes of complete supraceliac REBOA, or 10minutes of supraceliac REBOA followed by 80minutes of EVAC. One hundred ten minutes after injury, animals were resuscitated with shed blood, the REBOA catheter was removed. Automated critical care under general anesthesia was maintained for 24hours. Animals in the control and EVAC groups survived to the end of the experiment. Animals in the REBOA group survived for 120, 130, and 660minutes, respectively. Animals in the EVAC group displayed similar mean arterial pressure and plasma lactate concentration as the control group by the end of the experiment. Histologic analysis suggested myocardial injury in the REBOA group when compared with controls. This study demonstrates the feasibility of intermediate-term experiments in a complex swine model of polytrauma with 90minutes of REBOA. EVAC may be associated with improved survival at 24hours when compared with complete REBOA. EVAC resulted in normalized physiology after 24hours, suggesting that prolonged partial occlusion is possible. Longer studies evaluating partial REBOA strategies are needed.

Alternative Cerebral Fuels in the First Five Days in Healthy Term Infants: The Glucose in Well Babies (GLOW) Study

To determine plasma lactate and beta-hydroxybutyrate (BHB) concentrations of healthy infants in the first 5days and their relationships with glucose concentrations. Prospective masked observational study in Hamilton, New Zealand. Term, appropriately grown singletons had heel-prick blood samples, 4 in the first 24hours then twice daily. In 67 infants, plasma lactate concentrations were higher in the first 12hours (median, 20; range, 10-55 mg/dL [median, 2.2mmol/L; range, 1.1-6.2mmol/L]), decreasing to 12mg/dL (range, 7-29mg/dL [median, 1.4mmol/L; range, 0.8-3.3mmol/L]) after 48hours. Plasma BHB concentrations were low in the first 12hours (median,0.9mg/dL; range, 0.5-5.2mg/dL [median, 0.1mmol/L; range, 0.05-0.5mmol/L]), peaked at 48-72hours (median, 7.3mg/dL; range, 1.0-25.0mg/dL [median, 0.7mmol/L; range, 0.05-2.4mmol/L]), and decreased by 96hours (median, 0.9mg/dL; range, 0.5-16.7mg/dL [median, 0.1mmol/L; range, 0.05-1.6mmol/L]). Compared with infants with plasma glucose concentrations above the median (median, 67mg/dL [median, 3.7mmol/L]), those with lower glucose had lower lactate concentrations in the first 12hours and higher BHB concentrations between 24 and 96hours. Lower interstitial glucose concentrations were also associated with higher plasma BHB concentrations, but only if the lower glucose lasted greater than 12hours. Glucose contributed 72%-84% of the estimated potential adenosine triphosphate throughout the 5days, with lactate contributing 25% on day 1 and BHB 7% on days 2-3. Lactate on day 1 and BHB on days 2-4 may contribute to cerebral fuels in healthy infants, but are unlikely to provide neuroprotection during early or acute hypoglycemia. The Australian and New Zealand Clinical Trials Registry: ACTRN12615000986572.

Intramuscular cobinamide as an antidote to methyl mercaptan poisoning

Background Methyl mercaptan occurs naturally in the environment and is found in a variety of occupational settings, including the oil, paper, plastics, and pesticides industries. It is a toxic gas and deaths from methyl mercaptan exposure have occurred. The Department of Homeland Security considers it a high threat chemical agent that could be used by terrorists. Unfortunately, no specific treatment exists for methyl mercaptan poisoning. Methods We conducted a randomized trial in 12 swine comparing no treatment to intramuscular injection of the vitamin B12 analog cobinamide (2.0 mL, 12.5 mg/kg) following acute inhalation of methyl mercaptan gas. Physiological and laboratory parameters were similar in the control and cobinamide-treated groups at baseline and at the time of treatment. Results All six cobinamide-treated animals survived, whereas only one of six control animals lived (17% survival) (p = 0.0043). The cobinamide-treated animals returned to a normal breathing pattern by 3.8 ± 1.1 min after treatment (mean ± SD), while all but one animal in the control group had intermittent gasping, never regaining a normal breathing pattern. Blood pressure and arterial oxygen saturation returned to baseline values within 15 minutes of cobinamide-treatment. Plasma lactate concentration increased progressively until death (10.93 ± 6.02 mmol [mean ± SD]) in control animals, and decreased toward baseline (3.79 ± 2.93 mmol [mean ± SD]) by the end of the experiment in cobinamide-treated animals. Conclusion We conclude that intramuscular administration of cobinamide improves survival and clinical outcomes in a large animal model of acute, high dose methyl mercaptan poisoning.

Plasma BCAA concentrations during exercise of varied intensities in young healthy men-the impact of endurance training.

BackgroundBranched-chain amino acids (BCAA) i.e., leucine (Leu), isoleucine (Ile) and valine (Val) are important amino acids, which metabolism play a role in maintaining system energy homeostasis at rest and during exercise. As recently shown lowering of circulating BCAA level improves insulin sensitivity and cardiac metabolic health. However, little is known concerning the impact of a single bout of incremental exercise and physical training on the changes in blood BCAA. The present study aimed to determine the impact of a gradually increasing exercise intensity—up to maximal oxygen uptake (VO2max) on the changes of the plasma BCAA [∑BCAA]pl, before and after 5-weeks of moderate-intensity endurance training (ET).MethodsTen healthy young, untrained men performed an incremental cycling exercise test up to exhaustion to reach VO2max, before and after ET.ResultsWe have found that exercise of low-to-moderate intensity (up to ∼50% of VO2max lasting about 12 min) had no significant effect on the [∑BCAA]pl, however the exercise of higher intensity (above 70% of VO2max lasting about 10 min) resulted in a pronounced decrease (p < 0.05) in [∑BCAA]pl. The lowering of plasma BCAA when performing exercise of higher intensity was preceded by a significant increase in plasma lactate concentration, showing that a significant attenuation of BCAA during incremental exercise coincides with exercise-induced acceleration of glycogen utilization. In addition, endurance training, which significantly increased power generating capabilities at VO2max (p = 0.004) had no significant impact on the changes of [∑BCAA]pl during this incremental exercise.ConclusionWe have concluded that an exercise of moderate intensity of relatively short duration generally has no effect on the [∑BCAA]pl in young, healthy men, whereas significant decrease in [∑BCAA]pl occurs when performing exercise in heavy-intensity domain. The impact of exercise intensity on the plasma BCAA concentration seems to be especially important for patients with cardiometabolic risk undertaken cardiac rehabilitation or recreational activity.

Physiological and biochemical responses and hydration status in equines after two barrel racing courses

ABSTRACT: Studies on biochemical constituents and hydration of horses in training or competitions are essential for the knowledge of their adaptive physiological and metabolic responses to the type of exercise inherent to the sport. The present research evaluated the effects of exercise on hydric status and physiologic and biochemical profiles in Quarter Horses during a barrel race training session. The design consisted of three evaluation times (T): at rest, before the start of physical activity (T0); immediately after a 10-minute warm-up trot and then running the barrel race courses twice with a 10-minute interval (T1); and after one hour’s rest after the second course (T2). The parameters analyzed were: heart rate (HR), respiratory rate (RR), body temperature (BT) and mucose color; the capillary refill time (CRT), packed cell volume (PCV), total plasma proteins (TPP), serum creatinine (CRE) and blood urea nitrogen (BUN) were evaluated and used to infer water status; plasma osmolarity (Osm) was measured; the electrolytes sodium (Na), potassium (K), chloride (Cl), total calcium (tCa), total magnesium (tMg) and phosphorus (P), plasma glucose (Glu) and lactate (Lac) and the muscle enzymes creattine kinase (CK) and aspartate aminotransferase (AST) completed the evaluated parameters. The data for the variables studied were submitted to ANOVA and the Tukey test at 5% probability. After exercise (in T1), HR, RR, BT, PCV, TPP, Glu, Lac, Cre increased (P&lt;0.05), there was also increase in phosphorus and decrease in K (P&lt;0.05), but there was no hypophosphatemia and hipokalemia, respectively. After rest (in T2), only glucose returned to baseline levels (T0) and, with lower mean values, HR, RR, BT, PCV, K and Lac did not return to baseline levels (T0), while P decreased (P&lt;0.05). Osm, BUN, Na, Cl, tCa, tMg, CK and AST did not change between times (P&gt;0.05). It was concluded that the maximum intensity exercise performed on two barrel race courses caused mild hemoconcentration, did not changed plasma osmolality or concentrations of important electrolytes and muscle enzymes of horses, but caused hyperlactatemia without the plasma lactate concentrations being fully recomposed after resting.

Effect of Acute Sprint Exercise on Myokines and Food Intake Hormones in Young Healthy Men.

Physical exercise is known to influence hormonal mediators of appetite, but the effect of short-term maximal intensity exercise on plasma levels of appetite hormones and cytokines has been little studied. We investigated the effect of a 30 s Wingate Test, followed by a postprandial period, on appetite sensations, food intake, and appetite hormones. Twenty-six physically active young males rated their subjective feelings of hunger, prospective food consumption, and fatigue on visual analogue scales at baseline, after exercise was completed, and during the postprandial period. Blood samples were obtained for the measurement of nesfatin-1, ghrelin, leptin, insulin, pancreatic polypeptide (PP), human growth factor (hGH) and cytokine interleukin-6 (IL-6), irisin and plasma lactate concentrations, at 30 min before exercise, immediately (210 s) after exercise, and 30 min following a meal and at corresponding times in control sedentary males without ad libitum meal intake, respectively. Appetite perceptions and food intake were decreased in response to exercise. Plasma levels of irisin, IL-6, lactate, nesfatin-1 and ghrelin was increased after exercise and then it was returned to postprandial/control period in both groups. A significant rise in plasma insulin, hGH and PP levels after exercise was observed while meal intake potentiated this response. In conclusion, an acute short-term fatiguing exercise can transiently suppress hunger sensations and food intake in humans. We postulate that this physiological response involves exercise-induced alterations in plasma hormones and the release of myokines such as irisin and IL-6, and supports the notion of existence of the skeletal muscle–brain–gut axis. Nevertheless, the detailed relationship between acute exercise releasing myokines, appetite sensations and impairment of this axis leading to several diseases should be further examined.

The Effects of Exogenous Lactate Administration on the IGF1/Akt/mTOR Pathway in Rat Skeletal Muscle.

We investigated the effects of oral lactate administration on protein synthesis and degradation factors in rats over 2 h after intake. Seven-week-old male Sprague–Dawley rats were randomly divided into four groups (n = 8/group); their blood plasma levels of lactate, glucose, insulin, and insulin-like growth factor 1 (IGF1) were examined following sacrifice at 0, 30, 60, or 120 min after sodium lactate (2 g/kg) administration. We measured the mRNA expression levels of protein synthesis-related genes (IGF receptor, protein kinase B (Akt), mammalian target of rapamycin (mTOR)) or degradation-related genes (muscle RING-finger protein-1 (MuRF1), atrogin-1) and analyzed the protein expression and phosphorylation (activation) of Akt and mTOR. Post-administration, the plasma lactate concentration increased to 3.2 mmol/L after 60 min. Plasma glucose remained unchanged throughout, while insulin and IGF1 levels decreased after 30 min. The mRNA levels of IGF receptor and mTOR peaked after 60 min, and Akt expression was significantly upregulated from 30 to 120 min. However, MuRF1 and atrogin-1 expression levels were unaffected. Akt protein phosphorylation did not change significantly, whereas mTOR phosphorylation significantly increased after 30 min. Thus, lactate administration increased the mRNA and protein expression of protein-synthesis factors, suggesting that it can potentially promote skeletal muscle synthesis.

Betaine and Isoquinoline Alkaloids Protect against Heat Stress and Colonic Permeability in Growing Pigs.

Heat stress (HS) compromises productivity of pork production, in part as a result of increased oxidative stress and inflammatory responses, particularly within the gastrointestinal tract. This study aimed to investigate whether plant-derived betaine and isoquinoline alkaloids could ameliorate HS in pigs. Fifty female Large White × Landrace grower pigs, which were acclimated to control (CON), control plus betaine (BET), or control plus isoquinoline alkaloids (IQA) diets for 14 days were then exposed to heat stress or thermoneutral condition. Both BET and IQA partially ameliorated increases in respiration rate (p = 0.013) and rectal temperature (p = 0.001) associated with HS conditions. Heat stress increased salivary cortisol concentrations and reduced plasma creatinine, lactate, and thyroid hormone concentrations. Heat stress increased colon FD4 permeability, which was reduced by IQA (p = 0.030). Heat stress increased inflammation in the jejunum and ileum, as indicated by elevated interleukin-1β (p = 0.022) in the jejunum and interleukin-1β (p = 0.004) and interleukin-8 (p = 0.001) in the ileum. No differences in plasma total antioxidant capacity (TAC) were observed with HS, but betaine increased plasma TAC compared to IQA. Dietary BET increased betaine concentrations in the jejunum, ileum (p < 0.001 for both), plasma, liver, kidney (p < 0.010 for all), urine (p = 0.002) and tended to be higher in muscle (p = 0.084). Betaine concentration was not influenced by HS, but it tended to be higher in plasma and accumulated in the liver. These data suggest that betaine and isoquinoline alkaloids supplementation ameliorated consequences of heat stress in grower pigs and protected against HS induced increases in colonic permeability.

Effects of Lactanase on the plasma lactate response to intense exercise in horses

A commonly held belief is that lactate production during exercise limits performance via fatigue. The current study aimed to assess the effects of a supplement marketed as performance enhancing (Lactanase®) on equine exercise performance and plasma lactate concentrations. Lactanase was expected to alter exercise performance and plasma lactate. Eight healthy, unfit Standardbred horses (four geldings and four mares, 9±3 years, 489±33 kg, mean ± standard error) were administered Lactanase (5 doses of 25 g) top-dressed on a commercial pelleted ration or unsupplemented pellets (Control) in a cross-over design experiment. Doses were administered over a four-day period and horses performed a graded exercise test on the fourth day following the final dose of either Lactanase or control. Blood samples (20 ml) were obtained via jugular catheter 30 min prior to exercise, immediately prior to exercise, in the last 10 s of each incremental exercise step, and 5 and 60 min post-exercise. Samples were frozen at -80 °C until further analysis. Data were analysed using a two-way repeated measures ANOVA. Statistically different means were separated using Student-Newman-Keuls and Dunnetts. No differences (P&gt;0.05) in total run time were observed following Lactanase administration. Plasma lactate increased (P&lt;0.05) when horses reached a speed of 7 m/s and remained elevated through 60 min post-exercise. There was no effect (P&gt;0.05) of Lactanase on the plasma lactate response during exercise. Similarly, supplementation did not affect (P&gt;0.05) plasma glucose or total protein at any time point. Exercise did increase plasma total protein (P&lt;0.05), but it returned to baseline levels by 60 min post-exercise. Plasma glucose was elevated (P&lt;0.05) post-exercise. These results indicate Lactanase administration does not alter the lactate response or the total run time to fatigue during intense incremental exercise in horses.

Abundance of the skeletal muscle Glut-4 glucose transport protein in Standardbred foals during development and exercise

The objective of this study was to investigate the changes in Glut-4 expression in gluteus muscle, and in the plasma concentrations of hormones and metabolites during the suckling period, after weaning, and after exercise training in foals. Our hypotheses were Glut-4 abundance will decrease following metabolite and hormonal concentration between neonatal period and late development but will increase with exercise training. Eight clinically normal Standardbred foals were used in this study, and they stayed with their mothers from birth until weaning at 6 months. After weaning, the foals were randomly divided in two groups: an exercise group (EX) (n=4; ~282 kg) which trained 3 d/wk for 12 wks and a control group (n=4; ~271 kg) without structured exercise. Venous blood samples were obtained immediately after birth (&lt;30 min), at 24 h, at day 7 and day 14, and at 1, 3, 6, 9 and 12 months after parturition. Results were analysed using one-way ANOVA for repeated measures. Post-hoc differences were identified using the Tukey test and correlations were obtained using Pearson product moment analysis. The abundance of Glut-4 in skeletal muscle was highest immediately after birth and with growth and development (P&lt;0.05). Exercise training did not change Glut-4 abundance (P&gt;0.05). Plasma lactate, insulin and cortisol concentrations decreased during the first three months of lactation while glucose and leptin concentrations increased (P&lt;0.05). There were no effects of exercise training on any of the above plasma parameters (P&gt;0.05). In conclusion, Glut-4 abundance in gluteus muscle was highest at the birth and decreased during development and exercise training for 12 weeks did not change its’ abundance.

Evaluation of the rectal-interdigital temperature gradient as a diagnostic marker of shock in dogs.

To evaluate the difference in the rectal-interdigital temperature gradient (RITG) between dogs that were presented to an emergency room with clinical signs of shock compared to those without signs of shock, and if this gradient can be used as a diagnostic marker for shock. Prospective, single center, observational study conducted from 2014 to 2015. University veterinary teaching hospital. Twenty dogs with a clinical diagnosis of shock and 60 dogs without a clinical diagnosis of shock (controls). Upon presentation to the emergency room and prior to intervention, measurements of rectal temperature, interdigital temperature, ambient temperature, systemic markers of perfusion (capillary refill time [CRT], heart rate [HR], respiratory rate [RR], Doppler blood pressure [DBP], and venous plasma lactate concentration), and venous blood gas analytes were recorded. Dogs were initially determined to be in shock by the attending clinician, and post hoc inclusion criteria were applied. Shock was defined as abnormalities in ≥3 of the 6 following criteria: HR>120/min, RR>40/min, CRT>2seconds, rectal temperature<37.8°C (100.0°F), venous plasma lactate concentration>2.5mmol/L, or DBP<90mm Hg. Animals with circulatory shock had a significantly increased RITG. An increased RITG was also correlated with individual perfusion parameters including prolonged CRT (ρ =.353, P= 0.0013), tachycardia (ρ =.3485, P= 0.0015), decreased DBP (ρ =-0.6162, P= 0.0003), and shock index (ρ = 0.6168, P= 0.0003). Receiver operator curve analysis indicated a RITG cutoff point of 11.6°F had 90% specificity for the diagnosis of shock (area under the curve= 0.7604). The RITG in this study was associated with a diagnosis of shock and therefore may serve as a diagnostic marker of circulatory shock. Future studies with larger sample sizes to validate the use of temperature gradients and other peripheral perfusion abnormalities as diagnostic and monitoring tools are warranted.

Effects of Pre-Cooling on Thermophysiological Responses in Elite Eventing Horses.

Simple SummaryHorses have a high metabolic capacity for exercise, producing a great deal of heat, and have a small surface area for heat loss. Under limited circumstances, the regulation of heat loss (i.e., across the respiratory tract and by the evaporation of sweat) means heat build-up in the body is reduced. Thermoregulation can be assisted by cooling the horses down to safely perform exercise in thermally challenging environments. The present study showed that pre-cooling (i.e., cooling between the warm-up and exercise performance) slightly reduced the rise in rectal, shoulder and rump skin temperatures of ten international eventing horses during moderately intense canter training in moderate environmental conditions. During the canter training, heart rate, sweat rate and sweat composition were unaffected by pre-cooling. The pre-cooling strategy chosen here was cold-water rinsing for a short period of time (~8 min). Considering the limited time and space at equestrian events, such a pre-cooling strategy could easily be implemented. Reducing heat strain by pre-cooling may potentially improve equine welfare during events.In this study, we examined the effects of pre-cooling on thermophysiological responses in horses exercising in moderate environmental conditions (average wet bulb globe temperature: 18.5 ± 3.8 °C). Ten international eventing horses performed moderate intensity canter training on two separate days, and were either pre-cooled with cold-water rinsing (5–9 °C for 8 ± 3 min; cooling) or were not pre-cooled (control). We determined velocity (V), heart rate (HR), rectal temperature (Tre,), shoulder and rump skin temperature (Tshoulder and Trump), plasma lactate concentration (LA), gross sweat loss (GSL), and local sweat rate (LSR), as well as sweat sodium, chloride and potassium concentrations. The effect of pre-cooling on Tre was dependent on time; after 20 min of exercise the effect was the largest (estimate: 0.990, 95% likelihood confidence intervals (95% CI): 0.987, 0.993) compared to the control condition, resulting in a lower median Tre of 0.3 °C. Skin temperature was also affected by pre-cooling compared to the control condition (Tshoulder: −3.30 °C, 95% CI: −3.739, −2.867; Trump: −2.31 °C, 95% CI: −2.661, −1.967). V, HR, LA, GSL, LSR and sweat composition were not affected by pre-cooling. In conclusion, pre-cooling by cold-water rinsing could increase the margin for heat storage, allowing a longer exercise time before a critical Tre is reached and, therefore, could potentially improve equine welfare during competition.

Clinicopathological abnormalities associated with increased animal triage trauma score in cats presenting for vehicular trauma: 75 cases (1998-2009).

To document the clinical and clinicopathological changes in cats presenting with vehicular trauma (VT) and to determine whether the calculated animal trauma triage (ATT) score was associated with any clinicopathological abnormalities. Retrospective descriptive study conducted between 1998 and 2009. University veterinary teaching hospital. Seventy-five client-owned cats that presented for VT to an urban veterinary hospital. None. Pertinent history, physical examination findings, results of biochemical testing, and outcome were extracted from medical records. ATT score was calculated based on physical examination. Patients were classified as having either a low (<5) ATT (n=30) or a high (≥5) ATT (n=45) score. Male cats were overrepresented (60.0%), and a majority of cats had outdoor access (65.3%). Low PCV (P= 0.024), low total plasma protein concentration (P= 0.032), low venous blood pH (P= 0.047), high plasma lactate concentration (P= 0.047), low plasma bicarbonate concentration (P= 0.047), low base excess (P= 0.047), and high plasma glucose concentration (P= 0.047) were associated with higher ATT scores. In addition, low noninvasive blood pressure measurements (P= 0.008) were associated with higher ATT scores. There was a significant association between lower PCV, lower total plasma protein concentration, lower venous blood pH, higher plasma lactate concentration, lower plasma bicarbonate concentration, lower base excess, higher whole blood glucose concentration, and lower noninvasive blood pressure and higher ATT scores at presentation in feline patients suffering from VT. Prospective evaluation of these values may prove useful in furthering understanding of the pathophysiology of trauma in cats.

The distinctive short-term response of late-pregnant prolific ewes to propylene glycol or glycerol drenching

Pregnancy toxemia is the most frequent metabolic disorder of ewes in late pregnancy. Although propylene glycol (PG) and glycerol (GLY) are common glucogenic supplements for treating pregnancy toxemia in ewes, the relative benefit of these 2 supplements is not entirely clear. Therefore, the objectives of the present study were to determine the changes during 24 h in key blood metabolites and insulin in response to PG or GLY drenching in prolific ewes. To this end, 36 multiparous late-pregnant Afec-Assaf ewes (∼132.4 d pregnant) bearing 2 to 4 fetuses, divided into 2 blocks (18 ewes in each block), with a blood β-hydroxybutyrate (BHB) concentration of 0.5 to 1.6 mmol/L were included. Ewes were divided into 3 groups (12 ewes each; 6 ewes in each experimental day), according to their BHB levels, expected litter size, body weight, and body condition score, and were drenched with the following: (1) control group (CTL), 55 mL of water; (2) PG, 106 mL of PG (100% PG, 448 calories); or (3) GLY, 108 mL of Koforin 80 (80% GL; 448 calories). Blood samples were taken before drenching and every hour after drenching for 24 h. Plasma concentration of glucose, BHB, nonesterified fatty acids, lactate, glycerol, and insulin were determined. Because there were no effects of treatments after 12 h in the first block, the data were analyzed for 12 h after drenching rather than 24 h. The plasma glucose concentration during the first 5 h after drenching was the highest in the GLY, BHB concentration was the lowest in the PG, and the nonesterified fatty acid levels were lower in the PG compared with the CTL ewes during the first 5 h after drenching. However, glucose concentration was higher in the PG ewes at 9, 11, and 12 h after drenching than in CTL or GLY ewes. The mean lactate concentration in plasma for 12 h was 2.5- and 1.9-fold higher in the PG compared with the CTL and GLY ewes, respectively, and except at 11 h after drenching, it was significantly higher at each time point. The insulin concentration was higher in the GLY than in both other groups at 2 to 5 h after drenching. These results suggest that during the first few hours after drenching the effect of PG was more effective in reducing the BHB concentration, whereas the GLY effect was more effective in enhancing glucose concentration. The increased concentration in lactate following PG treatment suggests that the PG contribution to gluconeogenesis is mediated through its metabolism to lactate. In contrast, the lack of an effect on lactate, and the faster increase in blood glucose in response to GLY suggest that GLY has a more advanced entry point to gluconeogenesis, which influences the immediate response in enhancing the glucose blood concentration.

Etiology and prognosis for dogs with abnormal blood glucose concentrations evaluated in an emergency room.

To determine the prevalence of glucose abnormalities in nondiabetic dogs presenting to a veterinary emergency room (ER) and their association with underlying disease processes, previous glucocorticoid administration, and overall mortality. Single-center, retrospective study from January 2013 to December 2014. University Teaching Hospital. A total of 660 dogs presenting to an ER with a blood glucose concentration measured within 6 hours of presentation. None. Medical records from dogs with a blood glucose concentration measured within 6 hours of hospital admission were reviewed. Medications administered prior to blood sampling, the presence of shock, final clinical diagnosis, and survival were recorded. Hypoglycemia and hyperglycemia were defined as a blood glucose<4.4mmol/L (80mg/dL) and>6.7mmol/L (120mg/dL), respectively. Diabetic patients were removed from analysis. Hyperglycemia was found in 40.1% of dogs, whereas hypoglycemia was present in 9.0%. Hyperglycemia was most often associated with gastrointestinal disease, trauma, neoplasia, and respiratory disease. The most common diseases associated with hypoglycemia were sepsis, gastrointestinal disease, and neoplasia. Dogs in shock or with hyperlactatemia had higher blood glucose values than dogs with normal perfusion and plasma lactate concentrations (P= 0.016 and P< 0.0001, respectively). Mortality was higher in dogs with hyperglycemia (33.2%, P= 0.03) or hypoglycemia (44.6%, P= 0.0024) compared to those with normoglycemia (24.9%). Dysglycemia in nondiabetic dogs evaluated in an ER was associated with a higher mortality rate than dogs in the same population with normoglycemia. Hyperglycemia in this population was common and may represent a stress response.

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.

Efficacy of Glyceryl trinitrate (GTN) to facilitate the rewarming process during cardiopulmonary bypass

BackgroundDoes Glyceryl trinitrate (GTN) administered during rewarming on cardiopulmonary bypass (CPB) impact: time to completion of rewarming prior to separation from CPB circuit, early post-op patient peripheral – core temperature gradient, time to maintenance of normothermia (core temperature > 36.5 °C) for minimum of 2 h in the initial post-op period, and plasma lactate concentrations initially post-CPB.MethodsSingle centre prospective randomized trial conducted in the Mater Misericordiae University teaching hospital in Dublin Ireland. Trial registration: ISRCTN registry, ISRCTN10480871, registered 16th of August 2017. 82 patients enrolled. Patients randomised to low dose GTN infusion (0.01 mcg/kg/min) or higher dose GTN infusion (0.5 mcg/kg/min) during rewarming on CPB.Measurements and Main resultsThere was no significant difference between the treatment arms for the total time to being rewarmed, U = 759.0, p = 0.84. There were also no differences between the treatment arms for the time to achieve core temperature greater than 36.5 after two hours, U = 714.0, p = 0.52, the time to achieve plateau core skin temperature, U = 688.0, p = 0.37, and the post-intervention protamine lactate, U = 721.0, p = 0.56.ConclusionsHigher dose GTN infusion during rewarming on CPB does not improve peripheral-core temperature gradient post operatively and has no effect on post-operative lactate concentrations.

Clinical evaluation of hyperimmune plasma for treatment of dogs with naturally occurring parvoviral enteritis.

To evaluate the clinical efficacy of a single infusion of hyperimmune plasma (HIP) in dogs with canine parvovirus (CPV). Prospective, randomized, placebo-controlled clinical trial. University teaching hospital. Client-owned dogs with naturally occurring CPV. Dogs presenting for CPV treatment (n=31) underwent cardiovascular resuscitation and were randomized to receive a single dose of either HIP (10mL/kg IV) or placebo (0.9% sodium chloride [10mL/kg IV]) during the first 6hours of hospitalization. All dogs were treated with a standardized treatment protocol (IV fluid therapy [120mL/kg/d isotonic crystalloids], cefoxitin [30mg/kg IV q 8 h], maropitant [1mg/kg IV q 24 h], and buprenorphine [0.01-0.02mg/kg IV q 8 h]) until hospital discharge. Dogs treated with HIP (n=16) demonstrated a lower shock index at 24 hours (median = 0.77, range: 0.5-1.5) than those treated with placebo (n=15, median = 1.34, range: 0.5-1.7; P= 0.02). Plasma lactate concentration was lower at 24 hours in HIP-treated dogs (median = 1.3mmol/L, range: 0.9-3.4mmol/L) than in placebo-treated dogs (median = 2.1mmol/L, range: 1.1-3.4mmol/L; P= 0.01). There was no difference in duration of hospitalization when comparing HIP-treated dogs (median = 3.2 days, range: 0.83-10 days) to placebo-treated dogs (median = 2.83 days, range: 1-8.38 days; P= 0.35). Survival was 16 of 16 (100%) for the HIP group and 14 of 15 (93.3%) for the placebo group (P= 0.32). HIP at 10mL/kg IV administered to dogs with CPV within the first 6hours of hospitalization improves markers of shock during the initial 24hours of hospitalization. No effects were observed on duration of hospitalization or mortality; however, this study was underpowered to evaluate these effects. HIP was well tolerated in this population of critically ill dogs.

A Test of Tradeoffs between Performance and Immunity in Water Snakes (Nerodia clarkii X Nerodia fasciata)

All organisms are constrained by limited energy and thus must allocate resources in such a way to maximize fitness. Due to their importance to survival, immunity and performance are each often favored in selective environments and thus may be tradeoffs of each other. To test this tradeoff hypothesis, we compared performance to three constitutive measures of immunity in a wild hybrid population of water snakes (Nerodia clarkii X Nerodia fasciata): agglutination response to sheep red blood cells (SRBC), heterophil: lymphocyte ratio (HLR), and bactericidal ability (BA). Performance was quantified by exercising snakes up to the point of loss of righting response (LRR) and measuring plasma lactate concentration at this point of fatigue. Support for the tradeoff hypothesis was mixed among the immune assays. Bactericidal ability had a significant positive correlation with LRR (P = 0.003, R2 = 0.263); this was counter to our tradeoff hypothesis and suggests that individuals invest in both traits simultaneously. We failed to detect a significant relationship between SRBC and performance. A significant negative relationship was found between HLR and LRR (P = 0.005, R2 = 0.237). Heterophil: lymphocyte ratio is a balance between innate and acquired immunity that is also indicative of baseline stress. This result showed that snakes with higher HLR are constrained and perform poorly compared to snakes with lower HLR, thus indicating a potential role of stress in affecting performance. Alternatively, this result may denote that internal tradeoffs in the immune system between innate and acquired immunity drive tradeoffs between immunity and performance. Snout–vent length (SVL) was significantly positively correlated with our performance measure (P = 0.012, R2 = 0.192). This result may be explained by selection driving increases in performance and/or ontogenetic development of the locomotor apparatus. Similarly, SVL was an important driver of immunity in snakes. Together, these results clearly show an important link exists between multiple physiological traits that are each vital to survival.