Ejaculated ram spermatozoa, freed from seminal plasma by a dextran/swim-up procedure and exposed to cold shock, were incubated with proteins analyzed fluorescence markers scanning electron microscopy. Seminal bound the sperm membrane modified functional characteristics of damaged reproducing those live cells. Scanning microscopy showed that dramatic structural damage induced cooling reverted after incubation proteins. Assessment integrity also indicated restoration intact-membrane This...

Abstract: We recently demonstrated the presence of melatonin in ram seminal plasma and differences its concentration this fluid between breeding nonbreeding season. In study, we investigate hypothesis that vitro treatment with affects sperm quality, is reflected fertilization (IVF) results. Semen from nine rams was collected during nonreproductive season treated 1 μ m , 10 n 100 p melatonin. Samples were incubated at 39°C 5% CO 2 motility, viability, capacitation status phosphatidylserine...

Higher temperatures lead to an increase of testicular metabolism that results in spermatic damage. Oxidative stress is the main factor responsible for damage caused by heat stress. The aim this study was evaluate lasting effects on ejaculated sperm and immediate or long‐term epididymal sperm. We observed decrease motility mass sperm, as well percentages showing major minor defects, damaged plasma acrosome membranes, a percentage with high mitochondrial membrane potential treated group until...

The study evaluated the protective effect of seminal plasma (SP) added to freezing extender against cryopreservation injuries boar spermatozoa. Pooled sperm-rich fractions collected from 9 fertile boars were frozen in 0.5-mL straws after being extended a conventional either alone or supplemented with 5% SPs (SP1-SP4) (diluted 1:1, vol/vol, Beltsville Thawing Solution extender) 4 (1-4) known sperm cryosurvival (poor, moderate, and good freezers). Cryopreservation assessed terms postthaw...

Some breeds of sheep are highly seasonal in terms reproductive capability, and these changes regulated by photoperiod melatonin secretion. These affect the performance rams, impairing semen quality modifying hormonal profiles. Also, antioxidant defence systems seem to be modulated secretion, shows variations. The aim this study was investigate presence testosterone ram seminal plasma their variations between breeding non-breeding seasons. In addition, we analyzed possible correlations...

Contents The effect of melatonin implants administered during non‐breeding season in Rasa Aragonesa rams on sperm motility parameters and other reproductive traits was assessed. In a first experiment, two were implanted (with group M), remaining males as control (C). Semen each collected from 1 May to 23 June, twice or three times week, assessed using computer‐assisted analysis system. Melatonin increased the percentage progressive motile spermatozoa, particularly 46–75 days after...

Summary Melatonin is a ubiquitous molecule found in wide range of fluids, one them being ram seminal plasma, which it can reach higher concentrations than those blood, suggesting an extrapineal secretion by the reproductive tract. In order to identify source melatonin we first tried determine whether levels were maintained during day. For this purpose, measured plasma obtained from ejaculates six rams at 6:00 a.m. total darkness, 10:00 and 14:00 p.m. The concentration was ( p < 0.05)...

In the field of assisted reproductive techniques (ART), computer-assisted sperm analysis (CASA) systems have proved their utility and potential for assessing quality, improving prediction fertility a seminal dose. Although most laboratories scientific centers use commercial systems, in recent years certain free open-source alternatives emerged that can reduce costs research groups to face. However, these cannot analyze kinetic responses different stimuli, such as chemotaxis, thermotaxis or...

We have already shown that seminal plasma proteins in the ram can repair cold-shock sperm membrane damage and addition of before treatment prevents injury. In this study, we prove 2 protein bands approximately 14 (P14) 20 (P20) kd isolated from are responsible for protective effect. vitro capacitation (CA) acrosome reaction (AR) modified content both on surface. P20 release began at beginning CA, induction AR accounted an additional proteins; not more than 35% these remained acrosome-reacted...

Summary For successful fertilization, a functionally constituted sperm plasma membrane is necessary, and this clearly dependent on the maturation process. The latter involves series of complex changes which result from sequence events occurring at different points within epididymis. transit time through epididymis can be influenced by external factors such as sexual stimulus ejaculatory frequency. present work was undertaken to determine in ram viability other quality characteristics...

ABSTRACT: In this study, certain enzymes in ram semen involved reactive oxygen species elimination and their changes during the cryopreservation process were characterized order to investigate hypothesis that antioxidant defense system is maintenance of frozen sperm quality. Glutathione reductase (GR), glutathione peroxidase (GPx), superoxide dismutase (SOD) activities quantified samples subjected cooling freezing/thawing processes. addition, distribution on surface due cryoinjury determined...

This work analysed intracellular calcium stores of boar spermatozoa subjected to 'in vitro' capacitation (IVC) and subsequent progesterone-induced acrosome exocytosis (IVAE). Intracellular was through two markers with different physico-chemical properties, Fluo-3 Rhod-5N. Indicative parameters IVC IVAE were also evaluated. located at both the midpiece whole head. Rhod-5N present sperm distribution did not change in any assayed conditions. Induction concomitant an increase head Ca2+ signals....

Abstract: Egg yolk and milk are the 2 major membrane cryoprotectants commonly used in freezing media for long‐term preservation of semen (alone or combination with others). However, recent years, there have been increasing arguments against use egg because risk introducing diseases through cryopreserved semen. In this study, we analyzed protective effect lecithin as an alternative to cryopreservation ram semen, using a range functional markers sperm viability, motility, apoptosis,...

The reproductive seasonality of sheep suggests that melatonin receptors may be present in ram spermatozoa. study confirms the presence MT1 and MT2 receptors. receptor was detected using immunocytochemistry, with four sperm subpopulations identified based on following labelling patterns: (1) one small subpopulation over entire head tail; (2) two main exhibited reactivity at equatorial, post-acrosomal, neck tail regions; (3) another equatorial only; (4) a which staining only tail....

Action of reactive oxygen species, protamination failures and apoptosis are considered the most important etiologies sperm DNA fragmentation. This study evaluated effects induced lipid peroxidation susceptibility on native semen profile identified mechanisms involved in fragmentation testicular antioxidant defense Santa Ines ram samples. Semen was collected from 12 adult rams ( Ovis aries ) performed weekly over a 9-week period. Sperm analysis (motility, mass motility, abnormalities,...

We validate the chlortetracycline (CTC) technique for evaluation of capacitation and acrosome reaction-like changes in ram sperm, carrying out a double estimation status after treatment with lysophosphatidylcholine, using fluorescein isocyanate (FITC)-RCA/ethidium homodimer 1 (EthD-1) CTC/EthD-1. Highly consistent results positive correlation between acrosome-reacted sperm evaluated both techniques were obtained. In this study, we evaluate effects BSA, Ca 2+ , NaHCO 3 cAMP agonists their...

Contents The main scope of this manuscript is to analyse the dynamics mitochondrial activity in boar sperm subjected ‘ vitro ’ capacitation (IVC) and subsequent progesterone‐induced acrosome reaction (IVAR). This was determined after analysis rhythm O 2 consumption concomitant changes mitochondria activity‐specific JC‐1 staining. Results showed that IVC, especially IVAR, with a peak (from 1.61 ± 0.08 nmol /min/10 7 viable at 0 h incubation 2.62 0.12 5 min IVAR induction). These results were...

Incubation of boar spermatozoa in a capacitation medium with oligomycin A, specific inhibitor the F0 component mitochondrial ATP synthase, induced an immediate and almost complete immobilisation cells. Oligomycin A also inhibited ability to achieve feasible vitro (IVC), as measured through IVC-compatible changes motility patterns, tyrosine phosphorylation levels acrosomal p32 protein, membrane fluidity subsequent, progesterone-induced acrosome exocytosis (IVAE). Both inhibitory effects were...