Differential surface glycoprofile of buffalo bull spermatozoa during mating and non-mating periods

The buffalo has a seasonal reproduction activity with mating and non-mating periods occurring from late autumn to winter and from late spring to beginning of autumn, respectively. Sperm glycocalyx plays an important role in reproduction as it is the first interface between sperm and environment. Semen quality is poorer during non-mating periods, so we aimed to evaluate if there were also seasonal differences in the surface glycosylation pattern of mating period spermatozoa (MPS) compared with non-mating period spermatozoa (NMPS). The complexity of carbohydrate structures makes their analysis challenging, and recently the high-throughput microarray approach is now providing a new tool into the evaluation of cell glycosylation status. We adopted a novel procedure in which spermatozoa was spotted on microarray slides, incubated with a panel of 12 biotinylated lectins and Cy3-conjugated streptavidin, and then signal intensity was detected using a microarray scanner. Both MPS and NMPS microarrays reacted with all the lectins and revealed that the expression of (i) O-glycans with NeuNAcα2-3Galβ1,3(±NeuNAcα2-6)GalNAc, Galβ1,3GalNAc and GalNAcα1,3(l-Fucα1,2)Galβ1,3/4GlcNAcβ1 was not season dependent; (ii) O-linked glycans terminating with GalNAc, asialo N-linked glycans terminating with Galβ1,4GlcNAc, GlcNAc, as well as α1,6 and α1,2-linked fucosylated oligosaccharides was predominant in MPS; (iii) high mannose- and biantennary complex types N-glycans terminating with α2,6 sialic acids and terminal galactose were lower in MPS. Overall, this innovative cell microarray method was able to identify specific glycosylation changes that occur on buffalo bull sperm surface during the mating and non-mating periods

Therapeutic Ultrasound as a Potential Male Dog Contraceptive: Determination of the Most Effective Application Protocol

Contents: Ultrasound is one of the most promising forms of non-invasive contraception and has been studied in several animal models. The objective of the current investigation was to determine the most practical and effective application protocol for dog sterilization. A total of 100 dogs were divided into five equal groups. Group A received 5-min applications three times performed at 48-hr intervals and covering the entire testicular area at frequency of 1 MHz; Group B received 5-min applications three times performed at 48-hr intervals over the dorso-cranial area of the testis at frequency of 3 MHz; Group C received three sequential 5-min applications (at 5-min intervals between applications) covering the entire testicular area at frequency of 1 MHz; Group D received 15-min applications two times performed at 48-hr intervals and covering the entire testicular area at frequency of 1 MHz. The experimental groups' ultrasound had an intensity of 1.5W/cm2. The Control Group had the same procedure as Group A, but with the transducer switched-off. Dogs were surgically castrated 40 days following the treatment for histological examination. Azoospermia, testicular volume reduction and apparently irreversible testicular damage were achieved by Group A. No effects were noticed in the other groups. Testosterone levels remained within physiological range with all application protocols. A regimen of three applications of ultrasound at 1 MHz, and 1.5 W/cm2, lasting 5 min with an interval of 48 h was effective as permanent sterilization in the dog without hormonal impact

Chemical castration by intra-testicular injection of acalcium chloride in alcohol solution in dogs

An affordable and effective non-surgical technique for achieving male dog sterility is needed to solve the problem of overpopulation. The efficacy of 20% calcium chloride in pure alcohol solution, injected into the testicular parenchyma, as a method for chemical castration, was evaluated. Twenty-one dogs of mixed breed, 4.7 ± 1.23 years old, 20 ± 5.84 kg of body weight, with good clinical conditions and normal reproductive parameters, were lightly sedated and injected into the dorsocranial portion of both testes with a solution of 20% calcium chloride dihyrdate in ethanol (95%). The dose injected corresponds with the testicular width (19–22 mm receive 0.8 ml; 23 and above 1 ml). Semen evaluation was performed by CASA (Computer Assisted Sperm Analysis) system at day 30–60–90. The animals in the control group received a single bilateral intratesticular injection of 1 ml sterile saline solution (testicular width 23 mm and above). Forty-eight hours after the injection, dogs showed very light discomfort at palpation and testicular tumefaction, which regressed within 3 days. At day 30, testicular ultrasonography revealed bilateral more dense nodular lesions; prostatic volume and parenchyma were normal. Semen evaluation showed azoospermia at day 30–60 and 90. The sperm count was decreased significantly (p < 01) in all the CaCl2 treated dogs in comparison to saline solution control animals. At day 90 testicles were shrunk at palpation. An intratesticular injection of 20% calcium chloride in pure alcohol solution, as a method for chemical castration, was effective and economical for the sterilization of male dogs. It is free from pain and chronic stress and will contribute to a simple alternative method to surgical castration. The dogs of this study are under evaluation to study this solution long term effect (1 year)