Abstract
Subfertility is a multifactorial disorder that affects the rabbit production industry. However, subfertility may be treated by using a simple intervention such as vitamin supplementation. Vitamin E and selenium (Se) are potent antioxidants that protect the male reproductive system. The aim of this study is to determine the effects of vitamin E and Se on testicular size, semen quality and freezability, antioxidant activity, testosterone levels, and fertility in subfertile rabbits. Twenty-one New Zealand rabbits were classified as subfertile rabbits based on their semen characteristics and fertility records. The rabbits were randomly allocated into 3 equal groups (G1: control; G2: injected with Vit E 100 IU/head + Se 0.1 mg/kg b.w.; G3: injected with Vit E 200 IU/head + Se 0.2 mg/kg b.w. once weekly for 8 weeks).Once weekly for 8 W, blood samples were collected to measure serum testosterone level and total antioxidant capacity (TAC), and semen samples were collected by artificial vagina to assess the quality of fresh and frozen semen. At the 8th week of the study, 150 multiparous does were artificially inseminated with fresh semen to assess the fertility of rabbits after treatment; 50 does for each group. At the end of the study, rabbits were slaughtered to assess testicular morphometry. Fresh and post-thaw semen quality parameters were significantly (p < 0.05) higher in G3in comparison with G2and G1, respectively. Also, testosterone level was significantly (p < 0.05) increased at the 2nd week in G3in comparison with other groups. Conception and kindling rates were significantly (p < 0.05) higher in does which were inseminated with semen fromG3. In conclusion, injection of vitamin E and selenium at a higher dose (G3) improved the testicular morphology, quality of fresh and post-thaw semen, and most importantly, the fertility of subfertile rabbits.
Similar content being viewed by others
Avoid common mistakes on your manuscript.
Introduction
Rabbits have a high reproductive rate compared to other livestock. In addition to being an excellent source of dietary protein for human nutrition, rabbits are an excellent model for the different aspects of research in reproduction (Fischer et al. 2012).
Fertility is the ability to produce offspring, while infertility is the inability to reproduce. Furthermore, subfertility is a complex condition (environmental, lifestyle, and genetic) that refers to the failure of conception for a long period of time. In the literature and clinical contexts, this phrase is frequently used wrongly as synonymous with infertility. However, subfertility may be treated by using a simple intervention such as vitamin supplementation (Salma et al. 2011).
Oxidative stress (OS) is an arising factor in unexplained male fertility problems (Sharlip et al. 2002). Furthermore, OS is characterized by excessive generation and accumulation of reactive oxygen species (ROS), which is accompanied by the decrement and weakness of the endogenous antioxidant system leading to oxidative damage of sperm proteins, lipids, and nucleic acids (Mannucci et al. 2022).
Rabbit sperm plasma membrane is highly vulnerable to free radicals induced lipid peroxidation due to containing high levels of polyunsaturated fatty acids (PUFAs) and low antioxidant levels within the cytoplasm (El-Gendy 2022).
Accordingly, many strategies can be used to mitigate the adverse effects of oxidative stress on reproduction using vitamins, minerals, and/or elements with antioxidant potential (Akarsu et al. 2023a, 2023b) thereby enhancing fertility potential (Brecchia et al. 2023).
Vitamin E (vit E) is a major fat-soluble antioxidant vitamin present in cell membranes that mitigates oxidative damage by breaking the chain reaction of peroxidation and inhibiting the generation of ROS. Furthermore, many previous studies revealed that the deficiency of vit E could adversely affect fertility potential (Wang et al. 2022). Moreover, it has the potential to neutralize free radicals, thereby protecting cell membranes from them (Kessopoulou et al. 1995).
Selenium (Se) is an important trace element responsible for various reproductive functions, including testicular development, spermatogenesis, and testosterone metabolism (Moslemi and Tavanbakhsh 2011). In addition, Se is a critical constituent of sperm capsule selenoproteins that protect the membrane from peroxidation by ROS and increase the activity of GSH-peroxidase (Burk and Hill 2009). Moreover, it is mostly found in the active sites of enzymes in the form of selenocysteine. Multiple Se-containing proteins, including GSH-Px and thioredoxin reductase, play critical roles in avoiding oxidative damage (Ventura et al. 2017). As a result, the usefulness of selenium supplementation in increasing internal antioxidant defense has been highlighted in recent years. Several previous studies were conducted on rabbits (Hosny et al. 2020)to study the effect of Vit E and se on the reproductive performance. On the other hand, no previous reports were conducted to investigate vit E and Se injection on the semen quality and fertility of subfertile rabbits. The aim of this study was to investigate the effect of repeated injection of vit E and Se on the quality of semen (fresh and frozen), testicular morphometry, testosterone, and total antioxidants capacity (TAC) levels, and the overall reproductive performance of the subfertile rabbits. We hypothesized that injection of vit E and Se once weekly for 8 W may improve the quality, preservability, and fertility potential of the semen, thereby enhancing testosterone levels and the antioxidant status of subfertile rabbits.
Materials and methods
Unless otherwise stated, all chemicals were purchased from Sigma-Aldrich (Madrid, Spain). The current investigation was conducted fromSeptember 2022 to April 2023 at Theriogenology Department Farm, Faculty of Veterinary Medicine, Cairo University, Egypt. All experimental procedures were reviewed and approved by the Ethical Committee for Animal use belonging to the Faculty of Veterinary Medicine, Cairo University, Egypt (Vet CU 03162023751).
Animals
Two hundred and forty-three rabbits were screened out using semen evaluation and fertility records to keep twenty-one adult New Zealand rabbits aged18 months, weighing 5–6 kg, for use in the present study. Rabbits had a history of decreasing fertility (low conception rate ˂ 30% after natural mating with fertile multiparous does for several times) and low semen quality (motility, viability percentages were < 60% and sperm cell concentrations were < 250 ˟ 106/ml; Fadl et al. 2019). Based on fertility records and rabbits’ semen characteristics, rabbits were identified as subfertile. Rabbits were individually housed in wire cages and fed a standard commercial diet (crude fibre 19%, crude protein 18%, fat 3%, phosphorus 0.5%, and calcium 1.00%) following the NRC guidelines (NRC 1977) and managed in a natural environment (temperatures ranged from 19 °C to 25 °C). Freshwater was freely accessible ad libitum. Rabbits were allotted into three groups: a control group (G1, n = 7) that received no antioxidant treatment (only saline) and two treatment groups (G2 & G3). G2 (n = 7) was injected intramuscularly with Vit E (100 IU/head) and Se (0.1 mg/kg b.w.), while G3 (n = 7) was injected with Vit E (200 IU/head) and Se (0.2 mg/kg b.w.). The treatment protocol for the studied rabbits was once weekly for eight successive weeks based on the duration of spermatogenesis in rabbits (about 53 d) (Swierstra and Foote 1965). The dose of Vit E and Se (Cairo Company for Medicine, Egypt) was selected based on a previous report (Meshreky and Metry 2000).
Experimental design
Experiment 1: Effects of repeated injections of Vit E and Se on the quality of fresh and frozen/thawed subfertile rabbit semen
Once per week for 8 consecutive weeks (from W1 to W8), semen was collected from rabbits using prewarmed (42ºC) and lubricated artificial vagina specified for rabbits. Immediately after semen collection, the gel portion was separated, and ejaculates were incubated at 37 ºC for sperm quality parameters (volume, concentration, motility, viability, and acrosome integrity) assessment. Collected ejaculates for each group were pooled to avoid individual variation between rabbits, and then pooled semen was evaluated.
For cryopreservation, pooled semen for each group was diluted (1:1) with INRA-82 extender (Vidament et al. 2000) and fortified with dimethyl formamide 4%+ dimethyl sulfoxide 4% as cryoprotectants (Fadl et al. 2019). Then, diluted semen samples were kept in the refrigerator at 5 °C for cooling (for 90 min) and equilibration (for 15 min). After equilibration, cooled semen was loaded into 0.5 mL plastic straws and sealed with polyvinyl powder. Straws were placed horizontally at 4 cm over liquid nitrogen (LN₂) vapours for 10 min and plunged into LN₂ for storage. For evaluation of post-thaw semen parameters (motility, viability, and acrosome integrity), straws (after at least one week in storage) were thawed using a water bath at 50 °C for 7 s (Di Iorio 2014).
Fresh and post-thaw semen evaluation
Volume and concentration
The ejaculate volume was assessed using a graduated tube. Sperm cell concentration was evaluated by the direct sperm cell count method using the Neubauer haemocytometer (Number of sperm counted* Dilution factor* 50,000 sperm/ml), according to Smith and Mayer (1955).
Individual motility
Individual motility was evaluated in fresh and post-thaw semen samples. A drop of semen was placed on a preheated 37 °C glass slide, covered with a cover slide (37 °C), and then examined under an optical microscope (Olympus® BH-2, made in Japan) with an adjusted hot stage at 38–40 °C. Semen samples were subjectively assessed for sperm motility by the same person after examination of several microscopic fields and recorded in 5% increments (range 0-100%) according to the method previously described by Evans and Maxwell (1987).
Viability and morphology
The viability and normal sperm morphology were evaluated using eosin-nigrosin stain, as mentioned previously by Evans and Maxwell (1987). In detail, a drop of fresh or post-thaw semen was mixed with a drop of the stain and smeared on a pre-warmed (37 °C) glass slide, left to dry, and then examined microscopically using a bright field microscope (1000×) to assess the viability and sperm morphology of a total of 200 spermatozoa. On the same slide used for viability assessment, the abnormal morphology of spermatozoa was recorded.
Acrosome integrity
Acrosome integrity was evaluated in fresh and frozen-thawed semen using Spermac stain (FertiPro N.V., Belgium) as previously described by Chan et al. (1999). Using a bright field microscope, a total of 200 sperm were recorded, and the percentages of intact acrosomes were calculated.
Experiment 2: Effects of repeated injections of Vit E and Se on the serum concentration testosterone and total antioxidant capacity of subfertile rabbit
Once per week for 8 consecutive weeks (from W1 to W8) in the morning before access feed, blood samples were obtained from the marginal ear vein of rabbits and placed into plain tubes. The drawn blood samples were subjected to centrifugation at 3000 rpm for 15 min and then the serum samples were collected and stored (− 20 ℃) for hormonal and biochemical analyses (Shetaewi 1998).
Serum testosterone concentration was measured as previously mentioned by Abraham et al. (1977) using commercial kits (Diagnostic Production Corporation, Los Angeles, USA).
Serum total antioxidant capacity (TAC) was determined spectrophotometrically using commercial kits (total antioxidant capacity, Bio-diagnostic, Dokki, Egypt), according to Ippoushi et al. (2005).
Experiment 3: Effects of repeated injections of Vit E and Se on the fertility of subfertile rabbit semen
One hundred and fifty New Zealand white multiparous does aged 10–12 months and weighing 4–6 kg have been used for evaluation the fertility of subfertile rabbit semen after repeated injections of Vit E and Se for 8 W. They were randomly allotted into three groups (n = 50 for each group). Fresh pooled semen for each group was diluted with INRA-82 extender. Dilution rates were calculated according to sperm cell concentration and insemination volume. Based on this, receptive does (vulvae lips have a dark pinkish coloration) were deeply inseminated with 0.5 mL of extended semen containing about 25 × 106 spermatozoa using a curved inseminating pipette (Imporvet, S.A.). Immediately after insemination, does were injected with buserelin acetate (Receptal; Intervet International GmbH Feldstrasse 1a D-85716Unterschleißheim, Germany) in a dose of 0.8 µg (0.2 ml/ doe) for induction of ovulation. On the 15th day after insemination, an ultrasound examination was performed to assess pregnancy and calculate the conception rate (number of pregnant females/number of inseminations). After parturition, kindling rates were calculated (number of does giving birth/number of inseminations).
Experiment 4: Effects of repeated injections of Vit E and Se on the testicular morphometery of subfertile rabbit
At the end of the study, three rabbits from each treatment were randomly selected and humanely sacrificed. After sacrifice, paired testes for each rabbit were dissected (without epididymis) for morphometric assessment (weight, length, width, and volume). To assess the testicular weight, an electronic scale was used for this purpose. Using a pair of vernier callipers, testicular length, and width were measured. Furthermore, testicular volumes in all bucks were determined by water displacement according to the Archimedes principle, as previously mentioned by Adu and Egbunike (2010).
Statistical analysis
The normality of data distributions was evaluated, and a two-way ANOVA was used to analyse fresh and frozen semen parameters, testosterone, and TAC levels. While conception and kindling rates and testicular morphometry results were analysed using a one-way ANOVA followed by a Bonferroni post-hoc test. Results are reported as mean ± standard error of the mean (SEM). For all analyses, P < 0.05 was considered significant. The IBM SPSS 27.0 Software Package was used to conduct statistical analyses (IBM Corp., New York, NY, USA).
Results
Semen parameters
The quality parameters of fresh semen were presented in Table 1. There were effects of treatment, week, and treatment*week interaction effects (P < 0.05). Individual motility, viability (W4 to W8), sperm cell concentration (W6 to W8), normal sperm morphology (W7 to W8) and intact acrosomes (W6 to W8) were significantly increased in G3 in comparison with G2 and G1 groups.
Post-thaw sperm parameters
There were effects of treatment, week and an interaction between treatment and week (P < 0.05). As depicted in Table 2, the percentage of post-thaw sperm motility (W3 to W8), viability (W3 to W8), normal sperm morphology (W4 to W8), and acrosome integrity (W4 to W8) was higher in G3 compared to other groups.
Serum testosterone and total antioxidant capacity (TAC) levels
Serum testosterone and TAC levels were presented in Fig. 1a, b. There were effects of treatment, week, and treatment*week interaction effects (P < 0.05). Serum testosterone concentrations and TAC levels were significantly increased in G3 from W2 to W8 compared to G1.
Fertility results
As depicted in Fig. 2, G3 showed a significant increase in conception and kindling rates in comparison with G2 and G1 groups.
Testicular morphometry
Testicular morphometry results are presented in Fig. 3. Values of testicular weight, length, width, and volume were significantly increased in G3 compared to other groups.
Discussion
The objective of the current study was to elucidate whether repeated injection of Vit E and Se affected the sperm quality and fertility of subfertile rabbits. No previous reports investigated the effects of the injection of Vit E and Se on the fresh and preserved semen quality, testosterone and TAC levels, and testicular size of subfertile rabbits. In the present study, treated groups (G3 and G2, respectively) had higher sperm (fresh and preserved) individual motility, viability and testosterone, TAC concentrations, conception, kindling rates, and testicular size compared to the control group (G1). These results supported the hypothesis that the injection of vitamin E and Se positively affects the quality and fertility parameters of fresh and cryopreserved semen from rabbits suffering from subfertility.
Semen quality is a good indicator of fertility (Bas et al. 2023). Rabbit sperm membrane contains high concentrations of polyunsaturated fatty acids, which makes the sperm cell very sensitive to peroxidative damage by ROS (Fadl et al. 2021). For normal sperm function, limited amounts of ROS are necessary. Despite the positive effect of ROS on sperm cell performance, excessive production, and accumulation of ROS could negatively affect motility, fertility, and freezing ability of sperm (Fadl et al. 2023). In the present study, the injection of Vit E and Se significantly improved the fresh and preserved semen quality of subfertile rabbits. These findings were in line with previous studies on rabbits (Yousef et al. 2003), men (Moslemi and Tavanbakhsh 2011), chickens (Khan et al. 2012), and rams (Luo et al. 2004). This improvement in semen quality was represented by enhancing sperm motility, viability, normal morphology, concentration, and normal acrosomes.
Furthermore, sperm motility and viability are good predictors of semen quality and future fertility, and they are most extensively enhanced by treatment. The present results were in line with several previous studies in rabbits (Yousef et al. 2003), men (Moslemi and Tavanbakhsh 2011), ganders (Bas et al. 2023) rams (Luo et al. 2004; Mahmoud et al. 2013), and mice (Saddein et al. 2019). This enhancement was attributed to the synergistic effect of Vit E and Se on the antioxidant system in the rabbit sperm against ROS. Furthermore, Vit E is a non-enzymatic antioxidant that protects sperm cell membranes and organelles (mitochondria) from being attacked by ROS, it acts in two possible ways. The direct way in which Vit E inhibits the chain reaction of lipid peroxidation (Balakrishnan et al. 2013). The indirect way in which Vit E stimulates and maintains the production of scavenger antioxidant enzymes that protect cell membranes from peroxidation and reduce apoptosis (Saddein et al. 2019). In addition, Vit E has a critical role in the protection of glutathione-dependent enzymes (Van Haaften et al. 2003). Interestingly, Se is an essential element for normal non defective motility through the formation of the phospholipid–hyperoxide GSH-Px enzyme, which is a structural protein of the mitochondrial capsule in the mid-piece of mature spermatozoa (Ursini et al. 1999).
In the present investigation, G3 rabbits had higher normal sperm morphology, acrosomes, and concentration in comparison with the other two groups. These results agreed with previous studies in rabbits (Gouda et al. 2021), rams (Mahmoud et al. 2013), mice (Arjmand et al. 2023), and drakes (Mostafa et al.2019). This improvement was attributed to the antioxidant action of Vit E and Se against oxidative damage to testicular tissues (Bas et al. 2023). Furthermore, Vit E and Se supplements result in increasing the diameter of the seminiferous tubule and thickness of the germinal cell layer, decreasing the relative area of interstitial tissue, and consequently, increasing sperm quality and concentration (Malaniuk and Lukaszewicz 2006; Edens and Sefton 2009; Bas et al. 2023).
Testosterone secretion is highly correlated with testicular activity. In the present study, injection of Vit E and Se in subfertile rabbit bucks increased testosterone concentrations from wk2 to wk8 of treatment. These findings were in accordance with previous studies in rabbits (Gouda et al. 2021), rams (Mahmoud et al. 2013), and goat bucks (Hong et al. 2009). This increase of testosterone concentrations was attributed to the positive effect of vitamin E on the testicular tissue. Furthermore, this positive effect is represented by increasing the width of seminiferous tubules and the relative volume densities of Leydig cells, and consequently, increasing testosterone production (Hong et al. 2009).
In addition, the total antioxidant system is responsible for scavenging excessive ROS and maintaining the balance between endogenous antioxidant and ROS production (Lewis et al. 1995). Furthermore, total antioxidant competence (TAC) is a good indicator of the endogenous antioxidant system potential. In the current investigation, TAC concentrations were significantly higher in G3 from wk2 to wk8 compared to G2 and G1, respectively. These findings revealed that the injection of Vit E and Se could increase the endogenous antioxidant potential of the testes against damage by peroxidation. These results were in line with a previous study in goat bucks (Hong et al. 2010).
In the present study, G3 had higher conception and kindling rates compared to other groups (G2 and G1, respectively) when they were inseminated with either fresh or frozen-thawed treated rabbit bucks sperm suffered from infertility. These findings agreed with previous studies in men (Sabetian et al. 2021; Ener et al. 2016). This improvement in vivo reproductive performance, which was represented by increasing conception and kindling rates, may be attributed to the antioxidant action of Vit E and Se against excessive ROS and, consequently, improvement of quality parameters of rabbit spermatozoa. Moreover, vit E and Se injection in male rabbits improved the fertility rate in the New Zealand rabbit does (Zeidan et al. 2006) Which is consistent with our results in rabbit does that were inseminated with subfertile rabbit bucks injected with vit E and Se. In the meantime, several studies reported that the addition of vit E and Se to the semen extender improved the freezability of rabbit bucks’ semen in normal and under heat stress conditions (Thuwanut et al. 2013; Zhu et al. 2015). But there are no previous reports regarding the effect of vit E and Se injection effect on the freezability of rabbit bucks, especially in subfertile ones.
Interestingly, testicular morphometric measurements (weight, length, width, and volume) are good indicators for the spermatogenesis process and sperm production. In the present investigation, administration of Vit E and Se in G3 significantly increased the testicular morphometric measures compared to G2 and G1, respectively. These findings were in line with previous studies in rabbits (El-Azzazi et al. 2016; Kamel 2012), rams (Mahmoud et al. 2013) and rats (Oda et al. 2012). This increment was attributed to the positive effect of Vit E and Se on the Leydig and Sertoli cells and, consequently, increasing testosterone and androgen binding protein production. In addition, testosterone has a critical role in preserving the spermatogenesis process through increasing cell division and decreasing apoptosis (Mostafa et al. 2019). Furthermore, Vit E leads to increasing interstitial cell density and seminiferous tubules diameter (El-Azzazi et al. 2016).
Conclusions
In conclusion, injecting Vit E (200 IU/head) and Se (0.2 mg/kg b.w) once weekly for 8weeks enhanced sperm quality, quantity, fertility and antioxidant status potential in rabbit buck sperm, as well as conferring superior protection against subfertility. However, more research is needed to study its effects on the molecular level in relation to oxidative and apoptotic genes on both levels, testes and spermatozoa.
Data availability
No datasets were generated or analysed during the current study.
References
Abraham GE, Manilos FS, Garza R (1977) Radioimmunoassay of steroids. In: Abraham GE (ed) Handbook of radioimmunoassay. Marcel Dekker, New York, pp 591–656
Adu OA, Egbunike GN (2010) Fertility, semen quality and reproductive organ weights of boars fed dietary copper. J Appl Agricul Res 2:61–76
Akarsu SA, Acısu TC, Güngör İH, Çakır Cihangiroğlu A, Koca RH, Türk G, ... Esmer Duruel HE (2023a) The effect of luteolin on spermatological parameters, apoptosis, oxidative stress rate in freezing rabbit semen. Pol J Vet Sci 91–98
Akarsu SA, Güngör İH, Cihangiroğlu AÇ, Acısu TC, Koca RH, Türk G,... Gür S (2023b) Effect of sulforaphane on long-term storage of rabbit semen. Anim Reprod 20:e20230001
Arjmand K, Daneshi E, Pourmasumi S, Fathi F, Nasseri S, Sabeti P (2023) Evaluation of the effect of vitamin E on reproductive parameters in morphine-treated male mice. Addict Health 15:177–184. https://doi.org/10.34172/ahj.2023.1415
Balakrishnan R, Satish Kumar CS, Rani MU, Srikanth MK, Boobalan G, Reddy AG (2013) An evaluation of the protective role of α-tocopherol on free radical induced hepatotoxicity and nephrotoxicity due to chromium in rats. Indian J Pharmacol 45:490–495. https://doi.org/10.4103/0253-7613.117778
Baş H, Taşkesen HO, Boz MA, Sarıca M, Erensoy K, Dotas V, Symeon G (2023) The effects of varying combinations of dietary selenium, vitamin E, and zinc supplements on antioxidant enzyme activity, and developmental and histological traits in testicular tissues of 1-year-old native Turkish ganders. Sustainability 15:12245. https://doi.org/10.3390/su151612245
Brecchia G, Muça G, Munga A, Menchetti L, Galosi L, Rossi G, Barbato O, Pastorelli G, Agradi S, Serra V, Sulçe M, Ozuni E, Turmalaj L, Castrica M, Ceccarini MR, Riva F, Fioretti B, Quattrone A, Marongiu ML, Curone G (2023) Goji Berry in the diet of the rabbit buck: effects on semen quality, oxidative status and histological features of the reproductive tract. Antioxidants 12:1959. https://doi.org/10.3390/antiox12111959
Burk RF, Hill KE (2009) Selenoprotein P—expression, functions, and roles in mammals. Biochimica et Biophysica Acta (BBA)-General Subjects 1790(11):1441–1447
Chan PJ, Corselli JU, Jacobson JD, Patton WC, King A (1999) Spermac stain analysis of human sperm acrosomes. Fertil Steril 72:124–128. https://doi.org/10.1016/S0015-0282(99)00201-0
Di Iorio M (2014) Cryopreservation of rabbit semen: effectiveness of different permeable and non-permeable cryoprotectants on post-thaw sperm quality and reproductive performances. Thesis, university of Molise, Italy
Edens FW, Sefton AE (2009) Sel-Plex® improves spermatozoa morphology in broiler breeder males. Int J Poult Sci 8:853–861
El-Azzazi F, Yaseen M, Ali E, Khalil H (2016) Effect of age and vitamin E with selenium administration on testicular weight, some hematological and biochemical parameters of New zealand white rabbit bucks. Egypt Poult Sci J 36:655–668. https://doi.org/10.21608/epsj.2016.298532
El-Gindy YM (2022) Improvement in quality and storage ability of rabbit semen by using black or thyme seed as dietary supplementation. J of Anim Physiol and Anim Nutr 106:642–654. https://doi.org/10.1111/jpn.13596
Ener K, Aldemir M, Işık E, Okulu E, Ozcan MF, Uğurlu M, … Özayar A (2016) The impact of vitamin e supplementation on semen parameters and pregnancy rates after varicocelectomy: a randomised controlled study. Andrologia 48: 829–834. https://doi.org/10.1111/and.12521
Evans G, Maxwell WC (1987) Salamons’ artificial insemination of sheep and goats (No. Ed. 2). Butterworths, Sydney, Australia
Fadl AM, Ghallab AM, Abou-Ahmed MM (2019) Quality assessment of cryopreserved New Zealand white rabbit spermatozoa in INRA-82 extender containing different cryoprotectants. World Rabbit Sci 27:77–83. https://doi.org/10.4995/wrs.2019.10892
Fadl AM, Ghallab ARM, Abou-Ahmed MM, Moawad AR (2021) Melatonin can improve viability and functional integrity of cooled and frozen/thawed rabbit spermatozoa. Reprod Domest Anim 56:103–111. https://doi.org/10.1111/rda.13853
Fadl AM, El-Shahat KH, Hashem MF (2023) Effect of pentoxifylline on the testicular hemodynamic, volume, testosterone, nitric oxide levels and semen quality in Ossimi rams during non-breeding season. Theriogenology 209:126–133. https://doi.org/10.1016/j.theriogenology.2023.06.029
Fischer B, Chavatte-Palmer P, Viebahn C, Navarrete Santos A, Duranthon V (2012) Rabbit as a reproductive model for human health. Reproduction 144(1):1–10. https://doi.org/10.1530/REP-12-0091
Gouda N, El Kelawy H, Abd El Rahim M, El-Gaafary N, Ibrahim H (2021) Effect of treatment with nano-se and vitamin E on semen quality and some blood parameters of buck rabbits. J Prod Dev 26:903–922. https://doi.org/10.21608/jpd.2021.203967
Hong Z, Hailing L, Hui M, Guijie Z (2009) Effect of vitamin E supplementation on development of reproductive organs in Boer goat. Anim Rep Sci 113:93–101. https://doi.org/10.1016/j.anireprosci.2008.05.076
Hong Z, Hailing L, Hui M, Guijie Z, Leyan Y, Dubing Y (2010) Effect of vitamin E supplement in diet on antioxidant ability of testis in Boer goat. Anim Rep Sci 117:90–94. https://doi.org/10.1016/j.anireprosci.2009.03.016
Hosny NS, Hashem NM, Morsy AS, Abo-elezz ZR (2020) Effects of organic selenium on the physiological response, blood metabolites, redox status, semen quality, and fertility of rabbit bucks kept under natural heat stress conditions. Front Vet Sci 7:290. https://doi.org/10.3389/fvets.2020.00290
Ippoushi K, Ito H, Horie H, Azuma K (2005) Mechanism of inhibition of peroxynitrite-induced oxidation and nitration by [6]-gingerol. Planta Med 71:563–566
Kamel K (2012) The effect of dietary organic selenium and folic acid supplementation on productive and reproductive performance of male rabbits under heat stress conditions. Egypt Poult Sci 32:43–62
Kessopoulou E, Powers HJ, Sharma KK, Pearson MJ, Russell JM, Cooke ID, Barratt CLR (1995) A double-blind randomized placebo cross-over controlled trial using the antioxidant vitamin E to treat reactive oxygen species associated male infertility. Fertil Steril 64:825–831
Khan R, Rahman Z-U, Javed I, Muhammad F (2012) Effect of vitamins, probiotics and protein on semen traits in post-molt male broiler breeders. Anim Reprod Sci 135:85–90
Lewis SE, Boyle PM, McKinney KA, Young IS, Thompson W (1995) Total antioxidant capacity of seminal plasma is different in fertile and infertile men. Fertil Steril 64:868–870. https://doi.org/10.1016/s0015-0282(16)57870-4
Luo H, Jia Z, Zhu S, Ding J (2004) Effect of vitamin E on the qualities of fresh and frozen-thawed ram semen. China Herb 5:14–16
Mahmoud GB, Abdel-Raheem SM, Hussein HA (2013) Effect of combination of vitamin E and selenium injections on reproductive performance and blood parameters of Ossimi rams. Small Rum Res 113:103–108. https://doi.org/10.1016/j.smallrumres.2012.12.006
Malaniuk P, Lukaszewicz E (2006) Effect of feed supplementation with organic selenium and vitamin E on quantitative and qualitative characteristics of Japanese quails (Coturnix japonica). ZeszNauk UP Wroclawiu Biol Hod Zw 548:99–109
Mannucci A, Argento FR, Fini E, Coccia ME, Taddei N, Becatti M, Fiorillo C (2022) The impact of oxidative stress in male infertility. Front Mol Biosci 8:799294
Meshreky SZ, Metry GH (2000) Effect of vitamin E and/or selenium on reproductive performance of New Zealand and White Baladi black doe rabbit under climate conditions of middle Egypt, pp 6–9 in Proc. Egyptian Soc. Anim. Prod., Alexandria, Egypt
Moslemi M, Tavanbakhsh S (2011) Selenium-Vitamin E supplementation in infertile men: Effects on semen parameters and pregnancy rate. Int J Gen Med 4:99–104. https://doi.org/10.2147/IJGM.S16275
Mostafa S, Elsyed I, Hassan A, Hassan A (2019) Effect of vitamin E-selenium supplementation on some semen quality traits of Muscovy drakes. Arab Univ J Agric Sci 27:1627–1636. https://doi.org/10.21608/ajs.2019.12254.1022
Oda SS, El-Maddawy ZKh (2012) Protective effect of vitamin E and selenium combination on deltamethrin-induced reproductive toxicity in male rats. Exp Toxicol Pathol 64:813–819. https://doi.org/10.1016/j.etp.2011.03.001
Sabetian S, Jahromi BN, Vakili S, Forouhari S, Alipour S (2021) The effect of oral vitamin e on semen parameters and IVF outcome: a double-blinded randomized placebo-controlled clinical trial. BioMed Res Inter 2021:6. https://doi.org/10.1155/2021/5588275
Saddein E, Haghpanah T, Nematollahi-Mahani SN, Seyedi F, Ezzatabadipour M (2019) Preventative effects of vitamin E on testicular damage and sperm parameters in the first-generation mice pups due to pre- and postnatal mancozeb exposure. J Toxicol 4763684. https://doi.org/10.1155/2019/4763684
Salma U, Gill HK, Keith LG, Tilmon S, Jones CA, Sobti A, Patel A (2011) Male subfertility and the role of micronutrient supplementation: clinical and economic issues. J Exp Clin Assist Reprod 8:1
Sharlip ID, Jarow JP, Belker AM, Lipshultz LI, Sigman M, Thomas AJ, ... Sadovsky R (2002) Best practice policies for male infertility. Fertil Steril 77(5):873–882
Shetaewi MM (1998) Efficacy of dietary high levels of antioxidant vitamins C and E for rabbits subjected to crowding stress. Egyptian J Rabbit Sci 8:95–112
Smith JT, Mayer DT (1955) Evaluation of sperm concentration by the hemacytometer method. Comparison of four counting fluids. Fertil Steril 6:271–275
Swierstra EE, Foote RH (1965) Duration of spermatogenesis and spermatozoon transport in the rabbit based on cytological changes, DNA synthesis and labeling with tritiated thymidine. Am J Anat 116:401–412
Thuwanut P, Srisuwatanasagul S, Wongbandue G, Tanpradit N, Thongpakdee A, Tongthainan D, Manee-In S, Chatdarong K (2013) Sperm quality and the morphology of cryopreserved testicular tissues recovered post-mortem from diverse wild species. Cryobiology 67:244–247
Ursini F, Heim S, Kiess M, Maiorino M, Roveri A, Wissing J, Flohé L (1999) Dual function of the selenoprotein PHGPx during sperm maturation. Science 285:1393–1396
Van Haaften RIM, Haenen GRMM, Evelo CTA, Bast A (2003) Effect of vitamin E on glutathione-dependent enzymes. Drug Metabol Rev 35:215–253. https://doi.org/10.1081/DMR-120024086
Ventura M, Melo M, Carrilho F (2017) Selenium and Thyroid Disease: From Pathophysiology to Treatment. Int J Endocrinol 1297658. https://doi.org/10.1155/2017/1297658
Vidament M, Ecot P, Noue P, Bourgeois C, Magistrini M, Palmer E (2000) Centrifugation and addition of glycerol at 22 ℃ instead of 4–8 ℃ improve post-thaw motility and fertility of stallion spermatozoa. Theriogenology 54:907–920. https://doi.org/10.1016/S0093-691X(00)00401-5
Wang D, Jang YD, Rentfrow GK, Azain MJ, Lindemann MD (2022) Effects of dietary vitamin E and fat supplementation in growing-finishing swine fed to a heavy slaughter weight of 150 kg: II. Tissue fatty acid profile, vitamin E concentrations, and antioxidant capacity of plasma and tissue. J Anim Sci 100:184. https://doi.org/10.1093/jas/skac184
Yousef M, Abdallah G, Kamel K (2003) Effect of ascorbic acid and vitamin E supplementation on semen quality and biochemical parameters of male rabbits. Anim Reprod Sci 76:99–111
Zeidan AEB, Solouma GMA, El-Nenaey MH, Shoeib MS, EL-Taher M (2006) Reproductive activity of the heat-stressed rabbit bucks and its improvement using vitamin e and selenium under subtropical Egyptian condition. Assiut Vet Med J 52(108):360–397
Zhu Z, Fan X, Lv Y, Zhang N, Fan C, Zhang P, Zheng W (2015) Vitamin E analogue improves rabbit sperm quality during the process of cryopreservation through its antioxidative action. PLoS ONE 10:e0145383
Funding
Open access funding provided by The Science, Technology & Innovation Funding Authority (STDF) in cooperation with The Egyptian Knowledge Bank (EKB). This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
Author information
Authors and Affiliations
Contributions
AF, AS and HS wrote the main manuscript text and AF did the statistcial analysis and prepared figures and tables. All authors reviewed the manuscript.
Corresponding author
Ethics declarations
Ethics approval
This study was performed in line with the principles of the Ethics Committee of Faculty of Veterinary Medicine, Cairo University, Egypt (Vet CU 03162023751).
Competing interests
The authors declare no competing interests.
Additional information
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
About this article
Cite this article
Fadl, A.M., Samir, H. & Shahat, A.M. Repeated injections of vitamin E and Se improves testicular morphology, testosterone and in vitro and in vivo sperm fertility in subfertile rabbits. Vet Res Commun (2024). https://doi.org/10.1007/s11259-024-10439-4
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s11259-024-10439-4