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1.
Waste Manag Res ; 28(6): 520-32, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19748958

RESUMO

Lack of consistent and available information for the entire tyre industry has often hindered adequate understanding of current and future issues that need to be addressed for improving the sustainable end-of-life tyre management. The aim of this paper is to review related best available technologies and techniques for Greece, ranging from simple mechanical processing, up to complex multistep, mechanochemical and/or thermal treatment. End-of-life tyre management guidelines in the form of a manual for supporting future entrepreneurs in this field are also discussed. Extensive data mining, classification and inventorying was performed, both in the field via questionnaires and in the literature, for the purpose of accurately determining Hellenic conditions, in order to pinpoint encountered problems, propose interventions and determine new entrepreneurship opportunities.


Assuntos
Manufaturas/análise , Borracha/análise , Gerenciamento de Resíduos , Resíduos/análise , Automóveis , Coleta de Dados , Grécia , Manufaturas/economia , Manufaturas/estatística & dados numéricos , Marketing , Borracha/economia , Resíduos/economia , Resíduos/estatística & dados numéricos
2.
Waste Manag Res ; 28(11): 967-76, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20630941

RESUMO

Renewable energy sources (RES), excluding large hydroelectric plants, currently produce 4.21% of total electricity production in Greece. Even when considering the additional production from large hydroelectric plants, which accounts for some 7.8%, the distance to be covered towards the objective of 20% electricity produced from RES by 2010 and respectively towards 20% of total energy production by 2020 is discouraging. The potential, however, does exist; unfortunately so do serious barriers. On the other hand, solid waste management (SWM) is an issue that generates continuously increasing interest due to the extra amounts of solid waste generated; the lack of existing disposal facilities with adequate infrastructure and integrated management plans, also often accompanied by legislative and institutional gaps. However, socio-economic and public awareness problems are still met in the planning and implementation of RES and SWM projects, together with the lack of a complete national cadastre and a spatial development master plan, specifying areas eligible for RES and SWM development. Specific barriers occur for individual RES and the on-going inclusion of waste-derived renewable energy in the examined palette further increases the complexity of the entire issue. The consolidated study of this broad set of barriers was a main task of the present study which was carried out within the frame of a Hellenic-Canadian research project; the main results will be discussed herein.


Assuntos
Conservação de Recursos Energéticos , Eliminação de Resíduos , Grécia , Opinião Pública , Fatores Socioeconômicos
3.
J Environ Manage ; 90(10): 2999-3012, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19482412

RESUMO

Waste management activities contribute to global greenhouse gas emissions approximately by 4%. In particular the disposal of waste in landfills generates methane that has high global warming potential. Effective mitigation of greenhouse gas emissions is important and could provide environmental benefits and sustainable development, as well as reduce adverse impacts on public health. The European and UK waste policy force sustainable waste management and especially diversion from landfill, through reduction, reuse, recycling and composting, and recovery of value from waste. Energy from waste is a waste management option that could provide diversion from landfill and at the same time save a significant amount of greenhouse gas emissions, since it recovers energy from waste which usually replaces an equivalent amount of energy generated from fossil fuels. Energy from waste is a wide definition and includes technologies such as incineration of waste with energy recovery, or combustion of waste-derived fuels for energy production or advanced thermal treatment of waste with technologies such as gasification and pyrolysis, with energy recovery. The present study assessed the greenhouse gas emission impacts of three technologies that could be used for the treatment of Municipal Solid Waste in order to recover energy from it. These technologies are Mass Burn Incineration with energy recovery, Mechanical Biological Treatment via bio-drying and Mechanical Heat Treatment, which is a relatively new and uninvestigated method, compared to the other two. Mechanical Biological Treatment and Mechanical Heat Treatment can turn Municipal Solid Waste into Solid Recovered Fuel that could be combusted for energy production or replace other fuels in various industrial processes. The analysis showed that performance of these two technologies depends strongly on the final use of the produced fuel and they could produce GHG emissions savings only when there is end market for the fuel. On the other hand Mass Burn Incineration generates greenhouse gas emission savings when it recovers electricity and heat. Moreover the study found that the expected increase on the amount of Municipal Solid Waste treated for energy recovery in England by 2020 could save greenhouse gas emission, if certain Energy from Waste technologies would be applied, under certain conditions.


Assuntos
Efeito Estufa , Eliminação de Resíduos , Gerenciamento de Resíduos/métodos , Conservação de Recursos Energéticos , Inglaterra , Monitoramento Ambiental
4.
Waste Manag ; 29(5): 1754-9, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19216066

RESUMO

This paper deals with the creation of appropriate conditions aimed at developing social services for reuse and recycling of waste electrical and electronic equipment (WEEE), by the inclusion of handicapped and Roma people in the workforce. Application areas for the project are the Hellenic (Greek) regions of Thessaly and North Aegean, where these groups suffer from professional and social exclusion. The efforts to reduce unemployment in the two aforementioned groups, together with the efforts to implement related Greek and European legislation for sustainable WEEE management, are examined here. Furthermore, networking and cooperation at local, regional and central levels between small enterprises, entrepreneurships and local authorities are examined, so that these social enterprises and their corresponding investments may support the development of the Greek alternative WEEE recycling system.


Assuntos
Comércio , Conservação dos Recursos Naturais/métodos , Equipamentos e Provisões Elétricas , Grupos Minoritários , Eliminação de Resíduos/métodos , Serviço Social , Pessoas com Deficiência , Etnicidade , Grécia , Humanos , Inquéritos e Questionários
5.
Waste Manag ; 29(5): 1686-92, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19147341

RESUMO

The present position paper addresses contemporary waste management options, weaknesses and opportunities faced by Hellenic local authorities. It focuses on state-of-the-art, tested as well as innovative, environmental management tools on a municipal scale and identifies a range of different collaboration schemes between local authorities and related service providers. Currently, a policy implementation gap is still experienced among Hellenic local authorities; it appears that administration at the local level is inadequate to manage and implement many of the general policies proposed; identify, collect, monitor and assess relevant data; and safeguard efficient and effective implementation of MSWM practices in the framework of integrated environmental management as well. This shortfall is partly due to the decentralisation of waste management issues to local authorities without a parallel substantial budgetary and capacity support, thus resulting in local activity remaining often disoriented and isolated from national strategies, therefore yielding significant planning and implementation problems and delays against pressing issues at hand as well as loss or poor use of available funds. This paper develops a systemic approach for MSWM at both the household and the non-household level, summarizes state-of-the-art available tools and compiles a set of guidelines for developing waste management master plans at the municipal level. It aims to provide a framework in the MSWM field for municipalities in Greece as well as other countries facing similar problems under often comparable socioeconomic settings.


Assuntos
Cidades , Planejamento de Cidades/métodos , Conservação dos Recursos Naturais/métodos , Modelos Teóricos , Eliminação de Resíduos/métodos , Gerenciamento de Resíduos/métodos , Grécia
6.
Oncogene ; 26(12): 1769-79, 2007 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-16964280

RESUMO

We have isolated a gene (WS5) that is specifically expressed at the mRNA and protein level in avian fibroblasts transformed by the v-myc oncogene of avian acute leukemia virus MC29. In a conditional cell transformation system, WS5 gene expression was tightly correlated with v-myc activation. The WS5 gene contains 11 exons, encoding a 733-amino acid protein with a transmembrane region and a polycystic kidney disease (PKD) domain. Near the transcriptional start site, the WS5 promoter contains a cluster of four binding sites for the Myc-Max complex and a binding site for transcription factor C/EBPalpha. Electrophoretic mobility shift assays and chromatin immunoprecipitation showed that Myc, Max and C/EBPalpha bind specifically to these sites. Functional promoter analyses revealed that both the Myc-binding site cluster and the C/EBPalpha-binding site are essential for strong transcriptional activation, and that Myc and C/EBPalpha synergistically activate the WS5 promoter. Ectopic expression of WS5 led to cell transformation documented by anchorage-independent growth. The human melanoma antigen Pmel17, a type I transmembrane glycoprotein, is the mammalian protein with the highest amino acid sequence identity (38%) to WS5. The Pmel17 gene is regulated by the MITF protein, a bHLHZip transcription factor with DNA binding specificities similar to those of Myc/Max. WS5 is also related to human glycoprotein GPNMB expressed in metastatic melanoma cells and implicated in the progression of brain and liver tumors.


Assuntos
Glicoproteínas/genética , Melanoma/genética , Proteínas de Membrana/genética , Proteínas Oncogênicas/genética , Proteínas Proto-Oncogênicas c-myc/fisiologia , Sequência de Aminoácidos , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Humanos , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Ligação Proteica , Proteínas Proto-Oncogênicas c-myc/metabolismo , Homologia de Sequência de Aminoácidos
7.
Bioresour Technol ; 99(18): 8578-84, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18508262

RESUMO

The aim of the present study was the characterization of soil samples of a closed unlined landfill located northwest of Thessaloniki, North Greece, in relation to heavy metals values. Samples were obtained by drilling in different depths (2.5-17.5m). Then they were analyzed by atomic absorption spectrophotometry for Cd, Cr, Cu, Ni, Pb and Zn investigation. The chemical analysis showed that the metal values varied over a wide range: from 0.50 to 18.75mg/kg for Cd, 3.88-171.88mg/kg for Cr, 8.13-356.25mg/kg for Cu, 5.63-63.75mg/kg for Ni, 2.50-92.50mg/kg for Pb and 6.38-343.75mg/kg for Zn. The highest values found in three of the six drillings, in depths over 2.5m. Although the area is heavily industrialized, the presented results indicated that local industries have not constituted an extensive metal pollution source for the site. Finally, after all necessary preparatory operations of site cleaning and flattening, surface planting selected and applied as a phytoremediation rehabilitation method of the site.


Assuntos
Metais Pesados/análise , Poluentes do Solo/análise , Solo/análise
8.
Waste Manag ; 28(8): 1441-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17869500

RESUMO

In the municipality of Thessaloniki in 2006 mercury-bearing dental wastes were not managed properly by 80% of dentists and metal-bearing waste was handled in accordance with internationally established best management practices by less than 50% of dentists. Those results were documented through a biennial field-based research study that took place in private dental units within the Thessaloniki Urban Area. For quantifying the waste produced, structured questionnaires were used and interviews with dentists were performed. In the present work, results of this survey are presented; critical parameters and factors affecting the quantity and quality of the dental waste stream are reported together with the analysis and classification of dominant conditions and needs of the dental sector in the waste management field.


Assuntos
Eliminação de Resíduos de Serviços de Saúde/métodos , Eliminação de Resíduos/métodos , Gerenciamento de Resíduos/métodos , Cidades , Coleta de Dados , Resíduos Odontológicos , Odontologia/métodos , Grécia , Humanos , Inquéritos e Questionários
9.
Oncogene ; 25(29): 4043-55, 2006 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-16491116

RESUMO

Avian fibroblasts transformed simultaneously by the v-myc and v-mil(raf) oncogenes of acute leukemia and carcinoma virus MH2 contain elevated levels of c-Fos and c-Jun, major components of the transcription factor complex AP-1. To define specific transcriptional targets in these cells, subtractive hybridization techniques were employed leading to the identification of strongly upregulated genes including OPN (osteopontin), 126MRP, and rac2. OPN is a cytokine and cell attachment protein which has been implicated in human tumor progression and metastasis, the calcium binding 126MRP protein is related to the human S100 protein family involved in invasive cell growth, and the Rac2 protein belongs to the Rho family of small GTPases regulating actin reorganization and cell migration. Promoter analysis indicated that OPN activation is mediated by a non-consensus AP-1 binding site located close to the transcription start site. Electrophoretic mobility shift assays, chromatin immunoprecipitation and transcriptional reporter gene analyses showed that c-Fos and c-Jun bind specifically to this site and that c-Fos efficiently transactivates the OPN promoter. High-level expression of OPN, 126MRP, or Rac2 proteins from a retroviral vector led to partial cell transformation, documented by morphological changes and anchorage-independent growth. The specific activation in v-myc/v-mil(raf)-transformed cells of target genes with intrinsic oncogenic potential may provide an explanation for the longstanding observation that concomitant expression of these oncogenes leads to strongly enhanced oncogenicity in vivo and in vitro compared to cell transformation by v-myc or v-mil(raf) alone.


Assuntos
Transformação Celular Neoplásica , Transformação Celular Viral , Fibroblastos/metabolismo , Regulação Neoplásica da Expressão Gênica , Genes myc , Metástase Neoplásica , Proteínas Oncogênicas v-raf/metabolismo , Fator de Transcrição AP-1/metabolismo , Alpharetrovirus/genética , Alpharetrovirus/metabolismo , Animais , Movimento Celular/genética , Transformação Celular Neoplásica/genética , Transformação Celular Viral/genética , Células Cultivadas , Embrião de Galinha , Galinhas , Coturnix , Fibroblastos/patologia , Genes jun/genética , Genes myc/genética , Humanos , Metástase Neoplásica/genética , Proteínas Oncogênicas v-raf/genética , Osteopontina , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , Sialoglicoproteínas/biossíntese , Sialoglicoproteínas/genética , Fator de Transcrição AP-1/genética , Regulação para Cima , Proteínas rac de Ligação ao GTP/genética , Proteínas rac de Ligação ao GTP/metabolismo , Proteína RAC2 de Ligação ao GTP
10.
Postgrad Med J ; 83(980): 379-83, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17551068

RESUMO

Spontaneous bacterial peritonitis (SBP) is the infection of ascitic fluid in the absence of any intra-abdominal, surgically treatable source of infection. Despite timely diagnosis and treatment its reported incidence in ascitic patients varies between 7-30%. Ascitic paracentesis remains the chief diagnostic procedure. Automated cell counters have the same diagnostic accuracy as the manual measurement of white cells. Lately, the use of leucocyte reagent strips (dipsticks) has emerged as a useful alternative. Examination of the fluid is not complete unless the sample is inoculated in blood culture bottles. Treatment is currently with third-generation cephalosporins or oral quinolones. Following a single episode of SBP patients should have long term antibiotic prophylaxis.


Assuntos
Infecções Bacterianas , Peritonite/microbiologia , Albuminas/uso terapêutico , Antibacterianos/uso terapêutico , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/etiologia , Infecções Bacterianas/terapia , Humanos , Peritonite/diagnóstico , Peritonite/etiologia , Peritonite/terapia
11.
Ann Hepatol ; 5(3): 170-1, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17060875

RESUMO

Chronic liver disease may involve the lung through abnormal communications between the portal and pulmonary veins or by changes in the lungs caused by similar biochemical abnormalities to those in liver parenchyma. Lymphocytic interstitial pneumonitis(LIP) is more common in women and is associated with autoimmune diseases. Chest x-ray findings include reticular or reticulonodular opacities while computed tomography (CT) usually shows subpleural fibrosis (predominately in basal areas), ground-glass attenuation, traction bronchiectases and pulmonary parenchymal cysts.


Assuntos
Hepatite Autoimune , Doenças Pulmonares Intersticiais , Pulmão/patologia , Linfócitos/imunologia , Adulto , Diagnóstico Diferencial , Feminino , Hepatite Autoimune/complicações , Hepatite Autoimune/imunologia , Hepatite Autoimune/patologia , Humanos , Doenças Pulmonares Intersticiais/etiologia , Doenças Pulmonares Intersticiais/imunologia , Doenças Pulmonares Intersticiais/patologia , Masculino
12.
Waste Manag ; 26(2): 110-22, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16310115

RESUMO

This paper presents the results from an analysis of municipal charges in Greece, as the fees paid by municipal waste producers to the municipal authorities are included in these charges and constitute a major part of them. The aim is to determine whether and how some of the demographic characteristics of a municipality influence the formulation of municipal waste charges and specifically the level of the charge. The study included 339 Hellenic municipalities, which comprised approximately 62% of the overall population in the country.


Assuntos
Eliminação de Resíduos/economia , Honorários e Preços , Grécia , Humanos , Densidade Demográfica , Características de Residência
13.
Reprod Fertil Dev ; 14(7-8): 427-31, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12617786

RESUMO

Ninety-two healthy Friesian cows were used to determine the concentration of calcium (Ca), zinc (Zn), magnesium (Mg), potassium (K) and sodium (Na) in bovine cervical mucus and to compare these concentrations in cervical mucus collected during spontaneous and induced oestrus. Cows were assigned to four groups: (1) no treatment (2) PRID for 12 days plus pregnant mare's serum gonadotrophin (PMSG; 1000 IU, i.m.) at the removal of the PRID (3) PGF(2alpha), two doses (6 mg, i.m.) 11 days apart, and (4) PRID for 7 days plus one dose of PGF(2alpha) (6 mg, i.m.) 24 h before removal of the PRID. The cows of the three induced-oestrus groups received two artificial inseminations (AI), whereas those in the spontaneous-oestrus group received only one. Cervical mucus samples were collected from all cows 5 to 30 min before the first AI. The results of this study can be summarized as follows: (1) viscosity was significantly lower (P<0.001) and crystallization was significantly (P<0.001) higher in the cervical mucus of cows in the spontaneous-oestrus group compared with cows in the induced-oestrus groups; (2) Na concentration was similar in all groups; (3) concentration of all the other elements in the spontaneous-oestrus group was significantly lower (P<0.05) than in the induced-oestrus groups; (4) there was significant positive correlation (P<0.001) between viscosity and all elements, and significant negative correlation (P<0.05-P<0.001) between crystallization and all elements.


Assuntos
Bovinos , Muco do Colo Uterino/química , Dinoprosta/administração & dosagem , Estro/efeitos dos fármacos , Progesterona/administração & dosagem , Oligoelementos/análise , Animais , Cálcio/análise , Cristalização , Feminino , Gonadotropinas Equinas/administração & dosagem , Inseminação Artificial/veterinária , Magnésio/análise , Potássio/análise , Sódio/análise , Viscosidade , Zinco/análise
14.
Vet Parasitol ; 95(1): 63-71, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11163699

RESUMO

In each of two experiments, the reproductive performance of ewes naturally infested with sarcoptic mange and of uninfested ewes was assessed in in-season natural breeding conditions (experiment I) or in out-of-season controlled breeding conditions (experiment II). A statistically significant difference was observed in the total lambs born per ewe (infested ewes, 1.2; controls, 1.6), in the liveborn lambs per ewe (infested ewes, 1.2; controls, 1.5) and in the lamb body weight per ewe (infested ewes, 3.33kg; controls, 4.53kg) under natural breeding conditions, as well as in the lamb body weight per ewe (infested ewes, 3.37kg; controls, 4.14kg) among ewes under controlled breeding conditions. No adverse effects were observed in the other reproductive indices, cycling rate, mating rate, return-to-oestrus rate, abortion rate, lambing rate and stillbirth rate. Sarcoptic mange was observed in the offspring of infested ewes after 30 days and in the offspring of uninfested controls 60 days after their birth.


Assuntos
Transmissão Vertical de Doenças Infecciosas/veterinária , Reprodução/fisiologia , Sarcoptes scabiei , Escabiose/veterinária , Doenças dos Ovinos/fisiopatologia , Doenças dos Ovinos/parasitologia , Ovinos/fisiologia , Animais , Animais Recém-Nascidos , Feminino , Grécia , Masculino , Gravidez , Escabiose/parasitologia , Escabiose/fisiopatologia , Escabiose/transmissão , Doenças dos Ovinos/transmissão , Estatísticas não Paramétricas
15.
Prev Vet Med ; 52(1): 43-52, 2001 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-11566377

RESUMO

In a field investigation of 47 flocks in south Greece, a clinical examination for fertility evaluation was done on 293 rams. In each ram, a general-health examination, examination of the genital organs and libido evaluation were carried out. In 143 (49%) of the 293 rams examined, at least one abnormality was recorded. The median within-flock prevalence risk (PR) of at least one abnormality was 58.0%, that of general-health abnormalities was 33%, that of genital abnormalities was 20% and that of libido abnormalities 14%. The principal abnormalities observed during the general-health examination were interdigital dermatitis, injuries of the sole, blowfly myiasis and brisket sores. The principal abnormalities observed during the examination of the genitalia were testicular hypoplasia, nodules into the testicular parenchyma, ulcerative lesions characteristic of orf in the prepuce and blowfly myiasis on the preputial orifice. The principal abnormalities observed during the evaluation of libido were incomplete erection and inability to mount the ewe. A statistically significant (P<0.05) positive association was recorded between: ram:ewe ratio and general-health abnormalities PR; general-health abnormalities PR and at least one abnormality PR; genital abnormalities PR and libido abnormalities PR; genital abnormalities PR and at least one abnormality PR; lambing percentage and total lambs born per ewe. A statistically significant (P<0.05) negative association was recorded between: ram age and general-health abnormalities PR; ram age and any abnormality PR; general-health abnormalities PR and lambing percentage.


Assuntos
Infertilidade Masculina/veterinária , Comportamento Sexual Animal , Doenças dos Ovinos/epidemiologia , Ovinos/fisiologia , Doenças Testiculares/veterinária , Animais , Coleta de Dados , Infertilidade Masculina/etiologia , Masculino , Prevalência , Fatores de Risco , Doenças dos Ovinos/patologia , Doenças Testiculares/complicações , Doenças Testiculares/epidemiologia
16.
Theriogenology ; 43(3): 605-13, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16727652

RESUMO

Ten mature lactating ewes of the Chios island breed 3.5 +/- 0.5 (Mean +/- SEM) yr of age and weighing 51.9 +/- 1.6 kg (Mean +/- SEM) were synchronized for estrus with intravaginal sponges impregnated with 60 mg 6a-methyl-17-acetoxyprogesterone (MPA). The sponges remained in place for 14 d and 500 IU im PMSG were injected at their withdrawal. Daily milk samples (3 d pretreatment, 14 d on treatment, and 5 d posttreatment) were collected and analyzed by a double antibody RIA procedure for MPA. The concentration of MPA (Mean +/- SEM) in the milk increased to 5.05 +/- 0.11 ng/ml within the first day of sponge insertion, then declined and remained at a constant level (3.08 +/- 0.26 ng/ml) while the sponge was in place, eventually dropping to the background level (0.65 +/- 0.05 ng/ml) 24 h following sponge withdrawal. The curve for the quantity of MPA excreted in the milk was identical to that of MPA concentrations, showing significant differences among experimental days and among ewes. Finally, there was a significant relationship between milk production and MPA excretion into the milk (r = +0.581( * *)). It is concluded that only a very small percentage (0.08 +/- 0.01) of MPA contained in each sponge is excreted into the milk from the moment of sponge insertion until 5 d after its removal.

17.
Theriogenology ; 36(4): 667-80, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16727036

RESUMO

The developmental characteristics in the volume of the ejaculate, motility (percentage of motile spermatozoa) and grade of motility (vitality), density, total number of spermatozoa per ejaculate and percentage of dead (stained) and of morphologically abnormal spermatozoa were studied in 14-to 46-week-old lambs of the Chios (n=10), Serres (=10) and Karaguniki (n=10) breeds, born in October 1984. The first appearance of spermatozoa in the ejaculate of the Chios, Serres and Karaguniki lambs occurred at 20.1+/-0.31 (x +/-SEM), 20.4+/-0.37 and 20.6+/-0.54 weeks of age, respectively, when the lambs had attained a body weight of 36.4+/-, 36.5+/-0.70 and 34.9+/-0.99 Kg, respectively. The volume of the ejaculate, the motility and the grade of motility of spermatozoa increased at a rapid rate up to the age of 32 weeks, when the relevant values were the same as those found in the adult animal. Density of the semen and the total number of spermatozoa per ejaculate increased at a slower rate up to the age of 46 weeks, while the percentages of dead (stained) and of morphologically abnormal spermatozoa decreased significantly between 20 and 32 weeks of age. It is concluded that the quality of the semen at the time when the first spermatozoa appear in the ejaculate is not satisfactory, but it improves in the course of the ensuing 2 to 3 months. The optimal age at which the lambs may be used for artificial insemination are 32, 36 and 34 weeks for the Chios, Serres and Karaguniki breeds, respectively.

18.
Theriogenology ; 53(6): 1285-93, 2000 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10832753

RESUMO

Twenty-three purebred Alpine (n=8), Saanen (n=7) and Damascus (n=8) goat bucks raised at the Institute of Reproduction and Artificial Insemination in Thessaloniki, Greece (40 degrees 37 minutes N, 22 degrees 58 minutes E and altitude 32 m above sea level), were used to study the effect of photoperiod on semen production. Samples were collected with an artificial vagina and examined immediately after collection. In spite of the variation in nearly all semen characteristics studied among the 3 breeds of bucks, there was significant seasonal variation in both semen quantity (volume, concentration and total number of spermatozoa per ejaculate) and quality (percentage of motile spermatozoa, percentage of abnormal spermatozoa and rate of progressive motility). The best semen was produced during the breeding season (late summer and autumn). However, the magnitude of these seasonal effects was not sufficient to prevent bucks from being used for breeding throughout the year. Nevertheless, individual differences in the semen quantity and quality among bucks within a breed make individual evaluation of semen necessary to select the most fertile males for breeding.


Assuntos
Cabras/fisiologia , Estações do Ano , Sêmen/fisiologia , Animais , Cruzamento , Fertilidade , Grécia , Masculino , Especificidade da Espécie , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides/anormalidades
19.
Theriogenology ; 48(6): 1049-59, 1997 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-16728194

RESUMO

A total of 4109 does of a local Greek breed (Capra prisca) were synchronized with intravaginal MPA-sponges and PMSG, and 24 bucks of Alpine (n = 8), Saanen (n = 8) and Damascus (n = 8) breeds were used for studying the fertility of nonfrozen and frozen-thawed semen during the nonbreeding season (June to August). Artificial insemination (AI) was performed once (50 to 55 h after sponge withdrawal) or twice (36 and 60 h after sponge withdrawals with fresh semen (collected during the nonbreeding season, stored at 16 degrees C and inseminated within 6 h) or frozen semen (prepared from the same bucks during the preceding breeding season). The induction of estrus was successful, varying between 91.0 and 95.0%. The form of semen (fresh or frozen-thawed used for inseminating the synchronized does affected their fertility: the overall kidding rate with fresh semen (65.5%) was higher (P < 0.05) than that with frozen-thawed semen (53.4%). The fertility level was also affected by the number of inseminations performed: the overall kidding rate was significantly higher (P < 0.001) in the does inseminated twice with fresh or frozen-thawed semen (70.4 and 59. 1%, respectively) than in those inseminated only once (48.9 and 44.9%, respectively). Finally, the breed of the buck used for preparing the fresh or the frozen-thawed semen affected the fertility level of the does. The kidding rate was higher in does inseminated with fresh semen prepared from bucks of the Damascus breed than from bucks of Saanen or Alpine breed. However, when frozen-thawed semen was used the kidding rate was lower in does inseminated with semen prepared from bucks of the Damascus breed than from bucks of the Alpine or Saanen breed. It is concluded that the fresh semen of Alpine, Saanen and Damascus breed bucks, born and raised under the climate conditions prevailing in Greece (34 degrees to 41 degrees N), can be used successfully during the nonbreeding season (June to August) for inseminating does.

20.
Theriogenology ; 35(4): 785-98, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16726948

RESUMO

The aim of the present study was to examine the effect of steroid-free bovine follicular fluid (bFF) on both ovulation and lambing rates. For this purpose, 30 adult ewes of the Karaguniki breed were randomly allocated to three treatment groups (A,B and C; n=10 ewes each) during the breeding season of 1988. The ewes in Group A received bFF (6 ml iv) twice daily during their luteal phase, starting on Day 5 and lasting until Day 9. The ewes in Group B received a mixture of bFF/arachid oil (3 ml sc, 2:1) on Days 3, 4, 5, 10 and 12 of the estrous cycle. The ewes in Group C (Controls) were treated subcutanecusly with a mixture of steroid-free bovine plasma and arachid oil (2:1) on the same days as the ewes in Group B. Plasma concentrations of progesterone showed that the luteal function during the treatment cycle was normal in all treated and control ewes. The ovulation and lambing rates, however, were greater in Group A (2.5 +/- 0.2 and 1.9 +/- 0.3, respectively) and in Group B (2.1 +/- 0.2 and 1.6 +/- 0.1, respectively) than in Group C (1.5 +/- 0.2 and 1.2 +/- 0.3, respectively). Precipitating antibodies were detected in the plasma of Group B ewes only.

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