PubMed | INIAV, University of Lisbon, Barao e Barao Lda and University of California at Davis
Type: | Journal: Irish veterinary journal | Year: 2016
Pregnancy toxaemia (PT) is a disease that affects pregnant goats during their last month of gestation and is characterized by a high case fatality rate. This study involved 32 does maintained on a commercial dairy goat farm that were diagnosed with PT. A physical examination was performed on and haematology parameters obtained from each doe, at the time of diagnosis. The data from the 24 PT goats that died was compared with the corresponding data from the 8 PT goats that survived.Polypnea, swollen limbs, anorexia with absence of ruminal motility, recumbency, nervous signs and drooping ears were the most frequently observed clinical manifestations. Nineteen out of 21 recumbent goats died. Sixteen out of 17 goats with anorexia and absence of ruminal motility died. Mean beta-hydroxybutyric acid (BHBA) values in the goats that died were not significantly different from those in goats that survived. The blood values for pH and pCOThe clinical signs most indicative of a poor prognosis are anorexia with absence of ruminal motility and recumbency. Among the blood parameters to be considered, hypokalaemia and metabolic acidosis are the most relevant. Goats with PT have a high mortality and their condition can deteriorate very fast. Based on the authorss experience, a good strategy to minimize the economic losses caused by PT is to focus on the offspring survival rate since an early decision (induction of kidding or caesarian surgery) can increase the number of alive kids.
Gama L.T.,University of Lisbon |
Martinez A.M.,University of Cordoba, Spain |
Carolino I.,INIAV |
Landi V.,University of Cordoba, Spain |
And 6 more authors.
Genetics Selection Evolution | Year: 2013
Background: Native pig breeds in the Iberian Peninsula are broadly classified as belonging to either the Celtic or the Mediterranean breed groups, but there are other local populations that do not fit into any of these groups. Most of the native pig breeds in Iberia are in danger of extinction, and the assessment of their genetic diversity and population structure, relationships and possible admixture between breeds, and the appraisal of conservation alternatives are crucial to adopt appropriate management strategies. Methods. A panel of 24 microsatellite markers was used to genotype 844 animals representing the 17 most important native swine breeds and wild populations existing in Portugal and Spain and various statistical tools were applied to analyze the results. Results: Genetic diversity was high in the breeds studied, with an overall mean of 13.6 alleles per locus and an average expected heterozygosity of 0.80. Signs of genetic bottlenecks were observed in breeds with a small census size, and population substructure was present in some of the breeds with larger census sizes. Variability among breeds accounted for about 20% of the total genetic diversity, and was explained mostly by differences among the Celtic, Mediterranean and Basque breed groups, rather than by differences between domestic and wild pigs. Breeds clustered closely according to group, and proximity was detected between wild pigs and the Mediterranean cluster of breeds. Most breeds had their own structure and identity, with very little evidence of admixture, except for the Retinto and Entrepelado varieties of the Mediterranean group, which are very similar. Genetic influence of the identified breed clusters extends beyond the specific geographical areas across borders throughout the Iberian Peninsula, with a very sharp transition from one breed group to another. Analysis of conservation priorities confirms that the ranking of a breed for conservation depends on the emphasis placed on its contribution to the between- and within-breed components of genetic diversity. Conclusions: Native pig breeds in Iberia reveal high levels of genetic diversity, a solid breed structure and a clear organization in well-defined clusters. © 2013 Gama et al.; licensee BioMed Central Ltd.
Goncalves D.M.,University of Lisbon |
Oliveira C.M.,University of Lisbon |
Acta Horticulturae | Year: 2016
Considering the increased consumer interest in fresh blackberries (Rubus spp.), fruit must be available in supermarket shelves all year round. This encourages offseason production in Portugal, mainly from September to December. Growers use long canes in order to harvest fruit during this period. Considering the extension of the vegetative growth cycle in mild winter climates, cane management is difficult due to excessive vegetative vigor. A trial was setup in order to evaluate the possibility of utilizing this excessive vigor for a double cropping system in blackberry. In nonheated greenhouses, nine blackberry cultivars of different types were evaluated for their suitability for double cropping in early spring (soil) and late autumn (substrate). For each cultivar, two floricane suppression treatments (cutting and no cutting) were applied at the beginning of spring 2011. Four rooting treatments, including tip layering, tip layering followed by cold storage for 15 days after detachment from the stock plant, tip layering using 20-cm tipped primocanes, and simple layering, were also tested during summer 2011. Plants grown without floricanes produced longer primocanes and more nodes per primocane but had smaller cane diameters. Long canes were obtained from each cultivar, except 'Logan Thornless'. In December, one cultivar for each blackberry type was cold-stored from January to June 2012 and then cropped in non-heated tunnels, where they produced fruit from late August to late October. Yields ranged from 0.8 to 4.6 kg plant-1 in the spring (all cultivars) and from 0.9 to 2.3 kg plant-1 in autumn ('Chester Thornless' and 'Olallie' only). The results indicated that double cropping may be economically possible in blackberry using certain cultivars.
Peres C.M.,INIAV |
Alves M.,New University of Lisbon |
Hernandez-Mendoza A.,New University of Lisbon |
Hernandez-Mendoza A.,Research Center en Alimentacion y Desarrollo |
And 7 more authors.
LWT - Food Science and Technology | Year: 2014
The purpose of this work was to screen for and characterize the potential probiotic features of strains of lactic acid bacteria isolated from Galega cultivar fermented olives, to eventually develop an improved probiotic food from plant origin. From 156 isolated strains, 10 were acid - and bile salt tolerant, and exhibited survival rates up to 48%, following simulated digestion. All strains exhibited auto- (4-12%) and co-aggregation features (≥30%), as well as hydrophobicity (5-20%) and exopolysaccharide-producing abilities, while no strain possessed haemolytic capacity or ability to hydrolyse mucin. Antibiotic resistance, oleuropein degradation, proteolytic activity and antimicrobial activity were strain-dependent features. Overall, 10 strains - belonging to Lactobacillus plantarum and Lactobacillus paraplantarum, appear to possess a probiotic value. © 2014 Elsevier Ltd.
PubMed | INIAV and University of Lisbon
Type: Journal Article | Journal: Animal genetics | Year: 2016
The objective of this study was to search for polymorphisms in the ovine prion-related protein (testis-specific) gene (PRNT). Sampling included 567 sheep from eight Portuguese breeds. The PRNT gene-coding region was analyzed by single-strand conformation polymorphism and sequencing, allowing the identification of the first ovine PRNT polymorphisms, in codons 6, 38, 43 and 48: c.17C>T (p.Ser6Phe, which disrupts a consensus arginine-X-X-serine/threonine motif); c.112G>C (p.Gly38>Arg); c.129T>C and c.144A>G (synonymous) respectively. Polymorphisms in codons 6, 38 and 48 occur simultaneously in 50.6% of the animals, 38.8% presenting as heterozygous. To study the distribution of the polymorphism in codon 43, a restriction fragment length polymorphism analysis was performed. Polymorphic variant c.129C, identified in 89.8% of the animals with 32.8% presented as heterozygous, was considered the wild genotype in Portuguese sheep. Eight different haplotypes which have comparable distribution in all breeds were identified for the PRNT gene. In conclusion, the PRNT coding region is highly polymorphic in sheep, unlike the prion protein 2 dublet gene (PRND), in which we previously found only one synonymous substitution (c.78G>A), in codon 26. The absence or reduced number of PRND heterozygotes (c.78G>A) was significantly associated with three PRNT haplotypes (17C-112G-129T-144A,17CT-112GC-129CT-144AG and 17T-112C-129C-144G), and the only three animals found homozygous at c.78A had the 17C-112G-129C-144A PRNT haplotype. These results constitute evidence of an association between polymorphic variation in PRND and PRNT genes, as has already been observed for PRND and prion protein gene (PRNP).
PubMed | INIAV, University of Lisbon, New University of Lisbon and University Nova Of Lisboaoeiras
Type: | Journal: Frontiers in plant science | Year: 2016
The establishment of stress resilient sugar beets (Beta vulgaris spp. vulgaris) is an important breeding goal since this cash crop is susceptible to drought and salinity. The genetic diversity in cultivated sugar beets is low and the beet wild relatives are useful genetic resources for tolerance traits. Three wild beet populations (Beta vulgaris spp. maritima) from contrasting environments, Vaiamonte (VMT, dry inland hill), Comporta (CMP, marsh) and Oeiras (OEI, coastland), and one commercial sugar beet (Isella variety, SB), are compared. At the genetic level, the use of six microsatellite allowed to detect a total of seventy six alleles. It was observed that CMP population has the highest value concerning the effective number of alleles and of expected heterozygosity. By contrast, sugar beet has the lowest values for all the parameters considered. Loci analysis with STRUCTURE allows defining three genetic clusters, the sea beet (OEI and CMP), the inland ruderal beet (VMT) and the sugar beet (SB). A screening test for progressive drought and salinity effects demonstrated that: all populations were able to recover from severe stress; drought impact was higher than that from salinity; the impact on biomass (total, shoot, root) was population specific. The distinct strategies were also visible at physiological level. We evaluated the physiological responses of the populations under drought and salt stress, namely at initial stress stages, late stress stages, and early stress recovery. Multivariate analysis showed that the physiological performance can be used to discriminate between genotypes, with a strong contribution of leaf temperature and leaf osmotic adjustment. However, the separation achieved and the groups formed are dependent on the stress type, stress intensity and duration. Each of the wild beet populations evaluated is very rich in genetic terms (allelic richness) and exhibited physiological plasticity, i.e., the capacity to physiologically adjust to changing environments. These characteristics emphasize the importance of the wild beet ecotypes for beet improvement programs. Two striking ecotypes are VMT, which is the best to cope with drought and salinity, and CMP which has the highest root to shoot ratio. These genotypes can supply breeding programs with distinct goals.
PubMed | INIAV and University of Lisbon
Type: | Journal: Reproductive biology and endocrinology : RB&E | Year: 2015
In cryopreservation, oocytes are subjected to extreme hyperosmotic conditions, inducing large volume changes that, along with an abrupt temperature drop, interfere with their developmental competence. Our objectives in this work were to find conditions enabling an increase in oocyte cryosurvival and subsequent development.Abattoir-derived bovine oocytes were cultured without (Control group) or with trans-10,cis-12 conjugated linoleic acid isomer (CLA group). Comparative observations were made for 1) the oocyte developmental competence after exposure to cryoprotectants followed or not by vitrification/warming, 2) the oocyte membrane permeability to water (using the non-permeant cryoprotectant sucrose) and 3) the oocyte membrane permeability to two cryoprotectants (ethylene glycol, EG, and dimethyl sulfoxide, DMSO). Mature oocytes cultured with or without CLA and vitrified/warmed or only exposed to cryoprotectants without vitrification were subjected to in vitro fertilization; embryo culture proceeded until the blastocyst stage. The oocyte membrane permeabilities to water and cryoprotectants were estimated using mature oocytes subjected to hyperosmotic challenges. For water permeability, 200mM sucrose was used, whereas for the cryoprotectant permeability, a 10% solution of both EG and DMSO was used. The data were analyzed using the MIXED procedure and StudentsT-test.CLA supplementation improves the developmental competence of vitrified/warmed and cryoprotectants exposed oocytes (p<0.01) and reduces their membrane permeability to water (37%, p<0.001) and to cryoprotectants (42%, p<0.001).By slowing the fluxes of water and of permeant cryoprotectants, CLA contributed to improved oocyte cryosurvival and post-thawed viability. This isomer supplementation to the maturation media should be considered when designing new protocols for oocyte cryopreservation.
Fonseca F.,University of Algarve |
Duarte V.,University of Algarve |
Teixeira Santos M.,INIAV |
Brazao J.,INIAV |
Archives of Virology | Year: 2016
This work describes the first molecular characterization of grapevine virus B (GVB) in Portuguese grapevine cultivars. During a routine screening of 44 accessions in the National Collection of Grapevine Varieties (CAN PRT051), 17 were found infected with GVB in DAS-ELISA assays with commercial antibodies. However, only six of the corresponding isolates were successfully amplified using primer pairs described in the literature. The sequence variants (ORF4-3’UTR, 1147 nt) retrieved from these isolates segregated into two phylogenetic groups, which included sequences from complete genomes available in GenBank. The highly discrepant results obtained using serological and RT-PCR-based diagnostic tools led to the design of a primer pair for detection of GVB, which allowed the amplification of a 606-bp GVB-specific fragment from all DAS-ELISA-positive isolates and also revealed the existence of false negatives in the serological testing. © 2016 Springer-Verlag Wien
PubMed | INIAV and University of Algarve
Type: Journal Article | Journal: Archives of virology | Year: 2016
This work describes the first molecular characterization of grapevine virus B (GVB) in Portuguese grapevine cultivars. During a routine screening of 44 accessions in the National Collection of Grapevine Varieties (CAN PRT051), 17 were found infected with GVB in DAS-ELISA assays with commercial antibodies. However, only six of the corresponding isolates were successfully amplified using primer pairs described in the literature. The sequence variants (ORF4-3UTR, 1147nt) retrieved from these isolates segregated into two phylogenetic groups, which included sequences from complete genomes available in GenBank. The highly discrepant results obtained using serological and RT-PCR-based diagnostic tools led to the design of a primer pair for detection of GVB, which allowed the amplification of a 606-bp GVB-specific fragment from all DAS-ELISA-positive isolates and also revealed the existence of false negatives in the serological testing.
Pereira J.,Polytechnic Institute of Viseu |
Pereira J.,University of Trás os Montes e Alto Douro |
Figueiredo N.,INIAV |
Goufo P.,University of Trás os Montes e Alto Douro |
And 6 more authors.
Atmospheric Environment | Year: 2013
Methane (CH4) and nitrous oxide (N2O) emissions from flooded rice fields have been rarely measured in Europe. A field study was carried out in an intermittent flooded rice field at central Portugal to investigate if global warming under Mediterranean conditions, elevated soil temperature (+2°C) and atmospheric [CO2] (550ppm), could lead to significant effects in CH4 and N2O emissions. The experimental design consisted of three treatments arranged in a randomized complete block design with three replicates. To assess the effects of ambient temperature and actual atmospheric [CO2] (375ppm), plots were laid under open-field rice conditions. Using open-top chambers, two other treatments were established: one to assess the effect of elevated temperature and actual atmospheric [CO2] and a third treatment to evaluate the combined effect of elevated temperature and atmospheric [CO2]. Measurements of CH4 and N2O fluxes were made throughout two consecutive growing seasons in the field using the closed chamber technique. Elevation of temperature with or without elevated atmospheric [CO2] increased CH4 emissions by 50%, but this increase was not significant compared to the open-field condition. As for N2O, elevated temperature alone or combined with elevated atmospheric [CO2] had no significant effect on emissions relative to the open-field treatment. The estimated seasonal CH4 EF for the Portuguese flooded rice fields was 10.0gCH4m-2, while the EF for N2O emissions was 1.4% of N input. These results suggested that default seasonal CH4 and N2O EFs currently used by the Portuguese inventory were not appropriated. © 2013 Elsevier Ltd.