12. Morphological Analysis of Sperm Cells

What are the two further classifications of spermatozoa based on the region of abnormality?

The two further classifications are primary forms and secondary forms. Primary forms occur due to disorders of the seminiferous or germinal epithelium, while secondary forms occur after the sperm has left the germinal epithelium, resulting from factors such as migration, ejaculation, or manipulation (e.g., overheating, rapid cooling, presence of water or urine).

What are spermatozoan head abnormalities?

1. Primary abnormalities


1. Microcephalic and macrocephalic head
2. Double or multiple heads
3. Elongated or narrow head
4. Piriform or pear-form shaped heads
5. Twisted, irregular-shaped head
6. Rounded short heads
7. Abnormal acrosomes: ruffled, incomplete, flattened, bent-over
8. Nuclear envelope invaginations: craters, puches, erosions
2. Secondary abnormalities


1. Detached or free heads: due to excessive agitation of semen sample, testicular degenration
2. Detached galea capitis and acrosome: India ink preparations

What are spermatozoan mid-piece abnormalities?

* Primary abnormalities
* Swollen neck: most serious abnormality
* Kinked neck
* Stubby mid-piece
* Naked neck
* Abaxial attachment of neck to head: common in stallions and boars
* Double mid- piece
* Kinked mid-piece
* “corkscrew” mid-piece: unusual
* Mid-piece with proximal or distal protoplasmic droplets: immature sperm cells, overuse
* Bent middle piece with/without protoplasmic droplets

What are spermatozoan tail abnormalities?

1. Primary abnormalities


1. Coiled tail
2. Tightly coiled tail
3. Double tail
4. Distal cytoplasmic or protoplasmic droplet: associated with infertility
5. Absent or short tail
2. Secondary abnormalities


1. Bent/ hairpin tail: associated with infrequent use of boar, cold shock
2. Broken tail: associated with infrequent use of boar