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1.
Genetic control of immune responsiveness: a review of its use as a tool for selection for disease resistance 总被引：4，自引：0，他引：4
Disease resistance and immune responsiveness have been traits generally ignored by animal breeders. Recent advances in immunology and molecular biology have opened new avenues towards our understanding of genetic control of these traits. The major histocompatibility gene complex (MHC) appears to play a central role in all immune functions and disease resistance. The need to understand the relationship between immune responsiveness, disease resistance and production traits is discussed in this review. Antagonistic relationships might prevent simultaneous improvement of all of these traits by conventional breeding methods. It is suggested that genetic engineering methods may allow the simultaneous improvement of disease resistance and production traits in domestic animals. Genes of the MHC will be especially good candidates for genetic engineering experiments to improve domestic species. 相似文献
2.
Laible G 《Comparative immunology, microbiology and infectious diseases》2009,32(2):123-137
Transgenic technology allows for the stable introduction of exogenous genetic information into livestock genomes. With its ability to enhance existing or introduce entirely novel characteristics at unprecedented magnitude and speed this emerging technology is expected to have a profound impact on the genetic improvement of livestock in the future. The continual advances in animal genomics towards the identification of genes that influence livestock production traits and impact on human health will increase its ability and versatility for the purposeful modification of livestock animals to enhance their welfare, produce superior quality food and biomedical products and reduce the environmental impact of farming. In contrast to biomedicine, which has so far been the main driver for this technology platform, the potential opportunities for animal agriculture are more challenging because of the greater demands on cost, efficiency, consumer acceptance and relative value of the product. While various transgenic concepts for the genetic improvement of livestock animals for agriculture are being evaluated the integration of this technology into practical farming systems remains some distance in the future. 相似文献
3.
4.
Reiner G 《DTW. Deutsche tier?rztliche Wochenschrift》2008,115(7):252-259
Genetic components of disease resistance have been described in most of important diseases in human as well as in laboratory and livestock animals. However the basic mechanisms have been established in a few examples only. The reasons herefore are the mostly polygenic inheritance of disease resistance traits, the missing of suitable animal models and the dominance of environmental effects like infection pressure, immune status, and stressors, limiting the view on responsible gene variants. Ethical and practical aspects may further hinder research on disease resistance in certain species. Livestock animals play a crucial role in disease resistance research, because of distinct genetic diversity within and between breeds, because of an often distinct metabolic congruency with humans, and aiming towards the improvement of hygiene and economy of production and animal welfare. The following sections will review disease resistance in livestock animals and their practical implications, completed by examples of our own research activities. 相似文献
5.
Notter DR 《Journal of animal science》1999,77(1):61-69
Farm animal genetic diversity is required to meet current production needs in various environments, to allow sustained genetic improvement, and to facilitate rapid adaptation to changing breeding objectives. Production efficiency in pastoral species is closely tied to the use of diverse genetic types, but greater genetic uniformity has evolved in intensively raised species. In poultry, breeding decisions are directed by a few multinational companies and involve intense selection, the use of distinct production lines, and very large populations. In dairy cattle, the Holstein breed dominates production. Intensive sire selection is leading to relatively rapid inbreeding rates and raises questions about long-term effects of genetic drift. Key questions in management of farm animal genetic diversity involve the distribution of potentially useful quantitative trait locus alleles among global livestock breeds. Experiments with tomato, maize, and mice suggest that favorable alleles can exist in otherwise lowly productive stocks; this cryptic variation may potentially contribute to future selection response. Genetic improvement under relatively intense unidirectional selection may involve both increases in the frequency of favorable additive alleles as well as the progressive breakdown of homeostatic regulatory mechanisms established under the stabilizing selection that is characteristic of natural populations. Recombination among closely linked regulatory loci and new, potentially favorable mutations are possible sources of long-term genetic variation. A greater understanding of the potential that these alternative mechanisms have for supporting long-term genetic improvement and of genetic relationships among global livestock populations are priorities for managing farm animal genetic diversity. 相似文献
6.
Anna Giannina Perugini Maria Rosaria Carullo Assunta Esposito Vincenzo Caligiuri Federico Capuano Giorgio Galiero Giuseppe Iovane 《Veterinary research communications》2010,34(4):387-392
In the last two decades, the emergence and spread of antimicrobial-resistant pathogens, among them Salmonella, has become
a serious health hazard worldwide, and specifically the high incidence of multidrug resistance has been encountered widely
in many European countries. This study examines the antimicrobial supsceptibility of Salmonella enterica strains Typhimurium
and Enteritidis isolated in Campania and Calabria region (Southern Italy) from animal and food of animal origin. The relationship
of antibiotic resistance phenotype and the presence of some resistance genes has been also investigated. As espected, our
results showes that resistance to ampicillin, chloramphenicol, streptomycin, sulphonamides and tetracycline is common, although
resistance to other antibiotics (i.e.:nalidixic acid) and other resistance patterns occur. The genetic resistant patterns
have been partially described for this food-borne pathogen but efforts are needed to realize the complete characterization
of antimicrobial resistance genes. 相似文献
7.
Lucy MC 《New Zealand veterinary journal》2005,53(6):406-415
Dairy cattle have traditionally been selected for their ability to produce milk and milk components. The traditional single-minded approach to selection of dairy cattle has now changed and secondary traits are being included in selection indices by decreasing the emphasis on production. Greater emphasis on non-production traits reflects the industry's desire for functional dairy cattle. Six broad categories of non-lactational traits are discussed in this review. They are: type; growth, body size and composition; efficiency of feed utilisation; disease resistance, e.g. udder health as measured by somatic cell score; reproduction; and management. Most of these traits can be found within selection indices worldwide, although relative emphasis varies. The non-lactational traits mentioned above are quantitative, meaning that the phenotype in the whole animal represents the sum of lesser traits that cannot be easily measured. The physiological mechanisms that underlie quantitative traits are extremely complex. Genetic selection can be applied to quantitative traits but it is difficult to link successful genetic selection with the underlying physiological mechanisms. The importance that the bovine genome sequence will play in the future of the genetics of dairy cattle cannot be understated. Completing the bovine genome sequence is the first step towards modernising our approach to the genetics of dairy cattle. Finding genes in the genome is difficult and scanning billions of base pairs of DNA is an imperfect task. The function of most genes is either unknown or incompletely understood. Combining all of the information into a useable format is known as bioinformatics. At the present time, our capacity to generate information is great but our capacity to understand the information is small. The important information resides within subtle changes in gene expression and within the cumulative effect that these have. Traditional methods of genetic selection in dairy cattle will be used for the foreseeable future. Most non-lactational traits are heritable and will be included in selection indices if the traits have value. The long-term prognosis for genome science is good but advances will take time. Genetic selection in the genome era will be different because DNA sequence analysis may replace traditional methods of genetic selection. 相似文献
8.
MC Lucy 《New Zealand veterinary journal》2013,61(6):406-415
Dairy cattle have traditionally been selected for their ability to produce milk and milk components. The traditional single-minded approach to selection of dairy cattle has now changed and secondary traits are being included in selection indices by decreasing the emphasis on production. Greater emphasis on non-production traits reflects the industry's desire for functional dairy cattle. Six broad categories of non-lactational traits are discussed in this review. They are: type; growth, body size and composition; efficiency of feed utilisation; disease resistance, e.g. udder health as measured by somatic cell score; reproduction; and management. Most of these traits can be found within selection indices worldwide, although relative emphasis varies. The non-lactational traits mentioned above are quantitative, meaning that the phenotype in the whole animal represents the sum of lesser traits that cannot be easily measured. The physiological mechanisms that underlie quantitative traits are extremely complex. Genetic selection can be applied to quantitative traits but it is difficult to link successful genetic selection with the underlying physiological mechanisms. The importance that the bovine genome sequence will play in the future of the genetics of dairy cattle cannot be understated. Completing the bovine genome sequence is the first step towards modernising our approach to the genetics of dairy cattle. Finding genes in the genome is difficult and scanning billions of base pairs of DNA is an imperfect task. The function of most genes is either unknown or incompletely understood. Combining all of the information into a useable format is known as bioinformatics. At the present time, our capacity to generate information is great but our capacity to understand the information is small. The important information resides within subtle changes in gene expression and within the cumulative effect that these have. Traditional methods of genetic selection in dairy cattle will be used for the foreseeable future. Most non-lactational traits are heritable and will be included in selection indices if the traits have value. The long-term prognosis for genome science is good but advances will take time. Genetic selection in the genome era will be different because DNA sequence analysis may replace traditional methods of genetic selection. 相似文献
9.
Research opportunities in the field of animal genetic resources 总被引：1，自引：0，他引：1
Animal genetic resources are those animal species that are used, or may be used, for the production of food and agriculture, and the populations within each of them. The working unit of a database for farm animal genetic resources is the breed, a term taken in its widest possible sense to mean a population within the species, possessing a number of particular traits that permit the grouping of these animals under a common label and are associated to geographical areas and human groups. Research opportunities cover a wide range of thematic areas. The biggest gap in knowledge is animal breeding for local populations in harsh environments. There is also a lack of research in functional genetics and genomics of adaptation and disease resistance traits. By comparison, breed characterization, in particular molecular characterization, has been a more popular research subject. The same can be said for conservation, although some fundamental questions on genetic diversity and risk of its loss are still unanswered. Research is required to understand the socio-economic, infrastructural, technical and formal constraints that limit the operation of sustainable conservation programs in less developed countries. Information systems on animal genetic resources need input from research and data capture networks, in order to achieve a reasonable degree of completeness. Economic analysis and issues related to gene flow and access and benefit sharing should also profit from more research. 相似文献
10.
Disease is a major issue in animal production systems and society demands that the use of medicines and vaccines be reduced. This review describes the breeding approaches that could be used to improve disease resistance and focuses especially on their application to pigs. Disease reduction by genetic means has certain advantages through cumulative and permanent effects, and direct and indirect selection methods are available. Direct selection for disease incidence requires, besides a unique pig identification and disease registration system, challenge routines that are inconvenient in intensive pig production. Indirect selection for the expression of immune capacity may be an alternative but requires detailed knowledge of the different components of the immune system. There is ample opportunity for genetic improvement of the immune capacity because immune traits show substantial genetic variation between pigs. We therefore conclude that indirect selection via immune traits is very interesting, also for practical implementation, and that there is an urgent need for knowledge, within lines, about the genetic relationships between immune capacity traits and resistance to specific diseases or to disease incidence in general. Furthermore, knowledge about the relationship between immune system traits and production traits is needed as well as knowledge about the effect of selection on the epidemiology of disease at a farm/population level and on the host-pathogen interaction and coevolution. 相似文献
11.
披碱草属Elymus植物是小麦Triticum nestizum、大麦Hordeum vulgare的近缘属,同时蕴藏着丰富的优良基因,是改良小麦、大麦和黑麦Sacale cereale品种的优良基因资源。披碱草属植物也是草原和草甸的重要组成成分,具有极高的饲用价值和重要的水土保持功能,但国内在披碱草属植物资源和利用方面的研究与我国具有丰富的资源极不相称。现从国内外对披碱草属植物种间杂交利用方面进行论述,为充分开发利用我国丰富的披碱草属植物资源进行种质创新提供有价值的信息。 相似文献
12.
M. Martinez J. Blondeau C. E. Cerniglia J. Fink‐Gremmels S. Guenther R. P. Hunter X.‐Z. Li M. Papich P. Silley S. Soback P.‐L. Toutain Q. Zhang 《Journal of veterinary pharmacology and therapeutics》2014,37(1):e1-e16
Antimicrobial resistance is a global challenge that impacts both human and veterinary health care. The resilience of microbes is reflected in their ability to adapt and survive in spite of our best efforts to constrain their infectious capabilities. As science advances, many of the mechanisms for microbial survival and resistance element transfer have been identified. During the 2012 meeting of Antimicrobial Agents in Veterinary Medicine (AAVM), experts provided insights on such issues as use vs. resistance, the available tools for supporting appropriate drug use, the importance of meeting the therapeutic needs within the domestic animal health care, and the requirements associated with food safety and food security. This report aims to provide a summary of the presentations and discussions occurring during the 2012 AAVM with the goal of stimulating future discussions and enhancing the opportunity to establish creative and sustainable solutions that will guarantee the availability of an effective therapeutic arsenal for veterinary species. 相似文献
13.
Baiting and supplemental feeding of wildlife are widespread, yet highly controversial management practices, with important implications for ecosystems, livestock production, and potentially human health. An often underappreciated threat of such feeding practices is the potential to facilitate intra- and inter-specific disease transmission. We provide a comprehensive review of the scientific evidence of baiting and supplemental feeding on disease transmission risk in wildlife, with an emphasis on large herbivores in North America. While the objectives of supplemental feeding and baiting typically differ, the effects on disease transmission of these practices are largely the same. Both feeding and baiting provide wildlife with natural or non-natural food at specific locations in the environment, which can result in large congregations of individuals and species in a small area and increased local densities. Feeding can lead to increased potential for disease transmission either directly (via direct animal contact) or indirectly (via feed functioning as a fomite, spreading disease into the adjacent environment and to other animals). We identified numerous diseases that currently pose a significant concern to the health of individuals and species of large wild mammals across North America, the spread of which are either clearly facilitated or most likely facilitated by the application of supplemental feeding or baiting. Wildlife diseases also have important threats to human and livestock health. Although the risk of intra- and inter-species disease transmission likely increases when animals concentrate at feeding stations, only in a few cases was disease prevalence and transmission measured and compared between populations. Mostly these were experimental situations under controlled conditions, limiting direct scientific evidence that feeding practices exacerbates disease occurrence, exposure, transmission, and spread in the environment. Vaccination programs utilizing baits have received variable levels of success. Although important gaps in the scientific literature exist, current information is sufficient to conclude that providing food to wildlife through supplemental feeding or baiting has great potential to negatively impact species health and represents a non-natural arena for disease transmission and preservation. Ultimately, this undermines the initial purpose of feeding practices and represents a serious risk to the maintenance of biodiversity, ecosystem functioning, human health, and livestock production. Managers should consider disease transmission as a real and serious concern in their decision to implement or eliminate feeding programs. Disease surveillance should be a crucial element within the long-term monitoring of any feeding program in combination with other available preventive measures to limit disease transmission and spread. 相似文献
14.
微生物耐药是威胁人类健康、动物保健和食品安全的重大问题。为减少耐药性及动物源食品的药物残留,迫切需要探索预防和治疗疾病的替代机制,其中之一便是激活先天免疫系统对病原体攻击产生强而持久的非特异性免疫应答,这一过程称为训练免疫,即先天免疫记忆。愈来愈多的研究表明,天然免疫细胞甚至组织驻留干细胞对某些感染和疫苗接种具有保护免受再感染的免疫记忆功能,即先天免疫系统也表现出适应性免疫特征。在兽医研究领域,通过改善先天免疫系统提高家禽抗病能力的概念并不新颖,但极少有可用的、有目的的针对训练免疫的应用研究。通过训练免疫途径增强动物免疫力是一个值得关注的崭新领域,将为设计新型广谱疫苗和寻找新的药物靶点开辟新的途径。笔者综述了训练免疫领域的最新进展,阐述了家禽训练免疫调控及未来研究方向。 相似文献
15.
VN Meyers-Wallen 《Reproduction in domestic animals》2003,38(1):73-76
There is an ongoing revolution in medicine that is changing the way that veterinarians will be counselling clients regarding inherited disorders. Clinical applications will emerge rapidly in veterinary medicine as we obtain new information from canine and comparative genome projects ( Meyers‐Wallen 2001 : Relevance of the canine genome project to veterinary medical practice. International Veterinary Information Service, New York). The canine genome project is described by three events: mapping markers on canine chromosomes, mapping gene locations on canine chromosomes ( Breen et al. 2001 : Genome Res. 11, 1784–1795), and obtaining the nucleotide sequence of the entire canine genome. Information from such research has provided a few DNA tests for single gene mutations [ Aguirre 2000 : DNA testing for inherited canine diseases. In: Bonagura, J (ed), Current Veterinary Therapy XIII. Philadelphia WB Saunders Co, 909–913]. Eventually it will lead to testing of thousands of genes at a time and production of DNA profiles on individual animals. The DNA profile of each dog could be screened for all known genetic disease and will be useful in counselling breeders. As part of the pre‐breeding examination, DNA profiles of prospective parents could be compared, and the probability of offspring being affected with genetic disorders or inheriting desirable traits could be calculated. Once we can examine thousands of genes of individuals easily, we have powerful tools to reduce the frequency of, or eliminate, deleterious genes from a population. When we understand polygenic inheritance, we can potentially eliminate whole groups of deleterious genes from populations. The effect of such selection on a widespread basis within a breed could rapidly improve health within a few generations. However, until we have enough information on gene interaction, we will not know whether some of these genes have other functions that we wish to retain. And, other population effects should not be ignored. At least initially it may be best to use this new genetic information to avoid mating combinations that we know will produce affected animals, rather than to eliminate whole groups of genes from a population. This is particularly important for breeds with small gene pools, where it is difficult to maintain genetic diversity. Finally, we will eventually have enough information about canine gene function to select for specific genes encoding desirable traits and increase their frequencies in a population. This is similar to breeding practices that have been applied to animals for hundreds of years. The difference is that we will have a large pool of objective data that we can use rapidly on many individuals at a time. This has great potential to improve the health of the dog population as a whole. However, if we or our breeder clients make an error, we can inadvertently cause harm through massive, rapid selection. Therefore, we should probably not be advising clients on polygenic traits or recommend large scale changes in gene frequencies in populations until much more knowledge of gene interaction is obtained. By then it is likely that computer modelling will be available to predict the effect of changing one or several gene frequencies in a dog population over time. And as new mutations are likely to arise in the future, these tools will be needed indefinitely to detect, treat and eliminate genetic disorders from dog populations. Information available from genetic research will only be useful in improving canine health if veterinarians have the knowledge and skills to use it ethically and responsibly. There is not only a great potential to improve overall canine health through genetic selection, but also the potential to do harm if we fail to maintain genetic diversity. Our profession must be in a position to correctly advise clients on the application of this information to individual dogs as well as to populations of dogs, and particularly purebred dogs. 相似文献
16.
There have been considerable recent advancements in animal breeding and genetics relevant to disease control in cattle, which can now be utilised as part of an overall programme for improved cattle health. This review summarises the contribution of genetic makeup to differences in resistance to many diseases affecting cattle. Significant genetic variation in susceptibility to disease does exist among cattle suggesting that genetic selection for improved resistance to disease will be fruitful. Deficiencies in accurately recorded data on individual animal susceptibility to disease are, however, currently hindering the inclusion of health and disease resistance traits in national breeding goals. Developments in 'omics' technologies, such as genomic selection, may help overcome some of the limitations of traditional breeding programmes and will be especially beneficial in breeding for lowly heritable disease traits that only manifest themselves following exposure to pathogens or environmental stressors in adulthood. However, access to large databases of phenotypes on health and disease will still be necessary. This review clearly shows that genetics make a significant contribution to the overall health and resistance to disease in cattle. Therefore, breeding programmes for improved animal health and disease resistance should be seen as an integral part of any overall national disease control strategy. 相似文献
17.
Research on the structure of the ovine major histocompatibility complex (MHC), Ovar-Mhc, and its association with resistance to various diseases in sheep has received increasing attention during recent years. The term 'resistance' is used to denote the capacity of an animal to defend itself against disease or to withstand the effects of a harmful environmental agent. The Ovar-Mhc is poorly characterised when compared to MHCs of other domestic animals. However, its basic structure is similar to that of other animals, comprising Class I, II and III regions. Products of the Class I and II genes, the histocompatibility molecules, are of paramount importance as these present antigens to T-lymphocytes, thereby eliciting immune responses. Several studies have been conducted in sheep on the involvement of MHC genes/antigens in genetic resistance to diseases, the majority being concerned with gastrointestinal nematodes. Studies on resistance to footrot, Johne's disease and bovine leukaemia virus (BLV)-induced leukaemogenesis have also been reported. Genes of all three regions were implicated in the disease association studies. In addition to disease resistance, Ovar-Mhc genes have been found to be associated with traits such as marbling and birthweight. The use of genetic markers from within the Ovar-Mhc may be useful, via marker-assisted selection, for increasing resistance to various diseases provided they do not impact negatively on other economically-important traits. This review summarises current knowledge of the role of Ovar-Mhc in genetic resistance to diseases in sheep. 相似文献
18.
Innes EA Bartley PM Rocchi M Benavidas-Silvan J Burrells A Hotchkiss E Chianini F Canton G Katzer F 《Veterinary parasitology》2011,180(1-2):155-163
Protozoan parasites are among some of the most successful organisms worldwide, being able to live and multiply within a very wide range of hosts. The diseases caused by these parasites cause significant production losses in the livestock sector involving reproductive failure, impaired weight gain, contaminated meat, reduced milk yields and in severe cases, loss of the animal. In addition, some protozoan parasites affecting livestock such as Toxoplasma gondii and Cryptosporidium parvum may also be transmitted to humans where they can cause serious disease. Data derived from experimental models of infection in ruminant species enables the study of the interactions between parasite and host. How the parasite initiates infection, becomes established and multiplies within the host and the critical pathways that may lead to a disease outcome are all important to enable the rational design of appropriate intervention strategies. Once the parasites invade the hosts they induce both innate and adaptive immune responses and the induction and function of these immune responses are critical in determining the outcome of the infection. Vaccines offer green solutions to control disease as they are sustainable, reducing reliance on pharmacological drugs and pesticides. The use of vaccines has multiple benefits such as improving animal health and welfare by controlling animal infections and infestations; improving public health by controlling zoonoses and food borne pathogens in animals; solving problems associated with resistance to acaricides, antibiotics and anthelmintics; keeping animals and the environment free of chemical residues and maintaining biodiversity. All of these attributes should lead to improved sustainability of animal production and economic benefit. Using different protozoan parasitic diseases as examples this paper will discuss various approaches used to develop vaccines to protect against disease in livestock and discuss the relative merits of using live versus killed vaccine preparations. A range of different vaccination targets and strategies will be discussed to help protect against: acute disease, congenital infection and abortion, persistence of zoonotic pathogens in tissues of food animals and passive transfer of immunity to neonates. 相似文献
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20.
Studies of the molecular biology of lymphoid cells have markedly increased our understanding of how millions of different antibodies can be synthesized by a single animal. To date, the most detailed understanding has been achieved for the mouse, primarily because of the relatively greater experimental availability of this species. These studies, as well as those involving other species, have shown that the complete genes for antibody polypeptide chains are assembled from disparate genetic elements which are originally widely separated in the genome. The assembly process itself, together with the coding information present in the germ line genetic elements, contributes to the diversity of structure (and thus combining specificities) shown by mature antibody molecules. Specifically, the diversity of structure characteristic of antibody variable regions is due to three distinct mechanisms: innate variability of germ line genes; mismatching of individual gene segments during their somatic rearrangement leading to junctional diversity; and somatic mutation in variable region genetic material during or after the rearrangement. These processes lead to the wide array of combining specificities that permit the humoral immune system of a mature animal to interact with essentially any non-self antigen which it encounters. Complex genetic rearrangements are also responsible for the class switching phenomenon long known to be characteristic of the humoral immune response. A form of homologous recombination between constant region genes, possibly mediated by specific "switching" enzymes, is now believed to be involved in this phenomenon. It is also currently believed that the restriction of gene rearrangement processes to one of the two possible chromosomes of a diploid pair in each cell is responsible for the phenomenon of allelic exclusion that has long been associated with the normal functioning of mammalian B-cells. 相似文献