SynthesisParasites & vectors2017
Meta-analysis of the parasitic phase traits of Haemonchus contortus infection in sheep.
Synthesis in Parasites & vectors, 2017. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 9 papers, 1 of them a synthesis that pooled it.
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Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
9 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Systematic review of the prevalence of Gastrointestinal helminths in ruminants in Mexico.Veterinary research communications · 2025Pooled it
- Inferring the energy cost of resistance to parasitic infection and its link to a trade-off.BMC ecology and evolution · 2025Article
- Understanding Animal-Plant-Parasite Interactions to Improve the Management of Gastrointestinal Nematodes in Grazing Ruminants.Pathogens (Basel, Switzerland) · 2023Review
- Comparative analysis of helminth infectivity: growth in intermediate hosts increases establishment rates in the next host.Proceedings. Biological sciences · 2021Article
- Potentials of using milk performance data and FAMACHA score as indicators for Targeted Selective Treatment in Lacaune dairy sheep in Switzerland.Veterinary parasitology: X · 2020Article
- Ovine haemonchosis: a review.Tropical animal health and production · 2020Review
- Reduced egg shedding in nematode-resistant ewes and projected epidemiological benefits under climate change.International journal for parasitology · 2019Article
- The global diversity of Haemonchus contortus is shaped by human intervention and climate.Nature communications · 2019Article
- Prediction and attenuation of seasonal spillover of parasites between wild and domestic ungulates in an arid mixed-use system.The Journal of applied ecology · 2018Article
Corrections and comments
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Authors and funding
8 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThe parasitic nematode Haemonchus contortus shows highly variable life history traits. This highlights the need to have an average estimate and a quantification of the variation around it to calibrate epidemiological models.
methodsThis paper aimed to quantify the main life history traits of H. contortus and to identify explanatory factors affecting these traits using a powerful method based on a systematic review and meta-analysis of current literature. The life history traits considered are: (i) the establishment rate of ingested larvae; (ii) the adult mortality rate; (iii) the fertility (i.e. the number of eggs laid/female/day); and (iv) fecundity of female worms (i.e. the number of eggs per gram of faeces).
resultsA total of 37 papers that report single experimental infection with H. contortus in sheep and published from 1960 to 2015, were reviewed and collated in this meta-analysis. This encompassed 115 experiments on 982 animals. Each trait was analysed using a linear model weighted by its inverse variance. The average (± SE) larval establishment rate was 0.24 ± 0.02, which decreased as a function of the infection dose and host age. An average adult mortality rate of 0.021 ± 0.002) was estimated from the literature. This trait varied as a function of animal age, breed and protective response due to prior exposure to the parasite. Average female fertility was 1295.9 ± 280.4 eggs/female/day and decreased in resistant breeds and previously infected hosts. Average faecal egg count at necropsy was 908.5 ± 487.1 eggs per gram of faeces and varied as a function of infection duration and host resistance. The average sex ratio of H. contortus was 0.51 ± 0.006.
conclusionThis work is the first systematic review to summarise the available information on the parasitic phase of H. contortus in sheep. The results of the meta-analysis provide robust estimates of life history traits for parametrization of epidemiological models, their expected variation according to experimental factors, and provides correlations between these.
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