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1.
Anaerobe ; 48: 224-231, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28928035

ABSTRACT

Clostridium difficile is an anaerobic spore-forming bacillus that usually causes gastrointestinal disorders in man and other animal species. Most of the strains isolated from animals are toxigenic being the virulent ribotype (RT) 078 predominant in several animal species. Although C. difficile is pathogenic to both humans and animals, there is no direct evidence of zoonosis. Deep genome sequencing provides sufficient resolution to analyse which strains found in animals might be related to human pathogens. So far, there are only a few fully sequenced genomes of C. difficile strains isolated from domestic and wild animals. Using Illumina technology, we have sequenced the genome of three isolates; a strain isolated from the vagina of a sow (5754), one from rat (Rattus spp) intestinal content (RC10) and a third one isolated from environmental rat faeces (RF17). Both, rat and rat faeces were sampled in fattening pig farms. Our study reveals a close genetic relationship of two of these isolates with the virulent strain M120 (RT078) isolated from a human patient. The analysis of the sequences has revealed the presence of antibiotic resistance genes, mobile elements, including the transposon linked with virulence Tn6164, and the similarity of virulence factors between these isolates and human strains. This is the first study focused on the sequencing of C. difficile genomes obtained from wild animals like rats, which can be considered as potential reservoirs for humans and other animal species. This study can help to understand the genome composition and epidemiology of this bacterium species.


Subject(s)
Clostridioides difficile/classification , Clostridioides difficile/genetics , Genome, Bacterial , Genomics , Animals , Anti-Bacterial Agents/pharmacology , Clostridioides difficile/drug effects , Clostridium Infections/veterinary , Microbial Sensitivity Tests , Phylogeny , Polymerase Chain Reaction , Ribotyping , Swine , Swine Diseases/microbiology
2.
Anim Genet ; 48(3): 315-329, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28094449

ABSTRACT

Biodiversity studies are more efficient when large numbers of breeds belonging to several countries are involved, as they allow for an in-depth analysis of the within- and between-breed components of genetic diversity. A set of 21 microsatellites was used to investigate the genetic composition of 24 Creole goat breeds (910 animals) from 10 countries to estimate levels of genetic variability, infer population structure and understand genetic relationships among populations across the American continent. Three commercial transboundary breeds were included in the analyses to investigate admixture with Creole goats. Overall, the genetic diversity of Creole populations (mean number of alleles = 5.82 ± 1.14, observed heterozygosity = 0.585 ± 0.074) was moderate and slightly lower than what was detected in other studies with breeds from other regions. The Bayesian clustering analysis without prior information on source populations identified 22 breed clusters. Three groups comprised more than one population, namely from Brazil (Azul and Graúna; Moxotó and Repartida) and Argentina (Long and shorthair Chilluda, Pampeana Colorada and Angora-type goat). Substructure was found in Criolla Paraguaya. When prior information on sample origin was considered, 92% of the individuals were assigned to the source population (threshold q ≥ 0.700). Creole breeds are well-differentiated entities (mean coefficient of genetic differentiation = 0.111 ± 0.048, with the exception of isolated island populations). Dilution from admixture with commercial transboundary breeds appears to be negligible. Significant levels of inbreeding were detected (inbreeding coefficient > 0 in most Creole goat populations, P < 0.05). Our results provide a broad perspective on the extant genetic diversity of Creole goats, however further studies are needed to understand whether the observed geographical patterns of population structure may reflect the mode of goat colonization in the Americas.


Subject(s)
Genetic Variation , Genetics, Population , Goats/genetics , Alleles , Americas , Animals , Bayes Theorem , Breeding , Gene Frequency , Genetic Markers , Genotype , Geography , Heterozygote , Microsatellite Repeats , Sequence Analysis, DNA
3.
J Appl Microbiol ; 122(2): 462-472, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27990723

ABSTRACT

AIMS: To determine the presence of Clostridium difficile on fattening pig farms in north-eastern Spain. METHODS AND RESULTS: Twenty-seven farms were sampled. Pools of pig faecal samples (n = 210), samples of intestinal content from common farm pest species (n = 95) and environment-related samples (n = 93) were collected. Isolates were tested for toxin genes of C. difficile, and typed by PCR-ribotyping and toxinotyping. The minimal inhibitory concentrations of six antimicrobial agents were determined using Etest. Thirty-four isolates were obtained from 12 farms, and 30 (88·2%) had toxin genes. Seven ribotypes were identified. Ribotype 078 and its variant 126 were predominant (52·9%). The same ribotypes were isolated from different animal species on the same farm. None of the isolates were resistant to metronidazole or vancomycin. CONCLUSIONS: Clostridium difficile was common within the pig farm environment. Most of the positive samples came from pest species or were pest-related environmental samples. SIGNIFICANCE AND IMPACT OF THE STUDY: Pest species were colonized with toxigenic and antimicrobial-resistant C. difficile strains of the same ribotypes that are found in humans and pigs. Rodents and pigeons may transmit toxigenic and antimicrobial-resistant C. difficile strains that are of the same ribotypes as those occuring in humans.


Subject(s)
Anti-Bacterial Agents/pharmacology , Clostridioides difficile/isolation & purification , Clostridium Infections/transmission , Feces/microbiology , Animals , Animals, Wild , Clostridioides difficile/classification , Clostridium Infections/veterinary , Farms , Humans , Metronidazole/pharmacology , Microbial Sensitivity Tests , Polymerase Chain Reaction , Ribotyping , Spain , Sus scrofa
4.
BMC Vet Res ; 12: 65, 2016 Mar 31.
Article in English | MEDLINE | ID: mdl-27029614

ABSTRACT

BACKGROUND: Mesenchymal stem cells (MSCs) transplantation has become a promising therapeutic choice for musculoskeletal injuries. Joint-related disorders are highly prevalent in horses. Therefore, these animals are considered as suitable models for testing MSC-based therapies for these diseases. The aim of this study was to investigate the clinical and inflammatory responses to intra-articular single and repeat dose administration of autologous or of pooled allogeneic MSCs in healthy equine healthy joints. Six horses were intra-articularly injected with a single autologous dose of bone marrow derived MSCs (BM-MSCs) and two separate doses of allogeneic BM-MSCs pooled from several donors. All contralateral joints were injected with Lactated Ringer's Solution (LRS) as the control vehicle. Signs of synovitis and lameness were evaluated at days 0, 1, 2, 3, 5 and 10 after injection. Total protein (TP), white blood cell count (WBC) and neutrophil count (NC) in synovial fluid were also measured at the same time-points. RESULTS: A mild synovial effusion without associated lameness was observed after all BM-MSCs injections. The second allogeneic injection caused the lowest signs of synovitis. Local temperature slightly increased after all BM-MSCs treatments compared to the controls. TP, WBC and NC in synovial fluids also increased during days 1 to 5 after all BM-MSCs injections. Both, clinical and synovial parameters were progressively normalized and by day 10 post-inoculation appeared indistinguishable from controls. CONCLUSIONS: Intra-articular administration of an allogeneic pool of BM-MSCs represents a safe therapeutic strategy to enhance MSCs availability. Importantly, the absence of hypersensitivity response to the second allogeneic BM-MSCs injection validates the use of repeat dose treatments to potentiate the therapeutic benefit of these cells. These results notably contribute to the development of stem cell based therapies for equine and human joint diseases.


Subject(s)
Injections, Intra-Articular/standards , Joint Diseases/therapy , Mesenchymal Stem Cell Transplantation/standards , Animals , Disease Models, Animal , Horses , Injections, Intra-Articular/adverse effects , Lameness, Animal/etiology , Leukocyte Count , Neutrophils/physiology , Random Allocation , Reproducibility of Results , Synovial Fluid/cytology , Synovitis/etiology
5.
Vet Immunol Immunopathol ; 171: 57-65, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26964718

ABSTRACT

Mesenchymal stem cells (MSCs) are being investigated for the treatment of equine joint diseases because of their regenerative potential. Recently, the focus mainly has addressed to their immunomodulatory capacities. Inflammation plays a central role in joint pathologies, since the release of proinflammatory mediators to the synovial fluid (SF) leads to the activation of enzymatic degradation of the cartilage. MSCs can modulate the local immune environment through direct or paracrine interaction with immune cells, suppressing their proliferation and re-addressing their functions. Proinflammatory molecules can induce MSC immunoregulatory potential, but they could also increase the expression of immunogenic molecules. Studying the effect of inflammatory environment on MSC immunomodulation and immunogenicity profiles is mandatory to improve cellular therapies. The aim of this study was to analyse the response of equine bone marrow MSCs (eBM-MSCs) to three inflammatory conditions. Equine BM-MSCs from three animals were exposed to: (a) 20% allogeneic inflammatory SF (SF); (b) 50 ng/ml of TNFα and IFNγ (CK50) and (c) 20 ng/ml of TNFα and IFNγ (CK20). After 72 h of exposure, expression of immunogenic and immunomodulation-related molecules, including cell-to-cell contact and paracrine signalling molecules, were analysed by RT-qPCR and flow cytometry. The gene expression of adhesion molecules was upregulated whereas MSC migration-related genes were downregulated by all inflammatory conditions tested. CK culture conditions significantly upregulated the expression of COX-2, iNOS, IDO and IL-6. MHC-I gene expression was upregulated by all conditions, whereas MHC-II was upregulated only after CK priming. The expression of CD40 did not significantly change, whereas the ligand, CD40L, was downregulated in CK conditions. Flow cytometry showed an increase in the percentage of positive cells and mean fluorescence intensity (MFI) of the MHC-I and MHC-II molecules at CK50 conditions, supporting the gene expression results. These outcomes reinforce the change of the immunophenotype of the eBM-MSCs according to the surrounding conditions. Inflammatory synovial environment did not lead to significant changes, so the environment found by eBM-MSCs when they are intraarticular administered may not be enough to activate their immunomodulatory potential. CK priming at tested doses enhances the immunoregulatory profile of eBM-MSCs, which may promote a therapeutic benefit. Even if CK priming induced an upregulation of MHC expression, costimulatory molecule expression however was not upregulated, suggesting that immunogenicity might not be increased. This study provides a better understanding about the behaviour of eBM-MSCs inside the inflamed joint and constitutes a first step to improve MSC-based therapies for equine joint diseases.


Subject(s)
Bone Marrow Cells/immunology , Horse Diseases/immunology , Immunomodulation , Inflammation/veterinary , Joint Diseases/veterinary , Mesenchymal Stem Cells/immunology , Animals , Cells, Cultured , Horses , Inflammation/immunology , Inflammation Mediators/immunology , Interferon-gamma/immunology , Joint Diseases/immunology , Joints/immunology , Male , Synovial Fluid/immunology , Tumor Necrosis Factor-alpha/immunology
6.
J Comp Pathol ; 152(2-3): 269-73, 2015.
Article in English | MEDLINE | ID: mdl-25678424

ABSTRACT

Clinical and pathological studies in European badgers (Meles meles) are limited. Badgers play a significant role in the epidemiology of bovine tuberculosis (TB) in some countries and an accurate diagnosis is needed for this infection. However, the lesions of bovine TB are similar to those associated with other pathogens, making pathological diagnosis difficult. In the present study, Streptococcus halichoeri was isolated from a European badger with pyogranulomatous pleuropneumonia and suspected of having tuberculosis. TB and other pathogens able to induce similar lesions were ruled out. Comparative 16S rRNA and rpoB gene sequencing studies showed an identity of 99.51% and 98.28%, respectively, with S. halichoeri. This report represents the third description of this bacterium and the first in an animal species other than the grey seal (Halichoerus grypus). It also shows that S. halichoeri can be associated with a pathological process characterized by granulomatous inflammation and resembling tuberculosis.


Subject(s)
Mustelidae/microbiology , Phylogeny , Pleuropneumonia/veterinary , Streptococcal Infections/veterinary , Streptococcus/genetics , Animals , Female , Granuloma/microbiology , Granuloma/pathology , Granuloma/veterinary , Pleuropneumonia/microbiology , Pleuropneumonia/pathology , RNA, Ribosomal, 16S/analysis , Streptococcal Infections/pathology , Streptococcus/isolation & purification
7.
Zoonoses Public Health ; 62(3): 165-78, 2015 May.
Article in English | MEDLINE | ID: mdl-24854140

ABSTRACT

Scrapie and bovine spongiform encephalopathy are fatal neurodegenerative diseases caused by the accumulation of a misfolded protein (PrP(res)), the pathological form of the cellular prion protein (PrP(C)). For the last decades, prion research has greatly progressed, but many questions need to be solved about prion replication mechanisms, cell toxicity, differences in genetic susceptibility, species barrier or the nature of prion strains. These studies can be developed in murine models of transmissible spongiform encephalopathies, although development of cell models for prion replication and sample titration could reduce economic and timing costs and also serve for basic research and treatment testing. Some murine cell lines can replicate scrapie strains previously adapted in mice and very few show the toxic effects of prion accumulation. Brain cell primary cultures can be more accurate models but are difficult to develop in naturally susceptible species like humans or domestic ruminants. Stem cells can be differentiated into neuron-like cells and be infected by prions. However, the use of embryo stem cells causes ethical problems in humans. Mesenchymal stem cells (MSCs) can be isolated from many adult tissues, including bone marrow, adipose tissue or even peripheral blood. These cells differentiate into neuronal cells, express PrP(C) and can be infected by prions in vitro. In addition, in the last years, these cells are being used to develop therapies for many diseases, including neurodegenerative diseases. We review here the use of cell models in prion research with a special interest in the potential use of MSCs.


Subject(s)
Cattle Diseases/pathology , Mesenchymal Stem Cells/pathology , Prion Diseases/pathology , Prions/physiology , Sheep Diseases/pathology , Animals , Cattle , Humans , PrPSc Proteins/pathogenicity , Prions/pathogenicity , Research , Sheep
8.
J Anim Breed Genet ; 131(1): 11-8, 2014 Feb.
Article in English | MEDLINE | ID: mdl-25099784

ABSTRACT

The Casta Navarra lineage was one of the populations used to establish the fighting bull (FB) breed, and it has also been reproductively isolated from the others FBs. A total of 1284 individuals from two generations of 16 Casta Navarra herds were sampled to analyse their diversity, their genetic structure and the ability of 28 microsatellite markers to assign individuals to closely related populations. These animals were compared with closely related phylogenetic (FB) or geographical (Pirenaica and Monchina) populations. Hardy-Weinberg equilibrium analysis showed that 82% of the loci had a significant heterozygote deficit as a consequence of the Wahlund effect. The average proportion of genetic variation explained by farm differences was 9% by Wright's FST index. A phylogenetic tree constructed with a neighbour-joining method based on Reynolds genetic distances and a Bayesian Markov chain Monte Carlo clustering approach revealed clear differences between farm groups that generally corresponded to historical information and could unambiguously differentiate Casta Navarra cattle from the other populations. The percentage of animals correctly assigned to the Casta Navarra population was 91.78% for a q threshold of >0.9. Admixture was only detected in 4.45% (q < 0.8) of the cattle. These results are relevant for the maintenance and development of diversity and conservation in the Casta Navarra population.


Subject(s)
Breeding , Genetic Variation , Microsatellite Repeats/genetics , Phylogeny , Animals , Bayes Theorem , Cattle , Genetics, Population , Heterozygote
9.
J Anim Breed Genet ; 130(1): 79-86, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23317068

ABSTRACT

Conservation and improvement strategies in farm animals should be based on a combination of genetic and phenotypic characteristics. Genotype data from 30 microsatellites were used to assess the genetic diversity and relationships among five Cuban cattle breeds (Siboney de Cuba, Criollo Cubano, Cebú Cubano, Mambí de Cuba and Taíno de Cuba). All microsatellite markers were highly polymorphic in all the breeds. The expected heterozygosity ranged from 0.67 ± 0.02 in the Taíno de Cuba breed to 0.75 ± 0.02 in the Mambí de Cuba breed, and the observed heterozygosity ranged from 0.66 ± 0.03 in the Cebú Cubano breed to 0.73 ± 0.02 in the Siboney de Cuba breed. The genetic differentiation between the breeds was significant (p < 0.01) based on the infinitesimal model (F(ST)). The exact test for Hardy-Weinberg equilibrium within breeds showed a significant deviation in each breed (p < 0.0003) for one or more loci. The genetic distance and structure analysis showed that a significant amount of genetic variation is maintained in the local cattle population and that all breeds studied could be considered genetically distinct. The Siboney de Cuba and Mambí de Cuba breeds seem to be the most genetically related among the studied five breeds.


Subject(s)
Breeding , Genetic Variation , Microsatellite Repeats/genetics , Animals , Cattle , Conservation of Natural Resources , Cuba , Heterozygote , Phylogeny
10.
J Anim Sci ; 90(10): 3325-36, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22665633

ABSTRACT

An mRNA expression study has been performed in 20- to 25-min postmortem-obtained samples from Longissimus dorsi muscle of 59 Duroc × Landrace/ Large White (LD/LW) pigs to search for gene sequences related to meat quality (pH(24), pH(45), "Lab" color coordinates, curing yield, and exudation at 3 different times) or meat composition [intramuscular fat, content of several fatty acids (C16:0, C18:0, C18:1, and C18:2), ratio of saturated, monounsaturated, and polyunsaturated fatty acids, and protein and humidity contents] traits to find targets for selection. Gene ontology analysis, biological pathway, and gene network studies all show that many more differentially expressed genes (506 vs. 279) are related to meat quality (Group P or perimortem characters) than to meat composition traits (Group L or whole life traits). The difference between the number of gene ontology terms annotated, biological pathways, and gene networks in groups P and L is notable due to the differences in the complexity of the "generation process" of P-traits and involvement of other tissues or organs in the generation of variability of L-traits. Also, interactions between differentially expressed genes were found in extracellular matrix (ECM)-receptor interaction, tumor growth factor (TGF)-beta signaling pathway, fatty acid elongation in mitochondria, and adipocytokine signaling pathway, indicating that a substantial fraction of the gene networks could be associated with interactions between differentially expressed genes related to traits under study. A large number of the most overexpressed genes are related to muscle development and functionality and repair mechanisms; they could be good candidates for breeding programs in which the main goal is to enhance meat quality.


Subject(s)
Gene Expression Profiling/methods , Gene Expression Regulation , Meat/standards , Muscle, Skeletal/metabolism , Oligonucleotide Array Sequence Analysis/methods , Swine/genetics , Animals , Gene Regulatory Networks , Muscle, Skeletal/chemistry , RNA, Messenger/metabolism , Random Allocation , Real-Time Polymerase Chain Reaction , Swine/metabolism , Time Factors
11.
Anim Genet ; 43(1): 2-10, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22221019

ABSTRACT

Genetic diversity in and relationships among 26 Creole cattle breeds from 10 American countries were assessed using 19 microsatellites. Heterozygosities, F-statistics estimates, genetic distances, multivariate analyses and assignment tests were performed. The levels of within-breed diversity detected in Creole cattle were considerable and higher than those previously reported for European breeds, but similar to those found in other Latin American breeds. Differences among breeds accounted for 8.4% of the total genetic variability. Most breeds clustered separately when the number of pre-defined populations was 21 (the most probable K value), with the exception of some closely related breeds that shared the same cluster and others that were admixed. Despite the high genetic diversity detected, significant inbreeding was also observed within some breeds, and heterozygote excess was detected in others. These results indicate that Creoles represent important reservoirs of cattle genetic diversity and that appropriate conservation measures should be implemented for these native breeds in order to minimize inbreeding and uncontrolled crossbreeding.


Subject(s)
Cattle/genetics , Genetic Variation , Microsatellite Repeats , Animals , Pedigree
12.
Equine Vet J ; 44(1): 33-42, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21668489

ABSTRACT

REASONS FOR PERFORMING STUDY: Mesenchymal stromal cells (MSCs) represent an attractive source for regenerative medicine. However, prior to their application, fundamental questions regarding molecular characterisation, growth and differentiation of MSCs must be resolved. OBJECTIVES: To compare and better understand the behaviour of equine MSCs obtained from bone marrow (BM) and adipose tissue (AT) in culture. METHODS: Five horses were included in this study. Proliferation rate was measured using MTT assay and cell viability; apoptosis, necrosis and late apoptosis and necrosis were evaluated by flow cytometry. The mRNA expression levels of 7 surface marker genes were quantified using RT-qPCR and CD90 was also analysed by flow cytometry. Differentiation was evaluated using specific staining, measurement of alkaline phosphatase activity and analysis of the mRNA expression. RESULTS: High interindividual differences were observed in proliferation in both cell types, particularly during the final days. Statistically significant differences in viability and early apoptosis of cultured AT- and BM-MSCs were found. The highest values of early apoptosis were observed during the first days of culture, while the highest percentage of necrosis and late apoptosis and lowest viability was observed in the last days. Surface marker expression pattern observed is in accordance to other studies in horse and other species. Osteogenic differentiation was evident after 7 days, with an increasing of ALP activity and mRNA expression of osteogenic markers. Adipogenic differentiation was achieved in BM-MSCs from 2 donors with one of the 16 media tested. Chondrogenic differentiation was also observed. CONCLUSIONS: Proliferation ability is different in AT-MSCs and BM-MSCs. Differences in viability and early apoptosis were observed between both sources and CD34 was only found in AT-MSCs. Differences in their osteogenic and adipogenic potential were detected by staining and quantification of specific tissue markers. POTENTIAL RELEVANCE: To provide data to better understand AT-MSCs and BM-MSCs behaviour in vitro.


Subject(s)
Adipose Tissue/cytology , Bone Marrow Cells/physiology , Horses/physiology , Mesenchymal Stem Cells/physiology , Animals , Apoptosis , Cell Differentiation , Cell Proliferation , Cell Survival , Cells, Cultured , Flow Cytometry , Gene Expression Regulation , Membrane Proteins/genetics , Membrane Proteins/metabolism , Necrosis , Osteogenesis , RNA, Messenger/genetics , RNA, Messenger/metabolism
13.
J Anim Sci ; 89(4): 893-906, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21415418

ABSTRACT

In Iberia there are 51 officially recognized cattle breeds of which 15 are found in Portugal and 38 in Spain. We present here a comprehensive analysis of the genetic diversity and structure of Iberian cattle. Forty of these breeds were genotyped with 19 highly polymorphic microsatellite markers. Asturiana de los Valles displayed the greatest allelic diversity and Mallorquina the least. Unbiased heterozygosity values ranged from 0.596 to 0.787. The network based on Reynolds distances was star-shaped with few pairs of interrelated breeds and a clear cluster of 4 breeds (Alistana/Arouquesa/Marinhoa/Mirandesa). The analysis of the genetic structure of Iberian cattle indicated that the most probable number of population clusters included in the study would be 36. Distance results were supported by the STRUCTURE software indicating a relatively recent origin or possible crossbreeding or both between pairs or small groups of breeds. Five clusters included 2 different breeds (Betizu/Pirenaica, Morucha/Avileña, Parda de Montaña/Bruna de los Pirineos, Barrosã/Cachena, and Toro de Lidia/Brava de Lide), 3 breeds (Berrenda en Negro, Negra Andaluza, and Mertolenga) were divided in 2 independent clusters each, and 2 breeds were considered admixed (Asturiana de los Valles and Berrenda en Colorado). Individual assignation to breeds was not possible in the 2 admixed breeds and the pair Parda de Montaña/Bruna de los Pirineos. The relationship between Iberian cattle reflects their geographical origin rather than their morphotypes. Exceptions to this geographic clustering are most probably a consequence of crossbreeding with foreign breeds. The relative genetic isolation within their geographical origin, the consequent genetic drift, the adaptation to specific environment and production systems, and the influence of African and European cattle have contributed to the current genetic status of Iberian cattle, which are grouped according to their geographical origin. The greater degree of admixture observed in some breeds should be taken into account before using molecular markers for genetic assignment of individuals to breeds.


Subject(s)
Cattle/genetics , Genetic Variation , Animals , Cattle/classification , Cluster Analysis , Evolution, Molecular , Gene Frequency , Microsatellite Repeats , Pedigree , Portugal , Spain , Species Specificity
14.
Animal ; 5(9): 1323-34, 2011 Aug.
Article in English | MEDLINE | ID: mdl-22440277

ABSTRACT

This study is aimed at establishing priorities for the optimal conservation of genetic diversity among a comprehensive group of 40 cattle breeds from the Iberian Peninsula. Different sets of breed contributions to diversity were obtained with several methods that differ in the relative weight attributed to the within- and between-breed components of the genetic variation. The contributions to the Weitzman diversity and the expected heterozygosity (He) account for between- and within-breed variation only, respectively. Contributions to the core set obtained for several kinship matrices, incorporate both sources of variation, as well as the combined contributions of Ollivier and Foulley and those of Caballero and Toro. In general, breeds that ranked high in the different core set applications also ranked high in the contribution to the global He, for example, Sayaguesa, Retinta, Monchina, Berrenda en Colorado or Marismeña. As expected, the Weitzman method prioritised breeds with low contributions to the He, like Mallorquina, Menorquina, Berrenda en Negro, Mostrenca, Vaca Palmera or Mirandesa, all showing highly negative contributions to He - that is, their removal would significantly increase the average He. Weighing the within- and between-breed components with the FST produced a balanced set of contributions in which all the breeds ranking high in both approaches show up. Unlike the other methods, the contributions to the diversity proposed by Caballero and Toro prioritised a good number of Portuguese breeds (Arouquesa, Barrosã, Mertolenga and Preta ranking highest), but this might be caused by a sample size effect. Only Sayaguesa ranked high in all the methods tested. Considerations with regard to the conservation scheme should be made before adopting any of these approaches: in situ v. cryoconservation, selection and adaptation within the breeds v. crossbreeding or the creation of synthetic breeds. There is no general consensus with regard to balancing within- and between-breed diversity and the decision of which source to favour will depend on the particular scenario. In addition to the genetic information, other factors, such as geographical, historical, economic, cultural, etc., also need to be considered in the formulation of a conservation plan. All these aspects will ultimately influence the distribution of resources by the decision-makers.

15.
Neuropathol Appl Neurobiol ; 36(4): 300-11, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20070537

ABSTRACT

AIMS: Copper and manganese levels are altered in mice both lacking PrPc and prion-infected brains. The aim of this study was to analyse the effects of manganese and copper imbalance on neuronal apoptosis in a scrapie-infected Tga20 mouse model. METHODS: Immunoreactivities for the apoptotic proteins Bax and active caspase-3 were evaluated in nine regions of the brain of scrapie-infected and control Tga20 mice treated with one of several diets: depleted cooper (-Cu), loaded manganese (+Mn), depleted copper/loaded manganese (-Cu+Mn) and regular diet. Immunohistochemical determination of NeuN was used to detect possible neuronal loss. RESULTS: Intracellular Bax detection was significantly decreased in animals fed with modified diets, particularly in those treated with copper-depleted diets. A decrease in active caspase-3 was primarily observed in animals fed with enhanced manganese diets. Our results show that the -Cu, -Cu+Mn and +Mn diets protected against apoptosis in scrapie-infected mice. However, NeuN immunolabelling quantification revealed that no diet was sufficient to arrest neuronal death. CONCLUSIONS: With regard to apoptosis induction, the response of Tga20 mice to prion infection was similar to that reported for other mice models. Our results demonstrate the neuroprotective effects of -Cu, -Cu+Mn and +Mn diets in a murine model of scrapie. However, neuronal death induced by infection with prions seems to be independent of apoptosis marker signalling. Moreover, copper-modified diets were neuroprotective against the possible toxicity of the prion transgene in Tga20 control and infected mice even though manganese supplementation could not counteract this toxicity.


Subject(s)
Apoptosis/physiology , Brain/metabolism , Copper/metabolism , Manganese/metabolism , Neurons/metabolism , Scrapie/metabolism , Animals , Caspase 3 , Copper/administration & dosage , Copper/deficiency , DNA-Binding Proteins , Diet , Disease Models, Animal , Manganese/administration & dosage , Manganese/deficiency , Mice , Mice, Inbred C57BL , Mice, Transgenic , Nerve Tissue Proteins/metabolism , Nuclear Proteins/metabolism , Pregnancy Proteins/genetics , Pregnancy Proteins/metabolism , Scrapie/diet therapy , bcl-2-Associated X Protein/metabolism
16.
Anim Biotechnol ; 21(1): 1-13, 2010.
Article in English | MEDLINE | ID: mdl-20024782

ABSTRACT

Scrapie is the archetype of prion diseases, fatal neurodegenerative disorders that affect humans and animals. Gene expression analysis of normal and infected sheep may provide clues to clarify the molecular mechanisms involved in the neuropathology of these diseases. Real time quantitative PCR has become a powerful and accurate technique for examination of transcription patterns in different biological conditions. One of the critical steps in the comparison of transcription profiles is the selection of stable genes for normalization of expression data. In this work, we have investigated the effect of scrapie on the stability of eight commonly used housekeeping genes in the central nervous system of sheep. We found that their stability decreased in scrapie-infected tissues, with the effect of the disease most evident in the medulla oblongata, a highly affected area of the brain stem. The risk of choosing inappropriate housekeeping genes for expression analysis was evaluated. Although the stability of each reference gene was suitable, a wide variation in expression of target genes (BAX and BCL2) was observed when only one or two housekeeping genes were used to normalize. However, reliable results were obtained with a normalization factor based on three reference genes, regardless of their position in a stability ranking.


Subject(s)
Genes, Essential/genetics , Genomic Instability/genetics , Scrapie/genetics , Animals , Cerebellum/metabolism , Diencephalon/metabolism , Female , Gene Expression/genetics , Medulla Oblongata/metabolism , Molecular Sequence Data , Prefrontal Cortex/metabolism , RNA , Reverse Transcriptase Polymerase Chain Reaction , Scrapie/metabolism , Sheep/genetics
17.
Anim Genet ; 40(4): 565-8, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19397523

ABSTRACT

Susceptibility/resistance to scrapie in sheep and goats is influenced by host prion protein gene (PRNP) genotype. In this study, we report the analysis of prion protein gene polymorphisms in 137 goats of two Moroccan populations: D'man and Chaouni. We found seven previously described amino acid polymorphisms at codons 37, 127, 137, 142, 154, 222 and 240, as well as three known silent mutations. In addition, we identified three new allelic variants: 101R and 139S in D'man goats and 145D in D'man and Chaouni individuals. The high frequency of the resistant allele 154H could offer genetic protection against the disease to the analysed animals. A total of 12 haplotypes and 28 genotypes were found, the distribution of which shows significant differences between both groups. Moreover, haplotype frequencies were compared with bibliographic data showing that the haplotype distribution of PRNP in Moroccan populations is genetically similar to Southern Italian and Greek goats.


Subject(s)
Goats/genetics , Haplotypes , Prions/genetics , Alleles , Animals , Crosses, Genetic , Gene Frequency , Morocco , Phylogeny , Polymorphism, Genetic
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