Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 71
Filtrar
1.
Vet Ital ; 58(4)2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37303140

RESUMO

A voluntary bovine viral diarrhoea virus (BVDV) control programme, which later became a compulsory eradication programme, based on the Swedish model was introduced in Lower Austria in 1997. The persistently infected animals were detected by Ag-ELISA and all samples were re-tested by the improved single-tube RT-PCR, employing panpestivirus primers targeting the 5'-UTR of the virus genome. In 2010, the BVDV eradication programme, which became compulsory from 2004, reached the final stage with only five remaining infected herds in which BVDV was difficult to eradicate. To resolve the problem in those herds, a molecular epidemiology approach was used. No differences in the spectrum of BVDV-1 subgenotypes at the beginning and at the final stage of eradication programme were found. The genetic study revealed the importance of human risk factor when finishing an eradication programme. Molecular epidemiology was also used to analyse BVDV isolates associated with re-introductions to BVDV-free herds.


Assuntos
Vírus da Diarreia Viral Bovina , Animais , Humanos , Áustria , Vírus da Diarreia Viral Bovina/genética , Ensaio de Imunoadsorção Enzimática/veterinária , Genoma Viral , Técnicas Genéticas/veterinária
2.
Genetics ; 218(1)2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-33742653

RESUMO

Design and large-scale synthesis of DNA has been applied to the functional study of viral and microbial genomes. New and expanded technology development is required to unlock the transformative potential of such bottom-up approaches to the study of larger mammalian genomes. Two major challenges include assembling and delivering long DNA sequences. Here, we describe a workflow for de novo DNA assembly and delivery that enables functional evaluation of mammalian genes on the length scale of 100 kilobase pairs (kb). The DNA assembly step is supported by an integrated robotic workcell. We demonstrate assembly of the 101 kb human HPRT1 gene in yeast from 3 kb building blocks, precision delivery of the resulting construct to mouse embryonic stem cells, and subsequent expression of the human protein from its full-length human gene in mouse cells. This workflow provides a framework for mammalian genome writing. We envision utility in producing designer variants of human genes linked to disease and their delivery and functional analysis in cell culture or animal models.


Assuntos
Clonagem Molecular/métodos , Engenharia Genética/métodos , Animais , DNA/genética , Técnicas de Transferência de Genes/veterinária , Técnicas Genéticas/veterinária , Genoma/genética , Genômica/métodos , Humanos , Hipoxantina Fosforribosiltransferase/genética , Camundongos , Análise de Sequência de DNA/métodos , Fluxo de Trabalho
3.
J Vet Diagn Invest ; 32(5): 737-741, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32633638

RESUMO

High quantities of quality RNA are necessary for many veterinary laboratory tests. Several commercial kits are available for RNA isolation from human whole blood; their resultant RNA yield and purity have not been reported for canine whole blood, to our knowledge. We assessed the performance of 4 RNA extraction kits (RiboPure, TRIzol, RNeasy Protect animal blood, and QIAamp RNA blood mini). Whole blood from a healthy dog was stored in the manufacturer-recommended RNA stabilizing buffer as directed. RNA isolation, including DNase treatment, was performed using each kit's manufacturer's protocol. Resultant RNA yield and purity were evaluated using spectrophotometric absorbance, capillary electrophoresis and electropherogram analysis, and a reverse-transcription real-time PCR (RT-rtPCR) assay. The RNeasy Protect animal blood kit extracted the highest, and RiboPure the lowest, concentration of nucleic acid. RNA integrity numbers classified extracted RNA as good quality or better for all kits except RNeasy Protect. All kits had evidence of genomic DNA contamination as assessed by RT-rtPCR. Overall, QIAamp RNA blood mini kit and TRIzol optimized both RNA yield and purity from canine whole blood. These kits extracted high quantities of good quality RNA as evidenced by high RNA integrity numbers and minimal contamination with proteins and solvents.


Assuntos
Análise Química do Sangue/veterinária , Cães/sangue , Técnicas Genéticas/veterinária , RNA/isolamento & purificação , Animais , Análise Química do Sangue/instrumentação , Técnicas Genéticas/instrumentação , RNA/análise , Kit de Reagentes para Diagnóstico/veterinária
4.
Reprod Fertil Dev ; 32(10): 948-952, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32586425

RESUMO

Herein we report a simple method for assessing avian sperm DNA fragmentation (SDF) using the sperm chromatin dispersion test (SCDt). The presence of sperm DNA damage was confirmed indirectly by correlating results of the SCDt determined in three bird species with results of a corresponding neutral comet assay (r=0.99; P<0.005). Frozen-thawed spermatozoa of each species were also incubated at 37°C for 5h and the within- and between-species variation of SDF, as an indicator of sperm DNA longevity, examined. The dynamic assessment of SDF using the SCDt revealed species and individual bird (rooster and turkey) differences in sperm DNA longevity.


Assuntos
Galinhas/genética , Cromatina/química , Cacatuas/genética , Fragmentação do DNA , Espermatozoides/química , Perus/genética , Animais , Ensaio Cometa/veterinária , Técnicas Genéticas/veterinária , Masculino , Reprodutibilidade dos Testes
5.
Commun Biol ; 3(1): 84, 2020 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-32081985

RESUMO

Ancient remains found in permafrost represent a rare opportunity to study past ecosystems. Here, we present an exceptionally well-preserved ancient bird carcass found in the Siberian permafrost, along with a radiocarbon date and a reconstruction of its complete mitochondrial genome. The carcass was radiocarbon dated to approximately 44-49 ka BP, and was genetically identified as a female horned lark. This is a species that usually inhabits open habitat, such as the steppe environment that existed in Siberia at the time. This near-intact carcass highlights the potential of permafrost remains for evolutionary studies that combine both morphology and ancient nucleic acids.


Assuntos
Aves , Osso e Ossos/metabolismo , Fósseis , Técnicas Genéticas , Determinação da Idade pelo Esqueleto/métodos , Determinação da Idade pelo Esqueleto/veterinária , Animais , Aves/classificação , Aves/genética , Osso e Ossos/anatomia & histologia , Osso e Ossos/química , Ecossistema , Feminino , Fósseis/anatomia & histologia , Fósseis/patologia , Técnicas Genéticas/veterinária , Genética Populacional , Sedimentos Geológicos/análise , História Antiga , Masculino , Paleontologia , Pergelissolo , Filogenia , Datação Radiométrica , Análise para Determinação do Sexo/métodos , Análise para Determinação do Sexo/veterinária , Sibéria
6.
Acta Vet Scand ; 61(1): 57, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31796072

RESUMO

Non-infectious inflammatory (NII) central nervous system (CNS) conditions are primarily diagnosed by the demonstration of inflammatory changes in the cerebrospinal fluid (CSF). However, less-invasive methods and peripheral biomarkers are desired. Changes in circulating microRNA (miRNA), which are short non-coding regulatory RNAs, may serve as biomarkers of disease. The aim of this pilot study was to investigate selected miRNAs in serum and CSF, hypothesizing that the levels of specific miRNAs in serum correlate with their presence in CSF, and that changes in serum miRNAs levels may reflect CNS disease. We profiled serum and CSF samples using quantitative real-time PCR (qPCR) searching for selected and previously profiled miRNAs in serum (let-7a, let-7c, miR-15b, miR-16, miR-21, miR-23a, miR-24, miR-26a, miR-146a, miR-155, miR-181c and miR-221-3p) and in CSF (let-7c, miR-16, miR-21, miR-24, miR-146a, miR-155, miR-181c and miR-221-3p) from 13 dogs with NII CNS disease and six control dogs. We demonstrated the presence of several miRNAs in CSF (let-7c and miR-21 dominating) and serum (miR-23a and miR-21 dominating). However, we generally failed to reproduce consistent results in CSF samples due to several reasons: unacceptable PCR efficiency, a wide variation between cDNA replicates and/or no-amplification in qPCR suggesting very low levels of the investigated miRNAs in canine CSF. Serum samples performed better, and 10 miRNAs qPCR assays were qualified for analysis. We were nevertheless unable to detect a difference in the expression of miRNA levels between cases and controls. Moreover, we could not confirm the results of recent miRNA investigations of canine CNS diseases. We believe that these disagreements highlight the significant effect of methodological/analytical variation, rather than the incapacity of circulating miRNAs as biomarkers of CNS disease. A secondary aim was therefore to communicate methodological challenges in our study and to suggest recommendations for circulating miRNA profiling, including pre-, post- and analytical methods based on our experience, in order to reach reproducible and comparable results in veterinary miRNA research.


Assuntos
Doenças do Sistema Nervoso Central/veterinária , Doenças do Cão/etiologia , Técnicas Genéticas/veterinária , MicroRNAs/sangue , MicroRNAs/síntese química , Animais , Biomarcadores/sangue , Doenças do Sistema Nervoso Central/etiologia , Testes Diagnósticos de Rotina/veterinária , Cães , Feminino , Masculino , Projetos Piloto , Reação em Cadeia da Polimerase em Tempo Real/veterinária
7.
Reprod Fertil Dev ; 32(2): 50-55, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32188557

RESUMO

The Canadian dairy industry has been using invivo and invitro assisted reproductive technologies to produce embryos. Technological improvements have helped increase the number and quality of embryos produced, but genetic and genomic tools for improving these traits have yet to be assessed for the Canadian Holstein population. Genetic parameters and a genome-wide association study were performed in Canadian Holstein for the total number of embryos (NE) and the number of viable embryos (VE). Results showed potential for genetic selection for both NE and VE, with heritability estimates (± s.e.) of approximately 0.15±0.01. Genetic correlations between the number of embryos produced using different procedures (invivo and invitro) suggested that a similar number of embryos should be expected from a donor regardless of the procedure used. A region on chromosome 11 of the bovine genome was found to be significantly associated with the number of embryos, indicating a potential regulatory role of this region on embryo production. Overall, these findings are of interest for the Canadian dairy industry because they provide useful information for breeders that are interested in producing embryos from the elite donors in their herds or in the population using assisted reproductive technologies.


Assuntos
Cruzamento/métodos , Bovinos/embriologia , Indústria de Laticínios/métodos , Embrião de Mamíferos/citologia , Técnicas Genéticas/veterinária , Técnicas de Reprodução Assistida/veterinária , Animais , Bovinos/genética , Clonagem de Organismos/métodos , Clonagem de Organismos/veterinária , Indústria de Laticínios/tendências , Embrião de Mamíferos/fisiologia , Feminino , Estudo de Associação Genômica Ampla/veterinária , Genômica/métodos , Genômica/tendências , Seleção Genética
8.
Arch Anim Nutr ; 72(2): 85-99, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29381103

RESUMO

The objective of this study was to compare the automated ribosomal intergenic spacer analysis (ARISA) and the denaturing gradient gel electrophoresis (DGGE) techniques for analysing the effects of diet on diversity in bacterial pellets isolated from the liquid (liquid-associated bacteria (LAB)) and solid (solid-associated bacteria (SAB)) phase of the rumen. The four experimental diets contained forage to concentrate ratios of 70:30 or 30:70 and had either alfalfa hay or grass hay as forage. Four rumen-fistulated animals (two sheep and two goats) received the diets in a Latin square design. Bacterial pellets (LAB and SAB) were isolated at 2 h post-feeding for DNA extraction and analysed by ARISA and DGGE. The number of peaks in individual samples ranged from 48 to 99 for LAB and from 41 to 95 for SAB with ARISA, and values of DGGE-bands ranged from 27 to 50 for LAB and from 18 to 45 for SAB. The LAB samples from high concentrate-fed animals tended (p < 0.10) to show greater peak numbers and Shannon index values than those isolated from high forage-fed animals with ARISA, but no differences were identified with DGGE. The SAB samples from high concentrate-fed animals had lower (p < 0.05) peak numbers and Shannon index values than those from animals fed high-forage diets with ARISA, but only a trend was noticed for these parameters with DGGE (p < 0.10). The ARISA detected that animals fed alfalfa hay diets showed lower (p < 0.05) SAB diversity than those fed grass hay diets, but no differences were observed with DGGE. No effect of forage type on LAB diversity was detected by any technique. In this study, ARISA detected some changes in ruminal bacterial communities that were not detected by DGGE, and therefore ARISA was considered more appropriate for assessing bacterial diversity of ruminal bacterial pellets. The results highlight the impact of the fingerprinting technique used to draw conclusions on dietary factors affecting bacterial diversity in ruminal bacterial pellets.


Assuntos
Ciências da Nutrição Animal/métodos , Eletroforese em Gel de Gradiente Desnaturante/veterinária , Microbioma Gastrointestinal , Técnicas Genéticas/veterinária , Cabras/microbiologia , Ovinos/microbiologia , Ciências da Nutrição Animal/instrumentação , Animais , Fenômenos Fisiológicos Bacterianos , DNA Espaçador Ribossômico/análise , Eletroforese em Gel de Gradiente Desnaturante/métodos , Dieta/veterinária , Cabras/fisiologia , Rúmen/microbiologia , Ovinos/fisiologia
9.
Zebrafish ; 14(6): 586-588, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28767326

RESUMO

A bottleneck in CRISPR/Cas9 genome editing is variable efficiencies of in silico-designed gRNAs. We evaluated the sensitivity of the TIDE method (Tracking of Indels by DEcomposition) introduced by Brinkman et al. in 2014 for assessing the cutting efficiencies of gRNAs in zebrafish. We show that this simple method, which involves bulk polymerase chain reaction amplification and Sanger sequencing, is highly effective in tracking well-performing gRNAs in pools of genomic DNA derived from injected embryos. The method is equally effective for tracing INDELs in heterozygotes.


Assuntos
Técnicas Genéticas/veterinária , Mutação INDEL , RNA Guia de Cinetoplastídeos/genética , Peixe-Zebra/genética , Animais , Sistemas CRISPR-Cas , Edição de Genes , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de RNA/métodos
10.
J Dairy Sci ; 100(9): 7362-7367, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28711268

RESUMO

Excessive ambient temperature and humidity can impair milk production and fertility of dairy cows. Selection for heat-tolerant animals is one possible option to mitigate the effects of heat stress. To enable selection for this trait, we describe the development of a heat tolerance breeding value for Australian dairy cattle. We estimated the direct genomic values of decline in milk, fat, and protein yield per unit increase of temperature-humidity index (THI) using 46,726 single nucleotide polymorphisms and a reference population of 2,236 sires and 11,853 cows for Holsteins and 506 sires and 4,268 cows for Jerseys. This new direct genomic value is the Australian genomic breeding value for heat tolerance (HT ABVg). The components of the HT ABVg are the decline in milk, fat, and protein per unit increase in THI when THI increases above the threshold of 60. These components are weighted by their respective economic values, assumed to be equivalent to the weights applied to milk, fat, and protein yield in the Australian selection indices. Within each breed, the HT ABVg is then standardized to have a mean of 100 and standard deviation (SD) of 5, which is consistent with the presentation of breeding values for many other traits in Australia. The HT ABVg ranged from -4 to +3 SD in Holsteins and -3 to +4 SD in Jerseys. The mean reliabilities of HT ABVg among validation sires, calculated from the prediction error variance and additive genetic variance, were 38% in both breeds. The range in ABVg and their reliability suggests that HT can be improved using genomic selection. There has been a deterioration in the genetic trend of HT, and to moderate the decline it is suggested that the HT ABVg should be included in a multitrait economic index with other traits that contribute to farm profit.


Assuntos
Cruzamento , Termotolerância/genética , Animais , Austrália , Cruzamento/normas , Bovinos , Feminino , Técnicas Genéticas/veterinária , Umidade , Lactação , Masculino , Leite/metabolismo , Proteínas do Leite/biossíntese , Reprodutibilidade dos Testes , Temperatura , Termotolerância/fisiologia
11.
Pesqui. vet. bras ; 33(9): 1116-1120, set. 2013. tab
Artigo em Português | LILACS | ID: lil-694060

RESUMO

Mycoplasma haemofelis, 'Candidatus Mycoplasma haemominutum' e 'Candidatus Mycoplasma turicensis' são os agentes causadores da micoplasmose felina, que podem causar anemia aguda ou crônica. O objetivo deste trabalho foi determinar a ocorrência de hemoplasmas em gatos domésticos de Belém, Pará. Para isso, 201 gatos foram divididos em três grupos: Grupo A foi composto por 101 gatos de rua capturados pelo Centro de Controle de Zoonoses, o grupo B foi composto por 62 gatos domiciliados e saudáveis e o grupo C foi composto por 38 gatos domiciliados que apresentavam alguma afecção clínica. Foram coletadas amostras de sangue para a realização de Reação em Cadeia pela Polimerase (PCR) para detectar o DNA destes agentes, os quais foram sequenciados e alinhados. A análise estatística foi realizada para detectar a associação entre a infecção, o sexo dos animais e os grupos experimentais. O DNA de pelo menos uma das espécies de hemoplasmas pesquisados foi detectado em 19,9% (40/201) das amostras, sendo o DNA de 'Candidatus M. haemominutum' encontrado em 7,96% (16/201) das amostras, M. haemofelis em 1,49% (3/201) das amostras, enquanto que o DNA de 'Candidatus M. turicensis' foi detectado em 12,93% (26/201) das amostras. O DNA destes três agentes foi detectado em gatos dos grupos A e C, enquanto que no grupo B foi detectado apenas 'Candidatus M. turicensis' e 'Candidatus M. haemominutum' Foi detectada a influência do sexo sobre a infecção hemoplasmas apenas entre 'Candidatus M. haemominutum' e machos. Estes resultados mostraram que os hemoplasmas circulam entre os gatos domésticos em Belém e 'Candidatus M. turicensis' e 'Candidatus M. haemominutum' foram mais comuns do que M. haemofelis, especialmente em gatos vadios.


Mycoplasma haemofelis, 'Candidatus Mycoplasma haemominutum' and 'Candidatus Mycoplasma turicensis' are the causative agent of the feline mycoplasmosis, which could cause acute or chronic anemia. The aim of this work was to determine the occurrence of hemoplamas in domestic cats from Belém, Pará. To this, 201 cats were divided into three groups: Group A were composed by 101 stray cats captured by Zoonosis Control Center, group B were composed by 62 owners healthy cats and group C were composed by 38 owners cats that were suffering by some medical condition. Blood samples were collected to perform Polymerase Chain Reaction (PCR) to detect the DNA of these agents, which were sequenced and aligned. Statistical analysis was performed to detect association between the infection, the sex of the animals and experimental groups. The DNA of at least one of the hemoplasmas studied were detected in 19,9% (40/201) of the samples, being the DNA of 'Candidatus M. haemominutum' was found in 7.96% (16/201) of samples, M. haemofelis in 1.49% (3/201) of samples, while 'Candidatus M. turicensis' in 12.93% (26/201) of the samples. The DNA of these three agents was detected in cats from groups A and C, while in Group B was detected only 'Candidatus M. turicensis' and 'Candidatus M. haemominutum'. The influence of sex on hemoplasma infection was detected only between 'Candidatus M. haemominutum' and males. These findings showed that hemoplasma circulate among domestic cats in Belém, and 'Candidatus M. turicensis' and 'Candidatus M. haemominutum' were more common than M. haemofelis, especially in stray cats.


Assuntos
Animais , Gatos , Doenças do Gato/parasitologia , Infecções por Mycoplasma/veterinária , Mapeamento Cromossômico/veterinária , Reação em Cadeia da Polimerase/veterinária , Técnicas Genéticas/veterinária
13.
Vet Microbiol ; 163(3-4): 392-4, 2013 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-23395292

RESUMO

In many infection studies and approaches in breeding research it is of high importance to know the genetic predisposition of pigs for the susceptibility to the Escherichia coli (E. coli). Therefore, we developed a gene test to determine the status of the F18 receptor, as indicated by the FUT1 gene. A SNP in the FUT1 gene was first described by Vogeli et al. (1996) and a gene test was patented by Meijerink et al. (1997). Up until now, the gene test of Meijerink has been used in research. However, faster and cheaper genotyping techniques are now available, which led us to develop an easily applicable, fast and cost effective genetic test to determine the status of the F18 receptor. To check the accuracy of the new test, we genotyped 32 pigs with the established test as well as with our new test. All in all, we genotyped 430 German Landrace pigs. The test was successful. We suggest this allele specific test as a new standard genetic tool to determine the ETEC F18 receptor status in pigs.


Assuntos
Infecções por Escherichia coli/genética , Fucosiltransferases/genética , Predisposição Genética para Doença , Técnicas Genéticas/veterinária , Doenças dos Suínos/genética , Suínos/genética , Animais , Cruzamento , Escherichia coli Enterotoxigênica , Escherichia coli , Proteínas de Escherichia coli , Técnicas Genéticas/economia , Técnicas Genéticas/normas , Genótipo , Polimorfismo de Nucleotídeo Único/genética
14.
Arq. bras. med. vet. zootec ; 64(4): 991-1000, Aug. 2012. ilus, tab
Artigo em Português | LILACS | ID: lil-647702

RESUMO

Avaliou-se a sensibilidade dos valores genéticos do peso de codornas de corte, mensurados ao 21º e 35º dias de idade, a dietas contendo diferentes níveis de proteína bruta. Observações obtidas de animais provenientes de duas linhagens (EV1 e EV2) foram utilizadas no ajuste de modelos de regressão aleatória, considerando-se heterogeneidade de variância residual. Os coeficientes de regressão aleatória do intercepto (b0) e linear (b1) apresentaram correlação positiva entre si em todas as análises, porém a linhagem EV2 apresentou maior magnitude dos valores deste parâmetro para ambas as idades. Houve heterogeneidade de variância genética aditiva e alteração na herdabilidade com a mudança no nível proteico da dieta para ambos os grupos genéticos e em todas as idades avaliadas. As normas de reação do grupo EV1 indicam presença de interação entre genótipo e ambiente (G x E) em ambas as idades, com alteração na ordem dos efeitos genéticos de peso em função do nível proteico da dieta. Modificação da dispersão dos valores genéticos em função do nível de proteína indica presença de G x E na linhagem EV2. Portanto, a avaliação genética de codornas de corte sob dietas contendo determinado nível de proteína bruta não permite a predição de valores genéticos para outros níveis proteicos da dieta.


The sensitivity of genetic values for body weight of meat type quails predicted at 21 and 35 days of age under diets with different crude protein levels was evaluated. Data from subjects belonging to two strains (EV1 and EV2) were used to fit a random regression model under heterogeneity of residual variance assumption. The random regression coefficients for intercept (bo) and slope (b1) were positively correlated in all analyses results, but the correlation was higher in the EV2 data analyses for both ages. Results indicated that additive genetic variance and heritability change as a function of the environment gradient for both genetic strains and ages. The reaction norms for EV1 strain suggest there is genotype by environment interaction (G x E) for both ages as there were remarkable changes in the ranking of body weight breeding values for different crude protein levels. Furthermore, changes in the magnitude of the genetic effects dispersion as a function of protein level of diet indicates there is G x E in EV1 and EV2 strains. Therefore, the prediction of breeding values for body weight of quails under a specific level of crude protein in the diet does not hold for different environments regarding the level of this nutrient.


Assuntos
Animais , Coturnix/crescimento & desenvolvimento , Coturnix/metabolismo , Análise de Regressão , Técnicas Genéticas/veterinária
16.
Reprod Domest Anim ; 47(5): 865-71, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22128751

RESUMO

Embryo biotechnology has become one of the prominent high businesses worldwide. This technology has evolved through three major changes, that is, traditional embryo transfer (in vivo embryo production by donor superovulation), in vitro embryo production by ovum pick up with in vitro fertilization and notably current cloning technique by somatic cell nuclear transfer and transgenic animal production. Embryo biotechnology has widely been used in dairy and beef cattle industry and commercial bovine embryo transfer has become a large international business. Currently, many developed biotechnologies during the period from early oocyte stage to pre-implantation embryos can be used to create new animal breeds and accelerate genetic progression. Based on recent advances in embryo biotechnologies and authors current studies, this review will focus on a description of the application of this technology to beef cattle improvement and discuss how to use this technology to accelerate beef cattle breeding and production. The main topics of this presentation include the following: (i) how to increase calf production numbers from gametes including sperm and oocyte; (ii) multiple ovulation and embryo transfer breeding schemes; (iii) in vitro fertilization and intracytoplasm sperm injection in bovine; (iv) pronuclear development and transgenic animals; (v) sex selection from sperm and embryos; (vi) cloning and androgenesis; (vii) blastocyst development and embryonic stem cells; (viii) preservation of beef cattle genetic resources; and (ix) conclusions.


Assuntos
Bovinos , Técnicas Genéticas/veterinária , Carne , Técnicas de Reprodução Assistida/veterinária , Animais , Animais Geneticamente Modificados , Cruzamento/métodos , Bovinos/embriologia , Bovinos/genética , Bovinos/fisiologia , Clonagem de Organismos , Conservação dos Recursos Naturais , Transferência Embrionária/veterinária , Células-Tronco Embrionárias , Feminino , Fertilização In Vitro/veterinária , Masculino , Técnicas de Transferência Nuclear/veterinária , Pré-Seleção do Sexo/veterinária , Superovulação
17.
J Dairy Sci ; 94(7): 3642-50, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21700054

RESUMO

Genomic selection has been widely implemented in national and international genetic evaluation in the dairy cattle industry, because of its potential advantages over traditional selection methods and the availability of commercial high-density (HD) single nucleotide polymorphism (SNP) panels. However, this method may not be cost-effective for cow selection and for other livestock species, because the cost of HD SNP panels is still relatively high. One possible solution that can enable other species to benefit from this promising method is genomic selection with low-density (LD) SNP panels. In this simulation study, LD SNP panels designed with different strategies and different SNP densities were compared. The effects of number of quantitative trait loci, heritability, and effective population size were evaluated in the framework of genomic selection with LD SNP panels. Methodologies of Bayesian variable selection; BLUP with a trait-specific, marker-derived relationship matrix; and BLUP with a realized relationship matrix were employed to predict genomic estimated breeding values with both HD and LD SNP panels. Up to 95% of accuracy obtained by using an HD panel can be obtained by using only a small proportion of markers. The LD panel with markers selected on the basis of their effects always performs better than the LD panel with evenly spaced markers. Both the genetic architecture of the trait and the effective population size have a significant effect on the performance of the LD panels. We concluded that, to implement genomic selection with LD panels, a training population of sufficient size and genotyped with an HD panel is necessary. The trade-off between the LD panels with evenly spaced markers and selected markers must be considered, which depends on the number of target traits in a breeding program and the genetic architecture of these traits. Genomic selection with LD panels could be feasible and cost-effective, though before implementation, a further detailed genetic and economic analysis is recommended.


Assuntos
Cruzamento/métodos , Bovinos/genética , Técnicas Genéticas/veterinária , Genoma , Polimorfismo de Nucleotídeo Único/genética , Característica Quantitativa Herdável , Seleção Genética , Animais , Teorema de Bayes , Feminino , Marcadores Genéticos , Masculino , Reprodutibilidade dos Testes
18.
J Dairy Sci ; 94(7): 3679-86, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21700057

RESUMO

The purpose of this study was to investigate the imputation error and loss of reliability of direct genomic values (DGV) or genomically enhanced breeding values (GEBV) when using genotypes imputed from a 3,000-marker single nucleotide polymorphism (SNP) panel to a 50,000-marker SNP panel. Data consisted of genotypes of 15,966 European Holstein bulls from the combined EuroGenomics reference population. Genotypes with the low-density chip were created by erasing markers from 50,000-marker data. The studies were performed in the Nordic countries (Denmark, Finland, and Sweden) using a BLUP model for prediction of DGV and in France using a genomic marker-assisted selection approach for prediction of GEBV. Imputation in both studies was done using a combination of the DAGPHASE 1.1 and Beagle 2.1.3 software. Traits considered were protein yield, fertility, somatic cell count, and udder depth. Imputation of missing markers and prediction of breeding values were performed using 2 different reference populations in each country: either a national reference population or a combined EuroGenomics reference population. Validation for accuracy of imputation and genomic prediction was done based on national test data. Mean imputation error rates when using national reference animals was 5.5 and 3.9% in the Nordic countries and France, respectively, whereas imputation based on the EuroGenomics reference data set gave mean error rates of 4.0 and 2.1%, respectively. Prediction of GEBV based on genotypes imputed with a national reference data set gave an absolute loss of 0.05 in mean reliability of GEBV in the French study, whereas a loss of 0.03 was obtained for reliability of DGV in the Nordic study. When genotypes were imputed using the EuroGenomics reference, a loss of 0.02 in mean reliability of GEBV was detected in the French study, and a loss of 0.06 was observed for the mean reliability of DGV in the Nordic study. Consequently, the reliability of DGV using the imputed SNP data was 0.38 based on national reference data, and 0.48 based on EuroGenomics reference data in the Nordic validation, and the reliability of GEBV using the imputed SNP data was 0.41 based on national reference data, and 0.44 based on EuroGenomics reference data in the French validation.


Assuntos
Cruzamento/métodos , Bovinos/genética , Técnicas Genéticas/veterinária , Genoma , Polimorfismo de Nucleotídeo Único/genética , Característica Quantitativa Herdável , Seleção Genética , Animais , Cruzamento/economia , Marcadores Genéticos , Reprodutibilidade dos Testes
19.
Meat Sci ; 86(1): 129-37, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20510526

RESUMO

Ongoing meat and food industry consolidation has resulted in the creation of larger and more complex, vertically integrated and/or coordinated food production systems. These systems have also been focused on development of differentiated 'Value Chains' as a departure from the traditional commodity oriented 'Supply Chains'. The main goal of value chains is to achieve sustainable competitiveness through focusing resources on efficiently producing goods that offer superior consumer-recognized value. A closely-aligned value chain often contains vertically and horizontally linked players such as genetics and genetic improvement program(s), farmer(s), processor(s), distributor(s), and retailer(s). In this paper we postulate that the underlying foundation of the success of meat value chain accomplishments has been through substantial development of animal genetic technologies enabling sustainable production of animal protein-based consumer products of desirable quantity and quality. It is plausible to assume that further advancement in genomic selection and eventually proteomics will enable implementation of more complex genetic improvement programs leading to further development of differentiated meat value chains focused on ever changing consumer needs.


Assuntos
Animais Domésticos/genética , Comportamento do Consumidor/economia , Tecnologia de Alimentos , Técnicas Genéticas/veterinária , Carne/economia , Criação de Animais Domésticos/métodos , Animais , Marcadores Genéticos , Humanos , Controle de Qualidade
20.
Anim Genet ; 41(6): 662-5, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20394604

RESUMO

The camel racing industry would have added value in being able to assign parentage with high certainty. This study was aimed at assessing and applying microsatellite multiplexes to construct a parentage testing system for camels. An efficient system of 17 loci from 700 camel samples was used to construct a database of unrelated adults. Based on this, we estimated measures of polymorphism among the markers. In three multiplex reactions, we detected a total of 224 alleles, with 5­23 alleles/locus (mean = 13.18 ± 6.95 SD) and an average heterozygosity (HE) of 0.54 (range 0.032­0.905). The total parentage exclusion probability was 0.99999 for excluding a candidate parent from parentage of an arbitrary offspring, given only the genotype of the offspring, and 0.9999 for excluding a candidate parent from parentage of an arbitrary offspring, given the genotype of the offspring and the other parent. We used 15 juveniles for parentage testing, as well as 17 sires (bull camels) and 21 dams (cows). In the case of parentage assignment, the microsatellite panel assigned all 15 offspring parentage with high confidence. Overall, these findings offer a set of microsatellite markers that are easy, simple and highly informative for parentage testing in camels.


Assuntos
Camelus/genética , Impressões Digitais de DNA/métodos , Impressões Digitais de DNA/veterinária , Repetições de Microssatélites/genética , Alelos , Animais , DNA/química , DNA/genética , Feminino , Loci Gênicos/genética , Técnicas Genéticas/veterinária , Genótipo , Heterozigoto , Masculino , Linhagem , Reação em Cadeia da Polimerase/veterinária , Polimorfismo Genético
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA