PMID: 7931917Oct 1, 1994Paper

Comparison of sequential, random, and hemacytometer methods for counting Cryptosporidium oocysts

The Journal of Parasitology
T C Kao, B L Ungar


In animal and clinical studies of Cryptosporidium infection, counting Cryptosporidium oocysts in collected fecal samples is often critical to interpretation of results and validity of statistical analyses. In this experiment, 3 methods of counting oocysts derived from feces of infected mice were compared. These included sequential counting of oocysts in 25 adjacent microscopic fields, random counting of oocysts in 25 scattered microscopic fields, and hemacytometer counting of oocysts using standard procedures. Numerical results are expressed as the numbers of oocysts per microscopic field for sequential and random counting methods or per microliter for the hemacytometer method. Our results showed that the numbers of oocysts adjusted for volume and weight, or for volume alone, were similar for all 3 techniques. Linear relationships between the 3 methods allow use of linear regression to convert the number of oocysts counted by 1 method into those counted by another. This suggests that comparisons between different experiments in which Cryptosporidium oocysts are counted using any of these methods are both possible and valid.

Related Concepts

Trending Feeds


Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.


Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.


Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.

Related Papers

Current Protocols in Toxicology
Han SeungMeredith Rocca
Journal of Visualized Experiments : JoVE
Richard Ricardo, Katy Phelan
The Journal of Allergy and Clinical Immunology
P LauferL L Hause
Methods in Cell Science : an Official Journal of the Society for in Vitro Biology
Melinda E FernyhoughMichael V Dodson
© 2021 Meta ULC. All rights reserved