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Bees are currently artificially inseminated on a large scale for breeding and research purposes. The sperm of bees has a complex and varied structure, and determination of specific morphological defects in it is very difficult. Its comprehensive analysis by inspecting morphology and morphometry is an important tool for improving honey bee lines. The staining technique should interfere with the cells as little as possible while clearly showing the boundaries of the head and other elements. In this study, a comparative analysis of the morphometry of sperm was performed with various techniques for staining drone semen.

The Dag defect is one of the primary morphological defects in sperm correlating with reduced fertility. This defect is found in the spermatozoa of many livestock species. The aim of the study was to assess the morphometry of the heads of normal sperm and sperm with the Dag defect in the semen of Duroc breeding boars.

The aim of this work was to analyse the effect of incubation of a rabbit insemination dose (ID) with dimethyl sulfoxide (DMSO) on reproductive parameters (kindling rate, number of live-born and stillborn kits, and birth weight of kits). The experiments were carried out using two rabbit breeds. Each ejaculate was diluted to a concentration of 40 to 50 million sperm/0.5 ml ID. DMSO was added to the ID in a concentration of 0.5 M. The control ID did not contain any DMSO. Kindling rates obtained from two different breeds (P1, P2) showed minor improvement (+4.36% P1; +4.06% P2) compared to the controls, but without statistically significant differences. The number of live-born kits per litter obtained from breeds P1 and P2 showed minor improvement (P1 +0.61; P2 +0.13) compared to the control groups (p > 0.05). The weight of live-born kits was higher in the experimental groups (+3.85 g P1 = p = 0.001; +1.18 g P2 = p>0.05) than in the control groups. Monitoring of sperm quality indicators (1, 3 and 6 hours incubation) in in vitro conditions (CASA - Computer Assisted Semen Analysis) showed the best results in the control group that was not treated with DMSO. The data obtained in our experiments suggest positive effects of DMSO incubation on reproduction parameters, especially in vivo. [ABSTRACT FROM AUTHOR]

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.

The effects of physical factors such as radiation (electromagnetic, microwave, infrared, laser, UVC, and X-ray) and high temperature, as well as chemical factors (controlled atmosphere) on the level of global DNA cytosine methylation in C. albicans ATCC 10231 cells were investigated. Prolonged exposure to each type of radiation significantly increased the DNA methylation level. In addition, the global methylation level in C. albicans cells increased with the incubation temperature. An increase in the percentage of methylated DNA was also noted in C. albicans cells cultured in an atmosphere with reduced O2. In contrast, in an atmosphere containing more than 3% CO2 and in anaerobic conditions, the DNA methylation level decreased relative to the control. This study showed that prolonged exposure to various types of radiation and high temperature as well as reduced O2 in the atmosphere caused a significant increase in the global DNA methylation level. This is most likely a response protecting DNA against damage, which at the same time can lead to epigenetic disorders, and in consequence can adversely affect the functioning of the organism. [ABSTRACT FROM AUTHOR]

Copyright of Folia Pomeranae Universitatis Technologiae Stetinensis Agricultura Alimentaria Piscaria et Zootechnica is the property of West Pomeranian University of Technology in Szczecin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Scientiarum Polonorum seria Zootechnica is the property of West Pomeranian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Folic acid has multi-faceted effects on the body. Its biological activity ensures genome stability and the normal course of the cell cycle. A deficiency of this acid can lead to serious consequences for health and life. Folic acid is the most oxidized form of folates taken with food. Folic acid is not produced in horses and must be ingested with food. Its bioavailability is also affected by environmental factors. The aim of the study was to analyse the content of folic acid in the blood serum of Polish Konik horses kept in a free-roaming herd system and a stable system. The folic acid concentrations in all horses were within the normal range of reference values for the species. Higher folic acid concentrations were noted in the free-roaming horses. Variation in the content of folic acid in the serum of stabled horses was higher than in the free-roaming horses. The management system was not found to significantly affect the serum content of folic acid in the horses. [ABSTRACT FROM AUTHOR]

Contents: Sperm morphology and morphometry are considered parameters in fertility diagnosis. They are especially important in the case of species for which there is no standard with respect to morphometric sperm parameters. It is then crucial to apply the staining technique that has the least influence on the sperm structure and provides the most detailed image, so as to enable measurements. The aim of the research was to assess the morphometric parameters of rabbit sperm using silver nitrate staining. The staining process revealed a detailed image of the spermatozoon head and tail, thus enabling precise measurements. From these basic morphometric parameters, four additional shape indices characterizing the sperm head were calculated: ellipticity, elongation, roughness and regularity. These parameters more precisely characterize the shape of the sperm head. Silver nitrate staining can be used as an independent technique in assessment of sperm structure or to supplement routine diagnostics. [ABSTRACT FROM AUTHOR]

Sperm cells isolated from the tail of the epididymis and from the semen of the same individuals were analysed. The use of silver nitrate to stain sperm cells isolated from the tail of the epididymis made it possible to identify structures that were not visible in the sperm from semen. Silver nitrate very clearly distinguished the acrosomal and distal parts of the sperm head. Following silver nitrate staining, the sperm isolated from the tail of the epididymis were characterized by dark 'collars' in the distal part of the head. These 'collars' are not visible in the sperm cells isolated from semen. The results of the study indicate differences in the dimensions of sperm isolated from the tail of the epididymis and sperm in semen. Sperm isolated from the tail of the epididymis had smaller heads, despite their longer length, and had longer midpieces and tails than ejaculate sperm. Silver nitrate staining is a simple and fast technique. Silver nitrate makes it possible to identify the acrosome and post‐acrosomal region of the sperm head and to clearly identify the midpiece. Therefore, it can be successfully used to supplement routine techniques for evaluating sperm morphology or as an independent technique. [ABSTRACT FROM AUTHOR]

Recent years have seen increased interest in the influence of bioactive dietary components on human genes and gene expression. A good source of many bioactive substances is the chicken egg. The egg is considered to be an excellent food provided by nature. It is a good source of nutrients such as vitamins A, B2, B6, B12, D, E and K, as well as elements including phosphorus, selenium, iron, zinc, magnesium and calcium. The research material use in this study consisted of eggs from hens kept in two different systems: organic and battery cages. The content of calcium (Ca), magnesium (Mg) and zinc (Zn) was determined in the egg contents – in the yolk and white respectively. The content of elements was determined by atomic absorption spectrometry (AAS) using an AA280 FS spectrometer with the automatic dilution of standards and samples. The eggs from the organically raised hens had a higher calcium, magnesium and zinc content. The greater variation in the Ca, Mg and Zn content in the organic eggs is due to the more individualized feeding system. The rearing system of the hens significantly affects the concentration of elements in the egg. The results of this research indicate that eggs from organic farming systems have a richer chemical composition in terms of the content of nutrients such as calcium, magnesium and zinc compared with eggs obtained from caged hens. Therefore, consumers purchasing eggs should consider the system in which the hens were reared, as eggs can be a valuable source of these elements in the diet. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Copyright of Folia Pomeranae Universitatis Technologiae Stetinensis Agricultura Alimentaria Piscaria et Zootechnica is the property of West Pomeranian University of Technology in Szczecin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Folia Pomeranae Universitatis Technologiae Stetinensis Agricultura Alimentaria Piscaria et Zootechnica is the property of West Pomeranian University of Technology in Szczecin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Folia Pomeranae Universitatis Technologiae Stetinensis Agricultura Alimentaria Piscaria et Zootechnica is the property of West Pomeranian University of Technology in Szczecin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Folia Pomeranae Universitatis Technologiae Stetinensis Agricultura Alimentaria Piscaria et Zootechnica is the property of West Pomeranian University of Technology in Szczecin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Folia Pomeranae Universitatis Technologiae Stetinensis Agricultura Alimentaria Piscaria et Zootechnica is the property of West Pomeranian University of Technology in Szczecin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The sperm cells of the honey bee, like the sperm of most invertebrates, belong to the modified type of spermatozoa. In our own research, differences have been observed in the activity of sperm cells isolated from drones at the beginning and end of the season. On the basis of these observations, research was undertaken to determine whether the changes in drone activity are associated with morphological changes. The sperm cells collected from drones at the beginning of the mating season are longer than the sperm cells from the end of the season. Moreover, sperm cells from the beginning of the season exhibited more intensive rotational motion than those collected at the end of the season. Experimental AgNO3 staining differentiated the sperm head into the acrosomal part (darkly stained) and the distal part (lightly stained). Staining in this manner clearly identifies the sperm nucleus and structurally differentiates the tail. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nucleoli are the product of the activity of nucleolar organizer regions (NOR) in certain chromosomes. Their main functions are the formation of ribosomal subunits from ribosomal protein molecules and the transcription of genes encoding rRNA. Nucleoli are present in the nuclei of nearly all eukaryotic cells because they contain housekeeping genes. The size and number of nucleoli gradually decrease during spermatogenesis. Some of the material originating in the nucleolus probably migrates to the cytoplasm and takes part in the formation of chromatoid bodies (CB). Nucleolus fragmentation and CB assembly take place at the same stage of spermatogenesis. CB are involved in the formation of the acrosome, the migration of mitochondria to the midpiece, and the formation of the sperm tail fibrous sheath. The aim of the study was to characterize the nucleoli in the early prophase of spermatogenesis in the wild boar and the roe deer. The roe deer cells have larger nucleoli and a larger cell nucleus than the wild boar cells. The area of the nucleolus as a percentage of the total area of the nucleus was larger as well. The coefficients of variation for all parameters were higher in the roe deer. In the wild boar cells the nucleoli were mainly regularly shaped. The size of the nucleolus and the nucleus of the spermatocyte is a species-specific trait associated with karyotype and the number of nucleolar organizer regions in a given species. [ABSTRACT FROM AUTHOR]

Sperm morphometry has some value as an indicator of reproductive capacity in males. In laboratory practice a variety of slide-staining methods are used during morphological evaluation of semen to predict male fertility. The aim of this study was to determine the effect of staining of semen using four different techniques on the morphometry of the bull sperm cell. The material for the study consisted of semen collected from test bulls of the Black-and-White variety of Holstein-Friesians. The results obtained in the study indicate differences in the dimensions of bull sperm heads when different slide staining techniques were used. The most similar results for sperm head dimensions were obtained in the case of SpermBlue ® and eosin + gentian violet complex, although statistically significant differences were found between all the staining techniques. Extreme values were noted for the other staining techniques – lowest for the Papanicolaou and highest for silver nitrate, which may indicate more interference in the cell by the reagents used in the staining process. However, silver nitrate staining was best at identifying the structures of the sperm cell. Hence it is difficult to determine which of the staining methods most faithfully reveals the dimensions and shape of the bull sperm. [ABSTRACT FROM AUTHOR]

This study was an attempt to evaluate sperm chromatin structure in the semen of insemination boars. Preparations of semen were stained with acridine orange, aniline blue, and chromomycin A3. Abnormal protamination occurred more frequently in young individuals whose sexual development was not yet complete, but may also be an individual trait. This possibility is important to factor into the decision regarding further exploitation of insemination boars. Thus a precise assessment of abnormalities in the protamination process would seem to be expedient as a tool supplementing morphological and molecular evaluation of semen. Disruptions in nucleoprotein structure can be treated as indicators of the biological value of sperm cells. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

A problem in evaluating the morphology and morphometry of sperm is the lack of standardization of staining techniques. The method of staining and evaluating specimens can significantly affect the results of morphometric measurements. The aim of the study was to determine the effect of two techniques for staining stallion sperm on the morphology and morphometric dimensions of sperm cells and the formation of artefacts. The subject of the study was the sperm of Polish Half Bred stallions, isolated post mortem from the tail of the epididymis. Morphometric measurements were made of the following: length, width, perimeter and surface area of the sperm head, surface area of the acrosome, midpiece length, tail length and total sperm length. Sperm evaluation was expanded to include acrosome coverage, i.e. the surface area of the acrosome as a percentage of the total area of the sperm head, and a characterization of the tail, particularly the midpiece. Tygerberg strict criteria were used to evaluate sperm morphology. The data show that the staining method and the chemical reagents applied have a substantial effect on the dimensions and shape of the stallion sperm. The literature on the subject draws attention to the fact that a staining technique should be established or developed which would enable precise and unambiguous analysis of the morphology and morphometry of human and animal spermatozoa. Moreover, a standard should be developed for preparing specimens for morphological analysis. This would enable comparison of results between laboratories, thus enhancing the value of morphological analyses of sperm in predicting and evaluating fertility. [ABSTRACT FROM AUTHOR]

The study was conducted on spermatozoa of selected farm and free-living animal species, isolated post mortem from the tail of the epididymis, and stained with silver nitrate - AgNO 3. The material was collected from pigs, goats, wild boar, and European roe deer. Twenty morphologically normal spermatozoa randomly selected from each animal and well visible under the microscope, were analysed. The following measurements were considered: head length, width, perimeter and area, acrosome area, mid-piece length, tail length, and overall sperm length. AgNO 3 staining differentiated the acrosomal (light hue) and distal (dark hue) part of the sperm head, and a light-hued mid-piece was visible within the sperm tail. Silver nitrate staining revealed species and variety-related differences, particularly in reference to the sperm head. Clear-cut differentiation within the head and tail area made it possible to perform detailed morphometric measurements of the spermatozoa. [ABSTRACT FROM AUTHOR]

Copyright of European Poultry Science / Archiv für Geflügelkunde is the property of Verlag Eugen Ulmer and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Advances in Hygiene & Experimental Medicine / Postepy Higieny i Medycyny Doswiadczalnej is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The use of AgNO3 staining, commonly applied in cytogenetics to identify nucleolar organizer regions, has made it possible to identify nucleoli in primary spermatocytes. One nucleolus was identified in each analyzed cell. Considerable morphological differentiation of the nucleoli during the prophase of the first meiotic division, particularly in leptotene, unobserved in other farm animal species, was noticed. Dark-hued grain-like structures were found within the disintegrating nucleoli, corresponding approximately or exactly to the number of the nucleolar organizer regions in the domestic cattle karyotype. Dark areas were identified in the selected prometaphase chromosomes. Their number corresponded with the number of active NORs defined in the domestic cattle karyotype. [ABSTRACT FROM AUTHOR]

The article presents a research which evaluates the function of silver nitrate staining for assessing spermatozoon morphology and identifying spermatozoon structure in mammals. It examines the spermatozoa isolated from testes and spermatozoa from the semen by providing a comparison, and further determines the usefulness of the sperm preparations. The significance of a spermatozoon chromatin's structure on fertilization and embryo development is discussed.

Simple Summary: The present study describes a detailed morphometric analysis of the sperm of the blue fox (Alopex lagopus) and silver fox (Vulpes vulpes), together with determination of the shape indices of the sperm head. Staining with silver nitrate enables precise identification of the acrosome and reveals structural details of the sperm tail, so that they can be accurately measured. Statistically significant differences were found for most of the morphometric parameters of the two fox species. The blue fox sperm were generally larger, but the acrosome area and coverage were greater in the silver fox. There are no clear recommendations regarding sperm staining techniques for foxes, and no reference values for morphometric parameters of the sperm of foxes or for canines in general. Staining with silver nitrate for evaluation of the morphometry of fox sperm can be used as an independent technique or an auxiliary technique in routine analysis of canine semen. The results presented in this study are the first such extensive characterization of the sperm morphometry of the blue fox (Alopex lagopus) and silver fox (Vulpes vulpes), as representatives of the family Canidae. Canine spermatozoa, especially the sperm of farmed foxes, are not often described in studies on reproduction. The aim of the study was a detailed comparison of the morphometric dimensions and shape of the sperm of two fox species: silver fox and blue fox. Semen collected from 10 silver foxes and 10 blue foxes was used for the study. The specimens were stained with silver nitrate. Measurements were performed of the length, width, perimeter, and area of the head; the area of the acrosome and its coverage; the length of the midpiece and its coverage; the length of the tail; and the length of the end piece of the tail. In addition, four head shape indices were calculated: ellipticity, elongation, roughness and regularity. The following values for the morphometric parameters and shape indices were obtained for blue fox and silver fox, respectively: head length—6.72 µm and 6.33 µm; head width—4.54.µm and 4.21 µm; head perimeter—18.11 µm and 17.37 µm; head area—21.94 µm2 and 21.11 µm2; acrosome area—11.50 µm2 and 10.92 µm2; midpiece length—12.85 µm and 12.79 µm; tail end piece length—3.44 µm and 3.28 µm; tail length—65.23 µm and 65.09 µm; acrosome coverage—52.43% and 52.83%; midpiece coverage—19.71% and 19.65%; sperm length—71.95 µm and 71.42 µm; ellipticity—1.49 and 1.52; elongation—0.19 and 0.20; roughness—0.84 and 1.88; regularity—1.09 and 0.99. The significance of differences between species was verified by Tukey's test at p ≤ 0.05. Statistically significant differences between species were found for the following parameters: head length, width, perimeter and area; acrosome area; tail, end piece, and total sperm length; roughness and regularity. The differences in the size and shape of sperm can be used to establish reference patterns for fox sperm enabling more accurate species identification. [ABSTRACT FROM AUTHOR]

The basic method for analyzing the degree of DNA fragmentation caused by genotoxic factors is gel electrophoresis of single cells (single cell gel electrophoresis), also called the comet assay. The comet assay enables the analysis of the level of several different DNA modifications. The basic testing procedure has been only slightly modified. This method helps identify single-strand and double-strand DNA cracks, as well as any chemical and enzymatic modifications that can potentially turn into cracks in DNA or chromatids. The comet assay makes it possible to detect DNA damage at the level of single cells. It can be employed in analyses of any tissues which provide cellular suspensions. Analysed cells are submerged in agarose on a microscope slide. DNA is what is left after proteins have been broken down. The slide is then subjected to electrophoresis and stained with a fluorescent dye. A "comet-like" image is obtained. The "head" is the cell fixation site prior to lysis; the "tail" represents damaged DNA fragments. The extent of DNA damage is reflected in the length of the tail and the amount of DNA contained in it. The assay finds research applications in the following fields: genetic toxicology, monitoring of DNA repair following chemotherapy and radiotherapy, ecotoxicology, animal and human nourishment, biomonitoring of genotoxicity, epidemiology and assessment of material deposited in sperm and blood banks.

Lampbrush chromosomes (LBCs) present in bird oocytes are a new model in cytogenetics with particular significance for bird chromosome analysis. The fact that female birds are heterogametic makes it possible to observe both sex chromosomes in the form of decondensed structures typical of lampbrush chromosomes. A change in transcription activity associated with physiological processes in geese prior to and after the reproductive season is reflected in chromosome morphology. Lampbrush chromosomes obtained after the reproductive period have reduced side loops, sites of intensive transcriptional activity. However, noticeable characteristics in the chromosomes include inactive chromomeres. Chiasms, PBs, large side loops (ML) and telomeric loops (T, TLL, and GLL) are structures that undergo degradation latest after the termination of reproduction, and as a result, constitute the basis of identification of individual bivalents in different periods of the cell's transcriptional activity.

The synaptonemal complex (SC) is a protein structure which binds two homologues during prophase of the first meiotic division and assures the correct course of genetic recombination. The demonstration and identification of SCs in European domestic goose Anser anser was the aim of the current research. Standard techniques of SC identification do not allow for an analysis of their molecular structure. In meiotic cells of one-day-old nestlings and 17-week-old geese the haploid number of bivalents, darkly stained kinetochores and subtelomeric regions may be evidence for the presence of SCs. Experimental chromosome staining with the DAPI fluorochrome permitted the observation of the characteristic ladder-like structure of SCs and the course of synapsis formation within homologues from early leptotene to their degradation in late pachytene. The detailed molecular structure of synaptonemal complexes can be analysed with an electron or scanning microscope only. Because the bivalent is a direct result of the complex's presence, in the literature the presence of bivalents is equivalent to the term "synaptonemal complex". However, the bivalent and the SC are two different structures.