Conteo de espermatozides en la cámara de Neubaur

Summary

This video guides viewers through the process of counting spermatozoa using a microscope and calculating sperm concentration. The speaker explains how to handle dilution factors and validate the accuracy of counts by comparing results from multiple trials. Using practical examples, the video shows how to calculate the final concentration of sperm based on the number of sperm counted, the number of fields observed, and the dilution factor. The speaker emphasizes ensuring that the difference in counts is within a permissible margin, ensuring reliable results for accurate sperm concentration analysis.

Takeaways

• 😀 Proper sperm counting requires ensuring the difference between counts is within an acceptable range for validity.
• 😀 If the count difference exceeds the maximum allowed, the test result is invalid and needs to be repeated.
• 😀 Dilution is essential for counts greater than 100 sperm per field, typically using a 1:20 dilution factor.
• 😀 The maximum allowed difference for two sperm counts can be found in a reference table, which ensures the count is accurate.
• 😀 When calculating sperm concentration, the number of sperm counted is divided by the number of rows counted.
• 😀 The volume per field is considered in the calculations to determine the total sperm concentration per milliliter.
• 😀 For counts above 100, a 1:20 dilution factor is used to adjust the sperm concentration calculation.
• 😀 For smaller dilution factors (e.g., 1:2), more rows need to be counted to maintain accuracy in the sperm concentration estimate.
• 😀 The calculation for sperm concentration is expressed in millions of sperm per milliliter (10^6 sperm/mL).
• 😀 When performing counts, it is essential to use an appropriate formula that factors in dilution and the number of rows counted for accurate results.
• 😀 In practice, formulas and tables are used to ensure the sperm concentration is calculated correctly and consistently across multiple counts.

Q & A

What is the purpose of the video?

The purpose of the video is to explain the process of performing sperm count calculations, ensuring accuracy by following the correct counting procedure and using dilution factors. The video guides the viewer through different examples and the related calculations.

Why is it important to check if the difference in sperm counts is valid?

It is important to check if the difference in sperm counts is within an acceptable range to ensure the accuracy of the test. A count difference that exceeds the allowed range can lead to incorrect conclusions about the sperm concentration and the need for a recount.

What is the maximum allowable difference between two sperm counts?

The maximum allowable difference between two sperm counts is 41. If the difference exceeds this value, the counts are considered invalid, and the test must be redone.

How do you calculate sperm concentration when the sperm count is high?

When the sperm count is high (over 100), a dilution factor of 1:20 is typically used. To calculate the sperm concentration, divide the total sperm count by the number of rows counted and multiply by the dilution factor, then divide by the volume of one row.

What formula is used to calculate sperm concentration?

The formula for calculating sperm concentration is: Concentration (sperm/ml) = (Total sperm count / Number of rows) * (1 / Volume per row * Dilution factor).

What does the volume per row refer to in the calculation?

The volume per row refers to the specific amount of sample that fits into a row on the counting chamber, which is typically measured in nanoliters. In this case, the volume per row is 20 nanoliters.

How does the dilution factor affect the calculation?

The dilution factor is used to account for how much the sperm sample has been diluted before counting. A dilution factor of 1:20 means that the sample has been diluted 20 times. This factor is included in the calculation to adjust the final sperm concentration to its true value in the undiluted sample.

What would happen if the sperm count was less than 100?

If the sperm count is less than 100, a different dilution factor, such as 1:2, is used, and all quadrants (or sub-chambers) of the counting chamber must be counted to ensure a sufficient sample size for accurate results.

What is the final sperm concentration in the example where 447 sperm were counted in four rows?

In the example, the sperm concentration is calculated as 447 sperm counted over 4 rows, which results in a concentration of 111.7 million sperm/ml, or 111 x 10^6 sperm/ml.

How does the speaker conclude the video?

The speaker concludes the video by thanking the viewers, expressing hope that the video was helpful, and encouraging viewers to like, share, and subscribe to the YouTube channel to support the channel and help the speaker continue their work.