2011 (SBTE) 25th Annual Meeting Proceedings - International ...

Acta Scientiae Veterinariae, 2011. 39(Suppl 1): Abstracts - 25th Annual Meeting SBTE-Brazil. August 2011.
A027 MALE REPRODUCTIVE PHYSIOLOGY AND SEMEN TECHNOLOGY
EFFECT OF PORCINE SOMATOTR
TROPIN (PST) ) ON TESTICULAR MORPHOLOGIC
OGICAL AND FUNCTIONAL CHARACTERISTICS
CTERISTICS
FROM PREPUBERTAL BOARS
Douglas Perazzoli, , Dante Ferrari Frigotto, Clairton Marcolongo Pereira, Viviane Rohrig Rabassa, Ivan Bianchi, Eduardo Schmitt & Marcio Nunes Corrêa
UNIVERSIDADE FEDERAL DE PELOTAS, PELOTAS, RS, BRAZIL.
The influence of exogenous growth hormone (GH) on testicular development has been characterized in several species; however,
it is not well understood in boars. The aim of this work was to determine the effect of exogenous GH on testicular morphological and functional
characteristics from prepubertal boars. In this study, 12 boars with 22 to 53 days of age were used. The animals were divided in two groups: GH
Group (n = 6), which received 90 µg/Kg of porcine somatotropin (pST, Reporcin ® , Zamira Life Sciences Pty Ltd., Melbourne, Australia) every
3 days; and Control Group (n=6), that received placebo injections (sodium chloride 0.9%) at the same interval. The boars were weighed every
3 days to adjust pST dose. Orchietomy was performed when the boars reached 53 days of age. The testes were weighed to determine the
gonadosomatic index, which is the relation between body weight and testes weight (%). Moreover, the central portion of the testicular
parenchyma was sampled and stored in 10%formoline for immunohistochemical analysis. The monoclonal antibody Ki67 was used to identify
germinative cells in proliferation and Vimentin was used to identify Sertoli cells. Cells were counted using ImageJ (ver.1.44, National Institutes
of Health, Bethesda, USA). Statistical analysis was perfomed by analisys of variance with Tukey adjustment using SAS (SAS Institute Inc,
USA). The number of Sertoli cells was higher in Control than GH Group (GH: 209.5 ± 12.3; Control: 372.0 ± 41.6; P = 0.0004). The same
difference was found for the seminiferous tubules (GH: 28.7 ± 1.5; Control: 35.1 ± 1.3; P = 0.002). However, the diameter of the seminiferous
tubules (GH: 202.9 ± 1.8; Control: 199.1 ± 1.8; P = 0.15), number of proliferating germinative cells (GH: 30.6 ± 3.2; Control: 32.3 ± 1.7; P =
0.65) and gonadosomatic index (GH: 0.07 ± 0.01; Control: 0.08 ± 0.01; P = 0.38) were not different between groups. In conclusion, the use of
pST in prepubertal boars reduced the number of Sertoli cells and seminiferous tubules, without affecting, however, the diameter of seminiferous
tubules, number of germinative cells and gonadosomatic index.
Keywords: exogenous growth hormone, testes, prepubertal boars.
A028 MALE REPRODUCTIVE PHYSIOLOGY AND SEMEN TECHNOLOGY
EFFECT OF DIFFERENT CONCENTR
ONCENTRATIONS TIONS OF REDUCED GLUT
UTATHIONE THIONE (GSH) FOR CRYOPRESER
OPRESERVATION OF
CANINE SPERM
Camila Infantosi Vannucchi , Cristina Fátima Lucio, Liege Garcia Silva, Fernanda Machado Regazzi, Daniel Souza Ramos Angrimani,
Marcílio Nichi & Valquiria Hyppolito Barnabe
DEPARTAMENTO DE REPRODUÇÃO ANIMAL, UNIVERSIDADE DE SÃO PAULO, SÃO PAULO, SP, BRAZIL.
Sperm cells are particularly susceptible to oxidative stress as their plasma membrane contains large amounts of polyunsaturated fatty
acids and their cytoplasm has a low concentration of protective enzymes. The process of sperm cryopreservation induces the formation of free
radicals, thereby diminishing sperm performance. Supplementation of the extender for cryopreservation with antioxidants may improve sperm
quality after thawing. This study aimed to compare different concentrations of reduced glutathione (0, 10 and 20 mM GSH) in the extender for
cryopreservation of canine semen. Eleven ejaculates were collected from 6 dogs and the samples were divided equivalently in three groups:
GLU10 (10 mM glutathione), GLU20 (20 mM glutathione) and Control Group (CG - without antioxidant). The fresh and pos-thaw semen
samples were evaluated for motility and vigor, computerized motility analysis (CASA), percentage of live sperm through eosin/nigrosin stain,
oxidative stress by TBARS concentration, mitochondrial activity by the DAB staining, mitochondrial membrane potential by JC1 probe and
membrane integrity by FITC/PI probes using flow cytometry. The variables were compared among groups by ANOVA and LSD at P < 0.05.
The subjective motility suffered a significant reduction in the post-thaw treated groups and the vigor decreased only in the GLU20 group. The
computerized assessment of motility detected a significant decrease in total and progressive motility in GLU20 group, with increased number of
static sperm in relation to CG. There was a decrease in mitochondrial activity assessed by DAB of the GLU20 group. We observed a protective
effect of the antioxidant supplementation, as the probes FITC / PI detected a lower percentage of acrosomal damage in the GLU20 and GLU10
groups. No differences were observed for the assessment of JC1 and TBARS among the proposed groups. In conclusion, the addition of
reduced glutathione in the semen extender presented a protective effect for the acrosome of the canine sperm. However, due to decrease in sperm
motility, different concentrations of this antioxidant must be tested in order to detect the beneficial effects, without any pro-oxidative action.
[FAPESP 09/52760-3].
Keywords: antioxidants, sperm, canine.
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