A study of helminth parasites in culled cows from Ireland
ABSTRACT The objective of this study was to determine the prevalence and intensity of gastrointestinal nematode, lungworm and liver fluke infection in culled cows in Ireland. Abomasa, colorectal contents and livers were collected from 30 to 68 culled beef and dairy cows during autumn 2002 and summer 2003, respectively. Ostertagia ostertagi were found in the abomasa of only three (10%) cows sampled in autumn and in 38 (57%) cows examined in summer. The majority of positive animals had low burdens of O. ostertagi but a few individuals in the group sampled during the summer had a moderate infection (5000-10,000 adult worms). A proportion of the cows in the summer group were also co-infected with small numbers of Trichostrongylus axei. Cooperia oncophora predominated in the recoveries from the larval cultures although O. ostertagi were also recovered. The overall prevalence of Dictyocaulus viviparus was 14%, based on larval identification in faecal samples. Liver fluke, or varying degrees of pathology attributable to Fasciola hepatica, were present in 65% of the livers. The results of this study extend those of previous workers, which were largely limited to dairy cows alone and which focussed on gastrointestinal nematodes and did not include simultaneous infections with lungworm and liver fluke. It was concluded, from the level of polyparasitism evident in this study, that adult cattle should be considered in preventative approaches to bovine helminthosis.
- SourceAvailable from: Barbara Good
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- "Data on the prevalence of D. viviparus and O. ostertagi infections in Irish dairy herds are limited. The most recent study recorded post-mortem prevalence at abattoirs of 14% and up to 59% for D. viviparus and O. ostertagi, respectively (Murphy et al., 2006). Specific data on geographical and seasonal trends in D. viviparus and O. ostertagi infection in Ireland are not available. "
ABSTRACT: Infections with Dictyocaulus viviparus and Ostertagia ostertagi nematode parasites are of importance to bovine health and production in temperate areas across the world. Losses due to these parasites in dairy herds can be considerable due to decreased milk productivity and fertility. However, information on current epidemiological patterns in Irish dairy herds is limited. Bulk milk samples were collected from a total of 319 dairy farms across the Republic of Ireland. The D. viviparus samples were tested with an ELISA based on recombinant major sperm protein, while the O. ostertagi samples were tested with an ELISA based on crude saline extract, whole worm O. ostertagi antigen. Management data were collected from the farms using a questionnaire. Logistic regression was used to find significant associations between the presence of antibodies against D. viviparus and O. ostertagi and management factors. The overall prevalence of D. viviparus infection was 62.8%, while over 98% of herds had antibodies to O. ostertagi at the specified cut-off. Both D. viviparus and O. ostertagi antibodies were highest in November, which could be explained by the accumulated uptake of larvae through the grazing season. In herds of farmers that dosed their in-calf heifers with anthelmintics were significantly more likely to be positive for antibodies against D. viviparus infection. This study highlights that both D. viviparus and O. ostertagi infections are widespread in dairy herds in Ireland throughout the grazing season. Copyright © 2015 Elsevier B.V. All rights reserved.Veterinary Parasitology 02/2015; 209(1-2). DOI:10.1016/j.vetpar.2015.01.021 · 2.55 Impact Factor
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- "Helminth parasites cause >55% of all farm animal diseases in Europe and effective control strategies would have a major impact on the sustainability of the livestock industry (Nieuwhof and Bishop, 2005; Murphy et al., 2006; Morgan et al., 2013). In Europe, parasitic diseases of farm animals are caused principally by infections with the liver fluke Fasciola hepatica, the lungworm Dictyocaulus viviparus, and the gastrointestinal nematode parasites of sheep (Haemonchus contortus, Teladorsagia circumcincta) and cattle (Ostertagia ostertagi, Cooperia oncophora). "
ABSTRACT: Major advances have been made in identifying potential vaccine molecules for the control of fasciolosis in livestock but we have yet to reach the level of efficacy required for commercialisation. The pathogenesis of fasciolosis is associated with liver damage that is inflicted by migrating and feeding immature flukes as well as host inflammatory immune responses to parasite-secreted molecules and tissue damage alarm signals. Immune suppression/modulation by the parasites prevents the development of protective immune responses as evidenced by the lack of immunity observed in naturally and experimentally infected animals. In our opinion, future efforts need to focus on understanding how parasites invade and penetrate the tissues of their hosts and how they potentiate and control the ensuing immune responses, particularly in the first days of infection. Emerging 'omics' data employed in an unbiased approach are helping us understand liver fluke biology and, in parallel with new immunological data, to identify molecules that are essential to parasite development and accessible to vaccine-induced immune responses. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.Veterinary Parasitology 01/2015; 36(1-2). DOI:10.1016/j.vetpar.2015.01.004 · 2.55 Impact Factor
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- "One generalisation that can be applied to all the regions is that younger cattle are typically more susceptible to clinical parasitic disease than adults, because they lack functional, acquired immunity to some nematode species until they have been exposed to infection for several months (Armour, 1989). Another generalisation is that, while adult cows are considered less susceptible to PGE insofar as they rarely suffer from clinical disease, they do, however, commonly harbour significant worm populations , particularly of Ostertagia ostertagi in the abomasum (Agneessens et al., 2000; Borgsteede et al., 2000; Burrows et al., 1980; Murphy et al., 2006). Furthermore, recent research has shown that over a third of adult cattle at slaughter have extensive gross, pathological changes in the abomasal mucosa, typical of ostertagiosis (Larraillet et al., 2012). "
ABSTRACT: An extended-release injection, which is administered at a rate of 1mg eprinomectin/kg body weight, has been developed to provide up to 150 days control of parasites of cattle. The product can facilitate the achievement of two of the fundamental aims of parasite control. The first is protection of the host against the negative impact of susceptible parasites in order to ensure control of disease and to enhance performance. The second is to reduce parasite transmission and hence the challenge to animals when grazing. In addition, farmers and veterinarians can benefit from high levels of convenience and hence compliance from a single administration, which also limits handling stress in the cattle. This introductory paper provides some perspective on the practical applications for this extended-release product under various husbandry systems and in different classes of cattle and discusses its role in sustainable parasite control.Veterinary Parasitology 12/2012; 192(4). DOI:10.1016/j.vetpar.2012.11.036 · 2.55 Impact Factor