Dietary n-6:n-3 ratio and Vitamin E improve motility characteristics in association with membrane properties of boar spermatozoa

Composition of Fatty Acids and Localization of SREBP1 and ELOVL2 Genes in Cauda Epididymides of Hu Sheep with Different Fertility

The epididymis is an organ that transports, matures and stores sperm, and has functions such as secretion and absorption. Polyunsaturated fatty acid (PUFA) compositions in sperm membrane were changed during the process of epididymis maturation and influence the male fertility. This study aimed to investigate differences in crude fat and fatty acid content in cauda epididymis between high and low fertility of Hu sheep. One hundred and seventy-nine Hu ram lambs were fed from 56 days to 6 months under the same environment. After the feeding trial, all rams were slaughtered, and the body weight, testicular weight, epididymal weight and sperm density were measured. Pearson correlation analysis showed significantly moderate positive correlation between epididymal weight and sperm density and testicular weight. Eighteen rams were selected and divided into the high fertility group (H, n = 9) and low fertility group (L, n = 9) according to the epididymal weight, sperm density and histomorphology. The crude fat content, fatty acid profile and genes related to fatty acid metabolism were detected. The crude fat content, total fatty acid, total n-3 PUFA and docosahexaenoic acid (C22:6n-3, DHA) content of cauda epididymis in high fertility group was significantly higher than those in low fertility group (p < 0.05). However, the ratio of n-6/n-3 PUFA was significantly lower than that in group L (p < 0.05). Immunohistochemistry results showed that SREBP1 and ELOVL2 were expressed in pseudostratified columnar ciliated epithelium and smooth muscle cells. The mRNA expression of SREBP1 (p = 0.09) and ELOVL2 (p < 0.05) in the high fertility group were increased. In conclusion, the high expression of SREBP1 and ELOVL2 may contribute to high n-3 PUFA content in cauda epididymis of high-fertility Hu sheep.

"Fine feathers make fine birds" - The mammalian sperm plasma membrane lipid composition and effects on assisted reproduction

The sperm plasma membrane is important in modulating many sperm functions. The sperm membrane is composed of a complex mixture of lipids including phospholipids, glycolipids and sterols. There are differences of sperm membrane composition among mammalian species with two groups differing in the most abundant polyunsaturated fatty acid (PUFA), either docosahexaenoic (ω-3 PUFA) or docosapentaenoic acid (ω-6 PUFA). During testicular and epididymal maturation, composition of the sperm plasma membrane evolves with spermatozoa gaining the capacity for fertilization. The importance of fatty acid metabolism for complete spermatogenesis has been elucidated using gene knockout mice. During epididymal transit cholesterol content decreases and PUFA content increases, conferring more fluidity properties to the sperm membrane. The relatively lesser content of antioxidant enzymes and the relatively larger content of PUFA make the spermatozoa particularly susceptible to lipid peroxidation during sperm preservation. In numerous studies, there was adding of PUFA and antioxidants to the diet of animals or to semen extenders with the aim to improve sperm membrane integrity. This review highlights the current knowledge on the sperm membrane composition and effects on sperm function in mammalian domestic animals.

Alginate oligosaccharides increase boar semen quality by affecting gut microbiota and metabolites in blood and sperm

Alginate oligosaccharides (AOS), natural polymers from brown seaweeds (such as Laminaria japonica, Undaria pinnatifida, and Sargassum fusiforme), have been reported to possess many beneficial advantages for health. In the current study, after 9 weeks of dietary supplementation, AOS 10 mg/kg group (AOS 10) group increased boar sperm motility from 87.8% to 93.5%, p < 0.05. Moreover, AOS10 increased the relative abundances of Bifidobacterium, Coprococcus, Butyricicoccus (1.3–2.3-fold; p < 0.05) to increase the beneficial blood and sperm metabolites (1.2–1.6-fold; p < 0.05), and important sperm proteins such as gelsolin, Zn-alpha2 glycoprotein, Cation Channel Sperm-Associated Protein, outer dense fiber of sperm tails, etc. (1.5–2.2-fold; p < 0.05). AOS had a long-term beneficial advantage on boar semen quality by the increase in semen volume (175 vs. 160 ml/ejaculation, p < 0.05). AOS may be used as dietary additives for improving semen quality.

Influence of Fat-Soluble Vitamin Intramuscular Supplementation on Kinematic and Morphometric Sperm Parameters of Boar Ejaculates

Ejaculate quality can be regarded as multifactorial, with nutrition being a factor that could directly influence sperm parameters. The present study aimed to evaluate seminal quality associated with seasonal fat-soluble vitamin supplementation of boars. Seven sexually mature boars were randomly allotted to one of the three groups, and fed one of the three supplementary diets for 32 weeks: (1) control treatment (COD), without supplementation of fat-soluble vitamins, (2) treatment containing 100% fat-soluble vitamin supplementation administered intramuscularly, which was based on fat soluble vitamin supplementation (A, D3, E) (FVD1), and (3) treatment containing 50% of fat-soluble vitamin supplementation (FVD12). Semen was collected at 7-day intervals. Semen samples were analyzed to assess several sperm parameters using the Computer-Assisted Semen Analysis (CASA) ISAS^®v1 system. Results showed that groups receiving FVD1 and FVD12 supplementation had an increased semen volume. The percentages of motile and progressively motile sperm were increased by FVD1 treatment. A statistically significant interaction between treatment and season was found in the percentage of motility and progressive motility (p < 0.05). Sperm concentrations showed significant differences (p < 0.05) between treatments. Velocity variables (VSL, VCL, and VAP) were higher (p < 0.05) in boars that received fat-soluble vitamin supplementation in comparison to controls receiving no supplementation. The FVD1 treatment presented spermatozoa with greater head size and more elongated heads (p < 0.05). Overall, the utilization of dietary fat-soluble vitamin supplementation significantly improved the semen quality of boar ejaculates. This highlights the importance of fat-soluble vitamin supplementation in sexually active boars.

THE EFFECT OF CONSUMING AVOCADO (Persea americana) ON MICE (Mus musculus) SPERM QUALITY

The nutrients such as protein and vitamin are proven to improve the sperm quality. One nutrient rich fruit is avocado round green variety, which contains vitamins A, C and E higher than other varieties. This study aimed to determine the effect of consuming avocado on the mice sperm quality. This experimental study was using a Completely Randomized Design with four treatments, each with eight replications. Avocado dosage treatments were control, 75 % w/v, 100% w/v, and 133% w/v , with the number of mice were 32 age four weeks. Avocado was given three times a day, each 0.5 mL for six weeks besides the main food. The observed response was the sperm quality including number, motility and morphology. Sperm was taken from the epididymis after the mice were killed by cervical dislocation method. Sperm was made a suspension using 0.9% NaCl solution and a smear preparation to observe the sperm morphology while staining with basic stain crystal violet. The sperm quality was observed by Neubauer's counting rooms through a multimedia microscope. Data was analyzed using Kurskal Wallis test for the sperm number and Anova test for motility and morphological responses. The result showed that avocado had a significant influence for reproductive health, particularly for increasing spermatozoa quality, including concentration, motility and morphology of sperm. The higher dose of avocado given the higher quantity and quality of sperm resulted.

Advancing Semen Evaluation Using Lipidomics

Developing a deeper understanding of biological components of sperm is essential to improving cryopreservation techniques and reproductive technologies. To fully ascertain the functional determinants of fertility, lipidomic methods have come to the forefront. Lipidomics is the study of the lipid profile (lipidome) within a cell, tissue, or organism and provides a quantitative analysis of the lipid content in that sample. Sperm cells are composed of various lipids, each with their unique contribution to the overall function of the cell. Lipidomics has already been used to find new and exciting information regarding the fatty acid content of sperm cells from different species. While the applications of lipidomics are rapidly evolving, gaps in the knowledge base remain unresolved. Current limitations of lipidomics studies include the number of available samples to analyze and the total amount of cells within those samples needed to detect changes in the lipid profiles across different subjects. The information obtained through lipidomics research is essential to systems and cellular biology. This review provides a concise analysis of the most recent developments in lipidomic research. This scientific resource is important because these developments can be used to not only combat the reproductive challenges faced when using cryopreserved semen and artificial reproductive technologies in livestock such as cattle, but also other mammals, such as humans or endangered species.

Amelioration effects of n-3, n-6 sources of fatty acids and rosemary leaves powder on the semen parameters, reproductive hormones, and fatty acid analysis of sperm in aged Ross broiler breeder roosters

This study was conducted to evaluate the effects of dietary polyunsaturated fatty acids (PUFA) sources and rosemary leaves powder (RLP) on the semen quality, fatty acid analysis, and some reproductive hormones of senescent broiler breeder roosters. Thirty-five 45-wk-old Ross breeder roosters were randomly divided into 7 groups (5 birds/group), and received following treatments including control group (basal diet), fish oil (2%), corn oil (2%), an equal (50:50%) proportion of fish oil and corn oil (50:50%), fish oil (2%) with 5 g/kg capsulated RLP, corn oil (2%) with 5 g/kg capsulated RLP, and an equal (50:50) proportion of fish oil and corn oil (50:50%) with 5 g/kg capsulated RLP of diet for 60 D, during which time their seminal characteristics were evaluated every 20 D. At the end of the trial (on day 60), semen samples were tested for determination of sperm fatty acid analysis, lipid peroxidation, and some reproductive hormones. Results showed that feeding fish oil and fish/corn oil with RLP was associated with an increase in docosahexaenoic acid (C22:6n-3) and docosatetraenoic acid (C22:4n-6) in sperm. The fish oil diet increased the proportion of n-3 fatty acids in sperm, and as a consequence, the (n-6)/(n-3) ratio also decreased (P < 0.05). RLP (5 g/kg) to the fish and fish/corn-oil (50:50%)-based diet resulted in improvement in sperm concentration, total motility (%), sperm progressive motility (%), membrane integrity, and viability in terms 0 to 60 day trial (P < 0.05). Diets and age interacted to positively affect sperm concentration and sperm membrane integrity. Also this herbal antioxidant decreased the seminal content of malondialdehyde (MDA) significantly (P < 0.05). Testosterone and LH serum levels of reproductive hormones were significantly higher in fish and fish/corn-oil with RPL (50:50%)-based diet than other groups (P < 0.05). It can be concluded that RLP as an antioxidant could remarkably improve the effects of n-3 and n-3/n-6 PUFA on sperm characteristics, seminal MDA, and hormones levels in aged breeder roosters. The susceptibility of semen to lipid peroxidation was increased in chickens fed without RLP. Future studies are needed to disclose the causal mechanisms involved.

The Effect of Dietary Supplementation of Vitamin E, Selenium, Zinc, Folic Acid, and N-3 Polyunsaturated Fatty Acids on Sperm Motility and Membrane Properties in Dogs

Sub-fertility represents a common challenge in canine reproduction. Different protocols, supplementing daily given quantities of micronutrients, were investigated to improve poor sperm concentration and/or function, which represent breeding major constraining factors in the canine species. Little information is available for dogs concerning the effect of a daily supplementation with a complex of vitamin E, zinc, selenium, folic acid, and n-3 polyunsaturated fatty acids (PUFA) on semen quality. Thus, the present study investigated this effect on semen motility and sperm membrane properties. Serial semen analyses from fourteen healthy normospermic dogs, fed with the same commercial diet, were performed on Days 0 (T0), 30 (T30), 60 (T60), and 90 (T90). Seven dogs were randomly included in the treatment (T) group, receiving a supplementation of vitamin E, zinc, selenium, folic acid, n-3 PUFA; and seven other subjects composed the control (C) group. Total Sperm Count (TSC), Computer-Assisted Sperm Analysis (CASA) indexes, mortality, and functional membrane integrity were assessed. The ANOVA compared results between groups and sampling times (p < 0.05). From T60, the supplementation significantly improved TSC, progressive motility, functional membrane integrity, and decreased mortality. Present results lead us to consider ameliorative effects of a two-month healthy diet supplementation on canine spermatozoa. The positive effects of the described balanced integration of micronutrients on sperm motility and prevention of oxidative stress should be considered, especially when decreased seminal parameters may result from inadequate intake, reduced absorption, increased losses or demand, or to attenuate the impact of age.