Inhomogeneity of the density of Parascaris spp. eggs in faeces of individual foals and the use of hypothesis testing for treatment decision making.
Abstract: Faecal egg counts (FEC) are used widely for monitoring of parasite infection in animals, treatment decision-making and estimation of anthelmintic efficacy. When a single count or sample mean is used as a point estimate of the expectation of the egg distribution over some time interval, the variability in the egg density is not accounted for. Although variability, including quantifying sources, of egg count data has been described, the spatiotemporal distribution of nematode eggs in faeces is not well understood. We believe that statistical inference about the mean egg count for treatment decision-making has not been used previously. The aim of this study was to examine the density of Parascaris eggs in solution and faeces and to describe the use of hypothesis testing for decision-making. Faeces from two foals with Parascaris burdens were mixed with magnesium sulphate solution and 30 McMaster chambers were examined to determine the egg distribution in a well-mixed solution. To examine the distribution of eggs in faeces from an individual animal, three faecal piles from a foal with a known Parascaris burden were obtained, from which 81 counts were performed. A single faecal sample was also collected daily from 20 foals on three consecutive days and a FEC was performed on three separate portions of each sample. As appropriate, Poisson or negative binomial confidence intervals for the distribution mean were calculated. Parascaris eggs in a well-mixed solution conformed to a homogeneous Poisson process, while the egg density in faeces was not homogeneous, but aggregated. This study provides an extension from homogeneous to inhomogeneous Poisson processes, leading to an understanding of why Poisson and negative binomial distributions correspondingly provide a good fit for egg count data. The application of one-sided hypothesis tests for decision-making is presented.
Copyright © 2016 Elsevier B.V. All rights reserved.
Publication Date: 2016-10-11 PubMed ID: 27809968DOI: 10.1016/j.vetpar.2016.10.010Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Journal Article
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
The research investigates the inconsistency in the density of Parascaris eggs in the faeces of foals. It also presents a new approach to decision-making via hypothesis testing based on this inconsistency.
Objectives and Methodology
- This study was conducted to analyze the density of Parascaris eggs present in foal faeces and solution mixes, as well as to explore the effectiveness of hypothesis testing in guiding treatment decisions.
- The researchers gathered data by combining faeces from two Parascaris-infested foals with a magnesium sulphate solution. Thirty McMaster chambers were used to study the egg distribution in this well-blended solution.
- Additionally, 81 counts were conducted from three faecal piles from a single foal with a known Parascaris burden, and the egg dispersal within the faeces was studied.
- Another part of the study involved collecting faecal samples from 20 foals over three consecutive days. Faecal egg counts were carried out thrice on each sample to approximate parasite infection levels.
- Finally, Poisson or negative binomial confidence intervals were calculated for the distribution mean, depending on what was appropriate.
Findings and Conclusions
- The study found that the distribution of eggs in a well-compounded solution follows a homogeneous Poisson process. In contrast, the distribution in foal faeces was not uniform and showed evidence of clustering.
- The researchers used this newfound understanding of egg distribution to transition from a homogeneous Poisson process to an inhomogeneous one, as the latter provided a better fit for the egg count data.
- The research went further to demonstrate the practical application of one-sided hypothesis testing in making treatment decisions based on these findings.
- In essence, the research provides valuable insights into the distribution of Parascaris eggs in faeces, improving our understanding of parasite egg density variation. Furthermore, it demonstrates the potential utility of hypothesis testing in guiding treatment decisions.
Cite This Article
APA
Wilkes EJA, Cowling A, Woodgate RG, Hughes KJ.
(2016).
Inhomogeneity of the density of Parascaris spp. eggs in faeces of individual foals and the use of hypothesis testing for treatment decision making.
Vet Parasitol, 229, 131-138.
https://doi.org/10.1016/j.vetpar.2016.10.010 Publication
Researcher Affiliations
- School of Animal & Veterinary Sciences, Charles Sturt University, Locked Bag 588, Wagga Wagga, New South Wales 2678, Australia. Electronic address: ewilkes@csu.edu.au.
- School of Animal & Veterinary Sciences, Charles Sturt University, Locked Bag 588, Wagga Wagga, New South Wales 2678, Australia.
- School of Animal & Veterinary Sciences, Charles Sturt University, Locked Bag 588, Wagga Wagga, New South Wales 2678, Australia.
- School of Animal & Veterinary Sciences, Charles Sturt University, Locked Bag 588, Wagga Wagga, New South Wales 2678, Australia.
MeSH Terms
- Animals
- Anthelmintics / administration & dosage
- Anthelmintics / therapeutic use
- Ascaridida Infections / diagnosis
- Ascaridida Infections / parasitology
- Ascaridida Infections / veterinary
- Ascaridoidea / isolation & purification
- Decision Making
- Feces / parasitology
- Horse Diseases / diagnosis
- Horse Diseases / parasitology
- Horses
Citations
This article has been cited 2 times.- Özben M, von Samson-Himmelstjerna G, Freiin von Streit MKB, Wilkes EJA, Hughes KJ, Krücken J. Absence of Polymorphisms in Codons 167, 198 and 200 of All Seven β-Tubulin Isotypes of Benzimidazole Susceptible and Resistant Parascaris spp. Specimens from Australia.. Pathogens 2022 Apr 20;11(5).
- Saeed MA, Beveridge I, Abbas G, Beasley A, Bauquier J, Wilkes E, Jacobson C, Hughes KJ, El-Hage C, O'Handley R, Hurley J, Cudmore L, Carrigan P, Walter L, Tennent-Brown B, Nielsen MK, Jabbar A. Systematic review of gastrointestinal nematodes of horses from Australia.. Parasit Vectors 2019 Apr 29;12(1):188.
Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists
