Nematode parasites and faecal soiling of sheep in lairage: evidence of widespread potential production losses for the sheep industry

2009 ◽  
Vol 49 (4) ◽  
pp. 326 ◽  
Author(s):  
C. L. Jacobson ◽  
K. Bell ◽  
R. B. Besier
Keyword(s):  
Winter Rainfall ◽  
Faecal Pellets ◽  
Sheep Industry ◽  
Adult Sheep ◽  
Nematode Parasites ◽  
Parasite Infections ◽  
Faecal Soiling ◽  
Nematode Worm ◽  
Normal Adults ◽  
Production Losses

Diarrhoea (scouring) and subsequent faecal soiling of fleece are important economic and welfare issues for the sheep industry. Nematode worm infections are commonly implicated as a cause of scouring. This study aimed to investigate the extent of strongyle parasite infections, and identify any association with faecal worm egg count (WEC) and scouring in sheep from winter rainfall environments in Western Australia consigned to an abattoir. Faeces were collected from sheep with evidence of scouring and normal sheep (firm faecal pellets and no evidence of fresh diarrhoea on breech). A total of 4430 sheep from 113 lines of lambs (<12 months old), 10 lines of yearlings (12–24 months old) and 235 lines of adult sheep (>24 months old) were sampled between September and January. Mean WEC in lamb lines was 1525 eggs per gram (epg) of faeces with mean WEC >1000 epg in 42% of lines and >2000 in 22% of lines. Mean WEC in adult lines was 486 epg, with 13% lines having mean WEC >1000 epg. There was a trend (P = 0.099) to higher WEC in scouring lambs (2289 epg) compared with normal lambs (1523 epg). The scouring adult sheep had lower WEC (417 epg) compared with normal adults (482 epg, P = 0.021). The findings suggest that large strongyle infections were common in lambs consigned for slaughter. The low WEC in scouring adult sheep was consistent with the suggestion that a hypersensitivity to ingested nematode larvae, rather than large worm burdens, may be responsible for scouring in mature sheep.

The inheritance of faecal egg count following natural Ostertagia circumcinctainfection in Scottish Blackface lambs

1996 ◽  
Vol 1996 ◽  
pp. 117-117
Author(s):  
S.C. Bishop ◽  
K. Bairden ◽  
Q.A. McKellar ◽  
M. Park ◽  
M.J. Stear
Keyword(s):  
Genetic Selection ◽  
Live Weight ◽  
Gastrointestinal Parasites ◽  
Sheep Industry ◽  
Environment Effects ◽  
Faecal Egg Count ◽  
Genetic And Phenotypic Correlations ◽  
Selection For ◽  
The Uk ◽  
Production Losses

The use of genetic selection as a means of reducing the welfare and production losses caused by gastrointestinal parasites has hitherto been ignored by the UK sheep industry. The aim of this study is to assess the potential for selection for reduced faecal egg count, as an indicator of parasitism, and to establish relationships with live weight.Faecal egg counts and live weights were measured on approximately 200 predominantly twin born Scottish Blackface lambs each year for three years following natural, predominantly Ostertagia circumcincta , infection on pasture. Measurements were made from one to six months of age, at four week intervals, following anthelmintic treatment. Heritabilities, maternal common environment effects, genetic and phenotypic correlations were calculated using Residual Maximum Likelihood techniques.

The inheritance of faecal egg count following natural Ostertagia circumcinctainfection in Scottish Blackface lambs

1996 ◽  
Vol 1996 ◽  
pp. 117-117
Author(s):  
S.C. Bishop ◽  
K. Bairden ◽  
Q.A. McKellar ◽  
M. Park ◽  
M.J. Stear
Keyword(s):  
Genetic Selection ◽  
Live Weight ◽  
Gastrointestinal Parasites ◽  
Sheep Industry ◽  
Environment Effects ◽  
Faecal Egg Count ◽  
Genetic And Phenotypic Correlations ◽  
Selection For ◽  
The Uk ◽  
Production Losses

The use of genetic selection as a means of reducing the welfare and production losses caused by gastrointestinal parasites has hitherto been ignored by the UK sheep industry. The aim of this study is to assess the potential for selection for reduced faecal egg count, as an indicator of parasitism, and to establish relationships with live weight.Faecal egg counts and live weights were measured on approximately 200 predominantly twin born Scottish Blackface lambs each year for three years following natural, predominantly Ostertagia circumcincta , infection on pasture. Measurements were made from one to six months of age, at four week intervals, following anthelmintic treatment. Heritabilities, maternal common environment effects, genetic and phenotypic correlations were calculated using Residual Maximum Likelihood techniques.

Habitat overlap and gastrointestinal parasitism in sympatric African bovids

Parasitology ◽  
2003 ◽  
Vol 126 (4) ◽  
pp. 379-388 ◽  
Author(s):  
V. O. EZENWA
Keyword(s):  
Host Species ◽  
Positive Association ◽  
New Host ◽  
Habitat Overlap ◽  
Nematode Parasites ◽  
Parasite Richness ◽  
Individual Probability ◽  
Parasitism Rates ◽  
Specific Contact ◽  
Parasite Infections

Gastrointestinal parasite infections are widespread among wild ungulates. Because many of these parasites infect multiple host species, inter-specific interactions among hosts potentially play an important role in parasite transmission dynamics in ungulate communities. In this study, the effects of inter-specific contact on parasitism rates in 11 sympatric African bovids was examined using habitat overlap among species as a measure of cross-species contact rates. Across individual hosts, strongyle nematode abundance increased with increasing numbers of bovid species occupying a habitat. Furthermore, comparative analyses show a positive association between strongyle prevalence and level of habitat overlap across taxa. These findings suggest that among sympatric bovids, contact between species contributes significantly to the transmission of generalist nematode parasites. For a more host-specific parasite group, coccidia, parasite abundance and individual probability of infection declined in hosts living in bovid rich habitats. This pattern may reflect enhanced inter-specific competition among parasites in these areas. Finally, similar to strongyle abundance, individual parasite richness also increased among hosts occupying habitats with higher numbers of bovid species. No association between habitat overlap and parasite richness was detected at higher taxonomic scales, however, which suggests that contact between host species may not contribute to parasite colonization of new host taxa.

Populations of free-living stages of Ostertagia ostertagi and O. circumcincta in a winter rainfall region

1983 ◽  
Vol 34 (5) ◽  
pp. 569 ◽  
Author(s):  
RR Young
Keyword(s):  
Population Dynamics ◽  
Survival Rate ◽  
Larval Survival ◽  
Moisture Loss ◽  
Free Living ◽  
Winter Rainfall ◽  
Faecal Pellets ◽  
Infective Larvae ◽  
Cattle Faeces ◽  
Rainfall Region

Pats of cattle faeces containing eggs of the trichostrongylid Osferfagia ostertagi and deposits of sheep faecal pellets containing eggs of O. circumcincta were placed on dry and irrigated pasture plots at four times during the period October 1977 to February 1978. Faecal pellets lost moisture far more rapidly than did dung pats. The rate of moisture loss from both faecal deposits was greater on dry plots than on irrigated plots. Despite large differences between irrigated and dry plots in soil temperature and soil and pasture moisture status, the temperatures recorded in both dung pats and faecal pellets were similar on all plots at each time of deposition. A significantly greater proportion of O . circumcincta eggs was recovered as infective larvae in faeces, on herbage and in soil compared with that of O. osterfagi eggs. Irrigation did not result in either substantially more eggs developing to infective larvae in faeces or higher recoveries of larvae from herbage and soil. No significant differences were detected in temperature or moisture measurements or in parameters of free-living development and larval survival between plots with long or short pasture herbage. There were marked differences between the population dynamics of the infective larvae of Ostertagia spp. and between the numbers of larvae on irrigated and dry plots. On dry plots, O . circumcincta migrated in abundance from faecal deposits after smaller falls of rain than were required for migration of O . ostertagi larvae. Larvae of both species persisted in abundance on the herbage of most dry plots until late spring. On irrigated plots, migration of both species of larvae occurred immediately and was independent of rainfall, but survival rate of larvae was lower than on the corresponding dry plots.

scholarly journals PARASITIC NEMATODE INFECTIONS OF ANURANS FROM A DERIVED SAVANNA BIOTOPE IN EDO STATE, NIGERIA

2021 ◽  
Vol 2 (2) ◽  
pp. 166-182
Author(s):  
H. J. Ozemoka ◽  
M. S. O. Aisien
Keyword(s):  
New Record ◽  
Sampling Method ◽  
Parasitic Nematode ◽  
Nematode Species ◽  
Wet Season ◽  
Nematode Parasites ◽  
Derived Savanna ◽  
Parasite Infections ◽  
Edo State ◽  
Cosmocerca Ornata

As part of a broader study to increase the information of parasite infections of anurans from the savanna biotope, an investigation of the nematode parasites of anurans in Agbede, a location in the derived savanna of Edo State, Nigeria was undertaken from August 2007 to July 2008. Anurans were collected at night using the visual acoustic encounter survey (VAES) sampling method, dissected and examined for nematode infections. A total of 329 anurans belonging to sixteen taxa, were examined, of which 235 were infected with an overall prevalence of 71.43%. Seasonal prevalences were 85.63% for wet season and 52.48% for the dry season (p<0.05). Ten nematode species, namely: Amplicaecum africanum, Cosmocerca ornata, Oswaldocruzia hoeplii, Physaloptera sp., Rhabdias africanus, Rhabdias sp., Camallanus dimitrovi, an unidentified oxyurid nematode, Ophidascaris larva, and an unidentified nematode were recovered from the hosts examined. The most common nematode species was Amplicaecum africanum (31.31%), whereas the least common was an unidentified oxyurid nematode (0.30%).Physaloptera sp. is a new record for the anurans of the derived savanna.

scholarly journals Nematode parasites reduce carotenoid-based signalling in male red grouse

2007 ◽  
Vol 3 (2) ◽  
pp. 161-164 ◽  
Author(s):  
Jesús Martínez-Padilla ◽  
François Mougeot ◽  
Lorenzo Pérez-Rodríguez ◽  
Gary R Bortolotti
Keyword(s):  
Nematode Parasite ◽  
Negative Effects ◽  
Free Living ◽  
Red Grouse ◽  
Carotenoid Concentration ◽  
Nematode Parasites ◽  
Parasite Infections ◽  
Lagopus Lagopus Scoticus ◽  
Trichostrongylus Tenuis ◽  
First Time

Carotenoids determine the yellow–red colours of many ornaments, which often function as signals of quality. Carotenoid-based signalling may reliably advertise health and should be particularly sensitive to parasite infections. Nematodes are among the commonest parasites of vertebrates, with well-documented negative effects on their hosts. However, to date, little is known about the effects that these parasites may have on carotenoid-based signalling. Tetraonid birds (grouse) exhibit supra-orbital combs, which are bright integumentary ornaments pigmented by carotenoids. We tested the effect of the nematode parasite Trichostrongylus tenuis on signalling in free-living male red grouse Lagopus lagopus scoticus . We show that experimentally reduced nematode infection increases plasma carotenoid concentration and comb redness, demonstrating for the first time that nematodes can influence carotenoid-based signals.

scholarly journals Host immune responses to nematodes: benefit or cost? Implications for future development of sustainable methods of control

2010 ◽  
Vol 39 (suppl spe) ◽  
pp. 376-382 ◽  
Author(s):  
Andrew R. Sykes
Keyword(s):  
Immune Response ◽  
Immune Responses ◽  
Genetic Selection ◽  
Production Costs ◽  
Host Immune Responses ◽  
Nematode Parasites ◽  
Nutritional Environment ◽  
Cost Implications ◽  
Production Losses ◽  
Methods Of Control

The nutritional and production costs associated with the development of a competent immune response against nematode parasites is described, based on data from sheep. Anorexia and changes in metabolism are considered to be driven by the host immune response itself and the question is raised about the wisdom of seeking to strengthen immune responses by genetic selection. Several phases of the immune response are identified with different implications for loss of productivity and opportunity for moderation of immune responses and production losses by nutrition. Many animals are able to manage nematode infections with little loss of productivity. In an era when attempts are being made to reduce anthelmintic use and create refugia to reduce the rate of development of drench resistance, treatments based on individual animal performance relative to production targets set by assessment of the prevailing nutritional environment will become more common. These developments, have already occurred in relation to the haematophagic nematodes, for example the "Famacha" technique. Computer-aided weighing and drafting has potential for use with the less pathogenic nematodes prevalent in temperate regions though we need to know more about the pathophysiology and nutritional costs of infections with Nematodirus spp.

Nematode parasite control in weaner cattle on the Northern Tablelands of New South Wales

1979 ◽  
Vol 19 (98) ◽  
pp. 269 ◽  
Author(s):  
FL Bowen
Keyword(s):  
Growth Rate ◽  
New South ◽  
Early Summer ◽  
Parasite Infection ◽  
Parasite Control ◽  
Regular Treatment ◽  
South Wales ◽  
Two Factors ◽  
Parasite Infections ◽  
Production Losses

An indication of the extent to which parasite infection can limit production in yearling cattle was studied by comparing a monthly treatment with cambendazole with non-treated control cattle. In the same experiment the technique of limiting parasite infections by alternate grazing of pastures by sheep and cattle was studied. Growth rate of monthly treated cattle (0.667 kg day-1) was significantly (P < 0.05) greater than for untreated cattle (0.421 kg day-1) over the 12-month period of the trial. The mortality of 12.5% in untreated animals was avoided by regular treatment. These two factors resulted in a marked financial advantage to monthly treated cattle. Ostertagia ostertagi, as the major nematode involved, produced production losses primarily in the spring and early summer periods. The alternation of sheep and cattle grazing gave an advantage over set stocked cattle in both liveweight gain and financial returns, but did not prevent mortalities in untreated cattle.

scholarly journals In silico analyses of neuropeptide-like protein (NLP) profiles in parasitic nematodes

2021 ◽  
Author(s):  
Fiona M McKay ◽  
Ciaran J McCoy ◽  
Nikki J Marks ◽  
Aaron G Maule ◽  
Louise E Atkinson ◽  
...  
Keyword(s):  
Drug Targets ◽  
Anthelmintic Resistance ◽  
Physiological Activity ◽  
Nematode Species ◽  
Nematode Parasite ◽  
Parasitic Nematodes ◽  
Global Food Security ◽  
Nematode Parasites ◽  
Parasite Infections ◽  
Novel Drug

Nematode parasite infections cause disease in humans and animals and threaten global food security by reducing productivity in livestock and crop farming. The escalation of anthelmintic resistance in economically important nematode parasites underscores the need for the identification of novel drug targets in these worms. Nematode neuropeptide signalling is an attractive system for potential chemotherapeutic exploitation, with neuropeptide G-protein coupled receptors (NP-GPCRs) representing the leading target candidates therein. In order to successfully validate NP-GPCRs as targets for parasite control it is necessary to characterise their function and importance to nematode biology. This can be aided through identifying receptor activating ligand(s) in a process known as receptor deorphanisation. Such efforts first require the identification of all neuropeptide ligands within parasites. Here we comb the genomes of nine therapeutically relevant pathogenic nematode species to comprehensively characterise the nematode parasite neuropeptide-like protein (NLP) complements, and details the discovery of several previously unreported, yet conserved, neuropeptides and neuropeptide-encoding genes. We identify the neuropeptides that are most highly conserved in all parasites examined, and characterise their physiological activity on the reproductive musculature of the parasite, Ascaris suum. These data suggest conserved neuropeptide functions in both free living and parasitic nematodes, and support the potential for exploitation of the neuropeptide signalling system as an anthelmintic target.

Nematode parasites of sheep: a survey of epidemiological parameters and their application in a simple model

Parasitology ◽  
2000 ◽  
Vol 121 (1) ◽  
pp. 85-103 ◽  
Author(s):  
R. R. KAO ◽  
D. M. LEATHWICK ◽  
M. G. ROBERTS ◽  
I. A. SUTHERLAND
Keyword(s):  
New Zealand ◽  
Domestic Sheep ◽  
Winter Rainfall ◽  
Climate Type ◽  
Data Set ◽  
Nematode Parasites ◽  
The Uk ◽  
Parameter Values ◽  
Rainfall Region ◽  
Made In

We review the literature on parameter values relevant to the epidemiology of strongyle nematode infections of domestic sheep. Information is subdivided by parasite genus, country of origin and climate type. While field observations have been made in a large number of countries, the bulk of studies under controlled conditions have been conducted in Australia, New Zealand and the UK. For these countries, experiments and parameters are interpreted in terms of a previously published model of nematode dynamics, and are used to calculate the basic reproduction number. Average values range from less than 6 for Haemonchus contortus in New Zealand and a winter rainfall region of Australia, to more than 16 for Ostertagia circumcincta in New Zealand and the UK. Additional considerations of the effects of climate and the annual replacement of host stock show that for conditions favourable for parasite transmission this is a robust indicator of parasite epidemiology. When climate variation and annual replacement are added to the model, it is shown to reasonably describe the qualitative behaviour of an experimental data set, indicating it to be a useful tool for further investigation of some of the underlying assumptions of sheep–nematode dynamics.

Sign in / Sign up

Export Citation Format

Share Document