A Low-fidelity Simulator for the Development of Vascular Ligation Skills.

Training simulators can facilitate the acquisition and development of basic surgical skills, and they constitute a safe and humane method that does not harm animals in the process. The objective of this work was to create and evaluate a low-cost simulator to help undergraduate students of veterinary medicine acquire and practise vascular ligation skills. A training model was made by using easily accessible and inexpensive materials. Fifteen students, without prior surgical experience, each performed the orchiectomy technique on the simulator seven times. The emphasis was on performing vascular ligatures in both testicles of the simulator (n = 14), in two different scenarios: firstly, with the contents of the blood vessels not under pressure; and secondly, with the syringe plunger depressed by 1 ml to pressurise the blood vessels. The outcomes of the procedure in the simulator were based on three qualitative criteria: Correct (no 'bleeding'), Sufficient (light 'bleeding') and Incorrect (heavy 'bleeding'). After the seventh attempt, all participants were able to perform vascular ligatures with at least a score of Sufficient in both scenarios. By the 10th ligature attempt, they were all able to perform the procedure with a score of Correct (p < 0.05). There was a trend toward a decrease in the time taken to carry out the procedure as learning progress was made during training, with this being significant from the 12th attempt (p < 0.05). The use of this low-cost simulator represents a useful didactic tool, which supports the acquisition and practise of manual skills by using methods that do not involve the use of animals. In addition, this training simulator could be useful in distance learning, in view of the ready accessibility of the materials required for its construction.

Potential fertilizer of spermatozoa in porcine epididymal tail post-orchiectomy.

The aim of this study was to determine the potential fertilizing of spermatozoa from the epididymal tail in different periods of time post-orchiectomy (P-OQ). Therefore, the study was approached in two stages. In the first stage, the orchiectomy was performed in 30 adult pigs. The testicles were stored at 5.00 ˚C in physiological saline solution for 5, 24, 48, 72, 96 and 120 hr. The spermatozoa were obtained by backflushing the vas deferens. The spermogram and fluorometric study were performed for each sample to evaluate the exposure of phosphatidyl-serine (PS) and acrosome reaction (AR). The second stage included the fertilization test, 16 prepubertal sows were selected, after synchronizing the oestrous cycle and the post-cervical artificial insemination was performed with the refrigerated sperm samples from each P-OQ time. The percentage of live sperm remained without significant changes until 96 hr P-OQ. An increase in the percentage of spermatozoa that showed a PS exposure was observed. The premature AR was evident after 72 hr. Considering that the artificial insemination was performed ensuring a minimum number of live sperms, no significant differences were observed in the number of embryos and corpora lutea. The results indicated that pig sperm collected from the epididymal tail P-OQ and stored for 5 and up to 72 hr at 5.00 ˚C had viable characteristics and maintained their fertilization ability. However, there was an increase in the loss of phospholipid asymmetry of the plasma membrane as time increased (72 and 96 hr), therefore, sperm viability was decreased.

Viability of in vitro preserved sperm of Harris's hawk (Parabuteo unicinctus).

Harris hawks (Parabuteo unicinctus) are the raptors with more anthropogenic use, which makes it necessary to improve their reproduction either natural or assisted for sustainable use even though they are not endangered. The aim of this study was to determine fresh and thawed P. unicinctus sperm capacitation and acrosome reaction parameters as indicators of sperm viability in ejaculates of birds with injuries. A total of 30 ejaculates were analyzed as fresh and thawed samples. Basic sperm evaluations as well as in vitro acrosomal reaction capability through the presence and distribution of Ca2+ and N-acetylglucosamine and sialic acid using chlortetracycline and agglutinin-fluorescein isothiocyanate Triticum vulgaris were performed, respectively. Tagged samples were observed using epifluorescence microscopy. The results indicated 30.00% decrease in sperm viability following freeze-thaw, while rate of capacitated sperms (10.00%) and the percentage of sperm with acrosomal reaction (40.00%) were increased. The results of the experiment demonstrated that the post-thaw viability of the obtained sperm may be an alternative for use in artificial insemination.

Harris's hawks (Parabuteo unicinctus) hematological parameters in different tropical locations.

This work described and compared the hematological findings of 25 clinically healthy Harris's hawks (Parabuteo unicinctus) in captivity at two different tropical locations: 16 samples from Aguascalientes, which altitude is 1878 mean sea level, and nine samples from Amecameca which altitude is 2650 mean sea level. Blood samples were collected from the brachial vein of each raptor under physical restraint. Significant differences between the two locations were found in some parameters including total, erythrocytes, heterophils, basophils, lymphocytes, and heterophil/lymphocyte ratio. When the results were compared to the reference values, the population of Amecameca showed decreased values of hematocrit (32.21 ± 13.72%), hemoglobin (107.40 ± 45.60 g L-1) and erythrocytes (1.98 ± 0.63 ×1012 per µL). This work contributed to the knowledge of variations in blood parameters of clinically healthy captive Harris`s hawks at different tropical locations and sex. The information will enable clinicians to provide appropriate veterinary diagnostics and care to ensure the health and welfare of raptors kept in captivity.

Testicular development induced by GnRH-IS in budgerigar (Melopsittacus undulatus).

Nowadays, the third part of parrots in the world is endangered or vulnerable; an alternative for their preservation is assisted reproduction in captivity through hormonal manipulation. In birds, GnRH is the main hormone which controls reproductive physiology, it is known there are three types: GnRH-I, GnRH-II and GnRH-III, involved in the release or inhibition of luteinizing hormone and follicle stimulant hormone to control gonadal and gametic development. The objective of this study was, to evaluate the effect of administrating synthetic GnRH-I in the testicular development of Melopsittacus undulatus. Twenty-eight adult budgerigars were randomly divided in two groups: control (n=14) and treated (n=14) with a unique dose of synthetic GnRH-I. Testicular development was assessed through ultrasonography and density was evaluated with pixels. Germinal diameter and thickness of germinal epithelium were determined with histology; there were identified and countified different cellular strains in seminiferous tubules therefore spermatobioscopy. Results. Ecographic density was: control group: 76 ± 7 pixels, treated group 41 ± 3 pixels. Thickness of germinal epitellium, 51.5 ± 2.9µm and 73.1 ± 3.1µm, for control group and treated group respectively. Sperm concentration in the treated group was 300% superior than in control group. It is concluded that the administration of synthetic GnRH-I, is a viable alternative to be used as part of the assisted reproductive techniques to induce reproduction.