Search

Made available in DSpace on 2019-10-05T06:21:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-12-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Eighteen semen samples from nine Santa Ines rams were cryopreserved in order to study the cryoprotective capacity of dimethylacetamide (DMA) at two concentrations (3% and 6%), and its interaction with trehalose (TRE, 100 mOsmol). A further objective of this study was to evaluate in vivo fertility of ram semen cryopreserved with dimethylacetamide. The control treatment was an extender medium with 6% glycerol (GLY). Five treatments were examined: 6% GLY, 3% DMA, 6% DMA, 3% DMA + TRE, and 6% DMA + TRE. After thawing, the kinetic sperm parameters were analyzed using a computerized system. Sperm viability was observed using a multiple parameter sperm staining with propidium iodide (for plasmatic membrane integrity), JC-1 (for mitochondrial membrane potential), and FITC-PSA (for acrosomal integrity). The isosmotic extender with GLY was the most effective medium for the maintenance of sperm characteristics, compared to extenders containing DMA as cryoprotectant. Regarding fertility, the extender medium with 3% DMA may be a safe alternative for sperm cryopreservation, and does not compromise the fertility rates. The addition of TRE decreased the kinetic sperm parameters; however, a positive effect on the integrity of the plasmatic and acrosomal membranes was observed. Univ Fed Bahia, Sch Vet & Anim Sci Med, Ave Adhemar de Barros 500, BR-40170110 Salvador, BA, Brazil Sao Paulo State Univ, Coll Vet Med & Anim Sci, BR-18618000 Botucatu, SP, Brazil Embrapa Coastal Tablelands, Anim Reprod Biotechnol Lab, Ave Beira Mar 3250, BR-49025040 Aracaju, Sergipe, Brazil Sao Paulo State Univ, Coll Vet Med & Anim Sci, BR-18618000 Botucatu, SP, Brazil

Made available in DSpace on 2015-08-26T19:19:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-03-01. Added 1 bitstream(s) on 2015-08-31T13:04:41Z : No. of bitstreams: 1 S1809-68912015000100125.pdf: 325800 bytes, checksum: df99c67e7a96f096a76ada1ad30fe97a (MD5) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Este trabalho teve como objetivo avaliar a eficiência de gradientes de densidade contínuos de Percoll e OptiPrep para a separação de espermatozoides portadores do cromossomo X, e avaliar a influência sobre a viabilidade espermática, taxa de prenhez e proporção do sexo. Para isso, 100 milhões de espermatozoides foram depositados em cada tubo contendo o gradiente de densidade, previamente preparados, em tubos de poliestireno, 24 horas antes da centrifugação e mantidos a 4 °C. Centrifugou-se a 500 x g por 15 minutos a 22 °C e, posteriormente, os sobrenadantes foram aspirados e os espermatozoides recuperados no fundo dos tubos. Uma amostra foi avaliada antes a após a centrifugação para verificação da motilidade e vigor espermático. Os espermatozoides foram utilizados para a inseminação artificial em tempo fixo. Os resultados indicaram que a centrifugação não afetou a viabilidade espermática e a taxa de prenhez, entretanto não houve desvio da proporção do sexo para fêmeas. Mais estudos são necessários para determinar a necessidade de adaptação da técnica de centrifugação para a espécie ovina e assim obter o desvio da proporção do sexo como na espécie bovina. The objective of this study was to evaluate the efficiency of continuous density gradients of Percoll and OptiPrep for separation of X-bearing sperm, and assess the influence on sperm viability, pregnancy rate and sex ratio. With this purpose 100 million spermatozoa were deposited into each tube containing density gradient, which were previously prepared in polystyrene tubes, 24 hours before centrifugation and stored at 4 °C. The tubes were centrifuged at 500xg for 15 minutes at 22 °C, and then the supernatants aspirated and sperm recovered from the bottom of the tubes. A sample was evaluated before and after centrifugation to verify motility and sperm vigor. The sperm were used for fixed time artificial insemination. The results indicated that centrifugation did not affect sperm viability and pregnancy rate, however there was no deviation of sex ratio for females. More studies are needed of adapting the centrifugation technique to sheep and thus obtain the deviation of sex ration as in bovine. Universidade Estadual Paulista, Departamento de Medicina Veterinária Preventiva e Reprodução Animal, Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal CAPES: 23038.007863/2008-47

The aim of this study was to evaluate the immuno-sterilizing action of anti-gonadotrophin-releasing hormone (anti-GnRH) vaccine in goats. Eighteen male goats were randomly distributed to receive three treatments: T1 (control) - whole animals, and T2 and T3 - application of 0.5 and 1.0 mL of anti-GnRH vaccine, respectively, with six replicates and one goat per experimental unit. Vaccine was administered at 8 months of age and 30 days after the first immunization. Testicular biometry was evaluated monthly, along with seminal collections, for the physical and morphological evaluation of semen. At the time of slaughter, the testicle were collected, and fragments were measured and removed for histological evaluation. The data were evaluated for normality by the Shapiro-Wilk test, followed by appropriate statistical tests for each variable. A reduction in width and length of the right and left testicles was observed and, consequently, the scrotal circumference of the immunized animals reduced after the second vaccine application (P 0.05). Thirty-days after the first vaccine application, there was a negative effect on seminal production and quality; and 60 days after the second application, a pronounced reduction was observed in all seminal parameters in the vaccinated animals, including azoospermia (83.33% of animals; P 0.05). Vaccine application reduced testicular weight, seminiferous tubule diameter, and gonadosomatic and tubulosomatic index (P 0.05), but did not influence the proportion of testicular parenchyma components (P 0.05). Two applications of the anti-GnRH conjugate are effective for the immunological castration of goats, and the 0.5 mL dose is recommended for use in crossbred goats.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:23:48Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:40:55Z : No. of bitstreams: 1 2-s2.0-78149372698.pdf: 504168 bytes, checksum: 89fa109b73bc35f914c2377b2c393644 (MD5) Made available in DSpace on 2014-05-27T11:23:48Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-12-01 The aim of this paper was verifying the effect of the Equex STM Paste and EDTA addition to a Tris-egg yolk extender, on the postthaw goat sperm viability. Nine semen samples of two adult goats were collected by artificial vagina and cryopreserved. It was also objective of this study, to evaluate the utilization of a soybean lecithin based commercial extender (Bioexcell® - IMV, L'Aigle, French) for the goat semen freezing. They were formed five experimental groups: TRIS; TRIS+EDTA; TRIS+EQUEX; TRIS+EDTA+EQUEX e Bioexcell. After evaluation, the semen was diluted in the five extenders and packed in 0.25mL straws with 100 million of motile spermatozoa. The samples were cooled at 0,46°C/min to 5°C, submitted at 75min of equilibration time and frozen in liquid nitrogen vapour. The thawing was accomplished in 37°C water bath for 50s. There were no differences (P>0,05) on the means of post-thaw total and progressive sperm motility among the groups TRIS, TRIS+EQUEX and TRIS+EQUEX+EDTA. The Bioexcell group obtained the least (P

Eleven semen samples from Santa Ines breed rams were cryopreserved with the objective of studying the effect of the dimethyl acetamide (DMA, 3%) or glycerol (GL, 6%) in an extender (Tris) with or without trehalose (TRE, 100 mOsmol) on post-thaw sperm viability and fertility. After the evaluation, the semen was diluted in extenders (TRIS+GL6%; TRIS+GL6%+TRE; TRIS+DMA3%; Tris+DMA3%+TRE) and then frozen. The post-thaw kinetic sperm parameters evaluated were the percentage of total motility (TM) and rapid spermatozoa (RAP), track speed (VCL), lateral amplitude of head (ALH), and linearity (LIN). The sperm viability was verified using the fluorescence markers propidium iodide (PMI, plasmatic membrane integrity), JC-1 (MMP, mitochondrial membrane potential), and FITC-PSA (ACI, acrosomal integrity). The spectrum of DNA sperm damage was assessed by single cell gel electrophoresis (Comet assay), and the measurements performed were tail moment (TMOM) and tail intensity (TINT; Comet Assay II software, Perceptive Instruments, Haverhill, UK). The sheep estrus synchronization protocol (n = 170) was 12 days of sponge with 60 mg of medroxyprogesterone acetate and 300 UI of eCG i.m. at sponge withdrawal. The ewes were inseminated on 57.5 h after sponge removal with 150 × 106 of live spermatozoa. The conception rates (CR) were verified for ultrasonography 45 days after insemination. The statistical analysis was performed using SAS software (SAS Institute Inc., Cary, NC, USA). The means (±SEM) of in vitro post-thaw sperm parameters and fertility rates are shown in Table 1. The greatest (P < 0.05) rates of TM and RAP for the GLY groups were observed in relation to the DMA ones. It was also verified the inferiority (P < 0.05) in the VCL and ALH for the trehalose extenders in both groups with GLY and DMA. The values (%) of TINT and TMOM were 14.9 and 03.9, 15.8 and 03.8, 14.7 and 02.9, and 16.6 and 04.4, respectively, for TRIS+GL6%, TRIS+GL6%+TRE, TRIS+DMA3%, and TRIS+DMA3%+TRE (P > 0.05). The integrity rates of all sperm membranes were superior for TRIS+GL6% in relation to TRIS+DMA3%. In conclusion, the DMA had apoor cryoprotective effect for ram semen. The addition of trehalose promoted negative effect on sperm kinetics, although it improved levels of PMM post-thawing in the DMA extender. The conception rate did not present a difference (P > 0.05) among the groups. Table 1.