Evaluation of spermatogenesis and sperm quality
The andrological laboratory of the Leibniz Institute for Zoo and Wildlife Research offers the evaluation of spermatogenesis and sperm quality by selected methods on a service basis. We also offer scientific advice and assistance to develop new methods for evaluation and (cryo)preservation of semen.
Analysis of spermatogenic activity
To assess sexual maturity, seasonality or problems of (in)fertility we evaluate the sperm production by flowcytometric analysis of the ploidy state of isolated and stained nuclei from fresh or frozen testis tissue (e. g. biopsies). A high proportion of haploid nuclei indicates a high meiotic activity.
Evaluation of testis activity is also performed histologically in fixed testis samples or by determination of testicular spem numbers.
Analysis of sperm quality
Sperm quality essentially determines the success of artificial insemination techniques (e. g. artificial insemination, In vitro fertilisation, ICSI). A comprehensive evaluation of semen quality is also helpful to assess the fertilizing ability of male gametes in vivo.
The following methods are basically available but partly need modifications according to the requirements of newly investigated species.
- Evaluation of sperm morphology
- Computer-assisted measurement of motility parameters: AndroVision (Minitüb, Germany)
- Fluorescence based analysis of sperm properties (viability, membrane intactness, activity of mitochondria) and sperm function (capacitation, induction of acrosome reaction)
Staining of active mitochondria in the main pieces of live sperm from Felis silvestris catus (left), Rhabdomys pumilio (center), Sus scrofa domestica (right) by Rhodamine 123 (bright green), dead cells are stained by propidiumiodide (red)
Non-stained elephant spermatozoa (1) are viable and intact, dead spermatozoa are stained red by propidiumiodide (2, 3), the acrosomal head region of membrane-defect spermatozoa is stained green by FITC-labeled peanut agglutinin (3).