scholarly journals 211QUALITY CHANGES IN BLUE WILDEBEEST (CONNOCHAETES TAURINUS) EPIDIDYMAL SPERMATOZOA MAINTAINED AT 4°C

2004 ◽  
Vol 16 (2) ◽  
pp. 227
Author(s):  
F. Olivier ◽  
T. Spies ◽  
F. Martinez-Pastor ◽  
D.M. Barry ◽  
P. Bartels

Wildlife management in southern Africa often involves the harvesting of animals on ranches and reserves, providing unique opportunities to collect and assess the quality of epididymal spermatozoa for possible future conservation actions. The black wildebeest (Connochaetes gnu) is facing renewed threats to its survival, including the production of fertile hybrids from crossing with the more common blue wildebeest (Connochaetes taurinus). The close relationship between the two wildebeest species allows for the blue wildebeest to be used as a model to assess epididymal sperm quality over time while maintained at 4°C. Field conditions often preclude the immediate availability of liquid nitrogen, necessitating the development of alternative short-term storage methods. All chemicals were provided by Sigma (South Africa) unless otherwise stated. Testes were harvested from 6 blue wildebeest bulls at a local game farm, Savannah, and kept at 5°C during transportation to the lab. Epididymides were dissected out and spermatozoa were flushed out of the cauda epididymis using 1mL of Tris-citrate egg yolk extender (Fraction A, Biladyl, Minitub, Germany), followed by storage at 4°C and assessment at 12h intervals. At each interval, an aliquot was removed, washed with a modified buffered HEPES solution (20mM HEPES, 355mM sucrose, 10mM glucose, 2.5mM KOH;; 400mOsm/kg, pH 7; Sigma) and visually assessed with a phase contrast microscope (×200, at 37°C) to determine the percentage of motile (MS) and progressive motile (PS) spermatozoa. In addition, plasma membrane integrity (PMI) was assessed with eosin-nigrosin staining and active mitochondrial status (MIT) assessed with an epifluorescent microscope (×400) using the fluorescent probe JC-1 (Molecular Probes, The Netherlands;; 7.5μM; 30min at 37°C). Resilience to hypo-osmotic shock was also evaluated by incubating the sample in a modified hypo-osmotic medium (100mOsmkg−1; 15min RT), and staining with PI to assess plasma membrane integrity (HOSPMI). A summary of results is presented in the table 1. The MS, MIT and HOSPMI did not decrease significantly during the 48h storage period. The only parameters that showed a significant decrease were PS and PMI (P<0.01, Kruskall-Wallis test). However, PMI showed a slow but steady decrease (13%), whereas PS underwent a significant drop (52%). In conclusion, epididymal spermatozoa from the blue wildebeest, kept at 4°C for 48h, may still be useful for some assisted-reproduction techniques. The use of spermatozoa from a common but closely related wildebeest species allows for the development of assisted-reproduction techniques that may one day aid the conservation of threatened wildebeest species. Additional research is needed to confirm these findings and to test the effect of longer storage times on spermatozoa of this species as well as closely related endangered species. Table 1 Parameters measured during the 12-h time periods (mean±SD)

2004 ◽  
Vol 16 (2) ◽  
pp. 225 ◽  
Author(s):  
A.F. Malo ◽  
F. Martinez-Pastor ◽  
F. Olivier ◽  
T. Spies ◽  
E.R.S. Roldan ◽  
...  

Epididymal spermatozoa from harvested wild animals is potentially useful for conservation purposes, as it can be used for subsequent artificial insemination or stored in Biological Resource Banks for future use. The potential of sperm banking is of particular interest for use in lion (Panthera leo) populations maintained in small National Parks, as translocation of males to effect gene-flow is often problematic, resulting in the translocated lion being killed by resident pride males. We measured the change in sperm quality over time during cool storage (at 4°C) and after thawing of samples cryopreserved at −196°C. Also, we present a correlation between sperm plasma membrane integrity and mitochondrial activity as measured by fluorescent analysis. The testes from a pride lion were removed and transported to the laboratory (at 4°C) within 6h. The epididymides were removed and both cauda epididymides were flushed with 1mL of Tris-citrate egg yolk extender (Fraction A, Biladyl, Minitub, Germany). The sample containing 2930×106 cells mL−1 was washed (20mM HEPES, 355mM sucrose, 10mM glucose, 2.5mM KOH;; 400mOsm/kg, pH 7; Sigma, South Africa) and after centrifugation (5min. at 600g), the pellet was resuspended in 0.5mL of washing solution (with 197mM NaCl instead of sucrose). One aliquot of spermatozoa was kept at 4°C and evaluated at 24h intervals for 7 days. A second aliquot of the sperm sample was extended in Tris-citrate egg yolk extender with glycerol (Fraction B, Biladyl), frozen in liquid nitrogen (LN) vapor and stored in LN. The frozen sample was later thawed and evaluated as for the cooled samples. Percentages of motile (MS) and progressive (PS) spermatozoa were assessed using a phase contrast microscope (×200; stage at 37°C). Sperm plasma membrane damage was assessed by determining the percentage of cells exhibiting red fluoresence after staining with propidium iodide (PI, 50ng/mL; 10min RT). Spermatozoa that did not stain red in PI were classified as plasma membrane intact (PMI). Resilience to hypo-osmotic shock and plasma membrane integrity were evaluated by incubating a portion of the sample in a 100mOsm/kg solution (10nM glucose, 20nM HEPES, 30nM NaCl) containing PI for 15min at room temperature. The percentage of sperm cells with active mitochondria (MIT) was determined by counting spermatozoa showing orange fluoresence over the mid-piece after staining with JC-1(7.5 uM Sigma) for 30min at 37°C. At collection, MS was 15% and did not show a significant decrease during the 7-day storage period. Initially, PS was 10% and dropped to 5% after 7 days, with values fluctuating during the storage period. Both PMI and HOSPMI were 80% on Day 1, gradually decreasing to 75% on Day 7 of storage. PMI and MIT showed a highly significant correlation (r=0.88; P=0.003; n=8). In frozen-thawed sperm samples, MS fell from a pre-freeze value of 15% to 5% after thawing. Similarly, PS fell from 10% in pre-freeze to 3% in frozen-thawed samples. Likewise, PMI, HOSPMI and MIT values were 80% and 45%, 87% and 45% and 89% and 49%, respectively. Our study showed that lion sperm PMI and MIT remained high after 7 days at 4°C. MS and PS, although low, did not vary during this same period. PI and JC-1 showed a significant correlation, suggesting that both might be affected by the same deleterious factors. Although PMI, HOSPMI and MIT values decreased approximately 40% after freezing, we feel that such sperm samples could be used for in vitro embryo production, if not by IVF, by ICSI. Of course, additional studies are needed to validate our suggestion.


2015 ◽  
Vol 29 (5) ◽  
pp. 646-651 ◽  
Author(s):  
N. Prapaiwan ◽  
T. Tharasanit ◽  
S. Punjachaipornpol ◽  
D. Yamtang ◽  
A. Roongsitthichai ◽  
...  

2009 ◽  
Vol 59 (2) ◽  
pp. 159-168 ◽  
Author(s):  
Arash Kheradmand ◽  
Majid Taati ◽  
Homayoon Babaei

AbstractAlthough ghrelin acts as a modulator of feeding behavior and energy metabolism in the central nervous system, recent studies have implicated the peripheral actions of ghrelin in reproductive tissues. Here, we investigated the effects of chronic administration of ghrelin on the motility, plasma membrane integrity and concentration of rat spermatozoa. 45-d male Wistar rats were scheduled for the study and were divided into control and treatment groups. In the treatment group, 1 nmol of ghrelin was administered as sc injection for 10 consecutive days or vehicle (physiological saline) to the control rats. Sperm collection was achieved by killing of the rats on days 15, 25 and 50 after first injection. Total sperm motility and forward progressive movement did not exhibit significant difference during the experiment, although, there was a tendency for greater motion rate on d 15 and 25 in the treated rats compared to the control group. Plasma membrane integrity (HOS-reacted spermatozoa) was significantly higher in the treated animals, especially on day 15 as well as day 25, because of possible antioxidant properties of ghrelin. This value was statistically higher on day 15 than that of day 25 (P <0.05). Likewise, there was a significant correlation between the FPM (P <0.0001, r = 0.79) and TSM (P <0.01, r = 0.52) with the HOS test percentage in the treatment group. It was not observed statistically difference in the sperm concentration between groups during all of the experimental days. In conclusion, chronic administration of ghrelin (similar to induced by energy deficiency such as fasting) increased the integrity of sperm membrane, however, the sperm motility and concentration did not display any alterations.


Reproduction ◽  
2007 ◽  
Vol 134 (1) ◽  
pp. 111-121 ◽  
Author(s):  
S Sancho ◽  
I Casas ◽  
H Ekwall ◽  
F Saravia ◽  
H Rodriguez-Martinez ◽  
...  

This study evaluated the effects of cooling, freezing and thawing on the plasma membrane integrity, kinetics and expression of two sugar transporters glucose transporter-3 and -5 (GLUT-3 and GLUT-5) in spermatozoa from Iberian boars. Semen samples were collected twice weekly from eight young, fertile Iberian boars of the ‘Entrepelado’ and ‘Lampiño’ breeds. The samples were suspended in a commercial extender and refrigerated to 17 °C for transport to the laboratory (step A), where they were further extended with a lactose–egg yolk-based extender and chilled to 5 °C (step B) prior to freezing in the presence of glycerol (3%). Spermatozoa were assessed for plasma membrane integrity and sperm motility at each of the steps, including post-thaw (step C). Aliquots were also prepared for immunocytochemical localisation of the sugar transporters (fixed and thin smears for transmission and scanning electron microscopy levels respectively) and for SDS–PAGE electrophoresis and subsequent western blotting, using the same antibodies (rabbit anti-GLUT-3 and anti-GLUT-5 polyclonal antibodies). The results showed lower percentages of progressively motile spermatozoa at step C in both breeds, while the percentage of live spermatozoa was significantly lower only in the ‘Entrepelado’ breed. The results obtained from electron microscopy clearly showed that Iberian boar spermatozoa expressed the hexose transporters, GLUT-3 and GLUT-5. The pattern of expression, in terms of location and concentration, was characteristic in each case but, in the case of isoform GLUT-5, it remained constant during the different steps of freezing–thawing protocol. These results indicate that cryopreservation affects the status of sperm cells of Iberian boars by altering the distribution of some membrane receptors and decreasing the percentage values of parameters linked to sperm quality.


2010 ◽  
Vol 13 (4) ◽  
pp. 571-579 ◽  
Author(s):  
W. Kordan ◽  
M. Lecewicz ◽  
R. Strzeżek ◽  
A. Dziekońska ◽  
L. Fraser

Effect of platelet activating factor (PAF) supplementation in semen extender on viability and ATP content of cryopreserved canine spermatozoa The aim of this study was to investigate the effect of platelet activating factor (PAF) on the quality characteristics of cryopreserved canine spermatozoa. Cryopreserved semen of 5 mixed-breed dogs was treated with different concentrations of exogenous PAF (1 × 10-3M, 1 × 10-4M, 1 × 10-5M and 1 × 10-6M) and examined at different time intervals (0, 30, 60 and 120 min). Cryopreserved semen treated without PAF was used as the control. Sperm quality was evaluated for motility (computer-assisted semen analysis, CASA), mitochondrial function (JC-1/PI assay) and plasma membrane integrity (SYBR-14/PI assay and Hoechst 33258). Also, ATP content of spermatozoa was determined using a bioluminescence assay. Treatment of cryopreserved semen with 1 × 10-3 M PAF at 120 min of incubation resulted in significantly higher total sperm motility compared with the control. It was observed that PAF-improved total sperm motility was concurrent with enhanced sperm motility patterns after treatment of cryopreserved semen. Treatment of cryopreserved semen with PAF did not improve either sperm mitochondrial function or plasma membrane integrity, as monitored by different fluorescent membrane markers. Furthermore, ATP content of cryopreserved spermatozoa was significantly higher when PAF was used at a concentration of 1 × 10-3 M compared with the control and other PAF treatments, regardless of the incubation time. The findings of this study indicated that treatment with 1 × 10-3 M PAF at 120 min of incubation rendered better quality of cryopreserved canine semen, which was associated with improved sperm motility parameters and ATP content. It can be suggested that exogenous PAF addition is beneficial as a supplement for canine semen extender used for.


2020 ◽  
Vol 15 (03) ◽  
pp. 24-29
Author(s):  
A. J. Dhami ◽  
Tapasvi M Patel ◽  
DV Chaudhari

This study was undertaken during the winter season on healthy mature Gir cattle and Murrah buffalo bulls (n=3 each). The semen samples (6 ejaculates/bull, total 36 ejaculates) collected in the morning using artificial vagina were evaluated for routine seminal attributes, including acrosomal and plasma membrane integrity. The samples were then diluted @ 100 million sperm/ml with tris fructose yolk glycerol extender without and with sericin @ 0.1, 0.25, 0.5 and 1.0% (w/v), filled in French mini-straws, and frozen in LN2 using biofreezer as per standard freezing protocol. Straws were thawed in water bath at 37°C for 30 sec and evaluated for post-thaw quality, viz., motility, viability, morphology, acrosome integrity and plasma membrane integrity (HOST). Lipid peroxidation (malondialdehyde - MDA production) and activities of enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx) were assessed as oxidative markers in seminal plasma of freshly diluted and frozen-thawed semen samples. Sericn at 0.5% level significantly (p less than 0.01) improved the post-thaw sperm quality with reduced oxidative stress in both the species. The breed-wise correlation coefficients (r) among sperm quality attributes and oxidative markers were studied in fresh and frozen-thawed semen of each species, and also for fresh with frozen-thawed semen. The findings revealed significant interrelationships amongst most of the attributes of fresh as well as post-thawed semen and also of fresh semen attributes with those of cryopreserved semen including oxidative markers in both the species. Sperm motility estimation in fresh, pre-freeze and post-thawed semen was a legitimately good indicator of quality of spermatozoa at various steps of semen processing/freezing, and its fertilizing potential. Thus, the sperm motility, HOS test and either MDA or SOD/GPx activity alone may be used as valuable and practical tools for routine assessment of bovine semen quality considering significant correlations found between them.


Author(s):  
Rosileia Silva SOUZA ◽  
Larissa Pires BARBOSA ◽  
Cristiane Silva AGUIAR ◽  
Renan Luiz Albuquerque VIEIRA ◽  
Márcio Oliveira RIBEIRO ◽  
...  

ABSTRACT The objective of this study was to evaluate the effects of the inclusion of flaxseed in the diet of male goats on the resistance of semen to the cryopreservation process. Sixteen males were distributed in four groups and fed a diet supplemented with 0, 4, 8, and 12% of flaxseed for a period of 60 days. Only the ejaculates that presented motility and vigor above 70% and 3, respectively, were sent through the cryopreservation process. After thawing, the semen was evaluated through thermo resistance, hypoosmotic, and acrossomal integrity tests. The data were submitted to analysis of variance and regression at 5% of significance. There was positive quadratic behavior for motility after 60, 120, and 180 min in the thermoresistance test (TTR), and positive quadratic behavior for sperm vigor after thawing after 120 and 180 min in the TTR (P < 0.05). However, negative quadratic behavior was obtained for plasma membrane integrity according to the hypoosmotic test (P < 0.05) and there was a difference in the acrosomal integrity test, presenting an optimum maximum level of 3.25% of flaxseed for acrosomal integrity of 65.83% (P < 0.05). The results obtained demonstrated that the addition of as much as 12% of flaxseed to the diet of goat breeders improved post-thawing sperm quality.


Animals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 999 ◽  
Author(s):  
Ayman Abdel-Aziz Swelum ◽  
Islam M. Saadeldin ◽  
Hani Ba-Awadh ◽  
Mohsen G. Al-Mutary ◽  
Abdullah F. Moumen ◽  
...  

This study compared the efficiency of commercial egg yolk-free (AndroMed, OPTIXcell) and egg yolk-supplemented (Triladyl, Steridyl) Tris-based extenders for semen cryopreservation in seven adult dromedary camels. The camel-specific extender SHOTOR was used as control. The collected semen samples were evaluated and diluted with SHOTOR, Triladyl, Steridyl, AndroMed, or OPTIXcell. The diluted semen was gradually cooled and equilibrated for two hours before liquid nitrogen freezing. Semen was evaluated prior to freezing and after freeze-thawing cycles for motility, kinetics, vitality, abnormality, plasma membrane integrity, and DNA fragmentation using computer-assisted sperm analysis. In pre-freezing evaluation, progressive sperm motility was higher in SHOTOR-diluted samples (21.54 ± 1.83) than in samples diluted with Steridyl, OPTIXcell, or AndroMed (15.76 ± 1.80, 17.43 ± 1.10, and 13.27 ± 1.07, respectively). Moreover, Triladyl and SHOTOR resulted in significantly (p < 0.05) better sperm vitality and DNA integrity than all other diluents, but Triladyl resulted in a significantly (p < 0.05) better plasma membrane integrity (87.77 ± 0.31) than SHOTOR (85.48 ± 0.58). In the post-thawing evaluation, Triladyl led to significantly (p < 0.05) higher sperm motility (38.63 ± 0.81%; p < 0.05) when compared to SHOTOR, Steridyl or AndroMed (35.09 ± 1.341%, 34.4 ± 0.84%, and 31.99 ± 1.48%, respectively), with OPTIXcell being the least efficient (28.39 ± 0.86%). Progressive sperm motility was the highest when using Triladyl. Post-thawing curvilinear, straight line and average path sperm velocities were highest with Triladyl and lowest with AndroMed. Triladyl led to the highest linearity coefficient and straightness sperm coefficient, while SHOTOR to the highest DNA and plasma membrane integrity. OPTIXcell and AndroMed resulted in poor post-thawing sperm vitality, while Steridyl was less efficient than Triladyl. The highest rate of sperm abnormalities was recorded with OPTIXcell and the lowest with SHOTOR or Triladyl. In conclusion, SHOTOR, Triladyl, Steridyl, AndroMed, and OPTIXcell can all be used for camel semen cryopreservation; however, SHOTOR and Triladyl provided the best post-thawing sperm quality. Based on our findings, Triladyl is the best commercially available extender for dromedary camel semen cryopreservation to date.


2015 ◽  
Vol 27 (1) ◽  
pp. 127
Author(s):  
C. P. Freitas-Dell'aqua ◽  
C. Ramires Neto ◽  
Y. F. R. Sancler-Silva ◽  
P. M. Papa ◽  
J. A. Dell'aqua ◽  
...  

Commercial freeze extenders have different composition and ratio of cryoprotectors; freezing and thawing protocols are different for each extender. The aim of this experiment was to observe the effect of thawing curve in stallion frozen semen with 2 commercial extenders. Two ejaculates from each of 9 stallions of different breeds (Quarter Horses and Mangalarga Marchador) were used. Semen was collected using an artificial vagina, and the ejaculate was divided into 2 groups following the manufacture's protocol: group 1 (INRA), in which the semen was diluted 1 : 1 with the extender INRA 96TM (IMV, Paillette Crista, France) and group 2 (BC), in which the semen was diluted (1 : 1) with the extender Botu-SemenTM (Botupharma, Brazil). The samples of the 2 groups were centrifuged at 600 × g for 10 min, the supernatant was discarded, and the pellet was resuspended with INRA FreezeTM (group INRA, IMV) and with BotucrioTM (group BC, Botupharma) at the concentration of sperm 100 × 106 sperm mL–1. After this, the semen was packaged in 0.5-mL straws. For each group the freezing process was carried out according to the manufacturer's instructions. The straws were thawed in a water bath with 3 different thawing curves: 37°C for 30 s (37/30), 46°C for 20 s (46/20), and 75°C for 7 s (75/7) before analysis. The aim of these rates is to keep the semen in 37°C post-thaw. The sperm kinetic analysis was performed by computerized method (CASA, HTM-IVOS, IMV, USA) and the analysis of plasma membrane integrity by flow cytometer (BD LSR Fortessa, Becton Dickinson, Mountain View, CA, USA). Data of sperm kinetic and of plasma membrane integrity were compared among the 3 thawing curves for one extender using analysis of variance. Differences were considered significant at a probability level of 5%. No differences were observed in total motility (%, BC 37/30 = 72.8 ± 14.4; BC 46/20 = 70.0 ± 14.2; BC 75/7 = 70.3 ± 12.0 v. INRA 37/30 = 57.2 ± 19.1; INRA 46/20 = 50.0 ± 21.9; BC 75/7 = 58.8 ± 20.8), progressive motility (%, BC 37/30 = 36.9 ± 8.2; BC 46/20 = 34.4 ± 10.5; BC 75/7 = 33.6 ± 7.8 v. INRA 37/30 = 25.3 ± 12.7; INRA 46/20 = 21.9 ± 13.9; BC 75/7 = 28.9 ± 14.8), rapid sperm (%, BC 37/30 = 59.7 ± 16.4; BC 46/20 = 56.8 ± 17.1; BC 75/7 = 58.1 ± 14.9 v. INRA 37/30 = 38.3 ± 20.9; INRA 46/20 = 35.3 ± 22.9; BC 75/7 = 44.4 ± 23.8), and plasma membrane integrity (%, BC 37/30 = 49.1 ± 14.8; BC 46/20 = 43.1 ± 13.1; BC 75/7 = 46.7 ± 11.8 v. INRA 37/30 = 32.2 ± 10.7; INRA 46/20 = 29.6 ± 10.1; BC 75/7 = 37.4 ± 9.1) among the 3 thawing curves for INRA and BC groups. In this study, we can conclude there is no influence of the 3 tested thawing curves in sperm quality for stallion frozen semen with INRA Freeze and Botucrio extenders.


2015 ◽  
Vol 27 (1) ◽  
pp. 118
Author(s):  
H. Vaseghi-Dodaran ◽  
M. Zhandi ◽  
M. Sharafi ◽  
E. Nejati-Amiri ◽  
A. Nejati-Javaremi ◽  
...  

A variety of controlled mild stressors have been applied for activation of temporary response in oocytes, embryos, and somatic cells. So far, several stressors have been used to induce mild stress, including that of hydrostatic pressure, osmotic stress, mechanical stress, and oxidative challenges. Based on these evidences, we hypothesised that the ethanol in sublethal concentration would be capable of generating mild stress that may ultimately leads to an adaptive response in spermatozoa. To evaluate this hypothesis, semen samples (n = 24, 6 ejaculates/bull) from 4 Holstein bulls were collected and pooled for each replicate. Pooled samples were divided into 5 equal parts and each part diluted with tris-glycerol-based (Optidyl®) extender containing 0 (O-E0), 0.03 (O-E3), 0.09 (O-E9), and 0.15 (O-E15) % (vol/vol) ethanol and frozen. After thawing, sperm motility and velocity parameters (sperm class analysis), apoptosis status (Phospatidylserin Translocation Detection commercial kit), plasma membrane integrity (eosin-Nigrosin staining), malondialdehyde concentration (thiobarbituric acid reaction), and mitochondrial activity (rhodamine-123 and propidium iodide) were evaluated. The data were analysed using Proc Mixed of SAS 9.1 (version 9.1; SAS Institute Inc., 2002, Cary, NC, USA). Tukey's test was used to compare least squares means. As a result, the O-E9 group showed higher (85.2%) percentage of total motility compared with O-E0 (73.6%), O-E3 (51.9%), and O-E15 (67.5%) groups (P < 0.05). A highest (P < 0.05) percentage of live spermatozoa were observed in the O-E9 (62.9%) group as compared with O-E0 (49.4%), O-E3 (50.3%), and O-E15 (49.6%) groups, and also the proportion of apoptotic spermatozoa in the O-E9 (10.6%) group tended to be lowest as compared with those of O-E0 (15.6%), O-E3 (17.2%), O-E15 (14.1%) groups (P > 0.05). The plasma membrane integrity was higher (P < 0.05) in O-E9 (90.8%) compared with O-E3 (75%) and O-E15 (77.2%) groups; however, the difference was not significant when the O-E9 group was compared with the O-E0 group (83.2%; P > 0.05). Obtained results revealed that malondialdehyde level was lower in O-E3 (1.03%), O-E9 (0.63%), and O-E15 (0.89%) groups compared with the O-E0 (1.94%) group (P < 0.05). Furthermore, the percentage of live spermatozoa with active mitochondria was higher in O-E9 (57.7%) and O-E15 (57.5%) groups compared with O-E0 (49.1%) and O-E3 (38.2%) groups (P < 0.05). These results strongly suggest that supplementation of Optidyl® extender with sublethal concentration of ethanol influences post-thawed bull sperm quality in a dose-dependent manner. However, further studies are needed to empirically determine the effect of supplementation on fertilization and pregnancy outcome.


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