Spermatozoon

The spermatozoon is the male reproductive cell of the dog, which transports the paternal genetic material to the egg during mating. For breeders, the quality of these sperm cells determines breeding success, as only healthy, motile sperm can bring about fertilisation.

How is a spermatozoon structured?

A sperm consists of three parts that must work in perfect coordination. The head carries 39 chromosomes and the acrosome, an enzyme cap that later penetrates the egg envelope. The middle piece is packed with mitochondria that provide energy for swimming movement. The whip-like tail propels the sperm forward.

In healthy male dogs, sperm contain exactly half of the normal set of chromosomes. This is why fertilisation works: 39 chromosomes from the father plus 39 from the mother result in the full 78 chromosomes of the puppy.

How are sperm produced in the male dog?

Sperm production takes place continuously in the testes and lasts about 62 days from start to mature sperm. This process begins with puberty, usually between the 6th and 12th month of life, depending on the breed.

The immature sperm cells go through several stages of maturation and finally end up in the epididymis. There they can be stored for up to 60 days without losing their fertilising ability. This explains why older male dogs remain fertile if they are in good health.

How do I recognise fertility problems in my male dog?

Several unsuccessful mating attempts are the clearest warning signal. But physical signs can also indicate problems: testes of unequal size, hardened areas in the scrotum or pain on palpation.

In breeding male dogs, you should watch out for changes in behaviour. A suddenly uninterested male dog or problems during mating can indicate hormonal disorders. Overweight, chronic diseases or severe stress significantly impair sperm quality.

From the 7th year of life, fertility naturally decreases. This is normal; the number of sperm drops and motility declines.

What examinations are available for fertility problems?

The first step is a spermogram. The ejaculate is tested on three criteria: number of sperm, their motility and shape. Normal values: at least 300 million sperm per millilitre, of which 70% should be motile.

In addition, the vet measures hormone levels in the blood. A low testosterone level often explains fertility problems. An ultrasound examination of the testes reveals structural problems, from inflammation to tumours.

What can I do as a breeder for sperm quality?

The basis is optimal physical condition. Overweight demonstrably reduces sperm quality. Regular exercise and high-quality nutrition with sufficient zinc and vitamin E support sperm production.

Heat harms the testes, so breeding male dogs should have access to cool places in summer. Stress from noise, changes in environment or conflicts with other dogs can impair fertility for weeks.

For valuable breeding male dogs, an annual fertility examination from the 5th year of life is advisable. This way you can detect problems early and counteract them in good time.