Age-dependent changes in metabolic profile of turkey spermatozoa as assessed by NMR analysis

A review of antioxidant strategies to improve reproduction in aging male broiler breeders

As only 10% of the broiler breeder flock is roosters, their fertility is very important. The rooster sperm plasma membrane has high concentrations of polyunsaturated fatty acids that are sensitive to oxidative stress. Lipid peroxidation can change membrane structure, permeability, and fluidity, adversely affecting the acrosome reaction and fertility. Aging roosters have decreases in sexual behavior, serum androgen concentrations, sperm quantity and quality, and fertility. Low fertility in aging roosters is attributed to an imbalanced testicular oxidant-antioxidant system, with increased reactive oxygen species (ROS) damaging spermatogenic epithelium. However, antioxidant components can enhance antioxidant defenses in aging broiler breeder roosters. Protection against oxidative damage, particularly in the testes, improves reproductive hormone concentrations, testicular histology, sperm membrane function, and mitochondrial activity and thereby improves semen volume, sperm concentration, viability, motility, and sperm polyunsaturated fatty acid content, sperm-egg penetration, fertility, and reproductive performance. This review summarizes antioxidants that could improve fertility and reproductive performance and delay or prevent age-related declines in broiler breeder roosters, with benefits for poultry production.

Dataset on sperm quality parameters and NMR-detected changes in metabolic profile of fresh and frozen turkey spermatozoa related to two different reproductive period ages

Significant changes in the quality and metabolic profile of fresh turkey sperm as a result of both cryopreservation and reproductive age have already been individually confirmed in our previous studies. This new dataset adds a relevant piece to the tangled puzzle of changes in metabolite levels affecting cryopreserved turkey sperm quality, taking into consideration two different reproductive period ages. Fresh semen samples were collected at 44 and 56 weeks of age and exposed to the cryopreservation process. All fresh and frozen-thawed samples were subjected to analysis of mobility, viability and osmotic tolerance as parameters for evaluating the sperm quality, while NMR spectroscopy was used to assess the quantitative changes in water and lipid-soluble metabolites. Our results showed that the cryopreservation process significantly affected all of the measured qualitative parameters both at 44 and 56 weeks. Concerning the metabolic profile, a greater number of quantitative changes for both water and lipid-soluble components were found in frozen semen at 56 weeks than at 44 weeks of age. These data could contribute to identifying new strategies aimed at improving freezing procedures even as reproductive age increases.

Effects of dietary supplementation of tomato pomace (Solanum lycopersicum L.) and L-Arg on reproductive performance of aged male broiler breeders

This study aimed to investigate the effects of different dietary supplementation of tomato pomace (TP) and L-arginine (L-Arg) supplementation on sperm characteristics, reproductive performance, and semen biochemical components of aged commercial male broiler breeders. Thirty Ross 308 male broiler breeders (58 wk old) were provided and assigned to 5 dietary treatment groups, including control (CON), 5% TP (TPS-5), 10% TP (TPS-10), 15% TP (TPS-15), and L-Arg supplemented (10% above the recommendation, LAS-10). The results indicated that the semen volume increased in the TPS-15 group compared to that of the LAS-10 (and CON on wk 9) throughout the study (P < 0.05). The sperm concentration significantly increased in TPS-10 and TPS-15 groups in comparison to the other experimental groups. On wk 5 and 7, the sperm viability increased in all TPS groups compared to the CON and LAS-10, while on wk 9, it only increased in the TPS-10 group in comparison to the LAS-10 group (P < 0.05). The hypo-osmotic swelling test decreased in the LAS-10 group compared to the other experimental groups on wk 5 and all TPS groups on wk 7 and 9 (P < 0.05). The sperm total motility and forward progressive motility decreased in the LAS-10 group compared to the other experimental groups (P < 0.05). In contrast, unprogressive motility and immotile sperms were increased in the LAS-10 group compared to the other experimental groups (P < 0.05). In addition, the sperm penetration and fertility rate increased in TPS-10 and TPS-15 groups in comparison to CON and LAS-10 groups (P < 0.05). However, hatchability was reduced in the LAS-10 group (P < 0.05). The semen adenosine triphosphate increased in TPS-10, TPS-15, and LAS-10 groups compared to the CON (P < 0.05). Finally, the semen TAC and superoxidase dismutase decreased in the LAS-10 group (P < 0.05), while the glutathione peroxidase increased in the TPS-15 group (P < 0.05). In conclusion, 15% dietary TPS is recommended to improve the reproductive performance of aged commercial male broiler breeders.

The Lipidomics of Spermatozoa and Red Blood Cells Membrane Profile of Martina Franca Donkey: Preliminary Evaluation

Fatty acid-based lipidomic analysis has been widely used to evaluate health status in human medicine as well as in the veterinary field. In equine species, there has been a developing interest in fertility and sperm quality. Fatty acids, being the principal components of the membranes, play an active role in the regulation of the metabolic activities, and their role on spermiogenesis seems to be of great importance for the resulting quality of the sperm and, thus, fertility. With the application of widely used lipidomic techniques, the aim of this study was to evaluate: (a) the fatty acid content of the spermatozoa's membranes of 26 healthy male Martina Franca donkeys and its possible correlation with sperm parameters, and (b) the evaluation of the composition of the red blood cells' membrane. PUFA omega-6 are the principal components (40.38%) of the total PUFA content (47.79%) in both types of cells; however, DPA is the predominant one on the spermatozoa's membrane (27.57%) but is not present in the erythrocyte's membrane. Spermatozoa's motility (%) is positively correlated with stearic acid and EPA, and progressive motility (%), with oleic acid. These findings offer information on the composition of both types of cells' membranes in healthy male MF donkeys and reflect the metabolic transformations of the spermatozoa's membrane during the maturation period, providing a better perception of the role of fatty acids in sperm parameters and fertility.

The Effect of Semen Cryopreservation Process on Metabolomic Profiles of Turkey Sperm as Assessed by NMR Analysis

Semen cryopreservation represents the main tool for preservation of biodiversity; however, in avian species, the freezing−thawing process results in a sharp reduction in sperm quality and consequently fertility. Thus, to gain a first insight into the molecular basis of the cryopreservation of turkey sperm, the NMR-assessed metabolite profiles of fresh and frozen−thawed samples were herein investigated and compared with sperm qualitative parameters. Cryopreservation decreased the sperm viability, mobility, and osmotic tolerance of frozen−thawed samples. This decrease in sperm quality was associated with the variation in the levels of some metabolites in both aqueous and lipid sperm extracts, as investigated by NMR analysis. Higher amounts of the amino acids Ala, Ile, Leu, Phe, Tyr, and Val were found in fresh than in frozen−thawed sperm; on the contrary, Gly content increased after cryopreservation. A positive correlation (p < 0.01) between the amino acid levels and all qualitative parameters was found, except in the case of Gly, the levels of which were negatively correlated (p < 0.01) with sperm quality. Other water-soluble compounds, namely formate, lactate, AMP, creatine, and carnitine, turned out to be present at higher concentrations in fresh sperm, whereas cryopreserved samples showed increased levels of citrate and acetyl-carnitine. Frozen−thawed sperm also showed decreases in cholesterol and polyunsaturated fatty acids, whereas saturated fatty acids were found to be higher in cryopreserved than in fresh sperm. Interestingly, lactate, carnitine (p < 0.01), AMP, creatine, cholesterol, and phosphatidylcholine (p < 0.05) levels were positively correlated with all sperm quality parameters, whereas citrate (p < 0.01), fumarate, acetyl-carnitine, and saturated fatty acids (p < 0.05) showed negative correlations. A detailed discussion aimed at explaining these correlations in the sperm cell context is provided, returning a clearer scenario of metabolic changes occurring in turkey sperm cryopreservation.

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.

Nutritional modulation of fertility in male poultry

The increased consumption of protein derived from poultry demands greater poultry production, but increased poultry production (meat and eggs) is dependent on the fertility of the parent flocks. Clearly, the fertility of poultry flocks is associated with the fertility of both males and females, but the low numbers of males used for natural or artificial insemination mean that their role is more important. Thus, enhancing the semen volume, sperm concentration, viability, forward motility, and polyunsaturated fatty acids in sperm, as well as protecting against oxidative damage, could help to optimize the sperm membrane functionality, mitochondrial activity, and sperm-egg penetration, and thus fertility. Therefore, this review summarizes the nutritional factors that could improve the fertility of poultry males as well as their associated mechanisms to allow poultry producers to overcome low-fertility problems, especially in aging poultry males, thereby obtaining beneficial impacts on the poultry production industry.

Validation of the Turkey Semen Cryopreservation by Evaluating the Effect of Two Diluents and the Inseminating Doses

Simple Summary

Achieving an effective freezing protocol, that is able to preserve the fertilizing ability of turkey semen, is a key aim for the establishment of the first national semen cryobank of autochthonous chicken and turkey breeds within our national project (Tutela della biodiversità nelle razze avicole italiane—TuBAvI). In this regard, we have performed different studies in order to define the best conditions for cryopreservation of turkey semen; namely, we identified an effective freezing protocol which is based on the use of dimethylsulfoxide as a permeant cryoprotectant (CPA) combined with Ficoll as a non-permeant CPA. Here, our purpose was to test this protocol in vivo, by evaluating the effect of two extenders and three inseminating doses. The good fertility and hatching rates achieved here are promising for future studies, in which our cryopreservation protocol will be tested on Italian autochthonous turkey breeds and also to the advantages offered by the extensive use of frozen semen in the turkey breeding industry.

Abstract

This study was designed to test the fertilizing ability of cryopreserved turkey semen, and here, two experiments were performed: an in vitro analysis to assess the effects of Tselutin and Lake diluents and an in vivo test to determine the fertility and hatching rates by also studying the feat of three insemination doses (250, 400 and 600 × 10⁶ sperm/hen). Pooled semen samples were diluted with Tselutin or Lake extender which contained 20% of dimethylsulfoxide and 1 mM of Ficoll at final sperm concentration of 3 × 10⁹ sperm/mL. Thereafter, semen was packaged into straws and frozen on liquid nitrogen. The post-thaw sperm quality was evaluated considering motility (computer-aided sperm analysis—CASA system) and membrane integrity (flow cytometry). Significantly higher values of progressive motility and some kinetic parameters in semen frozen with Lake were found. When we compared the extenders in vivo, no significant effects were detected, whilst sperm concentration significantly affected both fertility and hatching rates, with the best results obtained with the sperm concentration of 400 × 10⁶ sperm/hen. From the results obtained, it emerged that the extender type only affected sperm motility characteristics, not the fertilizing ability of frozen-thawed semen, while inseminating dose markedly affected fertility and hatching rates.

Finding an Effective Freezing Protocol for Turkey Semen: Benefits of Ficoll as Non-Permeant Cryoprotectant and 1:4 as Dilution Rate

Simple Summary

The most adopted biotechnology for the conservation of genetic resources in avian species is semen cryopreservation. Therefore, the identification of a reference cryopreservation procedure represents a key point for ensuring the long-term conservation of genetic diversity in birds, through the implementation of a semen cryobank. In this study, our goal was to discover an effective freezing protocol for Meleagris gallopavo in order to realize the first Italian semen cryobank of autochthonous chicken and turkey breeds within our project (TuBAvI). For this purpose, we investigated the effects of three non-permeant cryoprotectants (sucrose, trehalose, and Ficoll) and two dilution rates (1:2 and 1:4) on the in vitro cryosurvivability of turkey spermatozoa. After thawing, the best semen quality was found in semen frozen in the presence of Ficoll and diluted at a final rate of 1:4. This paper provides encouraging results, however further studies are programmed to standardize the semen cryopreservation protocol.

Abstract

The present study aimed to find an effective cryopreservation protocol for turkey semen through the combined use of dimethylsulfoxide (DMSO) and three non-permeant cryoprotectants (NP-CPAs), sucrose, trehalose, and Ficoll 70. In addition, the action of two dilution rates (1:2 and 1:4) were also investigated. Semen was processed according to two final dilution rates and the following treatments: Tselutin extender (TE)/DMSO (control), TE/DMSO + sucrose or trehalose 50, 100, 200, or 400 mM, and TE/DMSO + Ficoll 0.5, 0.75, 1, or 1.5 mM. In total 26 different combinations treatments were achieved. The diluted semen was filled up into straws and frozen on liquid nitrogen vapor. The post-thawing sperm quality was assessed by analyzing motility, membrane integrity, osmotic resistance, and DNA integrity. The results obtained revealed a significant effect of NP-CPA concentration on total and progressive motility, on most of the kinetic parameters, on membrane integrity and DNA integrity, while the post-thaw quality was less affected by dilution rate. The highest post-thaw quality for all sperm quality parameters assessed except curvilinear velocity (VCL) and DNA integrity were found in semen frozen with 1 mM Ficoll/1:4 (p < 0.05). Our findings provide an important contribution for the identification of a reference procedure for turkey semen cryopreservation, in order to create the first national avian semen cryobank.

The effect of dietary coenzyme Q10 on plasma metabolites and hepatic gene expression in broiler breeder hens

1. This study was performed to evaluate the effects of dietary supplementation of coenzyme Q10 (CoQ10) on laying rate, body weight, plasma metabolites and some liver gene expression in broiler breeder hens. 2. A total of 128 broiler breeder hens (Arbor Acres Plus, 47 weeks of age) were randomly distributed to four dietary groups supplemented with different levels of CoQ10 (0, 300, 600 or 900 mg/kg diet) with four replicates of eight hens each. During 47-54 weeks of age, laying rate, egg mass and body weight were recorded weekly. To assay plasma biochemical indicators, blood samples were collected at 54 weeks of age. At the end of the experiment, for evaluating the abdominal fat weight, liver weight and expression of the adiponectin and proliferator-activated receptor-α (PPAR-α) genes in the liver, eight hens per treatment were selected, weighed and humanely killed by decapitation. 3. Dietary supplementation of CoQ10 linearly decreased abdominal fat weight, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities by increased levels of CoQ10. The plasma levels of glucose, cholesterol and alkaline phosphatase (ALP) activity were quadratically decreased by increased levels of CoQ10. The best plasma levels of glucose, cholesterol and ALP activity were estimated at 562.5, 633.3 and 517.8 mg CoQ10/kg diet, respectively. Adiponectin and PPARα gene expression exhibited a linear increased by increased levels of CoQ10. 4. In conclusion, addition of CoQ10 to the diet influenced lipid metabolism and expression of the adiponectin and PPAR-α genes, which might be partially due to the improvement in mitochondrial metabolism and energy production. However, further studies are necessary to determine the effects of CoQ10 on these indicators in broiler breeder hens during ageing.

Beneficial effects of dietary coenzyme Q10 on the productive and reproductive variables of broiler breeder hens

The aim of this study was to evaluate the effects of supplementary CoQ10 in the diets of aged broiler breeder hens on productive and reproductive variables. A total of 128 hens)44 weeks of age) were randomly assigned to one of 16 groups (eight hens per group). The hen-groups (with equal mean egg production and egg weight) were randomly assigned to one of four diet-groups to provide four pen/groups per treatment. There was no CoQ10 supplementation or supplemental amounts of either 300, 600 or 900 mg CoQ10/kg added to the basal diet. Egg production, weight, and mass were determined weekly. To assess fertility, hatchability, and sperm penetration (SP) rate, the hens were artificially inseminated on a weekly basis (from 47-54 weeks of age). The hens were weighed and killed at the end of the experiment for evaluation of the ovarian morphology, oviduct histology, utero-vaginal junction (UVJ) total antioxidant capacity (TAC), and Pdss2, GDF9, and BMP15 mRNA transcript abundances in the germinal disc regions. The results indicated that there was a linear response curve to increasing amounts of supplemental dietary CoQ10 on fertility, hatchability of eggs, SP rates, TAC of the UVJ, fold height and surface epithelia of the magnum and isthmus, and abundance of GDF9, BMP15 and Pdss2 mRNA transcripts in the germinal disc region. In conclusion, the findings of the present study indicate diet supplementation with CoQ10 had beneficial effects on the productive and reproductive variables of aged hens.

Use of supplemental dietary coenzyme Q10 to improve testicular function and fertilization capacity in aged broiler breeder roosters

In numerous studies it has been suggested that targeting mitochondria with specific compounds could efficiently inhibit various conditions associated with oxidative stress. The treatment of aged roosters with compounds such as coenzyme Q10 (CoQ10), may improve their reproductive performance by providing protection from oxidative stress. Therefore, this study was performed to assess the effect of supplemental dietary CoQ10 on the testicular function and fertility of aged broiler breeder roosters. A total of 36 roosters)47 weeks of age) were randomly divided into dietary treatments containing either 0, 300 or 600 mg CoQ10/kg diet. Three birds were allocated to each of four replicate groups in each dietary treatment. Between 47 and 54 weeks of age, ejaculates were obtained weekly from the three roosters in each replicate group. Samples in a replicate were pooled and analyzed as a single sample. Between 51 and 54 weeks of age, seminal plasma total antioxidant capacity (TAC), alanine amino transferase (ALAT) and aspartate amino transferase (ASAT) levels were assessed. Fertility, hatchability, and sperm penetration (SP) rates were likewise evaluated. Seminal volume, sperm concentration, sperm plasma membrane functionality, sperm plasma membrane integrity, seminiferous tubule diameter and seminiferous epithelium thickness exhibited quadratic increases in response to increasing levels of dietary CoQ10. Respectively, the 429.19, 433.33, 464.50, 613.50, 392.78 and 447.99 mg/kg dietary concentrations of CoQ10 provided the best results for each of the aforementioned variables. Also, other seminal traits, as well as testosterone concentration, fertility, and SP rates, displayed linear increases in response to the increasing levels of CoQ10. Dietary supplementation of CoQ10 linearly decreased seminal plasma ALAT and ASAT and linearly increased seminal plasma TAC. In conclusion, CoQ10 supplementation in the diet (a minimum of 300 mg CoQ10/kg diet) has the potential to improve the reproductive performance of aged broiler breeder roosters.

Uncovering sperm metabolome to discover biomarkers for bull fertility

Background

Subfertility decreases the efficiency of the cattle industry because artificial insemination employs spermatozoa from a single bull to inseminate thousands of cows. Variation in bull fertility has been demonstrated even among those animals exhibiting normal sperm numbers, motility, and morphology. Despite advances in research, molecular and cellular mechanisms underlying the causes of low fertility in some bulls have not been fully elucidated. In this study, we investigated the metabolic profile of bull spermatozoa using non-targeted metabolomics. Statistical analysis and bioinformatic tools were employed to evaluate the metabolic profiles high and low fertility groups. Metabolic pathways associated with the sperm metabolome were also reported.

Results

A total of 22 distinct metabolites were detected in spermatozoa from bulls with high fertility (HF) or low fertility (LF) phenotype. The major metabolite classes of bovine sperm were organic acids/derivatives and fatty acids/conjugates. We demonstrated that the abundance ratios of five sperm metabolites were statistically different between HF and LF groups including gamma-aminobutyric acid (GABA), carbamate, benzoic acid, lactic acid, and palmitic acid. Metabolites with different abundances in HF and LF bulls had also VIP scores of greater than 1.5 and AUC- ROC curves of more than 80%. In addition, four metabolic pathways associated with differential metabolites namely alanine, aspartate and glutamate metabolism, β-alanine metabolism, glycolysis or gluconeogenesis, and pyruvate metabolism were also explored.

Conclusions

This is the first study aimed at ascertaining the metabolome of spermatozoa from bulls with different fertility phenotype using gas chromatography-mass spectrometry. We identified five metabolites in the two groups of sires and such molecules can be used, in the future, as key indicators of bull fertility.