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1.
Schweiz Arch Tierheilkd ; 161(9): 533-544, 2019 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-31488394

RESUMO

INTRODUCTION: The aim of the present study was to determine the effects of selective dry cow treatment (SDCT) on udder health in Swiss dairy farms compared to a blanket dry cow treatment (BDCT). Cows with a somatic cell count (SCC) of less than 250'000 cells/ml and after BDCT in the previous dry period were selected. These animals received a SDCT in the subsequent dry period. Cows with less than 150,000 cells/ml or a negative California mastitis test (CMT) received either no treatment (group oB) or an internal teat sealant (group ZV) in all teats. Cows with more than 150,000 cells/ml or a positive CMT were treated with antibiotics and teat sealants (group ZV+AB). The SCC before and after the dry period were determined. In addition, the incidence of mastitis treatments in the dry period and the first 100 days of the following lactation as well as rates of new intramammary inflammations and healing thereof were determined. Data from 115 cows were available for evaluation. The SCC postpartum of all cows after SDCT did not differ from those after BDCT in the previous year. In the group oB the SCC was significantly higher than in the previous year. While the group ZV+AB showed a significant decrease of SCC during the dry period, the other two groups showed an increase (p < 0.0001). In the group oB, the proportion of mastitis treatments increased from 0% after BDCT to 28% after SDCT without any udder treatment (p < 0.05). Due to the increasing problem of antimicrobial resistance, SDCT is a valuable alternative to the BDCT. In the present study the antibiotic consumption could be reduced by 63%, while the udder health after SDCT did not deteriorate. If cows with low SCC are dried off without antibiotics the end of lactation, it is beneficial to protect the udder during the dry period with a teat sealant.


Assuntos
Indústria de Laticínios/métodos , Glândulas Mamárias Animais , Mastite Bovina/prevenção & controle , Animais , Antibacterianos/administração & dosagem , Bovinos , Contagem de Células/veterinária , Feminino , Incidência , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/tratamento farmacológico , Mastite Bovina/epidemiologia , Suíça/epidemiologia
2.
Vet Immunol Immunopathol ; 214: 109890, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31378218

RESUMO

Bovine mastitis is a significant cause of economic losses in the dairy industry. Staphylococcus aureus is one of the most common contagious mastitis pathogens, whereas Staphylococcus chromogenes increasingly became a significant cause of subclinical mastitis in dairy cows. Current mastitis control measures are not effective on all mastitis pathogens. There is no effective vaccine to control Staphylococcal mastitis in dairy cows. The objective of this study was to evaluate the immune responses and protection in dairy cows vaccinated with S. aureus surface proteins (SASP) or S. chromogenes surface proteins (SCSP). We divided eighteen Holstein dairy cows randomly into three groups of 6 animals each. We vaccinated group 1 and 2 animals with SASP and SCSP with Emulsigen-D adjuvant, respectively. We injected control (group 3) animals with PBS (pH 7.2) in Emulsigen®-D. We vaccinated animals three times at 28 and 14 days before drying off, and at dry off. Two weeks after the third vaccination, we challenged each animal by dipping all teats in S. aureus culture suspension once daily for 14 consecutive days. We evaluated milk or mammary secretion and serum antibody titers during vaccination and challenge periods. We evaluated milk samples for the number of bacteria shedding and somatic cell counts (SCC). Out of six cows vaccinated with SASP, one cow was removed from the study due to injury, two were infected clinically, another two were infected subclinically, and the remaining cow was not infected. No SCSP vaccinated cows developed clinical or subclinical mastitis. Out of six control cows, two developed clinical mastitis whereas four were infected subclinically. The SCSP vaccine cross-protected against S. aureus mastitis and reduced number of S. aureus shedding in milk. We concluded that the SCSP is a promising vaccine to control Staphylococcal mastitis in dairy cows.


Assuntos
Mastite Bovina/prevenção & controle , Proteínas de Membrana/imunologia , Infecções Estafilocócicas/veterinária , Vacinas Antiestafilocócicas/imunologia , Staphylococcus aureus/imunologia , Animais , Derrame de Bactérias , Bovinos , Contagem de Células , Indústria de Laticínios , Feminino , Proteínas de Membrana/administração & dosagem , Leite/microbiologia , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/prevenção & controle , Vacinação
3.
Vet Immunol Immunopathol ; 212: 1-8, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31213246

RESUMO

Bovine mastitis caused by Staphylococcus aureus is a serious problem in dairy production and effective immunoprophylaxis is an unmet goal so far. The objective of this work was to assess the humoral immune response of heifer calves against two recombinant S. aureus antigens: Clumping factor A (ClfA) and Fibronectin Binding Protein A (FnBPA), formulated with a novel adjuvant based on cationic liposomes (Lip) and CpG oligodeoxynucleotides (CpG-ODN). Six groups of 6-8 months old heifer calves received three doses biweekly of antigens, formulated with Al(OH)3, liposomes, CpG-ODN or Lip + CpG-ODN. Animals also received a fourth dose after a year (day 410) and a booster before calving. The administration of Al(OH)3+FnBPA/ClfA and Lip + FnBPA/ClfA + CpG-ODN induced the highest specific IgG levels, after the first 3 doses and induced a fast increase of antibodies after the fourth dose. All the formulations stimulated the production of specific IgG1, after the third and fourth dose. Specific IgG2 for both proteins was only stimulated after the fourth dose by Lip + FnBPA/ClfA + CpG-ODN. Pre-calving immunisation with Lip + FnBPA/ClfA + CpG-ODN led to the highest IgG levels during the calving period and to the production of the IgG2 subclass. The formulation was also able to stimulate the highest antibody levels in milk, 30 and 45 days after pre-calving booster. The combination of liposomes and CpG-ODN as adjuvant for a subunit vaccine, together with the immunisation schedule described, induced a strong humoral immune response with production of specific IgG2. The formulation demonstrated to induce immune memory allowing the application of a single pre-calving booster to maintain high antibody levels throughout the period of increased susceptibility to intramammary infections.


Assuntos
Antígenos de Bactérias/imunologia , Imunidade Humoral , Mastite Bovina/prevenção & controle , Oligodesoxirribonucleotídeos/farmacologia , Adjuvantes Imunológicos/administração & dosagem , Fatores Etários , Animais , Anticorpos Antibacterianos/sangue , Bovinos , Imunoglobulina G/sangue , Memória Imunológica , Lipossomos/farmacologia , Mastite Bovina/imunologia , Mastite Bovina/microbiologia , Staphylococcus aureus , Vacinação , Soro do Leite/imunologia
4.
J Dairy Sci ; 102(7): 6682-6698, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31128869

RESUMO

Our objective was to compare the composition of bedding materials and manure, cow welfare and hygiene assessments, measures of milk production and quality, and incidence of mastitis during a 3-yr trial with lactating Holstein cows housed in a freestall barn containing 4 identical pens with 32 freestalls/pen. Bedding systems evaluated included deep-bedded organic manure solids (DBOS), shallow-bedded manure solids spread over mattresses (MAT), deep-bedded recycled sand (RSA), and deep-bedded new sand (NSA). The experiment was designed as a 4 × 4 Latin square with 4 bedding systems and 4 experimental periods, but was terminated after 3 yr following discussions with the consulting statistician; therefore, data were analyzed as an incomplete Latin square. A total of n = 734 mostly primiparous cows (n = 725 primiparous, n = 9 multiparous; 224 to 267 cows/yr) were enrolled in the trial. Before placement in freestalls, organic solids (OS) exhibited lower concentrations of dry matter (36.5 vs. 94.3%), and greater concentrations of volatile solids, C, N, NH4-N, P, water-extractable P, K, and S compared with RSA or NSA. Cow comfort index was greater for sand-bedded systems compared with those using OS (88.4 vs. 82.8%). Cows bedded in systems using OS (DBOS and MAT) exhibited greater mean hock scores (1 = no swelling, no hair loss; 2 = no swelling, bald area on hock) than those bedded in sand (1.25 vs. 1.04), but this effect was entirely associated with use of mattresses (MAT), which differed sharply from DBOS (1.42 vs. 1.07). Generally, hygiene scores for legs, flanks, and udders were numerically similar for DBOS, NSA, and RSA bedding systems, and differences between bedding systems were associated entirely with MAT, yielding detectable contrasts between MAT and DBOS for legs (2.94 vs. 2.20), flanks (2.34 vs. 1.68), and udders (1.83 vs. 1.38). No significant contrast comparing bedding systems was detected for measures of milk production or quality. Documented cases of clinical mastitis requiring treatment ranged from a low rate of 7.4 cases/yr for RSA to a high of 23.1 cases/yr for DBOS, based on a mean enrollment of 60.7 to 63.0 cows/treatment per yr. Cows bedded with OS exhibited a greater incidence of mastitis than those bedded with sand (19.0 vs. 8.4 cases/yr), but no differences were observed for comparisons within individual bedding-material types. Collectively, these results generally favored use of sand-bedding materials over systems using OS.


Assuntos
Bovinos , Indústria de Laticínios/métodos , Abrigo para Animais , Dióxido de Silício , Criação de Animais Domésticos , Animais , Feminino , Higiene , Incidência , Lactação , Mastite Bovina/epidemiologia , Mastite Bovina/prevenção & controle , Distribuição Aleatória
5.
Microb Pathog ; 131: 15-21, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30930221

RESUMO

Staphylococcus aureus is a major pathogen of subclinical bovine mastitis that usually is chronic and recurrent, which has been related to its ability to internalize into bovine mammary epithelial cells (bMECs). Previously, we reported that short and medium fatty acids and cholecalciferol reduce S. aureus internalization into pretreated-bMECs with these molecules suggesting a role as immunomodulatory agents. Hence, we assessed the role of sodium butyrate (NaB), sodium octanoate (NaO) and cholecalciferol on S. aureus adhesin expression and its internalization into bMECs. S. aureus pre-treated 2 h with 0.5 mM or 2 mM NaB showed a reduction in internalization into bMECs (∼35% and ∼55%; respectively), which coincided with a down-regulated expression of clumping factor B (ClfB). Also, the S. aureus internalization reduction by 2 mM NaB (2 h) agreed with a down-regulated expression of sdrC. Moreover, the 2 mM NaB (24 h) pre-treatment induced bacterial internalization (∼3-fold), which was related with an up-regulation of spa, clfB and sdrC genes. Also, NaO (0.25 mM and 1 mM) only reduced S. aureus internalization when bacteria were grown 2 h with this molecule but there was no relationship with adhesin expression. In addition, cholecalciferol (50 nM) reduced bacteria internalization at similar levels (∼50%) when bacteria were grown 2 and 24 h in broth supplemented with this compound, which correlated with spa and sdrC mRNA expression down-regulated at 2 h, and fnba and clfB mRNA expression decreased at 24 h. In conclusion, our data support the fact that fatty acids and cholecalciferol regulate adhesin gene expression as well as bacteria internalization in nonprofessional phagocytic cells, which may lead to development of anti-virulence agents for control of pathogens.


Assuntos
Adesinas Bacterianas/genética , Células Epiteliais/imunologia , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Glândulas Mamárias Animais/imunologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética , Adesinas Bacterianas/efeitos dos fármacos , Animais , Proteínas de Bactérias/genética , Ácido Butírico , Caprilatos/farmacologia , Bovinos , Linhagem Celular , Colecalciferol/farmacologia , Regulação para Baixo/efeitos dos fármacos , Células Epiteliais/microbiologia , Ácidos Graxos/farmacologia , Feminino , Gentamicinas/farmacologia , Imunidade Inata/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Imunomodulação , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/imunologia , Mastite Bovina/microbiologia , Mastite Bovina/prevenção & controle , RNA Mensageiro/metabolismo , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/prevenção & controle , Fatores de Virulência/genética
6.
Prev Vet Med ; 166: 78-85, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30935508

RESUMO

The objective of this study was to evaluate and compare different combinations of intervention strategies for contagious or opportunistic subclinical and clinical intramammary infections (IMI). We simulated two different Danish dairy cattle herds with ten different intervention strategies focusing on cow-specific treatment or culling, including three baseline strategies without subclinical interventions. In one herd, the main causative pathogen of IMI was Staphylococcus (S.) aureus. In the other herd, Streptococcus (St.) agalactiae was the main causative agent. For both herds, we investigated costs and effectiveness of all ten intervention strategies. Intervention strategies consisted of measures against clinical and subclinical IMI, with baselines given by purely clinical intervention strategies. Our results showed that strategies including subclinical interventions were more cost-effective than the respective baseline strategies. Increase in income and reduction of IMI cases came at the cost of increased antibiotic usage and an increased culling rate in relation to IMI. However, there were differences between the herds. In the St. agalactiae herd, the clinical intervention strategy did not seem to have a big impact on income and number of cases. However, intervention strategies which included cow-specific clinical interventions led to a higher income and lower number of cases in the S. aureus herd. The results show that intervention strategies including interventions against contagious or opportunistic clinical and subclinical IMI can be highly cost-effective, but should be herd-specific.


Assuntos
Controle de Doenças Transmissíveis/métodos , Indústria de Laticínios , Mastite Bovina/prevenção & controle , Infecções Estafilocócicas/veterinária , Infecções Estreptocócicas/veterinária , Animais , Infecções Assintomáticas/economia , Bovinos , Dinamarca , Feminino , Mastite Bovina/economia , Mastite Bovina/microbiologia , Infecções Oportunistas/economia , Infecções Oportunistas/microbiologia , Infecções Oportunistas/prevenção & controle , Infecções Oportunistas/veterinária , Infecções Estafilocócicas/economia , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/fisiologia , Infecções Estreptocócicas/economia , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/prevenção & controle , Streptococcus agalactiae/fisiologia
7.
Acta Vet Scand ; 61(1): 21, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31023344

RESUMO

The use of pre- and post-milking teat disinfectants can reduce teat bacterial load and aid in the collection of high-quality milk. The objective of this study was to compare the reduction in bacteria populations on teat skin after the application of different commercial teat disinfectant products. Ten teat disinfectant products were applied to the teats of 10 Holstein-Friesian cows. One cow received one teat disinfectant product at each sampling point before cluster application for milking. A composite swab sample was taken of the 4 teats of each cow before and after teat disinfectant application. Swab samples were placed on three different selective agars to enumerate bacterial counts of staphylococcal, streptococcal and coliforms isolates on teat skin. Staphylococcal isolates were the most prominent bacterial group recovered on teat swabs (49%), followed by streptococcal (36%) and coliform (15%) isolates before the application of disinfectant. The average bacterial reductions on teat skin were shown to be 76%, 73% and 60% for staphylococcal, streptococcal and coliform isolates, respectively. All of the teat disinfectant products tested reduced teat bacterial load for all three bacterial groups. Product 4 containing 0.6% w/w diamine was the most effective against bacterial populations of staphylococcal and streptococcal isolates on teat skin with a reduction of 90% and 94%, respectively. Whereas product 10, which contained 0.5% w/w iodine, resulted in the highest reduction in coliforms on teat skin with a reduction of 91%. Results from this study suggest that specific bacterial population loads on teats can be reduced using different teat disinfectant formulations.


Assuntos
Bactérias/efeitos dos fármacos , Desinfetantes/farmacologia , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/prevenção & controle , Pele/microbiologia , Animais , Bactérias/classificação , Bovinos , Desinfetantes/química , Enterobacteriaceae/efeitos dos fármacos , Feminino , Mastite Bovina/microbiologia , Staphylococcus/efeitos dos fármacos , Streptococcus/efeitos dos fármacos
8.
Prev Vet Med ; 167: 53-60, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31027722

RESUMO

The purpose of this study was twofold. First, we developed and validated the domain-specific Mastitis Prevention Self-Efficacy scale (MPSES), derived from developing a corresponding scale for the General Self-Efficacy Scale and consisting of 10 items describing dairy farmers' feelings of confidence about being able to prevent, reduce and control mastitis, a common infection of the udder. Second, farmers' cognitive assessment of mastitis was used in order to explore the correlation of general and domain-specific self-efficacy. The MPSES was completed by a sample of Swedish fulltime dairy farmers (n = 290) through an online questionnaire. The instrument was found to possess good reliability (Cronbach's alpha α = .90) and correlated well with the S-GSE (r.62). Medium effects was identified by a correlation between the MPSES and farmers' cognitive assessment of time-line (r = 0.3, p < 0.001), and small effects for cure/control (r = .12, p < 0.05) as well as for aspects related to cause (r = .17-.28, p < 0.001) of mastitis. The potential usefulness of this scale in the dairy industry is discussed.


Assuntos
Criação de Animais Domésticos/métodos , Fazendeiros , Mastite Bovina/prevenção & controle , Idoso , Animais , Bovinos , Coleta de Dados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
9.
Res Vet Sci ; 124: 186-190, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30909121

RESUMO

A trial was conducted to determine if feeding OmniGen-AF® (OG) to 22 late lactation cows 60 days prior to and during the early dry period, a time of increased susceptibility to mastitis, could reduce disease incidence in a dairy herd experiencing major health issues. Treated cows (n = 11) consumed a ration containing OG [9 g/100 kg of body weight/day] beginning 60 days before dry-off, during the dry period, and through 30 days in milk (DIM). Control cows received the same ration during the dry period through 30 DIM only. Body weights, body condition scores (BCS), intramammary infection (IMI) prevalence, new IMI rates, somatic cell counts (SCC), milk yield, and adverse health events were measured. No differences were found between treatments for body weight or BCS. Adverse health event data at calving showed no differences between treatments except for percentage of cows with hyperketonemia, which was lower among treated cows (63.6% vs 100%). Prevalence of IMI from calving through 30 DIM for treated cows (6.1%) was lower than controls (11.05%); likewise, new IMI rate during this time for treated cows (0.61%) was lower than controls (5.81%). The SCC from calving through 30 DIM for treated cows (215,000/ml) was lower than controls (493,000/ml). Average production/day at the first DHIA test (~33 DIM) showed that treated cows produced more milk (39.9 kg) than controls (35.34 kg). In conclusion, feeding OG 60 days prior to dry-off reduced hyperketonemia and mastitis, lowered SCC, and numerically increased milk yield in a dairy herd experiencing major health issues.


Assuntos
Suplementos Nutricionais/análise , Glândulas Mamárias Animais/imunologia , Mastite Bovina/prevenção & controle , Leite/metabolismo , Ração Animal/análise , Animais , Bovinos , Contagem de Células/veterinária , Dieta/veterinária , Feminino , Georgia/epidemiologia , Mastite Bovina/epidemiologia , Prevalência
10.
Ann Agric Environ Med ; 26(1): 39-45, 2019 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-30922027

RESUMO

INTRODUCTION: Mastitis may result in physical, chemical and microbiological changes in milk and pathological lesions in the glandular tissue. Milk derived from cows with mastitis may become a cause of infections in humansw and animals. OBJECTIVES: The aim of this study was to assess the effectiveness of selected dipping agents in the inactivation of several bacteria that may cause mastitis in cattle. MATERIAL AND METHODS: Three strains of each of the following species: Escherichia coli, Klebsiella pneumoniae, Serratia marcescens, Staphylococcus aureus and Listeria monocytogenes, isolated from milk, were used in the study. Identification of isolates was carried out using the automatic system VITEK2 Compact. Evaluation of the genetic similarity between the tested strains was made using the RAPD technique. Drug susceptibility of strains was evaluated with the disc diffusion method. Assessment of the effectiveness of iodine, stabilized iodine, povidone iodine and chlorhexidine was performed using fragments of skin from cow teats. RESULTS: All the tested strains were genetically different. Most of them were susceptible to the studied antibiotics. Only two strains of L. monocytogenes were resistant to all the studied antibiotics. The percentage rate of reduction in the number of bacteria after using of dipping agents was very high (>90%). The most susceptible to the dipping preparations used were L. monocytogenes (99.6 - 99.9%). Stabilized iodine was the most effective dipping agent for all tested bacteria, causing a reduction rate in the number of bacteria from 99.80% (E. coli) - 99.99% (S. aureus, L. monocytogenes). CONCLUSIONS: The results obtained may contribute to a reduction in udder infections in cows, especially mastitis, and improve the quality of the milk.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/prevenção & controle , Animais , Anti-Infecciosos Locais/farmacologia , Bactérias/genética , Bovinos , Clorexidina/farmacologia , Indústria de Laticínios/métodos , Feminino , Iodo/farmacologia , Mastite Bovina/microbiologia , Povidona-Iodo/farmacologia
11.
Artigo em Alemão | MEDLINE | ID: mdl-30808026

RESUMO

OBJECTIVE: In some cases, classical diagnostic procedures of bovine mastitis, including adspectation, palpation, and examination of milk samples, are of limited reliability, such that histological examination of udder tissue would be a useful addition. The study aimed to identify localizations for tissue sampling and to validate the biopsy technique. ANIMALS AND METHODS: In the present study, sonographic examinations on bovine udders (n = 16) were performed, to identify ideal localizations for tissue sampling, which were tested in slaughterhouse organs (n = 10) and verified in udders of lactating cows (n = 16). RESULTS: Ideal localizations for tissue sampling, avoiding puncturing of blood vessels, were sonographically identified in the area of the udder cistern. Tissue sampling in lactating cows proved to be free of complications in 73 % of cases and all tissue specimens obtained were suitable for histology. CONCLUSION AND CLINICAL RELEVANCE: Tissue sampling by biopsy for microbiological and histopathological examinations supplements common procedures in the diagnostics of mastitis in the dairy cow and, if performed in the area of the udder cistern, can be conducted without sonographical control under field conditions.


Assuntos
Biópsia/veterinária , Indústria de Laticínios/métodos , Glândulas Mamárias Animais/patologia , Mastite Bovina/patologia , Ultrassonografia/veterinária , Animais , Biópsia/efeitos adversos , Biópsia/métodos , Bovinos , Feminino , Lactação , Mastite Bovina/diagnóstico por imagem , Mastite Bovina/prevenção & controle
12.
Anim Sci J ; 90(3): 445-452, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30656804

RESUMO

Microbiota of the gut, milk, and cowshed environment were examined at two dairy farms managed by automatic milking systems (AMS). Feed, rumen fluid, feces, milk, bedding, water, and airborne dust were collected and the microbiota on each was assessed by Illumina MiSeq sequencing. The most abundant taxa in feed, rumen fluid, feces, bedding, and water were Lactobacillaceae, Prevotellaceae, Ruminococcaceae, Ruminococcaceae, and Lactobacillaceae, respectively, at both farms. Aerococcaceae was the most abundant taxon in milk and airborne dust microbiota at farm 1, and Staphylococcaceae and Lactobacillaceae were the most abundant taxa in milk and airborne dust microbiota at farm 2. The three most prevalent taxa (Aerococcaceae, Staphylococcaceae, and Ruminococcaceae at farm 1 and Staphylococcaceae, Lactobacillaceae, and Ruminococcaceae at farm 2) were shared between milk and airborne dust microbiota. Indeed, SourceTracker indicated that milk microbiota was related with airborne dust microbiota. Meanwhile, hierarchical clustering and canonical analysis of principal coordinates demonstrated that the milk microbiota was associated with the bedding microbiota but clearly separated from feed, rumen fluid, feces, and water microbiota. Although our findings were derived from only two case studies, the importance of cowshed management for milk quality control and mastitis prevention was emphasized at farms managed by AMS.


Assuntos
Microbiologia do Ar , Ração Animal/microbiologia , Criação de Animais Domésticos , Bactérias/isolamento & purificação , Bactérias/patogenicidade , Roupas de Cama, Mesa e Banho/microbiologia , Roupas de Cama, Mesa e Banho/veterinária , Extração de Leite/métodos , Bovinos , Indústria de Laticínios/métodos , Poeira , Fazendas , Fezes/microbiologia , Abrigo para Animais , Leite/microbiologia , Rúmen/microbiologia , Microbiologia da Água , Animais , Feminino , Qualidade dos Alimentos , Mastite Bovina/prevenção & controle , Controle de Qualidade
13.
N Z Vet J ; 67(2): 93-100, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30557522

RESUMO

AIMS: To examine the association between the interval from internal teat sealant (ITS) administration to calving and the incidence of farmer-recorded clinical mastitis in the first 30 days of lactation in pasture-based dairy heifers. METHODS: Heifers that were administered an ITS by a single veterinary business in the South Island of New Zealand over the winter of 2014 were enrolled in a cross-sectional observational study. ITS was administered to all heifers on each participating farm on a single calendar day. The dates of calving and farmer-diagnosed clinical mastitis were recorded by farm staff. The interval from ITS administration to calving was categorised into four approximately evenly sized groups: <35, 35-48, 49-69 and >69 days. The quartile of the farm's calving period in which each heifer calved was also investigated as a potential confounding variable. A hierarchical logistic regression model was constructed to determine the association between the interval from ITS administration to calving with the odds of clinical mastitis in the first 30 days of lactation. RESULTS: Analysis was performed on 7,126 eligible heifers from 31 farms, with ITS administered between 9 May and 11 July 2014. The mean interval from ITS administration to calving was 52.9 (SD 24.4, min 1, max 137) days. Clinical mastitis was diagnosed in 420/7,126 (5.9 (95% CI=5.4-6.5)%) heifers between calving and day 30 of lactation. In the final multivariable model, which included calving period quartile, interval from ITS administration to calving was not associated with the odds of clinical mastitis (p=0.516). Compared to an interval from ITS administration to calving of <35 days, the adjusted OR of clinical mastitis for intervals of 35-48, 49-69 and >69 days were 0.83 (95% CI=0.59-1.17), 0.71 (95% CI=0.45-1.11) and 0.68 (95% CI=0.36-1.29), respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Within the range of intervals from ITS administration to calving observed in this study, there was no association with the odds of clinical mastitis in the first 30 days of lactation in dairy heifers. This study suggests that veterinary clinics may be able to extend their ITS administration service and treat dairy heifers earlier than the current recommendation of approximately 4 weeks before the planned start of calving.


Assuntos
Bismuto/farmacologia , Mastite Bovina/prevenção & controle , Animais , Bismuto/administração & dosagem , Bovinos , Estudos Transversais , Feminino , Lactação , Glândulas Mamárias Animais , Mastite Bovina/epidemiologia , Nova Zelândia/epidemiologia , Parto , Período Pós-Parto , Gravidez , Fatores de Tempo
14.
J Dairy Sci ; 102(5): 4727-4740, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30580940

RESUMO

Bovine mastitis affects animal health and welfare and milk production and quality, and it challenges the economic success of dairy farms. Staphylococcus aureus is one of the most commonly found pathogens in clinical mastitis but it also causes subclinical, persistent, and difficult-to-treat intramammary infections. Because of the failure of conventional antibiotic treatments and increasing pressure and concern from experts and consumers over the use of antibiotics in the dairy industry, many attempts have been made over the years to develop a vaccine for the prevention and control of Staph. aureus intramammary infections. Still, no commercially available vaccine formulation demonstrates sufficient protection and cost-effective potential. Multiple factors account for the lack of protection, including inadequate vaccine targets, high diversity among mastitis-provoking strains, cow-to-cow variation in immune response, and a failure to elicit an immune response that is appropriate for protection against a highly complex pathogen. The purpose of this review is to summarize key concepts related to the pathogenesis of Staph. aureus, and its interaction with the host, as well as to describe recent vaccine development strategies for prevention and control of Staph. aureus mastitis.


Assuntos
Antibacterianos/uso terapêutico , Mastite Bovina/prevenção & controle , Infecções Estafilocócicas/veterinária , Vacinas Antiestafilocócicas/imunologia , Staphylococcus aureus/imunologia , Animais , Bovinos , Indústria de Laticínios , Feminino , Interações Hospedeiro-Patógeno , Mastite Bovina/tratamento farmacológico , Mastite Bovina/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/genética , Staphylococcus aureus/patogenicidade
15.
J Dairy Sci ; 102(2): 1428-1442, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30594383

RESUMO

Staphylococcus aureus is a major pathogen causing intramammary infections (IMI) in dairy cattle herds worldwide. Simulation models can be used to investigate the epidemiologic and economic outcomes of different control strategies against IMI. The transmission rate parameter is one of the most influential parameters on the outcomes of these simulation models. Very few studies have estimated the transmission rate parameter and investigated the transmission dynamics of Staph. aureus IMI in dairy cattle herds. The objective of our study was therefore to analyze the transmission dynamics of Staph. aureus in 2 Danish dairy herds participating in a longitudinal study. The 2 herds had 180 and 360 milking cows, and animals were tested at quarter level once per month over a period of 1 yr. We estimated the quarter-level prevalence to be 34% for herd 1 and 2.57% for herd 2. The daily quarter-level transmission rate was estimated to be 0.0132 and 0.0077 cases/quarter-day for herds 1 and 2, respectively, and the median duration of infection was estimated to be 91 and 64 d for herds 1 and 2, respectively. We also estimated the reproductive ratio at 1.21 for herd 1 and 0.52 for herd 2. The results can provide valuable information for simulation models to aid decision-making in terms of the prevention and control of Staph. aureus IMI in dairy cattle herds.


Assuntos
Mastite Bovina/transmissão , Infecções Estafilocócicas/veterinária , Animais , Bovinos , Indústria de Laticínios , Feminino , Estudos Longitudinais , Mastite Bovina/epidemiologia , Mastite Bovina/microbiologia , Mastite Bovina/prevenção & controle , Prevalência , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/prevenção & controle , Infecções Estafilocócicas/transmissão , Staphylococcus aureus
16.
PLoS One ; 13(12): e0209236, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30540846

RESUMO

Parturition is a painful event experienced by cows at the onset of lactation. This pain could lead to a reduced feed intake, altered metabolic and immunological status, and a host of other diseases that could seriously limit her productive herd lifespan. The objective of the current study was to assess the effect of administration of a single dose of oral meloxicam, a non-steroidal anti-inflammatory drug (NSAID), on the production and health status of cows during their lactation. A total of 2,653 (1,009 meloxicam-treated and 1,644 untreated control) cows were enrolled across 20 herds in the provinces of Ontario and Quebec, Canada. Relative to untreated controls, meloxicam-treated cows produced 0.64 kg/day (SE = 0.29. P = 0.03) more milk over the first 3 test days (90-120 days in lactation), had 0.75 times the odds of subclinical mastitis at first test (SE = 0.08, P = 0.01), and were culled or died at 0.46 times the rate (SE = 0.16, P = 0.03) before 60 days in milk. These results are consistent with previous research and lend support to the hypothesis that parturition is a painful event in cattle. Attempts to ameliorate such pain with analgesics is associated with a variety of positive health and production outcomes.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Meloxicam/administração & dosagem , Administração Oral , Criação de Animais Domésticos , Animais , Bovinos , Doenças dos Bovinos/mortalidade , Doenças dos Bovinos/prevenção & controle , Indústria de Laticínios , Feminino , Lactação/efeitos dos fármacos , Mastite Bovina/prevenção & controle , Parto , Distribuição Aleatória , Resultado do Tratamento
17.
Braz. J. Vet. Res. Anim. Sci. (Online) ; 55(3): e137149, Outubro 25, 2018. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-969147

RESUMO

Mastitis affects a high proportion of dairy cows throughout the world and is one of the greater problems faced by the dairy industry today. The disease is still a major cause of economic loss on a dairy farm. Mastitis poses not only negative consequences for the dairy farmer but also for the dairy industry as a number of issues threaten the reputation of milk as a healthy product from healthy animals. The use of antimicrobials is one of those concerns and threats. Antimicrobial usage on dairy farms is most often related to udder health as most medicines are used in prevention and control of mastitis. Antimicrobials remain vital for treatment of bacterial infections in dairy cattle, but in light of the upcoming debate instigated by the potential link between the use of antimicrobial products in animal husbandry and the development of antimicrobial resistance in both animal and human pathogens, there is an urgent need for innovation and alternatives to antibiotic therapy for mastitis treatment and control. Alternative approaches include vaccination, probiotics or beneficial microorganisms and inhibitory substances, immunomodulation, bacteriophages, homeopathy, and plant-derived inhibitory substances, yet only when scientifically-proven evidence is available indicating these alternatives are effective.(AU)


A mastite ocorre em uma alta proporção de vacas leiteiras em todo o mundo e é um dos grandes problemas que atinge a indústria leiteira. A doença ainda é uma das maiores causas de perdas econômicas das granjas leiteiras. A mastite não tem apenas consequências negativas para os fazendeiros, mas atinge também a indústria leiteira, particularmente pela expectativa de que o leite deve ser um produto saudável produzido por animais saudáveis. O uso de antimicrobianos é uma grande preocupação. O emprego de antimicrobianos nas granjas leiteiras está frequentemente relacionado com a saúde do úbere uma vez que a maioria dos medicamentos são usados na prevenção e controle da mastite. Os antimicrobianos ainda são vitais para o tratamento das infecções bacterianas do gado leiteiro, mas na atualidade há um grande questionamento para a ligação potencial entre o uso de produtos antimicrobianos no manejo animal e o desenvolvimento de resistência antimicrobiana tanto de patógenos de animais como de humanos, há portanto a necessidade urgente da introdução de alternativas para o tratamento e controle da mastite com antibióticos. As possibilidades incluem vacinação, probióticos ou microorganismos benéficos e substâncias inibidoras, imunomodulação, bacteriófagos, homeopatia, fitoterápicos inibidores. Contudo todos esses procedimentos necessitam ser cientificamente provadas para demonstrar que são alternativas realmente efetivos. (AU)


Assuntos
Animais , Feminino , Bovinos , Mastite Bovina/prevenção & controle , Bovinos/anormalidades , Vacinação/veterinária
18.
Vet Res Commun ; 42(3): 243-250, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30043292

RESUMO

Staphylococcus aureus is an opportunistic pathogen that may cause severe infections in livestock, and represents the major cause of mastitis in dairy cows. Currently, instead of using antibiotics, new strategies are sought to reduce this clinical health problem. The aim of this study was to determine the efficacy of phage therapy to kill S. aureus strains obtained from farms located at the State of Guanajuato, México. Thirty-six S. aureus strains from cow milk with subclinical mastitis were isolated and identified, and the susceptibility to antibiotics and four phages also isolated in this work was tested. It was found that more of 90% of S. aureus isolates were not susceptible to six or more antibiotics, and 100% were resistant to penicillin, dicloxacillin, cefotaxime, ampicillin and cephalothin, and 81 and 77%, to tetracycline and cefuroxime, respectively. Fortunately, 100% of S. aureus isolates were susceptible to phages used in this work, which was detected as clear zones using specific phage. It was shown for the first time, that phages used in this study are active against pathogenic S. aureus and might be incorporated into the therapy as an important tool for the control of staphylococcal bovine mastitis, specially to antibiotic-resistant S. aureus strains isolated in farm located at the state of Guanajuato, México; and its use might be extended to other regions inside or outside the country.


Assuntos
Antibacterianos/farmacologia , Bacteriófagos/fisiologia , Farmacorresistência Bacteriana , Mastite Bovina/prevenção & controle , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/virologia , Animais , Bovinos , Feminino , Técnicas In Vitro , México , Infecções Estafilocócicas/prevenção & controle
19.
Microb Pathog ; 122: 63-72, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29885364

RESUMO

Panax ginseng extract (PGe) has been shown to possess immunomodulatory effects in healthy dairy cows at drying off and to trigger an adequate immune response to protect from an experimental intramammary infection (IMI) with Staphylococcus aureus in a murine model. S. aureus is one of the major pathogens isolated from bovine IMI; being capable to invade and survive within mammary epithelial cells. However, the precise mechanism by which PGe interacts with bovine mammary epithelial cells (MAC-T) and bovine macrophages in the course of a S. aureus infection remains unclear. We evaluated the effect of PGe on MAC-T cytokine response and on the internalization of S. aureus into MAC-T. In addition, we evaluated the effect of PGe on the phagocytic activity of macrophages isolated from bovine mammary secretions. Results shown that MAC-T cells TLR4 and NF-κB mRNA expression was not affected by PGe at all evaluated times. IL-6 mRNA expression and protein level and IL-4 protein level were significantly induced in MAC-T treated with 3 mg/ml of PGe. PGe at 3 mg/ml reduced significantly the internalization of two S. aureus strains in MAC-T. In addition, PGe did not affect the percentage of phagocytosis and the NO and ROS production of macrophages co-cultured with two strains of S. aureus. These results, obtained in in vitro models together with those obtained in in vivo previous studies carried out in bovines and mice can contribute to improve the understanding of the effects of PGe following inoculation in bovine mammary glands.


Assuntos
Endocitose/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Mastite Bovina/prevenção & controle , Panax/química , Extratos Vegetais/farmacologia , Staphylococcus aureus/imunologia , Animais , Bovinos , Células Cultivadas , Citocinas/metabolismo , Células Epiteliais/microbiologia , Fatores Imunológicos/isolamento & purificação , Macrófagos/efeitos dos fármacos , Mastite Bovina/microbiologia , Modelos Biológicos , Extratos Vegetais/isolamento & purificação
20.
J S Afr Vet Assoc ; 89(0): e1-e8, 2018 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-29781674

RESUMO

Antibiotic resistance of strains of Staphylococcus aureus isolated from bovine milk is of concern internationally. The objective of this study was to investigate trends of resistance of S. aureus to antibiotics administered to dairy cows in 19 South African and one Zambian dairy herds (participating in the South African proactive udder health management programme) and to identify possible contributing factors. The resistance of S. aureus strains to eight commonly used antibiotics in South Africa from 2001 to 2010 was evaluated. Staphylococcus aureus isolates (n = 2532) were selected from cows with subclinical mastitis in 20 herds routinely sampled as part of the proactive udder health management programme. The isolates were selected from milk samples that had somatic cell counts more than 400 000 cells/mL and were tested for antibiotic resistance using a standard Kirby-Bauer test with published clinical breakpoints. The prevalence of antibiotic resistance was evaluated as a percentage of S. aureus isolates susceptible out of the total numbers for each antibiotic selected per year. Staphylococcus aureus showed a significant increase in percentage of susceptible isolates over time for all antibiotics tested except for ampicillin. The overall prevalence of mastitis did not change during the study period. However, the prevalence of mastitis caused by S. aureus (mostly subclinical cases) in the selected herds decreased numerically but not significantly. Reduction in the incidence of antibiotic resistance shown by S. aureus was presumed to be a result of the application of the proactive udder health management programme. The fact that the overall prevalence of mastitis was kept stable was possibly because of the influence of the management programme in conjunction with the return of infections caused by non-resistant strains.


Assuntos
Farmacorresistência Bacteriana Múltipla , Mastite Bovina , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/efeitos dos fármacos , Criação de Animais Domésticos/métodos , Animais , Antibacterianos/farmacologia , Bovinos , Controle de Doenças Transmissíveis/métodos , Indústria de Laticínios , Feminino , Mastite Bovina/tratamento farmacológico , Mastite Bovina/epidemiologia , Mastite Bovina/microbiologia , Mastite Bovina/prevenção & controle , Leite/microbiologia , Análise de Regressão , África do Sul/epidemiologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/isolamento & purificação , Zâmbia/epidemiologia
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