Evaluation of the effect of lecithin and nanolecithin in repairing membrane damage, maintaining membrane integrity, and improving human sperm function in the freezing-thawing process.

PURPOSE: Our study aimed to evaluate the effects of lecithin nanoparticles on sperm quality during cryopreservation. METHODS: In phase one, sperm-freezing media were prepared with lecithin concentrations (0.5%, 1%, and 2%) and lecithin nanoparticles of various sizes (50-100, 100-200, and ≥ 200 nm). Post-thaw, sperm motility, viability, mitochondrial membrane potential (MMP), lipid peroxidation (measured by malondialdehyde, MDA), and DNA fragmentation were evaluated. In phase two, the acrosomal reaction was assessed in the best and worst-performing groups from phase one. DiI labeling detected interactions between lecithin nanoparticles and the sperm membrane. Field emission scanning electron microscopy (FESEM) examined the sperm membrane's surface structure and lecithin binding sites. Atomic force microscopy (AFM) assessed height differences in the sperm surface layer in the best-performing group from phase one. RESULTS: The group treated with 1% lecithin nanoparticles (50-100 nm) showed significantly increased viability post-thaw compared to other groups, with reduced DNA fragmentation and MDA levels. While motility significantly decreased in all groups compared to before freezing levels, lower concentrations, and smaller particle sizes yielded better results. MMP also significantly decreased across all groups with no significant differences. The acrosomal reaction significantly decreased with 1% lecithin nanoparticles (50-100 nm) compared to the 2% (≥ 200 nm) group. DiI-labeled nanoparticles and FESEM revealed that lecithin nanoparticles primarily bound to and infiltrated the sperm membrane, particularly in the head and postacrosomal regions. CONCLUSIONS: Lecithin nanoparticles effectively bind to the sperm membrane, protecting it during the freeze-thaw process and improving sperm viability.

A soy lecithin nanoparticles-based extender effectively cryopreserves Holstein bull sperm.

Plant-based semen extenders, typically derived from soybean lecithin, are easier to modulate more and consistent in their composition than animal-based extenders. As large lecithin particles can, however, reduce effectiveness and solubility in bull semen extenders, sonication was used to create nano-lecithin (NL) particles of soybean lecithin. The objective was to determine the effects of lecithin type and concentration on the quality of frozen-thawed bovine sperm. We hypothesized that reducing the size of lecithin improves its interactions with the sperm and enhances the parameters that favor its motility, viability and fertility. Semen was collected from six mature Holstein bulls and ejaculates meeting minimum standards were pooled. Eight Tris-based extenders that contained 1, 2, 3, or 4 % of either conventional lecithin (L1-L4) or NL (NL1-NL4), plus two control extenders (one animal-based extender containing 20 % egg yolk [EY] and a commercial lecithin-based extender [BioXcell®]) were compared. Among soybean lecithin-based extenders, NL3 had the highest total and progressive sperm motility, and average path, straight-line and curvilinear sperm velocity, and was comparable to EY. Additionally, sperm mitochondrial activity was the highest in NL3, whereas sperm viability was highest in EY, NL3, and L4. Following in vitro fertilization of in vitro-matured bovine oocyes, NL3 had cleavage and hatching rates comparable to BioXcell®, but a lower blastocyst rate than EY. Overall, NL3 performed better than the other extenders for most end points, with efficiency comparable to EY. We, therefore, concluded that reducing lecithin particle size to a nano level improves sperm cryopreservation with optimal performance with 3 % NL.

Rumen-protected glucose hastens uterine involution and increases numbers of ovarian follicles in early post-partum dairy cows.

The primary objectives were to investigate the effects of feeding a new rumen-protected glucose (RPG) on uterine involution and ovarian follicular dynamics in recently calved dairy cattle. From 4 to 30 days after calving, 16 Holsteins (first to third lactation, mean parity 1.75) were randomly assigned to be fed either a basal diet top-dressed with either 600 g RPG (RPG group) or 600 g of the coating material and glucose (CONT group). Based on transrectal ultrasonography, conducted every 3 days starting 20 days after calving, the interval from calving to complete uterine involution was shorter in RPG versus CONT (27.1 vs. 30.4 days, p < .01). Furthermore, based on transrectal ultrasonography conducted every 2 days, cattle fed RPG had smaller (3.0-4.9 mm) ovarian follicles (2.96 vs. 0.9, p < .001) and more total follicles (5.26 vs. 2.85, p < .01). Feeding RPG had increased serum insulin concentrations (4.59 ± 0.54 vs. 3.13 ± 0.57, p < .05), but had no significant effects on serum glucose concentrations, dry matter intake or milk yield. In conclusion, we inferred that cattle fed RPG had increased glucose turnover that was responsible for higher insulin concentrations, faster uterine involution, and more ovarian follicles.

Determining the Optimal Dosage of Lecithin Nanoliposome in Rooster Semen Freezing Medium and Fertility Potential.

Introduction: Lecithin nanoliposome (nano-LPO), with its cryoprotective properties, is considered to enhance the performance of a traditional semen cryoprotectant. Objective: To determine the optimal dose of lecithin nano-LPO added to the rooster semen extender. Materials and Methods: Semen samples collected weekly from eight broiler breeder roosters were mixed and aliquoted into five equal subsamples, during the five successive weeks. The subsamples were then diluted with a semen extender containing 0%, 0.5%, 1%, 1.5%, or 2% of lecithin nano-LPO. Post-thawed semen quality attributes, including sperm motility and velocity parameters, plasma membrane functionality, mitochondrial membrane potential (MMP), apoptosis-like changes, and fertility potential, were evaluated. Results: Total motility and velocity parameters, including curvilinear velocity (VCL), straight-line velocity (VSL), average path velocity µm/s (VAP), straightness (STR), linearity (LIN), lateral head displacement (ALH), and wobble (WOB) were quadratically (p < 0.01) influenced by graded levels of lecithin nano-LPO, such that the highest values were obtained when 1% of lecithin nano-LPO was used. Treatments had no significant effect on plasma membrane functionality; however, MMP (p < 0.08) and percentages of live and dead spermatozoa (p < 0.05) quadratically responded to increasing levels of lecithin nano-LPO, where the best outcome was found when about 1% of lecithin nano-LPO was used in the semen extender. The percentage of apoptotic spermatozoa cubically responded to increasing levels of lecithin nano-LPO (p ≤ 0.07). No significant trend of fertility rate was found in response to addition of lecithin nano-LPO levels. Conclusions: Supplementing an extender with 1.10% of lecithin nano-LPO is shown to be the optimal dose associated with the most improvement in post-thawed rooster sperm velocity measurements.

Supplementation of freezing medium with encapsulated or free glutathione during cryopreservation of bull sperm.

The objective was to compare effects of encapsulated or free glutathione (GSH) on the quality of frozen-thawed bull sperm. Ejaculates were collected via artificial vagina from six mature Holstein bulls once weekly for 6 weeks. All ejaculates had motility ≥70%, sperm concentration ≥1.0 × 109 /ml and ≤15% morphologically abnormal sperm. Each week, semen was pooled and diluted with lecithin-based extenders containing various concentrations of encapsulated (E0, E1, E2.5 and E5 mM) or free (F0, F1, F2.5 and F5 mM) GSH, with total glutathione content determined before and after cryopreservation. Total GSH in fresh semen was (mean+SEM) 4.8 ± 0.2 nmol/108 sperm, whereas in frozen-thawed semen of group F0 (control), it decreased to 1.4 ± 0.2 nmol/108 sperm, a 70.8% reduction (p < .05). In addition, total GSH in frozen-thawed semen from groups E2.5, E5 and F5 were 2.4 ± 0.2, 2.8 ± 0.2 and 1.8 ± 0.2 nmol/108 sperm, respectively (E5 versus. F0, p < .05). Compared to group F0, frozen-thawed sperm from group E2.5 had greater (p < .05) percentages of sperm that were viable (Annexin-V) (61.1 ± 1.8 versus. 71.1 ± 1.8) and that had cell membrane integrity (eosin-nigrosin) (64.5 ± 3.1 versus. 80.0 ± 3.1). Furthermore, frozen-thawed sperm from group E2.5 had the numerically highest total and progressive motility (CASA) and cell membrane functionality (HOS) and the lowest percentage of early apoptotic sperm (Annexin-V). However, acrosome membrane integrity (PSA) of E5 had the lowest mean (p < .05), whereas E2.5 caused a small nonsignificant decrease (69.1 ± 1.4%) compared to E0 and F0. In conclusion, 2.5 mM encapsulated GSH in semen extender significantly improved the quality of frozen-thawed bull sperm.

Effects of different ultrastructures of lecithin on cryosurvival of goat spermatozoa.

This study was to evaluate the effects of two different ultrastructures of lecithin including nanoparticles (NPE mostly nanomicelles) and lecithin nanoliposome (NLE) with egg yolk extender (EYE) on goat sperm cryopreservation. Semen samples were collected from 6 goats, then pooled, diluted and then frozen. Motility and motion parameters, plasma membrane integrity and functionality, morphology, apoptosis status (Annexin V-PI), acrosome integrity, DNA fragmentation and in vitro fertilisation were assessed. Total motility and most motion parameters were higher in EYE (p < .05) compared with the two lecithin extenders, while there were no significant differences between NLE and NPE. NLE and NPE had higher values for viable spermatozoa (Annexin V-PI) (p < .05) compared with EYE. The highest value for dead spermatozoa was observed in EYE (p = .08). A higher percentage of DNA fragmentation (p < .05) was detected in EYE compared with NPE. Plasma membrane integrity and functionality, morphology, acrosome integrity and fertility of spermatozoa indicated no significant differences between extenders. Data suggested that ultrastructural changes of lecithin (micelles versus. liposome) could not improve the sperm cryosurvival of goat spermatozoa. Moreover, we cannot also claim that lecithin-based diluent supplies better protection compared with the egg yolk in goat.

Conjugated linoleic acid improves meiotic spindle morphology and developmental competence of heat-stressed bovine oocyte.

This study was conducted to elucidate the effects of introducing conjugated linoleic acid (CLA) on meiotic spindle organization of heat stressed (HS) matured oocytes and the resulting blastocysts DNA methylation as well as the expression of the genes involved in DNA methylation (DNMT3a, DNMT3b and DNMT1). Immature bovine oocytes were cultured at 41 °C for the first 12 h and 38.5 °C for the second 12 h of maturation time in the presence of 0 and 50 µM of CLA (HS and HS + CLA groups, respectively). A group of oocytes cultured in medium with no CLA supplementation at normal temperature (38.5 °C for 24 h) was considered as negative control (C). Percentage of normal spindle, and cleavage and blastocyst rates were significantly decreased in the HS group compared to the C group (P < 0.05). The global DNA methylation and expression level of DNMT3a gene were increased in HS group compared to the C groups (P < 0.05), while the expression level of DNMT3b was decreased. The CLA supplementation improved the percentage of normal microtubules shape in MII oocytes as well as the developmental competence in the HS + CLA group compared to the HS group (P < 0.05). However, global DNA methylation and expression level of DNMT3a/b were not ameliorated by CLA supplementation (P > 0.05). Based on the obtained results, CLA proved to be capable of improving the oocyte developmental competence as well as decreased the aberrant spindle organization of heat-stressed oocytes and it would not cause epigenetic alteration in the obtained blastocysts.

Dietary omega-3 fatty acids from linseed oil improve quality of post-thaw but not fresh sperm in Holstein bulls.

Docosahexaenoic acid (DHA), a member of the n-3 fatty acid family present in fish oil, has several positive effects on bovine sperm, including membrane integrity, motility and viability, as well as cold sensitivity. Our objective was to investigate effects of varying amounts of omega-3 fatty acids from linseed oil, administered orally, on quality of fresh and frozen-thawed bull sperm. Twenty fertile Holstein bulls (874 ± 45.38 kg) were randomly and equally assigned to four groups and received encapsulated (rumen-protected) fats for 12 weeks, as follows: group P, 300 g palm oil; group Pl, 200 g palm oil + 100 g linseed oil; group pL, 100 g palm oil + 200 g linseed oil; and group L, 300 g linseed oil. Sperm quality of fresh and frozen-thawed semen was evaluated by routine assays including sperm motion characteristics (CASA), membrane integrity (eosin-nigrosin), membrane activity (hypo-osmotic swelling test; HOST) and malondialdehyde (MDA) content. There were no significant differences among groups in semen volume, sperm concentration or sperm quality parameters in fresh semen. However, after freezing-thawing, total and progressive motility in group P (59.61 ± 1.95 and 40.19 ± 2.48%, respectively; LSM ± SEM) were lower (P < 0.05) than in groups Pl (66.06 ± 1.95 and 47.53 ± 2.48%), pL (65.67 ± 1.95 and 47.48 ± 2.48%) and L (65.36 ± 1.95 and 47.62 ± 2.48)%, with no significant differences among the latter three groups. Furthermore, membrane integrity (eosin-nigrosin) and activity (HOST) were lower (P < 0.05) in group P (55.79 ± 2.15 and 42.19 ± 2.17%) compared to groups Pl (62.73 ± 2.15 and 48.93 ± 2.17%), pL (64.06 ± 2.15 and 50.01 ± 2.17%) and L (64.47 ± 2.15 and 49.68 ± 2.17%), with no significant differences among the latter three. Furthermore, there were more (P < 0.05) morphologically abnormal sperm in group P (25.99 ± 1.62%) than in groups Pl, PL and L (21.55 ± 1.62, 21.69 ± 1.62 and 20.90 ± 1.62%). In conclusion, feeding Holstein bulls 100-300 g linseed oil daily improved sperm cryotolerance.

In vitro supplementation of trans-10, cis-12 conjugated linoleic acid ameliorated deleterious effect of heat stress on bovine oocyte developmental competence.

Environmental stresses, such as heat stress (HS), have been shown to have diverse effects on the developmental competence of oocytes. The aim of this study was to determine the effect of exogenous conjugated linoleic acid (CLA) supplementation in maturation medium on bovine oocyte maturation and developmental competence under HS condition. Accordingly, cumulus-oocyte complexes (COCs) were cultured at 41 °C and 38.5 °C for the first and second 12 h of maturation in the presence of 0 (PC), 50 (CLA50-HS) and 100 (CLA100-HS) µM CLA. Also, a group of COCs were cultured at 38.5 °C for 24 h of maturation without CLA supplementation as negative control (NC). Nuclear maturation, level of intracellular glutathione (GSH), reactive oxygen species (ROS) content, cleavage and blastocyst rates as well as relative expression of BAX, and BCL2 genes in blastocysts were investigated. Our finding for the PC and NC groups revealed that HS decreased the percentage of MII oocytes, cleavage and blastocyst rates (P < 0.05). Moreover, HS lead to an increase in ROS levels and relative expression of BAX gene, decreased the intracellular content of GSH and relative expression of BCL2 gene (P < 0.05). However, the cleavage and blastocyst rates tended to increase in the CLA-supplemented groups compared to PC group (p < 0.10). Also, ROS and GSH levels in the matured oocytes decreased and increased in the CLA50-HS group compared to the PC group (P < 0.05), respectively. The ratio of expression levels of BAX to BCL2 genes was not different between the PC and CLA50-HS groups (P > 0.05). These findings suggest that HS has undesirable effects on the maturation competence of bovine oocyte and subsequent embryo development while administration of CLA can ameliorate some of adverse effects of HS.

Comparison of two different antioxidants in a nano lecithin-based extender for bull sperm cryopreservation.

The objective of the present study was to assess the effect of two different antioxidants, enzymatic compared with non-enzymatic, in a nano lecithin-based extender on post-thaw bull sperm quality. Semen samples (n = 36) were collected from six bulls. In the first experiment, 11 different extenders were prepared by adding five quantities of vitamin E (α-tocopherol) as a non-enzymatic antioxidant (VE: 0.1, 0.2, 0.4, 0.6 and 1.0 mM), or four quantities of glutathione peroxidase (GPx) as an enzymatic antioxidant (GPx: 0.5, 1, 2 and 3 mM) to the extender. Other extenders were a Control 1 (C1: Extender with ethanol) and Control 2 (C2: Extender without ethanol). Sperm motility (CASA), plasma membrane functionality test (HOST) and lipid peroxidation (MDA) were assessed to determine the optimal treatment in the first experiment. In the second experiment, the optimally supplemented group from the first experiment (GPx-1) was compared to C2 group. Apoptotic-like changes (Annexin staining), mitochondrial activity (Rhodamine-123 staining), acrosome integrity (PSA staining), DNA fragmentation (SCSA test) and in vitro embryo production capacity were evaluated. In the first experiment, there were the greatest percentages of plasma membrane functionality and least MDA (P ≤ 0.05) in sperm diluted GPx-1 group. In the second experiment, percentage of live sperm, blastocyst formation and hatching rate were greater (P ≤ 0.05) in the GPx-1 group compared with C2 group. In conclusion, data indicate adding 1.0 mM GPx as an enzymatic antioxidant to the nano lecithin-based extender can improve post-thaw quality and in vitro fertility of bull sperm.

Letrozole, an aromatase inhibitor, reduces post-peak age-related regression of rooster reproductive performance.

This study was designed to evaluate orally administrated Letrozole (Lz) on reproductive performance, plasma testosterone and estradiol concentrations and relative abundance of mRNA of GnRH, FSH and LH in roosters. Ross 308 roosters (n=32) that were 40-weeks of age were individually housed and received a basal standard diet supplemented different amounts of capsulated Lz [0 (Lz-0), 0.5 (Lz-0.5), 1 (Lz-1) or 1.5 (Lz-1.5), mg Lz/bird/day] for 12 weeks. Sperm quality variables and plasma testosterone and estradiol concentrations were assessed from the first to the tenth week of the treatment period. Semen samples from the 11th to 12th week were used for artificial insemination and eggs were collected and allotted to assess fertility and hatchability rates. Relative abundance of hypothalamic and pituitary GnRH, LH and FSH mRNA was evaluated at the end of 12th week. The results indicated that total and forward sperm motility as well as egg hatchability rate were greater in the Lz-0.5 group. Greater sperm concentrations, ejaculate volume, sperm plasma membrane integrity, testis index and fertility rates were recorded for both Lz-0.5 and Lz-1 groups compared with the Lz-0 group (P<0.05). Body weight, percentage of sperm abnormalities, and sperm plasma membrane functionality were not affected by treatment. Testosterone and estradiol concentrations were negatively related with greater testosterone concentrations in the Lz-1.5 group which had lesser estradiol concentrations. Relative mRNA transcript abundance for GnRH, LH and FSH was Lz dose responsive being greater in the treated groups; however, this trend plateaued for GnRH and for the relative abundance of both LH and FSH mRNA was less in the Lz-1.5 group than the other treatment groups. It is concluded that Lz may be an effective treatment to improve age related post-peak reproductive performance of roosters.

Fertility response of artificial insemination methods in sheep with fresh and frozen-thawed semen.

The aim of this study was to evaluate the fertility response of artificial insemination (AI) methods with fresh and frozen sperm in sheep. In experiment 1, one hundred and fifty fat tailed Zandi ewes were assigned into 3 equal groups and inseminated with three AI methods consisting of vaginal, laparoscopic and trans-cervical AI with fresh semen. In experiment 2, a factorial study (3 AI methods × 2 extenders) was used to analyze the effects of three AI methods and two freezing extenders containing soybean lecithin (SL) or Egg yolk (EY) on reproductive performance of 300 fat tailed Zandi ewes. Also, total motility, progressive motility, viability and lipid peroxidation of semen were evaluated after freeze-thawing in two extenders. In result, there was no significant difference among three AI methods when fresh semen was used. In experiment 2, the highest percentage of pregnancy rate, parturition rate and lambing rate were obtained in laparoscopic AI group (P < 0.05). Although pregnancy rate, parturition rate and lambing rate in trans-cervical group were higher (P < 0.05) than vaginal group, the results were not as high as laparoscopic group. No difference was observed between SL and EY extenders and their performance was close to each other. It can be concluded that although no difference was observed on reproductive performance for fresh semen, trans-cervical AI was more efficient than vaginal method when frozen-thawed semen was used, but its efficiency was not as high as laparoscopic method. Also, SL extender can be an efficient alternative extender to preserve ram sperm during cryopreservation procedure without adverse effects of EY.

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.

In vitro assessment of soybean lecithin and egg yolk based diluents for cryopreservation of goat semen.

Soybean lecithin is a suitable plant-based cryoprotectant for freezing ruminant sperm. Optimum level of lecithin was not clear for goat semen cryopreservation. The objective of this study was to investigate the effects of different levels of soybean lecithin in semen extender on post-thaw sperm quality including CASA-motion parameters, viability, plasma membrane integrity and lipid peroxidation. Semen samples were collected from 4 Mahabadi bucks using an artificial vagina. Different concentrations of soy lecithin (SL, 0.5%, 1%, 1.5%, 2% and 2.5% w/v) were compared to 15% (v/v) egg yolk-based extender (TR-EY). No significant difference was observed for sperm progressive motility, viability or plasma membrane integrity in 1.5% SL media (33.8%, 66%, and 62.7%, respectively) and TR-EY medium (35.4%, 67.2%, and 64.9%, respectively). Sperm motion characteristics (VAP, VSL, VCL, ALH and LIN) and rapid spermatozoa were improved with extender containing 1% and 1.5% SL, compared to TR-EY extender. Furthermore, egg yolk produced significantly higher malondialdehyde (4.02±0.21) than other groups. Results suggest that the optimal lecithin concentration in the semen extender was 1.5% and also soy lecithin can substitute for egg yolk during cryopreservation for caprine sperm.

Trehalose and glycerol have a dose-dependent synergistic effect on the post-thawing quality of ram semen cryopreserved in a soybean lecithin-based extender.

The objective of this study was to examine the interaction of different concentrations of trehalose [0 (T0), 50 (T50) or 100 (T100) mM] and glycerol [5% (G5) or 7% (G7)] on post-thawed quality of ram semen, cryopreserved in a soybean lecithin (SL)-based extender. Twenty-eight ejaculates were collected from four rams and diluted with six trehalose/glycerol combinations: T0G5, T50G5, T100G5, T0G7, T50G7, and T100G7. Sperm motility (CASA), membrane integrity (eosin/nigrosin) and functionality (HOST), abnormal forms, capacitation status (CTC), mitochondrial activity (rhodamine 123), apoptotic features (Annexin V/propidium iodide) and lipoperoxidation (malondialdehyde production) were evaluated after thawing. Extender T100G5 yielded the highest results for total and progressive motility, sperm velocity, normal morphology, functional membranes, active mitochondria and membrane integrity, with P<0.05 in general, except for T50G7 (P>0.05). The combinations T0G5, T0G7 and T100G7 yielded the lowest post-thaw quality. We could not detect significant changes in other kinematic parameters, capacitation status or lipoperoxidation. We conclude that, in our SL-based extender, a combination of 100 mM trehalose and 5% glycerol was the most adequate combination to achieving post-thawing quality in our soybean lecithin-based extender, and our results support that a synergistic effect among trehalose and glycerol exists. We suggest that other combinations could improve these results.

Fatty Acid Prof iles of Ram's Sperm after Removing Some Fatty Acid Sources from the Diets and Persistency of Fatty Acids in Sperm.

BACKGROUND: Mammalian spermatozoa are characterized by a high proportion of polyunsaturated fatty acids (PUFAs), but reliable data concerning dietary effects on fatty acid (FA) profile in ram's sperm and the persistency of FA in the ration to the FA in sperm has not been reported. Therefore, the aim of this study was to determine the stability of saturated and unsaturated FAs in ram's sperm despite removing FA sources from their diet. MATERIALS AND METHODS: Nine Kalkoohi rams were used in a completely randomized design and they were assigned to 3 groups. The treatments were diet supplemented (35 g/d/ram) by C16:0 (RP-10®), C18: 2 (Sunflower oil; SO) and n-3 (Fish oil; FO) with Vitamin E. Fifteen weeks after the start of the supplemented diet, rams were offered a basal diet without any supplementary FA source for 35 days when the sperm's FA ratio was determined. The data were analyzed by ANOVA (Analysis of variance) using the General Linear Model (GLM) procedure of SAS Institute. RESULTS: THIRTY FIVE DAYS AFTER REMOVING THE FAT SUPPLEMENT FROM THE DIET, MAJOR FA IN SPERM CONSISTED OF: C14:0, C16:0, C18:0, C18:1 cis, C18:2 cis and C22:6 n-3 docosahexaenoic acid (DHA). The percentage of C14:0 (p=0.8) and C18:1 cis (P =0.4) were similar among all the treatments. Interestingly, 35 days after the removal of fatty acid source, the percentage of C22:6 was highest in the FO treated group. CONCLUSION: The different sperm FA profile among various groups suggests that dietary FA had significant direct or indirect impacts on sperm FA profile after 35 days which might lead to physical and chemical changes in sperm characteristics.

Improvement of Semen Quality in Holstein Bulls during Heat Stress by Dietary Supplementation of Omega-3 Fatty Acids.

BACKGROUND: Long-chain polyunsaturated fatty acids (PUFAs) of the omega-3 family are important for sperm membrane integrity, sperm motility and viability. There are evidences to suggest that dietary supplementation with omega-3 fatty acids affects reproduction in men and males of different animal species. Therefore, the aim of current study was to investigate changes in the quality parameters of Holstein bull semen during heat stress and the effect of feeding a source of omega-3 fatty acids during this period. MATERIALS AND METHODS: Samples were obtained from 19 Holstein bulls during the expected time of heat stress in Iran (June to September 2009). Control group (n=10) were fed a standard concentrate feed while the treatment group (n=9) had this feed top dressed with 100 g of an omega-3 enriched nutriceutical. Semen volume, sperm concentration and total sperm production were evaluated on ejaculates collected after 1, 5, 9 and 12 weeks of supplementation. Moreover, computer-assisted assessment of sperm motility, viability (eosin-nigrosin) and hypo-osmotic swelling test (HOST) were conducted. RESULTS: Heat stress affected sperm quality parameters by weeks five and nine of the study (p<0.05). Supplementation significantly increased total motility, progressive motility, HOST-positive spermatozoa and average path velocity in the fresh semen of bulls (p<0.05). CONCLUSION: Dietary omega-3 supplementation improved in vitro quality and motility parameters of fresh semen in Holstein bulls. However, this effect was not evident in frozen-thawed semen.

Nutritive value of some herbage for dromedary camels in the central arid zone of Iran.

The purpose of this study is to prepare standard tables of the chemical composition of feedstuff and to determine the digestibility and palatability of different plant species in the dromedary camel, this research was conducted considering the consumed herbages by camels in the central arid zone of Iran. The following plant species were included: Alhagi camelorum, Artemisia sieberi, Atriplex lentiformis, Haloxylon persicum, Hammada salicornica, Salsola tomentosa, Salsola rigida, Seidlitzia rosmarinus, Suaeda fruticosa, Tamarix tree, and Tamarix kotschi. Thirty samples of the browsing parts were collected from three sites in the rangelands of Qom and Yazd province. The chemical composition of the samples, including dry matter, crude protein (CP), crude fiber, neutral detergent fiber (NDF), acid detergent fiber (ADF), ether extract, total ash, macroelements (Ca, P, Mg, K), microelements, and gross energy were measured. The in vitro digestibility of the plants was measured by camel liquor using the Tilley and Terry method. The palatability of the plants was measured by four mature camels in cafeteria trials. Data were analyzed by general linear model method using the SAS software. The highest CP (17.5%) related to Haloxylon persicum and the lowest NDF (26.2%) and ADF (12.6%) were related to Salsola rigida. The lowest CP (5.5%) and the highest NDF (72.8%) and ADF (59.6%) were related to Artemisia sieberi. The results also indicate that Atriplex lentiformis, Alhagi camelorum, Seidlitzia rosmarinus, Suaeda fruticosa, Haloxylon persicum, Salsola tomentosa, Hammada salicornica, T. kotschi, Salsola rigida, Tamarix tree, and Artemisia seiberi were more pleasurable feeds, respectively. There was no consistent relationship between the palatability of herbages with the percentage of digestible organic matter in the dry matter or chemical composition.

Unexpected detrimental effect of Insulin like growth factor-1 on bovine oocyte developmental competence under heat stress.

PURPOSE: To investigate the effects of Insulin like growth factor-1 (IGF-1) on bovine oocyte developmental competence under heat stress. METHODS: In Experiment 1, bovine cumulus-oocyte complexes (COCs) were cultured at 38.5 or 41 degrees C for the first 12 h of maturation in the presence of either 100 ng/ml human recombinant (hr)-IGF-1 or acetic acid. In Experiment 2, COCs were cultured in 38.5 or 41 degrees C for the first 12 h of maturation in the presence either of 100 ng/ml hr-IGF-1 or acetic acid. After fertilization, putative zygotes were cultured for 8 days. RESULTS: In experiment 1, addition of rh-IGF-1 to maturation medium at 38.5 degrees C significantly increased the proportion of M II oocytes and decreased the percentage of TUNEL-positive oocytes compared to the other groups. However, addition of rh-IGF-1 to maturation medium under heat stress increased the percentage of TUNEL-positive oocytes. In experiment 2, addition of rh-IGF-1 under heat sress did not affect cleavage rate, whereas, blastocyst formation rate decreased in heat-stressed and heat-stressed plus rh-IGF-1 groups. Similarly, The number of trophectoderm cells and total cell number were decreased in heat-stressed and heat-stressed plus rh-IGF-1 groups and the percentage of TUNEL-positive nuclei were increased in heat-stressed and heat-stressed plus rh-IGF-1 groups compared to the other groups. CONCLUSION: The results of the present study demonstrate that IGF-1 decreases oocyte developmental competence and total cell number and increases TUNEL-positive nuclei at heat stress condition. These unexpected results of IGF-1 during maturation period under heat stress condition warrant further optimizations and investigations.