Initial assessment of the economic burden of major parasitic helminth infections to the ruminant livestock industry in Europe

We report a European wide assessment of the economic burden of gastrointestinal nematodes, Fasciola hepatica (common liver fluke) and Dictyocaulus viviparus (bovine lungworm) infections to the ruminant livestock industry. The economic impact of these parasitic helminth infections was estimated by a deterministic spreadsheet model as a function of the proportion of the ruminant population exposed to grazing, the infection frequency and intensity, the effect of the infection on animal productivity and mortality and anthelmintic treatment costs. In addition, we estimated the costs of anthelmintic resistant nematode infections and collected information on public research budgets addressing helminth infections in ruminant livestock. The epidemiologic and economic input data were collected from international databases and via expert opinion of the Working Group members of the European Co-operation in Science and Technology (COST) action COMbatting Anthelmintic Resistance in ruminants (COMBAR). In order to reflect the effects of uncertainty in the input data, low and high cost estimates were obtained by varying uncertain input data arbitrarily in both directions by 20 %. The combined annual cost [low estimate-high estimate] of the three helminth infections in 18 participating countries was estimated at € 1.8 billion [€ 1.0-2.7 billion]. Eighty-one percent of this cost was due to lost production and 19 % was attributed to treatment costs. The cost of gastrointestinal nematode infections with resistance against macrocyclic lactones was estimated to be € 38 million [€ 11-87 million] annually. The annual estimated costs of helminth infections per sector were € 941 million [€ 488 - 1442 million] in dairy cattle, € 423 million [€ 205-663 million] in beef cattle, € 151million [€ 90-213 million] in dairy sheep, € 206 million [€ 132-248 million] in meat sheep and € 86 million [€ 67-107 million] in dairy goats. Important data gaps were present in all phases of the calculations which lead to large uncertainties around the estimates. Accessibility of more granular animal population datasets at EU level, deeper knowledge of the effects of infection on production, levels of infection and livestock grazing exposure across Europe would make the largest contribution to improved burden assessments. The known current public investment in research on helminth control was 0.15 % of the estimated annual costs for the considered parasitic diseases. Our data suggest that the costs of enzootic helminth infections which usually occur at high prevalence annually in ruminants, are similar or higher than reported costs of epizootic diseases. Our data can support decision making in research and policy to mitigate the negative impacts of helminth infections and anthelmintic resistance in Europe, and provide a baseline against which to measure future changes.

THE FATE OF THE GIANT CELLS WHICH FORM IN THE ABSORPTION OF COAGULATED BLOOD SERUM IN THE ANTERIOR CHAMBER OF THE RABBIT'S EYE

The conclusion seems warranted that the giant cells formed in the absorption of coagulated blood serum inserted into the anterior chamber of the rabbit's eye subdivide again into uninuclear small cells that take part with other new-formed cells derived from the lining of this space to form a densely fibrillated mass of tissue that resembles quite closely the cornea in its structure. This demonstration materially strengthens the opinion expressed by the writer in his previous article in this Journal,* that the giant cells in healing non-degenerated tuberculous tissue may separate into small living cells, and that the giant cells of tuberculosis are not necrobiotic elements from the very moment and from the very mode of their formation, as has been the general teaching, especially in Germany.

THE VASCULAR CHANGES OF TUBERCULOUS MENINGITIS, ESPECIALLY THE TUBERCULOUS ENDARTERITIES

1. In tuberculosis meningitis there is a tuberculosis endarteritis characterized by the formation of intimal tubercles and a diffuse subendothelial, intimal proliferation due to implantation of tubercle bacili from the blood. From the endarteritis the infiltration may spread into the muscular coat and the adventitia, and the whole wall may undergo caseous and hyaline degeneration. 2. Tuberculous proliferation in the adventitia may invade the media and the intima, and the whole wall of the arterial segment may undergo degeneration. 3. The veins are constantly the seat of more or less extensive infiltration, which always results from adjacent extravascular or arterial foci. 4. The epithelioid cells of the subendothelial, tuberculous intimal See PDF for Structure proliferation are most likely derived from the subendothelial layer of connective tissue and not from the endothelial lining.

Review of the current involvement of homeopathy in veterinary practice and research

Homeopathy has become the focus of increasing interest and use as a complementary and alternative treatment for both human and animal disease. However, from the point of view of academic medicine, this type of therapy is controversial. The use of highly diluted remedies cannot be reconciled with the scientific theories on which the current understanding of disease and its treatment is based, and clinical research in the field is considered to be neither extensive enough nor of a high enough standard to determine whether homeopathic treatments are clinically effective. Animals have no choice in their treatment and are dependent on the judgements of their owners and their therapists. There is therefore a need for information about the effects and consequences of the use of alternative therapies. This paper discusses the use of homeopathy in the treatment of animal disease from the point of view of academic veterinary medicine, and the various approaches to research in this field, with an emphasis on the randomised clinical trial. It also discusses the role of the placebo response and the natural resolution of disease in the clinical evaluation of homeopathic treatment.

Comparison of homeopathy, placebo and antibiotic treatment of clinical mastitis in dairy cows - methodological issues and results from a randomized-clinical trial

Based on the widespread use of homeopathy in treatment of animal disease and the poor documentation of its possible effects and consequences, a clinical trial was carried out in order to evaluate the efficacy of homeopathy in treatment of clinical mastitis in dairy cows and a design for clinical studies on homeopathic treatment, taking into account the guidelines for randomized-clinical trials (RCT) as well as the basic principles of homeopathy. A three-armed, stratified, semi-crossover design comparing homeopathy, placebo and a standardized antibiotic treatment was used. Fifty-seven dairy cows were included. Evaluation was made by two score scales, with score I measuring acute symptoms and score II measuring chronic symptoms, and by recording the frequencies of responders to treatment based on four different responder definitions. Significant reductions in mastitis signs were observed in all treatment groups. Homeopathic treatment was not statistically different from either placebo or antibiotic treatment at day 7 (P = 0.56, P = 0.09) or at day 28 (P = 0.07, P = 0.35). The antibiotic treatment was significantly better than placebo measured by the reduction in score I (P < 0.01). Two-thirds of the cases both in the homeopathy and placebo groups responded clinically within 7 days. The outcome measured by frequencies of responders at day 28 was poor in all treatment groups. Evidence of efficacy of homeopathic treatment beyond placebo was not found in this study, but the design can be useful in subsequent larger trials on individualized homeopathic treatment.

Investigations of the motivation underlying Norwegian dairy farmers' use of homoeopathy

Eighteen Norwegian dairy farmers were interviewed to examine their reasons for using homoeopathic treatments in managing their herds' health. Overall, they chose the treatments on the basis of factors related to their personal experience, considerations of individual animals and the framework for dairy production. For individual animals homoeopathy was used as an alternative to conventional veterinary treatment, but at the herd level it was used to complement it. The farmers' use of homoeopathic treatment for personal health problems and the experience of their colleagues with its use in dairy production were important factors motivating their initial use of homoeopathy. Other factors included a desire to decrease the use of antibacterial drugs, reduce costs and find alternatives when conventional veterinary medicine provided no effective treatment. In individual cases, the severity of disease, previous experience and the farmers' personal knowledge and resources were important. These factors parallel those found to influence the use of complementary and alternative therapies in human medicine. The lack of understanding and documentation of the effects of homoeopathic remedies was not important to the farmers, and they valued personal experience more highly than scientific evidence or the opposition to homoeopathy encountered within the veterinary profession.

Evaluation of Stratification Factors and Score-scales in Clinical Trials of Treatment of Clinical Mastitis in Dairy Cows

There is often a need to reduce sample size in clinical trials due to practical limitations and ethical considerations. Better comparability between treatment groups by use of stratification in the design, and use of continuous outcome variables in the evaluation of treatment results, are two methods that can be used in order to achieve this. In this paper the choice of stratification factors in trials of clinical mastitis in dairy cows is investigated, and two score-scales for evaluation of clinical mastitis are introduced. The outcome in 57 dairy cows suffering from clinical mastitis and included in a clinical trial comparing homeopathic treatment, placebo and a standard antibiotic treatment is investigated. The strata of various stratification factors are compared across treatments to determine which other factors influence outcome. The two score scales, measuring acute and chronic mastitis symptoms, respectively, are evaluated on their ability to differentiate between patients classified from clinical criteria as responders or non-responders to treatment. Differences were found between the strata of the factors severity of mastitis, lactation number, previous mastitis this lactation and bacteriological findings. These factors influence outcome of treatment and appear relevant as stratification factors in mastitis trials. Both score scales differentiated between responders and non-responders to treatment and were found useful for evaluation of mastitis and mastitis treatment.

RENEWAL OF MULTIPLE PRECIPITIN PRODUCTION ON INJECTION OF ONE ANTIGEN IN RABBITS SUCCESSIVELY IMMUNIZED WITH MANY ANTIGENS

Multiple precipitin formation may be induced in the rabbit by the successive introduction of different antigens, and many precipitins may exist simultaneously in the blood for some time. Precipitins no longer demonstrable in the blood of a rabbit subjected to multiple successive immunization may reappear on the injection of only one of the antigens previously injected. Whether an unused antigen would have the same effect has not been determined.