Robert A. Patzner

Determination of semen quality of the rainbow trout, Oncorhynchus mykiss, by sperm motility, seminal plasma parameters, and spermatozoal metabolism

Abstract This study investigated the relationships between semen fertilization capacity and sperm motility, seminal plasma composition and sperm metabolism in the rainbow trout, Oncorhynchus mykiss , to find out biomarkers for semen quality. Variations in semen fertilization rate could be best described by three multiple regression models: Firstly, a model including the seminal plasma pH ( x 1 ), β - d -glucuronidase activity ( x 2 ), total lipid levels ( x 3 ) ( y =894.77 x 1 −53.13 x 1 2 −6.58 x 2 −0.0006 x 1 x 2 −0.62 x 3 +0.008 x 3 2 −3666.19, F -value=10.35, R 2 =0.805, P x 1 ), respiration activity ( x 2 ) aspartate aminotransferase activity ( x 3 ), total lipid levels ( x 4 ) ( y =−2.06 x 1 −1.63 x 2 +0.073 x 1 x 2 −0.049 x 3 +0.029 x 4 +0.0031 x 4 2 +97.96, F -value=12.41, R 2 =0.754, P x 1 ) and total swimming velocity ( x 2 ) ( y =0.44 x 1 −0.38 x 2 +0.011 x 2 2 −0.00006 x 2 3 +32.87, F -value=51.31, R 2 =650, P y =0.72 x +25.99, R 2 =0.594, P y =1460.2 x −89.41 x 2 −5881.2, R 2 =0.525, P y =−1.85 x +84.59, R 2 =0.554, P 80%) is characterised by high sperm motility rate ≥75%, medium sperm swimming velocities of 100–120 μ m/s, optimal seminal fluid protonic composition (pH of 8.0–8.2), balanced energy metabolism (spermatozoal respiratory activity≤5 μ mol/min/100 mg protein, spermatozoal malate dehydrogenase activity≤2.5 μ mol/min/100 mg protein, medium seminal fluid total lipid levels of 20–60 mg/100 ml and spermatozoal total lipid levels of 100–400 μ mol/100 mg protein), and low seminal fluid lytic activity ( β - d -glucuronidase≤0.4 μ mol/min/l [≤0.5 μ mol/min/100 mg protein]).

Motility of spermatozoa ofAlburnus alburnus (Cyprinidae) and its relationship to seminal plasma composition and sperm metabolism.

The composition of seminal plasma and metabolism of sperm of the cyprinid fishAlburnus alburnus were investigated. Statistically significant correlations were found between motility parameters and seminal fluid osmolality, pH, Na+, K+ and protein levels (negative correlations: % immotile spermatozoa-Na+, K+; positive correlations: % motile spermatozoa-osmolality, pH, Na+, K+, protein; % linear motile spermatozoa-pH protein; swimming velocity of spermatozoa-pH, Na+, protein). Spermatozoan motility and ATP metabolism and glycolysis were correlated as indicated by measurement of ATPase, pyruvate kinase, adenylate kinase and lactate dehydrogenase activity. The physiological meanings of these correlations and their possible significance for quality control of semen are discussed.

Changes in Morphology, Physiology, Metabolism, and Fertilization Capacity of Rainbow Trout Semen following Cryopreservation

Abstract Alterations in morphology, physiology, metabolism, and fertilization capacity of the semen of rainbow trout Oncorhynchus mykiss after cryopreservation were investigated. In frozen–thawed semen, only about 10–20% of the spermatozoa had an unchanged structure that was similar to untreated spermatozoa; about 20–40% showed intensive signs of swelling of the head and midpiece regions and of the mitochondria. The remaining spermatozoa were damaged in some way. When compared with spermatozoa in untreated semen, the percentage of immotile spermatozoa in frozen–thawed semen was significantly higher, and the rate of motile spermatozoa was decreased. In fertilization solution, the motility of spermatozoa was mainly circular before cryopreservation and linear after cryopreservation. The swimming velocity of spermatozoa did not differ between untreated and frozen–thawed semen. Activities of adenylate kinase and of pyruvate kinase in untreated semen and frozen–thawed semen did not differ significantly. Activit...

Fine structural changes in spermatozoa of the grayling, Thymallus thymallus (Pisces: Teleostei), during routine cryopreservation

Abstract Spermatozoa of the grayling (Thymallus thymallus) were cryopreserved in liquid nitrogen by several different methods using four different extenders and fertilization rates and fine structural changes were investigated. Morphological damage was observed immediately after dilution in the extenders. After freezing and thawing a marked decrease in semen quality was noted: about 40 to 50% of the spermatozoa were completely damaged, 30 to 40% changed and only 10 to 20% showed an intact morphology. These changes were not prevented by using thawing solutions.

Minireview: The modes of egg attachment in teleost fishes

Abstract Oocytes and eggs from teleost fishes are always surrounded by an egg envelope of variable dimensions. This envelope (zona radiata) in teleosts normally consists of two layers, a zona radiata interna and a zona radiata externa. The chemical composition of the interna is proteinaceous. Neutral and acid mucopolysaccha‐rides are the main components of the externa. The zona radiata interna is largely responsible for a protective function, whereas the zona radiata externa is used to attach the eggs to the substrate where they are deposited. For the latter it is equipped with variable mechanisms such as special sticky layers (e.g., in Phoxinus pboxinus, Chalcalburnus chalcoides mento, Esox sp., Lota lota and 1‐eggs in cichlids), hexagonal patterns (e.g., in many percids and in channichthyids), villi‐like protuberances (= attaching‐plugs; in many cyprinids), attaching‐filaments (e.g., in gobies and blennies, p‐eggs in cichlids, piranhas and clariids), a jelly layer (Perca fluviatilis) or a muco‐follicle ...

Cryopreservation of semen of the grayling (Thymallus thymallus) and the Danube salmon (Hucho hucho)

Abstract Cryopreservation of semen of Thymallus thymallus and of Hucho hucho was investigated with a method that was originally developed for Oncorhynchus mykiss . Assessments of fertilization rate were used to establish the type and concentration of cryoprotectant, freezing rates and thawing conditions for the two species. In both H. hucho and T. thymallus , 10% methanol was the most effective cryoprotectant, followed by a 5% DMSO-1% glycerol mixture, 10% DMSO, 10% n , n -dimethylacetamide and 5% glycerol. Using an open system and 0.5ml straws, freezing of semen was optimal 1.5 cm above the level of liquid nitrogen (at − 110 ± 2 °C) and thawing was best in a 25 °C water bath for 30s. Post-thaw fertilization rates were 90–100% of control with fresh semen at sperm/egg ratios of (1.2–1.6) × 10 6 spermatozoa per egg in T. thymallus and at sperm/egg ratios of (4.3–5.5) × 10 6 spermatozoa per egg in H. hucho .

The seminal vesicles of the male grass goby,Zosterisessor ophiocephalus (Teleostei, Gobiidae)

SummaryThe fine structure of the seminal vesicles ofZosterisessor ophiocephalus, the annual changes during the reproductive cycle, and the composition of the secretion are investigated by electron microscopy and by enzyme, polysaccharide, and protein histochemistry. The seminal vesicles are accessory glands of the male reproductive system which produce sialoglycoproteins during the spawning period. They show a significant annual cycle. During the postspawning period they have a regressive phase, followed by a regeneration phase during interspawning and a proliferation phase during prespawning. Possible functions of the seminal vesicle secretion are discussed.

Habitat Utilization and Depth Distribution of Small Cryptobenthic Fishes (Blenniidae, Gobiesocidae, Gobiidae, Tripterygiidae) in Ibiza (Western Mediterranean Sea)

The paper describes the habitat utilization of small cryptobenthic fishes of the families Blenniidae (Lipophrys nigriceps, and Parablennius zvonimiri), Gobiesocidae (Apletodon incognitus, Gouania wildenowi, Lepadogaster candollei, and L. lepadogaster), Gobiidae (Chromogobius zebratus, Corcyrogobius liechtensteini, Didogobius splechtnai, Gammogobius steinitzi, Millerigobius macrocephalus, Thorogobius ephippiatus, T. macrolepis, and Zebrus zebrus), and Tripterygiidae (Tripterygion melanurus). Nine different habitats from the waterline to a depth of about 40 m were examined. The depth distributions of the single species and co-occurrences with other cryptobenthic fish species are given.

Aging Processes of Rainbow Trout Semen during Storage

Abstract Changes in fertility, motility, sperm metabolism, and seminal plasma composition during 2-h in vitro storage on ice (2 mL semen in a 10-mL centrifuge tube with a diameter of 1 cm) were investigated for semen from rainbow trout Oncorhynchus mykiss. After 2 h, the fertilization capacity was reduced by about 35%, motility rate by 65%, and swimming velocity by 26% in comparison with freshly collected semen. The seminal fluid osmolality and sodium and potassium concentrations decreased, while the spermatozoan sodium and potassium levels increased, indicating ion influx into the cells. The increase in glycerol, fatty acid, and triglyceride levels of the seminal fluid and of the spermatozoa indicated aging of semen. Spermatozoan adenylate kinase, malate dehydrogenase, and respiratory activities, and thus energy requirements of semen, were high after 2-h semen storage compared with fresh semen. Spermatozoa used glucose for energy supply as its levels decreased. Adenosine triphosphate, NADH, and lactate l...

Monosaccharides as energy resources during motility of spermatozoa in Leuciscus cephalus (Cyprinidae, Teleostei).

Spermatozoa of Leuciscus cephalus have the enzymatic outfit for glycolysis but lack lipase, phospholipase and glucosidase activities. Therefore, they are not able to utilize lipids and polysaccharides as energy resources. During motility they use monosaccharides as energy reservoirs: the intracellular glucose, galactose and fructose levels decrease significantly while lactate levels increase.