Subclinical Ketosis Research Articles

Associations between motion activity, ketosis risk and estrus behavior in dairy cattle

Ketosis (acetonaemia) is a metabolic disorder that occurs in cattle when energy demand exceeds energy intake and results in a negative energy balance. The course of the disease often starts with a subclinical phase, so early detection is crucial for decisive strategies. The aim of this study was to determine whether daily motion activity could be used as an indicator of subclinical ketosis in early lactation and to evaluatethe effect of subclinical ketosis on activity at estrus.The study was carried out on a 75-cow dairy farm over 6 months. Data were collected from 48 cows between day 0 and day 70 post-partum. Beta-Hydroxybutyrate (BHB) concentrations were evaluated in milk samples using rapid on-site ketosis tests. A test was considered positive at a concentration of >100 μmol/l. The animals were divided into two groups: group ‘Healthy’ (H) and group ‘Ketosis’ (K). Once the on-site test was positive, the cows were assigned to group K. Progesterone concentrations were evaluated in milk by photometric detection of the colour reaction of a competitive, heterologous enzyme immunoassay (EIA). Each drop from ≥0.3 ng/ml to <0.3 ng/ml with a subsequent increase to ≥0.3 ng/ml was considered estrus. Daily milk yield, concentrate intake and motion activity were recorded from a computerized dairy management system with the associated software (DairyPlan C21).Animals in group K had lower average daily activity levels than animals in group H. In this study, statistically significant reduced motion activity in animals in group K was observed on days 6–12 post-partum (P < 0.001, χ² test) compared with the herd mean daily motion activity. Furthermore, a significant association could be found between motion activity and group affiliation (logistic regression models). The sensitivity of the detection of cows at risk for ketosis was 81.8 %, and the specificity was 65.4 %, retrospectively determined by their activity behaviour. The mean motion activity on the day of estrus was significantly (P < 0.05) lower in animals in group K than in those in group H.This method may help to establish a future early warning system for the risk of ketosis in dairy cows. Thus, cows at risk may be identified for further targeted diagnostics and for selective treatment procedures. This study confirms the already reported lasting effect of subclinical ketosis on reproductive efficiency.

Prevalence of subclinical and clinical ketosis in cattle in and around Bikaner

ABSTRACT The present study surveyed that the prevalence of subclinical and clinical ketosis in cattle was assessed in and around Bikaner; a total of 200 cows after parturition were examined. The overall prevalence of clinical ketosis amongst post-parturient cows was 11.50%, while 23.50% for subclinical ketosis. Prevalence of clinical and subclinical ketosis in cows with relation to breed was the highest in Holstein Friesian crossbred cows (17.58%), while the lowest in Rathi cows (05%). Prevalence in relation to the age was the highest in 8–9 years of age (13.79% and 29.31%) and the lowest in >9 years of age (4.76% and 9.52%). Prevalence in relation to number of lactation/calving was the highest in fourth lactation (14.29% and 30.36%) and the lowest in first lactation (2.86% and 11.43%). Out of 11.50% cases of clinical ketosis, the highest prevalence was recorded (30.43%) during 8–14 days of lactation; similarly, out of 23.50% cases of subclinical ketosis, the highest prevalence was recorded (29.79%) during 8–14 days of lactation. Month-wise prevalence of clinical and subclinical ketosis was the highest in December that is 26.09% and 23.40%, while the lowest in August 4.35% and 2.13%.

Serum vitamin D concentrations at dry-off and close-up predict increased postpartum urine ketone concentrations in dairy cattle

Vitamin D is commonly supplemented to dairy cows as vitamin D3 to support calcium homeostasis and in times of low sunlight exposure. Vitamin D has beneficial immunomodulatory and anti-inflammatory properties. Serum 25-hydroxyvitamin D [25(OH)D] concentrations fluctuated during lactation, with the lowest concentrations measured in healthy cows within 7 d of calving. However, it is unknown if serum 25(OH)D concentrations measured during the previous lactation are associated with transition diseases or health risk factors in dairy cattle. We collected serum samples from 279 dairy cattle from 5 commercial dairy herds in Michigan at dry-off, close-up, and 2-10 d in milk (DIM). Vitamin D concentrations were determined by measuring serum 25(OH)D by radioimmunoassay. Total serum calcium was measured by colorimetric methods. Body condition scores (BCS) were assigned at the time of blood collection. Clinical disease incidence was monitored until 30 d postparturition. Separate bivariable logistic regression analyses were used to determine if serum 25(OH)D at dry-off, close-up, and 2-10 DIM was associated with various clinical diseases including mastitis, lameness, and uterine disorders (classified as metritis, retained placenta, or both) and increased urine ketone concentrations at P < 0.05. Among all significant bivariable analyses, multivariable logistic regression analyses were built to adjust for potential confounding variables including parity, BCS, season, and calcium. Receiver operator characteristic (ROC) curve analyses were used to determine optimal concentrations of serum 25(OH)D. We found that higher serum 25(OH)D concentrations at dry-off and close-up predicted increased urine ketone concentrations in early lactation, even after adjustment for confounders. Alternatively, we found that lower serum 25(OH)D at 2-10 DIM was associated with uterine diseases. Optimal concentrations for serum 25(OH)D at dry-off and close-up for lower risk of increased urine ketone concentrations were below 103.4 and 91.1 ng/mL, respectively. The optimal concentration for serum 25(OH)D at 2-10 DIM for uterine diseases was above 71.4 ng/mL. These results indicate that serum 25(OH)D at dry-off and close-up may be a novel predictive biomarker for increased urine ketone concentrations during early lactation. Increased urine ketone concentrations are not necessarily harmful or diagnostic for ketosis but do indicate development of negative energy balance, metabolic stress, and increased risk of early lactation diseases. Predicting that dairy cattle are at increased risk of disease facilitates implementation of intervention strategies that may lower disease incidence. Future studies should confirm these findings and determine the utility of serum 25(OH)D concentrations as a predictive biomarker for clinical and subclinical ketosis.

Comparative study of “partial dietary cation-anion difference” strategy as a nutritional intervention for preventing subclinical hypocalcemia in dairy cattle

Two experiments were carried out in order to evaluate the efficacy of a partially decreased dietary cation-anion difference (pDCAD) of dry period rations of dairy cattle ((DCAD ~ 0 mEq/Kg DM) in prevention of postpartum subclinical hypocalcemia (SCH). The primary goal of the Experiment I was to compare the efficacy of a pDCAD strategy in minimizing SCH against a full DCAD (fDCAD ~ − 50 mEq/Kg DM) and a low calcium diet (LCD) in late (21 days (d)) pregnancy in Farm 1, using 66 multiparous cows (parity ≥ 3). The primary goal of Experiment II was to evaluate the effect of extension of a pDCAD to whole dry period (expDCAD-60 days), enrolling 40 cows (parity ≥ 3) to compare a pDCAD vs. expDCAD strategy. In both experiments, a primiparous heifers group was included as well. Serum Ca, Pi, Mg, and energy status indicators β-hydroxybutyrate (BHB) and non-esterified fatty acids (NEFA) were monitored pre- and post-partum, serially. Experiment I showed a significantly lower Ca, a numerically higher prevalence of SCH, and significantly lower NEFA and BHB in pDCAD vs. fDCAD. The prevalence of subclinical ketosis (SCK) was significantly higher in fDCAD peripartally. In Experiment II, a significantly higher Ca and lower prevalence of SCH were observed in expDCAD vs. pDCAD postpartum, while BHB, NEFA, and the prevalence of SCK were not significantly different. The prevalence of SCH in primiparous heifers in both experiments was about 30%. Overall, compared to common ordinary fDCAD strategy, pDCAD could be potentially regarded as a practical intervention, when the adverse effects of fDCAD are unavoidable.

The relationship between transition period diseases and lameness, feeding time, and body condition during the dry period

In this longitudinal study, we tested the hypothesis that cows that are lame around dry-off are at increased risk of transition diseases (TD), including metritis, subclinical ketosis (SCK), retained fetal membranes, hypocalcemia, or displaced abomasum. We also hypothesized that the relationship between lameness and TD would be mediated through reduced feeding time. We enrolled 461 cows at 9 wk before their expected calving date on 6 commercial freestall farms in the lower Fraser Valley, British Columbia, Canada. Cows were gait-scored weekly using a scale of 1 to 5. Lameness status was classified based on consecutive gait scores as lame (2 consecutive gait scores = 3 or 1 score ≥4) or sound (2 consecutive gait scores ≤2). Lameness status was summarized as (1) lameness at dry-off (sound or lame); (2) lameness group (always sound = sound on all visits, chronically lame = lame on all visits, and other = changed from sound to lame or vice versa); and (3) proportion of weeks lame during the dry period. Body condition scores were recorded at dry-off and at calving and collectively used to calculate change in body condition for each cow. A subsample of cows (n = 159) was evaluated for feeding time once a week during the dry period. All cows were evaluated for SCK (positive = β-hydroxybutyrate ≥1.2 mmol/L) and metritis (positive = foul smell, red/brown watery vaginal discharge) every 3 to 4 d between d 3 and 17 after calving. We retrieved data on treatment of retained fetal membranes, hypocalcemia, and displaced abomasum during the first 17 d after calving, cow parity, and milk production in the previous lactation from farm records. We created a binary variable, TD (any of SCK, metritis, retained fetal membranes, hypocalcemia, or displaced abomasum), to differentiate between healthy cows and cows that developed TD. Lameness at dry-off was associated with the occurrence of metritis and TD, but not with SCK. Cows that were chronically lame and cows that had an increased proportion of weeks lame during the dry period had higher occurrence of metritis and TD. Lameness was also associated with reduced feeding time, which in turn was associated with increased likelihood of SCK and TD, but not with metritis. Lameness was not associated with change in body condition; however, cows that lost body condition score during the dry period had increased odds of developing SCK, metritis, and TD. Change in body condition was highly associated with body condition score at dry-off. These results suggest that association between lameness and TD is partially mediated through reduced feeding time.

Short communication: Effects of butyrate supplementation on the productivity of lactating dairy cows fed diets differing in starch content

The objective of this study was to evaluate the effects of butyrate supplementation on the dry matter intake (DMI), milk production, and blood metabolites of lactating dairy cows fed diets differing in starch content. Eight Holstein cows after peak lactation (58.6 ± 9.96 d in milk; mean ± SD) were blocked by parity and assigned to 1 of 2 Latin squares (4 × 4) balanced for carryover effects with a 2 × 2 factorial arrangement of treatments. Treatments differed by dietary starch content (20.6 vs. 27.5%) and butyrate supplementation (butyrate vs. control) with 21-d periods. Experimental diets contained 36 and 30% corn silage, 18 and 15% grass silage, and 46 and 55% concentrates, respectively, for low starch and high starch diets, on a dry matter (DM) basis. Butyrate was provided as Gustor BP70 WS (Norel S.A., Madrid, Spain), containing 70% sodium butyrate and 30% fatty acid mixture, at 2% of dietary DM (providing butyrate at 1.1% of dietary DM), and control premix contained 70% wheat bran and 30% fatty acid mixture. Interaction effects between dietary starch content and butyrate supplementation were not observed for primary response variables, and milk yield was not affected by treatment. Butyrate supplementation increased serum β-hydroxybutyrate concentration compared with control (0.706 vs. 0.930 mM), but did not exceed 1.2 mM, a commonly accepted value for subclinical ketosis, and DMI was not affected. Cows fed butyrate had increased milk fat content (4.58 vs. 4.37%) and milk fat yield (1.51 vs. 1.42 kg/d), tended to have increased 4% fat-corrected milk yield (35.9 vs. 34.3 kg/d) and feed efficiency (1.56 vs. 1.50; 4% fat-corrected milk yield/DMI), and had decreased milk urea nitrogen (MUN) concentration (10.8 vs. 11.7 mg/dL) compared with control. Cows fed high starch diets tended to have increased DMI (23.3 vs. 22.5 kg/d), increased milk protein yield (1.13 vs. 1.05 kg/d), and decreased MUN concentration (10.3 vs. 12.2 mg/dL). Inclusion of butyrate at 1.1% of dietary DM increased milk fat production and decreased MUN concentration without affecting DMI or increasing the risk of subclinical ketosis, regardless of dietary starch content.

Effects of dietary clinoptilolite supplementation on β-hydroxybutirate serum level and milk fat to protein ratio during early lactation in Holstein-Friesian cows

Abstract The aim of the study was to determine effects of dietary clinoptilolite (CPL) supplementation on β-hydroxybutirate (BHB) serum levels and milk fat to protein ratio (FPR) during early lactation in Holstein-Friesian cows. Seventy cows of the Holstein-Friesian breed, aged from 3 to 5 years, kept in a farm nearby Đurđevac, Croatia, were used in the study. The cows were randomly assigned into two groups, either test, in-feed CPL treated; CPL (n = 35) or control, non-treated group; CON (n = 35). The CPL group received 50 g of natural modified CPL preparation in the ratio for dairy cows, twice a day, from third month of pregnancy. Blood and milk samples were collected from the cows after parturition on days 7, 12, 19, 26 and 33 of lactation. The average value of BHB was higher in the CON than in the CPL group (1.03 ± 0.78 vs. 0.82 ± 0.42 mmol/L), as well as average value of FPR (1.32 ± 0.20 vs. 1.24 ± 0.14), but without significant differences. The highest BHB serum levels were obtained on days 12 and 19 of lactation in the CON group and in the CPL group on day 12. The cows in CPL group had lower BHB levels and FPR ratio, mostly, in the optimal range or below, while cows from CON group had FPR higher than optimal on days 19, 26 and 33 after parturition. In the CON and CPL groups 17.5% and 7.9% cows, respectively suffered from subclinical ketosis. On days 7, 12 and 19 non-esterified fatty acids were significantly higher in the CON group than in the CPL group. The cows from the CON group were in severe and longer negative energy balance than the cows from the CPL group. In conclusion, the CPL had positive effects on BHB serum levels and FPR during early lactation in Holstein-Friesian cows.

Evaluation of some blood liver parameters in cows with subclinical and clinical ketosis

The purpose of the present study was to establish the changes in some blood liver parameters in cows in different physiological conditions with subclinical (SCK) and clinical ketosis (CK). The study was performed on 157 Holstein cows with annual milk yield of 9,000–11,000 L. The animals were divided into 3 groups: I group – pregnant cows (from day 15 to day 0 pre-calving); II group – recently calved (from day 0 to day 15 postpartum) and III group – lactating (from day 30 to 45 postpartum). Blood concentrations of β-hydroxybutyric acid (ВНВА) (mmol/L), glucose (mmol/L), total protein (g/L), albumin (g/L) and total bilirubin (μmol/L) were assayed in all cows. The animals were divided in groups with SCK and CK according to their blood BHBA levels. It was established, that the con-centrations of total bilirubin were statistically significantly elevated vs control groups, while blood glucose, total protein and albumin values decreased, reflecting the impaired liver function in cows with SCK and CK.

Biomarkers from automatic milking system as an indicator of subclinical acidosis and subclinical ketosis in fresh dairy cows.

The objective of this study was to determine the association between subclinical acidosis (SARA) and subclinical ketosis (SCK) with biomarkers from an automatic milking system (AMS) measuring in relation to rumination time (RT), milk yield (MY), bodyweight (BW), milk temperature, the milk fat-to-protein ratio, and the electrical conductivity of milk at the udder quarters-level which can be read in fresh dairy cows. During the course of the study, all of the fresh dairy cows (n=711) were examined according to a general clinical investigation plan. The cows were selected for 1-30 days of milk (DIM) and were milked using Lely Astronaut® A3 milking robots with free traffic. Rumination time shows a statistically significant positive correlation with milk yield (milk temperature) and is negatively correlated with the fat and protein ratio. Healthy cows demonstrated the highest level of rumination time and the lowest milk temperature. The average BW for these cows was 1.64% lower than for the SARA group and the BW kg was 2.10% higher than SCK cows. MY was 14.01% lower in comparison with SARA and 6.42% higher in comparison with SCK. According to these results, some biomarkers from the AMS have an association with SARA and SCK. However, further research with a higher number of cows is needed to confirm this conclusion.

Evaluation of a handheld device for the measurement of beta-hydroxybutyrate in capillary blood obtained by the puncture of the vulva as well as in venous whole blood in cattle.

A negative energy balance is a common condition in high yielding dairy cows causing the production of ketone bodies (KB), including beta-hydroxybutyrate (BHB), defined as subclinical ketosis (SCK) if clinical signs are missing. The aim of the present study was to evaluate a handheld electronic device for the detection of SCK (BHB-concentration > 1.2 mmol/l), in capillary blood and venous whole blood in cows (WellionVet BELUA, MED TRUST Handels GmbH, Marz, Austria) as well as the feasibility of the puncture of the external vulva with a single use lancet. For this purpose, the blood BHB-concentration was tested in 250 venous and capillary blood samples and compared to the results of a certified laboratory. The majority (76.3%) of the animals displayed no signs of discomfort related to the puncture and in 74.2% the procedure was successful on the first attempt. The BHB-concentrations detected in capillary blood showed good agreement with the reference method, both in capillary (correlation coefficient 0.94 (p⟨0.001), Kappa-value 0.89) and venous whole blood (correlation coefficient of 0.95 (p⟨0.001), Kappa-value 0.89). Altogether, 98% of all the samples were correctly classified as SCK or non-SCK by the handheld device in capillary blood (sensitivity 0.96, specificity 0.98) and 97.4% in venous whole blood (sensitivity 0.889, specificity 0.991), respectively. An increase in the correlation by the adaptation of the cut off level could not be achieved for both sampling sites.

Prevention and Prediction of Displaced Abomasum in Dairy Cows

The objective of this article is to summarize studies that have been conducted on the prevention and prediction of displaced abomasum in dairy cows. Our findings indicate that displaced abomasum is a moderately heritable trait. Subclinical ketosis is a significant risk factor of displaced abomasum. Thus, displaced abomasum incidence might be lowered by genetic selection and by prevention of subclinical ketosis. To predict displaced abomasum, aspartate-aminotransferase activity in blood, B-hydroxybutyrate concentration in blood and milk, and the fat-protein-ratio in milk may be used. All of these parameters are frequently increased prior to the diagnosis of displaced abomasum.

Herd health monitoring in dairy farms – discover metabolic diseases. An overview

The transition period, 3 weeks before and 3 weeks after calving, is inevitably accompanied by a negative energy balance, which sometimes causes metabolic disturbances, such as ketosis. Subclinical ketosis (SCK) is defined as an increase in the β-hydroxybutyrate (BHB) concentration to ≥ 1.2 mmol/l in the blood. According to a recent study, a value of ≥ 0.7 mmol/l of non-esterified fatty acids (NEFA) in the blood indicates the potential development of the poor metabolic adaption syndrome (PMAS). With a herd prevalence of 21 %, and an incidence of approximately 40 % within the first 2 weeks after calving, SCK is a relevant herd health problem. The milk yield decreases in the first 2 weeks postpartum by 3-5.3 kg/d for each ketotic cow, and the total milk reduction through the whole lactation period of 305 days averages 112 kg (SD 89 kg). Although the cow does not display any clinical signs of ketosis at this stage, the risk of developing associated production diseases like retained placenta, metritis, displaced abomasum, lameness and clinical ketosis increases and the expected performance in terms of milk production will decrease. The herd health status deteriorates and the risk for early culling increases. Another impact factor is the financial aspect, which includes costs for early death, reduced milk production, reproduction losses, and associated production diseases. In the literature, the calculated costs per SCK case vary between $ 78 and $ 289. The gold standard diagnostic test for SCK is the photometric measurement of BHB in blood. This method is accurate, but results are delayed due to the required laboratory analysis. There are also some rapid cow-side tests, i. e. urine or milk strip tests available to identify ketotic cows. The common disadvantage of these methods is that they are not suitable for herd health monitoring because of the need to collect samples from each cow manually and the high rates of false negative results. However, Fourier transform infrared spectroscopy is suitable for herd health monitoring. It is already being used for the analysis of milk composition. This inexpensive, rapid and simple technique has a specificity of 83.8 % and a sensitivity of 82.4 %. Therefore, FTIR is an early and easy method for detecting ketotic cows, that could help reduce financial and performance losses associated with ketosis.

The role of altered immune function during the dry period in promoting the development of subclinical ketosis in early lactation

Subclinical ketosis (SCK) may impair white blood cell (WBC) function and thus contribute to the risk of disease postpartum. This preliminary study investigated changes occurring in the immune system before disease onset to elucidate their role in the occurrence of SCK. A group of 13 Holstein dairy cows were housed in tie-stalls and retrospectively divided into 2 groups based on their levels of β-hydroxybutyrate (BHB) measured in plasma between calving day and 35 d from calving (DFC). Levels of BHB <1.4 mmol/L were found in 7 cows (control cows, CTR group) and levels >1.4 mmol/L were found in 6 cows at ≥1 of 6 time points considered (cows with SCK, KET group). From -48 to 35 DFC, body condition score, body weight, dry matter intake, rumination time, and milk yield were measured, and blood samples were collected regularly to assess the hematochemical profile and test the WBC function by ex vivo challenge assays. Data were submitted for ANOVA testing using a mixed model for repeated measurements that included health status and time and their interactions as fixed effects. Compared with CTR cows, KET cows had more pronounced activation of the immune system (higher plasma concentrations of proinflammatory cytokines, myeloperoxidase, and oxidant species, and greater IFN-γ responses to Mycobacterium avium), higher blood concentrations of γ-glutamyl transferase, and lower plasma concentrations of minerals before calving. Higher levels of nonesterified fatty acids, BHB, and glucose were detected in KET cows than in CTR cows during the dry period. The effect observed during the dry period was associated with a reduced dry matter intake, reduced plasma glucose, and increased fat mobilization (further increases in nonesterified fatty acids and BHB) during early lactation. A reduced milk yield was also detected in KET cows compared with CTR. The KET cows had an accentuated acute-phase response after calving (with greater concentrations of positive acute-phase proteins and lower concentrations of retinol than CTR cows) and impaired liver function (higher blood concentrations of glutamate-oxaloacetate transaminase and bilirubin). The WBC of the KET cows, compared with CTR cows, had a reduced response to an ex vivo stimulation assay, with lower production of proinflammatory cytokines and greater production of lactate. These alterations in the WBC could have been driven by the combined actions of metabolites related to the mobilization of lipids and the occurrence of a transient unresponsive state against stimulation aimed at preventing excessive inflammation. The associations identified here in a small number of cows in one herd should be investigated in larger studies.

Effect of Saccharomyces cerevisiae fermentation product on feed intake parameters, lactation performance, and metabolism of transition dairy cattle

The transition period in dairy cattle is characterized by many stressors, including an abrupt diet change, but yeast product supplementation can alter the rumen environment to increase dairy cattle productivity. Saccharomyces cerevisiae fermentation product (SCFP) was fed from -29 ± 5 to 42 d relative to calving (RTC) to evaluate the effects on feed intake, milk production, and metabolism. Treatments were control (n = 30) or SCFP (n = 34) incorporated into a total mixed ration. Cows were individually fed 3×/d prepartum and 2×/d postpartum. Blood samples were collected once during each of the following time points RTC: d -28 to -24 (wk -4), d -14 to -10 (wk -2), d 3 to 7 (wk 1), d 12 to 16 (wk 2), and d 31 to 35 (wk 5). Liver biopsies were taken once between d -19 and d -12 (wk -3) and at 14 d in milk. Cows were milked 2×/d, and samples were taken 2 d/wk for composition analysis. Dry matter intake did not differ by treatment, but SCFP increased meals per day and decreased time between meals. Body weight (measured at enrollment, d 0, and d 42 RTC) and body condition score (scored weekly) were not affected by treatment. Milk, energy-corrected milk, and fat-corrected milk yields did not differ by treatment. Milk fat concentration was greater for SCFP, with significant differences in wk 4 and 5. Milk lactose concentration tended to be greater for the control and milk urea nitrogen tended to be lesser for the control, but there were no treatment effects on milk protein concentration or somatic cell count. Assuming equal digestibility, energy balance deficit was greater for SCFP than for the control (-6.15 vs. -4.34 ± 0.74 Mcal/d), with significant differences in wk 4 and 5. Plasma concentrations of free fatty acids, β-hydroxybutyrate, glucose, and insulin did not differ with treatment, but cholesterol was greater for SCFP. Liver triglyceride increased and liver cholesterol decreased with time. Liver triglyceride did not differ by treatment, but liver cholesterol tended to be lesser in SCFP. Relative mRNA abundance of cholesterol-related genes (SREBF2, HMGCS1, HMGCR, MTTP, SPOB100, APOA1), FGF21, and CPT1A did not differ by treatment, but PCK1 tended to be greater for SCFP. The ketogenic transcript HMGCS2 was greater for SCFP, which aligns with SCFP increasing incidence of subclinical ketosis; however, BDH did not differ between treatments. In conclusion, SCFP supplementation increased meals per day with less time between meals, increased milk fat concentration, altered cholesterol metabolism, and increased incidence of subclinical ketosis, but early-lactation milk yield and metabolism were generally unaffected.

Genome-wide association analysis for \u03b2-hydroxybutyrate concentration in Milk in Holstein dairy cattle

BackgroundKetosis in dairy cattle has been shown to cause a high morbidity in the farm and substantial financial losses to dairy farmers. Ketosis symptoms, however, are difficult to identify, therefore, the amount of ketone bodies (mainly β-hydroxybutyric acid, BHB) is used as an indicator of subclinical ketosis in cows. It has also been shown that milk BHB concentrations have a strong correlation with ketosis in dairy cattle. Mid-infrared spectroscopy (MIR) has recently became a fast, cheap and high-throughput method for analyzing milk components. The aim of this study was to perform a genome-wide association study (GWAS) on the MIR-predicted milk BHB to identify genomic regions, genes and pathways potentially affecting subclinical ketosis in North American Holstein dairy cattle.ResultsSeveral significant regions were identified associated with MIR-predicted milk BHB concentrations (indicator of subclinical ketosis) in the first lactation (SCK1) and second and later lactations (SCK2) in Holstein dairy cows. The strongest association was located on BTA6 for SCK1 and BTA14 on SCK2. Several SNPs on BTA6 were identified in regions and variants reported previously to be associated with susceptibility to ketosis and clinical mastitis in Jersey and Holstein dairy cattle, respectively. One highly significant SNP on BTA14 was found within the DGAT1 gene with known functions on fat metabolism and inflammatory response in dairy cattle. A region on BTA6 and three SNPs on BTA20 were found to overlap between SCK1 and SCK2. However, a novel region on BTA20 (55–63 Mb) for SCK2 was also identified, which was not reported in previous association studies. Enrichment analysis of the list of candidate genes within the identified regions for MIR-predicted milk BHB concentrations yielded molecular functions and biological processes that may be involved in the inflammatory response and lipid metabolism in dairy cattle.ConclusionsThe results of this study confirmed several SNPs and genes identified in previous studies as associated with ketosis susceptibility and immune response, and also found a novel region that can be used for further analysis to identify causal variations and key regulatory genes that affect clinical/ subclinical ketosis.

PREVALENCE OF SUB-CLINCIAL KETOSIS AND ITS ASSOCIATED COW LEVEL RISK FACTORS IN LACTATING DAIRY CROSS-BRED COWS IN BANGLADESH

Background: Ketosis is one of the most economically important metabolic diseases commonly found in high milk producing dairy cows worldwide. Objectives: The main objectives of this study were: (a) to evaluate the relationship between the urinary ketone bodies Rothera’s test and the serum glucose level to determine the prevalence of sub-clinical ketosis (SCK) and (b) to explore the cow-level risk factors associated with SCK in cross-bred dairy cows. Materials and Methods: Two types of cross-bred, Holstein Friesian  Local (HF  L) and Shahiwal  Local (SH  L) of a total of 68 lactating cows of three dairy herds were randomly selected to study the SCK from January to May 2012. Serum glucose level (SGL) was estimated by using Reflotron Glucose test strip (Roche) and urinary ketone bodies (UKB) by Rothera’s nitroprusside test. Results: An overall 25% prevalence of SCK was detected by Rothera’s test of which comparatively higher percentage of SCK was recorded in HF  L (25.9%) than SH  L (21.43%) cross-bred lactating cows. The overall SGL of Rothera’s test positive cases varied from 30 to 39 mg / dl with an average of 34.24  2.44 which was significantly (p &lt; 0.001) lower than the Rothera’s test negative cows (40 to 49 and 46.27  3.77 mg / dl). The SCK detected on Rothera’s test was compared with SGL which was 100% sensitivity at  39 mg / dl which could be considered as a ‘cutoff point’ of SGL for SCK. Results of the Rothera’s test were highly correlated with the concentrations of SGL. The significantly (p &lt; 0.01) highest prevalence of SCK was recorded in the fourth parity (66.7%) and fourth week of lactation (46.7%) in comparison to their respective parameters. Conclusions: The present findings reveal that the prevalence of SCK in lactating dairy cows in Bangladesh is very high and remain undetected and unattended. To prevent the SCK, feeding a good feed stuff and implementing good management at the transition period with regular testing for detecting SCK to reduce the consequences and economic losses caused by SCK in dairy industry in Bangladesh. Keywords: Serum glucose level, Rothera’s test, Subclinical ketosis, Cross-bred dairy cows, Cow-level risk factors

Prevalence of excessive negative energy balance in commercial United Kingdom dairy herds

The objectives of this study were to determine the individual animal and herd level prevalence of excessive negative energy balance (eNEB) in commercial UK dairy herds. Between April 2006 and March 2015, blood samples from 84,369 individual cows from 1748 different UK farms were received by a commercial laboratory service specializing in dairy cow nutritional monitoring. Following removal of all potential duplicate cows, the final dataset comprised 69,161 unique individual cows. The prevalence of eNEB was determined using plasma thresholds of β-hydroxybutyrate (BHB), non-esterified fatty acids (NEFA) and glucose.Overall prevalence of subclinical ketosis (SCK) in the first 20 days of lactation was 28.5%, 17.3% and 11.7% using BHB thresholds of 1.0, 1.2 and 1.4 mmol/L respectively. Prevalence of NEFA values ≥0.5 mmol/L in the last 10 days prior to calving was 26.0%, and 40.3% of cows had NEFA values ≥0.7 mmol/L in the first 20 days in milk (DIM). Combining BHB, NEFA and glucose showed that 52.0% of cows had one or more of the three biochemical measures of energy balance outside the respective threshold value in the last 10 days pre-calving, and 75.2% of cows showed a similar biochemical pattern in the first 20 DIM. The median herd prevalence of elevated BHB and/or NEFA was 37.5% in late pregnancy and 59.8% in the first 20 DIM, with substantial herd variation. Using multiple measures for the assessment of energy balance, this study has shown that eNEB affects substantial numbers of UK dairy cows.

The association between metabolic profile indices, clinical parameters, and ultrasound measurement of backfat thickness during the periparturient period of dairy cows

This study aimed to evaluate clinical and biochemical changes in dairy cows during periparturient period. It was carried out on 38 multiparous Holstein/Fersian crossbreed dairy cows 3–11 years old. Using ultrasonography for measurement backfat thickness (BFT) for detection of the energy deficit. BFT on dairy cattle is used to monitor changes in subcutaneous fat thickness which represent changes in energy stores. On the basis of clinical examination and assessment of BHBA concentration in blood, cows were classified to four groups, control healthy cows (C = 16), subclinical ketosis (SCK = 10), cows with retained placenta (RP = 6), and clinical mastitis (CM = 6). BFT showed a significant decrease (p < 0.05) after parturition in all diseased groups compared with healthy. The plasma level of NEFA and BHBA showed a significant increase (p < 0.05) at 2 weeks a.p (antepartum) and 2 weeks p.p (postpartum) in RP and SCK than other groups, respectively. The plasma level of glucose showed a significant decrease (p < 0.05) at 2 weeks p.p in SCK group. The plasma level of insulin showed a significant decrease (p < 0.05) at 4 weeks a.p in RP group and in all groups after parturition. It could be concluded that production diseases induced clinical, biochemical, and subcutaneous fat changes in dairy cows.

Incidence and risk factors for ketosis in grazing dairy cattle in the Cundi-Boyacencian Andean plateau, Colombia.

Ketosis is a metabolic disorder that has an important impact on health and productivity in dairy cattle during early lactation. In Colombia, the incidence and risk factors for ketosis development have not been studied. The objectives of the present study were to determine the incidence of subclinical (SCK) and clinical ketosis (CK) and to determine the risk factors associated with ketosis within the first 6weeks of lactation in dairy cattle in Colombia. A prospective cohort study was carried out. A convenience sample of 150 lactating dairy cows from ten commercial dairy farms in the Cundi-Boyacencian Andean plateau were tested weekly using a point of care device to measure β-hydroxybutyrate during the first 6weeks of lactation. Incidence of SCK and CK was calculated. Risk factors were evaluated using a survey for each animal and for each farm. Potential risk factors were evaluated using a X2 test, Relative Risk was calculated for significant variables by the X2 test (P ≤ 0.05) and these variables were included in the logistic regression model. Cumulative incidence of SCK was 25.33%, 3.33% for CK, and overall incidence of ketosis was 26%. In the logistic regression model, parity 3 or more, herd size > 150 animals, body condition score ≥ 3, retained placenta, and metritis were determined as risk factors for ketosis. The results of this study confirm previous reports in which a high body condition score, increased parity, herd size, retained placenta, and metritis are associated with an increased risk of ketosis in stabled and grazing cattle.

Метаболический стресс у сухостойных коров и нетелей при развитии субклинического кетоза

Метаболический стресс у сухостойных коров и нетелей при развитии субклинического кетоза