Forms of Male Infertility in Animals
Male infertility in animals refers to the temporary or permanent inability of a male to successfully reproduce, often due to reduced numbers of viable spermatozoa or impaired sexual function.
Nils Lagerlöf divided the forms of infertility in males into three general categories:
- Reduced to complete lack of sexual desire and ability to copulate (Impotentia coeundi) – Refers to the inability or diminished ability of a male to perform mating due to behavioral, neurological, or physical causes.
- Inability or reduced ability to fertilize the ovum due to pathology of the testis, mesonephric duct, and accessory sex glands (Impotentia generandi) – Involves defects in sperm production, transport, or accessory gland function that impair fertility.
- Miscellaneous forms affecting the reproductive organs – Includes a variety of other conditions impacting male reproductive anatomy and function that do not fall under the above two categories.
These above conditions are present in males of all species.
The degree of each condition present in males varies considerably between species, breeds, families and individuals. There are many degrees, from mild to severe in each category of the various forms of infertility.
Sometimes reduced sexual desire and ability to copulate may be associated with reduced fertility and poor quality semen but in most cases of infertility in males the two conditions are not related.
In male animals semen collection is usually possible so that direct measurement of semen quality and other test may be applied to diagnose male infertility.
In examining males for infertility or sterility:
- Accurate breeding and health records on the male and the herd should be obtained and examined.
- Secondly, there should be a careful, painstaking physical examination of the male including the observation of his mating behavior.
- Thirdly, one or more thorough semen examination by a trained veterinarian or qualified laboratory is necessary.
To evaluate the nature of a male’s infertility and sterility so that proper recommendations for therapy, treatment or disposal of the animal may be made.
The prognosis in nearly all forms of infertility or sterility in male animals should be guarded.
