Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Theriogenology ; 208: 43-51, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37295289

RESUMEN

The objectives of this study were to establish baseline information for seminal traits in Lusitano stallions, to assess the impact of inbreeding, interval between collections and age on semen quality during the breeding and non-breeding seasons, and to estimate the corresponding genetic parameters. A total of 2129 ejaculates by 146 Lusitano stallions used for artificial insemination, obtained from four equine reproduction centers distributed throughout Portugal, over a period of 14 years (2008-2021), were included in the study. The seminal traits analyzed, and the corresponding means and standard deviations, were gel-free volume (56.95 ± 28.76 mL), concentration (186.48 ± 104.68 × 106), motility (64.1 ± 16.9%), total number of spermatozoa (TNS) (9.271 ± 4.956 × 109) and total number of motile spermatozoa per ejaculate (TNMS) (5.897 ± 3.587 × 109). These results are in the normal range of values described for other breeds. In the stallions analyzed, the mean value for the inbreeding coefficient was 7.93 ± 5.29%, and for age it was 12.70 ± 6.83 years. A significant decline in sperm concentration, motility, TNS, and TNMS was observed as inbreeding increased. The season also influenced sperm concentration, motility, TNS and TNMS, with the highest values observed during the breeding season. When considering the impact of age on Lusitano seminal parameters, results showed a nonlinear relationship, with a positive effect until 18 years of age for volume, motility, TNS and TNMS and a negative effect after this age, with a slow decrease. However, age had a markedly negative effect on sperm concentration. The interval between semen collections only affected (P < 0.05) sperm motility, with a regression coefficient of +1.89 ± 2.17% per additional day. Genetic parameters were estimated with an Animal Model, and the estimated heritability (repeatability) was 0.27 (0.35) for volume, 0.02 (0.38) for sperm concentration, 0.24 (0.44) for motility, 0.29 (0.39) for TNS and 0.41 (0.41) for TNMS. These results suggest that it is possible to improve semen quality by selection and that the properties of semen produced by a stallion tend to remain consistent throughout its lifetime. Furthermore, the impact of inbreeding should be taken into consideration when selecting Lusitano stallions for fertility.


Asunto(s)
Endogamia , Análisis de Semen , Masculino , Animales , Caballos/genética , Análisis de Semen/veterinaria , Semen , Motilidad Espermática/genética , Recuento de Espermatozoides/veterinaria
2.
Euro Surveill ; 27(44)2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36330821

RESUMEN

BackgroundThe emergence of colistin resistance is a One Health antimicrobial resistance challenge worldwide. The close contact between companion animals and humans creates opportunities for transmission and dissemination of colistin-resistant bacteria.AimTo detect potential animal reservoirs of colistin-resistant Escherichia coli and investigate the possible sharing of these bacteria between dogs, cats and their cohabiting humans in the community in Lisbon, Portugal.MethodsA prospective longitudinal study was performed from 2018 to 2020. Faecal samples from dogs and cats either healthy or diagnosed with a skin and soft tissue or urinary tract infection, and their cohabiting humans were screened for the presence of colistin-resistant E. coli. All isolates were tested by broth microdilution against colistin and 12 other antimicrobials. Colistin-resistant isolates were screened for 30 resistance genes, including plasmid-mediated colistin resistance genes (mcr-1 to mcr-9), and typed by multilocus sequence typing. Genetic relatedness between animal and human isolates was analysed by whole genome sequencing.ResultsColistin-resistant E. coli strains harbouring the mcr-1 gene were recovered from faecal samples of companion animals (8/102; 7.8%) and humans (4/125; 3.2%). No difference between control and infection group was detected. Indistinguishable multidrug-resistant E. coli ST744 strains harbouring the mcr-1 gene were found in humans and their dogs in two households.ConclusionsThe identification of identical E. coli strains containing the plasmid-mediated mcr-1 gene in companion animals and humans in daily close contact is of concern. These results demonstrate the importance of the animal-human unit as possible disseminators of clinically important resistance genes in the community setting.


Asunto(s)
Infecciones por Escherichia coli , Proteínas de Escherichia coli , Animales , Gatos/microbiología , Perros/microbiología , Humanos , Antibacterianos/farmacología , Colistina/farmacología , Farmacorresistencia Bacteriana/genética , Escherichia coli , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/veterinaria , Infecciones por Escherichia coli/microbiología , Proteínas de Escherichia coli/genética , Estudios Longitudinales , Pruebas de Sensibilidad Microbiana , Plásmidos/genética , Portugal/epidemiología , Estudios Prospectivos
3.
Animals (Basel) ; 11(1)2021 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-33467081

RESUMEN

Neutrophils can originate neutrophil extracellular traps (NETs). Myeloperoxidase (MPO) is a peroxidase found in NETs associated to equine endometrosis and can be inhibited by 4-aminobenzoic acid hydrazide (ABAH). Metallopeptidases (MMPs) participate in extracellular matrix stability and fibrosis development. The objectives of this in vitro work were to investigate, in explants of mare's endometrium, (i) the ABAH capacity to inhibit MPO-induced collagen type I (COL1) expression; and (ii) the action of MPO and ABAH on the expression and gelatinolytic activity of MMP-2/-9. Explants retrieved from the endometrium of mares in follicular or mid-luteal phases were treated with MPO, ABAH, or their combination, for 24 or 48 h. The qPCR analysis measured the transcription of COL1A2, MMP2, and MMP9. Western blot and zymography were performed to evaluate COL1 protein relative abundance and gelatinolytic activity of MMP-2/-9, respectively. Myeloperoxidase elevated COL1 relative protein abundance at both treatment times in follicular phase (p < 0.05). The capacity of ABAH to inhibit MPO-induced COL1 was detected in follicular phase at 48 h (p < 0.05). The gelatinolytic activity of activated MMP-2 augmented in mid-luteal phase at 24 h after MPO treatment, but it was reduced with MPO+ABAH treatment. The activity of MMP-9 active form augmented in MPO-treated explants. However, this effect was inhibited by ABAH in the follicular phase at 48 h (p < 0.05). By inhibiting the pro-fibrotic effects of MPO, it might be possible to reduce the development of endometrosis. Metallopeptidase-2 might be involved in an acute response to MPO in the mid-luteal phase, while MMP-9 might be implicated in a prolonged exposition to MPO in the follicular phase.

4.
Front Vet Sci ; 7: 582211, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33195599

RESUMEN

Although proteases found in neutrophil extracellular traps (NETs) have antimicrobial properties, they also stimulate collagen type 1 (COL1) production by the mare endometrium, contributing for the development of endometrosis. Cathepsin G (CAT), a protease present in NETs, is inhibited by specific inhibitors, such as cathepsin G inhibitor I (INH; ß-keto-phosphonic acid). Matrix metallopeptidases (MMPs) are proteases involved in the equilibrium of the extracellular matrix. The objective of this study was to investigate the effect of CAT and INH (a selective CAT inhibitor) on the expression of MMP-2 and MMP-9 and on gelatinolytic activity. In addition, the putative inhibitory effect of INH on CAT-induced COL1 production in mare endometrium was assessed. Endometrial explants retrieved from mares in follicular phase or midluteal phase were treated for 24 or 48 h with CAT, inhibitor alone, or both treatments. In explants, transcripts (quantitative polymerase chain reaction) of COL1A2, MMP2, and MMP9, as well as the relative abundance of COL1 protein (Western blot), and activity of MMP-2 and MMP-9 (zymography) were evaluated. The protease CAT induced COL1 expression in explants, at both estrous cycle phases and treatment times. The inhibitory effect of INH was observed on COL1A2 transcripts in follicular phase at 24-h treatment, and in midluteal phase at 48 h (P < 0.05), and on the relative abundance of COL protein in follicular phase and midluteal phase explants, at 48 h (P < 0.001). Our study suggests that MMP-2 might also be involved in an earlier response to CAT, and MMP-9 in a later response, mainly in the follicular phase. While the use of INH reduced CAT-induced COL1 endometrial expression, MMPs might be involved in the fibrogenic response to CAT. Therefore, in mare endometrium, the use of INH may be a future potential therapeutic means to reduce CAT-induced COL1 formation and to hamper endometrosis establishment.

5.
Animals (Basel) ; 10(11)2020 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-33203139

RESUMEN

A total of 137,927 controls of 22,932 Murciano-Granadina first lactation goats (measured between 1996-2016) were evaluated to determine the influence of the number of kids, season, year and farm on total milk yield, daily milk yield, lactation length, total production of fat and protein and percentages of fat and protein. All factors analyzed had a significant effect on the variables studied, except for the influence of the number of kids on the percentages of fat and protein, where the variation was very small. Goats with two offspring produced nearly 15% more milk, fat and protein per lactation compared to goats with simple kids. Kiddings occurring in summer-autumn resulted in average milk, fat and protein yields nearly 14, 19 and 23% higher when compared to winter-spring kiddings. Lactation curves were evaluated to determine the effects of the number of kids and season, using the linearized version of the model of Wood in random regression analyses. Peak Yield increased by about 0.3 kg per additional offspring at kidding, but persistence was higher in goats with single offspring. The kidding season significantly influenced the lactation curve shape. Hence summer-kidding goats were more productive, and peak occurred earlier, while a higher persistence was observed in goats kidding during autumn.

6.
Animals (Basel) ; 10(5)2020 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-32429399

RESUMEN

Neutrophil extracellular traps (NETs) fight endometritis, and elastase (ELA), a protease found in NETs, might induce collagen type I (COL1) accumulation in equine endometrium. Metallopeptidases (MMPs) are involved in extracellular matrix balance. The aim was to evaluate the effects of ELA and sivelestat (selective elastase inhibitor) on MMP-2 and MMP-9 expression and gelatinolytic activity, as well as the potential inhibitory effect of sivelestat on ELA-induced COL1 in equine endometrium. Endometrial explants from follicular (FP) and mid-luteal (MLP) phases were treated for 24 or 48 h with ELA, sivelestat, and their combination. Transcripts of COL1A2, MMP2, and MMP9 were evaluated by qPCR; COL1 protein relative abundance by Western blot, and MMP-2 and MMP-9 gelatinolytic activity by zymography. In response to ELA treatment, there was an increase in MMP2 mRNA transcription (24 h) in active MMP-2 (48 h), both in FP, and in MMP9 transcripts in FP (48 h) and MLP (24 h) (p < 0.05). Sivelestat inhibited ELA-induced COL1A2 transcripts in FP (24 h) and MLP (24 h, 48 h) (p < 0.05). The sivelestat inhibitory effect was detected in MMP9 transcripts in FP at 48 h (p < 0.05), but proteases activity was unchanged. Thus, MMP-2 and MMP-9 might be implicated in endometrium fibrotic response to ELA. In mare endometrium, sivelestat may decrease ELA-induced COL1 deposition and hinder endometrosis development.

7.
Br Poult Sci ; 59(2): 218-226, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29424549

RESUMEN

1. Endo-1,4-ß-xylanase is known to improve the nutritive value of wheat-based diets for poultry by degrading dietary arabinoxylans. However, broilers' response to supplementation of wheat-based diets with exogenous endo-1,4-ß-xylanase is not always observed. 2. In this study, 108 different wheat lots were analysed for levels of extract viscosity as well as for endogenous endo-1,4-ß-xylanase activity, and the impact of these two variables in animal performance was tested. 3. Results revealed that endogenous endo-1,4-ß-xylanase activity and extract viscosity content varied widely among different wheat lots. Thus, a trial was conducted to evaluate the efficacy of exogenous enzyme supplementation in broiler diets using wheats with different levels of extract viscosity and endogenous endo-1,4-ß-xylanase activity. 4. The data revealed that exogenous enzyme supplementation was only effective when the wheat present in the diet had high levels of extract viscosity (14.8 cP) with low endogenous endo-1,4-ß-xylanase activity (347.0 U/kg). Nevertheless, it is apparent that exogenous microbial xylanases reduce digesta extract viscosity and feed conversion ratio independently of the endogenous properties presented by different wheat lots. 5. The data suggest that extract viscosity and/or endogenous endo-1,4-ß-xylanase activity affect the response to enzyme supplementation by poultry fed on wheat-based diets.


Asunto(s)
Pollos/fisiología , Endo-1,4-beta Xilanasas/metabolismo , Valor Nutritivo , Polisacáridos/metabolismo , Triticum/química , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Suplementos Dietéticos/análisis , Relación Dosis-Respuesta a Droga , Endo-1,4-beta Xilanasas/administración & dosificación , Extractos Vegetales/química , Distribución Aleatoria , Viscosidad
8.
Front Genet ; 6: 314, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26539210

RESUMEN

Livestock conservation practice is changing rapidly in light of policy developments, climate change and diversifying market demands. The last decade has seen a step change in technology and analytical approaches available to define, manage and conserve Farm Animal Genomic Resources (FAnGR). However, these rapid changes pose challenges for FAnGR conservation in terms of technological continuity, analytical capacity and integrative methodologies needed to fully exploit new, multidimensional data. The final conference of the ESF Genomic Resources program aimed to address these interdisciplinary problems in an attempt to contribute to the agenda for research and policy development directions during the coming decade. By 2020, according to the Convention on Biodiversity's Aichi Target 13, signatories should ensure that "…the genetic diversity of …farmed and domesticated animals and of wild relatives …is maintained, and strategies have been developed and implemented for minimizing genetic erosion and safeguarding their genetic diversity." However, the real extent of genetic erosion is very difficult to measure using current data. Therefore, this challenging target demands better coverage, understanding and utilization of genomic and environmental data, the development of optimized ways to integrate these data with social and other sciences and policy analysis to enable more flexible, evidence-based models to underpin FAnGR conservation. At the conference, we attempted to identify the most important problems for effective livestock genomic resource conservation during the next decade. Twenty priority questions were identified that could be broadly categorized into challenges related to methodology, analytical approaches, data management and conservation. It should be acknowledged here that while the focus of our meeting was predominantly around genetics, genomics and animal science, many of the practical challenges facing conservation of genomic resources are societal in origin and are predicated on the value (e.g., socio-economic and cultural) of these resources to farmers, rural communities and society as a whole. The overall conclusion is that despite the fact that the livestock sector has been relatively well-organized in the application of genetic methodologies to date, there is still a large gap between the current state-of-the-art in the use of tools to characterize genomic resources and its application to many non-commercial and local breeds, hampering the consistent utilization of genetic and genomic data as indicators of genetic erosion and diversity. The livestock genomic sector therefore needs to make a concerted effort in the coming decade to enable to the democratization of the powerful tools that are now at its disposal, and to ensure that they are applied in the context of breed conservation as well as development.

9.
J Hered ; 101(2): 201-10, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-19965912

RESUMEN

Genetic structure and diversity of 13 Portuguese native and 3 imported cattle breeds were assessed with 39 microsatellites. Allelic richness per locus was high, with an overall average of 8.3 +/- 2.5. The mean observed and expected heterozygosities were 0.673 +/- 0.043 and 0.691 +/- 0.034, respectively. The mean number of alleles per breed ranged between 5.36 +/- 1.27 and 7.87 +/- 2.66. Brava de Lide and Mirandesa breeds had the lowest genetic diversity, whereas Minhota, Arouquesa, and Mertolenga had the highest. Significant (P < 0.05) heterozygote deficit was detected in all breeds except Garvonesa, Marinhoa, Minhota, and Limousin. Hardy-Weinberg deviations are most probably due to inbreeding, particularly in Alentejana, Brava de Lide, Mertolenga, and Ramo Grande (F(is) > 0, P < 0.0001). Based on the principal component and the Neighbor-Net analyses, Mirandesa was the most genetically distinct breed. Even though admixture was detected across all breeds (6.7%, q < 0.800), the molecular structure was consistent with original breed designations, with the exception of Cachena that had a clear influence of Barrosã (K = 15). Mertolenga showed substructure with independent clustering of red speckled animals. The percentage animals correctly assigned was >or=90 in all breeds except Cachena, Garvonesa, and Preta (q >or= 0.800). The results obtained here confirmed that high levels of genetic diversity exist within Portuguese native cattle and that the breeds are highly structured. Conservation measures should be implemented for all native breeds to minimize inbreeding.


Asunto(s)
Bovinos/genética , Variación Genética , Secuencias Repetidas en Tándem/genética , Animales , Cruzamiento , Frecuencia de los Genes , Marcadores Genéticos/genética , Variación Genética/fisiología , Genética de Población , Endogamia , Portugal , Análisis de Secuencia de ADN/métodos
10.
J Hered ; 100(2): 148-57, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-18832111

RESUMEN

DNA samples from 307 males of 13 Portuguese native cattle breeds, 57 males of the 3 major exotic breeds in Portugal (Charolais, Friesian, and Limousin), and 5 Brahman (Bos indicus) were tested for 5 single nucleotide polymorphisms, 1 "indel," and 7 microsatellites specific to the Y chromosome. The 13 Y-haplotypes defined included 3 previously described patrilines (Y1, Y2, and Y3) and 10 new haplotypes within Bos taurus. Native cattle contained most of the diversity with 7 haplotypes (H2Y1, H3Y1, H5Y1, H7Y2, H8Y2, H10Y2, and H12Y2) found only in these breeds. H6Y2 and H11Y2 occurred in high frequency across breeds including the exotics. Introgression of Friesian cattle into Ramo Grande was inferred through their sharing of haplotype H4Y1. Among the native breeds, Mertolenga had the highest haplotype diversity (0.68 +/- 0.07), Brava de Lide was the least differentiated. The analyses of molecular variance showed significant (P < 0.0001) differences between breeds with more than 64% of the total genetic variation found among breeds within groups and 33-35% within breeds. The detection of INRA189-104 allele in 8 native breeds suggested influence of African cattle in breeds of the Iberian Peninsula. The presence in Portuguese breeds of Y1 patrilines, also found in aurochs, could represent more ancient local haplotypes.


Asunto(s)
Bovinos/genética , Haplotipos , Polimorfismo de Nucleótido Simple , Secuencias Repetidas en Tándem , Cromosoma Y/genética , Animales , Cruzamiento , Mapeo Cromosómico , Especiación Genética , Masculino , Filogenia , Portugal
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...