Beta-hydroxybutyrate Concentrations Research Articles

Efeito do estresse térmico sobre o consumo, indicadores bioquímicos, produção e qualidade do leite de vacas Holandês e Jersey

ABSTRACT: This research compared dry matter intake, milk yield, milk composition, and physiological and biochemical parameters between holstein and jersey cows under heat stress. Holstein (n=8) and Jersey (n=8) cows were allocated into two treatment groups: VA, with cooling, and SVA, with no cooling. The experiment included 14 days of adaptation (all the cows were cooled) and 5 days of evaluation (only the VA cows were cooled). Dry matter intake and milk production were measured daily. On Day 0 of the adaptation period and on Days 1, 3 and 5 of the evaluation period, milk samples were collected for composition, physicochemical and somatic cell analysis; blood was collected for analysis of the contents of total proteins, albumin, urea, creatinine, glucose, and beta-hydroxybutyrate. The physiological parameters measured were respiratory rate, surface temperature, rectal temperature and ruminal movements. The experimental design was a 2 × 3 factorial, with two treatments and three days. The data were subjected to ANOVA and tested for normality of the residuals. For dry matter intake, there was a treatment*day interaction, and the milk yield and composition of the treatments were similar. Only the protein content was greater in the VA treatment group than in the SVA group. The milk from SVA cows had greater resistance to ethanol than that from VA cows. The freezing point was greater in the VA treatment group. The concentration of beta-hydroxybutyrate was greater in the VA treatment group. A short heat stress period did not immediately affect production, but it did affect the composition and physicochemical properties of milk. The active cooling of cows with ventilation and sprinkling influences the amount of heat produced and retained, impacting the physiological parameters, blood metabolites, composition, and physicochemical properties of milk.

Peripartum energy metabolism of prolific ewes and their progeny in response to prepartum feeding and litter size

In late gestation, the increased energy demand to support the rapid fetal growth can induce an acute negative energy balance associated with a high risk of pregnancy toxemia, especially for prolific ewes (carrying two or more foetuses). The current study was conducted to evaluate the effects of dietary energy during the last 6 weeks prepartum on the energy metabolism dynamic responses and the newborn lamb metabolic profile in prolific ewes. Forty-five crossbred (Dorset × Romanov) ewes were randomly assigned to 1 of 3 dietary energy densities: ECTRL: 8.36 MJ of metabolizable energy (ME)/kg DM for weeks -6 to -3 relative to lambing, followed by 10.01 MJ ME/kg DM for weeks -2 and -1; EINCR: weekly increments from 7.99 to 12.69 MJ ME/kg DM; and EHIGH: 10.87 MJ ME/kg DM for the last 6 weeks of gestation. Dry matter intake (DMI; daily) and energy intake (MEI; daily), blood concentrations of beta-hydroxybutyrate (BHB) and glucose (every other day), as well as plasma concentrations of non-esterified fatty acids (NEFA; weekly), BW and body condition score (BCS; twice weekly) were determined throughout the experimental period. The effect of time on DMI and MEI varied based on dietary energy densities and litter size. During the last week before lambing, DMI decreased for EHIGH and EINCR ewes, as well as for ewes carrying quadruplets. On average, during week -5 to week -2 of gestation, EHIGH promoted the highest DMI and MEI, resulting in an increase of 0.16 BCS-points between the pre-treatment week and week -1 prepartum. In contrast, during the same period, BCS of ECTRL and EINCR ewes decreased by 0.35 and 0.19 points, respectively, which was reflected by higher NEFA concentrations compared with EHIGH ewes. The greater litter size was also associated with decreased BCS. Compared with twin-bearing ewes, for which BCS remained stable, BCS decreased for triplet-, and even more intensively for quadruplet-bearing ewes. Consequently, plasma NEFA concentrations were higher for quadruplet-bearing ewes than for twin and triplet-bearing ewes, especially during the last week prepartum. Blood BHB concentrations increased from 0.63 to 1.13 mM over time. Regardless of dietary treatments, in the last week prepartum, blood BHB concentrations increased for quadruplet-bearing ewes, being 2.6 and 2.2 times greater than for twin and triplet-bearing ewes, respectively. These results suggest that dynamic responses of energy metabolism in late gestation of prolific ewes are influenced by both dietary energy level and litter size.

Propylthiouracil thyroid manipulation positively affects the metabolic adaptability of primiparous dairy cows to early lactation requirements

The study examined effects of thyroid manipulation with propylthiouracil (PTU) on the metabolic adaptability of transitional dairy cows to early lactation. The study included 30 primiparous Holstein-Friesian cows, which were divided into two groups: PTU+ (n = 15; received orally 4 mg/kg PTU during 20 days before expected calving) and PTU− (n = 15; did not receive orally PTU). Blood was sampled from each cow consecutively from − 20, − 17, − 13, − 5, − 4, − 3, − 2, and − 1 days before the expected term of calving, calving day (0), and + 1, + 2, + 3, + 4, + 5, + 10, + 15, + 30 and + 60 days after the calving to measure thyroid stimulating hormone (TSH), triiodothyronine (T3), thyroxine (T4), insulin, glucose, beta-hydroxybutyrate (BHB), bilirubin, total protein and albumin concentrations. Liver samples were biopsied at −7 ± 2 and +7 day relative to calving from both groups of cows to determine deiodinase (DIO) expressions and fat and glycogen content. Additionally, milk yield was monitored during the first 60 days of lactation. PTU successfully induced thyroid suppression by significantly reducing T3 and T4 concentrations and hepatic DIO1 expressions and caused PTU+ cows to have significantly higher insulin and glucose concentration in the precalving period. After calving, PTU+ cows had higher insulin and glucose concentration, liver glycogen content and overall milk production, lower BHB concentration, BCS loss, and liver fat deposits. Accordingly, cows treated with PTU have a more favourable energy balance and metabolic adaptation to early lactation.

Elevated osmol gaps in patients with alcoholic ketoacidosis.

The use of the osmol gap as a surrogate marker of toxic alcohol poisoning is common. Unfortunately, many patients with alcoholic ketoacidosis have elevated osmol gaps and are misdiagnosed with toxic alcohol poisoning. We aimed to characterize the range of osmol gaps in patients with alcoholic ketoacidosis. This was a retrospective poison center study. Data from 24 years were reviewed using the following case definition of alcoholic ketoacidosis: (1) documented alcohol use disorder; (2) presence of urine or serum ketones or an elevated blood beta-hydroxybutyrate concentration; (3) an anion gap ≥14 mmol/L. Potential cases of alcoholic ketoacidosis that failed to fulfill all three criteria were adjudicated by three toxicologists. Exclusion criteria included (1) detectable toxic alcohol concentration, (2) hemodialysis and/or multiple doses of fomepizole, (3) no osmol gap documented, (4) other diagnoses that lead to a metabolic acidosis. Demographics, pH, anion gap, lactate concentration, and osmol gap were extracted. Of 1,493 patients screened, 55 met criteria for alcoholic ketoacidosis. Sixty-four percent were male, and their median age was 52 years. The median osmol gap was 27 [IQR 18-36]. The largest anion gap was 57 mmol/L, and the lowest pH was 6.8. Forty-five (82%) of the patients with alcoholic ketoacidosis had osmol gaps >10; 38 (69%) had osmol gaps >20; 24 (44%) had osmol gaps >30; 11 (20%) had osmol gaps > 40. The large range of osmol gaps in patients with alcoholic ketoacidosis often reaches values associated with toxic alcohol poisoning. The study is limited by the potential for transcribing errors and the inability to identify the cause of the osmol gap. In this retrospective study, patients with alcoholic ketoacidosis had a median osmol gap of 27. Given that alcoholic ketoacidosis is easily and inexpensively treated, proper identification may prevent costly and invasive treatment directed at toxic alcohol poisoning.

Impact of oil type and savory plant on nutrient digestibility and rumen fermentation, milk yield, and milk fatty acid profile in dairy cows

Fat supplements are well known for their multiple beneficial effects on ruminant health, reproduction and productivity, and as a source for certain bioactive compounds in ruminant products. On the other hand, numerous phytochemicals have demonstrated the potential to improve rumen fermentation through modifying the volatile fatty acid (VFA) pattern to favour those with greater energy efficiency, boosting microbial protein synthesis, and decreasing methane emission and ruminal ammonia concentration. Savory is an aromatic plant rich in various phytochemicals (mainly carvacrol and flavonoids) that can alter ruminal metabolism of dietary fatty acids, potentially increasing the production of some bioactive compounds such as conjugated linoleic acids (CLAs). This study aimed to investigate combined effects of oil type (fish oil (FO) versus soybean oil (SO)) and the inclusion of savory (Satureja khuzistanica) plant (SP) in the diet on total tract digestibility of nutrients, rumen fermentation, milk yield and milk fatty acid profile in dairy cattle. Eight multiparous lactating Holstein cows were used in a replicated 4 × 4 Latin square design experiment with four diets and four 21-d periods. During each experimental period consisted of 14 days of adaptation and a 7-day sampling period, cows were randomly assigned to one of the four dietary treatments: the diet supplemented with 2% (DM basis) fish oil (FOD) or soybean oil (SOD), the FOD or SOD plus 370 g DM/d/head SP (FODs, SODs, respectively). The experimental diets were arranged in a 2 × 2 factorial design, with the fat sources as the first and SP as the second factor. The FO-supplemented diets had lower dry matter intake (DMI) and higher total tract digestibility than SO-supplemented diets (P < 0.05), and including SP in the diet improved total tract digestibility of dry matter (DM), organic matter (OM), ether extract (EE), and non-fibrous carbohydrates (NFC) (P < 0.05) without negatively affecting DMI. Rumen pH was lower with SO than with FO diets (P < 0.01) and increased with SP inclusion in the diet (P < 0.05). Total protozoa count and ruminal ammonia concentration decreased, and the branched-chain VFA (BCVFA) proportion increased with SP inclusion in the diet (P < 0.05). Milk production, as well as the concentration and yield of milk components (except lactose concentration) were higher with SO than with FO diets (P < 0.05), but these variables remained unaffected by SP. The milk concentrations of both non-esterified fatty acids (NEFA) and beta-hydroxybutyrate (BHB) were lower with SO compared to FO diets, and these variables were reduced by SP (P < 0.01). The proportions of both mono- and polyunsaturated FA (MUFA and PUFA, respectively) in milk were higher with FO than with SO diets (P < 0.01), and their proportions increased by SP at the expense of saturated FA (SFA) (P < 0.01). Including SP in the diet increased the proportions of all the milk n-3 FA (C18:3c, C20:5, and C22:6) by 21%, 40%, and 97%, respectively, and those of conjugated linoleic acids (C18:2 (c9,t11-CLA) and C18:2 (t10,c12-CLA)) by 23% and 62%, respectively. There was no interaction between oil type and SP for the assessed variables. Fish oil, despite reducing milk production and milk components, was more effective than soybean oil in enriching milk with healthy FA. These findings also show promise for SP as a feed additive with the potential to improve total tract digestibility, rumen fermentation and milk FA composition.

Effects of Supplementing Different Quantities of Moringa stenopetala Leaves on Plasma Metabolite and Acylcarnitine Profile, Body Condition Score and Milk Yield Performance in Zebu (Bos indicus) Cattle.

The formulation of multi-nutrient blocks based on low-cost and locally available browse feed resources can be a valid feeding strategy in Sub-Saharan Africa, where inadequate feed supply, both in quality and quantity, is a major constraint. We evaluated the four different inclusion percentages (M-0%, M-25%, M-35% and M-45%) of Moringa stenopetala leaf powder to multi-nutrient blocks on their change on blood metabolite of dairy cows under practical, ranging conditions. Multi-nutrient blocks with four inclusion rates of M. stenopetala leaves were applied as complementary feed for free ranging dairy cows. The study was performed on 24 free ranging dairy cows reared around Arba Minch town in the Southern Ethiopian Rift Valley. Blood samples were collected from the jugular vein of dairy cows both before and after supplementation. Plasma glucose, beta hydroxy butyrate (BHB), urea, creatinine, triglycerides and nonesterified fatty acids (NEFA) concentration was quantified spectrophotometrically. Dried serum spots were subject to quantitative electrospray tandem mass spectrometry to estimate changes in nutrient metabolism based on selected carnitines. Based on these measurements, the milk yield and body condition score were increased during the period of multi-nutrient block supplementation. During the supplementation period, the cows got higher plasma glucose, triglyceride and urea concentrations and lower concentrations of BHB, NEFA and creatinine. From the metabolite profiles, a more efficient nutrient use could be concluded. Although no clear dose-response relationship was observed, the highest inclusion of the M. stenopetala leaves in the multi-nutrient blocks gave the best performance. This outcome supports the idea of implementing M. stenopetala based multi-nutrient blocks on tropical smallholder farms that are not easily accessible to conventional extension services.

311 Effect of feeding butyric acid on growth performance and metabolic indicators of dairy calves before weaning: A meta-analysis

Abstract This meta-analysis aimed to evaluate the effect of feeding butyric acid (BA) on growth performance and metabolic indicators in dairy calves. A literature search was conducted to identify in vivo research studies carried out on BA supplementation in dairy calves. Inclusion criteria were in vivo studies, dairy calves, weaning, BA, and inclusion doses of BA. Twenty-three papers with 80 data and 1,132 calves were selected. Data extracted included the number of calves in control and treatment groups and measures of variance of responses (standard error or standard deviation). The response variables were production performance including body weight (BW), average daily gain (ADG) feed efficiency (FE), and metabolic indicators including blood glucose and beta-hydroxybutyrate (BHB) concentrations. A random effect of model was used to examine the raw mean difference and standardized mean difference between BA supplementation and the control group. The analysis was conducted using the metafor package of Rstudio. Butyric acid moderately improved the growth performance and metabolic indicators responses of calves with substantial heterogeneity (59 &amp;lt; I2 &amp;lt; 73%, P &amp;lt; 0.01). Final BW and ADG were increased by 2.7 kg and 48.1 g/day, or &amp;gt; 0.6 and &amp;gt; 0.4 standard deviation units (P &amp;lt; 0.05), respectively. However, FE was increased by BA supplementation but not significantly different. For metabolic indicators, glucose concentration was greater with BA supplementation with &amp;gt; 0.4 standard deviation unit, (P &amp;lt; 0.05). However, BA supplementation did not affect the blood concentration of BHB (P &amp;gt; 0.05). In conclusion, the meta-analysis results demonstrated that BA constitutes an important energy source for dairy calves. Butyric acid is effective in promoting growth performance and intestinal health and, yet, increasing production profits.

Performance and metabolic evaluation in primiparous beef cows under grazing at different breeding ages.

We aimed to evaluate the metabolic and performance differences in primiparous Nellore cows, which became pregnant at 14 or 24-mo old. Thirty-eight cows with 202 ± 5 days of gestation were divided into two treatments according to breeding age: 14 or 24-mo. Cows were evaluated for body weight (BW), body condition score (BCS), carcass characteristics, milk yield, calves's performance, and blood characteristics. The animals were managed in eight paddocks under continuous grazing and evaluated from 90 d before parturition until 240 d after calving. We observed an interaction between breeding age and time (P < 0.01) for cow BW. Both breeding age categories experienced BW loss during parturition, with a concurrent decrease in BCS. However, following their first calving, the BW of 24-mo cows remained stable (P > 0.05), whereas 14-mo cows exhibited a gradual recovery in BW after parturition (P < 0.05). Milk yield was greater in 24-mo animals (P < 0.01), but decreased with increasing milking days (p < 0.05) for both groups. The weight gain calves from the heifers bred at 24-mo was greater (P < 0.01), which reflected in greater BW at weaning. The beta-hydroxybutyrate (β-OHB) concentration was greater before calving and a marked decrease after parturition (P < 0.05). The 24-mo cows had greater blood β-OHB (P < 0.01) at prepartum and 30 days after calving. Blood progesterone was greater in 24-mo cows (P > 0.05). Primiparous beef cows that conceive at either 14 or 24-months of age exhibit distinct nutritional requirements and metabolic profiles. Notably, cows that conceive at 24-months of age have the advantage of weaning heavier calves and displaying a more consistent reproductive cycle following their first calving than cows that conceive at 14-months.

The Effect of Subclinical Ketosis on the Peripheral Blood Mononuclear Cell Inflammatory Response and Its Crosstalk with Depot-Specific Preadipocyte Function in Dairy Cows.

During the periparturient period, cows undergo heightened energy demands at lactation onset, paired with reduced dry matter intake, leading to negative energy balance (NEB). Excessive lipolysis-driven adipose tissue remodeling, triggered by NEB, significantly contributes to ketosis in periparturient dairy cows. However, the role of peripheral blood mononuclear cells (PBMCs) in the pathogenesis of ketosis and in modulating adipose tissue function remains poorly understood. Here, we investigated how ketosis affects the transcriptional profile and secretome of PBMCs and its influence on preadipocyte function in visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT). Twenty-one postpartum Holstein dairy cows were categorized as either subclinical ketosis (SCK; BHB ≥ 1.0 mM) or control (CON; BHB < 0.8 mM) based on blood beta-hydroxybutyrate (BHB) concentration screening. Blood samples were collected intravenously for the isolation of PBMCs and serum metabolic profiling. Ketosis elevated circulating NEFA and BHB levels but reduced total WBC and neutrophil counts. Isolated PBMCs were evaluated for gene expression and used to produce conditioned media (PBMC-CM), during which PBMCs were stimulated with 10 ng/mL LPS. The overall phenotype of PBMCs was largely consistent between SCK and CON cows, with minimal differences detected in immunomodulatory cytokine expression and PBMC-CM composition following stimulation. Preadipocytes isolated from non-ketotic cows were treated with PBMC-CM to assess the effect of PBMC secretomes on adipose cell function. Preadipocytes treated with SCK PBMC-CM showed reduced lipid accumulation compared to those treated with CON PBMC-CM regardless of the depot. SAT preadipocytes had heightened expression of lipid metabolism-related genes, including DGAT1, LIPE, and FASN, compared to VAT when treated with SCK PBMC-CM. Preadipocytes treated with CM from PBMC stimulated by LPS exhibited upregulation in IL1B and IL6 regardless of the depot or source of PBMCs. Together, these results indicate that although PBMC profiles showed minimal differences, preadipocytes treated with PBMC-CM may be influenced by additional factors, leading to altered preadipocyte function and gene expression that may contribute to adipose cellular dysfunction.

Metabolic adaptation to lactation of dairy cows in two contrasting facilities involving partial confinement plus grazing or total confinement

Context The increasing intensification of pasture-based systems has subjected the cows to different productive environments, which could affect physiological responses and, consequently, their productive performance. Aims The aim was to determine the effect of contrasting housing facilities (outdoor soil-bedded vs compost-bedded pack barn) used in partial confinement in pasture-based systems, on the metabolic adaptation during early lactation and its impact on productive and reproductive performance of autumn- and spring-calving dairy cows, having as a positive control a zero-grazing confined system in compost barn. Methods Multiparous Holstein dairy cows that calved in autumn (n = 36) and spring (n = 48) were distributed in the following three treatments from calving to 90 days in milk (DIM): outdoor soil-bedded–grazing (OD-GRZ), compost barn–grazing (CB-GRZ), compost barn–total mixed ration (CB-TMR). Milk production, total milksolids (TMS), body condition score, non-esterified fatty acids (NEFA), beta-hydroxybutyrate (BHB), cholesterol, insulin, insulin-like growth factor-1 (IGF-1), and the proportion of cows with corpus luteum were determined in repeated measurements. Key results In both calving seasons, milk production and TMS yields did not differ between OD-GRZ and CB-GRZ, but were greater in CB-TMR (P &lt; 0.0001). In autumn, NEFA and BHB were not affected by treatments, but cholesterol increased faster in CB-TMR (P = 0.0500). In spring, NEFA and cholesterol concentrations were not affected by treatment, but BHB remained greater in OD-GRZ until 90 DIM than in the other treatments. IGF-1 and insulin did not differ between treatments in autumn, but in spring, IGF-1 was greater in CB-TMR (P &lt; 0.0001). The proportion of cows with corpus luteum was not different between pasture-based treatments, but both were greater than CB-TMR up to 40 DIM in autumn (P = 0.0489) and during the entire study in spring CB-TMR (P = 0.0285). Conclusions Although no differences were found among housing facilities in partial confinement, except that in spring OD-GRZ cows had greater BHB concentrations, confined cows prioritised milk production instead of reproductive function, despite presenting better energy indicators than did pasture-based cows. Implications Outdoor housing combined with grazing can increase the risk of greater BHB concentrations, indicative of subclinical ketosis, under heat-stress conditions, when compared with indoor housing. Confined cows increased milk production but had a delay in the resumption of ovarian cyclicity, even having a better energy status than pasture-based cows.

The impact of short-term eucaloric low- and high-carbohydrate diets on liver triacylglycerol content in males with overweight and obesity: a randomized crossover study

BackgroundIntrahepatic triacylglycerol (liver TG) content is associated with hepatic insulin resistance and dyslipidemia. Liver TG content can be modulated within days under hypocaloric conditions. ObjectivesWe hypothesized that 4 d of eucaloric low-carbohydrate/high-fat (LC) intake would decrease liver TG content, whereas a high-carbohydrate/low-fat (HC) intake would increase liver TG content, and further that alterations in liver TG would be linked to dynamic changes in hepatic glucose and lipid metabolism. MethodsA randomized crossover trial in males with 4 d + 4 d of LC and HC, respectively, with ≥2 wk of washout. 1H-magnetic resonance spectroscopy (1H-MRS) was used to measure liver TG content, with metabolic testing before and after intake of an LC diet (11E% carbohydrate corresponding to 102 ± 12 {mean ± standard deviation [SD]) g/d, 70E% fat} and an HC diet (65E% carbohydrate corresponding to 537 ± 56 g/d, 16E% fat). Stable [6,6-2H2]-glucose and [1,1,2,3,3-D5]-glycerol tracer infusions combined with hyperinsulinemic-euglycemic clamps and indirect calorimetry were used to measure rates of hepatic glucose production and lipolysis, whole-body insulin sensitivity and substrate oxidation. ResultsEleven normoglycemic males with overweight or obesity (BMI 31.6 ± 3.7 kg/m2) completed both diets. The LC diet reduced liver TG content by 35.3% (95% confidence interval: −46.6, −24.1) from 4.9% [2.4–11.0] (median interquartile range) to 2.9% [1.4–6.9], whereas there was no change after the HC diet. After the LC diet, fasting whole-body fat oxidation and plasma beta-hydroxybutyrate concentration increased, whereas markers of de novo lipogenesis (DNL) diminished. Fasting plasma TG and insulin concentrations were lowered and the hepatic insulin sensitivity index increased after LC. Peripheral glucose disposal was unchanged. ConclusionsReduced carbohydrate and increased fat intake for 4 d induced a marked reduction in liver TG content and increased hepatic insulin sensitivity. Increased rates of fat oxidation and ketogenesis combined with lower rates of DNL are suggested to be responsible for lowering liver TG. This trial was registered at clinicaltrials.gov as NCT04581421.

Butyrate- and Beta-Hydroxybutyrate-Mediated Effects of Interventions with Pro- and Prebiotics, Fasting, and Caloric Restrictions on Depression: A Systematic Review and Meta-Analysis.

To examine the butyrate- and beta-hydroxybutyrate (BHB)-modulated effects of pre- and probiotic interventions, fasting, and caloric restriction interventions, a systematic literature review was carried out with a subsequent meta-analysis. Three pre-and probiotic intervention randomized control trials (RCTs) were included in the meta-analysis. A significant increase in butyrate (standardized mean difference (SMD) [confidence interval (CI)] 0.34; [0.02-0.67]) and an improvement in depression scores (SMD [CI] 0.15, [-0.35-0.70]) through pre- and probiotic interventions were shown in the meta-analysis. The intervention duration of the included studies ranged from three days to four weeks, with the examined population being healthy adults. Butyrate was measured in either plasma or feces, and the depression score was obtained under the Swedish core affect scale, the hospital anxiety and depression scale (HADS), or the depression, anxiety, and stress scale-21 items (DASS-21). In addition to butyrate, the total SCFA concentration also seems to be positively associated with pre- and probiotic administration (SMD [CI] 0.55 [0.15-0.95]). Despite the significant short-chain fatty acid (SCFA) and butyrate concentration changes, no significant correlation between butyrate and depression or between SCFAs and depression could be shown through linear regression models. Nevertheless, the regression coefficient b1 = 1.57 (p = 0.17) for butyrate suggests a strong, positive connection between butyrate and depression. Additionally, three studies were qualitatively analyzed, examining fasting as an intervention and revealing a connection between fasting, BHB, and depression. The association between fasting, BHB, and depression or mood elevation appeared to be related to BHB concentrations, which may be due to the similar biochemical properties of BHB and butyrate. Furthermore, caloric restrictions as alternatives to fasting were proposed as potential long-term interventions.

Relationship between Neonatal Cerebral Fuels and Neurosensory Outcomes at 3 Years in Well Babies: Follow-Up of the Glucose in Well Babies (GLOW) Study

Plain Language SummaryIn the Glucose in Well babies and their later Neurodevelopment (GLOWiNg) study, we investigated whether the availability of brain fuels in healthy term babies during the first 5 days after birth was associated with their neurodevelopmental progress at 3 years of age. We had measured plasma glucose, lactate, and beta-hydroxybutyrate concentrations when the children were babies, as these are the most common brain fuels. We used the Ages and Stages questionnaire, which is completed by parents, to assess the child’s development in areas including communication, motor skills (fine and gross), and problem solving.We studied 64 families whose babies were part of the Glucose in Well Babies (GLOW) study in New Zealand. Using both structural equation modelling and linear regression, we found that even though many babies experienced episodes of low plasma glucose concentrations, there was no detectable relationship between these episodes and developmental progress at 3 years of age. We explored other factors, including glucose concentrations, total fuels available, and the duration of low glucose episodes, and found no significant associations. Our results suggest that in healthy term babies, episodes of low glucose concentrations in the first days after birth may be part of the normal metabolic transition after birth and may not have long-term implications for neurodevelopment. However, larger studies using different assessment tools are needed to confirm these findings.

Effects of Summer Heat on Adipose Tissue Activity in Periparturient Simmental Cows.

Hot climate is one of the major factors affecting the dairy industry. Heat stress could be responsible for decreased feed intake and consequently leads to alterations in energy metabolism, particularly during late pregnancy and early lactation. This study aimed to assess the effects of summer heat on adipose tissue activities during the periparturient period in Simmental cows. Two groups of cows were involved: heat-stressed cows (n = 12) that calved from June to August and thermoneutral cows (n = 12) that calved from October to December. Blood samples were taken from each cow during the periparturient period: 21 and 7 days before calving and 8, 16, 24, 32, and 40 days after calving. Glucose, beta-hydroxy butyrate (BHB), non-esterified fatty acids (NEFA), leptin (LP), and adiponectin (ADP) were measured in serum samples by commercial kits. Thermoneutral cows expressed higher degrees of lipomobilization syndrome than heat-stressed cows, indicated by significantly higher serum NEFA and BHB concentrations in the early lactation. Leptin levels were significantly decreased, while adiponectin was increased in heat-stressed cows compared to thermoneutral ones. The results indicated that heat-stressed cows during the periparturient period mobilized less fat from adipose tissue to reduce the heat generation by fatty acid oxidation.

Capsaicin as a Dietary Additive for Dairy Cows: A Meta-Analysis on Performance, Milk Composition, Digestibility, Rumen Fermentation, and Serum Metabolites.

This study aimed to evaluate the effects of dietary supplementation with capsaicin (CAP) on productive performance, milk composition, nutrient digestibility, ruminal fermentation, and serum metabolites of dairy cows using a meta-analytical approach. The database included 13 studies, from which the response variables of interest were obtained. Data were analyzed using a random effects model, and results were expressed as weighted mean differences between treatments supplemented with and without CAP. Dietary supplementation with CAP increased (p < 0.05) dry matter intake, milk yield, feed efficiency, milk fat yield, and milk fat content. However, CAP supplementation did not affect (p > 0.05) milk protein and lactose yield, milk urea nitrogen, or milk somatic cell count. Greater (p < 0.05) apparent digestibility of dry matter and crude protein was observed in response to the dietary inclusion of CAP. Likewise, supplementation with CAP increased (p < 0.05) the rumen concentration of total volatile fatty acids. In contrast, CAP supplementation did not affect (p > 0.05) ruminal pH or the ruminal concentration of ammonia nitrogen, acetate, propionate, and butyrate. In blood serum, CAP supplementation increased (p < 0.05) the glucose concentration and decreased (p < 0.05) the concentration of non-esterified fatty acids. However, CAP supplementation did not affect (p > 0.05) the serum concentration of urea and beta-hydroxybutyrate. In conclusion, capsaicin can be used as a dietary additive to improve the productive performance, milk composition, and nutrient digestibility in dairy cows and, at the same time, improve the ruminal concentration of total volatile fatty acids and serum levels of glucose and non-esterified fatty acids.

Ketone Monoester Followed by Carbohydrate Ingestion after Glycogen-Lowering Exercise Does Not Improve Subsequent Endurance Cycle Time Trial Performance.

Relative to carbohydrate (CHO) alone, exogenous ketones followed by CHO supplementation during recovery from glycogen-lowering exercise have been shown to increase muscle glycogen resynthesis. However, whether this strategy improves subsequent exercise performance is unknown. The objective of this study was to assess the efficacy of ketone monoester (KME) followed by CHO ingestion after glycogen-lowering exercise on subsequent 20 km (TT20km) and 5 km (TT5km) best-effort time trials. Nine recreationally active men (175.6 ± 5.3 cm, 72.9 ± 7.7 kg, 28 ± 5 y, 12.2 ± 3.2% body fat, VO2max = 56.2 ± 5.8 mL· kg BM-1·min-1; mean ± SD) completed a glycogen-lowering exercise session, followed by 4 h of recovery and subsequent TT20km and TT5km. During the first 2 h of recovery, participants ingested either KME (25 g) followed by CHO at a rate of 1.2 g·kg-1·h-1 (KME + CHO) or an iso-energetic placebo (dextrose) followed by CHO (PLAC + CHO). Blood metabolites during recovery and performance during the subsequent two-time trials were measured. In comparison to PLAC + CHO, KME + CHO displayed greater (p < 0.05) blood beta-hydroxybutyrate concentration during the first 2 h, lower (p < 0.05) blood glucose concentrations at 30 and 60 min, as well as greater (p < 0.05) blood insulin concentration 2 h following ingestion. However, no treatment differences (p > 0.05) in power output nor time to complete either time trial were observed vs. PLAC + CHO. These data indicate that the metabolic changes induced by KME + CHO ingestion following glycogen-lowering exercise are insufficient to enhance subsequent endurance time trial performance.

The Most Important Metabolic Diseases in Dairy Cattle during the Transition Period.

This review paper provides an in-depth analysis of three critical metabolic diseases affecting dairy cattle such as subacute ruminal acidosis (SARA), ketosis, and hypocalcemia. SARA represents a disorder of ruminal fermentation that is characterized by extended periods of depressed ruminal pH below 5.5-5.6. In the long term, dairy herds experiencing SARA usually exhibit secondary signs of the disease, such as episodes of laminitis, weight loss and poor body condition despite adequate energy intake, and unexplained abscesses usually 3-6 months after an episode of SARA. Depressed milk-fat content is commonly used as a diagnostic tool for SARA. A normal milk-fat test in Holstein dairy cows is >4%, so a milk-fat test of <3% can indicate SARA. However, bulk tank testing of milk fat is inappropriate to diagnose SARA at the herd level, so when >4 cows out of 12 and <60 days in milk are suspected to have SARA it can be considered that the herd has a problem. The rapid or abrupt introduction of fresh cows to high-concentrate diets is the most common cause of SARA. Changes in ruminal bacterial populations when exposed to higher concentrate rations require at least about 3 weeks, and it is recommended that concentrate levels increase by no more than 400 g/day during this period to avoid SARA. Ketosis, a prevalent metabolic disorder in dairy cattle, is scrutinized with a focus on its etiological factors and the physiological changes leading to elevated ketone bodies. In total mix ration-fed herds, an increased risk of mastitis and reduced fertility are usually the first clinical signs of ketosis. All dairy cows in early lactation are at risk of ketosis, with most cases occurring in the first 2-4 weeks of lactation. Cows with a body condition score ≥3.75 on a 5-point scale at calving are at a greater risk of ketosis than those with lower body condition scores. The determination of serum or whole blood acetone, acetoacetate, beta-hydroxybutyrate (BHB) concentration, non-esterified fatty acids (NEFA), and liver biopsies is considered the best way to detect and monitor subclinical ketosis, while urine or milk cowside tests can also be used in on-farm monitoring programs. Concentrations >1.0 mmol/L or 1.4 mmol/L blood or serum BHB are considered diagnostic of subclinical ketosis. The standard threshold used for blood is 1.2 mmol/L, which corresponds to thresholds of 100 mcmol/L for milk and 15 mg/dL for urine. Oral administration of propylene glycol (250-400 g, every 24 h for 3-5 days) is the standard and most efficacious treatment, as well as additional therapy with bolus glucose treatment. Hypocalcemia is a disease of adult dairy cows in which acute hypocalcemia causes acute to peracute, afebrile, flaccid paralysis that occurs most commonly at or soon after parturition. Dairy cows are at considerable risk for hypocalcemia at the onset of lactation, when daily calcium excretion suddenly increases from about 10 g to 30 g per day. Cows with hypocalcemia have a more profound decrease in blood calcium concentration-typically below 5.5 mg/dL. The prevention of parturient paresis has been historically approached by feeding cows low-calcium diets during the dry period. Negative calcium balance triggers calcium mobilization before calving and better equips the cow to respond to the massive calcium needs at the onset of lactation. Calcium intake must be limited to <20 g per day for calcium restriction to be effective. The most practical and proven method for monitoring hypocalcemia is by feeding cows an acidogenic diet for ~3 weeks before calving. Throughout the review, emphasis is placed on the importance of early diagnosis and proactive management strategies to mitigate the impact of these metabolic diseases on dairy cattle health and productivity. The comprehensive nature of this paper aims to serve as a valuable resource for veterinarians, researchers, and dairy farmers seeking a deeper understanding of these prevalent metabolic disorders in dairy cattle.

Enhancing Weaned Piglet Health and Performance: The Role of Autolyzed Yeast (Saccharomyces cerevisiae) and β-Glucans as a Blood Plasma Alternative in Diets.

The objective of this study was to evaluate the inclusion of the autolyzed yeast (AY) Saccharomyces cerevisiae with or without an immunomodulator (1,3/1,6 β-glucans) as a total/partial substitute for blood plasma (BP) in the diet of post-weaning piglets; zootechnical performance, intestinal health and microbiota, immune responses and energy metabolism were assessed. A total of 240 castrated male and female piglets, with a mean age of 22 days and mean initial weight of 5.24 ± 0.82 kg, were randomly divided into blocks of four treatments with 12 replicates. The dietary inclusions were blood plasma (BP), autolyzed yeast (AY), autolyzed yeast + immunomodulator (AYI) and 50% BP and 50% AY (BPAY). In pre-initial phase II (29-35 days), piglets fed AY showed better feed conversion (FCR = 1.358) than the piglets in the BP (1.484), AYI (1.379) and BPAY (1.442) groups, i.e., 8.49% (0.126), 1.52% (0.021) and 4.50% (0.084), respectively (p = 0.0293). In the total period (21-42 days), better FCR was observed in the AYI (1.458) group, i.e., 4.64% (0.071), 1.15% (0.017) and 4.58% (0.070), than in the BP (1.529), AY (1.475) and BPAY (1.528) groups, respectively (p = 0.0150). In piglets fed AY (n = 3) and BPAY (n = 2), there was a reduction in the number of medications, i.e., 82.35% (-14n) and 88.23% (-15n), respectively (p = 0.0001), compared with that in the BP group (n = 17). In the AY group (73.83 mg/dL), AYI group (69.92 mg/dL), and BPAY group (69.58 mg/dL), piglets exhibited increases in triglyceride levels of 79.32%, 69.83%, and 69.00%, respectively, in comparison to those in the BP group, which had triglyceride levels of 41.17 mg/dL (p = 0.0400). The beta-hydroxybutyrate concentration in the AY group (79.96 ng/μL) was lower by 31.95%, 22.64%, and 5.89% compared to the BP group (117.50 ng/μL), AYI group (103.36 ng/μL), and BPAY group (84.67 ng/μL), respectively (p = 0.0072). In the AYI group, there was modulation of the microbiota, with an increase in the relative abundance of bacteria of the genera Lactobacillus, Collinsella and Bulleidia. AY, associated or not associated with an immunomodulator, is a potential substitute for BP in diets for piglets in the nursery phase, with positive effects on immune, metabolic, and intestinal microbial performance.

Effect of postpartum drenching on plasma parameters of cows at a large-scale dairy farm.

The aim of the present study was to explore the influence of postpartum drenching with a feed additive on the plasma concentration of biochemical parameters while factoring in prepartum rumination times (RT). One hundred and sixty-one cows were fitted with a Ruminact© HR-Tag approximately 5 days before calving. Drenching and control groups were established based on calving dates. Animals in the drenched group were treated three times (Day 1/day of calving/, Day 2, and Day 3 postpartum) using a feed additive containing calcium propionate, magnesium sulphate, yeast, potassium chloride and sodium chloride mixed in approximately 25 L of lukewarm tap water. Blood samples were collected on Days 1, 2, 3, 7 and 12. Cows with below the average RT were categorised as "low rumination" and those above it as "high rumination" animals. Drenching decreased the plasma concentrations of total protein, urea and creatinine and increased the levels of alanine aminotransferase (ALT), gamma-glutamyl transferase (GGT) and chloride. Low rumination time prepartum resulted in higher concentrations of beta-hydroxybutyrate, total protein and activities of alkaline phosphatase and GGT, while it decreased the activity of ALT and the concentrations of calcium, magnesium, sodium and potassium. The day of lactation had an effect on all parameters except for potassium.

Skin-interfaced microfluidic biosensors for colorimetric measurements of the concentrations of ketones in sweat.

Ketones, such as beta-hydroxybutyrate (BHB), are important metabolites that can be used to monitor for conditions such as diabetic ketoacidosis (DKA) and ketosis. Compared to conventional approaches that rely on samples of urine or blood evaluated using laboratory techniques, processes for monitoring of ketones in sweat using on-body sensors offer significant advantages. Here, we report a class of soft, skin-interfaced microfluidic devices that can quantify the concentrations of BHB in sweat based on simple and low-cost colorimetric schemes. These devices combine microfluidic structures and enzymatic colorimetric BHB assays for selective and accurate analysis. Human trials demonstrate the broad applicability of this technology in practical scenarios, and they also establish quantitative correlations between the concentration of BHB in sweat and in blood. The results represent a convenient means for managing DKA and aspects of personal nutrition/wellness.