41 THE EFFECT OF AMBIENT TEMPERATURE ON SPERM MOTILITY DURING LIQUID STORAGE OF VENDA COCK SEMEN AND INDIVIDUAL DIFFERENCES IN SPERM CRYOTOLERANCE

2012 ◽  
Vol 24 (1) ◽  
pp. 133
Author(s):  
M. L. Mphaphathi ◽  
D. Luseba ◽  
M. B. Masenya ◽  
B. Sutherland ◽  
T. L. Nedambale

Improving techniques for liquid storage of cock semen can increase the efficiency of AI programs in the poultry industry. The aims of the present study were (1) to compare storage of cock sperm for 24 h at 5 and 25°C and (2) to test the cryotolerance of sperm cell motility in individual Venda cocks. Semen was collected with the abdominal massage method, from 6 indigenous Venda cocks. Cocks were 26 weeks of age and were kept under the same conditions. After macroscopic analysis, semen was pooled and diluted (1:2) with Kobidil+ extender and divided into 3 equal parts. Part 1 was evaluated immediately (0 h), part 2 was stored at 5°C and part 3 was stored at 25°C and evaluated for sperm motility and velocity parameters at 4, 8, 12 and 24 h of storage. For cryopreservation, semen was diluted (1:2) with modified Kobidil+ extender supplemented with 8% of dimethyl sulfoxide. Individual ejaculates were equilibrated at 5°C for 4 h and then loaded into the programmable freezer. Then, semen straws were thawed at 5°C. Sperm motility and velocity parameters were evaluated using the Sperm Class Analyzer® system. Six replicates were done per trial. Data were analysed using the statistical programme GenStat®. Treatment means were separated using Fisher's protected t-test least significant difference (P < 0.05). Total sperm cell motility rate was 87.5% and decreased significantly during in vitro storage and was <31% after 24 h at 25°C. Semen samples stored at 5°C showed a total sperm cell motility rate of above 50% after 24 h. There was a slight linear decrease in the percentage of sperm with progressive motility and rapid velocity as the storage period increased, irrespective of the storage temperature. The rapid and medium motility percentages were higher in fresh semen and significantly decreased (P < 0.05) during the incubation period. There was variation in the total sperm cell motility of fresh and frozen semen among cocks. There was no significant difference in variation in non-progressive and medium percentage (P > 0.05) motility in diluted fresh or frozen sperm cells or in the percentage of sperm with rapid motility in thawed semen. There was variation in <25% of the cocks in total sperm motility rate. In summary, cryopreservation reduced sperm cell motility and velocity rates in all the cock semen donors. We found that cryotolerance of cock sperm does vary among males. Furthermore, the lower temperature 5°C was suitable for semen storage of Venda cocks. This temperature (5°C) could potentially improve methods of semen equilibration before cryopreservation. The study was supported by an Agricultural Research Council Parliamentary Grant, Department of Agriculture Forestry and Fisheries and National Research Foundation-GUN No RT21 and 24000 (NRF). The Germplasm Conservation & Reproduction Biotechnologies (GCRB) group is thanked for their support.

2013 ◽  
Vol 25 (1) ◽  
pp. 185
Author(s):  
M. M. Seshoka ◽  
M. L. Mphaphathi ◽  
F. V. Ramukhithi ◽  
T. R. Netshirovha ◽  
C. Hlungwani ◽  
...  

There are bull shortages in South African poor rural areas. Artificial-insemination technology could play a significant role on breeding emerging farmer’s cattle. The objective of this study was to compare glycerol concentrations (0, 4, 8, or 12%) during freezing of Nguni bull semen to conduct AI in different villages. Semen was collected by electro ejaculator from 2 Nguni bulls of known and proven fertility. Collected semen samples were kept in a thermo flask (37°C) and transported to the laboratories within 10 min after collections. Semen samples were pooled and evaluated by Sperm Class Analyser® and allocated randomly per treatment. Semen was then diluted (1 : 2 v:v) with egg-yolk citrate extender supplemented with either 0% (negative control), 4, 8, and 12% of glycerol concentration or AndroMed® (positive control). Semen samples were equilibrated for 4 h at 5°C. After equilibration period, samples were loaded into 0.5-mL straws and placed horizontally into the controlled rate (–5, –8, –10, –12, –15, –25, –35°C min–1) from 5°C until target temperature of –80°C is reached. The frozen semen straws were stored in a liquid nitrogen tank (–196°C) until thawing. Treatment means were separated using Fisher’s protected t-test least, and data are presented as mean ± SD. There was a significant differences (P < 0.05) between raw total sperm motility (83.3 ± 19.3) and frozen–thawed sperm with either 0% (0.0 ± 0.0), 4% (30.2 ± 13.4), 8% (47.9 ± 12.5), or 12% (61.5 ± 4.7) of glycerol and on AndroMed® (27.7 ± 17.8) group. Regardless of the glycerol concentrations used, the freezing-thawing process reduced (P < 0.05) the Nguni total sperm motility rate compared to uncryopreserved sperm (83.3 ± 19.3). In conclusion, egg-yolk citrate extender supplemented with 12% glycerol yielded a better (P < 0.05) total sperm motility rate (61.5 ± 4.7) as compared with the 0% (0.0 ± 0.0), 4% (30.2 ± 13.4), 8% (47.9 ± 12.5), and AndroMed® (27.7 ± 17.8) group. Further studies are required to test other levels of glycerol concentrations (>12%) on freezing Nguni semen and conducting AI.


2015 ◽  
Vol 27 (1) ◽  
pp. 126
Author(s):  
H. S. Martins ◽  
M. F. Brito ◽  
I. B. M. Sampaio ◽  
R. Stahlberg ◽  
M. R. Souza ◽  
...  

During cryopreservation, the sperm were submitted to an increased generation of reactive oxygen species. Furthermore, because of the large portion of seminal plasma removal, there is a decrease of sperm antioxidant protection. Addition of antioxidants proteins found in seminal plasma, such as lactoferrin (Lf) and catalase (Cat), to the freezing semen extenders could protect the sperm during cryopreservation. Lactoferrin is a transferrin, which prevents the hydroxyl radicals generation, and Cat plays an antioxidant role. The aim of this study was to determine the effects of Lf and Cat supplementation to the INRA 82 freezing extender (Battelier et al. 1997) on sperm motility parameters and membrane functionality of stallion frozen semen. Semen from 6 stallions was collected with an artificial vagina, diluted with Kenney extender (1 : 1), and centrifuged (500 × g, 10 min). The supernatant was discarded, and sperm number per milliliter was calculated. Semen was resuspended with 3 extenders to 100 × 106 sperm mL–1. The treatments were distributed in (F1) control, INRA 82 freezing extender (Battelier et al. 1997), (F2) F1+ 500 μg mL–1 lactoferrin, and F3) F1 + 200 IU mL–1 catalase. Semen samples were packaged in 0.5-mL straws and cooled to 5°C (0.27°C min–1). For semen freezing, the straws were laid over the LN vapor for 20 min and plunged into the LN. The straws were thawed at 37°C for 30 s. Motility parameters of frozen semen were determined using a computer sperm cell analysis, and sperm membrane functionality was assessed by the hyposmotic swelling test (Lagares et al. 1998). The data were analysed using Friedman test using stallion as a block. A probability of P < 0.05 was considered significant. There was no significant difference between the percentage of total sperm motility (median, minimum-maximum value; F1: 29.9, 11.0–82.7; F2: 49.8, 7.7–55.2; F3: 39.8, 5.7–92) and progressive sperm motility (F1: 7.1, 3.2–23.3; F2: 13.4, 2.6-22.4; F3: 15.6, 1.1–29.6), and functional sperm membrane (F1: 26.7, 14.7–56.2; F2: 50.5, 15.7–61.7; F3: 46.6, 13.8–50.9) with regard to the treatment. However, the velocity parameters: velocity average path (F1: 29.3, 22.1–33.80; F2: 34.6, 24.8–44; F3: 35.7, 18.2–42.6), velocity curvilinear (F1: 36.9, 30.5–45.1; F2: 42.5, 34.7–51; F3: 44.6, 25.5–50.9), and velocity straight line (F1: 23.4, 17–3.60; F2: 28.9, 18.8–38.2; F3: 26.6, 13.6–37.2) in the treatment with Lf (F2) were higher compared with the control (F1; P < 0.05). These results corroborate with studies reporting the lack of positive effect on equine sperm motility when antioxidants were added to skim milk-based extenders. Although the addition of Lf or Cat to skim milk-based extenders did not improve the motility sperm characteristics and sperm membrane functionality, more studies about the positive effect of Lf on the velocity parameters are necessary. Lactoferrin could then play an important role on the oxidative metabolism, which provides energy to the sperm movement.Acknowledgments to the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Brazil, for the financial support.


2017 ◽  
Vol 29 (1) ◽  
pp. 190
Author(s):  
A. M. Raseona ◽  
O. A. Ajao ◽  
L. D. Nethengwe ◽  
L. R. Madzhie ◽  
T. L. Nedambale ◽  
...  

Preservation of semen is an important process to ensure that semen quality is sufficient for assisted reproductive technologies. The aim of this study was to evaluate the viability of bull semen collected by electro-ejaculation using commercial semen extender and 2 modified culture media stored at controlled RT (24°C) for 72 h. Two Nguni bulls were used for semen collection; after collection, the semen was evaluated macroscopically for volume, pH, and colour, and microscopically for sperm motility, viability, and morphology. Uncontaminated semen samples with progressive motility >70% and morphological defects <20% were pooled after collection before being aliquoted into 3 extenders, namely Triladyl, modified Ham’s F10, and TCM-199 culture media, at a dilution ratio of 1:4 and then stored at controlled RT (24°C). Sperm motility rate was analysed using the computer-aided sperm analyser after 0, 24, 48, and 72 h of storage. Sperm morphology and viability was performed after staining the sperm cells with spermac and nigrosine-eosin stain, respectively. The study was replicated 4 times and data were analysed using ANOVA. Triladyl had a higher sperm viability rate (41.3%) and total motility rate (96.3%) for 72 h (P < 0.01) compared with the 2 modified culture media, Ham’s F10 (26.5 and 86.8%) and TCM-199 (25.0 and 86.7%), respectively. However, Ham’s F10 had higher progressive motility rate (37.8%) as compared with the other extenders, TCM-199 (31.7%) and Triladyl (23.4). There was no significant difference (P > 0.05), in viability rate between Ham’s F10 (26.5%) and TCM-199 (25.0%). No significant difference (P > 0.05) in straight line velocity was observed for the three extenders. Furthermore, no significant difference was observed in total sperm abnormalities, except for reacted acrosomes and absent tails (P > 0.05), between the 2 Nguni bulls. Nguni semen can be preserved in Triladyl or modified Ham’s F10 and TCM-199 culture media stored at 24°C and stay viable for 72 h. Triladyl proved to be the best suitable extender of the 3 extenders, showing higher sperm viability and total motility rate as compared with Ham’s F10 and TCM-199 modified culture media.


2020 ◽  
Vol 32 (2) ◽  
pp. 187
Author(s):  
M. Felix ◽  
I. Ortiz ◽  
H. Resende ◽  
J. Brom-de-Luna ◽  
C. Love ◽  
...  

Equine semen used for intracytoplasmic sperm injection (ICSI) is typically frozen-thawed and may be of poor quality. To prepare sperm for ICSI, semen is typically centrifuged to remove freezing extender. However, centrifugation can cause damage to sperm, which is especially meaningful if sperm quality is already poor. We evaluated a method for selection of sperm without centrifugation, using a “swim-over” technique, and assessed the effect of pentoxifylline, a phosphodiesterase inhibitor that increases sperm motility in other species. To mimic poor-quality semen, we thawed frozen semen (1×) and re-froze it three additional times (4×). Aliquots (0.25 µL; 50,000 sperm) of 1× or 4× semen were placed at the bottom of the right leg of an “H,” made using 15µL of medium by tracing a template placed below a Petri dish. The medium used (Hanks’ balanced salt solution with 40mg mL BSA and added lactate and pyruvate) contained different concentrations of pentoxifylline (0, 0.5, 1, 2 or 4mgmL−1). One µL of medium was removed from the tip of the left arm of the H after 15 and 30min incubation, and the number of sperm were counted. In a second study, we evaluated the effect of pentoxifylline on sperm motility parameters using computer-assisted sperm motility analysis. After thawing, 1× and 4× semen was washed to remove freezing extender and resuspended in the same medium but with 7mgmL−1 bovine serum albumin (BSA), containing the different pentoxifylline concentrations. In Study 1, the number of collected sperm did not differ significantly for 1× sperm exposed to 0 to 4mgmL−1 pentoxifylline (means of 15 to 23 sperm at 15min, and 18 to 25 sperm at 30min). Similarly, in 4× frozen semen, there was no significant difference in number of collected sperm between 0mgmL−1 and 2 or 4mgmL−1 pentoxifylline concentrations (&lt;1 to 6 at 15 min; 5 to 6 at 30min). In Study 2, at 0min,% total motility was significantly higher in 1 and 2mgmL−1 pentoxifylline than in 0mgmL−1 for 1× sperm (47.8±1.7 and 49.3±1.9, vs. 32.1±3.9, respectively; P=0.018) and significantly higher for 1, 2, and 4mgmL−1 pentoxifylline than for 0mgmL−1 for 4× sperm (3.9±0.9, 5.7±0.4, and 8.2±0.5, vs. 1.2±0.4; P=0.0001). Similar results were found at 15 and 30min for 1×, and at 15min for 4×. Pentoxifylline at 1 to 4mgmL−1 significantly increased the percentage of progressive motility in 1× sperm at 30min (17.8±1.3, 21.8±2.7, and 20.3±1.2, vs. 10.0±0.4; P=0.002) and, at 4mgmL−1, increased the percentage of progressive motility in 4× sperm at 0min (1.43±0.1 vs. 0.2±0.1; P=0.005) and 15min (1.4±0.2 vs. 0.1±0.0; P=0.0001). Exposure of poor-quality semen to pentoxifylline at 4mgmL−1 improved total and progressive motility but did not increase the recovery of motile sperm in a swim-over collection preparation.


2018 ◽  
Vol 4 (1) ◽  
pp. 55-62 ◽  
Author(s):  
Md Abdullah Al Mansur ◽  
Md Golam Shahi Alam ◽  
Pankaj Kumar Jha ◽  
Md Asaduzzaman Rimon ◽  
Nazmun Naher ◽  
...  

This study was undertaken to study the AI conception rate using frozen semen at field level. Five farms in Mymensingh, Bangladesh were selected for AI Trial in field ewes. Four rams were selected for semen collection, evaluation, and frozen semen production and further to study conception rate followed by intra-cervical AI in both natural and synchronized ewes. Conception rate were confirmed by non-returned rate and ultrasound scanning at 30-40 days of post insemination. The volume, colour, mass activity, sperm motility, viability, concentration, HOST +ve (%) and normal spermatozoa percentages were 0.8±0.3 ml, 3.9±0.3, 4.4±0.6, 81.3±5.0%, 90.0±4.0%, 3519.0±545.6x106/ml, 87.4±3.3% and 85.6±1.8%, respectively. The sperm concentration of ram R#6 was significantly higher (P<0.05) (4120.5±93.5x106/ml) compared with other rams. The mean motility and viability of pre-dilution, 120 minutes of addition of Part-A, 240 minutes of addition of Part-B and post-thaw were (83.8±4.8%, 81.3±2.5%, 80.0±4.1% and 41.3±9.5%) and (93.3±1.0%, 90.0±1.4%, 88.8±1.0% and 58.3±8.7%), respectively. There were no significant difference (P˃0.05) between pre-dilution and post-dilution sperm motility and viability percentage however, post-thaw sperm motility and viability significantly (P<0.05) decreased compare with the motility and viability of pre-dilution and post-dilution values. Motility and viability percentages of frozen semen did not decrease significantly (P> 0.05) with the increase of preservation time. The mean motility and viability at 24 hrs, day 7, day 15 and day 30 were 41.3±9.5%, 41.5±8.5%, 41.8±9.9% and 40.5±10.2%; and 59.0±10.1%, 58.5±7.7%, 59.0±8.8% and 57.8±8.3%, respectively. The conception rates in natural and synchronized estrous were 26.7% and 25%, respectively. There was no significant difference in conception rates between the natural and synchronized oestrous in field level. However, the present non-return rate and conception rate indicate the suitability of produced frozen semen application in the field level.Asian J. Med. Biol. Res. March 2018, 4(1): 55-62


2014 ◽  
Vol 26 (1) ◽  
pp. 140
Author(s):  
M. M. Seshoka ◽  
M. L. Mphaphathi ◽  
T. L. Nedambale

Cryopreservation has been reported to damage approximately 40 to 50% of viable spermatozoa in bulls. It is critical to evaluate frozen-thawed spermatozoa with computer-aided sperm analysis (CASA) and find a suitable cryoprotectant for Nguni semen. The study was conducted to compare cryo-effectiveness of glycerol (GLY), dimethyl sulfoxide (DMSO), propanediol (PND), and ethylene glycol (EG) cryoprotectants at 12% concentrations during freezing of Nguni bull semen. Semen was collected from 18 stud Nguni bulls of proven fertility with the use of an electro-ejaculator. Collected semen samples were kept in a thermo flask (37°C) and transported to the laboratories. Semen samples were pooled and sperm motility rate was evaluated using CASA. Semen was then diluted (1 : 2; vol : vol) with egg-yolk citrate extender supplemented with either 12% GLY, DMSO, PND, or EG. Semen samples were equilibrated for 4 h at 5°C. After equilibration, samples were loaded into 0.25-mL straws and placed into the controlled rate programmable freezer using a customized freezing curve (from 5 to –5°C at 0.008°C min–1 and from –3 to – 130°C at 6°C min–1). Following thawing of semen, artificial insemination was conducted on 104 oestrus-synchronised Nguni cows. The IVF was also conducted on 120 oocytes to check the cleavage rate. Data were analysed using ANOVA. There was a significant difference (P < 0.05) between raw total sperm motility (94.70 ± 2.63) and frozen-thawed sperm total motility with GLY (77.80 ± 11.03), EG (20.35 ± 11.86), DMSO (15.68 ± 10.14), and PND (11.19 ± 11.27) groups. The pregnancy rate following artificial insemination was 75.9% and a total of 86.6% oocytes had cleaved after fertilization with frozen (12% GLY)/thawed semen. In conclusion, cryopreservation process reduced sperm motility and velocity rates, regardless of cryoprotectant. Egg-yolk citrate extender supplemented with 12% glycerol had recorded the highest post-thaw sperm motility rate.


2016 ◽  
Vol 28 (2) ◽  
pp. 149
Author(s):  
M. M. Seshoka ◽  
M. L. Mphaphathi ◽  
K. S. Mafolo ◽  
M. Nkadimeng ◽  
Z. C. Raphalalani ◽  
...  

Traditionally, commercial hen egg yolk has been used in extenders or freezing media because of its easy availability. However, the use of quail egg yolk has not been used for preserving Nguni bull semen. The aim of the study was to compare the suitability of different quail egg yolk concentrations (5, 10, 15, and 20%) for cryopreserving Nguni bull semen. Semen was collected from 14 stud Nguni bulls with the aid of electro ejaculator. Collected semen samples were kept in a thermos-flask containing warm water at a temperature of 37°C and transported to the laboratory for further analyses. The sperm motility traits were evaluated using computer-aided sperm analysis prior extension. Semen samples were then randomly allocated into 5, 10, 15, and 20% of quail egg yolk and 20% concentration of chicken egg yolk (control) in citrate extender. The extender was supplemented with 12% of glycerol (Seshoka et al. 2012) as a cryoprotectant, and semen samples were diluted (1 : 2) and equilibrated for a period of 4 h at 5°C. After equilibration, semen samples were loaded into 0.25-mL straws, placed into a controlled rate programmable freezer, and stored in a LN tank (–196°C) until thawing. Frozen semen straws were thawed in a water bath at 37°C for 1 min. Thawed semen was evaluated for sperm motility traits using a computer-aided sperm analysis system. Data were analysed with ANOVA. A significant difference was recorded between fresh total sperm motility rate (99%) and frozen-thawed semen samples with either 5% (87.3%) quail or 20% (87.6%) chicken egg yolk citrate extender compared with 10% (92.6%), 15% (91.2%), or 20% (89.9%) quail egg yolk citrate extender. Moreover, fresh semen also resulted in a significantly higher progressive sperm motility rate (39.3%) as compared with frozen-thawed with 5% (26.2%) or 20% quail (28.5%) or 20% chicken (22.7%) egg yolk citrate extender. The results also demonstrated that the use of 10, 15, and 20% quail egg yolk in citrate extender yielded comparable results on total sperm motility with fresh semen as compared with 5% quail and 20% chicken egg yolk. In conclusion, quail egg yolk extender provided sufficient cryo-effectiveness to cryopreservation of Nguni bull semen.


Author(s):  
E. Somogyi ◽  
J. Lázár ◽  
P. Bodor ◽  
T. Kaszab

AbstractColour is one of the most important phenotypic characters of the table grape cultivars, which has high importance in the consumer's preference. This morphological trait is variable and not consistently uniform within a cultivar or even a bunch. Between harvest and consumption fruits are stored for several weeks which time is influencing the colour of the berry. In this study 10 grapevine accessions (Agaphante, KM98, Korai piros veltelini, Korona, Pinot gris, Pozsonyi, Ros de Minis, Tramini piros, T9, Zenit) were collected from the germplasm collection of the Research Institute for Viticulture and Oenology of the National Agricultural Research and Innovation Centre of Kecskemét. The samples were investigated by ColorLite Sph850 spectrophotometer. The colour of 30 berries per accessions were measured in 3 replicates per berry. The aim of this study was to evaluate the colour and the effect of cold storage. L✻, a✻, b✻ values of each accessions were evaluated after the sampling and until a visible reduction in the quality of the grapes, at most 4 weeks with 1-week intervals from the harvest. Results showed that there is a significant difference among the cultivars in the L∗, a∗, b∗ values. The length of cold storage also has a significant effect on the colour of the accessions as the values are changing in some cases of the 1-week storage period.


2020 ◽  
Vol 50 (3) ◽  
pp. 389-396
Author(s):  
K.S. Mafolo ◽  
C.M. Pilane ◽  
T. Chitura ◽  
T.L. Nedambale

Traditionally, egg yolk is a protective agent that is used to freeze semen in various species. However, the addition of egg yolk in extender risks the introduction of disease. Therefore, an alternative cryoprotective agent should be found to preserve ram semen. The aim of this study was to evaluate the effect of phosphatidylcholine (PC) as a protective agent in extender with or without egg yolk on semen characteristics and acrosome integrity of frozen then thawed Bapedi ram semen. Semen was collected from four mature Bapedi rams, in the Agricultural Research Council (ARC) Germplasm Conservation Programme, using an artificial vagina. Following collection, semen samples were randomly diluted into Tris-based extender (1: 2), with and without egg yolk, and supplemented with four concentrations of PC liposome (0 mg/ml), 0.25 mg/ml, 0.5 mg/ml and 0.75 mg/ml). Supplementation of PC liposome in extender with or without egg yolk did not improve the semen total motility (TM), progressive motility (PM) and rapid motility (RM) rate. The sperm cell membrane integrity in extender with or without egg yolk was not influenced by the supplementation of PC liposome after thawing (P >0.05). The addition of PC liposome to Tris-based extender with egg yolk had a similar result to control (Tris-based extender with egg yolk) on sperm cell acrosome integrity. In conclusion, supplementation of PC liposome to Tris-based extender without egg yolk had lower sperm cell viability and motility rates compared with the extender with egg yolk, regardless of concentration.Keywords: acrosome, cryoprotectant, liposome, membrane, motility


2008 ◽  
Vol 20 (1) ◽  
pp. 119
Author(s):  
A. Garcia Guerra ◽  
M. P. Etcheverry ◽  
D. Rodriguez ◽  
G. Larraburu ◽  
G. M. Brogliatti

One of the key factors for successful long-term cryopreservation in liquid nitrogen is maintaining the samples at –130°C or lower at all times to avoid cell damage (Barth 1991 Proc. 10th Ann. Conv. Am. Embr. Transf. Assoc., 20–26). Previous data indicated that exposure of the semen straw to ambient temperature for more than 15 s can raise the temperature above –130°C and reduce sperm motility, as determined by subjective evaluation (Berndtson et al. 1976 Proc. 6th NAAB Tech. Conf. Artif. Insem. Reprod., 51–60). The computer-assisted semen analysis (CASA) system provides an opportunity to assess multiple motility characteristics on a semen sample objectively and with high repeatability. An experiment was designed to evaluate the effect of exposing frozen semen in 0.5-mL straws to room temperature for 15, 30, 60, or 120 s on motility characteristics assessed by CASA system. Twenty-eight ejaculates from different bulls (19 Angus, 7 Hereford, 1 Brangus, 1 Shorthorn) were diluted using a chemically semi-defined media (Andromed, Minitüb, Tiefenbach, Germany) and frozen in an automatic freezer (Digicool, IMV, Paillette Crista, France). Five frozen straws per bull were used, one for each time of exposure and one as control (0 s = 0 time). Straws were exposed to room temperature (15°C ± 0.78) for different times and then placed back into liquid nitrogen. Semen thawing was conducted in a water bath at 37°C for 1 min. Motility characteristics were evaluated by the IVOS SpermAnalyzer (Hamilton Thorne Research, Beverly, MA, USA). Two chambers of 20-μm depth and 5 fields per chamber were analyzed (30 frames/0.5 s for each field). Seven motility parameters were evaluated: motile sperm (%), progressive sperm (%), VAP (path velocity, μm s–1), VCL (track speed, μm s–1), ALH (lateral amplitude, μm), BCF (beat frequency, Hz), and LIN (Linearity, %). The Kruskal–Wallis test was used to compare variables among groups, and results are shown in Table 1. There is a significant difference (P < 0.05) in the % of motile and progressive sperm when time of exposure was increased. There was a drastic and significant reduction in the percentage of motile and progressive sperm when exposure to 15°C was longer than 30 s. The live cells had similar motile characteristics: VAP, VCL, ALH, BCF, and LIN. In conclusion, sperm motility would be affected if straws are exposed for more than 30 s. More research should be done to test higher room temperatures, detect viability effects, and determine pregnancy rates after AI. Table 1. CASA of frozen sperm motility characteristics at different times of exposure at 15°C This research was supported by Centro Genetico Bovino Eolia S.A.


Sign in / Sign up

Export Citation Format

Share Document