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Veterinary Research Jun 2024Bovine mastitis remains a major disease in cattle world-wide. In the mammary gland, mammary epithelial cells (MEC) are sentinels equipped with receptors allowing them to...
Bovine mastitis remains a major disease in cattle world-wide. In the mammary gland, mammary epithelial cells (MEC) are sentinels equipped with receptors allowing them to detect and respond to the invasion by bacterial pathogens, in particular Escherichia coli. Lipopolysaccharide (LPS) is the major E. coli motif recognized by MEC through its interaction with the TLR4 receptor and the CD14 co-receptor. Previous studies have highlighted the role of soluble CD14 (sCD14) in the efficient recognition of LPS molecules possessing a full-length O-antigen (LPSS). We demonstrate here that MEC are able to secrete CD14 and are likely to contribute to the presence of sCD14 in milk. We then investigated how sCD14 modulates and is required for the response of MEC to LPSS. This study highlights the key role of sCD14 for the full activation of the Myd88-independent pathway by LPSS. We also identified several lncRNA that are activated in MEC in response to LPS, including one lncRNA showing homologies with the mir-99a-let-7c gene (MIR99AHG). Altogether, our results show that a full response to LPS by mammary epithelial cells requires sCD14 and provide detailed information on how milk sCD14 can contribute to an efficient recognition of LPS from coliform pathogens.
Topics: Animals; Lipopolysaccharide Receptors; Cattle; Epithelial Cells; Lipopolysaccharides; Female; Mammary Glands, Animal; Mastitis, Bovine; Milk
PubMed: 38867337
DOI: 10.1186/s13567-024-01329-3 -
Microbiology Resource Announcements Jun 2024species complex members, particularly , are common bovine clinical mastitis pathogens and often the cause of hospital- and community-acquired infections in humans....
species complex members, particularly , are common bovine clinical mastitis pathogens and often the cause of hospital- and community-acquired infections in humans. Here, we present 148 draft genome assemblies and annotations of species complex members from bovine and human hosts in Canada.
PubMed: 38864639
DOI: 10.1128/mra.00132-24 -
Applied and Environmental Microbiology Jun 2024is an important emerging pathogen of cattle and bison, but our understanding of the genetic basis of its interactions with its host is limited. The aim of this study...
UNLABELLED
is an important emerging pathogen of cattle and bison, but our understanding of the genetic basis of its interactions with its host is limited. The aim of this study was to identify genes of required for interaction and survival in association with host cells. One hundred transposon-induced mutants of the type strain PG45 were assessed for their capacity to survive and proliferate in Madin-Darby bovine kidney cell cultures. The growth of 19 mutants was completely abrogated, and 47 mutants had a prolonged doubling time compared to the parent strain. All these mutants had a similar growth pattern to the parent strain PG45 in the axenic media. Thirteen genes previously classified as dispensable for the axenic growth of were found to be essential for the growth of in association with host cells. In most of the mutants with a growth-deficient phenotype, the transposon was inserted into a gene involved in transportation or metabolism. This included genes coding for ABC transporters, proteins related to carbohydrate, nucleotide and protein metabolism, and membrane proteins essential for attachment. It is likely that these genes are essential not only but also for the survival of in infected animals.
IMPORTANCE
causes chronic bronchopneumonia, mastitis, arthritis, keratoconjunctivitis, and reproductive tract disease in cattle around the globe and is an emerging pathogen in bison. Control of mycoplasma infections is difficult in the absence of appropriate antimicrobial treatment or effective vaccines. A comprehensive understanding of host-pathogen interactions and virulence factors is important to implement more effective control methods against . Recent studies of other mycoplasmas with cell culture models have identified essential virulence genes of mycoplasmas. Our study has identified genes of required for survival in association with host cells, which will pave the way to a better understanding of host-pathogen interactions and the role of specific genes in the pathogenesis of disease caused by .
PubMed: 38864628
DOI: 10.1128/aem.00687-24 -
Journal of Animal Science Jun 2024Mastitis is an important disease with economic and welfare implications in both clinical and subclinical states. The aim of this research was to sequence the...
Mastitis is an important disease with economic and welfare implications in both clinical and subclinical states. The aim of this research was to sequence the hypervariable V4 region of the 16S rRNA gene to describe the microbial diversity and taxonomy of milk from clinically healthy ewes (Rambouillet, WF = 9; Hampshire, BF = 5). Experimental ewes represented a subset of a larger study assessing the impacts of divergent dietary zinc (Zn) concentrations [1× National Academics of Sciences, Engineering, and Medicine (NASEM) recommendations = CON or 3× NASEM recommendations = ZnTRT] throughout late gestation and lactation. Milk was collected at four periods during early lactation (18 - 24 h, 7 d, 14 d, and 21 d postpartum) and at weaning (84 ± 14 d postpartum). Somatic cell counts (SCC) were quantified, averaged, and classed (low: < 500 × 103; medium: 500 × 103 - 100 × 104; high: > 100 × 104 cells/mL). Milk samples (n = 67) were sequenced to identify bacteria and archaea; the most abundant phyla were Actinobacteria, Bacteroidetes, Cyanobacteria, Euryarchaeota, Firmicutes, Fusobacteria, Lentisphaerae, Proteobacteria, Spirochaetes, Tenericutes, Saccharibacteria TM7, and Verrucomicrobia. Mastitis pathogens were among the most relatively abundant genera, including Staphylococcus, Mannheimia, Corynebacterium, and Pseudomonas. Effects of breed, dietary Zn concentration, SCC class, and their two-way interactions on milk microbiome diversity and taxonomy were assessed within early lactation (using a repeated measures model) and weaning samples. Alpha-diversity metrics included Pielou's evenness, Faith's phylogenetic diversity, and Shannon's entropy indices. Main and interactive effects between Zn treatment, breed, SCC class, and period were variable in early lactation and not evident in weaning samples. Milk from BF ewes had increased Faith's phylogenetic diversity and Shannon's entropy, and differed in unweighted UniFrac composition (P ≤ 0.10). Milk from CON ewes had a reduced rate of composition change through early lactation (P = 0.02) indicating greater microbiome stability than ZnTRT ewe milk. These results support that milk is not sterile, and breed, dietary Zn concentration, and SCC class variably affect the milk microbiome. Findings from the current study provide important foundational insights into the effects of increased dietary Zn supplementation on longitudinal changes in the milk microbiome and associations with mammary gland health and mastitis.
PubMed: 38864526
DOI: 10.1093/jas/skae163 -
Frontiers in Veterinary Science 2024Bovine mastitis is one of the most common diseases of dairy cattle. Even though different infectious microorganisms and mechanical injury can cause mastitis, bacteria... (Review)
Review
Bovine mastitis is one of the most common diseases of dairy cattle. Even though different infectious microorganisms and mechanical injury can cause mastitis, bacteria are the most common cause of mastitis in dairy cows. Staphylococci, streptococci, and coliforms are the most frequently diagnosed etiological agents of mastitis in dairy cows. Staphylococci that cause mastitis are broadly divided into and non-aureus staphylococci (NAS). NAS is mainly comprised of coagulase-negative species (CNS) and some coagulase-positive and coagulase-variable staphylococci. Current staphylococcal mastitis control measures are ineffective, and dependence on antimicrobial drugs is not sustainable because of the low cure rate with antimicrobial treatment and the development of resistance. Non-antimicrobial effective and sustainable control tools are critically needed. This review describes the current status of and NAS mastitis in dairy cows and flags areas of knowledge gaps.
PubMed: 38863450
DOI: 10.3389/fvets.2024.1356259 -
Reproduction in Domestic Animals =... Jun 2024The impact of beta-carotene on cattle fertility has been investigated in various studies; however, consensus on this issue has not been reached. In the present study, we... (Meta-Analysis)
Meta-Analysis
The impact of beta-carotene on cattle fertility has been investigated in various studies; however, consensus on this issue has not been reached. In the present study, we systematically reviewed and meta-analysed 29 publications conducted between 1984 and 2022, focusing on seven fertility measures, clinical mastitis and milk yield in cows. We did not find statistically significant results in 8 out of 11 parameters (p > .05). Statistically significant results were observed for milk yield (MD: 216.25 kg in 305 days, p = .01, CI: 50.73-381.77), pregnancy at first service (OR: 1.38 CI: 1.08-1.76, p = .01) and clinical mastitis (OR: 0.59, CI: 0.44-0.80, p = .006) in favour of beta-carotene supplementation. The meta-regression revealed significant effects of 'plasma beta-carotene levels' on 'service to per pregnancy' and dose on 'milk yield' (p = .04 and p = 0). In binary outcomes, 'dose × day' and 'plasma beta-carotene concentration in the control group' positively influenced pregnancy at first service (p = .02 and .03). In conclusion, given the positive point direction observed for some variables and insignificant results for others, there is a need for more studies. We note the very high heterogeneity of outcomes and suggest caution in interpreting results.
Topics: Animals; beta Carotene; Female; Cattle; Lactation; Milk; Mastitis, Bovine; Pregnancy; Dietary Supplements; Fertility
PubMed: 38860761
DOI: 10.1111/rda.14634 -
International Immunopharmacology Jun 2024Mastitis, one of the most significant problems in women, is commonly caused by pathogens, especially Staphylococcus aureus (S.aureus). Schisandrin B (SCB), the main...
Mastitis, one of the most significant problems in women, is commonly caused by pathogens, especially Staphylococcus aureus (S.aureus). Schisandrin B (SCB), the main abundant derivatives from Schisandra chinensis, has been proven to have the ability to inhibiting inflammation and bacteria. However, few relevant researches systematically illustrate the role SCB in the treatment of mastitis. The aim of the present study is to demonstrate the mechanism that SCB functions in reducing pathological injury to the mammary gland in treating S.aureus-induced mastitis. H&E staining was used to identify pathological changes and injuries in mastitis. The levels of cytokines associated with inflammation were detected by ELISA. Key signals relevant to ferroptosis and Nrf2 signaling pathway were tested by western blot analysis and iron assay kit. Compared with the control group, inflammation-associated factors, such as IL-1β, TNF-α, MPO activity, increased significantly in S. aureus-treated mice. However, these changes were inhibited by SCB. Ferroptosis-associated factors Fe and MDA increased significantly, and GSH, GPX4 and ferritin expression decreased markedly in S. aureus-treated mice. SCB treatment could attenuate S.aureus-induced ferroptosis. Furthermore, SCB increase SIRT1 and SLC7A11 expression and down-regulated p53 expression and NF-κB activation. In conclusion, SCB alleviates S.aureus-induced mastitis via up-regulating SIRT1/p53/SLC7A11 signaling pathway, attenuating the activation of inflammation-associated cytokines and ferroptosis in the mammary gland tissues.
PubMed: 38852519
DOI: 10.1016/j.intimp.2024.112430 -
Journal of Dairy Science Jun 2024To comply with antibiotic restriction policies in the European Union, internal teat sealants (TS) are increasingly used at drying off (DO) in selective dry cow treatment...
To comply with antibiotic restriction policies in the European Union, internal teat sealants (TS) are increasingly used at drying off (DO) in selective dry cow treatment protocols to maintain udder health. Post-calving TS residue attachment to milking equipment and associated cleaning difficulties is a reason for some farmers to stay away from blanket TS use. Our objective was therefore to improve insight in TS excretion visibility and to compare quantity, pattern, and presence versus absence of TS excretion post-calving between the typical 2 cow categories at DO: High (H) and Low (L) SCC cows, treated with antibiotic (AB) plus TS (H-ABTS) or TS only (L-TS), respectively. In herds in the Netherlands (n = 3), and Germany (n = 4), cows were enrolled at DO, and categorized as H-ABTS (n = 93), or L-TS (n = 99). Post-calving, quarter level TS visibility, quantities, patterns, and percentage of TS infused and excreted post-calving were recorded from 50 mL of pre-milk of every quarter at each of the first 15 or 16 milkings. Udder quarter health status was determined by bacteriological culture and somatic cell counting of quarter milk samples taken at DO and at d 3 post-calving and by clinical mastitis incidence from DO until 30 DIM. Univariable and multivariable models were created to explore associations of TS excretion presence versus absence at the first 3 milkings. Irrespective of SCC category, both laboratory personnel, and farmers saw TS residues at the first milking in an equal 72% of quarters. Compared with laboratory as the gold standard, farmer sensitivity to spot TS in pre-milk was 74.5% at the first milking, decreasing to a maximum of 8.3% at the last 3 milking's. At the first milking, TS excretion quantities showed a bimodal distribution pattern and the mean percentage of TS infused (3.83 g) that was excreted in pre-milk at the first milking, was higher in the L-TS (45.5%) compared with the H-ABTS cow category (32%). At the second and third milking, mean adjusted TS percentage excreted was higher in the H-ABTS (8.5% and 1.8%, respectively) compared with the L-TS category (4.6% and 0.4% respectively). The multivariable model of the first 3 milkings showed parity at both the first and second milking, and study group at both the second and third milking, was significantly associated to TS presence. The univariable model showed no association between TS presence at the first milking and udder health. In conclusion, in pre-milk of the first milking, TS residue excretion was bimodal, higher in L-TS cows, more likely present in multiparous cows, and not associated with udder health. At the second and third milking, excretion was higher in H-ABTS cows and TS presence was only more likely in multiparous cows at the second milking.
PubMed: 38851577
DOI: 10.3168/jds.2023-24289 -
Animal : An International Journal of... Jun 2024Biosecurity plays a crucial role in preventing the introduction of infectious diseases to a herd as well as the spread of diseases within or between animals and herds....
Biosecurity plays a crucial role in preventing the introduction of infectious diseases to a herd as well as the spread of diseases within or between animals and herds. In particular, biosecurity measures are crucial for maintaining animal health and reducing the need for the application of antibiotic substances for fighting the rising antibiotic resistance. The object of this cross-sectional study was to investigate the presence of biosecurity measures and their association with milk quality parameters, with a special focus on somatic cell count (SCC) - an indicator for udder health -, in small-scale mountain dairy farms. Therefore, for the very first time, the CLASSYFARM system was considered, which is a computer platform integrated into the Italian national veterinary portal, that processes a significant amount of data from various sources collected in the field or from other information systems (e.g. animal welfare, health status, biosecurity, antimicrobial use, slaughterhouse information). A total of 169 dairy farms were included in the study. Biosecurity measures, based on 15 questions required in the CLASSYFARM welfare assessment protocol, as well as information about husbandry systems, milking systems and pasture practices were gathered and combined with milk yield data, provided by the South Tyrolean dairy association. Farms only scored 44.00 points on average in a scoring system from 0.00 to 100.00 points that was be able to summarize 15 different biosecurity measures in one index. Our results show a clear negative correlation (-0.713) between the biosecurity index and somatic cell score (SCS) indicating that a higher level of biosecurity, which reflects the presence of biosecurity measures within a farm, is associated with lower SCC levels. Furthermore, we found significant correlations between SCS and milk production (-0.629), confirming that udder health is linked to higher milk production. Fat, protein, and the fat-to-protein ratio showed a positive correlation with SCS (0.281, 0.146, 0.106), likely to be caused by a concentration shift effect (dilution effect). Husbandry system, breed, milking system, and pasture practices seem to have an impact as well, but the main factor was the biosecurity score. This study highlights the importance of implementing biosecurity measures for ensuring animal health and thus productivity and quality in milk production, even in small-scale farms, which are characterized by limited structure availability and smaller herds compared to big dairy enterprises in the lowlands.
Topics: Animals; Dairying; Cattle; Cross-Sectional Studies; Milk; Italy; Female; Animal Husbandry; Cell Count; Animal Welfare; Farms; Mastitis, Bovine
PubMed: 38850577
DOI: 10.1016/j.animal.2024.101188 -
BMC Veterinary Research Jun 2024Staphylococcus aureus can colonize and infect a variety of animal species. In dairy herds, it is one of the leading causes of mastitis cases. The objective of this study...
BACKGROUND
Staphylococcus aureus can colonize and infect a variety of animal species. In dairy herds, it is one of the leading causes of mastitis cases. The objective of this study was to characterize the S. aureus isolates recovered from nasal swabs of 249 healthy cows and 21 breeders of 21 dairy farms located in two provinces of Algeria (Tizi Ouzou and Bouira).
METHODS
The detection of enterotoxin genes was investigated by multiplex PCRs. Resistance of recovered isolates to 8 antimicrobial agents was determined by disc-diffusion method. The slime production and biofilm formation of S. aureus isolates were assessed using congo-red agar (CRA) and microtiter-plate assay. Molecular characterization of selected isolates was carried out by spa-typing and Multi-Locus-Sequence-Typing (MLST).
RESULTS
S. aureus was detected in 30/249 (12%) and 6/13 (28.6%) of nasal swabs in cows and breeders, respectively, and a total of 72 isolates were recovered from positive samples (59 isolates from cows and 13 from breeders). Twenty-six of these isolates (36.1%) harbored genes encoding for staphylococcal enterotoxins, including 17/59 (28.8%) isolates from cows and 9/13 (69.2%) from breeders. Moreover, 49.1% and 92.3% of isolates from cows and breeders, respectively, showed penicillin resistance. All isolates were considered as methicillin-susceptible (MSSA). Forty-five (76.3%) of the isolates from cows were slime producers and 52 (88.1%) of them had the ability to form biofilm in microtiter plates. Evidence of a possible zoonotic transmission was observed in two farms, since S. aureus isolates recovered in these farms from cows and breeders belonged to the same clonal lineage (CC15-ST15-t084 or CC30-ST34-t2228).
CONCLUSIONS
Although healthy cows in this study did not harbor methicillin-resistant S. aureus isolates, the nares of healthy cows could be a reservoir of enterotoxigenic and biofilm producing isolates which could have implications in human and animal health.
Topics: Animals; Cattle; Staphylococcus aureus; Biofilms; Algeria; Enterotoxins; Female; Staphylococcal Infections; Drug Resistance, Bacterial; Anti-Bacterial Agents; Carrier State; Dairying; Cattle Diseases
PubMed: 38849892
DOI: 10.1186/s12917-024-04103-x