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This study aimed to characterize the hot iron branding (HIB) procedure by assessing its implications for animal welfare and its efficiency for cattle identification. The study was carried out in two stages: First, with 37 Nellore calves, by measuring the skin temperatures in the place of HIB application (ONB) and 10 cm above it (OFFB) immediately after its application and during four consecutive days, the time required for application of each HIB digit and the occurrences of rebranding; second, with two batches of cows (N = 97 and N = 94, respectively, by measuring the time spent to read cattle ID and comparing the efficiency of HIB vs. EET (electronic ear tag) and visual ear tags (VET) vs. EET. Skin temperature was significantly affected by the interaction between the place where the skin temperatures were taken (on and 10 cm above the HIB) and assessment day, with temperatures in ONB on days d0 and d2 being higher than in OFFB (p < 0.05), and 86% of the calves required at least one rebranding. EET reading was faster than HIB and VET (p < 0.001), and fewer errors were made when reading EET than HIB (1/97 vs. 17/97) and VET (2/94 vs. 12/94). We concluded that HIB potentially compromises cattle welfare and has a lower efficiency for cattle identification than EET and VET.

This study aimed to identify behavioral and morphological traits of Nellore cattle that can influence calves’ survival and pre-weaning performance. It was performed in two units of a large-scale cow–calf operation farm located in the Central-West region of Brazil, with 975 cow–calf dyads, by scoring cows’ maternal protective behavior, body condition, horns, udder suspension (US), teat size (TS) and calves’ vigor. TS was used to determine teat symmetry (TSm). The production unit where calves were born, their birth date, sex, and birth (BW) and weaning weights were also recorded. Cow ages at calving and production units were used to categorize the cows into twelve classes (Cage). The Shapiro–Wilk test alongside tables of frequencies were used to determine if continuous and categorical variables followed a normal distribution, respectively. Two datasets were considered in statistical analyses: (i) 975 dyad records were used to identify potential factors influencing calf survivability and (ii) 936 records of weaned calves were used to assess pre-weaning performance. Generalized linear models were used to assess the effect of target traits on the calves’ weight adjusted for 210 days of age (W210, kg) and pre-weaning average daily gain (preADG, kg/day). Tukey’s test was used to compare W210 and preADG means. Pearson’s correlation coefficients were estimated between BW, W210 and preADG. Cage, US and the TSm significantly affected pre-weaning calf performance (p < 0.01). Older cows (independently of the production unit) and those with intermediate US and symmetrical teats weaned heavier calves. As expected, positive and significant correlation was observed between BW and preADG (r = 0.35), which, in turn, was highly correlated with W210 (r = 0.99). We concluded that none of the behavioral and morphological traits influenced calf survivability, but cow age, US and TSm impacted pre-weaning performance, with 8- to 11-year-old cows and those with intermediate US and symmetric teats leading to better calf performance at weaning.

The implantation of left ventricular assist devices (LVADs) has been increasing, with good long-term results, in parallel with a growing population with advanced heart failure (HF). However, in some European countries, LVADs are still underused, with one of the main issues being the patient's late referral. On the contrary, the use of transcatheter edge-to-edge mitral valve repair (TEER) has exponentially increased over the past decade, expanding its potential use even in patients on the heart transplantation waiting list. Even though the study populations of the main trials that investigated the prognostic impact of LVAD and TEER are different, in clinical practice a clear distinction might not be so clear. Therefore, patients with refractory HF symptoms and significant mitral regurgitation should be thoroughly evaluated through a multidisciplinary Heart Team meeting with both an advanced HF specialist and interventional cardiologist, to avoid futile procedures and to define the optimal timing for advanced HF therapies, when they are indicated. We analyzed the main available studies and registries on both TEERs and LVADs and we compared their populations and outcomes, to provide the current evidence on the use of LVAD and TEER in the HF population, especially in the light of the recently released 5-year follow-up results, giving some insights on the Italian situation, and finally to stress the importance of a solid HF network between hospitals, aiming for advanced HF patients’ timely referral for LVAD or heart transplants.

Stuttering is a multidimensional neurodevelopmental disorder that comprises primary and secondary behaviors but also feelings and attitudes. These ones have a huge importance in the overall characterization and impact of stuttering. This research aims to: 1) guarantee the adaptation and content validation of the assessment instrument A-19 to European Portuguese, and 2) analyze A-19 construct validity through a pilot study. Across-sectional , quantitative and qualitative study was developed to ensure the adaptation and content validation of A-19. The achievement of semantic, conceptual, experiential and idiomatic equivalences was only possible after the experts’ debate of several items concerning meaning, concept and cultural experience.The final Portuguese version of A-19 was used in a pilot study in which 42 children participated (21 children who stutter and 21 children who do not stutter). The group of school-age children who stutter presented a higher A-19 mean (6.29) in comparison with children who do not stutter (5.48), although the difference was not statistically significant. The Portuguese Version of A19 identifies the differences in feelings and attitudes between school age children who do and who do not stutter. The fact that this sample of children who stutter is already attending speech and language therapy sessions in which emotional, behavioural and cognitive reactions are explored, may have contributed to a non-significative difference in A-19 scores. The content and construct validity of A-19 European Portuguese Version is assured, as so this is a valid instrument to assess feelings and attitudes of school age children who stutter.

With the increase in cultivated areas, one of the great challenges faced by eucalyptus growers is abiotic stresses, especially because new areas are often affected by water deficit. Therefore, the identification of tolerant genotypes is important to overcome this problem. Thus, the objective of this work was to characterize the germinative and physiological performance of eucalyptus species under abiotic stress. Four Eucalyptus species (E. brassiana, E. camaldulensis, E. saligna, and E. urophylla) were evaluated in two experiments. In the first experiment, the germination potential was assessed under two temperatures (25 and 35 °C) and 11 water potentials of the substrate: 0 (deionized water), -0.05, -0.10, -0.15, -0.20, -0.25, -0.30, -0.40, -0.60, -0.80, and -1.0 MPa. In the second experiment, the species were evaluated in a protected environment under two water regimes comprised by 60% and 20% of the maximum water retention capacity by the soil of the pots. Regarding germination, E. saligna was the most sensitive species to stress, showing only 48% germination on 0 MPa potential (35 °C) and under substrate water deficit it reduced 50% germination on -0.21 MPa (25 °C) and -0.16 MPa potential (35 °C). On the other hand, E. brassiana maintained germination at both temperatures and reduced half of its germination at potentials of -0.33 MPa (25 °C) and -0.32 MPa (35 °C). In protected environment, the physiological metabolism of plants decreased under lower water availability. E. saligna was the species with the highest reduction for the rate of net assimilation and efficiency in water use. In addition, E. camaldulensis showed better physiological performance under water deficit. Thus, E. brassiana and E. camaldulensis would be the most suitable species to be used for breeding program aiming to improve water deficit tolerance. E. saligna is indicated for places with a mild climate and with good water availability. The behavior of the species between the experiments showed that under certain conditions there are correspondences in performance, which indicates that this type of experiment assists in the characterization of species, especially when considering the establishment and initial plant development.

Abstract Background Colossoma macropomum (tambaqui) and Piaractus mesopotamicus (pacu) are good fish species for aquaculture. The tambacu, individuals originating from the induced hybridization of the female tambaqui with the male pacu, present rapid growth and robustness, characteristics which have made the tambacu a good choice for Brazilian fish farms. Here, we used small RNA sequencing to examine global miRNA expression in the genotypes pacu (PC), tambaqui (TQ), and hybrid tambacu (TC), (Juveniles, n = 5 per genotype), to better understand the relationship between tambacu and its parental species, and also to clarify the mechanisms involved in tambacu muscle growth and maintenance based on miRNAs expression. Results Regarding differentially expressed (DE) miRNAs between the three genotypes, we observed 8 upregulated and 7 downregulated miRNAs considering TC vs. PC; 14 miRNAs were upregulated and 10 were downregulated considering TC vs. TQ, and 15 miRNAs upregulated and 9 were downregulated considering PC vs. TQ. The majority of the miRNAs showed specific regulation for each genotype pair, and no miRNA were shared between the 3 genotype pairs, in both up- and down-regulated miRNAs. Considering only the miRNAs with validated target genes, we observed the miRNAs miR-144-3p, miR-138-5p, miR-206-3p, and miR-499-5p. GO enrichment analysis showed that the main target genes for these miRNAs were grouped in pathways related to oxygen homeostasis, blood vessel modulation, and oxidative metabolism. Conclusions Our global miRNA analysis provided interesting DE miRNAs in the skeletal muscle of pacu, tambaqui, and the hybrid tambacu. In addition, in the hybrid tambacu, we identified some miRNAs controlling important molecular muscle markers that could be relevant for the farming maximization.

Abstract The in vitro sporulation of Didymella bryoniae is of great importance for studies that require pure inoculum and in large quantities. Thus, the objectives of this study were to identify the best condition for D. bryoniae sporulation combining different light spectra (UV-A or UV-B light, white light, and continuous dark), with distinct culture media (PDA, V8, ML, and PDAB) and, to evaluate fungus’ survivability stored at -20°C over time. The fungus samples were only able to sporulate when subjected to the UV-B light treatment, regardless of the culture medium. The highest appearance of spores conidium type was observed in the PDAB medium, and the lowest production occurred in the ML medium. Reproductive structures, such as perithecia and pycnidia, were observed in all culture media. However, there was considerable variation in the amount of each structure between the different culture media. The ML and V8 media showed a greater number of perithecia and the PDA and PDAB media presented a greater proportion of pycnidia compared to perithecia. The storage duration at -20°C did not affect mycelial growth or mycelial growth rate. In conclusion, the UV-B light is essential for D. bryoniae in vitro sporulation. Moreover, the culture medium composition influences the type of fungal structure produced, as well as spores’ size and quantity. Freezing at -20°C is an efficient technique that can be used to store D. bryoniae for at least five months without loss of viability.

Purpose: Children with Autism Spectrum Disorder (ASD) and Developmental Language Disorder (DLD) frequently face pragmatic impairments which may result in learning, socialization, and mental health difficulties, therefore early intervention is crucial. In Portugal, the Pragmatic Intervention Programme (PICP) has been recently developed and validated, but its effects are unknown. This study aims to determine the effects of the PICP on preschool-age children with ASD or DLD with pragmatic impairments. Methods: A non-randomized controlled trial has been conducted. The children (n = 20) were assigned to the intervention (n = 11) or the control group (waiting list) (n = 9). Each child attended 24 PICP-based intervention sessions provided by a Speech and Language Therapist in kindergarten. The primary outcome measure was a Goal Attainment Scale (GAS) rated by parents and kindergarten teachers. Secondary outcomes include parent/teacher-reported communication skills (Escala de Avaliação de Competências Comunicativas) and an assessment of the child’s general language ability (Teste de Linguagem—Avaliação da Linguagem Pré-Escolar). Results: GAS results show that all the children in the intervention group made progress. Statistically significant differences between pre- and post-intervention assessments were found for all secondary outcomes. Conclusions: The main findings suggest that the PICP improves language in preschool-age children with ASD and DLD with pragmatic difficulties. Further research is needed to analyse the effects of the PICP for each neurodevelopmental disorder individually. These results are crucial and will contribute to future research and evidence-based practice.

ABSTRACT The use of robust sample methodologies to estimate the highest number of species with different ecological requirements and traits is essential to the knowledge construction of the biodiversity and to establish wildlife assessment and monitoring programs. Our aims were to study the performance of colored pan traps in the capture of Drosophilidae (Diptera), a method never used for sampling this taxon. During six months, colored pan traps (blue, yellow and white) were tested in three areas in Southern Brazil. We captured 375 individuals of 30 species belonging to four genera of Drosophilidae. The most abundant species were Drosophila lutzii (n=215) p=0.58, Scaptomyza sp. (n=55) p=0.15 and D. bromelioides (n=17) p=0.04, all of them, anthophilous species. All colored pan traps captured a high quantify species of Drosophilidae, mainly anthophilous species.

Abstract Allium sativum L. is an herb of the Alliaceae family with a specific taste and aroma and medicinal and nutraceutical properties that are widely marketed in several countries. Brazil is one of the largest importers of garlic in the world, despite of its production is restricted and limited to internal consumption. Thus, explore the genetic diversity of commercial garlic conserved at germplasm banks is essential to generate additional genetic information about its economically important crop. A suitable tool for this purpose is the cytogenetic characterisation of these accessions. This study aimed to characterise the cytogenetic diversity among seven accessions of garlic from a Germplasm Bank in Brazil. The karyotypes were obtained by conventional staining and with chromomycin A3 (CMA) and 4,6-diamidino-2-phenylindole (DAPI) fluorochromes. All accessions analysed showed chromosome number 2n = 16, karyotype formula 6M+2SM, symmetrical karyotypes, reticulate interphase nuclei, and chromosomes with uniform chromatin condensation from prophase to metaphase. The fluorochromes staining showed differences in the amount and distribution of heterochromatin along the chromosomes and between accessions studied. Based on the distribution pattern of these small polymorphisms, it was possible to separate the seven accessions into three groups. It was also possible to differentiate some of the accessions individually. One of the results obtained showed a heteromorphic distension of the nucleolar organiser region observed on the chromosome pairs 6 or 7 with peculiar characteristics. It was suggested for example, that the heteromorphic block of heterochromatin (CMA+++/DAPI-) on chromosome 6 of the “Branco Mineiro Piauí” accession can be used as a marker to identify this genotype or may be associated with some character of economic interest.

Spermacoce latifolia presents wide dispersion in the Brazilian regions producing grains. The knowledge about the dormancy in weeds helps to understand the population dynamics and the efficient management. The present study had as objective to evaluate different treatments for overcoming dormancy of seeds. Nine treatments to overcome dormancy was used and the control, without treatment. After these, germination, germination first count and germination speed index tests were performed. A completely randomized design was used with four repetitions. Sandpaper 1' and 1% KNO3 shown the higher viability and vigor values. For G, FC and GSI, to the treatment seeds exposure to heat 60 °C there was no statistical difference comparing to the control, while the treatment seed exposure to heat 40 °C obtained results smaller than all other treatments, except those who used the H2SO4. For the seeds submitted to the treatments with H2SO4 for one and two minutes of immersion, there was no formation of seedlings. The treatments using the friction of seed in sandpapers for 1 minute and the immersion for 12 hours in KNO3 solution (1%) were efficient in overcoming dormancy of Spermacoce latifolia seeds. There are three possible causes of dormancy in this species: mechanical resistance of the cover to embryo growth, impermeability of the cover to the water and gas and imbalance between promoter and inhibitory substances to germination.

This case report aims to describe the occurrence of negative impacts of wearing nose-flap devices on beef calves subjected to the two-stage weaning method. Forty-one calves, twenty-one pure Nellore and twenty F1 Angus-Nellore, were weaned on average at 236 days of age. Commercial nose-flap devices were fitted in the nostrils of the calves (d0) to prevent suckling and removed five days later (d5). Individual body weights were assessed at d0 and d5, and average daily gain (ADG) was calculated. At d5, during nose-flap device removal, it was noted that 26.8% of the calves lost the nose-flap device; however, all of them had wounds in their nostrils (no injuries in the nostrils had been observed on d0). To assess the severity of these injuries, an impairment score was assigned to each calf, ranging from 1 = no lesions to 5 = injured with purulent discharge. A logistic regression model was fitted to evaluate the effect of sex and genetic group on nose-flap retention (kept or lost). The retention rate did not differ (p > 0.05) between sex and genetic groups. All calves showed at least open wounds of the nasal septum (score 2), including those that lost the nose-flaps before d5. Almost half of the calves showed weight loss during this period. We conclude that there is a considerable risk of the two-stage weaning method compromising the physical integrity of the nostrils of beef calves through the use of these devices, and due to this, it should not be referred to as a low-stress weaning practice for beef calves.

[This corrects the article DOI: 10.1371/journal.pone.0244532.].

BackgroundSeveral studies have investigated the acoustic effects of diagnosed anxiety and depression. Anxiety and depression are not characteristics of the typical aging process, but minimal or mild symptoms can appear and evolve with age. However, the knowledge about the association between speech and anxiety or depression is scarce for minimal/mild symptoms, typical of healthy aging. As longevity and aging are still a new phenomenon worldwide, posing also several clinical challenges, it is important to improve our understanding of non-severe mood symptoms' impact on acoustic features across lifetime. The purpose of this study was to determine if variations in acoustic measures of voice are associated with non-severe anxiety or depression symptoms in adult population across lifetime.MethodsTwo different speech tasks (reading vowels in disyllabic words and describing a picture) were produced by 112 individuals aged 35-97. To assess anxiety and depression symptoms, the Hospital Anxiety Depression Scale (HADS) was used. The association between the segmental and suprasegmental acoustic parameters and HADS scores were analyzed using the linear multiple regression technique.ResultsThe number of participants with presence of anxiety or depression symptoms is low (>7: 26.8% and 10.7%, respectively) and non-severe (HADS-A: 5.4 ± 2.9 and HADS-D: 4.2 ± 2.7, respectively). Adults with higher anxiety symptoms did not present significant relationships associated with the acoustic parameters studied. Adults with increased depressive symptoms presented higher vowel duration, longer total pause duration and short total speech duration. Finally, age presented a positive and significant effect only for depressive symptoms, showing that older participants tend to have more depressive symptoms.ConclusionsNon-severe depression symptoms can be related to some acoustic parameters and age. Depression symptoms can be explained by acoustic parameters even among individuals without severe symptom levels.

Metabolites, substrates or products of metabolic processes, are involved in many biological functions, such as energy metabolism, signaling, stimulatory and inhibitory effects on enzymes and immunological defense. Metabolomic phenotypes are influenced by combination of genetic and environmental effects allowing for metabolome-genome-wide association studies (mGWAS) as a powerful tool to investigate the relationship between these phenotypes and genetic variants. The objectives of this study were to estimate genomic heritability and perform mGWAS and in silico functional enrichment analyses for a set of plasma metabolites in Canadian crossbred beef cattle. Thirty-three plasma metabolites and 45,266 single nucleotide polymorphisms (SNPs) were available for 475 animals. Genomic heritability for all metabolites was estimated using genomic best linear unbiased prediction (GBLUP) including genomic breed composition as covariates in the model. A single-step GBLUP implemented in BLUPF90 programs was used to determine SNP P values and the proportion of genetic variance explained by SNP windows containing 10 consecutive SNPs. The top 10 SNP windows that explained the largest genetic variation for each metabolite were identified and mapped to detect corresponding candidate genes. Functional enrichment analyses were performed on metabolites and their candidate genes using the Ingenuity Pathway Analysis software. Eleven metabolites showed low to moderate heritability that ranged from 0.09 ± 0.15 to 0.36 ± 0.15, while heritability estimates for 22 metabolites were zero or negligible. This result indicates that while variations in 11 metabolites were due to genetic variants, the majority are largely influenced by environment. Three significant SNP associations were detected for betaine (rs109862186), L-alanine (rs81117935), and L-lactic acid (rs42009425) based on Bonferroni correction for multiple testing (family wise error rate

Functional and enduring mammary structure is pivotal for producer profitability, and animal health and welfare in beef production. Genetic evaluations for teat and udder score in Canadian Angus cattle have previously been developed. The aim of this study was to identify genomic regions associated with teat and udder structure in Canadian Angus cows thereby enhancing knowledge of the biological architecture of these traits. Thus, we performed a weighted single-step genome wide association study (WssGWAS) to identify candidate genes for teat and udder score in 1,582 Canadian Angus cows typed with the GeneSeek® Genomic Profiler Bovine 130K SNP array. Genomically enhanced estimated breeding values (GEBVs) were converted to SNP marker effects using unequal variances for markers to calculate weights for each SNP over three iterations. At the genome wide level, we detected windows of 20 consecutive SNPs that explained more than 0.5% of the variance observed in these traits. A total of 35 and 28 windows were identified for teat and udder score, respectively, with two SNP windows in common for both traits. Using Ensembl, the SNP windows were used to search for candidate genes and quantitative trait loci (QTL). A total of 94 and 71 characterized genes were identified in the regions for teat and udder score, respectively. Of these, 7 genes were common for both traits. Gene network and enrichment analysis, using Ingenuity Pathway Analysis (IPA), signified key pathways unique to each trait. Genes of interest were associated with immune response and wound healing, adipose tissue development and morphology, and epithelial and vascular development and morphology. Genetic architecture from this GWAS confirms that teat and udder score are distinct, polygenic traits involving varying and complex biological pathways, and that genetic selection for improved teat and udder score is possible.

This paper discusses a rapid and sensitive method developed to determine trace levels of mercury in natural water samples by cold vapor atomic absorption spectrometry using a preconcentration system composed by mini-column packed with 100 mg of 2-aminothiazol modified silica gel (SiAT) coupled on-line with the spectrometer’s cold vapor generator system. The optimum preconcentration conditions are also described here. The preconcentrated Hg(II) ions were eluted directly from the column to the spectrometer’s cold vapor generator system using 100 μL of 2 mol L -1 hydrochloric acid and the retention efficiency achieved exceeded 95%. The enrichment factors determined were 29, 38 and 46 using 3, 4 and 5 mL of preconcentrated aqueous solutions containing 400 ng L -1 of Hg. The detection limit calculated was 5 ng L -1 . The preconcentration procedure was applied to determine trace level mercury in spiked river water samples.

The lability of Cd(II), Cr(III), Cu(II), Mn(II) and Pb(II) complexed by humic substances (HSs) was investigated by means of ion exchange on cellulose modified with p-aminobenzoic groups (Cell-PAB), using a batch procedure. The HSs were extracted from water samples using adsorption in a column packed with XAD 8 resin. The metal-HS complexes were prepared by adding solutions containing all the aforementioned metal ions ( Cd(II), Cr(III), Cu(II), Mn(II) and Pb(II) ). The results indicated that the distribution coefficients (Kd) of Cell-PAB decreased with the presence of HSs, and that the lability of metal fractions complexed by HSs decreases in pH values > 4.0, complexation time > 10 h and HS concentration > 500 mg L -1 . The metal exchange between HSs and Cell-PAB exhibited the following order of metal ion lability: Cd < Pb < Mn ≅ Cr < Cu.

The main goal of the present work was to determine the nutraceutical potential of Asparagopsis taxiformis D. extracts from Madeira Archipelago south coast. Extraction methodologies consisted either/or in 72 hours stirring, at room temperature (M1), or 6 cycles of Soxhlet extraction (M2), both with re-extraction. Solvents used were distilled water, ethanol, methanol and ethyl acetate. M1 allowed to obtain the highest values for extraction yield (31.65 g.100g−1 dw) using water, whereas iodine content (3.37 g.100g−1 dw), TPC (1.71 g GAE.100g−1 dw) and chlorophyll a (45.96 mg.100g−1 dw) were obtained using ethanol, and TCC (36.23 mg.100g−1 dw) with methanol. Extracts that showed higher reduction activity in M1 were derived from ethanol extraction (1,908 mg AAE.100g−1 dw). Water and ethanol were the best solvents for higher DPPH scavenging activity in M2, both with same result (IC50 1.37 mg.mL−1). The lowest value of IC50 for chelating activity (1.57 mg.mL−1) was determined in M1, using ethyl acetate. The remaining residue was used to obtain other products, i.e. lipid extraction (M1, 2.05 g.100g−1 dw), carrageenans (M2, 21.18 g.100g−1 dw) and cellulose (M1, 23.81 g.100g−1 dw) with subsequent FTIR ATR analysis. Our results show that A. taxiformis is a valuable source of bioactive compounds. The M1 extraction methodology using ethanol is the most effective solvent to produce an iodine rich bioactive extract with potential of being used as a nutraceutical supplement. Also, we have demonstrated a possible downstream strategy that could be implemented for multiple compound extraction from A. taxiformis residue. This has a vital importance for future feasibility, when using this biomass as an industrial feedstock for multiple products production. Statistical analysis, using SPSS 24.0, was also performed and important correlations were found between assays and methods.

Looking at the long-time behaviour of a dam, it is necessary to assume that the water can penetrate a possible crack washing away some components of the concrete. This type of corrosion reduces the tensile strength and fracture energy of the concrete compared to the same parameters measured during a short-time laboratory test. This phenomenon causes the so called sub-critical crack propagation. That is the reason why the International Commission of Large Dams recommends to neglect the tensile strength of the joint between the dam and the foundation, which is the weakest point of a gravity dam. In these conditions a shear displacement discontinuity starts growing in a point, called Fictitious Crack Tip (shortened FCT), which is still subjected to a compression stress. In order to manage this problem, in this paper the cohesive crack model is re-formulated with the focus on the shear stress component. In this context, the classical Newton-Raphson method fails to converge to an equilibrium state. Therefore the approach used is based on two stages: (a) a global one in which the FCT is moved ahead of one increment; (b) a local one in which the non-linear conditions occurring in the Fracture Process Zone are taken into account. This two-stage approach, which is known in the literature as a Large Time Increment method, is able to model three different mechanical regimes occurring during the crack propagation between a dam and the foundation rock.