Sperm morphology and morphometry are important parameters in predicting fertility. Sperm are considered to be normal if the shape and size of the head, midpiece and tail fall within the classification for a given species. It is important to select the appropriate technique for staining the semen of a given species, because, as many authors have pointed out, some methods work well for one species but are not suitable for analysing another. The aim of the study was to assess the morphometric parameters of boar sperm following the use of different staining techniques and to verify the hypothesis that the staining technique affects the morphometric parameters of sperm. The staining method was found to significantly affect the dimensions of the boar sperm head. The semen stained by the SpermBlue technique had the closest morphometric sperm head parameters to those of the unstained sperm, so this technique, rather than the routinely used eosin and gentian complex, should be the leading technique in the evaluation of boar sperm morphometry. Silver nitrate staining reveals the structure of the sperm in the most detail; this method can be considered universal, and can be used independently or to supplement routine diagnostics. As the staining technique should interfere as little as possible with the structure of the sperm, while revealing its morphology in as much detail as possible, it is crucial to establish the natural dimensions of the unstained sperm head before determining the optimal technique and its reference values. The recommended or most commonly-used techniques are not always the best options for the staining and analysis of sperm of a given species.

Electrophoretic techniques, used to separate mixtures of electrically charged particles, are widely used in science. One of these techniques, native protein electrophoresis in an agarose gel, is applied in human and veterinary medicine. Changes in the proportions of individual protein fractions correspond to significant changes in the physiology of the body. Although the pattern obtained by electrophoretic separation rarely indicates a specific disease, it provides valuable information for the differential diagnosis. Decades of research on the types of patterns obtained in the case of particular diseases have led to the accumulation of substantial knowledge. The paper presents the available information on this topic. Serum protein electrophoresis is recommended in cases of increased levels of total protein in order to reveal the nature of the process. The basic information which can be obtained from electrophoretic separation includes the immune status of the organism. Both increased antigenic stimulation and immunodeficiency are clearly visible in electropherograms. Moreover, the level of heterogeneity of the corresponding protein fractions can help to distinguish between infectious diseases and cancer - multiple myeloma - the latter producing a homogeneous immunoglobulin fraction. Analysis of other protein fractions helps to detect or confirm an ongoing inflammatory process and provides information regarding liver function. Even when the concentration of total protein is within the reference range, this analysis can be recommended as a basic laboratory test.

Semen was collected from Polish Halfbred stallions. Twenty individuals from 3 to 4 years of age were selected for the study. At least one ejaculate from each stallion was collected and assessed. Sperm morphology was evaluated using Papanicolaou stain, SpermBlue ^® , and a complex of eosin and gentian stain, whereas unstained slides were used as control samples. Morphometric measurements were performed on 100 randomly selected sperm heads in each ejaculate. The length, width, perimeter, and surface area of the sperm head were measured. The frequency of nuclear vacuoles was determined as well. Tygerberg’s strict criteria, which most precisely characterise the sperm head, were used in the morphological evaluation of the sperm. The results obtained indicate that in the case of staining with SpermBlue ^® and with eosin+gentian complex, the morphometry of the sperm head seems to be most similar to that observed in unstained smears. It also seems that neither shrinking nor swelling is uniform in the various staining techniques (Papanicolaou stain). Moreover, it appears that in comparison with unstained sperm, all methods caused the width of the head to increase as a result of swelling.