Subclinical Mastitis In Cows Research Articles

Transcriptome analysis identifies the NR4A subfamily involved in the alleviating effect of folic acid on mastitis induced by high concentration of Staphylococcus aureus lipoteichoic acid

BackgroundStaphylococcus aureus (S. aureus) mastitis results in economic losses during dairy production. Understanding the biological progression of bovine S. aureus mastitis is vital for its prevention. Lipoteichoic acid is a key virulence factor of S. aureus (aLTA), but the main biological pathways involved in its effect on bovine mammary epithetionallial cells (Mac-T) apoptosis and necrosis have not been fully explored. Folic acid (FA) has anti-inflammatory and anti-apoptotic effects. However, the role of FA in mediating the effects of aLTA on apoptosis and necrosis remains unknown.ResultsWe found that low concentration of aLTA inhibited apoptosis and necrosis and that high concentration promoted the apoptosis and necrosis of Mac-T. FA pretreatment alleviated high concentration of aLTA induced apoptosis. Through transcriptomic analysis, we found that nuclear receptor subfamily 4 group A (NR4A), which alters the expression of downstream genes involved in apoptosis, proliferation, and inflammation, decreased under stimulation with a low concentration of aLTA and increased under stimulation with a high concentration of aLTA. Under stimulation with a high concentration of aLTA, the expression of the NR4A subfamily could be inhibited by FA. The results showed that aLTA may affect apoptosis and necrosis through the NR4A subfamily by targeting genes involved in bacterial invasion of epithelial cells, the IL-17 signaling pathway, DNA replication, longevity regulation, the cell cycle, and tight junction pathways. We further found that the expression trends of NR4A1 and the target genes of the NR4A subfamily (PTGS2, ESPL1, MCM5, and BUB1B) in the blood of healthy cows (Healthy), subclinical mastitis cows (SCM), and SCM supplemented with FA (SCM_FA) were consistent with those observed at the cellular level in this study.ConclusionsOur study revealed that low and high concentrations of aLTA have opposite effects on apoptosis and necrosis of Mac-T and that FA can alleviate the apoptosis induced by high concentration of aLTA. Transcriptome analysis revealed that the NR4A subfamily play a role in the ability of FA to alleviate the apoptosis and necrosis induced by high concentration of aLTA.

Proposal for the design of studies of intramammary antimicrobials to be conducted in Brazil for registration with the Ministry of Agriculture and Livestock

Before being made available to the Brazilian market, all veterinary medicines must be registered with the Ministry of Agriculture and Livestock after their efficacy, safety, and quality have been proven through clinical studies and scientific literature. Depending on the product class, the studies required by the regulatory authority must be carried out per Brazilian regulations and international reference guides. Some international organizations pursue the harmonization of these requirements, aiming at the mutual acceptance of studies conducted in different regions to facilitate international trade and reduce the use of animals in clinical research. Mastitis is one of the most prevalent and costly diseases in dairy cows, and it is associated with negative impacts on milk production and quality, cow welfare, and the profitability of the dairy industry. Normative Instruction No. 26/2009 determines a few rules for conducting studies for registering intramammary antimicrobials for cows with mastitis. However, the regulated sector and researchers report difficulties in following the recommendations of specific guidelines, which complement this regulation due to the peculiarities of Brazil’s production systems. This review article aims to provide subsidies and orientations that scientifically support the conduction and critical analysis of clinical studies proving the efficacy of intramammary products for treating clinical and subclinical mastitis in cows. Considering the need for scientific rigor in the studies, the recommendations available in international guidelines, and the need to adapt the protocols to the current situation of veterinary clinical research in Brazil, this document is intended to contribute to the internal harmonization of experimental protocols that support both the regulated sector and the regulatory authority.

514 Roles of core regulatory noncoding RNAs in bovine Staphylococcus aureus subclinical mastitis

Abstract Staphylococcus aureus (S. aureus) is an opportunistic pathogen frequently associated with subclinical mastitis and accounts for a large proportion of the economic losses due to mastitis on Canadian dairy farms. Despite a plethora of investigations on the molecular mechanisms of mastitis, little information is available on the roles of regulatory noncoding RNAs (ncRNA). This study aimed to uncover the regulatory roles of microRNAs (miRNAs) and long noncoding RNAs (lncRNAs) in the response to subclinical mastitis due to S. aureus of cows. Transcriptome sequencing (RNA-Seq and miRNA-Seq) was conducted on milk somatic cells from 13 cows with S. aureus subclinical mastitis [high somatic cell counts (SCC) of ≥350,000 cells/mL for ≥3 consecutive months and positive for S. aureus only], and 5 healthy cows (low SCC< 100,000 cells/mL for ≥3 consecutive months and negative for mastitis pathogens). RNASeq and smRNASeq nf-core bioinformatics pipelines were used to process the data. Results showed that 97 miRNAs (36 up-regulated and 61 down-regulated) and 1,565 lncRNAs (617 up-regulated and 948 down-regulated) were differentially expressed (DE; FDR< 0.05) between S. aureus subclinical mastitic cows and healthy controls. Competing endogenous networks comprising co-expressed differentially expressed mRNAs (DEGs), miRNAs (DEMs), and lncRNAs (DELs) were constructed. CytoHubba, a Cytoscape plugin, was utilized to identify the top hub regulatory ncRNAs including bta-miR-2387, bta-miR-331, bta-miR-95, bta-miR-744, bta-miR-455, bta-novel-miR-60, bta-miR-3533, bta-miR-500, bta-miR-1249 and bta-novel-miR-66). The results revealed that the main hubs (downregulated bta-miR-2387 and upregulated bta-miR-331) potentially regulate numerous DEGs during S. aureus subclinical mastitis such as NFKB1, IL10RA, IL17RA, TLR10, LOC112442665, LOC112448481 and LOC112442015, etc., and TUNAR, LOC112445429, LOC112444484 and LOC101907369, respectively. Functional analysis of bta-miR-331 target genes revealed roles in several KEGG pathways (e.g., tight junction, bacterial invasion of epithelial cells) and biological processes gene ontology (GO) terms (e.g., cell adhesion, cell locomotion and cell motility). Similarly, roles for bta-miR-2387 in KEGG pathways like JAK-STAT signaling pathway, NOD-like receptor signaling pathway and inflammatory bowel disease, and biological process GO terms such as inflammatory response, neutrophil migration, leucocyte migration and response to cytokine were revealed. MiR-331 has been found to promote cell proliferation, migration, and invasion of breast cancer. Furthermore, bta-miR-2387 has been shown to regulate several immune pathways which aid in improving the movement of spermatids across the epithelium and preleptotene spermatocytes across the blood-testis barrier during spermatogenesis. This supports our findings and suggests that bta-miR-2387 and bta-miR-331 could be pivotal regulators of immune-related genes and pathways during S. aureus subclinical mastitis. Thus, they hold potential as biomarkers for the development of therapeutic and diagnostic tools for managing subclinical mastitis.

Determination of antibacterial and anti-biofilm activities of Terpinen-4-ol loaded polydopamine nanoparticles against Staphylococcus aureus isolates from cows with subclinical mastitis.

Mastitis in cows is one of the most important diseases that give rise to economic losses in dairy farms. Increasing antimicrobial resistance in Staphylococcus aureus, one of the most common causes of mastitis, is a significant health problem. Due to the problems encountered in treating infections caused by resistant strains, developing alternative treatment methods, such as Nanomaterial systems and natural agents, are important. The essential oil of Melaleuca alternifolia is used as an antibacterial and the primary active component is terpinen-4-ol. This study aimed to investigate the antibacterial and anti-biofilm activity of terpinen-4-ol and terpinen-4-ol loaded polydopamine (T-PDA) nanoparticles against S. aureus isolates, which were resistant to at least one group of antibiotics isolated from milk samples of subclinical mastitis cows. The S. aureus strains were identified by biochemical tests and verified with the API Staph kit. The antibiotic susceptibility of the isolates was determined by the disc diffusion method. The broth microdilution method determined the antimicrobial activities of the terpinen-4-ol and T-PDA nanoparticles, and anti-biofilm activities were assessed using the modified crystal violet method. All of the isolates were resistant to benzylpenicillin and susceptible to trimethoprim/sulfamethoxazole. Multi-antibiotic resistance was detected in the 11 S. aureus isolates used in this study. For the terpinen-4-ol and T-PDA nanoparticles, MIC values were determined in the range of 0.125-0.5% (µL/mL) and 0.125-0.25% (µL/mL), respectively. None of the isolates formed biofilms. As a result, it was found that the antibacterial efficacy of the T- PDA nanoparticles was higher against nine of the S. aureus isolates than against the terpinen-4-ol.

Application of cold plasma therapy for managing subclinical mastitis in cows induced by Streptococcus agalactiae, Streptococcus uberis and Escherichia coli

The primary objective of this study was to assess the effectiveness of cold plasma therapy in managing subclinical mastitis in cows caused by Streptococcus agalactiae, Streptococcus uberis and Escherichia coli. After detection of mastitis pathogens, 38 cows were selected for cold plasma therapy for five days. On the fifth day of treatment, the mastitis agents were re-examined and no causative agents were identified. An additional evaluation conducted 28 days later confirmed the absence of mastitis. Cow productivity, milk composition and quality indicators were assessed at the beginning of the experiment and 32 days from the start (28 days after treatment cessation). After the mastitis treatment, the somatic cell count decreased significantly by between 2.89 and 7.09 times, and the milk yield of the cows at the end of the experiment increased from 0.63 kg per day to 2.82 kg per day (P < 0.01). These results highlight the potential of this innovative approach for managing a prevalent disease that causes substantial losses in the dairy industry. Furthermore, they lay the groundwork for expanded research involving larger sample sizes.

Comparative assessment of modern methods of diagnosis of subclinical mastitis in cows

Diseases of the mammary gland, among which mastitis is the most common, cause significant damage to dairy farming. On different farms, from 3 to 50% of lactating cows are sick, and only in 30% of cases the disease manifests itself clinically, and in most cases it has a subclinical course. Early diagnosis of the subclinical stage of mastitis is of great economic, sanitary and technological importance. The effectiveness of timely treatment of sick animals and prevention of the clinical stage of mastitis and ensuring normal milk quality largely depends on it. The study was conducted at the National Research Center of the Ukrainian National Academy of Sciences on 92 lactating cows of the Ukrainian black-spotted breed. Each animal was diagnosed with clinical and subclinical mastitis. Research on subclinical mastitis was carried out using the German milk test and determining the electrical resistance of milk. The diagnostic value of these methods of settling breakdown was monitored. According to the results of the standing test, subclinical mastitis was detected in 30 (32.6%) of 92 lactating cows during the study (49 quarters were affected). Indirect determination of the number of somatic cells using the German milk test allows rapid diagnosis of subclinical mastitis with an accuracy of 84.8%. The use of the "Electronic determinant of mastitis in cows" with the interpretation of the obtained results according to the value of electrical resistance or the difference between the indicators of individual quarters according to the instructions ensures the accuracy of the result in 82.6 and 91.3% of cases, respectively. It is advisable to interpret the indicators of electrical resistance of milk taking into account both indicators. At the same time, cows with indicators of the numerical value of the electrical resistance of milk of 340 (u).o. should be considered healthy. and more and with a difference between the indicators of the quarters of 50 (u).o. and less; for sick animals, the electrical resistance of the secretion of the mammary gland in the range of 260 (u).o. is characteristic. And less with a difference between the largest and smallest indicators of individual quarters of 100 (u).o. and more. A diagnosis of subclinical mastitis can be considered doubtful if the electrical resistance of milk is between 270 and 330 (u).o. and differences between indicators of quarters 60 - 90 (u).o. Key words: cows, subclinical mastitis, electronic mastitis detector, EIMU.

Evaluation of the effectiveness of mastitis tests for the diagnosis of subclinical mastitis in cows

Evaluation of the effectiveness of mastitis tests for the diagnosis of subclinical mastitis in cows

Multi-omics integration identifies regulatory factors underlying bovine subclinical mastitis

BackgroundMastitis caused by multiple factors remains one of the most common and costly disease of the dairy industry. Multi-omics approaches enable the comprehensive investigation of the complex interactions between multiple layers of information to provide a more holistic view of disease pathogenesis. Therefore, this study investigated the genomic and epigenomic signatures and the possible regulatory mechanisms underlying subclinical mastitis by integrating RNA sequencing data (mRNA and lncRNA), small RNA sequencing data (miRNA) and DNA methylation sequencing data of milk somatic cells from 10 healthy cows and 20 cows with naturally occurring subclinical mastitis caused by Staphylococcus aureus or Staphylococcus chromogenes.ResultsFunctional investigation of the data sets through gene set analysis uncovered 3458 biological process GO terms and 170 KEGG pathways with altered activities during subclinical mastitis, provided further insights into subclinical mastitis and revealed the involvement of multi-omics signatures in the altered immune responses and impaired mammary gland productivity during subclinical mastitis. The abundant genomic and epigenomic signatures with significant alterations related to subclinical mastitis were observed, including 30,846, 2552, 1276 and 57 differential methylation haplotype blocks (dMHBs), differentially expressed genes (DEGs), lncRNAs (DELs) and miRNAs (DEMs), respectively. Next, 5 factors presenting the principal variation of differential multi-omics signatures were identified. The important roles of Factor 1 (DEG, DEM and DEL) and Factor 2 (dMHB and DEM), in the regulation of immune defense and impaired mammary gland functions during subclinical mastitis were revealed. Each of the omics within Factors 1 and 2 explained about 20% of the source of variation in subclinical mastitis. Also, networks of important functional gene sets with the involvement of multi-omics signatures were demonstrated, which contributed to a comprehensive view of the possible regulatory mechanisms underlying subclinical mastitis. Furthermore, multi-omics integration enabled the association of the epigenomic regulatory factors (dMHBs, DELs and DEMs) of altered genes in important pathways, such as ‘Staphylococcus aureus infection pathway’ and ‘natural killer cell mediated cytotoxicity pathway’, etc., which provides further insights into mastitis regulatory mechanisms. Moreover, few multi-omics signatures (14 dMHBs, 25 DEGs, 18 DELs and 5 DEMs) were identified as candidate discriminant signatures with capacity of distinguishing subclinical mastitis cows from healthy cows.ConclusionThe integration of genomic and epigenomic data by multi-omics approaches in this study provided a better understanding of the molecular mechanisms underlying subclinical mastitis and identified multi-omics candidate discriminant signatures for subclinical mastitis, which may ultimately lead to the development of more effective mastitis control and management strategies.

Breed and non-genetic risk factors associated with the prevalence of subclinical mastitis in livestock systems of Arauca, Colombian orinoquia

ABSTRACT Subclinical Mastitis (SCM) is caused by several factors associated with the interaction of the individual cow, cow management, and the environment. The aim of this study was to assess the breed and non-genetic risk factors on the prevalence of SCM in cows from the dual-purpose livestock system on the floodplain of Arauca, Colombian Orinoquia. Milk samples were taken from the individual mammary quarters of 481 cows representing 28 different farms where the electrical conductivity (EC) test applied. To determine the factors associated with SCM, a multiple logistic regression analysis was used. The response variable was the SCM presence (1), or absence (0) obtained with the EC test. Breed was included as a genetic risk factor, and as non- genetic risk factors: number of cows in production, daily milk production, lactation month, cow age, climatic period, body condition, and calving number. The factors that were significantly associated with the SCM presence were body condition, climatic period, and breed (p < 0.05). Odds ratio (OR) analysis of significant effects indicates that for each unit increase in body condition, the OR of having animals with SCM is reduced by 71%. In the dry period the OR of animals with SCM increases by 150% compared to the rainy period. Composite breeds reduce the OR of SCM animals by 73%, compared with Indicus-predominance animals. In this study, the occurrence of SCM in extensive management systems in Arauca, Colombian Orinoquia, is determined by the risk factors of breed, climatic period, and body condition.

Evaluation of in vitro antibacterial activities of Vitexnegundo, Phyllanthusemblica and Cymbopogoncitratus against common bacterial pathogens causing subclinical mastitis in cows

Evaluation of in vitro antibacterial activities of Vitexnegundo, Phyllanthusemblica and Cymbopogoncitratus against common bacterial pathogens causing subclinical mastitis in cows

Economic impact of subclinical mastitis treatment in early lactation using intramammary nisin

Treatment of subclinical mastitis (SCM) during lactation is rarely recommended due to concerns related to both antimicrobial usage and costs associated with milk discard. Nisin is a naturally produced antimicrobial peptide with a Gram-positive spectrum that, when given to dairy cows, does not require milk discard. We evaluated the economic impact of treatment of SCM during early lactation using a nisin-based intramammary treatment under different scenarios which included various treatment costs, milk prices, and cure rates. We stochastically simulated the dynamics of SCM detected during the first week of lactation. The net economic impact was expressed in US dollars per case. The probabilities of an event and their related costs were estimated using a model that was based on pathogen-specific assumptions selected from peer-reviewed articles. Nisin cure rates were based on results of pivotal studies included in the FDA approval submission. Based on our model, the average cost of a case of intramammary infection (i.e., only true positive cases) in early lactation was $170 (90th percentage range = $148 to $187), while the cost of a clinical mastitis case was $521 (90th percentage range = $435 to $581). Both estimates varied with etiology, parity, and stage of lactation. When comparing the net cost of SCM cases (i.e., CMT-positive tests) detected during the first week of lactation, nisin treatment generated an average positive economic impact of $19 per CMT-positive case. Use of nisin to treat SCM was beneficial 93% of the time. Based on the sensitivity analysis, treatment would result in an economically beneficial outcome for 95% and 73% of multiparous and primiparous cows, respectively. At the herd level, use of intramammary nisin to treat SCM in cows in early lactation was economically beneficial in most tested scenarios. However, economic impact was highly influenced by factors such as rate of bacteriological cure, cost of treatment, and parity of affected animal. These factors should be considered when deciding to use nisin as a treatment for SCM.

Meta analysis of the prevalence of subclinical mastitis in dairy cattle

Mastitis, which is defined as the inflammation of mammary tissue caused by infectious agents such as bacteria, yeast, fungi and viruses, is considered to be one of the most important problems of dairy enterprises due to reduced milk yield and milk quality. Therefore, studies on mastitis have been continuous from past to present. The presence of too many studies conducted in all around the world in order to estimate the prevalence of mastitis and to determine the factors affecting the disease has necessitated systematic review or meta-analysis studies on this subject. In this study, it was aimed to perform the meta-analysis for the prevalence of cow and udder quarter-based subclinical mastitis in 193 studies conducted around the world, and to determine the effects of some factors on the prevalence of subclinical mastitis using subgroup and meta-regression methods. Because high heterogeneity was detected between studies in the analysis, the random effects model (Der Simonian-Laird method) (Q=15149.869, df=188, p&lt;0.001, I2=98.759; Q=72142.706; df=174, p&lt;0.001; I2=99.774) was used in this study. The publication biases in the study samples were determined by the use of Egger's linear regression test, the Begg and Mazumdar rank correlation test and funnel plots. As a result of the study, the common prevalence of subclinical mastitis in cow and udder quarter-based studies were calculated as 0.46 (95% CI: 0.43-0.48) and 0.32 (95% CI: 0.30-0.34) respectively. The meta-analysis conducted in this study has enabled the elimination of inconsistencies in the prevalence of subclinical mastitis in individual studies conducted around the world, and has provided a stronger and more precise estimate.

The rumen microbiota contributed to the development of mastitis induced by subclinical ketosis

BackgroundMastitis is a serious disease which affects animal husbandry, particularly in cow breeding. The etiology of mastitis is complex and its pathological mechanism is not yet fully understood. Our previous research in clinical investigation has revealed that subclinical ketosis can increase the number of somatic cell counts (SCC) in milk, although the underlying mechanism remains unclear. Recent studies have further confirmed the significant role of mastitis. ResultsIn this study, we aimed to examine the SCC, rumen microbiota, and metabolites in the milkmen of cows with subclinical ketosis. Additionally, we conducted a rumen microbiota transplant into mice to investigate the potential association between rumen microbiota disturbance and mastitis induced by subclinical ketosis in dairy cows. The study has found that cows with subclinical ketosis have a higher SCC in their milk compared to healthy cows. Additionally, there were significant differences in the rumen microbiota and the level of volatile fatty acid (VFA) between cows with subclinical ketosis and healthy cows. Moreover, transplanting the rumen microbiota from subclinical ketosis and mastitis cows into mice can induce mammary inflammation and liver function damage than transplanting the rumen flora from healthy dairy cows. ConclusionsIn addition to the infection of mammary gland by pathogenic microorganisms, there is also an endogenous therapeutic pathway mediated by rumen microbiota. Targeted rumen microbiota modulation may be an effective way to prevent and control mastitis in dairy cows.

Incidence of subclinical mastitis in cows of Peri urban areas of Hyderabad

Incidence of subclinical mastitis in cows of Peri urban areas of Hyderabad

Clinical and Subclinical Bovine Mastitis: Staphylococcus aureus Isolation and Identification from Dairy Farms Located in and Around Hawassa Town, Southern Ethiopia

BACKGROUND: Mastitis is an expensive disease of dairy cattle in most countries, including Ethiopia. The most commonly recovered bacterial pathogen from mastitis milk is _Staphylococcus aureus_ in dairy herds worldwide, with huge economic losses in the dairy industry. OBJECTIVE: To isolate and identify _Staphylococcus aureus_ from bovine mastitis milk. Additionally, risk factors associated with the occurrence of mastitis were determined. METHODS: A cross-sectional study was conducted from March 2021 to August 2021 on dairy farms in and around Hawassa town. A total of 250 lactating cows were examined for clinical and subclinical mastitis from randomly selected dairy farms. Clinical signs and the California Mastitis Test (CMT) were used to identify clinical and subclinical mastitis, respectively. RESULTS: During the study period, 50.8% of cows had mastitis, of which 4.8% and 46% showed clinical and subclinical mastitis, respectively. The quarter-level prevalence was 27.4%; of which the clinical form was 2.9%, while the subclinical mastitis was 24.5%. Logistic regression analysis showed a significant association among cows of different age groups, lactation stages, and farm hygienic status with the occurrence of mastitis (p &lt; 0.05). A bacteriological study targeting _S. aureus_ was conducted with all (n=127) milk samples collected from clinical and subclinical mastitis cows. Bacterial identification targeting _S. aureus_ was done, and this agent was identified in 60 (47.2%) milk samples. This pathogen was found to be higher (47.8%) in subclinical than in clinical (41.6%) mastitis. CONCLUSION: This study showed that mastitis was prevalent in dairy cattle of the study area, with a higher case of _S. aureus_ in subclinical mastitis. However, the recovery of _S. aureus_ in nearly half of the mastitis milk indicated the possible presence of other pathogens. Therefore, further study to recover other potential pathogens commonly causing mastitis can be a good approach.

Case-Control Study: Endogenous Procalcitonin and Protein Carbonylated Content as a Potential Biomarker of Subclinical Mastitis in Dairy Cows.

Procalcitonin (PCT) and protein carbonylated content (PCC) are promising biomarkers for bacterial infection and inflammation in veterinary medicine. This study examined plasma PCT and PCC levels in healthy cows (H) and cows with subclinical mastitis (SCM). A total of 130 cows (65 H and 65 SCM) were included in this study. Blood samples were collected, and plasma was frozen at -80 °C. PCT levels were determined using a bovine procalcitonin ELISA kit, while PCC was measured following the methodology of Levine et al. Statistical analysis revealed a significant difference in PCT levels between H (75.4 pg/mL) and SCM (107.3 pg/mL) cows (p < 0.001) and significantly lower concentrations of PCC in the SCM group (H: 0.102 nmol/mL/mg, SCM: 0.046 nmol/mL/mg; p < 0.001). The PCT cut-off value for distinguishing healthy and subclinical mastitis animals was >89.8 pg/mL (AUC 0.695), with a sensitivity of 66.2% and specificity of 69.2%. PCT showed potential value as a diagnostic tool to help in decision making for subclinical mastitis cases, while PCC requires further studies to investigate the trend of this biomarker during localized pathology.

Characterisation of Milk Microbiota from Subclinical Mastitis and Apparently Healthy Dairy Cattle in Free State Province, South Africa.

Bovine mastitis is an inflammation of the udder tissue of the mammary gland brought on by microbial infections or physical damage. It is characterised by physical, chemical, and biological changes in the udder and milk. While several different bacterial species have been identified as causative agents of mastitis, many subclinical mastitis (SCM) cases remain culture-negative. The aim of this study was to characterise milk microbiota from SCM and apparently healthy dairy cows (non-SCM) by 16S rRNA sequencing. Alpha-diversity metrics showed significant differences between SCM cows and non-SCM counterparts. The beta-diversity metrics in the principal coordinate analysis significantly clustered samples by type (PERMANOVA test, p < 0.05), while non-metric dimensional scaling did not (PERMANOVA test, p = 0.07). The overall analysis indicated a total of 95 phyla, 33 classes, 82 orders, 124 families, 202 genera, and 119 bacterial species. Four phyla, namely Actinobacteriota, Bacteroidota, Firmicutes, and Proteobacteria collectively accounted for more than 97% of all sequencing reads from SCM and non-SCM cow samples. The most abundant bacterial classes were Actinobacteria, Bacilli, Bacteroidia, Clostridia, and Gammaproteobacteria in non-SCM cow samples, whilst SCM cow samples were mainly composed of Actinobacteria, Alphaproteobacteria, Bacilli, Clostridia, and Gammaproteobacteria. Dominant bacterial species in non-SCM cow samples were Anthropi spp., Pseudomonas azotoformans, P. fragi, Acinetobacter guillouiae, Enterococcus italicus, Lactococcus lactis, whilst P. azotoformans, Mycobacterium bovis, P. fragi, Acinetobacter guillouiae, and P. koreensis were dominant in the SCM cow samples. The current study found differences in bacterial species between SCM and non-SCM cow milk; hence, the need for detailed epidemiological studies.

The direct microscopic examination of somatic cell count to detect sub-clinical mastitis in cows of Diyala province

Background Udder Inflammation is still one of the most significant economic issues that may affect milk production. Methods: Several tests were used to detect the pH of milk, such as the aerial mastitis test, Whiteside test, chloride test, Bovi-mastitis test (Card test), Somatic cell count, and bacterial culturing. Results showed that 32% of cows suffered abnormalities in the consistency of milk, whereas 68% of cows passed through subclinical mastitis. Furthermore, the results also showed that 80 % of cows were affected by Staph. Aureus, compared to other bacterial species Conclusions: According to our findings, subclinical and clinical mastitis is significant in Diyala Province, and infectious and environmental pathogens are involved. Moreover, locally manufactured Arial mastitis test, Whiteside test, and the imported Bovi card test are appropriate tests for the early diagnosis of subclinical mastitis in cattle. Staph. Aureus was more prevalent than other inflammatory infections and ambient pathogens in cases of bovine mastitis. Keywords: Detection; mastitis clinical and sub-clinical; Dairy cows; Diyala Province.

Molecular regulatory mechanism of key LncRNAs in subclinical mastitic cows with folic acid supplementation

BackgroundFolic acid is a water-soluble B vitamin (B9), which is closely related to the body’s immune and other metabolic pathways. The folic acid synthesized by rumen microbes has been unable to meet the needs of high-yielding dairy cows. The incidence rate of subclinical mastitis in dairy herds worldwide ranged between 25%~65% with no obvious symptoms, but it significantly causes a decrease in lactation and milk quality. Therefore, this study aims at exploring the effects of folic acid supplementation on the expression profile of lncRNAs, exploring the molecular mechanism by which lncRNAs regulate immunity in subclinical mastitic dairy cows.ResultsThe analysis identified a total of 4384 lncRNA transcripts. Subsequently, differentially expressed lncRNAs in the comparison of two groups (SF vs. SC, HF vs. HC) were identified to be 84 and 55 respectively. Furthermore, the weighted gene co-expression network analysis (WGCNA) and the KEGG enrichment analysis result showed that folic acid supplementation affects inflammation and immune response-related pathways. The two groups have few pathways in common. One important lncRNA MSTRG.11108.1 and its target genes (ICAM1, CCL3, CCL4, etc.) were involved in immune-related pathways. Finally, through integrated analysis of lncRNAs with GWAS data and animal QTL database, we found that differential lncRNA and its target genes could be significantly enriched in SNPs and QTLs related to somatic cell count (SCC) and mastitis, such as MSTRG.11108.1 and its target gene ICAM1, CXCL3, GRO1.ConclusionsFor subclinical mastitic cows, folic acid supplementation can significantly affect the expression of immune-related pathway genes such as ICAM1 by regulating lncRNAs MSTRG.11108.1, thereby affecting related immune phenotypes. Our findings laid a ground foundation for theoretical and practical application for feeding folic acid supplementation in subclinical mastitic cows.

Biochemical and Computational Assessment of Acute Phase Proteins in Dairy Cows Affected with Subclinical Mastitis.

Subclinical mastitis (SCM) is a predominant form of mastitis wherein major visible signs of disease are absent. The present study aimed to determine acute phase proteins (APPs) like ferritin, C-reactive protein (CRP), and microalbumin (Malb) in 135 composite milk and serum samples of healthy (n = 25) and SCM (n = 110) cows. As bovine mastitis is an inflammatory disease, the present study also aimed at finding novel anti-inflammatory compounds from natural sources by repurposing approach using computational studies. The findings of the present study revealed substantial elevation (p < 0.001) in milk SCC and an increase in ferritin, CRP, and Malb (p < 0.001) in milk and sera of the SCM group as compared to healthy animals. Receiver operating characteristics of milk SCC, milk, and serum APPs unraveled statistically substantial alteration (p < 0.001). Further, SCC was correlated with milk APPs ferritin (r = 0.26 **, p < 0.002), CRP (r = 0.19 *, p < 0.02), and Malb (r = 0.21 *, p < 0.01). Additionally, milk SCC was correlated with serum ferritin (r = 0.28 **, p < 0.001), CRP (r = 0.16, p > 0.05), and Malb (r = 0.16, p > 0.05). The findings of molecular docking revealed that Chaetoglobosin U was the most effective molecule that showed the highest binding affinity (kcal/mol) of -10.1 and -8.5 against ferritin and albumin. The present study concluded that the estimation of cow-side tests, SCC, and APPs in milk/serum is suitable to detect SCM and screening herd community. Furthermore, Chaetoglobosin U could be developed as a promising anti-inflammatory inhibitor; however, further studies are required to validate these findings.