Ketosis In Dairy Cows Research Articles

A systematic review of the cost of ketosis in dairy cattle

A systematic review was conducted to assess the cost of ketosis in dairy cattle, and to elucidate how ketosis cost is estimated in each of the studies. Scientific papers addressing the economic impact of ketosis in dairy cows were identified through a search in 4 databases (Medline, ISI Web of Science, CAB Abstracts, and Agricola). The literature search was conducted with no restrictions on the date of study publication, publication type, or language. The methodological quality of the studies was assessed regarding study design, data collection, and analysis and interpretation of the study results. Of 531 identified records, 10 were selected, of which 9 were published from 2015 onward. Of the 10 studies reviewed, 9 report cost of a case of ketosis, and the estimates vary widely, with values ranging from €19 to €812. Two studies report ketosis cost at a farm level (€3.6-€29/cow per year). Among the studies, we observed great variation not only in the estimation models and inputs used (costs and losses associated with the disease) but also in the definition of ketosis and its prevalence or incidence figures. Moreover, the cost of ketosis was estimated for dairy farms in the United States, Canada, the Netherlands, Denmark, France, Germany, Spain, Sweden, Norway, and India. Consequently, there was great heterogeneity regarding herd characteristics, milk production, milk prices, culled cows' value, feed prices, and costs of veterinary services. Ketosis cost estimates vary as a consequence of all these aspects. Therefore, although most of the studies were well-designed and used high-quality data, the systematic approach review does not allow combination of the cost estimates of into a single figure. In conclusion, our review highlights an overall considerable economic impact of ketosis in dairy cattle. Economic prevention and mitigation strategies should be taken according to herd- and country-specific conditions. Ketosis cost figures reported in economic studies should always be considered carefully and interpreted with appropriate consideration of the inputs of the estimation, country context, and herd parameters.

EFFECT OF PROPYLENE GLYCOL ON BLOOD METABOLITES, RUMINAL AND PRODUCTIVE PARAMETERS OF GROWING-FINISHING LAMBS

<p class="Default"><strong>Background. </strong>Propylene glycol has been used successfully since the 1950’s for him acute and prophylactic treatment of ketosis in dairy cows however; its use has been poorly evaluated in beef cattle and meat sheep.<strong> Objective</strong>. Evaluate the effects of different doses of propylene glycol on the productive parameters, blood metabolites and ruminal parameters in fattening lambs. <strong>Methodology</strong>. Twenty lambs 14.70 ±0.57 kg of weigh, 2 months old, males and Katahdin-Black Belly breed, were randomly assigned to one of four treatments, a control mixed ration and an experimental diet with three different levels of propylene glycol: 1.0, 1.5 and 2.0 g/20 kg live weight/day. The effects of propylene glycol on blood metabolites, ruminal and productive parameters were assessed. <strong>Results</strong>. Propylene glycol supplementation did not affect (P>0.05) glucose, total lipids, triglycerides and cholesterol concentration as well as increased (P<0.05) the concentration of beta hydroxybutyrate. In addition, its inclusion resulted in an increase in pH and protozoa population and in a decrease of reductive activity (P<0.05). No effect was observed (P>0.05) on feed intake, weight gain and feed conversion ratio of lambs but carcass yield was improved without increasing the feeding cost of production. <strong>Implications</strong>. Propylene glycol is a viable option as an energy source in fattening lambs. <strong>Conclusion</strong>. Inclusion of PPG increased the pH and the population of ruminal protozoa, reduced the formation of ketone bodies and improved the carcass yield of lambs without increasing the meat production cost.</p>

Evaluation of intraperitoneal administration of glucose solution using in the treatment of ketosis in dairy cows

Ketosis in high‐yielding dairy cows is the most common metabolic pathology during late dryness and early lactation. This work aims to establish the possibility and effectiveness of therapy for ketosis in dairy cows through the intraperitoneal injection of a 20% glucose solution. For the experiment, on days 21‐30 of lactation, two groups of black‐and‐white cows with a β‐hydroxybutyrate level above 1.0 mmol / l were formed. Animals of the first group (n = 10) were injected four times with an interval of 24 hours intraperitoneally with 1000 ml of 20% dextrose solution. Cows of the second group (n = 10) in a similar regimen were injected dextrose intravenously. Blood for research was obtained before the start of injections, after 5, 30 minutes, 1, 2, 3 hours after the first injection of the solution, and one day and seven days after the end of therapy. It was found that a single intravenous injection of dextrose during the first 5 minutes is accompanied by an increase in the concentration of the monosaccharide in the blood by 2.2 times (from 5.1 to 11.4 mmol / L; P <0.001). The level decreases to the initial values within 1 hour, and intraperitoneal infusion does not cause hyperglycemia. A redistribution of protein fractions accompanies therapy of cows with ketosis: a decrease in the albumin‐globulin coefficient by 16.8% (P <0.05) with intraperitoneal administration and by 26.9% (P <0.01) with intravenous administration. The activity of AST after intracavitary injections of dextrose decreased by 36.5% (P <0.05). The loading of erythrocytes with substances of low and medium molecular weight was 19.4% (P <0.05) with the intraperitoneal injection. It was not observed with the intravascular route of administration. The morphological composition of blood after intravenous administration of dextrose was characterized by an increase in the level of leukocytes by 34.8% (P <0.05), a decrease in erythrocytes by 11.9% (P <0.05), hemoglobin by 11.6% (P <0, 05), hematocrit by 12.3% (P <0.05). Therapy via intraperitoneal injection did not cause pronounced changes in these parameters. The intravenous administration of glucose promoted a more rapid elimination of ketone bodies, which decreased by 2 times one day after the end of therapy (P <0.05), but after 7 days, their level began to increase again (by 21.1%). It did not have significant differences with indicators at the time of diagnosis. Intraperitoneal infusions were accompanied by a slight decrease (by 16.3%) in the level of β‐hydroxybutyrate one day after the end of therapy, followed by a pronounced decrease in the concentration of ketones by day 7 (2.3 times; P <0.01). The dynamics of fructosamine indicate that intracavitary injections do not cause glycosylation of plasma proteins, while intravenous infusions increase the values by 37.0 ‐ 39.4% (P <0.001). Thus, intraperitoneal administration of glucose during ketosis in dairy cows has a more favorable effect on the morphobiochemical composition of the blood and provides a more prolonged therapeutic effect.

Ketosis in Dairy Cows during Early Lactation - Detection in Pooled Blood Serum Samples

Background: Ketosis is the most important metabolic disease with prevalence from 15 to 45%. Ketosis is diagnosed using a metabolic profile. Due to the high prevalence, it is necessary to determine a large number of metabolic profiles within farm, which represents an additional cost, so the implementation of pooled serum in assessing the metabolic status of cows was examined. The aim of this study was to validate and evaluate the influence of the relative position (Z-score) of the value of pooled sample metabolic parameters within the known reference value of healthy cows in the detection of ketosis in herd during early lactation.Materials, Methods & Results: The experiment has been carried out using blood samples collected by puncture of coccygeal vein from 50 ketotic and 50 healthy cows. Laboratory analysis includes determination of beta-hydroxybutyrate-BHB, non-esterified fatty acids-NEFA, cholesterol-CHOL, triglycerides-TGC, glucose-GLU, albumin-ALB, total protein-TPROT, UREA, Ca, P, total bilirubin-TBIL and aspartat aminotransferase-AST. The pooled serum was made from 10 individual samples originating from 10 different cows. A serum aliquot of 0.1 mL was taken from each sample, and a 1 mL volume of pooled serum was finally formed. Three types of serum pools were made: 1) 30 pooled sample were from ketosis; 2) 30 pooled sample were from healthy cows and 3) 60 pooled samples containing mixed sera of healthy cows and cows with ketosis were made as follows: 10 pools contain 10% to 60% of ketotic cows (1/10 to 6/10 samples). Statistical analysis includes: a) difference in metabolite concentration and Z-score in pooled sample and arithmetic mean individual sample in healthy and ketotic cow, b) correlation between Z-score of pooled sample and arithmetic mean of individual sample, c) ability of Z-score of metabolite to divide ketotic from healthy cow, d) correlation between Z-score and % of ketotic cow in pooled sample; and e) calculation of 95%CI of pooled sample Z-scores for each % of ketotic cow in pools. Z-score and all analysis were calculated for each metabolic parameter. The results of the study show that the mean values and Z-scores of the pool and the calculated average value of the individual samples participating in that pool differ significantly in healthy cows and cows in ketosis, except for TPROT and Ca. A higher value and a higher Z-score were found for BHB, NEFA, UREA, TBIL and AST, and a lower value and a lower Z-score for TGC, CHOL, GLU, ALB and P in ketotic cows compared to healthy cows. The value of the Z-score of the pooled sample and the calculated mean values of individual samples participating in the pool are highly correlated with each other (coefficient of determination over 99%). Z-score of metabolites in the pooled sample can be used to distinguish healthy from ketotic cows (ROC AUC= 0.711 to 0.989), except for TPROT and Ca. The Z-score value of the pooled sample shows a linear correlation with the percentage of ketotic cows in the pool and the reference ranges of Z-scores change significantly as a function of the percentage of ketosis cows.Discussion: Modern research on the metabolic profile in cows requires obtaining a large amount of information from as few samples as possible. The advantages of using the Z-score are reflected in the following: this score does not depend on the absolute value of the metabolite, but on the position within the known population reference value, Z-score of sample and the arithmetic mean of individual samples included in the same pool are almost identical, the Z-score of these 2 groups of results is ideally correlated, the Z-score significantly correlates with the % of ketosis samples in the pooled sample. The use of pooled sample Z-score can be a useful in a herd level assessment of metabolic status and detection of ketosis as most important metabolic disease in dairy cows.Keywords: dairy cattle, ketosis, metabolic disease, metabolic profile, pooled serum, z-score, diagnostics.

β-Hydroxybutyrate inhibits apoptosis in bovine neutrophils through activating ERK1/2 and AKT signaling pathways

Ketosis in dairy cows, a common metabolic disorder during the peripartal period, is accompanied by systemic inflammation and high concentrations of blood β-hydroxybutyrate (BHB). Neutrophil apoptosis plays a key role in maintaining the balance of inflammation and functional capacity of circulating neutrophils in ketotic cows. The kinases ERK1/2 and AKT, as well as their downstream Bcl-2 family-mediated mitochondrial signaling, are important apoptosis-regulating pathways in neutrophils. The objective of our study was to investigate the effects of BHB on neutrophil apoptosis and the underlying regulatory mechanisms during ketosis. Neutrophils were isolated from 5 multiparous cows (within 3 wk postpartum) with serum BHB concentrations <0.6 mM and glucose concentrations >3.5 mM. In a series of experiments, neutrophils were treated with increasing concentrations of BHB (0, 0.6, 2, and 3 mM for 10 h) and time (0, 2, 4, 6, 8, and 10 h with 2 mM). Subsequently, a 2 mM BHB dose was used to challenge neutrophils for 8 h. Apoptosis rate of neutrophils and protein abundance of cleaved caspase 3 were lower after BHB treatment. Treatment with BHB decreased protein and mRNA abundance of the pro-apoptotic genes Bax (BAX) and Bad (BAD), whereas it increased mitochondrial membrane potential (MMP) and protein and mRNA of the anti-apoptotic genes Bcl-xL (BCL2L1) and Mcl-1 (MCL1). This indicated that a mitochondrial pathway was involved in the inhibition of neutrophil apoptosis via BHB. In addition, both SCH772984 (an inhibitor of the ERK1/2 signaling pathway) and MK-2206 (an inhibitor of the AKT signaling pathway) alleviated the BHB-induced anti-apoptotic function of the Bcl-2 family and the inhibition of MMP. Overall, our data demonstrated that high concentrations of BHB inhibit apoptosis in bovine neutrophils by activating the ERK1/2 and AKT signaling pathways. These findings provide a theoretical basis for the understanding of systemic inflammation in ketotic cows.

β-Hydroxybutyrate impairs the release of bovine neutrophil extracellular traps through inhibiting phosphoinositide 3-kinase–mediated nicotinamide adenine dinucleotide phosphate oxidase reactive oxygen species production

Ketosis in dairy cows often occurs in the peripartal period and is accompanied by immune dysfunction. High concentrations of β-hydroxybutyrate (BHB) in peripheral blood during ketosis inhibits the release of neutrophil extracellular traps (NET) and contributes to immune dysfunction. However, the mechanisms whereby BHB affects NET release remains unclear. In this study, 5 healthy peripartal dairy cows (within 3 wk postpartum) with serum BHB concentrations <0.6 mM and glucose concentrations >3.5 mM were used as blood donors. Blood samples were collected before feeding, and the isolated polymorphonuclear neutrophils were incubated with 3 mM BHB for different times. Inhibition of Cit-H3 (citrullinated histone 3) protein abundance, a marker of NET activation, in response to BHB was used to determine an optimal incubation time for in vitro experiments. Four hours was selected as the optimal duration of BHB treatment. Phorbol-12-myristate-13-acetate (PMA) was used to induce the release of NET in vitro. The BHB treatment with or without PMA treatment decreased protein abundance of Cit-H3 and PAD4 (arginine deiminase 4) and increased neutrophil elastase. Immunofluorescence and scanning electron microscope analyses revealed that BHB treatment inhibited PMA-induced NET release. The BHB treatment also decreased double strain DNA content in the supernatant, further confirming the inhibitory effect of BHB on NET release. Furthermore, BHB treatment decreased the level of intracellular reactive oxygen species (ROS), phosphorylation level of p47, and protein abundance of Rac2, suggesting that BHB-induced NET inhibition may have been caused by decreased NADPH oxidase-derived ROS. The phosphorylation level of phosphoinositide 3-kinase (PI3K), an important upstream regulator of NADPH oxidase, was attenuated by BHB treatment. To confirm the involvement of PI3K signaling pathway in BHB-induced NET inhibition, 740Y-P, a potent activator of PI3K signaling pathway, was used. Data indicated that 740Y-P relieved the inhibitory effects of BHB on ROS production and NADPH oxidase activation. Importantly, as revealed by immunofluorescence and scanning electron microscopy analyses, 740Y-P also dampened the inhibitory effect of BHB on NET release and the protein abundance of Cit-H3 and PAD4. Overall, the present study revealed that high concentration of BHB impairs NET release through inhibiting PI3K-mediated NADPH oxidase ROS production. These findings help partly explain the immune dysfunction in cows experiencing negative energy balance or ketosis in early lactation.

The Use of Multilayer Perceptron Artificial Neural Networks to Detect Dairy Cows at Risk of Ketosis.

Simple SummaryKetosis is a serious metabolic disease in high-yield dairy cows, that affects productive herds throughout the world. Subclinical ketosis is one of the most dominant metabolic disorders in dairy herds during early lactation, so early detection and prevention are important for both economic and animal welfare reasons. Neural networks, which offer a high degree of accuracy in predicting various phenomena and processes where there is no clear causal correlation or there are no rules that allow the establishment of a logical cause-and-effect relationship, can be used to address problems related to prediction, classification, or control. A Multi-Layer perceptron (MLP) is a feedforward artificial neural network model that takes input data for a set of proper output. This study investigated the performance of four algorithms used to train MLP networks. The experimental results demonstrate that the MLP network model improved the accuracy of process recognition of subclinical ketosis in dairy cows. The received artificial model’s results were saved in the predictive model markup language (PMML) and can be used to describe the learning set, the algorithm used in the data mining application and related information.Subclinical ketosis is one of the most dominant metabolic disorders in dairy herds during lactation. Cows suffering from ketosis experience elevated ketone body levels in blood and milk, including β-hydroxybutyric acid (BHB), acetone (ACE) and acetoacetic acid. Ketosis causes serious financial losses to dairy cattle breeders and milk producers due to the costs of diagnosis and management as well as animal welfare reasons. Recent years have seen a growing interest in the use of artificial neural networks (ANNs) in various fields of science. ANNs offer a modeling method that enables the mapping of highly complex functional relationships. The purpose of this study was to determine the relationship between milk composition and blood BHB levels associated with subclinical ketosis in dairy cows, using feedforward multilayer perceptron (MLP) artificial neural networks. The results were verified based on the estimated sensitivity and specificity of selected network models, an optimum cut-off point was identified for the receiver operating characteristic (ROC) curve and the area under the ROC curve (AUC). The study demonstrated that BHB, ACE and lactose (LAC) levels, as well as the fat-to-protein ratio in milk, were important input variables in the network training process. For the identification of cows at risk of subclinical ketosis, variables such as BHB and ACE levels in milk were of particular relevance, with a sensitivity and specificity of 0.84 and 0.61, respectively. It was found that the back propagation algorithm offers opportunities to integrate artificial intelligence and dairy cattle welfare within a computerized decision support tool.

Global prevalence of subclinical ketosis in dairy cows: A systematic review and meta-analysis

The objectives of this study were to estimate the global prevalence of SCK in dairy cows, to identify optimum thresholds for BHB determining, to explore heterogeneity for some particular characteristics (continents, diagnosis techniques, cut-off, sample type, parity, breed, and housing), and to determine the SCK prevalence trend. SCK prevalence levels in dairy cows from various countries were calculated using bibliographic databases up until May 17, 2021 to screen titles and abstracts for possible eligibility. Thirty-eight studies from six continents were then included using a random-effects model to calculate the pooled SCK prevalence. Subgroup meta-analyses were performed to assess the heterogeneity of the prevalence for the above characteristics. Meta-regression and cumulative meta-analysis were used to assess the SCK prevalence trends. The results showed that the global prevalence of SCK in dairy cows was 22.7% [95% CI 21.2–24.3%]. No significant differences in SCK prevalence were observed among continents, diagnostic techniques, cut-off values—≥1.0, ≥1.2 and ≥1.4 mmol/L, sample types—milk and blood, and parities. However, the prevalence in Holsteins (19.8%) was significantly lower than other mixed breeds (23.7%). The SCK prevalence was significantly higher in indoor barns (27.8%) than in pasture and unspecified housing. In meta-regression, the SCK prevalence was not associated with study years or days in milk. The cumulative evidence suggested that the prevalence of SCK in dairy cows was associated with a wide range of risk factors. This study illustrates that the global prevalence of SCK in dairy cows is quite high; therefore, there is an urgent need to globally reduce the SCK prevalence in dairy farms.

β-Hydroxybutyrate impairs neutrophil migration distance through activation of a protein kinase C and myosin light chain 2 signaling pathway in ketotic cows

Ketosis in dairy cows often occurs in the peripartal period and is accompanied by immune dysfunction. High concentrations of β-hydroxybutyrate (BHB) in peripheral blood during ketosis are closely related to the impairment of polymorphonuclear neutrophil (PMN) chemotaxis and contribute to immune dysfunction. The specific effect of BHB on PMN chemotaxis in dairy cows and the underlying molecular mechanisms are unclear. Here, 30 multiparous cows (within 3 wk postpartum) classified based on serum BHB as control (n = 15, BHB <0.6 mM) or clinically ketotic (n = 15, BHB >3.0 mM) were used. Blood samples were collected before feeding, and the isolated PMN were treated with platelet-activating factor for 0.5 h to activate their migration. Scanning electron microscopy revealed a longer tail in PMN of ketotic cows. In addition, the phosphorylation and transcription levels of myosin light chain 2 (MLC2) increased in PMN of ketotic cows. Polymorphonuclear neutrophils from control dairy cows were incubated with 3.0 mM BHB for different times in vitro, and 6 h was selected as the proper duration of BHB stimulation according to its inhibition effect on PMN migration using an under-agarose PMN chemotaxis model. Similarly, BHB stimulation in vitro resulted in inhibition of migration distance and deviation of migration direction of PMN, as well as a longer tail in morphology in the scanning electron microscope data, suggesting that BHB-induced PMN migration inhibition may be mediated by impairing the trailing edge contraction. To confirm this hypothesis, sotrastaurin (Sotra)-a specific inhibitor of protein kinase C (PKC), which is the core regulator of cell contraction-was used with or without BHB treatment in vitro. Sotra was pretreated 0.5 h before BHB treatment. Accordingly, BHB treatment increased the phosphorylation level of PKC and MLC2, the protein abundance of RhoA and rho-kinase 1 (ROCK1), and the mRNA abundance of PRKCA, MYL2, RHOA, and ROCK1 in PMN. In contrast, these effects of BHB on PMN were dampened by Sotra. As demonstrated by immunofluorescence experiments in vitro, the BHB-induced inhibition of trailing edge contraction of PMN was relieved by Sotra. In addition, Sotra also dampened the effects of BHB on PMN migration in vitro. Furthermore, as verified by in vivo experiments, compared with the control cows, both abundance and activation of PKC signaling were enhanced in PMN of ketotic cows. Overall, the present study revealed that high concentrations of blood BHB impaired PMN migration distance through inhibition of the trailing edge contraction, mediated by enhancing the activation of PKC-MLC2 signaling. These findings help explain the dysfunctional immune state in ketotic cows and provide information on the pathogenesis of infectious diseases secondary to ketosis.

USE OF BACILLUS PUMILUS FOR PREVENTION OF KETOSIS IN COWS

The paper considers the effectiveness of Bacillus pumilus (109 CFU / g) for dairy cows for the treatment and prevention of ketosis. The causes of ketosis in the farm were also studied. The research was conducted in LTD "Agrofirma Lan", v. Kindrativka, Sumy district, Sumy region. Healthy and ill on ketosis cows were used for the experiment. The total number of experimental animals was 15 heads. Animals with ketosis received compound feed with the addition of Bacillus pumilus (109 CFU / g) at a dose of 15-35 g per animal. Healthy cows in the control group had a normal diet for their production group. The studies were performed for 30 days. The aim of the study was to investigate the mechanism of acetonemia in farm animals and to determine the effectiveness of Bacillus pumilus (109 CFU / g) in ketosis of dairy cows. During the study it was found that cows at different times of the year productivity was largely related to the way they were kept. Thus, in the warm season, cows with an average daily milk yield of more than 35 kg and younger cows of the first lactation had better clinical indicators compared to other animals. According to the results of the studies, it was found that the level of urea and urea nitrogen in the cows of the experimental group before treatment was 77.8 % higher than in healthy animals in the control. Aspartate aminotransferase (AST) at the beginning of the study in cows with ketosis was 78.8 % higher than in healthy animals. An increase in the level of this metabolite in the blood indicates liver damage and increases and decreases simultaneously with urea and β-ketones in the blood of sick animals. In addition, serum protein levels, including globulins and albumins, in experimental and control cows were within the reference value for cows throughout the experimental period. Feeding cows that ill on ketosis Bacillus pumilus (109 CFU / g) at a dose of 35 g per animal helps to reduce serum β-ketones and return to physiological norm. The use of probiotic strain Bacillus pumilus does not cause toxic effects on organs and systems of the body. Contributes to the normalization of metabolic processes in the body.

Seasonal effect of milk yield and blood metabolites in relation to ketosis of dairy cows fed under a high ambient temperature.

Background and Aim:Metabolism and environment are closely related. Under high ambient temperature (HTa), dairy cows may have different energy metabolism during summer and winter. The present study was carried out to investigate the effect of HTa on the milk yield and blood concentration of beta-hydroxybutyrate (BHBA) and glucose at the herd level.Materials and Methods:One large dairy farm in Thailand with more than 100 crossbred Holstein cows milked each month was selected. The first experiment was performed on non-lactating cows to determine the normal daily concentrations of blood BHBA and glucose. Under the HTa condition, there was no significant change in blood BHBA and glucose concentrations. The second experiment was performed using a prospective cohort clinical design to demonstrate the seasonal effect on milk yield and blood BHBA as an indication of energy metabolism at the herd level.Results:The temperature and humidity index for the winter (78.1±0.5) and summer (83.4±0.7) periods differ significantly. The average milk yield during the winter period was 17.8% higher than during the summer period. The reduction of body condition score (BCS) during early lactation was significant in the winter cows. Both higher milk yield and lower BCS in the winter cows suggested a state of negative energy balance. However, there was no difference in blood BHBA and glucose concentrations between winter and summer cows. The effect of HTa on insulin signaling appeared to be a counterbalancing factor for the ketogenic status. Based on the present results, it would be interesting to further investigate the incidence of subclinical and clinical ketosis in a dairy farm under tropical conditions.Conclusion:The present experiment revealed that HTa during summer decreased milk yield in dairy cows fed under tropical conditions. Higher milk yield in winter caused a greater reduction of BCS and suggested a greater negative energy balance. However, there was no seasonal effect on blood BHBA and glucose concentrations.

Dietary supplementation with rumen-protected capsicum during the transition period improves the metabolic status of dairy cows

In ruminants, it has been observed that capsicum oleoresin can alter insulin responses and that high-intensity artificial sweetener can increase glucose absorption from the small intestine. Because glucose metabolism and insulin responses are critical during early lactation, these supplements might have an effect on the metabolic status of dairy cows during the transition period. The objective of this experiment was to evaluate the effects of rumen-protected capsicum oleoresin fed alone or in combination with artificial sweetener during the transition period on lactational performance and susceptibility to subclinical ketosis in dairy cows. Fifteen primiparous and 30 multiparous Holstein cows (a total of 39 cows finished the study) were arranged in a randomized complete block design during d -21 to 60 relative to parturition. Cows within block were randomly assigned to one of the following treatments: no supplement (CON), supplementation with 100 mg of rumen-protected capsicum/cow per day (RPCap), or RPCap plus 2 g of high-intensity artificial sweetener/cow per day (RPCapS). For both the RPCap and RPCapS treatments, only rumen-protected capsicum was fed during the dry period. From d 8 to 11 of lactation, intake was limited to 70% of predicted dry matter intake to induce subclinical ketosis. Production variables were recorded daily, samples for milk composition were collected on wk 2, 4, 6, and 8, and blood samples were collected on wk -2, 1, 2, and 4 of the experiment for analysis of metabolic hormones and blood cell counts. Supplementation with rumen-protected capsicum increased serum insulin and decreased β-hydroxybutyrate concentrations precalving, indicating a decrease in lipolysis. During the lactation period, RPCap was associated with a trend for increased milk production and feed efficiency following the ketosis challenge. Supplementation with RPCapS appeared to negate the response to rumen-protected capsicum. All cows developed subclinical ketosis during the challenge, and this was not affected by treatment. We conclude that treatments did not decrease susceptibility to subclinical ketosis; however, dietary supplementation with rumen-protected capsicum was effective at improving energy status precalving and tended to increased milk production and feed efficiency. The mechanism underlying these responses is unclear.

Predicting Subclinical Ketosis in Dairy Cows Using Machine Learning Techniques

Simple SummaryThe maintenance of cows in good health and physical condition is an important component of dairy cattle management. One of the major metabolic disorders in dairy cows is subclinical ketosis. Due to financial and organizational reasons it is often impossible to test all cows in a herd for ketosis using standard blood examination method. Using milk data from test-day records, obtained without additional costs for breeders, we found diagnostic models identifying cows-at-risk of subclinical ketosis. In addition, to select the best models, we present a general scoring approach for various machine learning models. With our models, breeders can identify dairy cows-at-risk of subclinical ketosis and implement appropriate management strategies and prevent losses in milk production.The diagnosis of subclinical ketosis in dairy cows based on blood ketone bodies is a challenging and costly procedure. Scientists are searching for tools based on results of milk performance assessment that would allow monitoring the risk of subclinical ketosis. The objective of the study was (1) to design a scoring system that would allow choosing the best machine learning models for the identification of cows-at-risk of subclinical ketosis, (2) to select the best performing models, and (3) to validate them using a testing dataset containing unseen data. The scoring system was developed using two machine learning modeling pipelines, one for regression and one for classification. As part of the system, different feature selections, outlier detection, data scaling and oversampling methods were used. Various linear and non-linear models were fit using training datasets and evaluated on holdout, testing the datasets. For the assessment of suitability of individual models for predicting subclinical ketosis, three β-hydroxybutyrate concentration in blood (bBHB) thresholds were defined: 1.0, 1.2 and 1.4 mmol/L. Considering the thresholds of 1.2 and 1.4, the logistic regression model was found to be the best fitted model, which included independent variables such as fat-to-protein ratio, acetone and β-hydroxybutyrate concentrations in milk, lactose percentage, lactation number and days in milk. In the cross-validation, this model showed an average sensitivity of 0.74 or 0.75 and specificity of 0.76 or 0.78, at the pre-defined bBHB threshold 1.2 or 1.4 mmol/L, respectively. The values of these metrics were also similar in the external validation on the testing dataset (0.72 or 0.74 for sensitivity and 0.80 or 0.81 for specificity). For the bBHB threshold at 1.0 mmol/L, the best classification model was the model based on the SVC (Support Vector Classification) machine learning method, for which the sensitivity in the cross-validation was 0.74 and the specificity was 0.73. These metrics had lower values for the testing dataset (0.57 and 0.72 respectively). Regression models were characterized by poor fitness to data (R2 < 0.4). The study results suggest that the prediction of subclinical ketosis based on data from test-day records using classification methods and machine learning algorithms can be a useful tool for monitoring the incidence of this metabolic disorder in dairy cattle herds.

The Use of Monensin for Ketosis Prevention in Dairy Cows during the Transition Period: A Systematic Review.

Simple SummaryThe use of a controlled-release capsule of monensin for the prevention of ketosis in dairy cows, nowadays, has become widespread. In Europe, this is the only use of monensin permitted in dairy cows. Literature regarding the use of this molecule as a feed additive or controlled-release capsule is extensive, and results reported across studies vary with respect to the mode and dose of administration, target animals, and period of lactation. Therefore, the aim of this review was to summarize the literature observations regarding the use of monensin for the prevention of ketosis in dairy cows during the transition period.Since the approval by the European Medicines Agency in 2013 of a monensin controlled-release capsule (CRC) for the prevention of ketosis in dairy cows, there has been widespread use across Europe. In recent decades, several papers have investigated the effects of monensin used as a CRC or as a feed additive to improve cattle energy metabolism and improve feed efficiency. Since the CRC is the only form of monensin permitted in Europe in dairy cows, the objective of this review was to report and summarize observations from the literature on the effects of this treatment in transition cows. The peer-reviewed literature published from 1997 was scanned, and papers written in English were evaluated for eligibility. Only papers evaluating the use of monensin in dairy cows for the prevention of ketosis during the transition period were reviewed. In total, 42 papers met the required criteria and were included in this review. The major findings focused on cow metabolism and health, rumen fermentation and milk production and quality. Overall, the review of the existing literature confirmed that monensin delivered as a CRC during the transition period has effects of different magnitude compared to other forms, doses or durations of administration. Studies agree on the antiketotic effects of this treatment, showing evidence of an increased propionate production in the rumen, reduced blood β-hydroxybutyrate, and improved liver function in treated cows, mainly resulting in reduced incidence of peripartum disease. On the contrary, the effects of CRC on ammonia production and rumen microflora are less robust than those reported for other forms. Of importance for the European market is the well-documented absence of any negative impact on milk and cheese production and composition using the CRC treatment.

Elucidation of the mechanism of NEFA-induced PERK-eIF2α signaling pathway regulation of lipid metabolism in bovine hepatocytes

During the periparturient transition period, negative energy balance (NEB) characterized by high concentrations of non-esterified fatty acids (NEFA) may cause fatty liver and ketosis in dairy cows. Previous studies have shown that the protein kinase R-like endoplasmic reticulum kinase (PERK) branch of the endoplasmic reticulum stress (ERS) response plays an important role in lipid metabolism in hepatocytes. This study, therefore, investigated the role of the PERK-branch in NEFA-induced fatty liver. Different concentrations of NEFA or GSK2656157 (a novel catalytic inhibitor of PERK) were used to treat hepatocytes isolated from calves. The NEFA treatment significantly increased the triacylglycerol (TG) content, the phosphorylation level of PERK and eukaryotic initiation factor 2α (eIF2α), and the abundance of glucose-regulated protein 78 (Grp78), C/EBP homologous protein (CHOP), sterol regulatory element-binding protein 1c (SREBP-1c), fatty acid synthase (FASN), peroxisome proliferator-activated receptor-α (PPARα), carnitine palmitoyltransferase 1A (CPT1A), apolipoprotein B (APOB), and the low-density lipoprotein receptor (LDLR). Compared with the 1.2 mM NEFA group, inhibition of PERK activity further increased the TG content in hepatocytes, the very-low-density lipoprotein (VLDL) content in the supernatant and the protein abundance of APOB while reducing the expression and nuclear levels of SREBP-1c and PPARα, as well as the expression of CPT1A and CPT2. In conclusion, the results showed that the NEFA-induced PERK-eIF2α signaling pathway promotes lipid synthesis, lipid oxidation, but inhibits the assembly and secretion of VLDL. Therefore, during the transition period, the activation of the PERK-eIF2α signaling pathway in the liver of dairy cows could defeat the acid-induced lipotoxicity and provide energy to alleviate NEB.

EVALUATION OF DIAGNOSTIC METHODS FOR SUBCLINICAL KETOSIS IN DAIRY COWS

The article presents the results of a study of the sensitivity and specificity of two types of ketone test strips for detecting latent ketosis in dairy cows. During the experiment, test strips KetoPHAN and Keto-Test, showing the number of ketone bodies in milk and urine, were used in 108 Holstein-Friesian cows for 2-15 days after calving. Blood, urine and milk samples were taken simultaneously from the same cows. In general, subclinical ketosis in cows was determined by the level of beta-hydroxybutyrate in blood plasma by an enzymatic method («gold standard» method). The sensitivity and specificity of the test tests were evaluated at various levels of β-hydroxybutyrate. The maximum level of subclinical ketosis in cows was calculated as a β-hydroxybutyrate concentration of 1.2 mmol / L or higher. When evaluating test strips on urine and milk samples, the best results were obtained in the β-hydroxybutyrate range of 1.4 mmol / L and above. In this range, the sensitivity of the test strips to urine was high (95%), the specificity was moderate (70%). The sensitivity and specificity of milk tests were high (90% and 96%, respectively). The prevalence of subclinical ketosis in cows was studied using an electronic device (FreeStyle Optium). The prevalence of latent ketosis was different: FreeStyle - 25.0%, KetoPHAN - 48.1%, Keto-Test - 13.1%. The data obtained from the electronic device is close to the data obtained according to the "gold standard" (22.2%). Although milk and urine test strips are optimal for the diagnosis of subclinical ketosis at a plasma β-hydroxybutyrate level of 1.4 mmol / L, they can be used to predict and control ketosis in dairy cows due to their simplicity and availability.

Rumination time as an early predictor of metritis and subclinical ketosis in dairy cows at the beginning of lactation: Systematic review-meta-analysis

Daily rumination time (RT; min/d) is recognized as an important tool for assessing the health of dairy cows, which may depend on the disease, lactation stage and individual cows. Using a systematic review-meta-analysis, this study evaluated whether the variation in RT is effective for early detection of metritis and subclinical ketosis (SCK) in dairy cows in the pre and post-partum periods (from three weeks before to three weeks after calving). The research was carried out in four electronic databases - Scopus, Science Direct, Pubmed and Web of Science. The main inclusion criteria were original research; evaluation of RT in dairy cows; and use of RT for early identification of metritis and/or SCK in post-partum dairy cows. A random effect meta-analysis (MA) was conducted for each disease (metritis and SCK) separately, with the RT means of healthy and sick groups, measured in the pre and post-partum. The effect size used was the mean difference (MD).Twenty-two trials from six studies were included in the MA, involving 1494 dairy cows. For metritis, four trials from three studies in the pre-partum period were considered as well as five trials from four studies in the post-partum. For SCK, six trials from four studies pre-partum and seven trials from five studies in the post-partum period were taken into consideration. The heterogeneity between studies for metritis was null (I2 = 0%) and low (I2 = 5.7 %) in the pre-partum and in the post-partum, respectively. The MD of RT between healthy cows and those with metritis was different in the pre (MD =0.411 min/d; P < 0.001) and in the post-partum (MD =0.279 min/d; P < 0.001). In SCK, heterogeneity was high in the pre (I2 = 69 %) and in the post-partum (I2 = 58.1 %), and the MD of RT was similar between healthy and sick cows (P> 0.05). In a meta-regression, RT from primiparous cows showed a lower predicted value for MD (0.48 min. d; P < 0.05) compared to multiparous cows, and the increment in each unit of milk production decreased the predicted MD value by 0.08 min. d (P < 0.001). Our MA demonstrates that RT is a good predictor for early detection of metritis in pre and post-partum; however, it is not an adequate predictor for SCK. Further investigations using more frequent blood sampling and the same threshold values for BHB are required to assess the adequacy of rumination time to predict SCK.

Addition of straw to the early-lactation diet: Effects on feed intake, milk yield, and subclinical ketosis in Holstein cows

This study evaluated feed intake, milk yield, and subclinical ketosis in dairy cows in early lactation fed 2 different diets postpartum. Cows are typically offered a high-energy ration immediately after calving. We compared a conventional high-energy total mixed ration (TMR) with a transition ration that contained chopped straw. We predicted that adding chopped straw would increase dry matter intake, milk production, and indicators of energy metabolism during the first 3 wk of lactation compared to cows fed a conventional high-energy TMR. We also predicted that carryover effects would be likely for at least 2 wk after treatment ended. A total of 68 mixed-age Holstein cows were enrolled in the study 3 wk before their expected calving. All cows were managed on a single high-forage diet during the dry period. At calving, cows were allocated to 1 of the 2 diets: half to the conventional high-energy TMR (CTMR; n = 34; net energy for lactation = 1.61 Mcal/kg; neutral detergent fiber = 31.7%), and the other half to a high-forage TMR containing chopped wheat straw, equivalent to 4.27% dry matter (STMR; n = 34; net energy for lactation = 1.59 Mcal/kg; neutral detergent fiber = 33.7%) for 3 wk after calving. Cows on STMR were then shifted to CTMR for the next 2 wk to study short-term residual effects on the performance of cows. Treatments were balanced for parity, body condition score, and body weight. Feed intake was measured daily from 2 wk before to 5 wk after calving using automatic feed bins. Blood was sampled twice weekly from 2 wk before to 5 wk after calving, and β-hydroxybutyrate and glucose were measured in serum samples. Subclinical ketosis was identified using a threshold of β-hydroxybutyrate ≥1.0 mmol/L in wk 1 after calving and ≥1.2 mmol/L in wk 2 to 5 after calving. Cows were milked twice daily, and weekly samples (composite samples of morning and afternoon milkings) were analyzed to determine total solids, fat, protein, lactose, and somatic cell count. Data were analyzed in 2 separate periods: the treatment phase (wk +1, +2, and +3) and the post-treatment phase (wk +4 and +5). The addition of straw to the TMR negatively affected the dry matter intake of STMR cows during wk 2 and 3 of lactation. Daily milk yield during the first 5 wk of lactation was lower in STMR cows than in CTMR cows. Concentrations of β-hydroxybutyrate were higher in CTMR cows than in STMR cows during wk 1, but this effect was reversed during wk 2 and 3 of lactation. By 21 d in milk, STMR cows had a greater risk of developing subclinical ketosis than CTMR cows. Adding chopped wheat straw to the TMR during the first 21 d after calving lowered dry matter intake and provided no metabolic or production benefits to lactating dairy cattle.

Expert opinion as priors for random effects in Bayesian prediction models: Subclinical ketosis in dairy cows as an example.

Random effects regression models are routinely used for clustered data in etiological and intervention research. However, in prediction models, the random effects are either neglected or conventionally substituted with zero for new clusters after model development. In this study, we applied a Bayesian prediction modelling method to the subclinical ketosis data previously collected by Van der Drift et al. (2012). Using a dataset of 118 randomly selected Dutch dairy farms participating in a regular milk recording system, the authors proposed a prediction model with milk measures as well as available test-day information as predictors for the diagnosis of subclinical ketosis in dairy cows. While their original model included random effects to correct for the clustering, the random effect term was removed for their final prediction model. With the Bayesian prediction modelling approach, we first used non-informative priors for the random effects for model development as well as for prediction. This approach was evaluated by comparing it to the original frequentist model. In addition, herd level expert opinion was elicited from a bovine health specialist using three different scales of precision and incorporated in the prediction as informative priors for the random effects, resulting in three more Bayesian prediction models. Results showed that the Bayesian approach could naturally take the clustering structure of clusters into account by keeping the random effects in the prediction model. Expert opinion could be explicitly combined with individual level data for prediction. However in this dataset, when elicited expert opinion was incorporated, little improvement was seen at the individual level as well as at the herd level. When the prediction models were applied to the 118 herds, at the individual cow level, with the original frequentist approach we obtained a sensitivity of 82.4% and a specificity of 83.8% at the optimal cutoff, while with the three Bayesian models with elicited expert opinion, we obtained sensitivities ranged from 78.7% to 84.6% and specificities ranged from 75.0% to 83.6%. At the herd level, 30 out of 118 within herd prevalences were correctly predicted by the original frequentist approach, and 31 to 44 herds were correctly predicted by the three Bayesian models with elicited expert opinion. Further investigation in expert opinion and distributional assumption for the random effects was carried out and discussed.

Metabolomic and Proteomic Profiles Associated With Ketosis in Dairy Cows.

Ketosis is a common metabolic disease in dairy cows during early lactation. However, information about the metabolomic and proteomic profiles associated with the incidence and progression of ketosis is still limited. In this study, an integrated metabolomics and proteomics approach was performed on blood serum sampled from cows diagnosed with clinical ketosis (case, ≥ 2.60 mmol/L plasma β-hydroxybutyrate; BHBA) and healthy controls (control, < 1.0 mmol/L BHBA). Samples were taken 2 weeks before parturition and 2 weeks after parturition from 19 animals (nine cases, 10 controls). All serum samples (n = 38) were subjected to Liquid Chromatography-Mass Spectrometry (LC-MS) based metabolomic analysis, and 20 samples underwent Data-Independent Acquisition (DIA) LC-MS based proteomic analysis. A total of 97 metabolites and 540 proteins were successfully identified, and multivariate analysis revealed significant differences in both metabolomic and proteomic profiles between cases and controls. We investigated clinical ketosis-associated metabolomic and proteomic changes using statistical analyses. Correlation analysis of statistically significant metabolites and proteins showed 78 strong correlations (correlation coefficient, R ≥ 0.7) between 38 metabolites and 25 proteins, which were then mapped to pathways using IMPaLA. Results showed that ketosis altered a wide range of metabolic pathways, such as metabolism, metabolism of proteins, gene expression and post-translational protein modification, vitamin metabolism, signaling, and disease related pathways. Findings presented here are relevant for identifying molecular targets for ketosis and biomarkers for ketosis detection during the transition period.