RESUMO
A fisiologia reprodutiva da espécie canina e a resposta insatisfatória do sêmen do cão à técnica da congelação são os dois maiores empecilhos aos esforços para o avanço da inseminação artificial em cães. Inúmeras pesquisas estão sendo desenvolvidas nessa área, gerando muitas informações, sobretudo na tecnologia de sêmen. O objetivo desse texto é discutir os principais avanços na avaliação e congelação de sêmen e sua influencia nos resultados de inseminação artificial.
The canine reproductive physiology and unsatisfactory results on techniques of frozen dog semen has been the biggest barrier on the improvement of artificial insemination in dogs. Many researches are been done in this area generating a lot of information, especially on semen technology. The aim of this text is to discuss the major advances on semen evaluation and semen frozen and its influence on artificial insemination results.
Assuntos
Animais , Cães , Inseminação Artificial/tendências , Preservação do Sêmen/tendências , Reprodução/fisiologia , SêmenRESUMO
A fisiologia reprodutiva da espécie canina e a resposta insatisfatória do sêmen do cão à técnica da congelação são os dois maiores empecilhos aos esforços para o avanço da inseminação artificial em cães. Inúmeras pesquisas estão sendo desenvolvidas nessa área, gerando muitas informações, sobretudo na tecnologia de sêmen. O objetivo desse texto é discutir os principais avanços na avaliação e congelação de sêmen e sua influencia nos resultados de inseminação artificial.(AU)
The canine reproductive physiology and unsatisfactory results on techniques of frozen dog semen has been the biggest barrier on the improvement of artificial insemination in dogs. Many researches are been done in this area generating a lot of information, especially on semen technology. The aim of this text is to discuss the major advances on semen evaluation and semen frozen and its influence on artificial insemination results. (AU)
Assuntos
Animais , Cães , Preservação do Sêmen/tendências , Reprodução/fisiologia , Inseminação Artificial/tendências , SêmenRESUMO
Nosso objetivo foi avaliar os efeitos do benzoato de estradiol sobre a taxa de recuperação oocitária e embrionária e sua influência sobre o sistema hematopoiético. Vinte e quatro fêmeas foram utilizadas: GRUPO I – 12 cadelas que receberam uma única aplicação de benzoato de estradiol, dose de 0,2 mg/Kg, via intramuscular, entre o 2º e 7º dia do último acasalamento ou inseminação. GRUPO II - 12 cadelas que receberam solução oleosa diluente, dose de 0,2 ml/Kg em datas correspondentes. As cadelas foram submetidas a ovariohisterectomia e as tubas uterinas e útero lavados, com solução de PBS, álcool polivinil e heparina. Os oócitos e embriões foram quantificados e classificados de acordo com seu estádio de desenvolvimento. O hemograma foi realizado em M1 (antes da aplicação do fármaco), M2 (15 dias após a aplicação do fármaco) e M3 (40 dias após a aplicação do fármaco). Para as variáveis recuperação de estruturas foi utilizado o coeficiente de correlaç&at
RESUMO
The objective of this work was to describe the presence of osteopontin (OPN) in canine seminal plasma and sperm membranes. A pool of seminal plasma and sperm membrane extract from 30 dogs was used. Polyacrylamide electrophoresis gels were performed and the bands were transferred to nitrocellulose paper and Western blot was undertaken using an antibody anti-OPN. Two and 12 bands were marked in the seminal plasma (77.2 and 15.6 kDa) and sperm membrane extracts (70.6-26.6 kDa), respectively. However, from 12 marked bands in the sperm membrane extract, only three (46.4, 37.7 and 36.5 kDa) were strongly marked. We conclude that, seminal plasma and sperm membranes from dogs contain different isoforms of OPN; yet, further studies will be necessary to determine their function in this species.
Assuntos
Membrana Celular/metabolismo , Cães , Osteopontina/metabolismo , Sêmen/química , Espermatozoides/citologia , Espermatozoides/fisiologia , Animais , Masculino , Isoformas de ProteínasRESUMO
The aim of present study was to evaluate frozen canine semen with ACP-106 (Powder Coconut Water) using an in vitro sperm--oocyte interaction assay (SOIA). Ten ejaculates from five stud dogs were diluted in ACP-106 containing 20% egg yolk, submitted to cooling in a thermal box for 40 min and in a refrigerator for 30 min. After this period, a second dilution was performed using ACP-106 containing 20% egg yolk and 12% glycerol. Samples were thawed at 38 degrees C for 1 min. Post-thaw motility was evaluated by light microscopy and by using a computer aided semen analysis (CASA). Plasma membrane integrity and sperm morphology/acrosomal status were evaluated by fluorescent probes (C-FDA/PI) and Bengal Rose respectively. Moreover, frozen-thawed semen was analysed by a SOIA. Subjective post-thaw motility was 52.0 +/- 14.8% and it was significant higher than the total motility estimated by CASA (23.0 +/- 14.8%) because this system considered the egg yolk debris as immotile spermatozoa. Although normal sperm rate and acrosomal integrity evaluated by Bengal Rose stain was 89.6 +/- 3.1% and 94.3 +/- 3.1%, respectively, post-thaw percentage of intact plasma membrane was only 35.1 +/- 14.3%. Regarding SOIA, the percentage of interacted oocytes (bound, penetrated and bound and/or penetrated) was 75.3%. Using regression analysis, it was found significant relations between some CASA patterns and data for SOIA. In conclusion, the freezing-thawing procedure using ACP-106 was efficient for maintain the in vitro fertility potential of dog spermatozoa.
Assuntos
Criopreservação/veterinária , Crioprotetores/farmacologia , Cães , Preservação do Sêmen/veterinária , Interações Espermatozoide-Óvulo/fisiologia , Espermatozoides/fisiologia , Acrossomo/fisiologia , Animais , Meios de Cultura/química , Cães/fisiologia , Citometria de Fluxo , Masculino , Preservação do Sêmen/métodos , Motilidade dos EspermatozoidesRESUMO
Frozen-thawed epididymal spermatozoa have already been successfully used in artificial insemination in the domestic cat, proving to be a valuable resource for the reproduction of felid species, which are threatened with extinction. The aim of this study was to compare the effects of freezing and thawing on domestic cat semen collected by electroejaculation (EL) and from the epididymides (EP) and vasa deferentia. Ten adult cats were anesthetized, electroejaculated and immediately thereafter, orchiectomized. Epididymal spermatozoa were collected through the compression of caudae epididymidis and vasa deferentia. Spermatozoa were frozen-thawed following a single protocol. Sperm motility, sperm progressive status (0-5), plasma membrane integrity and morphology (light and transmission electron microscope) were assessed on two occasions, immediately after collection and after freezing and thawing. There were no significant differences between the electroejaculated and epididymal fresh or frozen-thawed spermatozoa for any of the variables. However, the incidence of acrosome defects after freezing and thawing increased by 19% based on light microscopy, whereas ultrastructural images revealed acrosome damages in most sperm cells. Since these acrosomal changes are known to affect sperm fertilising capacity, further studies are needed to optimize cryopreservation techniques for epididymal as well as electroejaculated domestic cat spermatozoa.