Fatty Acid Composition Of Spermatozoa Research Articles

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<0.05). A lower percentage of sperm linoleic and arachidonic acids were recorded in F2G0 and F2G3 groups (P<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<0.05). Significantly lowest sperm concentration overall the experiment was observed in the F2G0 group (P<0.05). Higher testosterone levels and lower malondialdehyde (MDA) content were recorded in F0G3 and F2G3 groups in comparison to the F2G0 (P<0.05). Also, the fertility rate of collected eggs from F0G3 and F2G3 groups was higher compared to F2G0 group (P<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 during high temperature humidity index (THI) period improves sperm quality characteristics, antioxidant status and fatty acid composition of sperm under hot humid sub-tropical climate

Environmental heat stress in sub-tropical climates negatively impacts boar semen production and its quality. The present study aimed to examine the heat stress alleviating effects of dietary linseed oil on semen quality and antioxidant status of boar, in the summer and winter seasons in sub-tropical climate. Six Hampshire crossbreed boars were fed with 90 mL linseed oil (treatment) whereas six boars of the same breed were fed 90 mL vegetable oil (control) for sixteen weeks during both season. Sperm quality was assessed for motility, viability, abnormality, acrosomal integrity, and Hypo-osmotic swelling test (HOST). Sperm velocity attributes were assessed by computer-assisted semen analysis (CASA). Antioxidants (glutathione peroxidase; GPx, catalase; CAT, total antioxidant capacity; TAC and nitric oxide; NO) and lipid peroxidation (malondialdehyde; MDA) were measured in seminal plasma and serum. Gas chromatography-mass spectrometry (GC-MS) was used for the estimation of fatty acid composition of seminal plasma and spermatozoa. Feeding linseed oil to the boars significantly (p < 0.05) improved sperm quality at the fresh stage and after 72 h of liquid storage in both season. There was a significant (p < 0.01) effect of treatment and season on semen quality parameters. Significant boar (p < 0.05) effect was recorded on reaction time, semen volume, sperm abnormality, acrosomal integrity and HOST reactive sperm. There was a significant (p < 0.01) effect of treatment and season on the velocity attributes viz. VAP, VSL, VCL, ALH, BCF and STR%. Linseed oil supplementation significantly (p < 0.01) enhanced antioxidant and lowered MDA levels in serum as well as seminal plasma. The concentration of alpha-linolenic (ALA), arachidonic and docosahexaenoic (DHA) fatty acids were significantly (p < 0.01) increased in seminal plasma and sperm after linseed oil supplementation. In conclusion, linseed oil supplementation to boar during high THI months improved the semen quality parameters viz. semen volume, sperm concentration, and progressive motile sperm, along with enhanced antioxidant capacity.

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.

Lipidomic markers of sperm cryotolerance in cattle

The objective of the current study was to determine the fatty acid composition of sperm from Holstein bulls with different freezability (Good and Poor; n = 12). Fatty acids were extracted from frozen sperm in 1:2 (v/v) chloroform–methanol solvent, fractionated into neutral and polar fractions, and composition determined by gas chromatography–mass spectrometry. Thirty-four fatty acids were quantified and their concentrations and percentages within each lipid fraction were calculated. Overall, saturated fatty acids (SFA) were predominant, accounting for 71 to 80% of fatty acids in neutral and polar lipid factions. There were marked differences in fatty acid composition between the lipid fractions (P < 0.001). The branched chain fatty acid (BCFA) concentration (15 to 18 µg) was almost twice as much as polyunsaturated fatty acids (PUFA) concentration found in the polar lipid fraction (8 to 9 µg; P < 0.001). Sperm with different freezability phenotypes only had a few differences in 22:0, 18:1 cis 9, and 14:0 13-methyl fatty acids (P ≤ 0.011). These results are significant because they reveal key understandings of fatty acid composition of sperm membrane and lay a foundation for the manipulation of membrane integrity, fluidity, and stability to advance the assisted reproductive technologies.

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.

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.

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).

The effect of dietary supplementation of algae rich in docosahexaenoic acid on boar fertility

The objective of this study was to assess the effects of dietary supplementation of a commercial algal product rich in docosahexaenoic acid (DHA) on boar fertility as assessed in vitro and in vivo. Boars were fed one of three experimental diets for 19 weeks: (i) Control (Ctl) diet (n = 31), (ii) Ctl diet plus 75g All-G-Rich per day (n = 31) or (iii) Ctl diet plus 150g All-G-Rich per day (n = 30). Parameters assessed were (i) raw semen quality; volume, sperm concentration, total motility and morphology (ii) liquid semen quality; progressive motility, viability, hypotonic resistance and acrosomal integrity (iii) frozen-thawed semen quality; motility, thermal stress, viability, membrane fluidity and mitochondrial activity (iv) sperm and seminal plasma (SP) fatty acid composition (FAC) (v) total antioxidant capacity (TAC) of SP and (vi) farrowing rates and litter sizes of sows (n = 1158) inseminated with liquid semen. Boars consuming 75g All-G-Rich had a larger semen volume (P < 0.05) and a higher total sperm number (P < 0.01) than the Ctl treatment, however, there was no effect of treatment on any other semen quality parameter (P > 0.05). There was no effect of dietary treatment on the FAC and TAC of SP or on farrowing rate and litter size (P > 0.05). There was an effect of dietary treatment on the FAC of sperm, represented by an 1.72 and 1.60 fold increase in the DHA content for 75 and 150g treatments, respectively, compared to the Ctl treatment. In conclusion, a significant increase in semen volume and total sperm number in boars supplemented 75g All-G-Rich daily, resulted in an increase in production of 3 to 4 more doses per ejaculate, thus, indicating that the feeding regime described within this study has the potential for increasing the output of boar studs.

Fatty acid composition of spermatozoa is associated with BMI and with semen quality.

High body mass index (BMI) is negatively associated with semen quality. In addition, the composition of fatty acids of spermatozoa has been shown to be important for their function. The aim of the study was to examine the association between BMI and the composition of spermatozoa fatty acids in men spanning a broad BMI range. We also analysed the relation between fatty acid composition of spermatozoa and semen characteristics, and the relationship between serum fatty acids and spermatozoa fatty acids. One hundred forty-four men with unknown fertility status were recruited from the general population, from couples with identified female infertility and from morbid obesity centres. Standard semen analysis (WHO) and sperm DNA integrity (DFI) analysis were performed. Fatty acid compositions were assessed by gas chromatography. When adjusted for possible confounders, BMI was negatively associated with levels of sperm docosahexaenoic acid (DHA) (p<0.001) and palmitic acid (p<0.001). The amount of sperm DHA correlated positively with total sperm count (r=0.482), sperm concentration (r=0.469), sperm vitality (r=0.354), progressive sperm motility (r=0.431) and normal sperm morphology (r=0.265). A negative association was seen between DHA levels and DNA fragmentation index (r=-0.247). Levels of spermatozoa palmitic acid correlated positively with total sperm count (r=0.227), while levels of linoleic acid correlated negatively (r=-0.254). When adjusted for possible confounders, only the levels of arachidonic acid showed positive correlation between spermatozoa and serum phospholipids (r=0.262). Changes in the fatty acid composition of spermatozoa could be one of the mechanisms underlying the negative association between BMI and semen quality. The relationship between fatty acids of spermatozoa and serum phospholipids was minor, which indicates that BMI affects fatty acid composition of spermatozoa through regulation of fatty acid metabolism in the testis. The role of dietary intake of fatty acids on the spermatozoa fatty acid composition remains to be elucidated.

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 n-3 fatty acids and α-tocopherol on post-thaw parameters and fatty acid composition of bovine sperm

This study was designed to determine the combined effects of adding source of n-3 fatty acids (FA) and α-tocopherol (vitamin E, VE) to semen extender on freezability and FA composition of Brown Swiss bull sperm. Semen samples were collected from 6 Brown Swiss bulls and pooled. In the first trial, semen was divided into 12 groups including 4 levels of n-3 FA (0, 1, 10, 100 ng ml(-1)) and 3 levels of VE (0. 0.2, 0.4 mM). Motility, viability and fatty acid composition of sperm were measured. The treatment of 10 ng ml(-1) n-3 FA and 0.4 mM VE had the best post-thaw sperm characteristics (P < 0.01). In the second trial, sperm lipid composition of this treatment and control (without FA and VE) was determined. Supplementing n-3 fatty acids during cryopreservation increased docosahexaenoic acid (DHA) and the ratio of n-3 to n-6 FA in sperm before freezing and after thawing. The results suggest that combining the optimal level of n-3 FA (10 ng ml(-1)) with the highest level of VE tested (0.4 mM) in a semen extender changed the membrane lipid composition and improved freezablity of Brown Swiss bull sperm.

Trans–fatty acid levels in sperm are associated with sperm concentration among men from an infertility clinic

We measured the sperm fatty acid composition using gas chromatography in anonymized semen samples of 33 men undergoing infertility evaluation at an academic medical center. Trans-fatty acids were present in human sperm and were related inversely to sperm concentration (r = -0.44).

Mice lacking FABP9/PERF15 develop sperm head abnormalities but are fertile

The male germ cell-specific fatty acid-binding protein 9 (FABP9/PERF15) is the major component of the murine sperm perforatorium and perinuclear theca. Based on its cytoskeletal association and sequence homology to myelin P2 (FABP8), it has been suggested that FABP9 tethers sperm membranes to the underlying cytoskeleton. Furthermore, its upregulation in apoptotic testicular germ cells and its increased phosphorylation status during capacitation suggested multiple important functions for FABP9. Therefore, we investigated specific functions for FABP9 by means of targeted gene disruption in mice. FABP9 −/− mice were viable and fertile. Phenotypic analysis showed that FABP9 −/− mice had significant increases in sperm head abnormalities (~ 8% greater than their WT cohorts); in particular, we observed the reduction or absence of the characteristic structural element known as the “ventral spur” in ~ 10% of FABP9 −/− sperm. However, deficiency of FABP9 affected neither membrane tethering to the perinuclear theca nor the fatty acid composition of sperm. Moreover, epididymal sperm numbers were not affected in FABP9 −/− mice. Therefore, we conclude that FABP9 plays only a minor role in providing the murine sperm head its characteristic shape and is not absolutely required for spermatogenesis or sperm function.

Effect of dietary n-3 fatty acids (fish oils) on boar reproduction and semen quality1

The aim of this study was to evaluate the effects of dietary supplementation with different fish oils (rich in PUFA) vs. hydrogenated animal fat (SFA) on semen production and quality, fatty acid composition, and preservation properties in boars under controlled and commercial conditions. In Exp. 1 (in a research station), 44 boars, allocated to 4 dietary treatments, received daily 2.5 kg of basal diet with a supplement of 1) 62 g of hydrogenated animal fat (AF, n = 12); 2) 60 g of menhaden oil containing 18% docosahexanoic acid (DHA) and 15% eicosapentanoic acid (EPA; MO, n = 11); 3) 60 g of tuna oil containing 33% DHA and 6.5% EPA (TO, n = 11); and 4) 60 g of menhaden oil and 2 mg/kg of biotin (MO+B, n = 10). Biotin is a critical factor in the elongation of PUFA. Semen was collected according to 3 successive phases: phase 1 (twice per week for 4 wk); phase 2 (daily collection for 2 wk); and phase 3 (twice per week for 10 wk). Experiment 2 was conducted in commercial conditions; 222 boars were randomly allocated to AF, MO, and TO treatments. Semen was collected twice weekly over a 6-mo period. All diets were balanced to be iso-energetic and provided an equivalent of 989 mg of vitamin E per day. Classical measurements of sperm quantity and quality were done for both experiments. Experiment 1 showed, after 28 wk of supplementation, a massive transfer of n-3 PUFA into sperm from boars fed fish oil diets (MO and TO). No differences were observed among dietary treatments for libido (P > 0.30), sperm production (P > 0.20), or percentage of motile cell (P > 0.20). Unexpectedly, MO+B diet reduced the percentage of normal sperm compared with the other treatments (P < 0.03). In conclusion, although it modified the fatty acid composition of sperm, supplementation of boars with dietary fish oils, rich in long chain n-3 fatty acids, did not influence semen production or quality postejaculation.

Effects of flaxseed dietary supplementation on sperm quality and on lipid composition of sperm subfractions and prostatic granules in rabbit

Lipids are the main structural/functional components of the sperm, and their composition may undergo a series of modifications in relation to either physiologic events (capacitation and acrosome reaction) and/or diet. The goals of the current study were (1) to investigate whether a flaxseed (FS) dietary supplementation could affect the lipid and fatty acid profile of sperm subfractions and of prostatic granules (PGs) and (2) to evaluate the effects of dietary FS on rabbit buck semen quality. Accordingly, 20 adult New Zealand White rabbits were fed ad libitum a control diet (CO) or a diet supplemented with 5% extruded FS. Integration of diet with FS, as a consequence of the linolenic acid (C18:3n-3; LNA; 56%), increased the dietary n-3/n-6 ratio and resulted in a substantial rearrangement of sperm fatty acid composition at the subcellular level, mainly of polyunsaturated fatty acid (PUFA)n-3 (8.3% vs. 14.3%, P < 0.05). The lipid and fatty acid profiles of sperm tail membrane were the most affected, undergoing the following significant changes: (1) a reduction by half of linoleic acid (C18:2n-6; LA) and docosapentaenoic acid (22:5n-6; DPA), and a reduction of cholesterol (−70%); (2) a concomitant increase of LNA (+65%), docosahexaenoic acid (22:6n-3; DHA; +83%), and of oleic acid (C18:1n-9, +61%). As a consequence, the sperm of FS-fed rabbits had a twice higher n-3/n-6 ratio and phospholipid/cholesterol ratio compared with the control sperm. These changes might have been on the basis of the higher responsiveness to hypo-osmotic solution and, hence, the higher sperm track speed observed for the FS group. Also, the membrane integrity and viability of the LNA-enriched sperm were both improved. On the other hand, the presence of lignans in FS might have accounted for the reduction of sperm cholesterol in the semen of FS-treated rabbits. The responsiveness of sperm to acrosome reaction was not affected by the dietary treatment probably due to supranutritional level of vitamin E and to the higher number of PGs, which are known to play a key role in sperm capacitation. In conclusion, our data showed for the first time that the integration of FS into the rabbit diet may improve sperm quality by modifying the sperm lipid composition and that the sperm subfractions and the PGs respond differently to the FS-induced lipid manipulation.

Effects of dietary n-3 fatty acids on characteristics and lipid composition of ovine sperm

The fatty acid composition of sperm affects the fertilization rate. The objective was to investigate the effects of dietary fish oil (as a source of n-3 fatty acids) on semen quality and sperm fatty acid composition in sheep. Eight Zandi fat-tailed rams were randomly allocated into two groups and fed either a control diet or a diet supplemented with fish oil. Both diets were isocaloric and isonitrogenous and were fed for 13 weeks, starting in the middle of the breeding season. Semen samples were collected weekly and their characteristics evaluated by standard methods, whereas samples collected at the start and end of the study were assessed (gas chromatography) for sperm lipid composition. Mean (±s.e.m.) sperm concentrations (4.3 × 109 ± 1.3 × 108v. 3.9 × 109 ± 1.3 × 108 sperm/ml and percentages of motile (77.25 ± 3.34 v. 60.8 ± 3.34) and progressively motile sperm (74.13 ± 1.69 v. 62.69 ± 1.69) were significantly higher in the fish oil group than control. Dietary fish oil increased the proportion of docosahexaenoic acid (DHA, C22:6 n-3) in sperm fatty acid composition. We concluded that feeding fish oil as a source of n-3 fatty acids attenuated seasonal declines in semen quality in rams, perhaps through increased DHA in sperm.

Sperm fatty acid composition and its relationship with sperm concentration among men attending an infertility clinic

Sperm fatty acid composition and its relationship with sperm concentration among men attending an infertility clinic