Warble fly infestation and climate.
Explore the source record for details and available documents.
SEARCH · PubMed Health
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
A nationwide survey was conducted of the relative distribution and life cycles of the two cattle warble fly species Hypoderma bovis and H lineatum to complement information derived from examining livestock at markets and hide damage at slaughter. Warble fly larvae were collected from cattle at abattoirs in 59 counties in England, Wales and Scotland from February 1 to June 30, 1979. H bovis was commonest in all areas except the Western isles of Scotland. There was no evidence of cross-infestation between cow and deer warble species.
A survey of warble-infested 'fat' cattle in 57 selected livestock markets in Great Britain was carried out during June 1972 and during May each year from 1973 to 1984. The annual total number of cattle inspected varied from 41,587 to 60,481. The level of infestation increased from 22.3 per cent in 1972 to 38.0 per cent in 1976 and then declined slightly to 34.3 per cent in 1978. Following the introduction of legislation and the warble fly eradication campaign in 1978 there was a rapid decrease to 8.6 per cent infestation by 1979 and by 1984 the level was less than 0.02 per cent.
The costs of warble fly in cattle have been estimated at 35 million pounds for Great Britain in 1985 and $85 million for Italy in 1982. Control measures within the European Community vary from one country to another and from the voluntary application of systemic products by individual farmers to comprehensive national eradication schemes backed by legislation. Of the countries opting for national eradication measures, Denmark has been successful and the Federal Republic of Germany, the Netherlands, the Republic of Ireland, Northern Ireland and Great Britain have reduced the incidence of the disease to very low levels. In Great Britain in 1978, 38 per cent of cattle were found to be affected in a survey of selected fatstock markets by the Meat and Livestock Commission. In 1985 the incidence had fallen to 0.01 per cent. Seven hundred and five affected herds were found in Great Britain when the disease was made notifiable in 1982, falling to 419 affected herds in 1985. Treatment of all cattle over 12 weeks old is required in affected herds. Since 1982 parts of Great Britain where the disease has persisted or where there is evidence of a recrudescence have been designated 'infected areas' in which all cattle over 12 weeks old have been required to be treated within specific dates. In addition to statutory measures the control measures in Great Britain include the inspection of cattle at auction markets and on farms. Work on the application to field conditions of an ELISA test is in progress, with encouraging results. It is considered that Great Britain is now well placed to eradicate warble fly.
Sera from 74,502 cattle from 3087 farms in England and Wales were tested for the presence of antibodies against Hypoderma bovis in the spring of 1988. Twenty-nine positive sera were identified on 18 premises and these animals were treated; an examination of 6030 sera taken from 108 neighbouring herds identified another 17 seropositive animals on 10 farms in Devon, Cornwall, Lancashire, Shropshire and Powys, indicating that these counties still harbour populations of warble fly.
The British warble fly eradication programme has resulted in the numbers of infested cattle falling from an estimated four million in 1978 to zero in 1991. In 1982, when about 705 herds were infested the disease was made notifiable, and serological surveillance was begun in 1988. In spring 1991, 227,000 blood samples were tested by using the ELISA technique and no warbled animals were found. In addition no clinical cases were reported during 1991.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
A serological survey was carried out to establish the prevalence of hypodermosis in Extremadura, a region of western Spain. Direct clinical methods and an enzyme linked immunosorbent assay (ELISA) were used to examine 1668 cattle between February 1992 and March 1993. An overall prevalence of 19.54 per cent was observed by the direct methods, and a prevalence of 42.3 per cent by the ELISA. The sensitivity and specificity of the ELISA for hypodermosis were assessed, and the fluctuation of antibody levels was studied throughout the year and correlated with the age of the host, the intensity of parasitism and the mean larval burden.
Sera from 100,400 cattle on 2850 farms in England, Scotland and Wales were tested for the presence of antibodies to Hypoderma species between the end of November 1995 and the end of February 1996. Twelve animals were resampled because the initial results were equivocal but only one of them was confirmed as seropositive. This animal was a bull imported from Belgium which had been treated with an approved warble fly treatment within 24 hours of arrival at its destination in Great Britain. No seropositive animals were confirmed within the native British cattle population. Statistical analysis of these data indicates that the probable maximum number of infested cattle herds in Great Britain is 112. To detect the disease by direct clinical observation would require more than 500 herds to be infested, indicating that the serological testing of this number of cattle and farms is more than four times as sensitive as clinical observation for the detection of hypodermosis.
Cross-reactivity between Hypoderma lineatum antigen and anti-Przhevalskiana silenus antibodies has been demonstrated by an ELISA technique. To evaluate the applicability of a commercial ELISA kit for the immunodiagnosis of goat warble fly infestation, different dilutions of serum and conjugate were tested, the development of antibody to P silenus in naturally infested goats was studied, and the results were compared with an ELISA technique using an antigen extracted from the first instar larvae of H lineatum. The best results were obtained with a serum dilution of 1:50; with both techniques the highest antibody concentration were recorded in October, November and December. In view of the confirmed cross-reactivity between H lineatum antigen and anti-P silenus antibodies, and the simplicity and rapidity of the assay, the commercial ELISA kit can be considered as a useful tool for the diagnosis of goat warble fly infestation.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.