Sperm Fatty Acid Research Articles

Omega 6/Omega 3 Ratio Is High in Individuals with Increased Sperm DNA fragmentation.

An imbalance between omega-6 and omega-3 fatty acids in sperm has been linked with lipid peroxidation and DNA damage in sperm, indicating a possible correlation to fertility potential. This cross-sectional study involved 56 infertile men (aged 25-45), and assessed the relationship between the omega-6 to omega-3 fatty acid ratio in sperm and seminal plasma with sperm DNA fragmentation. Individuals were categorized based on high or low levels of sperm DNA fragmentation according to two tests (TUNEL and SCSA assay less or greater than 10 and 30%, respectively), and their fatty acid composition, as well as sperm functional tests, were analyzed. Results showed that men with high DNA fragmentation exhibited higher percentages of total saturated, monounsaturated, and omega-6 to omega-3 fatty acid ratios in both sperm (P < 0.001) and seminal plasma (P < 0.001) compared to men with low DNA fragmentation. The percentage of sperm lipid peroxidation, and residual histone (P < 0.05) were higher, while the percentage of sperm motility (P < 0.001) was lower in the former compared to the latter group. Moreover, Pearson's correlation revealed positive associations between the omega-6 to omega-3 fatty acid ratio with sperm lipid peroxidation, DNA fragmentation, and residual histones in both sperm and seminal plasma. Overall, these observations suggest that consumption of omega-3 fatty acids may be related to male fertility potential, as it appears that individuals with a high percentage of omega-3 fatty acids have better sperm quality compared to men with a lower omega-3 fatty acid.

Sperm fatty acid composition, semen quality, and reproductive performance of roosters fed diets supplemented with n-3 fatty acids and ginger (Zingiber officinale)

Abstract This study aimed to investigate the effect of dietary n-3 fatty acids and ginger (Zingiber officinale) supplementation on semen quality, sperm fatty acids, and reproductive performance of roosters. Seventy-two roosters (30 weeks old) were randomly allocated into 4 dietary treatments including 1) basal diet as the control group (F0G0), 2) basal diet supplemented with 20 g/kg fish oil (F2G0), 3) basal diet supplemented with 30 g/kg ginger powder (PG) (F0G3), and 4) basal diet supplemented with 20 g/kg fish oil and 30 g/kg ginger powder (F2G3) for 10 consecutive weeks. The levels of sperm linolenic acid, EPA, and DHA were higher in fish oil-fed roosters (P&lt;0.05). A lower percentage of sperm linoleic and arachidonic acids were recorded in F2G0 and F2G3 groups (P&lt;0.05). At 38 weeks of age, a higher sperm volume was found in F0G3 roosters than in the F0G0 and F2G0 groups. From week 34 to the end of the experiment, sperm viability, sperm abnormality, and sperm motility were significantly improved in the GP-fed roosters (F0G3 and F2G3 groups) (P&lt;0.05). Significantly lowest sperm concentration overall the experiment was observed in the F2G0 group (P&lt;0.05). Higher testosterone levels and lower malondialdehyde (MDA) content were recorded in F0G3 and F2G3 groups in comparison to the F2G0 (P&lt;0.05). Also, the fertility rate of collected eggs from F0G3 and F2G3 groups was higher compared to F2G0 group (P&lt;0.05). In conclusion, although the use of fish oil in roosters’ diets alone had a negative effect on some parameters related to reproductive performance, the use of ginger powder alone or along with fish oil improved semen quality and fertility potential.

Linseed oil in boar's diet improved in vivo fertility and antioxidant status.

The reactive oxygen species (ROS) which are produced during storage of boar semen are causing oxidative stress and leads to poor fertility. Also, tropical and sub-tropical weather condition adversely impacts the physicomorphological quality and fertility of boar sperm. The aim of this study was to examine the effects of feeding linseed oil to boar on its seminal attributes, sperm kinetics, biomarkers of antioxidant, fatty acid profile of seminal plasma (SP) and sperm and in vivo fertility. Six Hampshire crossbreed boars were fed with 90 ml linseed oil (LIN) whereas six Hampshire crossbreed boars were fed 90 ml canola oil (CON) for 16 weeks. Sperm quality was evaluated (60 ejaculates for each group; a total of 120 ejaculates) for motility, livability, abnormal morphology, acrosomal membrane integrity, hypo-osmotic swelling test (HOST) and sperm kinetic parameters by computer assisted semen analysis (CASA) at 0h and at 72 h of storage at 17°C. Biomarkers of antioxidant (glutathione peroxidase; GPx, catalase; CAT, total antioxidant capacity; TAC) and malondialdehyde (MDA) were measured in SP and serum. Gas chromatography-mass spectrometry (GC-MS) was used for the estimation of fatty acid composition of SP and sperm. Boars fed with linseed oil had higher semen volume (p < .01) and more total sperm numbers (p < .01). Feeding linseed oil to boar enhanced seminal attributes (p < .05) at 0h as well as at 72 h of storage. Linseed oil feeding (p < .01) improved biomarkers of antioxidants and significantly (p < .01) lowered the lipid peroxidation in serum and SP. Linseed oil feeding (p < .05) increased the proportion of alpha linolenic (ALA), arachidonic and docosahexaenoic (DHA) fatty acids in SP. The ratio of n-6 to n-3 fatty acids in sperm increased significantly (p < .01) in treatment group. Farrowing rate was significantly (p < .05) higher in treatment group. In conclusion, feeding linseed oil to boar improved the in vivo fertility, enhanced antioxidant capacity and increased the DHA content of SP and sperm.

Effect of dietary n-3 fatty acid and rooibos (Aspalathus linearis) supplementation on semen quality, sperm fatty acids and reproductive performance of aged male broiler breeders.

The purpose of this study was to assess the effects of dietary fish oil (FO) and rooibos supplementation on semen quality, fatty acids composition and reproductive performance of aged male broiler breeders. Seventy-two 47-week-old Ross broiler breeder roosters were randomly assigned to a 2 × 3 factorial arrangements to include two FO concentrations (0% and 2%) and 3 rooibos concentrations (0%, 1.5% and 3%) for 13 weeks consecutive. The different diets affected semen parameters significantly (p < 0.05), except for the semen concentration and abnormality of the sperm. The sperm of the FO and 3% rooibos-treated group showed better motility and viability when compared to the other groups (p < 0.05). The susceptibility of semen to lipid peroxidation was increased in roosters fed the rooibos-free diets (p < 0.05), but it was reduced (p < 0.05) when the diet was supplemented with 1.5% and 3% rooibos. In addition, at 64 weeks, the highest concentration of testosterone was observed in the roosters fed a diet that included 2% FO and 3% rooibos (p < 0.05); however, the difference in testosterone levels between Week 52 and Week 64 was not significant (p > 0.05). The fertility rate of collected eggs from the FO and 3% rooibos group was higher (p < 0.05) than that of the other groups at the end of the experiment. In conclusion, dietary inclusion of FO along with rooibos improved seminal quality and reproduction performance in aged roosters.

Levels of L-carnitine in human seminal plasma are associated with sperm fatty acid composition.

The fatty acid composition of spermatozoa has been shown to be important for their function, and L-carnitine is crucial for fatty acid metabolism. Its levels in the seminal plasma positively correlate with semen quality, whereas high body mass index (BMI) is associated with both reduced semen quality and altered sperm fatty acid composition. Here, we examined the associations between free seminal L-carnitine levels and sperm fatty acid composition as well as BMI. Semen samples were collected and analyzed from 128 men with unknown fertility status and with BMI ranging from 19 kg m−2 to 63 kg m−2. Sperm fatty acid composition was assessed by gas chromatography, while free seminal L-carnitine analysis was performed using high-performance liquid chromatography. Multiple linear regression analysis showed a positive correlation of free seminal L-carnitine levels with the amount of sperm palmitic acid (β = 0.21; P = 0.014), docosahexaenoic acid (DHA; β = 0.23; P = 0.007), and total n-3 polyunsaturated fatty acids (β = 0.23; P = 0.008) and a negative correlation of free seminal L-carnitine levels with lignoceric acid (β = −0.29; P = 0.001) and total n-6 polyunsaturated fatty acids (β = −0.24; P = 0.012) when adjusted for covariates. There was no relationship between free seminal L-carnitine levels and BMI. Since free seminal L-carnitine levels are associated with semen quality, the absence of a correlation with BMI suggests that reduced semen quality in obese men is independent of seminal L-carnitine.

The effect of dietary flaxseed supplementation on sperm fatty acid composition, semen quality attributes and some blood parameters in Kurdish ram

دانه کتان منبع غنی از اسید آلفا لینولنیک (امگا3) با خاصیت آنتی اکسیدانی بالا ‌می‌باشد، که ‌می‌تواند در سنتز هورمون‌های جنسی و بهبود کیفیت اسپرم در گونه‌های مختلف نقش داشته باشد. مطالعه حاضر اثرات دانه کتان بر خصوصیات کمی و کیفی اسپرم و برخی پارامترهای خونی را بررسی ‌می‌کند. در این تحقیق که در مدت 12 هفته اجرا گردید 15 راس قوچ نژاد کردی انتخاب و به صورت تصادفی به سه گروه تقسیم شدند. گروه شاهد دریافت کننده جیره پایه و گروه دوم که شامل جیره پایه و 5 درصد دانه کتان و گروه سوم محتوی جیره پایه و 10 درصد دانه بود. نتایج نشان داد که غلظت اسپرم، نسبت اسپرم زنده، تحرک کل و عملکرد غشای پلاسما در تیمار 10 درصد دانه کتان در مقایسه با سایر گروه‌ها بیشتر بود (P<0.05). دانه کتان باعث افزایش درصد اسپرم با آکروزوم نرمال شد (P<0.01). با این حال، درصد اسپرم‌های غیر طبیعی پس از دریافت 10 درصد دانه کتان و در پایان هفته 12 در مقایسه با سایر گروه‌های مربوطه کاهش یافت (P<0.05). نتایج نشان داد که مکمل دانه کتان بر قطر بیضه اثری نداشت اما غلظت تستوسترون پلاسما را در گروه 10 درصد نسبت به گروه شاهد افزایش داد (P <0.05). اثر افزودن مکمل دانه کتان، اثر زمان و اثر متقابل آنها بر فعالیت آنزیم گلوتاتیون پراکسیداز معنی دارنبود. جیره 10 درصد کتان موجب افزایش معنی داری اسید چرب DHA (دوکوزاهگزاانوئیک DHA=Docosahexaenoic acid) در چربی اسپرم شد (P<0.05). نسبت اسیدهای چرب امگا سه به شش افزایش یافته و نیز نسبت اسیدهای چرب اشباع به اسیدهای چرب با چند باند مضاعف در گروه 10 درصد در مقایسه با سایر گروه‌ها کاهش یافت (P<0.05). نتایج نشان داد که افزودن 10 درصد دانه کتان به جیره پایه قوچ‌های کردی در خارج از فصل تولید مثل ‌می‌تواند سبب بهبود کمی و کیفی شاخص‌های ازریابی اسپرم و در نهایت بهبود باروری آنها گردد.

Effect of dietary supplementation of whole flaxseed on sperm traits and sperm fatty acid profile in aged broiler breeder roosters.

The objective of this study was to evaluate the effect of dietary supplementation of whole flaxseed on sperm traits and sperm fatty acid profile in aged broiler breeder roosters. Twelve Ross 308 broiler breeder roosters (age: 52weeks; weight: 4,900±210g) haphazardly allotted to three dietary treatments (each treatment contained four replicates and one bird in each replicate) for six weeks. Treatments were different levels of flaxseed (0% flaxseed [GFL0], 2% flaxseed [GFL2] and 4% flaxseed [GFL4]). The feed intake quadratically decreased (p<.05) with increasing whole flaxseed levels for the period (58 to 60weeks). Sperm traits (semen volume and sperm concentration, sperm total and forward motility, sperm viability and morphology, sperm plasma membrane functionality) were evaluated every two weeks (four times), and sperm fatty acid profile was assessed at the end of the experiment. Semen volume, sperm concentration and sperm morphology were not affected by treatments. On week 60, GFL2 group showed a significantly lower percentage of total and progressive sperm motility and sperm membrane functionality in comparison with the control and GFL4 groups. Also, sperm viability was lower in GFL2 group compared with other groups on week 58 (p<.05). In terms of sperm fatty acid profile, GFL2 group significantly reduced the percentage of linoleic acid (C18:2 [n-6]) in comparison with other groups. However, any of the other fatty acids were not affected by dietary flaxseed. In conclusion, dietary supplementation of whole flaxseed could not improve the quality of aged broiler breeder roosters' sperm in this study, nor it could alter the sperm fatty acid profile; thus, it seems necessary to use some antioxidants such as vitamin E in the diet of aged broiler breeder roosters, when supplementing the diets with oils or oilseeds such as flaxseed.

Relevance of Fatty Acids to Sperm Maturation and Quality.

Almost 50% of infertility cases are associated with human male infertility. The sperm membrane is a key structure influencing sperm morphology and function in normal and pathological conditions. The fatty acid profile determines the performance not only of sperm motility but also of acrosomal reaction and sperm-oocyte fusion. This review presents available knowledge on the role of fatty acid composition in human sperm and spermatogenesis and discusses the influence of dietary fatty acids on the sperm fatty acid profile. Recent studies in biological sciences and clinical researches in this field are also reported. The topic object of this review has potential application in medicine by identifying potential causes of infertility.

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.

Effects of Diets Enriched in Linseed and Fish Oil on the Expression Pattern of Toll-Like Receptors 4 and Proinflammatory Cytokines on Gonadal Axis and Reproductive Organs in Rabbit Buck.

Infections of the genital tract can perturb the fertility in humans and animals. Pathogen recognition and activation of innate immunity onset through the pattern recognition receptor activation, such as Toll-like receptor 4 (TLR4), leading to the production of proinflammatory cytokines and mediators. TLR4 is expressed both on leukocytes and nonimmune cells. Rabbit TLR4 shows great similarity to its human counterpart. Moreover, the TLR4 signalling pathway could be modulated by long-chain polyunsaturated fatty acids (LC-PUFA). The objectives of this study were (i) to determine the expression levels of TLR4 and proinflammatory cytokines in the reproductive hypothalamic-gonadal axis of the male rabbit and (ii) to evaluate if the n-3 PUFA-enriched diets can modify their expression levels in the tissues and LC-PUFA profiles in seminal plasma. Fifteen rabbit bucks (n = 5/experimental group) were fed with different diets: commercial standard (group C), rich in extruded linseed (10%, group L), and in fish oil (3%, group FO) for 110 days. TLR4, TNF-α, and IL-1β mRNA were ubiquitously expressed throughout the hypothalamic-gonadal axis. However, TLR4 mRNA expression was lower in the hypothalamus than the epididymis (P < 0.01), seminal vesicles (P < 0.01), and pituitary gland (P < 0.05). Dietary enrichment in PUFA did not modify the gene expression profile nor the histological characteristics of the tissues. Conversely in seminal plasma, rabbits fed with L and FO had lower n-6 (P < 0.05), LC-PUFA n-6 (P < 0.05), and n-6/n-3 ratio (P < 0.05) but higher n-3 (P < 0.001) and LC-PUFA n-3 (P < 0.01) compared to the control group. Our study builds a map of the gene expression of TRL4 and proinflammatory cytokines in the reproductive hypothalamic-gonadal axis of the male rabbit, fundamental step for understanding the immune defence mechanisms. Diets enriched in LC-PUFA did not affect basal gene expression but modulated sperm fatty acid composition. Finally, rabbit may be an excellent animal model to study the relationship between inflammation and infertility, and the nutritional modulation of immune functions.

Decreased very long chain polyunsaturated fatty acids in sperm correlates with sperm quantity and quality.

To determine if levels of very long chain polyunsaturated fatty acids (VLC-PUFA; ≥ 28 carbons;4-6 double bonds) in human sperm correlate with sperm quantity and quality as determined by a complete semen analysis. Ejaculates from 70 men underwent a complete semen analysis, which included volume, count, motility, progression, agglutination, viscosity, morphology, and pH. For lipid analysis, sperm were pelleted to remove the semen. Lipids were extracted from the cell pellet and methyl esters of total lipids analyzed by gas chromatography. The sphingolipids were enriched and sphingomyelin (SM) species measured using tandem mass spectrometry. Pair-wise Pearson correlation and linear regression analysis compared percent VLC-PUFA-SM and percent docosahexaenoic acid (DHA) to results from the semen analysis. VLC-PUFA-SM species having 28-34 carbon fatty acids were detected in sperm samples, with 28 and 30 carbon VLC-PUFA as most the abundant. The sum of all VLC-PUFA-SM species comprised 0 to 6.1% of the overall SM pool (mean 2.1%). Pair-wise Pearson analyses showed that lower levels of VLC-PUFA-SM positively correlated with lower total motile count (0.68) and lower total count (0.67). Total VLC-PUFA-SM and mole % DHA (22:6n3) were not strongly correlated (- 0.24). Linear regression analysis confirmed these findings. This study revealed a positive correlation between the levels of VLC-PUFA with sperm count and total motile count and suggests that both sperm quality and quantity may depend on the presence of VLC-PUFA. The lack of correlation between VLC-PUFA and DHA suggests that low VLC-PUFA levels do not result from inadequate PUFA precursors.

Modification of sperm fatty acid composition during epididymal maturation in bats.

Biochemical properties of polyunsaturated fatty acids (PUFAs) are fundamental to sperm movements. Amongst all adjustments operated during epididymal maturation, sperm membrane lipid composition is remodelled. Specifically, the proportion of PUFAs usually increases from the caput towards the cauda epididymidis. In mammals, PUFAs are predominantly acquired through the diet, which can consequently impact male fertility. We aimed at analysing to what extent n-6 and n-3 PUFAs are incorporated into sperm in the Seba's short-tailed bat (Carollia perspicillata), and at demonstrating the effect of the sperm fatty acid composition on sperm mobility. We therefore provided food varying in fatty acid composition to males of C. perspicillata and measured the fatty acid composition and mobility traits in spermatozoa collected from the caput and cauda epididymides. We found that n-6 and n-3 PUFAs and saturated fatty acids were significantly related to sperm velocity but not to the proportion of progressive sperm (i.e. motility). Concomitant to an increase in sperm velocity, the level of fatty acid saturation increased from the caput to the cauda epididymidis, while the proportion of PUFAs remained similar along the epididymis. A reduction in n-6 PUFAs counterbalanced an increase in n-3 PUFAs. The food treatments did not affect the sperm fatty acid composition. Our results suggest that a precise endogenous control rather than dietary effects determines sperm fatty acid composition in C. perspicillata.

Improvements in semen quality, sperm fatty acids, and reproductive performance in aged Ross breeder roosters fed a diet supplemented with a moderate ratio of n-3: n-6 fatty acids.

The purpose of this study was to evaluate the effects of dietary n-3: n-6 fatty acid (FA) ratios and vitamin E (vitE) on the semen quality, FA composition, hormonal responses, and reproductive performance of aged roosters. Thirty-six Ross broiler breeder roosters were assigned to a 3 × 2 factorial design with 3 n-3: n-6 FA ratios (0.09, 0.16, and 0.23) based on the inclusion of 3 oil sources (canola, canola/fish, and fish) and 2 vitE levels (0 and 200mg/kg). During the 60 d of treatment, semen parameters, FAs composition of sperm, lipid peroxidation, and hormonal responses were monitored. Reproductive performance using artificial insemination was also evaluated at the end of experiment (on day 60). Results showed that the 0.16 and 0.23 dietary ratios increased docosahexaenoic acid and n-3 polyunsaturated FA and decreased docosatetraenoic acid and arachidonic acid in rooster sperm (P<0.05). The 0.16 dietary ratio supplemented with 200mg vitE improved total sperm motility (P<0.05) than the 0.09 and 0.23 ratios, both with and without vitE. Progressive motility, membrane functionality, and viability were significantly (P<0.05) improved in the 0.16 and 0.23 ratios supplemented with vitE. The highest concentration of testosterone was observed in the roosters fed a diet ratio of 0.16 (P<0.05). Compared with no supplementation of vitE, 200mg/kg vitE reduced the lipid peroxidation of rooster sperm (P<0.05). In the artificial insemination, the higher significant percentage of fertility rate (P=0.02) was observed in the 0.16 ratio group that was supplemented with vitE compared to other groups. It can be concluded that supplementation of aged roosters' diet with 0.16 ratio of n-3: n-6 can be a beneficial strategy for improvement of their fertility.

Very long chain polyunsaturated fatty acids in sperm are not associated with sperm progression or morphology

Very long chain polyunsaturated fatty acids in sperm are not associated with sperm progression or morphology

Seasonal changes in the sperm fatty acid composition of Shetland pony stallions

Spermatozoa contain polyunsaturated fatty acids (PUFA). Cryopreservation damages sperm membranes and they become less functional after thawing. We analysed the lipid composition of spermatozoa from Shetland stallions (n = 15) collected monthly from January to June and hypothesized that sperm lipid patterns change with season. In addition, one ejaculate per month was submitted to cryopreservation. Content of saturated palmytic and stearic acid decreased from January to March (p < 0.001) while content of the PUFA docosapentaenoic (p < 0.001) and arachidonic acid (p < 0.05) and total PUFA (p < 0.001) increased. Docosapentaenoic acid was the predominant PUFA in stallion spermatozoa. In conclusion, the sperm fatty acid composition of Shetland pony stallions undergoes seasonal changes, and PUFA content increases from the non-breeding to the breeding season. Seasonal differences in sperm fatty acids might in part explain seasonal differences in the resistance of equine spermatozoa to cryopreservation and cooled-storage.

Chrysin-induced sperm parameters and fatty acid profile changes improve reproductive performance of roosters

Having antioxidant and androgenic effects, Chrysin was orally administrated to roosters and reproductive performance including sperm quality and fatty acid composition, testis index, fertility and hatchability rates as well as blood testosterone concentration were assessed. Twenty eight 40-week-old Ross 308 roosters were individually housed, equally divided into four groups and received different levels of capsulated Chrysin including 0 (Ch0), 25 (Ch25), 50 (Ch50) or 75 (Ch75) mg/bird/day for 12 consecutive weeks. Body weighting as well as semen and blood sampling were weekly done from 1st-10th weeks. A total of three artificial inseminations were carried out on the last two weeks of trial and collected eggs following second insemination were allotted to evaluate fertility and hatchability rates. Sperm fatty acid composition was determined using samples from 12th week. At the end of experiment (12th week) all roosters sacrificed, testis were carefully removed and testis index was calculated. Except for body weight, testis index, sperm abnormality percentage and ejaculated volume, other traits were significantly affected by Chrysin treatment. Sperm total and forward motility, plasma membrane integrity and functionality, semen concentration as well as fertility and hatchability rates were significantly higher in both Ch50 and Ch75 groups compared to control group. In spite of an increasing trend in most of n-3 and n-6 fatty acids, the n-6/n-3 ratio was significantly decreased in both Ch50 and Ch75 compared to other groups. Malondialdehyde concentration was also significantly decreased in Chrysin treated groups compared to control group. Blood testosterone level was only significantly higher in Ch75 group than that other groups. In conclusion, Chrysin administration particularly at higher levels alleviates post-peak fertility reduction in roosters; however, further research are needed to disclose involved mechanism(s).

Effect of omega-3 and omega-6 polyunsaturated fatty acid enriched diet on plasma IGF-1 and testosterone concentration, puberty and semen quality in male buffalo

The objective of the present study was to evaluate the effect of omega-3 and omega-6 PUFA enriched diet on plasma IGF-1 and testosterone concentrations, puberty, sperm fatty acid profile and semen quality in male buffalo. Eighteen male buffalo calves were distributed randomly in three different groups and fed concentrate mixture along with green fodder and wheat straw in 50:40:10 ratios as per requirements. Basis ration of animals in group I was supplemented with 4% of prilled fat (PFA), while in group II and group III were added 4.67% of Calcium salt from Soybean (CaSFA) and Linseed oil (CaLFA), respectively. Male buffalo fed omega-3 PUFA high diet significantly increased concentrations of IGF-1 and testosterone in plasma as compared to two other diets (p<0.05). The age of puberty and scrotal circumference significantly increased by dietary fat effect (p<0.05) of which n-3 PUFA enriched diet (CaLFA) had the largest influence as compared to other diets (PFA and CaSFA). Feeding of n-3 PUFA rich diet significantly increased the DHA (C22:6n-3) content in sperm (p<0.05), which contributed to increased fluidity of plasma membrane, elevated quality of sperm (motility, viability) and in vitro fertility (plasma membrane integrity, acrosome integrity) in both fresh and post-thawing semen. These findings indicate that feeding of n-3 PUFA enriched diet increased IGF-1 and testosterone secretion, reduced pubertal age and improved both fresh and post-thawing semen quality in male buffalo.

Remodeling of Gamete Membrane during Mammalian Fertilization

Fertilization is a central event in the life of sexual organisms. It guarantees the survival of species. Close to the oocyte, the spermatozoon still has to interact with the oolemma. For the mammals, the fertilization process is almost doomed to fail without the GPI-AP Juno on the oocyte and the Immunoglobulin-Super Family protein Izumo on the spermatozoon. Nevertheless, the central question about how membranes merge is none answered. Our study aims a better understanding of the membrane dynamics triggered by the adhesion of a sperm on the oocyte membrane leading to gamete fusion.To do so, we developed two novel approaches. The first one consists in generating a biomimetic pure lipids sperm membrane to measure the fusogenic capacity of the sperm's fatty acids. We found that Nature's wisdom minimizes the spermatozoon's Energy requirement to fuse with standard plasma membrane, compared to other kind of cell lipids composition. Then, incorporating Izumo, we noticed an accommodating oligomerization of this essential protein correlated with the type of lipids. For the second approach, we developed a microfluidic tool to induce a physiological gamete interaction, controlling the time and area of the gamete encounter. This original device offers, in live and full resolution, unique point of view to study live membrane remodeling. We could demonstrate the simultaneity of membrane fusion and spermatozoon internalization as well as a particular way of swimming that seems to be common to sperm which manage to fertilize. These new biophysical tools provide an insight of the dynamics of gamete interplay. They set in motion the usually static biological description of this interaction.

Dietary n-3 PUFAs improve fresh and post-thaw semen quality in Holstein bulls via alteration of sperm fatty acid composition

The goal of this study was to investigate the effect of fish oil–supplemented diet on fresh and post-thaw semen quality and sperm lipid composition in bulls. Bulls were randomly assigned to two groups (n = 6). Six bulls were used as the control group and six received the fish oil (1.2% dry matter of total diet) for 11 weeks. Semen was individually collected from each bull and frozen biweekly. Semen volume, sperm concentration, viability, progressive motility, and fatty acid profile of sperm were measured in 1st, 3rd, 5th, 7th, 9th, and 11th week of experiment. Viability, progressive motility, and fatty acid profile of post-thaw sperm were also measured in 3rd, 5th, 9th, and 11th week of experiment. Data were analyzed with using Proc GLM or MIXED (for repeated measurement data) in SAS program. The fish oil–supplemented diet increased the semen volume and sperm concentration. The fish oil–supplemented diet also altered the viability, progressive motility, and fatty acid profile of fresh and post-thaw sperm. In conclusion, feeding a fish oil–enriched diet via alteration of fatty acid profile of sperm lipid could improve in vitro quality of fresh and post-thaw sperm in Holstein bulls.

Effect of dietary vitamin E on the sperm quality of turbot (Scophthalmus maximus)

A 3-month feeding experiment was conducted in an in-door seawater system to investigate the effect of dietary vitamin E (Ve) on the sperm quality of turbot (Scophthalmus maximus). D-α-tocopherol acetate was supplemented to the basal (control) diet (65.14 mg kg−1 Ve) to obtain low and high levels of dietary Ve (244.60 mg kg−1, LVe; 721.60 mg kg−1, HVe). Compared with the control, sperm concentration was significantly increased in Ve-supplemented groups (LVe and HVe); while relative sperm volume and testis-somatic index were significantly increased in group HVe only. Sperm motility duration was significantly longer in group HVe than in the control, but no significant difference was observed in percent motility among groups. Sperm size, the uniformity of mitochondrial size, and the integrity of mitochondria cristae and plasma membrane were improved by dietary Ve, especially in HVe. The content of Ve in testis and liver as well as polyunsaturated fatty acids in sperm increased with dietary Ve. These results suggested that dietary Ve, especially at the high level (721.60 mg kg−1), significantly improved sperm concentration and motility duration and maintained normal sperm morphology of turbot.