First Broad-Range Serological Survey of Crimean-Congo Hemorrhagic Fever among Hungarian Livestock.

(1) Background: Crimean-Congo hemorrhagic fever (CCHF) is an emerging tick-borne disease endemic in Africa, Asia, the Middle East, and the Balkan and Mediterranean regions of Europe. Although no human CCHF cases have been reported, based on vector presence, serological evidence among small vertebrates, and the general human population, Hungary lies within high evidence consensus for potential CCHF introduction and future human infection. Thus, the aim of our pilot serosurvey was to assess CCHF seropositivity among cattle and sheep as indicator animals for virus circulation in the country. (2) Methods: In total, 1905 serum samples taken from free-range cattle and sheep in 2017 were tested for the presence of anti-CCHF virus IgG antibodies using commercial ELISA and commercial and in-house immunofluorescent assays. (3) Results: We found a total of eleven reactive samples (0.58%) from five administrative districts of Hungary comprising 8 cattle and 3 sheep. The most affected regions were the south-central and northwestern parts of the country. (4) Conclusions: Based on these results, more extended surveillance is advised, especially in the affected areas, and there should be greater awareness among clinicians and other high-risk populations of the emerging threat of CCHF in Hungary and Central Europe.

Oestrogen and progesterone concentrations in intrapartum cows with insufficient cervix dilation.

The cervix is an important organ that has to dilate sufficiently at delivery to allow the foetus to transition to extrauterine life. Insufficient dilatation of the cervix (IDC) is a frequent cause of dystocia in cattle. The mechanisms underlying cervical opening and the pathogenesis of IDC are still widely unclear. Systematic studies on the relationship between IDC and steroid hormones have been limited and have yielded inconsistent findings. This study aimed to measure oestrogen and progesterone (P4) concentrations in intrapartum cows presented with dystocia due to IDC and in a comparison (C) group of cows with eutocic delivery. Before any obstetrical procedures, and right after the initial evaluation, blood samples were taken from IDC and C animals. Concentrations of P4, oestradiol-17ß (E2), free total oestrogens (FTE) and conjugated total oestrogens (CTE) were measured by established radioimmunoassays. Concentrations of P4 (p = .538), FTE (p = .065) and CTE (p = .605) were not statistically different between C and IDC groups. However, E2 levels in group C were significantly lower when compared to those in the IDC group (p = .013), which is inconsistent with the function of oestrogens in cervical dilatation. The correlation analysis demonstrated significant positive correlations between the pairs P4 versus FTE, P4 versus E2 and FTE versus E2 in group C and between the pair FTE versus E2 in group IDC. In conclusion, the results suggest that local activities of steroids relevant to the aetiology of IDC are not reflected by concentrations in the systemic circulation or that other factors are clearly more important.

A novel diagnostic approach to Paratuberculosis in dairy cattle using near-infrared spectroscopy and aquaphotomics.

Introduction: As a contagious and chronic disease in the livestock industry, Paratuberculosis is a significant threat to dairy herds' genetic and economic resources. Due to intensive breeding and high production of dairy cattle, the incidence and prevalence are higher. Developing non-destructive diagnostic methods for the early detection and identification of healthy animals is paramount for breeding programs. Conventional methods are almost entirely destructive, have low accuracy, lack precision, and are time-consuming. Near-infrared spectroscopy (NIRS) and aquaphotomics can detect changes in biofluids and thus have the potential to diagnose disease. This study aimed to investigate the diagnostic ability of NIRS and aquaphotomics for Paratuberculosis in dairy cattle. Methods: Blood plasma from dairy cattle was collected in the NIR range (1,300 nm to 1,600 nm) 60 days before and 100 days to 200 days after calving in two groups, positive and negative, using the same consecutive enzyme-linked immunosorbent assay test results three times as a reference test. Results: NIRS and aquaphotomics methods invite 100% accuracy, sensitivity, and specificity to detect Paratuberculosis using data mining by unsupervised method, Principal Component Analysis, and supervised methods: Soft Independent Modeling of Class Analogiest, Linear Discriminant Analysis, Quadratic Discriminant Analysis, Partial Least Square-Discriminant Analysis, and Support Vector Machine models. Discussion: The current study found that monitoring blood plasma with NIR spectra provides an opportunity to analyze antibody levels indirectly via changes in water spectral patterns caused by complex physiological changes, such as the amount of antibodies related to Paratuberculosis by aquagram.

Performance of an automated immunoturbidimetric assay for bovine serum amyloid A.

BACKGROUND: Acute phase proteins are a group of vital constituents of the innate immune system, which may also serve as circulatory biomarkers of inflammation. The major acute phase protein serum amyloid A (SAA) is a reliable and sensitive biomarker in cows, allowing for rapid detection of inflammatory disease. A multispecies automated immunoturbidimetric assay (VET-SAA, Eiken) has been validated for horses, dogs, and cats, and it has been used to measure SAA concentrations in bovine samples. OBJECTIVES: The aim of the present study was to perform an analytical validation of the VET-SAA immunoturbidometric assay based on monoclonal antihuman SAA antibodies for the measurement of SAA in clinical samples from cows. METHODS AND RESULTS: The validation included an assessment of imprecision, inaccuracy, and detection limit, as well as an evaluation of the overlap performance, using banked serum from healthy and sick cows with or without inflammatory disease. Intra- and interassay variation ranged from 0.91% to 2.9% and 2.5% to 5.8%, respectively. The assay was performed with acceptable accuracy within a clinically relevant range of SAA, although minor signs of inaccuracy were detected. Overlap performance was acceptable, with the VET-SAA assay able to differentiate between healthy cows and cows with inflammatory and noninflammatory conditions. The automated VET-SAA assay is considered acceptable for the measurement of SAA in cows.

Chloride and lactate as prognostic indicators of calf diarrhea from eighty-nine cases.

IMPORTANCE: Deaths due to neonatal calf diarrhea are still one of the most critical problems of cattle breeding worldwide. Determining the parameters that can predict diarrhea-related deaths in calves is especially important in terms of prognosis and treatment strategies for the disease. OBJECTIVE: The primary purpose of this study was to determine mortality rates and durations, survival status, and predictive prognosis parameters based on vital signs, hematology, and blood gas analyses in neonatal diarrheic calves. METHODS: The hospital automation system retrospectively obtained data from 89 neonatal diarrheic calves. RESULTS: It was found that 42.7% (38/89) of the calves brought with the complaint of diarrhea died during hospitalization or after discharge. Short-term and long-term fatalities were a median of 9.25 hours and a median of 51.50 hours, respectively. When the data obtained from this study is evaluated, body temperature (°C), pH, base excess (mmol/L), and sodium bicarbonate (mmol/L) parameters were found to be lower, and hemoglobin (g/dL), hematocrit (%), lactate (mmol/L), chloride (mmol/L), sodium (mmol/L) and anion gap (mmol/L) parameters were found to be higher in dead calves compared to survivors. Accordingly, hypothermia, metabolic acidosis, and dehydration findings were seen as clinical conditions that should be considered. Logistic regression analysis showed that lactate (odds ratio, 1.429) and CI- (odds ratio, 1.232) concentration were significant risk factors associated with death in calves with diarrhea. CONCLUSIONS AND RELEVANCE: According to the findings obtained from this study, the determination of lactate and Cl- levels can be used as an adjunctive supplementary test in distinguishing calves with diarrhea with a good prognosis.

Trypanosoma vivax in and outside cattle blood: Parasitological, molecular, and serological detection, reservoir tissues, histopathological lesions, and vertical transmission evaluation.

This study reports assessment of the sensitivity of diagnostic techniques to detect T. vivax in experimentally infected cattle. Additionally, it describes T. vivax extravascular parasitism during the acute and chronic phases of trypanosomosis and congenital transmission. The T. vivax diagnosis was compared using blood samples collected from the jugular, coccygeal and ear tip veins. For this study, 13 males and two females were infected with ≈ 1 × 106 viable T. vivax trypomastigotes (D0). One animal was kept as a negative control during the entire study. The 13 infected males were euthanized between 14 and 749 days post-infection (DPI). After confirming the cyclicity of both females (9 months of age), they were naturally mated with a bull. One female was euthanized at 840 DPI, and the other at 924 DPI. The two calves, one from each female, were euthanized at six months of age (924 DPI), and the negative control at 924 DPI. During this period, T. vivax in blood was assessed using direct methods (Woo test, cPCR, microscopic examination of fresh wet blood films and parasite quantification - Brener method), and serological methods (IFAT, ELISA, and IA). Tissue samples were collected from the liver, spleen, brain, cerebellum, heart, testicles, epididymis, kidneys, eyeballs, pre-scapular lymph nodes, ear tips, mammary glands, uterus, and ovaries. The protozoan DNA was examined using LAMP. There was no difference in the detection of T. vivax using the Woo test and Brener method among the jugular, coccygeal, and ear tip veins. The sensitivity of the detection methods varied depending on the disease phase. Direct methods (Woo test, Brener method, and cPCR) demonstrated higher sensitivity during the acute phase, while serological methods (IFAT, ELISA, and IA) were more sensitive during the chronic phase. Anti-T. vivax antibodies were detected up to 924 DPI. Tissue evaluation using LAMP demonstrated the presence of T. vivax DNA and associated histopathological changes up to 840 or 924 DPI. Only in mammary glands and ovaries was no DNA detected. The most frequently observed histopathological alteration was lymphohistioplasmocytic inflammatory infiltrate. No transplacental transmission of T. vivax was observed.

Comparison of serum concentrations of pregnancy-associated glycoproteins and estrone sulphate during pregnancy in eutocia and dystocia beef cattle.

Preventing dystocia can stabilise beef cattle management. This study aimed to investigate the relationship between serum pregnancy-associated glycoproteins (PAGs) S-N values and estrone sulphate (E1S) concentrations during pregnancy and the calf birth weight in beef cattle and to evaluate their usefulness as new predictive parameters for dystocia due to foetal overgrowth. Thirty-eight pregnant Japanese Black cattle were used. Blood samples were collected at 40, 70, 100, 150, 200, 250, 280, and 285 days after artificial insemination (AI), and birth weight of the offspring was measured. Serum PAGs S-N values and E1S concentrations were measured, and the area under the curve (AUC) and the ratio of change based on 70 days after AI were calculated, followed by calculation of the correlation coefficient with the birth weight of the offspring and comparison between the eutocia (n = 32) and dystocia (n = 6) groups. The birth weight of the offspring was moderately positively correlated with the AUC of serum PAGs S-N values and E1S concentrations in the second (r = 0.425, P < 0.01) and third (r = 0.595, P < 0.01) trimesters, respectively. The ratio of change in serum E1S concentrations between 70 and 280 days after AI was greater (P < 0.05) in the dystocia group (1276.6 ±â€¯229.1 %) than in the eutocia group (852.6 ±â€¯69.6 %). These results suggest that blood PAGs S-N values at mid-pregnancy (100-199 days after AI) and the ratio of changes in blood E1S concentrations between 70 and 280 days after AI may be new parameters for predicting dystocia.

Accuracy of early pregnancy diagnosis and determining pregnancy loss using different biomarkers and machine learning applications in dairy cattle.

This study aimed to compare the accuracy of IFN-τ stimulated gene abundance (ISGs) in peripheral blood mononuclear cells (PBMCs), CL blood perfusion by Doppler ultrasound (Doppler-US), plasma concentration of P4 on Day 21 and pregnancy-associated glycoproteins (PAGs) test on Day 25 after timed-artificial insemination (TAI) for early pregnancy diagnosis in dairy cows and heifers. Holstein cows (n = 140) and heifers (n = 32) were subjected to a hormonal synchronization protocol and TAI on Day 0. On Day 21 post-TAI, blood samples were collected for PBMC isolation and plasma concentration of P4. The CL blood perfusion was evaluated by Doppler-US. Plasma samples collected on Day 25 were assayed for PAGs. The abundance of ISGs (ISG15 and RSAD2) in PBMCs was determined by RT-qPCR. Pregnancy was confirmed on Days 32 and 60 post-TAI by B-mode ultrasonography. Statistical analyses were performed by ANOVA using the MIXED procedure and GLIMMIX in SAS software. The pregnancy biomarkers were used to categorize the females as having undergone late luteolysis (LL); early embryonic mortality (EEM); late embryonic mortality (LEM); or late pregnancy loss (LPL). The abundance of ISGs, CL blood perfusion by Doppler-US, and concentrations of P4 on Day 21, and PAGs test on Day 25 were significant (P < 0.05) predictors of early pregnancy in dairy cows and heifers. Dairy cows had a greater (P = 0.01) occurrence of LL than heifers, but there was no difference (P > 0.1) for EEM, LEM, and LPL in heifers compared to cows. Cows with postpartum reproductive issues had a greater (P = 0.008) rate of LEM and a lesser (P = 0.01) rate of LPL compared to cows without reproductive issues. In summary, the CL blood perfusion by Doppler-US had the highest accuracy and the least number of false negatives, suggesting it is the best predictor of pregnancy on Day 21 post-TAI. The PAGs test was the most reliable indicator of pregnancy status on Day 25 post-TAI in dairy heifers and cows. The application of machine learning, specifically the MARS algorithm, shows promise in enhancing the accuracy of predicting early pregnancies in cows.

Age-specific analysis of anti-müllerian hormone and liver biochemical parameters in freemartin holstein calves and heifers: A pilot study.

Freemartinism is the most common congenital anomaly among sexual disorders in dairy cows. This syndrome typically occurs in different-sex twin pregnancies and causes vascular anastomoses to form with the placenta in the early stages of fetal development. The study aims to determine the effectiveness of Anti-müllerian hormone (AMH) levels in calves and heifers of different age groups for diagnostic factors and to investigate the potential consequences of different hormone levels in different age groups on some liver biochemical parameters. The study involved 50 cattle from diverse age categories, divided into the freemartin group (FM Group, n=25) and the control group (C Group, n=25). Both FM and control groups were further divided into early-age (3-5 months), middle-aged (5-9 months), and older-aged groups (9-12 months). Serum AMH levels, along with total protein, albumin, and total cholesterol levels, were measured. While no statistically significant difference in AMH levels was observed in the early-age group (P:0.53), significant differences were determined in the middle (P:0.015) and older-age groups (P:0.01), where the FM group exhibited significantly decreased AMH levels compared to the control group. The evaluation of liver biochemistry revealed a statistically significant difference in total protein levels between the FM and control groups in the older age group (P:0.033). Consequently, it is reasonable to suggest that AMH levels may serve as a valid parameter for diagnosing freemartin syndrome in calves aged older than five months. Conversely, particularly in young calves, no significant differences in liver functionality were observed between freemartin-affected and healthy calves.

Foot-and-mouth disease-associated myocarditis is age dependent in suckling calves.

Myocarditis is considered a fatal form of foot-and-mouth disease (FMD) in suckling calves. In the present study, a total of 17 calves under 4 months of age and suspected clinically for FMD were examined for clinical lesions, respiratory rate, heart rate, and heart rhythm. Lesion samples, saliva, nasal swabs, and whole blood were collected from suspected calves and subjected to Sandwich ELISA and reverse transcription multiplex polymerase chain reaction (RT-mPCR) for detection and serotyping of FMD virus (FMDV). The samples were found to be positive for FMDV serotype "O". Myocarditis was suspected in 6 calves based on tachypnoea, tachycardia, and gallop rhythm. Serum aspartate aminotransferase (AST), creatinine kinase myocardial band (CK-MB) and lactate dehydrogenase (LDH), and cardiac troponins (cTnI) were measured. Mean serum AST, cTn-I and LDH were significantly higher (P < 0.001) in < 2 months old FMD-infected calves showing clinical signs suggestive of myocarditis (264.833 ± 4.16; 11.650 ± 0.34 and 1213.33 ± 29.06) than those without myocarditis (< 2 months old: 110.00 ± 0.00, 0.06 ± 0.00, 1050.00 ± 0.00; > 2 months < 4 months: 83.00 ± 3.00, 0.05 ± 0.02, 1159.00 ± 27.63) and healthy control groups (< 2 months old: 67.50 ± 3.10, 0.047 ± 0.01, 1120.00 ± 31.62; > 2 months < 4 months: 72.83 ± 2.09, 0.47 ± 0.00, 1160.00 ± 18.44). However, mean serum CK-MB did not differ significantly amongst the groups. Four calves under 2 months old died and a necropsy revealed the presence of a pathognomic gross lesion of the myocardial form of FMD known as "tigroid heart". Histopathology confirmed myocarditis. This study also reports the relevance of clinical and histopathological findings and biochemical markers in diagnosing FMD-related myocarditis in suckling calves.

Towards sustainable and humane dairy farming: A low-cost electrochemical sensor for on-site diagnosis of milk fever.

Milk fever is a metabolic disorder that predominantly affects dairy animals during the periparturient period and within four weeks of calving. Milk fever is primarily attributed to a decrease in the animal's serum Ca2+ levels. Clinical milk fever occurs when Ca2+ concentration drops below 1.5 mM (6 mg/dL). Without prompt intervention, clinical milk fever leads to noticeable physical symptoms and health complications including coma and fatality. Subclinical milk fever is characterized by Ca2+ levels between 1.5 and 2.12 mM (6-8.48 mg/dL). Approximately 50% of multiparous dairy cows suffer from subclinical milk fever during the transition to lactation. The economic impact of milk fever, both direct and indirect, is substantial, posing challenges for farmers. To address this issue, we developed a low-cost electrochemical sensor that can measure bovine serum calcium levels on-site, providing an opportunity for early detection of subclinical and clinical milk fever and early intervention. This calcium sensor is a scalable solid contact ion sensing platform that incorporates a polymeric calcium-selective membrane and ionic liquid-based reference membrane into laser-induced graphene (LIG) electrodes. Our sensing platform demonstrates a sensitivity close to the theoretical Nernstian value (29.6 mV/dec) with a limit of detection of 15.6 µM and selectivity against the species in bovine serum. Moreover, our sensor can detect Ca2+ in bovine serum with 91% recovery.

Comparison of behavioral and physiological changes in postpartum healthy and inflammatory diseased cows.

During parturition, cows often experience intense pain and stress, which increases the risk of inflammatory diseases. This study aimed to compare the postpartum health status between healthy cows and those diagnoses with inflammatory diseases by examining behavioral and heart rate (HR) variability (HRV) changes, to provide information before the onset of disease. Eight Holstein cows were used in this study. HR, parameters of HRV (low-frequency power: LF; high-frequency power: HF; LF/HF ratio, and total power) and time budget of individual maintenance behaviors (standing, recumbency, feeding, rumination while standing and lying, and sleep) were continuously recorded from 0 to 168 h postpartum. Milk and blood samples were collected daily. Cows were categorized as diseases based on the positive result of California mastitis test and/or serum haptoglobin concentration that exceeded 50 µg/ml after all blood samples have been collected. Compared to healthy individuals (n = 3), diseased cows (n = 5) exhibited higher HR, LF/HF, and lower total power (p < 0.05), suggesting the dominance of the sympathetic nervous system in cows with inflammatory diseases. Additionally, diseased cows showed an increased standing time budget and reduced recumbency (p < 0.05), which may be a behavioral strategy in response to discomfort from inflammation.

Serum metabolic profiling in pregnant Holstein cows 3 weeks prior to parturition using two-dimensional gas chromatography time-of-flight mass spectrometry.

This preliminary study explored potential serum biomarkers for predicting the onset of milk fever (MF), a bovine parturient disease with hypocalcemia. We conducted two-dimensional gas chromatography mass spectrometry-based metabolomics in 8 and 17 pregnant Holstein cows that did and did not develop MF 3 weeks later, respectively. In principal component analysis (PCA) applied to a dataset containing 1,498 metabolites, serum metabolites exhibited highly similar chemical profiles between cows with and without MF. PCA with a limited dataset of metabolites containing fatty acids, which had significantly different values between the groups and/or correlation coefficients of >0.5 for the serum calcium concentration, distinguished the two groups. These suggest the possibility of developing serum biomarkers for predicting bovine MF.

Genetic Background of Blood ß-Hydroxybutyrate Acid Concentrations in Early-Lactating Holstein Dairy Cows Based on Genome-Wide Association Analyses.

Ketosis is a common metabolic disorder in the early lactation of dairy cows. It is typically diagnosed by measuring the concentration of ß-hydroxybutyrate (BHB) in the blood. This study aimed to estimate the genetic parameters of blood BHB and conducted a genome-wide association study (GWAS) based on the estimated breeding value. Phenotypic data were collected from December 2019 to August 2023, comprising blood BHB concentrations in 45,617 Holstein cows during the three weeks post-calving across seven dairy farms. Genotypic data were obtained using the Neogen Geneseek Genomic Profiler (GGP) Bovine 100 K SNP Chip and GGP Bovine SNP50 v3 (Illumina Inc., San Diego, CA, USA) for genotyping. The estimated heritability and repeatability values for blood BHB levels were 0.167 and 0.175, respectively. The GWAS result detected a total of ten genome-wide significant associations with blood BHB. Significant SNPs were distributed in Bos taurus autosomes (BTA) 2, 6, 9, 11, 13, and 23, with 48 annotated candidate genes. These potential genes included those associated with insulin regulation, such as INSIG2, and those linked to fatty acid metabolism, such as HADHB, HADHA, and PANK2. Enrichment analysis of the candidate genes for blood BHB revealed the molecular functions and biological processes involved in fatty acid and lipid metabolism in dairy cattle. The identification of novel genomic regions in this study contributes to the characterization of key genes and pathways that elucidate susceptibility to ketosis in dairy cattle.

Relationship between hypocalcemia immediately after calving with metabolic disorders and body condition score in Holstein cows.

Background: Hypocalcemia is one of the most common transition period disorders that affects dairy cows and has been divided into clinical and subclinical types. Aim: This study aimed to investigate the relationship between postpartum serum calcium (Ca) concentrations with metabolic disorders and body condition score (BCS) in Holstein dairy cows. Methods: Two hundred and seventy-one Holstein cows were blocked from two commercial dairy herds based on parity (primiparous and multiparous) and serum Ca concentrations on calving day, 1 and 2 days postpartum were allocated to 1 of 3 groups: 1) Serum Ca concentration >8.5 mg/dl at the calving day, 1 and 2 days postpartum (normocalcemic); 2) serum Ca concentration ≤8.5 mg/dl on the calving day and 1 or 2 day postpartum (transient subclinical hypocalcemia (TSCH)); and 3) serum Ca concentration ≤8.5 mg/dl on the calving day, 1 and 2 days postpartum (persistent subclinical hypocalcemia (PSCH)). Results: The results showed that the primiparous and multiparous cows had the highest TSCH and PSCH percentages, respectively. Ca status after calving did not affect the BCS changes, incidence of milk fever, hypomagnesemia and hyperketonemia, and clinical and subclinical endometritis. The incidence of retained placenta, metritis, and subclinical mastitis was affected by Ca status after calving, so PSCH cows experienced 6.28, 6.43, and 5.9 times more retained placenta, metritis, and subclinical mastitis than normocalcemic cows, respectively. The culling rate within the first 60 days in milk for PSCH cows was 4.61 times more than for normocalcemic cows. Conclusion: Overall, the results of the study showed that cows with PSCH had a higher incidence of retained placenta; uterine infections, subclinical mastitis, and culling rate, but cows with TSCH were similar to healthy cows in terms of metabolic disorders and culling rate.

Genomic prediction of blood biomarkers of metabolic disorders in Holstein cattle using parametric and nonparametric models.

BACKGROUND: Metabolic disturbances adversely impact productive and reproductive performance of dairy cattle due to changes in endocrine status and immune function, which increase the risk of disease. This may occur in the post-partum phase, but also throughout lactation, with sub-clinical symptoms. Recently, increased attention has been directed towards improved health and resilience in dairy cattle, and genomic selection (GS) could be a helpful tool for selecting animals that are more resilient to metabolic disturbances throughout lactation. Hence, we evaluated the genomic prediction of serum biomarkers levels for metabolic distress in 1353 Holsteins genotyped with the 100K single nucleotide polymorphism (SNP) chip assay. The GS was evaluated using parametric models best linear unbiased prediction (GBLUP), Bayesian B (BayesB), elastic net (ENET), and nonparametric models, gradient boosting machine (GBM) and stacking ensemble (Stack), which combines ENET and GBM approaches. RESULTS: The results show that the Stack approach outperformed other methods with a relative difference (RD), calculated as an increment in prediction accuracy, of approximately 18.0% compared to GBLUP, 12.6% compared to BayesB, 8.7% compared to ENET, and 4.4% compared to GBM. The highest RD in prediction accuracy between other models with respect to GBLUP was observed for haptoglobin (hapto) from 17.7% for BayesB to 41.2% for Stack; for Zn from 9.8% (BayesB) to 29.3% (Stack); for ceruloplasmin (CuCp) from 9.3% (BayesB) to 27.9% (Stack); for ferric reducing antioxidant power (FRAP) from 8.0% (BayesB) to 40.0% (Stack); and for total protein (PROTt) from 5.7% (BayesB) to 22.9% (Stack). Using a subset of top SNPs (1.5k) selected from the GBM approach improved the accuracy for GBLUP from 1.8 to 76.5%. However, for the other models reductions in prediction accuracy of 4.8% for ENET (average of 10 traits), 5.9% for GBM (average of 21 traits), and 6.6% for Stack (average of 16 traits) were observed. CONCLUSIONS: Our results indicate that the Stack approach was more accurate in predicting metabolic disturbances than GBLUP, BayesB, ENET, and GBM and seemed to be competitive for predicting complex phenotypes with various degrees of mode of inheritance, i.e. additive and non-additive effects. Selecting markers based on GBM improved accuracy of GBLUP.

Detection of haptoglobin and serum amyloid A as biomarkers in naturally infected Mycoplasma bovis calves.

The livestock sector of Pakistan is increasing rapidly and it plays important role both for rural community and national economy. It is estimated that almost 8 million rural people are involved in livestock rearing and earning about 35-40 % of their income from the livestock sector. Mycoplasma bovis (M. bovis) infection causes significant economic losses in dairy animals especially young calf in the form of clinical illnesses such as pneumonia, poly-arthritis, respiratory distress and mortality. M. bovis is hard to diagnose and control because of uneven disease appearance and it is usually noticed in asymptomatic animals. For the identification of M. bovis in sub-clinical and clinical samples, determination of acute phase proteins i.e., haptoglobin (Hp) and serum amyloid A (SAA) are important tools for the timely diagnosis of disease. Therefore, early diagnosis of disease and hemato-biochemical changes are considered beneficial tools to control the infectious agent to uplift the economy of the dairy farmers. For this purpose, blood samples were collected from 200 calves of Bovidae family. Serum was separated from blood samples to determine the concentration of Hp and SAA, while blood samples were processed to determine hematological changes in blood from calves by using hematological analyzer. The blood plasma obtained from the blood samples was processed to measure oxidative stress factors. Lungs tissues from slaughterhouses/ morbid calves were collected to observe histopathological changes. The results of present study indicated that level of SAA and Hp remarkably increased (P < 0.05) in M. bovis infected calves in comparison to healthy calves. The oxidative stress markers indicated that nitric oxide and MDA levels in the infected calves increased significantly (P < 0.05), while infected claves had considerably lower levels of superoxide dismutase, catalase and glutathione. These findings indicate that oxidative stress play role to increase the level of APPs, while monitoring of APPs levels may serve as a valuable addition to the clinical evaluation of naturally infected calves with M. bovis. The hematological parameters were decreased significantly (P < 0.05). Altogether, this study suggests that Hp and SAA are proposed as promising biomarkers for detecting naturally occurring M. bovis infection in calves.

Analysis of blood biochemistry and non-targeted metabolomics of endometritis in dairy cows.

The incidence of bovine endometritis, which has a negative impact on the reproduction of dairy cows, has been recently increasing. In this study, the differential markers and metabolites of healthy cows and cows with endometritis were analyzed by measuring blood biochemical indicators and immune factors using biochemical and enzyme-linked immunosorbent assay kits combined with nontargeted metabolomics. The LC-QTOF platform was used to evaluate the serum metabolomics of healthy cows and cows with endometritis after 21-27 days of calving. The results showed that glucose, free fatty acid, calcium, sodium, albumin, and alanine aminotransferase levels were significantly lower in the serum of cows with endometritis than in healthy cows (P < 0.05). However, the serum potassium, interleukin-1, interleukin-6, and tumor necrosis factor levels were significantly higher in cows with endometritis (P < 0.05). In addition, the serum metabolome data analysis of the two groups showed that the expression of 468 metabolites was significantly different (P < 0.05), of which 291 were upregulated and 177 were downregulated. These metabolites were involved in 78 metabolic pathways, including amino acid, nucleotide, carbohydrate, lipid, and vitamin metabolism pathways; signal transduction pathways, and other biological pathways. Taken together, negative energy balance and immune activation, which are related to local abnormalities in amino acid, lipid, and carbohydrate metabolism, were the important causes of endometritis in dairy cows. Metabolites such as glucose, carnosine, dehydroascorbic acid, L-malic acid, tetrahydrofolic acid, and UDP-glucose may be used as key indicators in the hematological diagnosis and treatment of endometritis in dairy cows.

Blood parameters and parasite burden in cattle with chronic fascioliasis.

Fascioliasis is a trematodiasis that affects domestic and wild animals as well as humans worldwide. It is a well-recognized disease in livestock, were it produces serious economic losses. Yet in cattle, there is limited information about the burden of liver flukes and its relation to the eggs per gram shed to the environment. There is also lack of knowledge on the effect of parasite load in blood parameters of infected animals, which is important to evaluate the severity and progression of the disease. The objective of this work was to gain insight in these aspects. Cattle from Mendoza province, Argentina, were inspected at a farm and at the abattoir determining the presence or absence of Fasciola hepatica. Each animal was sampled for blood and feces and in the slaughterhouse the livers were inspected. Hematology and blood chemistry parameters were determined, feces were examined for F. hepatica eggs by a quantitative sedimentation technique and livers were thoroughly inspected to determine the number of flukes. Infected cattle presented a mild burden of liver flukes per animal, strongly correlated (r = 0.72) to the number of eggs per gram of feces. The total number of eggs (X̄=35,100) shed per animal to the environment and the type of livestock management techniques in the region exacerbate the role of cattle as efficient reservoirs of this disease. Statistically significant lower red blood cell, lymphocyte and neutrophil counts were observed in infected compared to uninfected animals. All hepatic parameters tested showed highly statistically significant differences (p < 0.001) as well as proteins by cause of rise of globulins in infected cattle. The correlation between the amount of flukes in the liver and the number of eggs per gram of faces indicates coprology as a reliable and cost-effective method to infer parasite burden. The impact of fascioliasis on blood parameters can be of aid for the veterinary practitioner on the assessment of this disease on cattle.

Blood gases, acid-base, and metabolic alterations in calves with bronchopneumonia diagnosed via clinical signs and thoracic ultrasonography: A cross-sectional study.

BACKGROUND: Bronchopneumonia (BP) in calves potentially causes systemic changes. OBJECTIVES: To describe metabolic, arterial blood gas, and acid-base disorders in calves with BP diagnosed by thoracic ultrasound (TUS), Wisconsin score (WISC), and combinations of WISC and TUS. ANIMALS: Two hundred thirty-one dairy preweaned dairy calves from 13 dairy farms. METHODS: Cross-sectional study. Each calf sequentially underwent arterial blood gas evaluation, WISC score, venous sampling, and TUS. Calves were grouped based on a single diagnostic method and combination of WISC and 2 TUS cutoffs (≥1 cm; ≥3 cm) as healthy, upper respiratory tract infection, subclinical BP, and clinical BP. RESULTS: Oxygenation and acid-base variables were unaffected. Glucose concentration in TUS-affected calves was significantly lower (P < .001) than in healthy calves (median ≥TUS1cm = 5.2 mmol/L 25%-75% interquartile range [IQR] 4.5-6.1,