The Effect of Adding Different Levels of Reduced Glutathione to Extender on the Quality of Cooled Ring-Necked Pheasant Semen

Aim: Artificial propagation of ring-necked pheasant through semen preservation is of significance, as this species is facing enormous threats in its natural habitat. Semen preservation inevitably induces oxidative stress, and exogenous antioxidants need to be investigated for the preservation of ring-necked pheasant semen. Therefore, the current study was conducted to investigate the role of glutathione (GSH) in extender on the liquid storage of ring-necked pheasant semen. Materials and Methods: Semen was collected from 10 sexually mature males, evaluated for sperm motility, and pooled. Pooled semen was aliquoted for dilution with Beltsville poultry semen extender (1:5) at 37°C having GSH levels of 0.0 mM (Control), 0.2, 0.4, 0.6, and 0.8 mM. Extended semen was gradually cooled to 4°C and stored in a refrigerator (4°C) for 48 hours. Semen quality, that is, sperm motility, membrane integrity, viability, acrosomal integrity, and DNA integrity, was assessed at 0, 2, 6, 24, and 48 hours. Results: Sperm motility (%), plasma membrane integrity (%), viability (%), and acrosomal integrity (%) were recorded higher (p < 0.05), whereas DNA fragmentation (%) was recorded lower in extender supplemented with 0.4 mM GSH up to 48 hours of storage compared with 0.2, 0.6, and 0.8 mM GSH concentrations and control. Conclusion: It is concluded that 0.4 mM GSH in extender improves sperm quality parameters of ring-necked pheasant during liquid storage up to 48 hours at 4°C.

Effects of age, body weight, semen collection frequency and holding duration on semen traits of broiler breeder reared under different housing systems

Semen traits play the vital role in determining the fertility of a broiler breeder flock; however, it can be influenced by several factors. This experiment was carried out to assess some of these factors affecting the semen. A total of 89 male birds and 960 hens of 20-week-old broiler breeder (2215 g ± 7.5%) were divided into two main groups; one was kept in cages (AIC) and another group was kept on deep litter floor (AIF), while both these groups were subjected to AI. The male birds of aforementioned groups (44 males and 480 females) were further divided into 4 sub-groups (11 males and 120 females) to execute different semen collection frequencies i.e., 2, 3, 4, and 5th days' interval. The impact of time duration between semen collection and insemination on sperm kinematics was monitored. The quantitative and qualitative analysis of semen including sperm concentration and sperm kinematics of the collected semen was conducted through a computer-assisted sperm analyzer (CASA) and ONGO machine (working on the CASA principle). Resultantly, the data revealed that the studied parameters of semen were deteriorated with the progression of age of male birds, while the group of males with standard body weight produced the best semen quantitatively and qualitatively followed by overweight particularly during the post peak phase (46-65 = 20 weeks). Although the 3rd day, semen collection frequency was found better for quality, the higher quantity of semen was achieved when males were being collected at the intervals of 4th and 5th day respectively regardless of housing systems. Significant decline in sperm kinematics was recorded with the progression of semen holding duration at the temperature of poultry farm. Furthermore, the highest contamination of E. coli, Salmonella, and Mycoplasma gallisepticum was recorded in the reproductive tract of hens and semen of the AIF group as compared to AIC. Thus, conclusion can be settled that the semen properties are significantly affected by age, body weight, and semen collection intervals in both housing systems, while sperm kinematics is being disrupted with the progression of holding duration. Although housing systems could affect the semen insignificantly, yet lesser contamination was recorded in semen and in the reproductive tract of hens of AIC.

Advances in storage of poultry semen

Semen cryopreservation is a key biotechnological strategy used to preserve and protect genetic resources, which are subject to increasingly serious reductions in some species, and to protect animal biodiversity. Assisted reproductive techniques, however, are still not utilized to the same extent in avian species to the extent that occurs in mammals. The reasons for this situation are described in this review. The content of this paper is focused on current poultry preservation systems, published since 2010, and new strategies that are very promising for preserving avian genetic resources. Two major types of storage technologies which are utilized for avian sperm preservation, liquid storage and cryopreservation, are emphasized. The issues on which there is a focus includes supplementation of avian extenders with various compounds prior to the preservation period, use of cryoprotectants and fertility results when there were in vitro sperm evaluations. Results from recent studies indicate there are opportunities to improve the quality of bird semen after preservation. It is obvious that cryo-diluent composition may be the most important factor for development of efficacious cryopreservation methods for avian semen.

RhoA improves cryopreservation of rooster sperm through the Rho/RhoA-associated Kinase/cofilin pathway

Cryopreservation of rooster sperm leads to relatively low semen quality due to cytoskeletal damage during the freeze-thawing process. This study aimed to explore how the addition of RhoA recombinant protein affected the viability and subcellular structure of rooster sperm after freeze-thawing and elucidated the molecular mechanisms of sperm cryopreservation. Semen quality and acrosome integrity testing revealed that the addition of 0.5 μg/mL RhoA recombinant protein to the cryoprotectant fluid significantly increased sperm motility, survival rate, linearity, straight-line velocity, and acrosome integrity after freeze-thawing (P < 0.05). Ultrastructure analysis of cryopreserved sperm showed structural damage to the sperm plasma membrane, nuclear membrane, and tail. However, compared to the control, these structural changes were reduced upon the addition of RhoA recombinant protein to the cryoprotective fluid (P < 0.05). Western blotting revealed that the expression of Rho/RhoA-associated kinase and p-cofilin was increased, and cofilin expression was decreased after sperm cryopreservation with recombinant RhoA protein. Treatment with Y-27632, a ROCK antagonist, suppressed ROCK and p-cofilin expression and decreased semen quality, acrosome integrity, and ultrastructure integrity. In summary, we have demonstrated a cryoprotective effect in spermatozoa involving the Rho/ROCK pathway during freeze-thawing. Furthermore, the addition of 0.5 μg/mL RhoA recombinant protein to the cryoprotective fluid improved rooster semen quality and subcellular structural homeostasis after freeze-thawing via the Rho/ROCK pathway. This pathway may regulate the dynamic reorganization of the actin cytoskeleton by regulating the cofilin phosphorylation.

Freezing chicken semen: Influence of base medium osmolality, cryoprotectants, cryoprotectant concentration, and cooling rate on post-thaw sperm survival

A classical chicken semen diluent (Lake's 7.1 diluent) was modified to have lowered osmolalities (ranging from 290-410 mOsm/kg). The modified medium with physiological osmolality of 325 mOsm/kg allowed cold storage of fresh semen for several days with very little loss of membrane integrity and motility, while high osmolalities inhibited motility. This modified medium was then used as base for freezing medium to test effects of the type and concentration of cryoprotective agent (CPA), and the cooling rate (CR). A number of CPAs (methylformamide, methylacetamide, dimethylformamide (DMF), dimethylacetamide (DMA), diethylformamide, and propylene glycol) were first compared by freezing semen with 0.6 mol/l of the respective CPA at a cooling rate of 250°C/min. Post-thaw motility and membrane integrity were highest with DMA and DMF. Finally, in more detailed factorial experiments, semen from individual cocks or pooled semen was frozen using CRs of 4, 50, 250, and 440 °C/min and DMA concentrations ([DMA]) of 0.4, 0.6, 1.0, and 1.5 mol/l. Straws from each semen sample x treatment combination were divided for semen assessment at three different research groups for sperm motility, membrane integrity, kinked tails, and DNA fragmentation, using microscopy, computer assisted motility analysis, and flow cytometry. There were clear effects of both CR and [DMA] and their interaction. CRs 50 and 250°C/min gave best post-thaw sperm performance. Higher DMA concentrations gave better post-thaw membrane integrity, but concentrations above 1.0 mol/l can decrease sperm velocity or even inhibit sperm motility. Therefore [DMA] may best be 0.6-1.0 mol/l at a CR of 50-250°C/min.

The effects of caffeine on the motility and viability of stallion spermatozoa at different temperature conditions

The purpose of this study was to evaluate the dose- and time-dependent effect of caffeine treatment on the motility and viability of stallion spermatozoa at different temperatures. Six dose groups (A to F) were established with changing caffeine concentrations (from 0.625 to 10 mg/mL). The control samples were prepared by diluting the ejaculate only with physiological salt solution. The samples were examined after 0, 1, 2 and 3 h of incubation at 5 °C and 37 °C. The motility parameters were evaluated by Computer Assisted Semen Analyzer (CASA) system, and the viability was assessed by the mitochondrial toxicity test at the end of the incubation. A positive effect of the lowest tested caffeine concentration on the motility parameters was observed throughout the incubation period at 5 °C. At the end of the 3h incubation, the viability in every sample in these groups, treated with any caffeine concentration, showed lower values compared to the control. At the higher incubation temperature (37 °C), caffeine positively affected the motility in samples B (P < 0.05) and D, E, F (P < 0.001) after 3 h of incubation; however, the viability showed a slightly decreasing tendency. Our results suggest that caffeine, in an optimal concentration, may be used as a component of stallion semen extenders.

Spermatozoa Survival in Egg Yolk-Based and Soybean-Based Extenders at Ambient and Chilling Temperature in Domestic Turkeys (Meleagris gallopavo)

Populations of many galliform species have declined mainly due to habitat loss and over-hunting, notably the Congo peacock, which has been classified as a vulnerable species by the International Union for Conservation of Nature (IUCN). The domestic turkey, being a species of least concern, which has been reported to be closely related to peacocks, could serve as a model for the optimization of assisted reproductive technologies for the Congo peacock. This study was aimed at developing a suitable turkey semen extender for artificial insemination in field conditions. Semen was collected using the dorso-abdominal massage technique from seven turkey toms and analyzed. Ejaculates with >70% motility and >80% live spermatozoa were pooled and divided into four aliquots (four treatments). Each of the four treatments was extended in a soybean-based extender or an egg yolk-based extender, with or without L-ascorbic acid. Two liquid preservation protocols (ambient temperature (35 °C) and chilled (4 °C)) were employed, and quality parameters including motility, viability and morphology were evaluated. The results show that the two extenders were similar with regard to semen quality parameters, and L-ascorbic acid supplementation of the turkey semen extenders improved semen quality during liquid storage.

Assessing different liquid-storage temperatures for rooster spermatozoa

Although liquid-storage is extensively used in poultry, there are still questions on how sperm physiology is affected and to what extent sperm functions are disrupted by storage temperature and time. There, therefore, was investigation of storage temperature and durations on multiple semen variables. The storage at 37 °C was the most damaging, affecting values for several variables within 4 h of storage, whereas most differences occurred between 5 and 25 °C after 8 h. Progressive motility and mitochondrial function started to decrease within 2 h at 25 and 37 °C, and within 4 h at 5 °C. Acrosomal damage only occurred in samples at 37 °C. Eosin-negrosin staining indicated there was damage to the plasma membrane at 37 °C, however, with use of propidium iodide there were differences between 5 and 25 °C following 24 h. Temperatures of 5 and 25 °C resulted in similar curves for chromatin dispersion although chromatin integrities differed with storage for periods longer than 4 h. At 37 °C, results using both chromatin evaluations indicated there was damage after 2 h of incubation. Oxidative stress at 5 and 25 °C was similar when there was 24 h of storage. Intriguingly, there were no interaction between temperature and storage duration for peroxidized sperm membrane and total peroxidation status. These findings indicated that with a prolonged storage at 5 °C there were not marked changes in chicken spermatozoa, whereas at 25 °C there did not appear to be sperm damage occurring as a result of short-term storage.

Effect of semen extenders and storage time on quality of Muscovy duck (Cairina moschata) drake semen during the entire reproductive season

Avian semen dilution with appropriate extender allows to prolong the fertilizing ability of sperm stored in vitro. In the present study, the impact of extenders and time of storage on morphology of Muscovy duck (Cairina moschata) drake semen were examined. Semen was collected twice a week, using male stimulation by a female method, from 12 adults (29 weeks old) drakes kept individually in cages, under controlled environmental conditions. Freshly collected, pooled ejaculates were divided into three part: neat undiluted sample, and diluted 1:1 with Schramm (SCH) or Watanabe (W) extender and stored at 4°C. Morphological examination of all samples was conducted after dilution and then, after 3 and 6 hr of storage. The storage of undiluted semen caused decrease (p ≤ .01) in live morphologically normal sperm, from 79.73% in the freshly collected ejaculates to 55.75% and to 12.12% after 3 and 6 hr of storage, respectively (average calculated for the entire reproductive season). In the semen diluted with Schramm's extender the adequate values attained 86.84, 79.65 and 61.66%, and using Watanabe extender 84.77, 83.58 and 75.25%, respectively. The period of semen storage and the type of extender caused significant (p ≤ 0,05; p ≤ 0,01) changes in sperm morphology. The longer period of storage contributed to the decrease in number of morphologically normal sperm, whereas their content in Watanabe extender after 3 and 6 hr of storage was higher (p ≤ .01) than in semen diluted in Schramm extender.

Effect of semen extenders on viability of ISA Brown and Hubbard Flex roosters' sperm stored for 24 h

Artificial insemination is used in almost 95% of turkey reproductive flocks and is becoming more important in chickens, particularly broiler breeders, as well as in assisted reproduction of wild birds kept in breeding centers. Diluted semen is recommended for artificial insemination. Pooled semen samples collected twice a week by dorso-abdominal massage from 2 chicken lines: laying-ISA Brown (ISA-B) and meat type-Hubbard Flex (H-F) were divided into 5 parts: neat semen and diluted in 1:2 ratio with 4 extenders: basic EK; EK + 1 μg/mL organic selenium and 8 μg/mL vitamin E; EK + 10 mg/mL of royal jelly; and EK + 0.25 g/mL of lyophilized bovine colostrum. Diluted semen samples were evaluated after 15 min and then 24 h storage at 4°C. Sperm concentration, motility, motility parameters (with Sperm Class Analyzer), and morphology were evaluated in the neat semen, whereas in diluted and stored samples, the last 3 traits were determined. In case of both lines, dilution did not affect (P > 0.05) the number of live normal cells (78.0-81.1% in ISA Brown and 73.8-68.7% in Hubbard Flex) in relation to neat semen; however, bovine colostrum addition increased (P < 0.05) the percentage of bulb head sperm (5.7 vs. 10.0% and 12.1 vs. 17.6%, for ISA and Hubbard, respectively) and decreased sperm motility (67.4 vs. 92.9% and 67.3 vs. 98.5% for ISA and Hubbard). The 24 h storage of neat semen and semen diluted with colostrum caused (P < 0.05) the unfavorable changes in all evaluated traits and both chicken lines, whereas semen dilution with remaining extenders decreased the percentage of live normal cells (by 18.8-23.4% ISA and by 20.9-25.5% Hubbard) but did not affect sperm motility (81.5-87.6% for ISA and 81.1-96.6% for Hubbard). Sperm motility and motility parameters depended both on the extender and chicken line.

Comparison of TNC and standard extender on post-thaw quality and in vivo fertility of Thai native chicken sperm

Semen extender has a vital role in preservation of sperm cells properties in terms of sperm viability, motility, acrosome integrity, and mitochondrial membrane potential. The objective of the present study was to evaluate a new extender, known as Thai native chicken (TNC) extender compared to BHSV-based and modified Sasaki extenders for freezing chicken semen. Semen from Thai native roosters was collected, pooled, and randomly divided into three groups. Semen was frozen with a simple freezing method using nitrogen vapor and dimethylformamide. In the first experiment, post-thaw motion parameters, viability, acrosome integrity, mitochondrial function, and lipid peroxidation levels were analyzed using computer-assisted sperm analysis, propidium iodide, fluorescein isothiocyanate-conjugate peanut agglutinin, JC-1, and the thiobarbituric acid reaction. Results showed that the type of extender had no effect on the percentage of total motile and curvilinear velocity. The percentage of progressive motile, straight-line velocity, and average path velocity of post-thawed semen were significantly lower in TNC compared to the modified Sasaki extender. However, the percentages of post-thawed acrosome integrity and active mitochondria were significantly higher in TNC extender (P < 0.05). For the second experiment, semen was thawed by using each of extenders thereafter, was inseminated to 48-layer breeder hens to determine the fertility rate. Among the three extenders used, the highest fertility rate was found in TNC extender. In conclusion, TNC extender can be recommended as an appropriate and useful cryopreservation media for native chicken semen since it maintains the quality of rooster semen and fertility after freezing and thawing process.

Quercetin attenuates H2 O2 -induced toxicity of rooster semen during liquid storage at 4°C

Current study was carried out to examine the protective effects of quercetin against toxicity induced by hydrogen peroxide in rooster semen in vitro. Semen samples were collected from ten roosters (Ross 308 broiler breeder males, 32 weeks old) twice a week by abdominal massage method. Samples with ≥70% progressive motility were selected, pooled, diluted and used for the study. Experimental groups consisted of negative control, control that received solvent of quercetin, H₂ O₂ (40 μM) and combination groups which incubated with constant dose of H₂ O₂ (40 μM) plus various levels of quercetin (20, 40 and 80 μM). Measurement of total hydroperoxide (HPO), malondialdehyde (MDA), nitric oxide (NO), total antioxidant capacity (TAC) and superoxide dismutase activity as well as routine sperm tests were done at 0, 24 and 48 hr of storage at 4°C. Results revealed that exposure to hydrogen peroxide significantly increased HPO (138.43 ± 7.32 vs. 66.08 ± 3.97 μmol/g protein), MDA (7.21 ± 0.08 vs. 5.71 ± 2.16 μmol/g protein) and NO (0.367 ± 0.013 vs. 0.215 ± 0.011 μmol/g protein) levels and decreased sperm progressive motility (27.28 ± 1.21 vs. 47.49 ± 1.29%), and amounts of TAC (11.49 ± 0.39 vs. 15.70 ± 0.79 mmol/g protein) compared to control at 24 hr (p < 0.05). Changes at mentioned variables were repeated at 48 hr of storage. Also, co-administration of quercetin (especially at 40 and 80 μM) with hydrogen peroxide restored the toxic effects of hydrogen peroxide on rooster semen parameters such as primary and secondary lipid peroxidative indicators and other evaluated variables. The study concluded that rooster semen enrichment with quercetin would protect lipid peroxidative and nitrosative hydrogen peroxide-mediated damage during cold liquid storage of rooster semen.

Post-release breeding of translocated sharp-tailed grouse and an absence of artificial insemination effects

Context Translocation has become a widely used method to restore wildlife populations following extirpation. For some species, such as lekking grouse, which breed at traditional mating grounds, reproduction is linked to culturally established geographic locations. Cultural centres are lost upon extirpation, making restoration into otherwise rehabilitated habitats especially challenging. The process by which species with culturally dependent reproduction sometimes become re-established is poorly understood and merits investigation to improve conservation strategies. Historically, population restoration of North American lekking grouse (Tympanuchus spp. and Centrocercus spp.) via translocation has yielded poor results, in part because translocation sites lack leks, culturally determined breeding locations for which breeding adults form a high degree of philopatry. Columbian sharp-tailed grouse (Tympanuchus phasianellus columbianus; CSTG) occurs in &lt;10% of its historic range, but the existence of rehabilitated historic habitat provides for the potential of population restoration via translocation. Aims We reintroduced CSTG to vacant habitat in north-central Nevada, USA, from 2013 to 2017, with concordant goals of promoting females to nest and males to lek. We tested the utility of performing artificial insemination (AI) on females before translocation and we conducted paternity analyses to understand male reproduction. Methods We monitored females for the effects of AI on nest initiation, nest survival and egg fertility. We used post-hatch extra-embryonic membranes and other tissues to evaluate paternity of chicks produced at the restoration site. Key results Artificial insemination had no effect on female survival or nest initiation, and did not fertilise any eggs within nine sampled clutches (n=102 eggs). Most paternity was attributable to male residents that had survived for ≥1 year at the restoration site before the arrival of translocated females. Conclusions Artificial insemination neither aided nor harmed female reproduction. A small number of translocated, resident adult males sired reproduction following female release. Implications The presence of resident males at restoration sites may be more likely to result in post-translocation reproduction than is pre-translocation AI. Restoring CSTG to vacant habitat should focus on translocating females into suitable nesting habitat while simultaneously ensuring that reproductively capable males are available within or adjacent to the nesting habitat.

Investigations on different Semen Extenders for Cockatiel Semen

The aim of the present study was the modification and evaluation of three different semen extenders for cockatiel semen in order to achieve a long survival time for transport, examination purpose and for potential cryopreservation, respectively. Therefore, individual and pooled semen samples of 30 cockatiels (Nymphicus hollandicus) were investigated for pH and osmolality values and subsequently pH and osmolality values of the semen extenders were adjusted to those values in the semen. Pooled semen samples were then partitioned into four equal parts and diluted with the three different semen extenders in 1:4 and 1:8 dilution. 1 % glucose-Ringer’s solution was used as control, respectively. A total of 64 incremental diluted semen samples were obtained for investigation. Each dilution was investigated regarding sperm motility immediately after dilution and another four times every 30 minutes. Sperm viability was evaluated 0 and 120 minutes after dilution via eosin B-stain on the diluted semen samples and in pure semen samples. Additionally, the fluorescence stain SYBR® Green/propidium iodide was used to assess sperm viability. The results indicate that cockatiel spermatozoa are highly sensitive to variations in pH and osmolality, requiring adjustment of commercial diluents to pH = 7.42 and osmolality = 300 mOsm/kg. Modified Lake diluent maintained higher viability and motility than other diluents tested. Sperm morphology was indicated to be least adversely affected by modified Lake diluent in 1:4 concentration compared to other semen extenders and concentrations used.

The use of two staining methods for identification of spermatozoon structure in roosters

Many of the methods used to stain semen result in very pronounced coloring of the sperm, but unfortunately they do not distinguish their individual structures, which play a key role in the fertilization process. Hence the aim of this study was to identify sperm structures using two staining techniques in the semen of roosters from breeding flocks. The subject of the study was the sperm of roosters from a Ross 308 breeding flock. To capture the differences in the dimensions of sperm subjected to the effect of different chemical substances in dyes, microscope slides were stained by two techniques: with an AgNO3 solution and by a differential method (eosin-nigrosin test). Assessment was made of the degree of coloration and the number of details that could be identified in the morphological structure of the sperm. The use of AgNO3 allowed accurate identification of the acrosome, nucleus, and midpiece, which were visible in the slides stained with eosin-nigrosin, but only in dead spermatozoa. The AGNO3 staining technique used in this study reveals the cell nucleus within the head and can be an alternative method to analysis with a scanning electron microscope. This staining technique can be used to stain sperm structures that cannot be seen in other methods of slide preparation, which means that it can be considered for routine use in assessing the fertility of roosters in breeder flocks.

Generation of gene edited birds in one generation using sperm transfection assisted gene editing (STAGE)

Generating transgenic and gene edited mammals involves in vitro manipulation of oocytes or single cell embryos. Due to the comparative inaccessibility of avian oocytes and single cell embryos, novel protocols have been developed to produce transgenic and gene edited birds. While these protocols are relatively efficient, they involve two generation intervals before reaching complete somatic and germline expressing transgenic or gene edited birds. Most of this work has been done with chickens, and many protocols require in vitro culturing of primordial germ cells (PGCs). However, for many other bird species no methodology for long term culture of PGCs exists. Developing methodologies to produce germline transgenic or gene edited birds in the first generation would save significant amounts of time and resource. Furthermore, developing protocols that can be readily adapted to a wide variety of avian species would open up new research opportunities. Here we report a method using sperm as a delivery mechanism for gene editing vectors which we call sperm transfection assisted gene editing (STAGE). We have successfully used this method to generate GFP knockout embryos and chickens, as well as generate embryos with mutations in the doublesex and mab-3 related transcription factor 1 (DMRT1) gene using the CRISPR/Cas9 system. The efficiency of the method varies from as low as 0% to as high as 26% with multiple factors such as CRISPR guide efficiency and mRNA stability likely impacting the outcome. This straightforward methodology could simplify gene editing in many bird species including those for which no methodology currently exists.

Effect of season and age on Indian red jungle fowl (Gallus gallus murghi) semen characteristics: A 4-year retrospective study

The reproductive potential of the adult males is expected to vary with age/season and largely differ not only in closely related avian species but even in subspecies, breeds and/or strains of the same species. Thus, it is pre-requisite to have knowledge of seminal parameters to achieve maximum production potential of at-risk species for ex situ in vitro conservation programs. A 4-year study was designed to evaluate the effect of age and season (spring, summer, autumn and winter) on semen characteristics of Indian red jungle fowl (Gallus gallus murghi) in a retrospective manner. Semen ejaculates (n = 1148) were regularly collected from eight adult cocks 6 to 54 months of age. Quantitative and qualitative semen parameters viz; volume (μL), concentration (1 × 10⁹ mL^-1), total sperm number per ejaculate (1 × 10⁹ mL^-1), motility (%), viability (%), plasma membrane integrity (%), acrosome integrity (%) and semen quality factor were recorded. A chronological increasing trend with age of most sperm quantitative and qualitative traits (semen volume, sperm concentration, total sperm number per ejaculate, plasma membrane integrity, viability, acrosomal integrity and semen quality factor) was observed. The highest values were observed at four years of age (P < 0.05) with the exception of sperm motility that was not affected by the age. Spring was the best season for sperm parameters viz; volume, motility, plasma membrane integrity, viability and acrosomal integrity (P < 0.05), however a remarkable sperm production was noticed all over the year. It is concluded that Indian red jungle fowl exhibits an evolution of sperm production that greatly differs in many points from other fowl sub-species. It is suggested that semen ejaculates of highest quality achieved for semen banking at the age of four year in the spring season.

Plumping fluid added to storage medium increases twofold the functional life span of fowl spermatozoa in vitro at 4°C

1. The objective of this study was to examine whether addition of plumping fluid (PF) to Lake's solution (LS) for storage of fowl spermatozoa in vitro at 4°C can prolong survival and improve the quality of spermatozoa. 2. In experiment 1, aliquots of spermatozoa were stored in vitro in LS alone and LS containing 10%, 25%, 50% and 75% (v:v) PF for 0.5, 24, 48, 72, 96 and 120 h at 4°C. After the end of each storage period, spermatozoa were evaluated for their viability, mobility and penetrability. Viability was determined using SYBR-14 and propidium iodide (PI) staining. Mobility was assessed using an Accudenz assay. Penetrability was assessed using spermatozoa-inner perivitelline layer (IPL) interaction assay. 3. In experiment 2, aliquots of spermatozoa were stored in vitro in LS alone and LS containing 25% and 50% (v:v) PF for 0.5, 24, 48 and 72 h at 4°C, and then fertility of the spermatozoa was evaluated using intravaginal artificial insemination (AI) in hens. 4. Storage of spermatozoa in LS alone resulted in loss of viability, mobility, penetrability and fertility within 48 h. In contrast, no loss of viability and penetrability was observed for the spermatozoa stored for 48, 96, 72 and 48 h in LS containing 10%, 25%, 50% and 75% (v:v) PF, respectively. In particular, fertilising capacity was not lost for the spermatozoa stored in the presence of 25% or 50% PF in LS for 48 and 24 h, respectively. 5. In conclusion, these findings demonstrated that in vitro exposure of fowl spermatozoa to PF during hypothermic storage in LS prolonged spermatozoa survival. A 25% (v:v) level of inclusion of PF in LS may be effective for the improvement of viability, penetrability and fertilising ability of the stored spermatozoa.

Extending the viability of emu spermatozoa during in vitro storage by manipulation of temperature and diluent potassium concentration

1. Survival of emu spermatozoa during in vitro storage is not affected by increasing the extracellular [K(+)] to the point where it does not adversely affect spermatozoa function. 2. In three experiments, the effects were studied of [K(+)] in a diluent in the range 12·5-80 mM/l on emu spermatozoa survival for up to 48 h at 5, 10 or 20°C. 3. At the end of the storage period, spermatozoa viability, motility, fertilising ability and morphology were measured. 4. In Experiment 1, spermatozoa viability and morphology were adversely affected after storage (P < 0·001) only in the diluent containing 80 mM/l [K(+)] whereas spermatozoa motility decreased as [K(+)] increased from 12·5 to 80 mM/l. 5. In Experiment 2, during storage at 5°C, the spermatozoa viability was comparable among any of the diluents (standard or modified) but morphology was better (P < 0·001) in all of the modified diluents than in the standard E3 diluent. 6. In Experiment 3, after 48 h of storage in a diluent containing 40 mM/l of [K(+)], the spermatozoa functions were better preserved at 10°C than at 5 or 20°C. 7. It is concluded that a higher than physiological level of potassium can be used in a diluent without detrimental effect on emu spermatozoa survival during 48 h storage and that the best outcome was with storage at 10°C rather than 5 or 20°C.

Detection of lipid peroxidation in frozen-thawed avian spermatozoa using C(11)-BODIPY(581/591)

The aim of this study was to perform flow cytometric analysis of C11-BODIPY581/591 oxidation in fowl and geese sperm as a marker for membrane lipid peroxidation (LPO) and to establish if the cryopreservation process would make sperm membranes more susceptible to oxidative stress. The experiment was carried out on 10 meat type line Flex roosters and 10 White Koluda® geese. The semen was collected two times a week, by dorso-abdominal massage method and pooled from 10 individuals of each species. Fowl semen samples were subjected to cryopreservation using the "pellet" method and Dimethylacetamide (DMA) as a cryoprotectant. Geese semen samples were cryopreserved in plastic straws in a programmable freezing unit with Dimethyloformamide (DMF) as the cryoprotectant. A fluorescent lipid probe C11-BODIPY581/591 provided with two double bonds that are oxidized during their contact with ROS, was used for the purpose of the assessment of the LPO in freshly diluted semen samples and frozen-thawed semen samples. This probe changes its color according to its state (non peroxidized: red; peroxidized: green). Flow cytometric analysis was used to monitor these changes. The White Koluda® geese fresh semen had a higher level of LPO than the Flex fresh semen (P > 0.01). The cryopreservation of fowl semen significantly (P > 0.01) increased the percentage of live and dead spermatozoa with lipid peroxidation. In frozen-thawed semen of White Koluda® geese the percentage of live spermatozoa with LPO significantly decreased (P > 0.05) whereas significantly (P > 0.01) higher level of dead cells with LPO was observed. There were significant differences between the two studied species. After thawing, the percentage of live and dead spermatozoa with lipid peroxidation was higher in fowl semen than in geese semen (P > 0.01). In conclusion, our data clearly indicate the existence of species specific differences in susceptibility of spermatozoa to the oxidation of PUFAs in the cell membranes, where such oxidation is caused by cryopreservation. This study shows that avian spermatozoa are vulnerable to radicals and frozenthawed sperm have higher level of LPO than fresh sperm. According to our observation, fowl semen is more susceptible to LPO than geese semen.