Severity of experimental escherichia-coli mastitis in ketonemic and nonketonemic dairy-cows.

The severity of experimental Escherichia coli mastitis in relation to in vitro chemotaxis of polymorphonuclear leukocytes was investigated in cows during negative energy balance. The negative energy balance was induced by feed restriction. Cows were classified into two groups, ketonemic and nonketonemic, based on the beta-hydroxybutyrate concentration in the peripheral blood at the moment of inoculation. Bacterial growth in the inoculated quarter was used as a parameter to indicate the severity of experimental mastitis. In the nonketonemic cows, experimental mastitis ranged from moderate to severe. Severity of experimental mastitis was negatively related to preinfection chemotactic response of polymorphonuclear leukocytes. In contrast, the course of experimental mastitis in the ketonemic group was relatively severe in all cows, regardless of preinfection chemotactic response

Genetic correlations among somatic cell scores, productive life, and type traits from the United States and udder health measures from Denmark and Sweden

Sire genetic evaluations for protein yield, somatic cell score (SCS), productive life, and udder type traits from the US were correlated with sire evaluations for udder health from Denmark and Sweden and then the correlations were adjusted for accuracies to approximate genetic correlations. Traits from Denmark and Sweden included somatic cell count (SCC) and clinical mastitis from single-trait analyses. In addition, evaluations for clinical mastitis from Denmark and Sweden were regressed on US traits to test for quadratic relationships. Information from 85 bulls with US and Danish evaluations (77 with US type) and from 80 bulls with US and Swedish evaluations (79 with US type) was used to calculate correlations. Genetic correlations of US protein yield with Danish and Swedish SCC and clinical mastitis were all unfavorable (-0.09 to -0.32). Genetic correlations of US productive life with Danish and Swedish SCC and clinical mastitis were all favorable (0.06 to 0.59). Genetic correlations between US SCS and Danish SCC and between US SCS and Swedish SCC were -0.87 and -0.99, respectively (favorable). Genetic correlations between US SCS and Danish clinical mastitis and between US SCS and Swedish clinical mastitis were -0.66 and -0.49, respectively (favorable). The US type traits that had the largest correlations with clinical mastitis from Denmark and Sweden, respectively, were udder composite (0.26, 0.47), udder depth (0.45, 0.52), and fore udder attachment (0.31, 0.34). In general, quadratic regressions indicated little nonlinearity between clinical mastitis and the US traits. Specifically, the US bulls with the lowest predicted transmitting abilities for SCS had the most favorable rates of daughter clinical mastitis in Denmark and Sweden. Selection for increased productive life, lower SCS, and more shallow udders should improve mastitis resistance.</p

Molecular Genetic Typing of Staphylococcus aureus from Cows, Goats, Sheep, Rabbits and Chickens

End of project reportsS. aureus can also cause a number of infections in animals such as tick-associated pyaemia in lambs, staphylococcosis in rabbits, septicaemia, abscesses and chondronecrosis in chickens and pneumonia and osteomyelitis complex in turkeys. S. aureus is the most frequent cause of bovine mastitis, a disease that is of economic importance worldwide (Beck et al., 1992). Typically staphylococcal mastitis is chronic in nature, with subclinical mastitis being the most common form

The epidemiology of mastitis in Australian dairy cattle : a dissertation submitted in partial fulfilment of the requirements for the degree of Masters of Veterinary Studies (Epidemiology)

This study represents an aggregation of knowledge on mastitis within the Australian dairy industry. Aspects of the epidemiology and economics of mastitis have been collated and areas of missing knowledge identified. A clinical treatment trial was conducted on subclinical mastitis to identify the role of therapy upon subclinical infection. The effect of individual variables on mastitis risk was studied and aggregated in order to facilitate the development of a computer simulation model of mastitis within Australian dairy herds. A literature review of mastitis within the Australian dairy industry was conducted. The economic impact of mastitis was examined and the pathway of economic loss to the dairy industry is discussed. The epidemiology of mastitis was studied with special emphasis on quantification of the effect of individual risk factors on the occurrence of disease. Performance parameters for the current diagnostic tests applied within the dairy industry are presented and their suitability for use in a commercial environment discussed. The impact of self-cure and the efficacy of therapeutic intervention in the disease are examined. The role of culling is presented. The chapter concludes with an estimation of die total economic losses experienced on a commercial dairy farm in Victoria in 1998 for three different mastitis levels. The economic benefit to be gained from a reduction in mastitis is also presented. A clinical treatment trial of subclinically infected cows (high somatic cell count) was conducted in order to determine if therapeutic intervention was an effective management tool. Cows with somatic cell counts in excess of 500,000 cells per ml and more than 14 days calved were selected and randomly assigned to treatment and control groups. A pooled quarter milk sample was taken prior to treatment and repeated at around six weeks after treatment. Treated cows received a course of intramammary and parenteral antibiotics and control cows were untreated. Cows were followed for the rest of the lactation of treatment and into the subsequent lactation and somatic cell counts were recorded. The major pathogens identified were S anreus and S uberis. Treatment did not have a significant or commercially useful effect upon bacteriological cure rates, survival of cows to the next lactation or somatic cell count for the remainder of the lactation. Treatment of high somatic cell count cows during lactation is not recommended and is discussed. A requirement exists for the development of a stochastic simulation model of mastitis within Australian dairy herds. The structure of such a model was developed and is presented. Underlying production and somatic cell count responses in Australian cattle were derived. Infection status variables were included and stochasticity was introduced through the use of control variates. State transition probabilities were collected from the literature. Deficiencies in knowledge were identified and methods for modeling these deficient areas discussed. The aggregated information is presented. It is expected that a working stochastic simulation model of mastitis within Australian dairy herds will be developed from infomation collected in this dissertation

The use of homeopathic nosodes in the prevention of mastitis in organic dairy herds (OF0186)

Mastitis is the most significant disease affecting the health, welfare and economic productivity of dairy cattle and is recognised by Defra as a major economic and welfare concern. Research into the efficacy of homeopathic treatments and of management control of mastitis on organic dairy farms have both been identified as research priorities in recent Defra funded reviews of organic dairy farming. This study examined the use of a specific mode of homeopathic treatment in the prevention of mastitis and quantified the effect that the year-round, prophylactic use of nosodes, supplied to the cattle in the drinking water, had on the number of clinical cases of mastitis on somatic cell counts within herds. Context and background Organic dairy farming is a significant industry with milk being the largest single organic product in the UK. Organic milk is produced to defined standards which meet the Advisory Committee on Organic Standards (ACOS) criteria. These standards ‘emphasise animal welfare and, by avoiding artificial fertilisers, pesticides and other non-natural chemicals, and prohibiting the routine use of antibiotics and other conventional drugs, also ensure care for the environment, and promote the highest standards of food quality and safety’ (Omsco 2005). As part of the management of organic dairy cattle with reduced use of conventional pharmaceutical treatments, many organic farmers use homeopathic and other complementary therapies on their animals. Mastitis is recognised as the main animal health problem in organic milk production systems (Bennedsgaard et al 2003). Whilst mastitis levels appear to be similar to those found in conventional production (Hovi and Roderick, 2000) specific problem areas in mastitis control under organic management standards have been identified. One of the overall goals of organic animal husbandry is to avoid disease through management, husbandry, breeding and feeding. According to the EC-Regulation No. 1804/1999 governing organic livestock production, animal health management should be based on disease prevention. However, the preventive use of chemically synthesised allopathic medicinal products like dry cow antibiotics is not permitted. In organic units, phytotherapeutic and homeopathic products and trace elements are to be used in preference to antibiotic and prolonged withdrawal periods need to be observed after conventional medicine use. As a consequence of these requirements, organic dairy farmers look for alternatives to conventional therapy and prophylaxis (Hektoen 2004). Homeopathy is widely used for the treatment of mastitis within UK organic dairy herds and prophylactic use of homeopathic nosodes, either continuously or just during housing, is practised on many organic dairy farms and is thought to offer general protection against mastitis and to reduce somatic cell counts (SCC). Research into the effectiveness of homeopathic treatments was one of the most important research requirements identified in a recent MAFF review of animal health within organic herds ( Hovi & Roderick 1999). The range of homeopathic treatments used on farm today is wide, with treatment practices either focussing on the needs of the individual animal, which is known as constitutional treatment and which employs individual remedies, or aimed at groups of animals using specific remedies, or ‘nosodes’, which are considered to be a very specific form of homeopathy - isopathy (iso - all the same, pathy – treatment/exposure). Unlike specific remedies, nosodes do not account for the individual needs of each animal, but create the potential for protective treatment for a herd or group, they are generally applied in drinking water, and may be used on individual animals, usually by vulval spray. Benefit for the sector and for Defra Mastitis is the most significant disease affecting the health, welfare and economic productivity of dairy cattle, and management and control of mastitis is an important facet of practical dairy herd management. Mastitis is recognised by Defra as a major economic and welfare problem in dairy cattle. Research into the efficacy of homeopathic treatments and of management control of mastitis on organic dairy farms have both been identified as research priorities in recent Defra funded reviews of organic dairy farming. The Study Ninety-six farms participated in a double-blind trial to compare a homeopathic nosode and an inactive control treatment (carrier alone). Treatments were at the farm level and took place over a period of 12 months or 24 months (some farms were swapped to the opposite treatment during a second year). The treatments were randomised to each farm by a third party. During the trial, where available, records were collected of farm monthly bulk tank somatic cell count (BMSSC), a monthly cell count based on National Milk Recording data (NMR) and the annual number of cases of mastitis as recorded by the farmer. Additional farm level data were collected and their relationship to the level of mastitis on the farms investigated. Objectives of the Study The study described in this report explores the use of a specific mode of homeopathic treatment, a nosode, in the prevention of mastitis and quantifies the effect that the year-round, prophylactic use of nosodes, supplied to the cattle in the drinking water, had in reducing the number of clinical cases of mastitis and also quantifying any effect that the use of a nosode has on somatic cell counts within herds. • To quantify the effectiveness of the prophylactic use of homeopathic nosodes for the treatment of mastitis in reducing the incidence of clinical mastitis and the concentration of somatic cells in milk. • To survey management practices on organically managed farms. • To investigate associations between the homeopathic treatment, farm management practice and the incidence of different types of mastitis and to provide guidance for mastitis control in organic dairy herds. Materials and methods In testing the efficacy of a homeopathic nosode it was determined that the study should: • Look at a nosode already being commonly used and commercially available. • Not ask for new recording systems to be used for data collection but to use the existing systems which are in place. • Not interfere in the ‘normal’ practises carried out by the farms, by, for example, repeated prompting of farmers to carry out treatments, or ask them to adopt prescribed ways for describing, recording or treating mastitis. There are three commonly used measures of the udder health of milking cows: a) The bulk tank milk somatic cell count (BMSCC, commonly referred to as SCC) gives a count (in 000’s cells / ml) of white cells and desquamated cells shed by the udder. The BMSCC is not an accurate indicator for the presence of clinical mastitis, but may give information on sub-clinical (undetected) mastitis. b) Somatic cell counts for individual cows from farms which subscribe to commercial milk recording services (ICSCC). c) The number of cases of mastitis. The incidence rate for clinical mastitis (IRCM) is the number of distinct cases of mastitis in 100 cows in a year. The response variables that were measured were: • Farmers’ own record of mastitis cases. • Bulk milk SCC. • Individual cow somatic cell records (ICSCC) if the farms were on a milk recording service. • Farmer’s opinion of his/her success in controlling mastitis. • A large number of variables, recorded using a questionnaire at the farm visits, which could influence mastitis and the effectiveness of the treatment. After visiting a number of homeopathic pharmacies, an agreement was made with Crossgates homeopathic pharmacy1, and Freemans Homeopathic Pharmacy2 (Appendix D) to make the individual herd specific nosode remedies for the farms. The trial was double-blinded, with blinding carried out by the creation of a randomly generated list of A and B’s. As each new farm was recruited, it was allocated to the next A or B in the sequence, the farms being allocated to either nosode treatment or control, one by one, in chronological order. Articles were written in the organic press, Organic Farming, and The Turning Worm, inviting farms to take part in the study. It was clear that farms should only join the study voluntarily and would not be ‘cold called’ or pressurised to join. One hundred and four farms responded to the call, and 96 of these farms went on to take part in the study. The 8 farms which declined to take part either went out of milk production before the study started, or changed their minds about inclusion in the trial before the start of the study. The 96 farms were visited and the study introduced. Farmers were issued with a kit to collect milk from high cell count cows for preparation as a nosode. An 80 part questionnaire (Appendix A) was used to gather the information needed to understand the possible factors that may influence mastitis. During visits the farmers were also asked whether they were willing to fill in a self assessment of their personality type. Number of farms recruited = 96 Total farms completing the study period = 88 Number of farm years followed = 206 Average herd size = 101 cows Number of cows followed in the study = 9,680 Number of cows receiving remedy (R) = 4,734 Number of cows receiving control (P) = 4,946 Total cow years followed = 21,580 cow years (Some farms two years, some 3 years) Farms lost during study = 8 (due to sale of the herd, or going out of milk production and into, for example, heifer rearing) Results The data collected were subject to a number of different analyses:- 1. A test for an effect of the homeopathic nosode in reducing the cell count in milk. 2. A test for an effect of the homeopathic nosode in reducing the annual cases of mastitis. 3. An analysis to identify risk factors associated with increased cell count in milk. 4. An analysis to identify risk factors associated with higher levels of mastitis. No effect of nosode in reducing either the incidence of cases of mastitis or the somatic cell counts in the milk were detected. The following risk factors were found to be associated with composite cell counts:- • A decrease in cell count with increased culling of high cell count cows • A decrease in cell count for farms which use complementary therapies on dry cows • A decrease in cell count for farms which use dry cow therapy, including teat sealants, on dry cows • An increased cell count for farms which did not pre-wipe before milking or pre-wiped the teats with a cloth before milking • An increase in cell count for farms which pre-wipe only the udders of cows which are visibly dirty before milking The following risk factors were found to be associated with the number of cases of mastitis:- • Increasing herd yield is associated with increased mastitis case numbers • Increased calving of cows indoors in a calving box was associated with increased numbers of mastitis cases • Use of an in line clot filer was associated with reduced numbers of mastitis cases • Having an abreast parlour (as opposed to a herringbone or rotary parlour) was associated with a reduced numbers of mastitis cases The extent to which the objectives set have been achieved The effectiveness of homeopathic nosodes in treating mastitis and lowering cell count is quantified and described (Objective 1) and the survey results of management practices on organically managed dairy farms are described (Objective 2). Additionally, the associations between homeopathic treatment, farm management practices, mastitis incidence and cell count are quantified (Objective 4) and management controls which show a reduction in mastitis cases or cell counts are identified as risk factors and described in the report (Objective 5). Conclusions • There was no significant effect of the herd specific nosode on either the cell count of milk or the number of cases of mastitis. • That there were strong ‘within farm’ correlations of cell count and cases i.e. between farms, farms tend to stay at the same level of cases and average cell count from year to year. • That there was a characteristic pattern of seasonal change in cell counts (this is already widely recognised). • The study provides useful and interesting statistics on organic dairy farm production. • The study identified an association between decreased cell count and culling for high cell count, the use of complementary dry cow therapy and the use of traditional dry cow therapy. • The study identified an association between increased cell count and not pre-wiping the udder, pre-wiping using a cloth and only pre-wiping dirty cows. • The study identified an association between higher numbers of mastitis cases and higher average yield and also with higher percentage of cows calving in a calving box. • An association was identified between decreased numbers of mastitis cases and the use of an in-line clot filter and also with farms with an abreast parlour (rather than a herring-bone parlour). • Eighty five per cent of farmers in the survey responded that they did believe in non-conventional remedies, and 62 per cent of farmers responded that they used non-conventional remedies on their own family

Variation of inflammatory dynamics and mediators in primiparous cows after intramammary challenge with Escherichia coli

The objective of the current study was to investigate (i) the outcome of experimentally induced Escherichia coli mastitis in primiparous cows during early lactation in relation with production of eicosanoids and inflammatory indicators, and (ii) the validity of thermography to evaluate temperature changes on udder skin surface after experimentally induced E. coli mastitis. Nine primiparous Holstein Friesian cows were inoculated 24 +/- 6 days (d) after parturition in both left quarters with E. coli P4 serotype O32:H37. Blood and milk samples were collected before and after challenge with E. coli. The infrared images were taken from the caudal view of the udder following challenge with E. coli. No relationship was detected between severity of mastitis and changes of thromboxane B2 (TXB2), leukotriene B4 (LTB4) and lipoxin A4 (LXA4). However, prostaglandin E2 (PGE2) was related to systemic disease severity during E. coli mastitis. Moreover, reduced somatic cell count (SCC), fewer circulating basophils, increased concentration of tumor necrosis factor-alpha (TNF-alpha) and higher milk sodium and lower milk potassium concentrations were related to systemic disease severity. The thermal camera was capable of detecting 2-3 degrees C temperature changes on udder skin surface of cows inoculated with E. coli. Peak of udder skin temperature occurred after peak of rectal temperature and appearance of local signs of induced E. coli mastitis. Although infrared thermography was a successful method for detecting the changes in udder skin surface temperature following intramammary challenge with E. coli, it did not show to be a promising tool for early detection of mastitis

Potential mechanism of action of J5 vaccine in protection against severe bovine coliform mastitis.

Coliform mastitis is one of the most difficult diseases to treat in the modern dairy industry. Curative therapy with antibiotics remains only moderately effective and depends on the stage at which the disease is treated, The most successful strategies for combating coliform. mastitis appear to be prevention by hygienic management or prophylactic immunization. The severity of clinical symptoms of coliform mastitis has been shown to be reduced by immunization with the Escherichia coli J5 vaccine. However, although the J5 vaccine has been licensed in the United States for about 10 years, the immunological basis of its mechanism of action is still unknown. Until now, protection by J5 vaccination has often been explained by a straight forward mechanism of enhanced antibody production resulting in increased opsonization of coliform bacteria and lipopolysaccharides (LPS). The possibility that J5 vaccination could decrease risk factors for coliform mastitis such as impaired blood polymorphonuclcar neutrophil leukocyte (PMN) diapedesis has never been investigated. This review provides arguments to support the hypothesis that J5 vaccination may reduce the severity of coliform mastitis by inducing a condition of mammary gland hyper-responsiveness, characterized by a T helper 1 (Th1) response and mediated by memory cells inside the mammary gland, finally resulting in enhanced PMN diapedesis upon an intramammary infection

L-selectin and beta(2)-integrin expression on circulating bovine polymorphonuclear leukocytes during endotoxin mastitis

The aim of this in vivo study was to examine the effect of intramammarily administered endotoxin (lipopolysaccharide, LPS) on the expression of L-selectin (CD62L) and the beta(2)-integrin subunits CD11b and CD18 on circulating bovine PMN. Six early lactating cows were infused with Escherichia coli LPS. The adhesion molecules under study were stained at the cell surface and analyzed flow cytometrically. In addition, some of the clinical parameters associated with adhesion molecule mobilization such as fever, blood cortisol levels, somatic cell count (SCC), and total and differential blood leukocyte count were measured. In analogy with observations during clinical coliform mastitis, a progressive decrease of CD62L expression levels was observed early after LPS infusion, concomitantly with a continuous rise of CD11b and CD18 density. However, no correlation was found between the kinetics of CD11b and CD18 density. The initial changes in adhesion molecule expression paralleled the decrease in blood PMN numbers, together with the increase in rectal temperature, cortisol levels, SCC, and number of circulating immature PMN. In conclusion, intramammarily administered LPS seems to play an important role in modulating adhesion receptor expression on circulating bovine PMN. Interestingly, in contrast to coliform mastitis, the net CD18 variation is not principally influenced by CD11b upregulation during endotoxin administration. The knowledge of adhesion molecule kinetics in relation to the different parameters evaluated in the present study contributes to an improved understanding of the inflammatory reaction