The role of melatonin on sperm function as well as its use as antioxidant for sperm conservation is analysed in this review. Melatonin has been included in the cooling/freezing media for the conservation of spermatozoa. Depending on the animal species, the best dose to improve sperm quality and fertile capacity is in the range from 0.01 mM to 3.00 mM. Since the work started on the use of melatonin as antioxidant for the conservation of spermatozoa (2011), a search for references was done on the subject using internet and our university libraries: journals, proceedings, thesis, etc. The search focused on animal spermatozoa, but a collection of papers on human spermatozoa was also carried out.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Objective: To evaluate the effects of low level ultraviolet (UV) radiation on sperm chromatin structure. Methods: The target study was divided into three groups: (i) males with proven fertility (n=40 ) was taken as Group I (control); (ii) Oligoasthenozoospermic (OAT) cases as Group II (n=36); (iii) males with unexplained infertility (MUI) cases (n=42) as Group III. Specific techniques were used to study the impact of UV radiation (Pre and Post UV exposure) on the sperm nuclear DNA viz. Aniline blue staining was for detection of immature chromatin. Chromomycin A3 fluorescence staining was used to determine protamine-DNA dissociation by intense fluorescence of protamine deficient sperm cells and neutral comet assay was for evaluation of DNA fragmentation. Statistical analysis was carried out using Student's t-test (GraphPad Prism Version-6). Level of significance was considered at P<0.05. Results: The data revealed that spermatozoa of OAT and MUI cases when exposed to UV-radiation showed higher percentage of immature sperm compared with normal fertile individuals. Higher percentage of Chromomycin A3 fluorescence in OAT and MUI cases revealed impaired DNA- protamine binding with subsequent DNA fragmentation after exposure to UV. Conclusions: In the present study, sperm chromatin is at higher risk of DNA fragmentation in the infertile (OAT and MUI) cases due to UV irradiation (254 nm). Hence, short duration UV exposure is detrimental to sperm DNA which could affect ensuing generations.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Objective: To investigate the effect of coconut water with a lone concentration and different concentrations of glycerol on chilled and cryopreserved cattle semen characteristics. Methods: Semen was collected from five mature cattle bulls, at weekly intervals for 5 weeks. The ejaculates were pooled and evaluated for dilution processing. Tris citrate egg yolk fructose was used as control treatment for semen, while 50% (V/V) coconut water, 25% (V/V) bi-distilled water and 25% (V/V, 5% anhydrous monosodium citrate) to 20 mL egg yolk and three different concentrations of glycerol (4%, 6% and 8%) were used as coconut water (CW)- glycerol-yolk extenders (CWCG-4, CWCG-6 and CWCG-8). Extended semen was cooled and cryopreserved. Sperm motility%, sperm membrane integrity%, normal acrosome%, live sperm% and total sperm abnormalities% were recorded after equilibrium and after freeze-thawing. Results: The addition of 4% glycerol to coconut water enriched media (CWCG-4) revealed the most effective addition of glycerol on all parameters after equilibrium and after freeze-thawing. Conclusions: Coconut water enriched media with 4% glycerol addition is safe to be used as an extender in bull semen preservation because it is a sterile liquid. So, it can be used without addition of antibiotics to the extender, as antibiotics have to some extent hazardous effect on spermatozoa.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Objective: To analyse the seasonal effect on physiological parameters, reproductive profiles and in vitro fertility in breeding mithun bulls. Methods: A total of ten adult mithun bulls age of 5 to 6 years old with good body condition (score 5-6) were selected from ICAR-NRC on Mithun, Jharnapani, Nagaland, India. The seasons were categorised into winter, spring, summer and autumn seasons based on the meteorological data and sunshine hours. The physiological parameters, reproductive profiles and in vitro fertility parameters were assessed during different seasons in mithun under the semi-intensive system of management. Results: The statistical analysis revealed that these experimental parameters were differed significantly (P<0.05) among the seasons and in overall spring and winter seasons were more beneficial in mithun breeding programme, although, the breeding in mithun occurred throughout the year with variation. Conclusions: It is concluded that collection & preservation of mithun semen and artificial insemination in mithun species during the season of spring and winter has significant beneficial effect in terms of semen production, freezability and fertility for artificial breeding programme in mithun under the semi-intensive system.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Objective: To determine the effects of different concentrations of penicillamine, hypotaurine, and epinephrine (PHE) as well as incubation time on motility, hyperactivity and acrosome reaction (AR) of ram sperm in vitro. Methods: Freshly ejaculated spermatozoa from three ram were collected, pooled and subjected to swim up technique in modified sperm Tyrode's albumin lactate pyruvate medium supplemented with different concentrations of PHE (10, 20, 30, 40, 50, 75 and 100 mM/mL). Then best concentrations were compared and examined for motility, hyperactivity and AR. Results: A high concentrations of PHE (30, 40, 50, 75 and 100mM/mL) showed a significant increase in motility when compared to control immediately after dilution and exist for the first and second hour of incubation period. However, when longer incubation time were used, a significant (P<0.05) decrease in motility was achieved. Similar finding was observed in hyperactivity. Stained semen samples showed a maximum percentage of incomplete AR after 1 h incubation corresponding to 50 and 75 mM/mL of PHE; however, spermatozoa treated with 75 mM/mL had a higher tendency to undergo complete AR after further incubation up to 4 h. A dose dependent relationship was detected where the maximum value of total AR was shown in spermatozoa treated with 75 mM/mL PHE for 4 h. Conclusions: To obtain better motility, hyperactivity and AR, treatment of ram spermatozoa with 75 mM/mL PHE for 4 h before being used in insemination was considered the best concentration of PHE to be used in the process of in-vitro fertilization.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Objective: To express recombinant protein that comprises an important fragment of human sperm specific voltage dependent anion channel 3 (VDAC3) protein as a potential molecule for generation of antibody, which can affect sperm function, aiming at spermicide development. Methods: The produce of VDAC3 recombinant protein encoded by cDNA sequence of human VDAC3 exon 5-8, based on experimental design of VDAC3 knock-out mice study. And after the purification of various human sperm VDAC3 recombinant proteins, epitope has been predicted in our recombinant protein determined by ElliPro program. Polyclonal antibody was produced for 14 wk. Then anti-VDAC3-exon 5-8 recombinant antiserum was inoculated to human sperm. After the process, antibody VDAC3 protein in human sperm was incubation with anti-VDAC3 recombinant antibody. Finally evaluation the effect of VDAC3 antiserum to human sperm motility and plasma membrane integrity was proceeded. Results: Human VDAC3 recombinant protein was successfully over-expressed in Escherichia coli and purified by affinity chromatography method. Purified human sperm VDAC3 recombinant protein could stimulate immune response in rabbit producing an antibody against VDAC3. Anti-VDAC3 recombinant antibody recognized VDAC3 antigen in human sperm could decrease human sperm motility and membrane integrity significantly. Conclusions: Anti-VDAC3 recombinant polyclonal antibody that we produced in rabbit by ourselves could decrease sperm motility and sperm membrane integrity. The authors suggest this polyclonal antibody could be used as a candidate agent for male contraception in the future. Furthermore, the authors intend to explore the effect of this antibody into sperm function aiming at male contraceptive vaccine development.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Objective: To assess the effect of region, season and year of insemination on in-vivo fertility of Italian-Egyptian crossbred buffalo semen. Methods: A total number of 4 799 female buffaloes were inseminated by frozen semen with at least 50% post-thaw motility of Egyptian-Italian crossbred bulls in three localities in Delta, lower Egypt (El-Behira, El-Sharkia and Damietta) during the period of 2013, 2014 and 2015. The pregnancy rate after two months was evaluated during the four seasons. Results: The rate of pregnancy was significantly (P<0.000 1) differ among the three localities. The effect of year of insemination on pregnancy rate was significantly higher during 2014 and 2015 than 2013 in El-Sharkia and El-Behira. But in Damietta, the rate of pregnancy was significantly higher in 2014 than 2013 and 2015. There were no significant differences among seasons in El-Behira and Damietta governorates but there was significant (P<0.05) differences in pregnancy rate in El-Sharkia. It was higher in summer, spring and autumn than in winter. Conclusions: Localities, year of insemination and season of the year have effects on fertility of crossbred Egyptian-Italian buffalo semen.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub]

Objective: To evaluate the impact of freezing–thawing on the human sperm head vacuoles and the potential value of motile sperm organelle morphology examination for selection of frozen-thaw spermatozoa. Methods: In 30 sperm samples from infertile men, analysis for conventional sperm parameters (motility, vitality, and normal morphology) and a morphological analysis at high magnification for vacuoles examination were done before cooling and after warming. For description of sperm head vacuoles, two hundred spermatozoa were examined and were classified into three groups according to presence and vacuole areas including no vacuole group (free of any vacuole), small vacuole group (occupy not more than 4% of the nuclear area), and large vacuole group (occupy more than 4% of the normal nuclear area). Results: Significant reduction of progressive motility and vitality was observed following cryopreservation (P<0.001). Also, normal morphology decreased significantly after cryopreservation (P<0.05). Spermatozoa with a vacuole-free head had a significant reduction in cryopreservation group (P=0.013). The percentage of spermatozoa with small vacuoles increased slightly, but not significantly after cryopreservation (P=0.296). Conclusions: Motile sperm organelle morphology examination is a powerful research tool for investigating spermatozoa abnormalities such as vacuoles that are increased post cryopreservation.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub]