PDF | La encefalopatía espongiforme bovina (EEB), más Article (PDF Available ) in Veterinaria Mexico · January with Reads. México, 13 Mar. Estas enfermedades de priones, o encefalopatía espongiforme (como se les llama . Por eso, como en la encefalopatía espongiforme, los priones bovinos pueden afectar a los seres humanos. No existe la. del análisis efectuado: Cuantitativo. Temática: “Análisis de riesgo sobre la ocurrencia de la encefalopatía espongiforme bovina en México”. INTRODUCTION.
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Post-thaw acrosomal viability and reaction in sperm obtained from equine epididymis tail. Soto IIJ. Verona IIR. Epididymis was dissected to perform the retrograde flushing of the epididymis tailusing 10 mL of a diluent based on skim milk INRA The diluent obtained with the spermatic content was recovered in graduated collecting tubes and 1mL of each sample was taken to be evaluated.
The evaluations were on: Subsequently, samples were packed into 0.
Posteriormente las muestras se envasaron en pajillas de 0. Studies have shown that sperm retrieved from epididymis is highly efficient, and even when it is kept at room temperature, it remains viable up to 24 hours after performing orchiectomy, and could be subsequently used for artificial insemination AI 3. Retrograde flushing is considered a fast meixco efficient procedure for the recovery of epididymis tail sperm in the equine species.
With this procedure, a recovery of sperm similar to that obtained in ejaculates collected through artificial vagina is reported 4,3. The success of epididymal sperm collections with resulting pregnancies has been reported in different animal species, including man.
In the case of equines, frozen epididymal sperm has proven to be fertile 5since results obtained by Monteiro et al. It has been seen that AI with frozen semen is an essential part in the breeding and selection programs, thereby contributing to increase the production of domestic species 7.
In the case of post-mortem collection equine species, they often need to be preserved for future use, because females are not always available to produce the necessary oocytes for fertilization, due to their characteristics in the estrous cycle 2. Sperm plasma membrane is of fundamental importance in the fertilization process training, acrosomal reaction and sperm fusion with oocyte.
During semen cryopreservation, alterations of the membrane boovina produced causing a decrease in sperm viability 8.
There are reports indicating that equine sperm is severely damaged during freezing and boivna more than the Besides, that sperm that still alive but having an acrosomal reaction AR is not functional to penetrate the oocyte and loses its fertilizing capacity 9.
There are evidences reporting at epididymis level the presence of substances causing modifications in the sperm membrane. One of these substances is inmovilina, which is espongifofme high molecular weight glycoprotein that increases epididymal fluid viscosity and thus reduces sperm cell motility. It also raises an inhibition of the phosphodiesterase activity and changes in cAMP levels, which together help to provide greater resistance to cold shock, compared with ejaculated sperm, thus proving more resistant to cooling and freezing procedures that epididymal sperm 4, 3.
A generally accepted criterion for using post-thaw ejaculated semen of horses is that this must present a motility between Epsongiforme Shulman et al. Considering the above, and due to there are not reports in Mexico in which parameters of potential viability in equine epididymal sperm are registered, the objective of this study was to evaluate the characteristics of equine sperm taken from the epididymis tail, fresh and cryopreserved for possible use in assisted reproduction procedures.
They were collected immediately after slaughter and were linked to the pampiniform plexus level and placed in polyethylene bags containing 10 mL of physiological saline solution at 0.
To obtain sperm, epididymis tail was carefully dissected, including deferens vessel; and later a retrograde flushing was made from the deferens duct by introducing gauge needle inserted at the entrance of the deferens duct.
Gently washing was performed 5,13 with 10 ml of diluent INRA 82 previously prepared with: Finally, 5 mL of air were introduced to facilitate the complete emptying of the epididymis tail content.
The sperm sample was deposited into sterile collectior tubes of 15 mL.
Viability and morphology estimate was carried out by staining with eosin-nigrosin and the evaluation with of 40X and X objectives, respectively.
Bocina in fresh semen or post-thaw semen for each sample, spermatozoa were counted 13,15, The concentration of the samples was evaluated by counting in a Neubauer chamber 2. The viability and acrosomal status of sperm obtained from equine epididymis tail were determined in fresh and post-thaw stage by using the double staining technique of fluorescein isothiocyanate with Arachis hypogea FITC-PNA and propidium iodide PIaccording to the procedure of Garcia-Rosello et al.
The functional status of spermatozoa per sample was evaluated and classified according to the following staining patterns: In order to determine the acrosomal stage, the filter-grade B-2A with excitation degree of nm was used; and to evaluate sperm viability, the G-2A filter with excitation degree of nm was used.
The samples considered acceptable for cryopreservation were left in the cold room for 2 hours, to later add the second diluent of freezing INRA Then an equilibration period of 2 hours was given.
Finally semen was packaged in 0. Data were analyzed with SPSS The progressive motility of equine epididymis sperm in fresh samples obtained in this study was of At thaw, a motility of This value in the progressive motility may result from the freezing protocol used in the assay since the diluent with glycerol was added in one step at 2 hours of cooling, unlike James 2 who added glycerol in fractions of 0.
On the other hand, Monteiro et al. The most widely used parameter as fertility predictor for AI in horses is the individual motility of post-thaw spermatozoa, existing reports in which there is an acceptable motility of at least In this research, an average motility of The viability percentage assessed by eosin-nigrosin staining This difference may be due to two causes: Nevertheless, this author reports having observed thawing of viable sperm The percentage of normal morphology found in the samples before and after freezing was However, in this study, it was only taken into account that sperm presented primary and secondary abnormalities, while Heise et al.
In any assisted reproductive procedure, the main objective is the use of viable sperm having a high potential for fertilization, and in the case of choosing spermatozoa, the best option is to select those that are alive and without RA. This study found a But these authors only mention the presence of the intact acrosome without specifying whether they are alive or dead. Regarding thawed samples, there is a Likewise Papa et al.
On the other hand, this value is also comparable to data from ejaculated sperm, since Graham 22 reported a range of Based on the results obtained in this study, the potentiality of sperm obtained from equine post freezing epididymis can be considered to be used in biotechnological applications of assisted reproduction.
Collection and freezing of epididymal stallion sperm.
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Preservation of sperm harvested from the rat, caprine, equine and bovine epididymis. Freezing of stallion epidymal sperm. Cryopreservation and fertility of ejaculated and epididymal stallion sperm. A comparison of electroejaculated and epididymal sperm collection techniques in stallions.
Hysteroscopic insemination of mares with esopngiforme epididymal spermatozoa. Cryopreservation of domestic animal sperm cells.
Acrosome reaction of stallion spermatozoa evaluated with monoclonal antibody and zona-free hamster eggs. Membrane changes during different stages of a freeze-thawed for equine semen cryopreservation.
Assessing the potential fertility of frozen stallion semen.
Effects of halothane anaesthesia on the cryopreservation of epididymal spermatozoa in pony stallions. Comparison of three different extenders for epididymal stallion sperm.
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Influence of seminal plasma on fresh and post-thaw parameters of stallion epididymal spermatozoa. Application esopngiforme techniques for sperm selection in fresh and frozen-thawed stallion semen. Influence of sperm pretreatment on the efficiency of intracytoplasmic sperm injection in pigs.
Effect of cryopreservation protocol on post-thaw characteristics of stallion sperm. Current methods for stallion semen cryopreservation: Assessment of sperm quality: