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Sánchez-Arcila JC, Jensen KDC. Forward Genetics in Apicomplexa Biology: The Host Side of the Story. Front Cell Infect Microbiol 2022; 12:878475. [PMID: 35646724 PMCID: PMC9133346 DOI: 10.3389/fcimb.2022.878475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 03/31/2022] [Indexed: 11/13/2022] Open
Abstract
Forward genetic approaches have been widely used in parasitology and have proven their power to reveal the complexities of host-parasite interactions in an unbiased fashion. Many aspects of the parasite’s biology, including the identification of virulence factors, replication determinants, antibiotic resistance genes, and other factors required for parasitic life, have been discovered using such strategies. Forward genetic approaches have also been employed to understand host resistance mechanisms to parasitic infection. Here, we will introduce and review all forward genetic approaches that have been used to identify host factors involved with Apicomplexa infections, which include classical genetic screens and QTL mapping, GWAS, ENU mutagenesis, overexpression, RNAi and CRISPR-Cas9 library screens. Collectively, these screens have improved our understanding of host resistance mechanisms, immune regulation, vaccine and drug designs for Apicomplexa parasites. We will also discuss how recent advances in molecular genetics give present opportunities to further explore host-parasite relationships.
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Affiliation(s)
- Juan C. Sánchez-Arcila
- Department of Molecular and Cell Biology, University of California Merced, Merced, CA, United States
| | - Kirk D. C. Jensen
- Department of Molecular and Cell Biology, University of California Merced, Merced, CA, United States
- Health Science Research Institute, University of California, Merced, Merced, CA, United States
- *Correspondence: Kirk D. C. Jensen,
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Attree E, Sanchez-Arsuaga G, Jones M, Xia D, Marugan-Hernandez V, Blake D, Tomley F. Controlling the causative agents of coccidiosis in domestic chickens; an eye on the past and considerations for the future. CABI AGRICULTURE AND BIOSCIENCE 2021; 2:37. [PMID: 34604790 PMCID: PMC8475900 DOI: 10.1186/s43170-021-00056-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 09/06/2021] [Indexed: 05/07/2023]
Abstract
Coccidiosis is a potentially severe enteritis caused by species of obligate intracellular parasites of the genus Eimeria. These parasites cause significant economic losses to the poultry industry, predominantly due to compromised efficiency of production as well as the cost of control. These losses were recently estimated to cost chicken producers approximately £10.4 billion worldwide annually. High levels of Eimeria infection cause clinical coccidiosis which is a significant threat to poultry welfare, and a pre-disposing contributory factor for necrotic enteritis. Control of Eimeria parasites and coccidiosis is therefore an important endeavour; multiple approaches have been developed and these are often deployed together. This review summarises current trends in strategies for control of Eimeria, focusing on three main areas: good husbandry, chemoprophylaxis and vaccination. There is currently no "perfect solution" and there are advantages and limitations to all existing methods. Therefore, the aim of this review is to present current control strategies and suggest how these may develop in the future.
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Affiliation(s)
- Elizabeth Attree
- Department of Pathobiology and Population Sciences, The Royal Veterinary College, North Mymms, Hertfordshire, United Kingdom
| | - Gonzalo Sanchez-Arsuaga
- Department of Pathobiology and Population Sciences, The Royal Veterinary College, North Mymms, Hertfordshire, United Kingdom
| | - Michelle Jones
- Department of Pathobiology and Population Sciences, The Royal Veterinary College, North Mymms, Hertfordshire, United Kingdom
| | - Dong Xia
- Department of Clinical Science and Services, The Royal Veterinary College, North Mymms, Hertfordshire, United Kingdom
| | - Virginia Marugan-Hernandez
- Department of Pathobiology and Population Sciences, The Royal Veterinary College, North Mymms, Hertfordshire, United Kingdom
| | - Damer Blake
- Department of Pathobiology and Population Sciences, The Royal Veterinary College, North Mymms, Hertfordshire, United Kingdom
| | - Fiona Tomley
- Department of Pathobiology and Population Sciences, The Royal Veterinary College, North Mymms, Hertfordshire, United Kingdom
- UKRI GCRF One Health Poultry Hub, Ahmedabad, India
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Mohsin M, Abbas RZ, Yin G, Sindhu ZUD, Abbas A, Huang Z, Aleem MT, Saeed Z, Afzal MZ, Ejaz A, Shoaib M. Probiotics as therapeutic, antioxidant and immunomodulatory agents against poultry coccidiosis. WORLD POULTRY SCI J 2021. [DOI: 10.1080/00439339.2021.1883412] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Muhammad Mohsin
- College of Life Science and College of Animal Sciences (College of Bee Science), Fujian Agriculture and Forestry University, Fuzhou, Fujian Province, China
- Engineering Laboratory of Animal Pharmaceuticals and College of Animal Sciences (College of Bee Science), Fujian Agriculture and Forestry University, Fuzhou, Fujian Province, China
- Department of Parasitology, University of Agriculture, Faisalabad, Pakistan
| | - Rao Zahid Abbas
- Department of Parasitology, University of Agriculture, Faisalabad, Pakistan
| | - Guangwen Yin
- Engineering Laboratory of Animal Pharmaceuticals and College of Animal Sciences (College of Bee Science), Fujian Agriculture and Forestry University, Fuzhou, Fujian Province, China
| | - Zia-Ud-Din Sindhu
- Department of Parasitology, University of Agriculture, Faisalabad, Pakistan
| | - Asghar Abbas
- Faculty of Veterinary and Animal Sciences, Muhammad Nawaz Shareef University of Agriculture, Multan, Pakistan
| | - Zhijian Huang
- Engineering Laboratory of Animal Pharmaceuticals and College of Animal Sciences (College of Bee Science), Fujian Agriculture and Forestry University, Fuzhou, Fujian Province, China
| | - Muhammad Tahir Aleem
- Department of Parasitology, University of Agriculture, Faisalabad, Pakistan
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing Jiangsu, China
| | - Zohaib Saeed
- Department of Parasitology, University of Agriculture, Faisalabad, Pakistan
| | | | - Adil Ejaz
- Department of Parasitology, University of Agriculture, Faisalabad, Pakistan
| | - Muhammad Shoaib
- Institute of Microbiology, University of Agriculture, Faisalabad, Pakistan
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4
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Affiliation(s)
- P.M. Hocking
- Roslin Institute, Roslin, Midlothian, Scotland, EH25 9PS
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Bresadola L, Caseys C, Castiglione S, Buerkle CA, Wegmann D, Lexer C. Admixture mapping in interspecific Populus hybrids identifies classes of genomic architectures for phytochemical, morphological and growth traits. THE NEW PHYTOLOGIST 2019; 223:2076-2089. [PMID: 31104343 PMCID: PMC6771622 DOI: 10.1111/nph.15930] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2018] [Accepted: 05/06/2019] [Indexed: 05/03/2023]
Abstract
The genomic architecture of functionally important traits is key to understanding the maintenance of reproductive barriers and trait differences when divergent populations or species hybridize. We conducted a genome-wide association study (GWAS) to study trait architecture in natural hybrids of two ecologically divergent Populus species. We genotyped 472 seedlings from a natural hybrid zone of Populus alba and Populus tremula for genome-wide markers from reduced representation sequencing, phenotyped the plants in common gardens for 46 phytochemical (phenylpropanoid), morphological and growth traits, and used a Bayesian polygenic model for mapping. We detected three classes of genomic architectures: traits with finite, detectable associations of genetic loci with phenotypic variation in addition to highly polygenic heritability; traits with indications for polygenic heritability only; and traits with no detectable heritability. For the first class, we identified genome regions with plausible candidate genes for phenylpropanoid biosynthesis or its regulation, including MYB transcription factors and glycosyl transferases. GWAS in natural, recombinant hybrids represent a promising step towards resolving the genomic architecture of phenotypic traits in long-lived species. This facilitates the fine-mapping and subsequent functional characterization of genes and networks causing differences in hybrid performance and fitness.
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Affiliation(s)
- Luisa Bresadola
- Department of BiologyUniversity of FribourgChemin du Musée 101700FribourgSwitzerland
| | - Céline Caseys
- Department of BiologyUniversity of FribourgChemin du Musée 101700FribourgSwitzerland
- Department of Plant SciencesUniversity of California DavisOne Shields AvenueDavisCA95616USA
| | - Stefano Castiglione
- Department of Chemistry and Biology ‘A. Zambelli’University of SalernoVia Giovanni Paolo II 13284084Fisciano, SalernoItaly
| | - C. Alex Buerkle
- Department of BotanyUniversity of Wyoming1000 E. University Ave.LaramieWY82071USA
| | - Daniel Wegmann
- Department of BiologyUniversity of FribourgChemin du Musée 101700FribourgSwitzerland
- Swiss Institute of Bioinformatics1700FribourgSwitzerland
| | - Christian Lexer
- Department of BiologyUniversity of FribourgChemin du Musée 101700FribourgSwitzerland
- Department of Botany and Biodiversity ResearchFaculty of Life SciencesUniversity of ViennaRennweg 12A‐1030ViennaAustria
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Wang X, Zou W, Yu H, Lin Y, Dai G, Zhang T, Zhang G, Xie K, Wang J, Shi H. RNA Sequencing Analysis of Chicken Cecum Tissues Following Eimeria tenella Infection in Vivo. Genes (Basel) 2019; 10:E420. [PMID: 31159150 PMCID: PMC6627390 DOI: 10.3390/genes10060420] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 05/28/2019] [Accepted: 05/29/2019] [Indexed: 12/15/2022] Open
Abstract
Eimeria tenella (E. tenella) is one of the most frequent and pathogenic species of protozoan parasites of the genus Eimeria that exclusively occupies the cecum, exerting a high economic impact on the poultry industry. To investigate differentially expressed genes (DEGs) in the cecal tissue of Jinghai yellow chickens infected with E. tenella, the molecular response process, and the immune response mechanism during coccidial infection, RNA-seq was used to analyze the cecal tissues of an E. tenella infection group (JS) and an uninfected group (JC) on the seventh day post-infection. The DEGs were screened by functional and pathway enrichment analyses. The results indicated that there were 5477 DEGs (p-value < 0.05) between the JS and the JC groups, of which 2942 were upregulated, and 2535 were downregulated. GO analysis indicated that the top 30 significantly enriched GO terms mainly involved signal transduction, angiogenesis, inflammatory response, and blood vessel development. KEGG analysis revealed that the top significantly enriched signaling pathways included focal adhesion, extracellular matrix-receptor interaction, and peroxisome proliferator-activated receptor. The key DEGs in these pathways included ANGPTL4, ACSL5, VEGFC, MAPK10, and CD44. These genes play an important role in the infection of E. tenella. This study further enhances our understanding of the molecular mechanism of E. tenella infection in chickens.
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Affiliation(s)
- Xiaohui Wang
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, Jiangsu, China.
| | - Wenbin Zou
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, Jiangsu, China.
| | - Hailiang Yu
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, Jiangsu, China.
| | - Yuxin Lin
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, Jiangsu, China.
- Animal Husbandry and Veterinary Station of Kunshan City, Kunshan 215300, Jiangsu, China.
| | - Guojun Dai
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, Jiangsu, China.
| | - Tao Zhang
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, Jiangsu, China.
| | - Genxi Zhang
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, Jiangsu, China.
| | - Kaizhou Xie
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, Jiangsu, China.
| | - Jinyu Wang
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, Jiangsu, China.
| | - Huiqiang Shi
- Jiangsu Jinghai Poultry Group Co., Ltd., Haimen 226100, Jiangsu, China.
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Boulton K, Nolan MJ, Wu Z, Riggio V, Matika O, Harman K, Hocking PM, Bumstead N, Hesketh P, Archer A, Bishop SC, Kaiser P, Tomley FM, Hume DA, Smith AL, Blake DP, Psifidi A. Dissecting the Genomic Architecture of Resistance to Eimeria maxima Parasitism in the Chicken. Front Genet 2018; 9:528. [PMID: 30534137 PMCID: PMC6275401 DOI: 10.3389/fgene.2018.00528] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 10/22/2018] [Indexed: 01/16/2023] Open
Abstract
Coccidiosis in poultry, caused by protozoan parasites of the genus Eimeria, is an intestinal disease with substantial economic impact. With the use of anticoccidial drugs under public and political pressure, and the comparatively higher cost of live-attenuated vaccines, an attractive complementary strategy for control is to breed chickens with increased resistance to Eimeria parasitism. Prior infection with Eimeria maxima leads to complete immunity against challenge with homologous strains, but only partial resistance to challenge with antigenically diverse heterologous strains. We investigate the genetic architecture of avian resistance to E. maxima primary infection and heterologous strain secondary challenge using White Leghorn populations of derived inbred lines, C.B12 and 15I, known to differ in susceptibility to the parasite. An intercross population was infected with E. maxima Houghton (H) strain, followed 3 weeks later by E. maxima Weybridge (W) strain challenge, while a backcross population received a single E. maxima W infection. The phenotypes measured were parasite replication (counting fecal oocyst output or qPCR for parasite numbers in intestinal tissue), intestinal lesion score (gross pathology, scale 0-4), and for the backcross only, serum interleukin-10 (IL-10) levels. Birds were genotyped using a high density genome-wide DNA array (600K, Affymetrix). Genome-wide association study located associations on chromosomes 1, 2, 3, and 5 following primary infection in the backcross population, and a suggestive association on chromosome 1 following heterologous E. maxima W challenge in the intercross population. This mapped several megabases away from the quantitative trait locus (QTL) linked to the backcross primary W strain infection, suggesting different underlying mechanisms for the primary- and heterologous secondary- responses. Underlying pathways for those genes located in the respective QTL for resistance to primary infection and protection against heterologous challenge were related mainly to immune response, with IL-10 signaling in the backcross primary infection being the most significant. Additionally, the identified markers associated with IL-10 levels exhibited significant additive genetic variance. We suggest this is a phenotype of interest to the outcome of challenge, being scalable in live birds and negating the requirement for single-bird cages, fecal oocyst counts, or slaughter for sampling (qPCR).
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Affiliation(s)
- Kay Boulton
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Edinburgh, United Kingdom
| | - Matthew J Nolan
- Department of Pathobiology and Population Sciences, Royal Veterinary College, University of London, London, United Kingdom
| | - Zhiguang Wu
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Edinburgh, United Kingdom
| | - Valentina Riggio
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Edinburgh, United Kingdom
| | - Oswald Matika
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Edinburgh, United Kingdom
| | - Kimberley Harman
- Department of Pathobiology and Population Sciences, Royal Veterinary College, University of London, London, United Kingdom
| | - Paul M Hocking
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Edinburgh, United Kingdom
| | - Nat Bumstead
- Enteric Immunology Group and Genetics and Genomics Group, Pirbright Institute, Woking, United Kingdom
| | - Pat Hesketh
- Enteric Immunology Group and Genetics and Genomics Group, Pirbright Institute, Woking, United Kingdom
| | - Andrew Archer
- Enteric Immunology Group and Genetics and Genomics Group, Pirbright Institute, Woking, United Kingdom
| | - Stephen C Bishop
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Edinburgh, United Kingdom
| | - Pete Kaiser
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Edinburgh, United Kingdom
| | - Fiona M Tomley
- Department of Pathobiology and Population Sciences, Royal Veterinary College, University of London, London, United Kingdom
| | - David A Hume
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Edinburgh, United Kingdom.,Mater Research Institute, The University of Queensland, Brisbane, St. Lucia, QLD, Australia
| | - Adrian L Smith
- Enteric Immunology Group and Genetics and Genomics Group, Pirbright Institute, Woking, United Kingdom.,Department of Zoology, Sir Peter Medawar Building for Pathogen Research, University of Oxford, Oxford, United Kingdom
| | - Damer P Blake
- Department of Pathobiology and Population Sciences, Royal Veterinary College, University of London, London, United Kingdom
| | - Androniki Psifidi
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Edinburgh, United Kingdom.,Department of Pathobiology and Population Sciences, Royal Veterinary College, University of London, London, United Kingdom.,Department of Clinical Sciences and Services, Royal Veterinary College, University of London, Hatfield, United Kingdom
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Boulton K, Nolan MJ, Wu Z, Psifidi A, Riggio V, Harman K, Bishop SC, Kaiser P, Abrahamsen MS, Hawken R, Watson KA, Tomley FM, Blake DP, Hume DA. Phenotypic and genetic variation in the response of chickens to Eimeria tenella induced coccidiosis. Genet Sel Evol 2018; 50:63. [PMID: 30463512 PMCID: PMC6249784 DOI: 10.1186/s12711-018-0433-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 11/14/2018] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Coccidiosis is a major contributor to losses in poultry production. With emerging constraints on the use of in-feed prophylactic anticoccidial drugs and the relatively high costs of effective vaccines, there are commercial incentives to breed chickens with greater resistance to this important production disease. To identify phenotypic biomarkers that are associated with the production impacts of coccidiosis, and to assess their covariance and heritability, 942 Cobb500 commercial broilers were subjected to a defined challenge with Eimeria tenella (Houghton). Three traits were measured: weight gain (WG) during the period of infection, caecal lesion score (CLS) post mortem, and the level of a serum biomarker of intestinal inflammation, i.e. circulating interleukin 10 (IL-10), measured at the height of the infection. RESULTS Phenotypic analysis of the challenged chicken cohort revealed a significant positive correlation between CLS and IL-10, with significant negative correlations of both these traits with WG. Eigenanalysis of phenotypic covariances between measured traits revealed three distinct eigenvectors. Trait weightings of the first eigenvector, (EV1, eigenvalue = 59%), were biologically interpreted as representing a response of birds that were susceptible to infection, with low WG, high CLS and high IL-10. Similarly, the second eigenvector represented infection resilience/resistance (EV2, 22%; high WG, low CLS and high IL-10), and the third eigenvector tolerance (EV3, 19%; high WG, high CLS and low IL-10), respectively. Genome-wide association studies (GWAS) identified two SNPs that were associated with WG at the suggestive level. CONCLUSIONS Eigenanalysis separated the phenotypic impact of a defined challenge with E. tenella on WG, caecal inflammation/pathology, and production of IL-10 into three major eigenvectors, indicating that the susceptibility-resistance axis is not a single continuous quantitative trait. The SNPs identified by the GWAS for body weight were located in close proximity to two genes that are involved in innate immunity (FAM96B and RRAD).
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Affiliation(s)
- Kay Boulton
- The Roslin Institute, University of Edinburgh, Easter Bush, Midlothian, UK
| | - Matthew J. Nolan
- Department of Pathobiology and Population Sciences, Royal Veterinary College, University of London, Hatfield, UK
| | - Zhiguang Wu
- The Roslin Institute, University of Edinburgh, Easter Bush, Midlothian, UK
| | - Androniki Psifidi
- The Roslin Institute, University of Edinburgh, Easter Bush, Midlothian, UK
- Department of Clinical Sciences and Services, Royal Veterinary College, University of London, Hatfield, UK
| | - Valentina Riggio
- The Roslin Institute, University of Edinburgh, Easter Bush, Midlothian, UK
| | - Kimberley Harman
- Department of Pathobiology and Population Sciences, Royal Veterinary College, University of London, Hatfield, UK
| | - Stephen C. Bishop
- The Roslin Institute, University of Edinburgh, Easter Bush, Midlothian, UK
| | - Pete Kaiser
- The Roslin Institute, University of Edinburgh, Easter Bush, Midlothian, UK
| | | | - Rachel Hawken
- Cobb-Vantress Inc., PO Box 1030, Siloam Springs, AR USA
| | - Kellie A. Watson
- The Roslin Institute, University of Edinburgh, Easter Bush, Midlothian, UK
| | - Fiona M. Tomley
- Department of Pathobiology and Population Sciences, Royal Veterinary College, University of London, Hatfield, UK
| | - Damer P. Blake
- Department of Pathobiology and Population Sciences, Royal Veterinary College, University of London, Hatfield, UK
| | - David A. Hume
- The Roslin Institute, University of Edinburgh, Easter Bush, Midlothian, UK
- Mater Research Institute, University of Queensland, Brisbane, St. Lucia, QLD, Brisbane, Australia
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Zampiga M, Flees J, Meluzzi A, Dridi S, Sirri F. Application of omics technologies for a deeper insight into quali-quantitative production traits in broiler chickens: A review. J Anim Sci Biotechnol 2018; 9:61. [PMID: 30214720 PMCID: PMC6130060 DOI: 10.1186/s40104-018-0278-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 07/03/2018] [Indexed: 12/12/2022] Open
Abstract
The poultry industry is continuously facing substantial and different challenges such as the increasing cost of feed ingredients, the European Union's ban of antibiotic as growth promoters, the antimicrobial resistance and the high incidence of muscle myopathies and breast meat abnormalities. In the last decade, there has been an extraordinary development of many genomic techniques able to describe global variation of genes, proteins and metabolites expression level. Proper application of these cutting-edge omics technologies (mainly transcriptomics, proteomics and metabolomics) paves the possibility to understand much useful information about the biological processes and pathways behind different complex traits of chickens. The current review aimed to highlight some important knowledge achieved through the application of omics technologies and proteo-genomics data in the field of feed efficiency, nutrition, meat quality and disease resistance in broiler chickens.
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Affiliation(s)
- Marco Zampiga
- Department of Agricultural and Food Sciences, Alma Mater Studiorum - University of Bologna, Via del Florio, 2, 40064 Ozzano dell’Emilia, Italy
| | - Joshua Flees
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR 72701 USA
| | - Adele Meluzzi
- Department of Agricultural and Food Sciences, Alma Mater Studiorum - University of Bologna, Via del Florio, 2, 40064 Ozzano dell’Emilia, Italy
| | - Sami Dridi
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR 72701 USA
| | - Federico Sirri
- Department of Agricultural and Food Sciences, Alma Mater Studiorum - University of Bologna, Via del Florio, 2, 40064 Ozzano dell’Emilia, Italy
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The Evolutionary Biology, Ecology and Epidemiology of Coccidia of Passerine Birds. ADVANCES IN PARASITOLOGY 2018. [PMID: 29530310 DOI: 10.1016/bs.apar.2018.01.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Coccidia are intracellular parasites of the phylum Apicomplexa that cause a range of pathologies collectively termed coccidiosis. Species of coccidia of commercial importance have been well studied, with the effect of other species on passerine birds receiving increasing attention. In this chapter, we review the literature on coccidia in passerines, with a particular focus on wild populations. The taxonomy and life cycle of passerine coccidia are covered, as is their impact on the health of passerines, their epidemiology and their role in parasite-mediated natural and sexual selection. Coccidia can pose a significant threat to the health of wild passerine populations, and high rates of mortality have been observed in some studies. We examine some of the genetic factors that influence host resistance to coccidia and discuss how these parasites may be important in relation to sexually selected traits. General patterns are beginning to emerge with regard to the epidemiology of the parasites, and the influence of different aspects of the host's ecology on the prevalence and intensity of coccidia is being revealed. We examine these, as well exceptions, in addition to the phenomenon of diurnal oocyst shedding that can bias studies if not accounted for. Finally, we discuss potential future directions for research on coccidia in passerines and the importance of understanding parasite ecology in the management of threatened species.
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Comparative Response of the Nigerian Indigenous and Broiler Chickens to a Field Caecal Isolate of Eimeria Oocysts. J Pathog 2017; 2017:2674078. [PMID: 28523192 PMCID: PMC5421090 DOI: 10.1155/2017/2674078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Accepted: 01/11/2017] [Indexed: 11/17/2022] Open
Abstract
Response of Nigerian indigenous (local) and broiler chickens to experimental Eimeria infections was investigated by measures of clinical signs, packed cell volume (PCV), body weights (BW), feed consumption, faecal oocyst counts (oocyst per gram), and microscopic intestinal lesions. Three-week-old chickens of each breed received single pulse infections with 2500, 5000, and 100.000 sporulated Eimeria oocysts. Infected birds were dull and passed bloody diarrhoea. OPG showed a dose related response but no significant difference between groups (P > 0.05). OPG was significantly higher in local chickens (P < 0.05) and varied significantly with time (P < 0.05). PCV declined significantly in infected birds within breeds and groups (P < 0.05); however, the decline in PCV was significantly greater in broilers (P < 0.05). Both breeds had significant BW gains (P < 0.05). BW gain varied between groups being significantly higher in the uninfected control broilers than in the infected broilers (P < 0.05). Comparatively, broilers gained significantly more BW than their local counterparts (P < 0.05). Feed intake increased significantly with time (P < 0.05) in both breeds. The Eimeria isolate was pathogenic to both breeds of chicken although clinical signs and lesions were more severe in indigenous chickens suggesting the breed's more susceptibility.
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12
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Bozkurt M, Ege G, Aysul N, Akşit H, Tüzün AE, Küçükyılmaz K, Borum AE, Uygun M, Akşit D, Aypak S, Şimşek E, Seyrek K, Koçer B, Bintaş E, Orojpour A. Effect of anticoccidial monensin with oregano essential oil on broilers experimentally challenged with mixed Eimeria spp. Poult Sci 2016; 95:1858-68. [PMID: 26976910 DOI: 10.3382/ps/pew077] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/27/2016] [Indexed: 11/20/2022] Open
Abstract
Essential oil of oregano ( OEO: ) has proven to be a potential candidate for controlling chicken coccidiosis. The aim of the current study is to determine whether OEO and an approved anticoccidial, monensin sodium ( MON: ), as in-feed supplements could create a synergism when combined at low dosages. Day-old broiler chickens were separated into six equal groups with six replicate pens of 36 birds. One of the groups was given a basal diet and served as the control ( CNT: ). The remaining groups received the basal diet supplemented with 100 mg/kg MON, 50 mg/kg MON, 24 mg/kg OEO, 12 mg/kg OEO, or 50 mg/kg MON + 12 mg/kg OEO. All of the chickens were challenged with field-type mixed Eimeria species at 12 d of age. Following the infection (i.e., d 13 to 42), the greatest growth gains and lowest feed conversion ratio values were recorded for the group of birds fed 100 mg/kg MON (P < 0.05), whereas results for the CNT treatment were inferior. Dietary OEO supplementations could not support growth to a level comparable with the MON (100 mg/kg). The MON programs were more efficacious in reducing fecal oocyst numbers compared to CNT and OEO treatments (P < 0.05). Serum malondialdehyde and nitric oxide concentrations were decreased (P < 0.01), whereas superoxide dismutase (P < 0.05) and total antioxidant status (P < 0.01) were increased in response to dietary medication with MON and OEO. All MON and OEO treatments conferred intestinal health benefits to chickens by improving their morphological development and enzymatic activities. The results suggest that OEO supported the intestinal absorptive capacity and antioxidant defense system during Eimeria infection; however, it displayed little direct activity on the reproductive capacity of Eimeria This might be the reason for inferior compensatory growth potential of OEO compared to that MON following the challenge. Combination MON with OEO was not considered to show promise for controlling chicken coccidiosis because of the lack of a synergistic or additive effect.
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Affiliation(s)
- M Bozkurt
- General Directorate of Research, Erbeyli Experimental Station, Aydın-Turkey
| | - G Ege
- General Directorate of Research, Erbeyli Experimental Station, Aydın-Turkey
| | - N Aysul
- Department of Parasitology, Faculty of Veterinary, Adnan Menderes University, Aydın-Turkey
| | - H Akşit
- Department of Biochemistry, Faculty of Veterinary, Balıkesir University, Balıkesir-Turkey
| | - A E Tüzün
- Adnan Menderes University Koçarlı Vocational Scholl, South Campus, Aydın, Turkey
| | - K Küçükyılmaz
- Department of Animal Science, Faculty of Agriculture, Eskişehir Osmangazi University, Eskişehir-Turkey
| | - A E Borum
- Department of Microbiology, Faculty of Veterinary, Balıkesir University, Balıkesir-Turkey
| | - M Uygun
- Adnan Menderes University Koçarlı Vocational Scholl, South Campus, Aydın, Turkey
| | - D Akşit
- Department of Pharmacology and Toxicology, Faculty of Veterinary, Balıkesir University, Balıkesir-Turkey
| | - S Aypak
- Department of Parasitology, Faculty of Veterinary, Adnan Menderes University, Aydın-Turkey
| | - E Şimşek
- Department of Parasitology, Faculty of Veterinary, Erciyes Üniversitesi, Kayseri-Turkey
| | - K Seyrek
- Department of Medicinal Biochemistry, Faculty of Medicine, Balıkesir University, Balıkesir-Turkey
| | - B Koçer
- General Directorate of Research, Erbeyli Experimental Station, Aydın-Turkey
| | - E Bintaş
- General Directorate of Research, Erbeyli Experimental Station, Aydın-Turkey
| | - A Orojpour
- Department of Animal Science, Faculty of Agriculture, Eskişehir Osmangazi University, Eskişehir-Turkey
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Hamzic E, Bed'Hom B, Juin H, Hawken R, Abrahamsen MS, Elsen JM, Servin B, Pinard-van der Laan MH, Demeure O. Large-scale investigation of the parameters in response to Eimeria maxima challenge in broilers. J Anim Sci 2016; 93:1830-40. [PMID: 26020204 DOI: 10.2527/jas.2014-8592] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Coccidiosis, a parasitic disease of the intestinal tract caused by members of the genera Eimeria and Isospora, is one of the most common and costly diseases in chicken. The aims of this study were to assess the effect of the challenge and level of variability of measured parameters in chickens during the challenge with Eimeria maxima. Furthermore, this study aimed to investigate which parameters are the most relevant indicators of the health status. Finally, the study also aimed to estimate accuracy of prediction for traits that cannot be measured on large scale (such as intestinal lesion score and fecal oocyst count) using parameters that can easily be measured on all animals. The study was performed in 2 parts: a pilot challenge on 240 animals followed by a large-scale challenge on 2,024 animals. In both experiments, animals were challenged with 50,000 Eimeria maxima oocysts at 16 d of age. In the pilot challenge, all animals were measured for BW gain, plasma coloration, hematocrit, and rectal temperature and, in addition, a subset of 48 animals was measured for oocyst count and the intestinal lesion score. All animals from the second challenge were measured for BW gain, plasma coloration, and hematocrit whereas a subset of 184 animals was measured for intestinal lesion score, fecal oocyst count, blood parameters, and plasma protein content and composition. Most of the parameters measured were significantly affected by the challenge. Lesion scores for duodenum and jejunum (P < 0.001), oocyst count (P < 0.05), plasma coloration for the optical density values between 450 and 490 nm (P < 0.001), albumin (P < 0.001), α1-globulin (P < 0.01), α2-globulin (P < 0.001), α3-globulin (P < 0.01), and β2-globulin (P < 0.001) were the most strongly affected parameters and expressed the greatest levels of variation. Plasma protein profiles proved to be a new, reliable parameter for measuring response to Eimeria maxima. Prediction of intestinal lesion score and fecal oocyst count using the other parameters measured was not very precise (R2 < 0.7). The study was successfully performed in real raising conditions on a large scale. Finally, we observed a high variability in response to the challenge, suggesting that broilers' response to Eimeria maxima has a strong genetic determinism, which may be improved by genetic selection.
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14
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Hamzić E, Buitenhuis B, Hérault F, Hawken R, Abrahamsen MS, Servin B, Elsen JM, Pinard-van der Laan MH, Bed'Hom B. Genome-wide association study and biological pathway analysis of the Eimeria maxima response in broilers. Genet Sel Evol 2015; 47:91. [PMID: 26607727 PMCID: PMC4659166 DOI: 10.1186/s12711-015-0170-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2015] [Accepted: 11/05/2015] [Indexed: 02/22/2023] Open
Abstract
Background Coccidiosis is the most common and costly disease in the poultry industry and is caused by protozoans of the Eimeria genus. The current control of coccidiosis, based on the use of anticoccidial drugs and vaccination, faces serious obstacles such as drug resistance and the high costs for the development of efficient vaccines, respectively. Therefore, the current control programs must be expanded with complementary approaches such as the use of genetics to improve the host response to Eimeria infections. Recently, we have performed a large-scale challenge study on Cobb500 broilers using E. maxima for which we investigated variability among animals in response to the challenge. As a follow-up to this challenge study, we performed a genome-wide association study (GWAS) to identify genomic regions underlying variability of the measured traits in the response to Eimeria maxima in broilers. Furthermore, we conducted a post-GWAS functional analysis to increase our biological understanding of the underlying response to Eimeria maxima challenge. Results In total, we identified 22 single nucleotide polymorphisms (SNPs) with q value <0.1 distributed across five chromosomes. The highly significant SNPs were associated with body weight gain (three SNPs on GGA5, one SNP on GGA1 and one SNP on GGA3), plasma coloration measured as optical density at wavelengths in the range 465–510 nm (10 SNPs and all on GGA10) and the percentage of β2-globulin in blood plasma (15 SNPs on GGA1 and one SNP on GGA2). Biological pathways related to metabolic processes, cell proliferation, and primary innate immune processes were among the most frequent significantly enriched biological pathways. Furthermore, the network-based analysis produced two networks of high confidence, with one centered on large tumor suppressor kinase 1 (LATS1) and 2 (LATS2) and the second involving the myosin heavy chain 6 (MYH6). Conclusions We identified several strong candidate genes and genomic regions associated with traits measured in response to Eimeria maxima in broilers. Furthermore, the post-GWAS functional analysis indicates that biological pathways and networks involved in tissue proliferation and repair along with the primary innate immune response may play the most important role during the early stage of Eimeria maxima infection in broilers. Electronic supplementary material The online version of this article (doi:10.1186/s12711-015-0170-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Edin Hamzić
- UMR1313 Animal Genetics and Integrative Biology Unit, AgroParisTech, 16 rue Claude Bernard, 75005, Paris, France. .,UMR1313 Animal Genetics and Integrative Biology Unit, INRA, Domaine de Vilvert, 78350, Jouy-en-Josas, France. .,Department of Molecular Biology and Genetics, Center for Quantitative Genetics and Genomics, Aarhus University, Blichers Allé 20, P.O. Box 50, 8830, Tjele, Denmark.
| | - Bart Buitenhuis
- Department of Molecular Biology and Genetics, Center for Quantitative Genetics and Genomics, Aarhus University, Blichers Allé 20, P.O. Box 50, 8830, Tjele, Denmark.
| | - Frédéric Hérault
- UMR1348 Physiology, Environment and Genetics for the Animal and Livestock Systems Unit, INRA, Domaine de la Prise, 35590, Saint Gilles, France.
| | | | | | - Bertrand Servin
- UMR1388 Genetics, Physiology and Breeding Systems, INRA, 24 chemin de Borde-Rouge, 31326, Castanet-Tolosan, France.
| | - Jean-Michel Elsen
- UMR1388 Genetics, Physiology and Breeding Systems, INRA, 24 chemin de Borde-Rouge, 31326, Castanet-Tolosan, France.
| | - Marie-Hélène Pinard-van der Laan
- UMR1313 Animal Genetics and Integrative Biology Unit, AgroParisTech, 16 rue Claude Bernard, 75005, Paris, France. .,UMR1313 Animal Genetics and Integrative Biology Unit, INRA, Domaine de Vilvert, 78350, Jouy-en-Josas, France.
| | - Bertrand Bed'Hom
- UMR1313 Animal Genetics and Integrative Biology Unit, AgroParisTech, 16 rue Claude Bernard, 75005, Paris, France. .,UMR1313 Animal Genetics and Integrative Biology Unit, INRA, Domaine de Vilvert, 78350, Jouy-en-Josas, France.
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15
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An assessment of opportunities to dissect host genetic variation in resistance to infectious diseases in livestock. Animal 2012; 3:415-36. [PMID: 22444313 DOI: 10.1017/s1751731108003522] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
This paper reviews the evidence for host genetic variation in resistance to infectious diseases for a wide variety of diseases of economic importance in poultry, cattle, pig, sheep and Atlantic salmon. Further, it develops a method of ranking each disease in terms of its overall impact, and combines this ranking with published evidence for host genetic variation and information on the current state of genomic tools in each host species. The outcome is an overall ranking of the amenability of each disease to genomic studies that dissect host genetic variation in resistance. Six disease-based assessment criteria were defined: industry concern, economic impact, public concern, threat to food safety or zoonotic potential, impact on animal welfare and threat to international trade barriers. For each category, a subjective score was assigned to each disease according to the relative strength of evidence, impact, concern or threat posed by that particular disease, and the scores were summed across categories. Evidence for host genetic variation in resistance was determined from available published data, including breed comparison, heritability studies, quantitative trait loci (QTL) studies, evidence of candidate genes with significant effects, data on pathogen sequence and on host gene expression analyses. In total, 16 poultry diseases, 13 cattle diseases, nine pig diseases, 11 sheep diseases and three Atlantic salmon diseases were assessed. The top-ranking diseases or pathogens, i.e. those most amenable to studies dissecting host genetic variation, were Salmonella in poultry, bovine mastitis, Marek's disease and coccidiosis, both in poultry. The top-ranking diseases or pathogens in pigs, sheep and Atlantic salmon were Escherichia coli, mastitis and infectious pancreatic necrosis, respectively. These rankings summarise the current state of knowledge for each disease and broadly, although not entirely, reflect current international research efforts. They will alter as more information becomes available and as genome tools become more sophisticated for each species. It is suggested that this approach could be used to rank diseases from other perspectives as well, e.g. in terms of disease control strategies.
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16
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Shirley MW, Lillehoj HS. The long view: a selective review of 40 years of coccidiosis research. Avian Pathol 2012; 41:111-21. [PMID: 22515530 DOI: 10.1080/03079457.2012.666338] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
This selective review of 40 years of coccidiosis research is one of a number on important diseases of poultry to celebrate the 40th anniversary of the birth of Avian Pathology, the journal of the World Veterinary Poultry Association, and is written for the non-specialist. The intention is to provide a flavour of the field problems and intellectual challenges, with emphasis in the areas of immunology and vaccinology that drove research in the 1970s, and to reflect on research progress since.
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Affiliation(s)
- M W Shirley
- Animal Parasitic Diseases Laboratory, USDA – Agricultural Research Service, Beltsville, MD, 20705, USA.
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17
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Identification of parental line specific effects of MLF2 on resistance to coccidiosis in chickens. BMC Proc 2011; 5 Suppl 4:S21. [PMID: 21645301 PMCID: PMC3108216 DOI: 10.1186/1753-6561-5-s4-s21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND MLF2 was the candidate gene associated with coccidiosis resistance in chickens. Although single marker analysis supported the association between MLF2 and coccidiosis resistance, causative mutation relevant to coccidiosis was not identified yet. Thus, this study suggested segregation analysis of MLF2 haplotype and the association test of the other candidate genes using improved data transformation. RESULTS A haplotype probably originated from one parental line was found out of 4 major haplotypes of MLF2. Frequency of this haplotype was 0.2 in parental chickens and its offspring in 12 families. Allele substitution effect of the MLF2 haplotype originated from a specific line was associated with increased body weight and fecal egg count explaining coccidiosis resistance. Nevertheless Box-Cox transformation was able to improve normality; association test did not produce obvious different results compared with analysis with log transformed phenotype. CONCLUSION Allele substitution effect analysis and classification of MLF2 haplotype identified the segregation of haplotype associated with coccidiosis resistance. The haplotype originated from a specific parental line was associated with improving disease resistance. Estimating effect of MLF2 haplotype on coccidiosis resistance will provide useful information for selecting animals or lines for future study.
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18
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Kim ES, Hong YH, Lillehoj HS. Genetic effects analysis of myeloid leukemia factor 2 and T cell receptor-β on resistance to coccidiosis in chickens. Poult Sci 2010; 89:20-7. [PMID: 20008798 DOI: 10.3382/ps.2009-00351] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Affiliation(s)
- E-S Kim
- Bovine Functional Genomics Laboratory, Animal and Natural Resources Institute, USDA, Beltsville, MD 20705, USA
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19
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Hong YH, Kim ES, Lillehoj HS, Lillehoj EP, Song KD. Association of resistance to avian coccidiosis with single nucleotide polymorphisms in the zyxin gene. Poult Sci 2009; 88:511-8. [PMID: 19211519 DOI: 10.3382/ps.2008-00344] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Our previous genetic studies demonstrated that resistance to avian coccidiosis is linked with microsatellite markers LEI0071 and LEI0101 on chromosome 1. In this study, the associations between parameters of resistance to coccidiosis and single nucleotide polymorphisms (SNP) in 3 candidate genes located between LEI0071 and LEI0101 [zyxin, CD4, and tumor necrosis factor receptor super family 1A (TNFRSF1A)] were determined. The SNP were genotyped in 24 F(1) generation and 290 F(2) generation animals. No SNP were identified in the TNFRSF1A gene, whereas 10 were located in the zyxin gene and 4 in the CD4 gene. At various times following experimental infection of the F(2) generation with Eimeria maxima, BW, fecal oocyst shedding, and plasma levels of carotenoid, nitrite plus nitrate (NO(2)(-) + NO(3)(-)), and interferon-gamma (IFN-gamma) were measured as parameters of resistance. Single marker and haplotype-based tests were applied to determine the associations between the 14 SNP and the parameters of coccidiosis resistance. None of the CD4 SNP were correlated with disease resistance. However, by single marker association, several of the zyxin SNP were significantly associated with carotenoid or NO(2)(-) + NO(3)(-) concentrations. These were the SNP at nucleotide 149 associated with carotenoid at d 3 postinfection (PI), nucleotide 187 with carotenoid at d 6 and 9 PI, and nucleotide 159 with carotenoid between d 3 and 9 PI. In addition, the zyxin SNP at nucleotide 191 was significantly associated with increased levels of NO(2)(-) + NO(3)(-) at d 3 PI. By haplotype association, the zyxin SNP also were found to be highly associated with NO(2)(-) + NO(3)(-) at d 3 PI and increased IFN-gamma at d 6 PI. These results suggest that zyxin is a candidate gene potentially associated with increased resistance to experimental avian coccidiosis.
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Affiliation(s)
- Y H Hong
- Animal Parasitic Diseases Laboratory, Animal and Natural Resources Institute, USDA, Beltsville, MD 20705, USA.
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20
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Pinard-van der Laan MH, Bed'hom B, Coville JL, Pitel F, Feve K, Leroux S, Legros H, Thomas A, Gourichon D, Repérant JM, Rault P. Microsatellite mapping of QTLs affecting resistance to coccidiosis (Eimeria tenella) in a Fayoumi x White Leghorn cross. BMC Genomics 2009; 10:31. [PMID: 19154572 PMCID: PMC2633352 DOI: 10.1186/1471-2164-10-31] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2008] [Accepted: 01/20/2009] [Indexed: 11/17/2022] Open
Abstract
Background Avian coccidiosis is a major parasitic disease of poultry, causing severe economical loss to poultry production by affecting growth and feed efficiency of infected birds. Current control strategies using mainly drugs and more recently vaccination are showing drawbacks and alternative strategies are needed. Using genetic resistance that would limit the negative and very costly effects of the disease would be highly relevant. The purpose of this work was to detect for the first time QTL for disease resistance traits to Eimeria tenella in chicken by performing a genome scan in an F2 cross issued from a resistant Fayoumi line and a susceptible Leghorn line. Results The QTL analysis detected 21 chromosome-wide significant QTL for the different traits related to disease resistance (body weight growth, plasma coloration, hematocrit, rectal temperature and lesion) on 6 chromosomes. Out of these, a genome-wide very significant QTL for body weight growth was found on GGA1, five genome-wide significant QTL for body weight growth, plasma coloration and hematocrit and one for plasma coloration were found on GGA1 and GGA6, respectively. Two genome-wide suggestive QTL for plasma coloration and rectal temperature were found on GGA1 and GGA2, respectively. Other chromosme-wide significant QTL were identified on GGA2, GGA3, GGA6, GGA15 and GGA23. Parent-of-origin effects were found for QTL for body weight growth and plasma coloration on GGA1 and GGA3. Several QTL for different resistance phenotypes were identified as co-localized on the same location. Conclusion Using an F2 cross from resistant and susceptible chicken lines proved to be a successful strategy to identify QTL for different resistance traits to Eimeria tenella, opening the way for further gene identification and underlying mechanisms and hopefully possibilities for new breeding strategies for resistance to coccidiosis in the chicken. From the QTL regions identified, several candidate genes and relevant pathways linked to innate immune and inflammatory responses were suggested. These results will be combined with functional genomics approaches on the same lines to provide positional candidate genes for resistance loci for coccidiosis. Results suggested also for further analysis, models tackling the complexity of the genetic architecture of these correlated disease resistance traits including potential epistatic effects.
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21
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Abstract
Natural killer (NK) activity has been examined in birds for over 30 years, but evidence that avian NK activity plays crucial roles in disease is only suggestive. In chickens, NK activity is mediated by TCR0 cells in the intestinal epithelium, but elsewhere subsets of alphabeta and gammadelta T cells (NKT cells) may be more important. There are few lectin-like NK receptor genes, located in the genomic region syntenic with the natural killer complex (NKC) as well as the major histocompatibility complex (MHC). In contrast, a huge number of Ig-like receptor genes are located in a region syntenic with the leukocyte receptor complex (LRC).
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22
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McGraw KJ, Tourville EA, Butler MW. A quantitative comparison of the commonly used methods for extracting carotenoids from avian plasma. Behav Ecol Sociobiol 2008. [DOI: 10.1007/s00265-008-0622-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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23
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Brown MG, Scalzo AA. NK gene complex dynamics and selection for NK cell receptors. Semin Immunol 2008; 20:361-8. [PMID: 18640056 DOI: 10.1016/j.smim.2008.06.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2008] [Accepted: 06/06/2008] [Indexed: 01/06/2023]
Abstract
Natural killer (NK) cells play important roles in innate defense against infectious agents particularly viruses and also tumors. They mediate their effects through direct cytolysis, release of cytokines and regulation of subsequent adaptive immune responses. NK cells are equipped with sophisticated arrays of inhibitory and activation receptors that regulate their function. In this review we illustrate some of the major evolutionary relationships between NK cell receptors among different animal species and what some of the major mechanisms are that give rise to this diversity in receptor families, including the potential roles of pathogens such as viruses in driving receptor evolution.
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Affiliation(s)
- Michael G Brown
- Center for Immunity, Inflammation and Regenerative Medicine, Department of Medicine, University of Virginia, Charlottesville, VA 22908, United States
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24
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Lillehoj HS, Kim CH, Keeler CL, Zhang S. Immunogenomic approaches to study host immunity to enteric pathogens. Poult Sci 2007; 86:1491-500. [PMID: 17575200 DOI: 10.1093/ps/86.7.1491] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
With increasing consumer demands for safe poultry products, effective control of disease-causing pathogens is becoming a major challenge to the poultry industry. Many chicken pathogens enter the host through the gastrointestinal tract, and over the past few decades, in-feed antibiotics and active vaccination have been the 2 main mechanisms of disease control. However, increasing public concerns are prompting government regulations on the use of growth-promoting drugs in animal production, and the ability of current vaccines to protect against emerging hypervirulent strains of pathogens is becoming an issue. Therefore, there is a need to develop alternative control strategies against poultry pathogens of economic importance as well as to carry out basic research to enhance understanding of host-pathogen interactions at local sites of infection. Effective control strategies against pathogens can only be accomplished by comprehensive analysis of the basic immunobiology of host-pathogen interactions. Recent sequencing of the poultry genome and the availability of several tissue-specific cDNA microarrays are facilitating the rapid application of functional immunogenomic technologies to poultry disease research. Studies using functional genomic, immunology, and bioinformatic approaches have provided novel insights into disease processes and protective immunity to chicken pathogens. In this review, we summarize recent published literature concerning the host response to Eimeria and Salmonella infections with emphasis on our studies using immunogenomic tools to investigate and characterize the mechanisms of avian immunity to these mucosal pathogens. The results clearly indicate that this immunogenomic approach will lead to increased understanding of immune responses to infectious agents that will enable the development of effective prevention strategies against mucosal pathogens.
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Affiliation(s)
- H S Lillehoj
- Animal Parasitic Diseases Laboratory, Animal and Natural Resources Institute, Agricultural Research Service, USDA, Beltsville, MD 20705, USA.
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25
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Chiang HI, Zhou H, Raudsepp T, Jesudhasan PR, Zhu JJ. Chicken CD69 and CD94/NKG2-like genes in a chromosomal region syntenic to mammalian natural killer gene complex. Immunogenetics 2007; 59:603-11. [PMID: 17505822 DOI: 10.1007/s00251-007-0220-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2006] [Accepted: 03/26/2007] [Indexed: 10/23/2022]
Abstract
In mammals, natural killer (NK) cell C-type lectin receptors were encoded in a gene cluster called natural killer gene complex (NKC). The NKC is not reported in chicken yet. Instead, NK receptor genes were found in the major histocompatibility complex. In this study, two novel chicken C-type lectin-like receptor genes were identified in a region on chromosome 1 that is syntenic to mammalian NKC region. The chromosomal locations were validated with fluorescent in situ hybridization. Based on 3D structure modeling, sequence homology, chromosomal location, and phylogenetic analysis, one receptor is the orthologue of mammalian cluster of differentiation 69 (CD69), and the other is highly homologous to CD94 and NKG2. Like CD94/NKG2 gene found in teleostean fishes, chicken CD94/NKG2 has the features of both human CD94 and NKG2A. Unlike mammalian NKC, these two chicken C-type lectin receptors are not closely linked but separated by 42 million base pairs according to the chicken draft genome sequence. The arrangement of several other genes that are located outside the mammalian NKC is conserved among chicken, human, and mouse. The chicken NK C-type lectin-like receptors in the NKC syntenic region indicate that this chromosomal region existed before the divergence between mammals and aves.
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MESH Headings
- Amino Acid Sequence
- Animals
- Antigens, CD/genetics
- Antigens, Differentiation, T-Lymphocyte/genetics
- Cattle
- Chickens/genetics
- Chromosomal Proteins, Non-Histone/genetics
- Evolution, Molecular
- Humans
- Killer Cells, Natural/immunology
- Killer Cells, Natural/metabolism
- Lectins, C-Type
- Mice
- Molecular Sequence Data
- NK Cell Lectin-Like Receptor Subfamily C
- NK Cell Lectin-Like Receptor Subfamily D/genetics
- Rats
- Receptors, Immunologic/genetics
- Receptors, Natural Killer Cell
- Sequence Homology, Amino Acid
- Synteny/genetics
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Affiliation(s)
- Hsin-I Chiang
- Department of Poultry Science, Texas A & M University, College Station, TX 77843, USA
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26
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Abasht B, Dekkers JCM, Lamont SJ. Review of Quantitative Trait Loci Identified in the Chicken. Poult Sci 2006; 85:2079-96. [PMID: 17135661 DOI: 10.1093/ps/85.12.2079] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Methods for mapping QTL are actively used in the chicken to identify chromosomal regions contributing to variation in traits related to growth, disease resistance, egg production, behavior, and metabolic parameters. However, higher-resolution mapping and better knowledge of the genetic architecture underlying QTL are needed for successful application of this information into breeding programs. Therefore, this paper summarizes and integrates original, primary QTL studies in the chicken to identify basic information on the genetic architecture of quantitative traits in chickens. The results of this review show several instances of consensus of QTL locations for similar traits from independent studies. Furthermore, the consensus of QTL location for different traits and evidence for QTL with parent-of-origin effect, transgressive alleles, epistatic QTL, and QTL x sex interaction in chicken are presented and discussed. This information can be helpful in identifying genes or mutations underlying the QTL and in the application of genomic information in marker-assisted breeding programs.
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Affiliation(s)
- B Abasht
- Department of Animal Science, Iowa State University, Ames 50011, USA
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27
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Kim ES, Hong YH, Min W, Lillehoj HS. Fine-Mapping of Coccidia-Resistant Quantitative Trait Loci in Chickens. Poult Sci 2006; 85:2028-30. [PMID: 17032840 DOI: 10.1093/ps/85.11.2028] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Two commercial, pure broiler lines with different susceptibility to coccidiosis were used to fine-map QTL associated with the previously identified marker LEI0101, located at 259 cM on chromosome 1 and shown to be significantly associated with disease resistance. Eight additional microsatellite markers linked to LEI0101 were used for genotyping of F(1) parents and F(2) offspring (n = 314), and their associations with oocyst shedding, as a marker of disease resistance, were determined in birds experimentally infected with Eimeria maxima. Single-point analysis of 4 families showed that logarithm of odds (LOD) scores at all marker loci were > 0.5, with the exception of marker LEI0071, located at 242 cM (LOD score = 2.45). Multipoint analysis showed a maximum LOD score between LEI0071 and LEI0101 at 254 cM (LOD score = 3.74). Although the LEI0071 marker was mapped near LEI0101 by linkage analysis, the physical location of LEI0071 was not identified. Further studies to determine the physical locations of these and other markers will allow additional application association mapping techniques using single nucleotide polymorphism markers.
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Affiliation(s)
- E-S Kim
- Department of Animal Sciences, University of Wisconsin-Madison, 53706, USA
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28
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Zhou H, Deeb N, Evock-Clover CM, Ashwell CM, Lamont SJ. Genome-Wide Linkage Analysis to Identify Chromosomal Regions Affecting Phenotypic Traits in the Chicken. I. Growth and Average Daily Gain. Poult Sci 2006; 85:1700-11. [PMID: 17012159 DOI: 10.1093/ps/85.10.1700] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A genome scan was used to detect chromosomal regions and QTL that control quantitative traits of economic importance in chickens. Two unique F(2) crosses generated from a commercial broiler male line and 2 genetically distinct inbred lines (Leghorn and Fayoumi) were used to identify QTL affecting BW and daily average gain traits in chickens. Body weight at 2, 4, 6, and 8 wk was measured in the 2 F(2) crosses. Birds were genotyped for 269 microsatellite markers across the entire genome. Linkage distance among microsatellite markers was estimated by the CRIMAP program. The program QTL Express was used for QTL detection. Significance levels were obtained using the permutation test. For the 8 traits, a total of 18 and 13 significant QTL were detected at a 1% chromosome-wise significance level, of which 17 and 10 were significant at the 5% genome-wise level for the broiler-Leghorn cross and broiler-Fayoumi cross, respectively. Highly correlated growth traits showed similar QTL profiles within each cross but different QTL profiles between the 2 crosses. Most QTL for growth traits in the current study were detected in Gga 1, 2, 4, 7, and 14 for the broiler-Leghorn cross and Gga 1, 2, 4, 5, 8, and 13 for the broiler-Fayoumi cross. Potential candidate genes within the QTL region for growth traits at 1% chromosome-wise significance level were discussed. The results in the current study lay the foundations for fine mapping these traits in the advanced intercross lines and provide a start point for identification causative genes responsible for growth traits in chickens.
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Affiliation(s)
- H Zhou
- Department of Animal Science, Iowa State University, Ames 50011, USA
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29
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Schreiweis MA, Hester PY, Settar P, Moody DE. Identification of quantitative trait loci associated with egg quality, egg production, and body weight in an F2 resource population of chickens1. Anim Genet 2006; 37:106-12. [PMID: 16573524 DOI: 10.1111/j.1365-2052.2005.01394.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Egg production and egg quality are complex sex-limited traits that may benefit from the implementation of marker-assisted selection. The primary objective of the current study was to identify quantitative trait loci (QTL) associated with egg traits, egg production, and body weight in a chicken resource population. Layer (White Leghorn hens) and broiler (Cobb-Cobb roosters) lines were crossed to generate an F2 population of 508 hens over seven hatches. Phenotypes for 29 traits (weekly body weight from hatch to 6 weeks, egg traits including egg, albumen, yolk, and shell weight, shell thickness, shell puncture score, percentage of shell, and egg shell colour at 35 and 55 weeks of age, as well as egg production between 16 and 55 weeks of age) were measured in hens of the resource population. Genotypes of 120 microsatellite markers on 28 autosomal groups were determined, and interval mapping was conducted to identify putative QTL. Eleven QTL tests representing two regions on chromosomes 2 and 4 surpassed the 5% genome-wise significance threshold. These QTL influenced egg colour, egg and albumen weight, percent shell, body weight, and egg production. The chromosome 4 QTL region is consistent with multiple QTL studies that define chromosome 4 as a critical region significantly associated with a variety of traits across multiple resource populations. An additional 64 QTL tests surpassed the 5% chromosome-wise significance threshold.
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Affiliation(s)
- M A Schreiweis
- Department of Animal Sciences, Purdue University, West Lafayette, IN 47907, USA
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30
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de Koning DJ, Carlborg O, Haley CS. The genetic dissection of immune response using gene-expression studies and genome mapping. Vet Immunol Immunopathol 2005; 105:343-52. [PMID: 15808311 DOI: 10.1016/j.vetimm.2005.02.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Functional genomics has been applied to the genetic dissection of immune response in different ways: (1) experimental crosses between lines that differ in their (non-) specific immune response have been used to detect quantitative trait loci (QTL) underlying these differences. (2) The measurement of gene expression levels for thousands of genes using microarrays or oligonucleotide chips to identify differential expression with regard to antigen challenge: (a) before and after infection, (b) resistant versus susceptible lines, or (c) combinations of both. Interpretation of QTL results is hampered by the fact that confidence regions of the QTL are large and can contain hundreds of potential candidate genes for the QTL. At the same time, the microarray experiments tend to show large numbers of differentially expressed genes without identifying the relationships between these genes. In the recently proposed 'genetical genomics' framework, members of a segregating population are characterised for genome-wide molecular markers and for gene expression levels. This facilitates the mapping of expression-QTL (eQTL): loci in the genome that control the expression of genes. Initial applications of this approach are critically reviewed and potential applications of this approach with regard to immune response are presented.
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31
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Dalloul RA, Lillehoj HS. Recent advances in immunomodulation and vaccination strategies against coccidiosis. Avian Dis 2005; 49:1-8. [PMID: 15839405 DOI: 10.1637/7306-11150r] [Citation(s) in RCA: 150] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Coccidiosis is a ubiquitous intestinal protozoan infection of poultry seriously impairing the growth and feed utilization of infected animals. Conventional disease control strategies rely heavily on chemoprophylaxis, which is a tremendous cost to the industry. Existing vaccines consist of live virulent or attenuated Eimeria strains with limited scope of protection against an ever-evolving and widespread pathogen. The continual emergence of drug-resistant strains of Eimeria, coupled with the increasing regulations and bans on the use of anticoccidial drugs in commercial poultry production, urges the need for novel approaches and alternative control strategies. Because of the complexity of the host immunity and the parasite life cycle, a comprehensive understanding of host-parasite interactions and protective immune mechanisms becomes necessary for successful prevention and control practices. Recent progress in functional genomics technology would facilitate the identification and characterization of host genes involved in immune responses as well as parasite genes and proteins that elicit protective host responses. This study reviews recent coccidiosis research and provides information on host immunity, immunomodulation, and the latest advances in live and recombinant vaccine development against coccidiosis. Such information will help magnify our understanding of host-parasite biology and mucosal immunology, and we hope it will lead to comprehensive designs of nutritional interventions and vaccination strategies for coccidiosis.
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Affiliation(s)
- Rami A Dalloul
- Animal Parasitic Diseases Laboratory, Animal and Natural Resources Institute, USDA-ARS, BARC-East, Building 1040, Beltsville, MD 20705, USA
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32
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Siwek M, Cornelissen SJB, Buitenhuis AJ, Nieuwland MGB, Bovenhuis H, Crooijmans RPMA, Groenen MAM, Parmentier HK, van der Poel JJ. Quantitative trait loci for body weight in layers differ from quantitative trait loci specific for antibody responses to sheep red blood cells. Poult Sci 2004; 83:853-9. [PMID: 15206609 DOI: 10.1093/ps/83.6.853] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Quantitative trait loci for BW at 4, 6, 8, 12, and 18 wk of age were detected in an experimental F2 cross of layers divergently selected for primary antibody response to SRBC. A negative phenotypic correlation between levels of antibody titers and BW, was reported earlier within founder lines. The entire experimental population was genotyped with 174 microsatellite markers equally distributed over the genome. Two genetic models were applied in the QTL analysis: a half-sib model and a line-cross model, both using the regression interval method. In the half-sib model, 3 QTL for BW at 4 wk of age on chromosomes GGA2, GGA3, and GGA9 were detected. For BW at 6 wk of age, 3 QTL were detected on GGA2, GGA3, and GGA6. For BW at 8 wk of age, a QTL was detected on GGA7, and for BW at 12 and 18 wk of age, a QTL was detected on GGAZ. With the line-cross analysis model, one QTL on GGA7 for BW at 4 wk of age was detected. Two QTL were detected on GGA3 and GGA7 for BW at 6 wk of age, and one on GGA3 was detected for BW for 8 and 12 wk of age. For BW at 18 wk of age, there were no QTL under the line-cross analysis model. The present data suggest that 1) a different set of genes affects the early and the late growth, and 2) genes selected to humoral immune responsiveness are different from genes underlying growth.
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Affiliation(s)
- M Siwek
- Animal Breeding and Genetics Group, Wageningen Institute of Animal Sciences, Wageningen University, PO Box 338, 6700 AH Wageningen, The Netherlands.
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Jennen DGJ, Vereijken ALJ, Bovenhuis H, Crooijmans RPMA, Veenendaal A, van der Poel JJ, Groenen MAM. Detection and localization of quantitative trait loci affecting fatness in broilers. Poult Sci 2004; 83:295-301. [PMID: 15049477 DOI: 10.1093/ps/83.3.295] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
A cross between 2 genetically different outcross broiler dam lines, originating from the White Plymouth Rock breed, was used to produce a large 3-generation broiler population. This population was used to detect and localize QTL affecting fatness in chicken. Twenty full-sib birds in generation 1 and 456 full-sib birds in generation 2 were typed for microsatellite markers, and phenotypic observations were collected for 3 groups of generation 3 birds (approximately 1,800 birds per group). Body weight, abdominal fat weight, and percentage abdominal fat was recorded at the age of 7, 9, and 10 wk. To study the presence of QTL, an across-family weighted regression interval mapping approach was used in a full-sib QTL analysis. Genotypes from 410 markers mapped on 25 chromosomes were available. For the 3 traits, 26 QTL were found for 18 regions on 12 chromosomes. Two genomewise significant QTL (P < 0.05) were detected, one for percentage abdominal fat at the age of 10 wk on chicken chromosome 1 at 241 cM (MCW0058 to MCW0101) with a test statistic of 2.75 and the other for BW at the age of 10 wk on chicken chromosome 13 at 9 cM (MCW0322 to MCW0110) with a test statistic of 2.77. Significance levels were obtained using the permutation test. Multiple suggestive QTL were found on chromosomes 1, 2, 4, 13, 15, and 18, whereas chromosomes 3, 7, 10, 11, 14, and 27 had a single suggestive QTL.
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Affiliation(s)
- D G J Jennen
- Wageningen Institute of Animal Sciences, Animal Breeding and Genetics Group, Wageningen University, Marijkeweg 40, 6709 PG Wageningen, The Netherlands.
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Abstract
The current chicken genetic map contains at least 1,965 loci within 50 linkage groups, and it covers about 4,000 cM. About 235 of these loci have homology with known human or mammalian genes. The remaining loci are anonymous molecular DNA markers, including microsatellites, amplified fragment length polymorphism (AFLP), randomly amplified polymorphic DNA (RAPD), CR1 elements, and others. A third generation genetic map for human uses single nucleotide polymorphisms (SNP), which have allowed the mapping of complex traits by linkage disequilibrium. One advantage of SNP is that they are usually linked to the gene of interest, and association of the SNP with traits of economic importance can be analyzed using candidate gene approaches. With the tremendous advancements in characterizing chicken expressed sequence tags (EST), the identification of genetic polymorphisms such as SNP in chicken genes has become a reality. Our laboratory has undertaken an in silico analysis of the chicken EST at the University of Delaware by using a Phred/Phrap/Polyphred/Consed pipeline to identify candidate chicken SNP. Initial scanning of 23,427 chicken EST identified a total of 1,209 candidate SNP, with at least 182 non-synonymous SNP that result in an amino acid change observed. Validation of these candidate chicken SNP is ongoing. Placement of the SNP on the chicken genetic map will enhance marker density, thus allowing for mapping of complex traits through linkage analysis and linkage disequilibrium. Application of SNP to identify disease resistance genes in chickens is of special interest to our laboratory, especially in regards to Marek's disease and coccidiosis.
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Affiliation(s)
- M G Emara
- Department of Animal and Food Sciences, University of Delaware, Newark, Delaware 19717, USA.
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35
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Host Immunity and Vaccine Development to Coccidia and Salmonella Infections in Chickens. J Poult Sci 2003. [DOI: 10.2141/jpsa.40.151] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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