- Semen Sample Collection
The semen diluent should be fresh, sterile, and stored at 5°C for no more than 72 hours. Samples should be diluted and aliquoted in the lab into 50μl or 25μl volumes, then stored and transported in liquid nitrogen.
- Semen Color and Odor Evaluation
Color: Normal semen is milky white to light gray, varying in opacity with density.
- Cattle/sheep semen: high density, thick milky or yellowish-white
- Pig/horse semen: lower density, pale milky or gray-white
Abnormal colors may indicate contamination or health issues:
- Greenish: pus contamination
- Yellow: urine contamination
- Red/pink: blood (stop collection)
- Reddish-brown: possible old injury
- Flaky material: possible seminal vesicle inflammation
Note: Jelly-like clots are common in pig/horse semen and usually normal.
Odor:
- Cattle and sheep: no distinct odor or mild sweaty smell
- Pigs and horses: slightly fishy
Foul or unusual odors may indicate infection—discard the sample and suspend collection.
- Sperm Concentration
Sperm concentration refers to the number of sperm cells per milliliter and directly influences dilution rates and fertility. It's a vital parameter for semen quality evaluation.
- Sperm Motility
Motility, or vitality, is the percentage of sperm showing forward movement. It directly affects the ability to fertilize and is a key metric in semen quality.
- Sperm Longevity and Survival Index
Sperm survival time is crucial for assessing fertilizing capability.
Method: Store fresh or thawed semen at 37–38°C, then assess motility at regular intervals until no motile sperm remain.
- Survival time = Total time from first to last check minus half of the final interval
- Survival index = Sum of (motility score × time interval) for all checks
- Sperm Morphology
Abnormal sperm morphology reduces fertility. Evaluation includes:
- Primary abnormalities (originating in the testes): large/small heads, double heads, acrosome defects, etc.
- Secondary abnormalities (post-ejaculation deformities)
- Tertiary abnormalities (due to improper storage): acrosome swelling or loss
Acrosome defects:
- Normal rates: ~5.9% in cattle, ~2.3% in pigs
- Post-preservation: can exceed 14% (cattle) or 4.3% (pigs), negatively affecting fertility
Let SQA-6100vet Handle It All
The SQA-6100vet is a fully automated, cutting-edge CASA system designed for livestock semen analysis. It features the world's only built-in heating stage, advanced Gaussian-based AI algorithms, precision microfluidic counting chips, and autofocus technology. Capable of analyzing sperm concentration, total count, motility, motion characteristics, and even morphology with speed and accuracy, it supports raw semen testing and automatically calculates optimal dilution and distribution ratios—streamlining the entire testing process from start to finish.