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    Item type:Publication,
    Ecuadorian Holstein-Friesian cattle paternal lineages: Demographic structure, inbreeding evolution, and genetic diversity
    (Public Library of Science (PLoS), 2025-02-25)
    Luis F. Cartuche Macas
    ;
    Miguel A. Gutierrez Reinoso
    ;
    Edilberto Chacón
    ;
    Carlos O. Larrea Izurieta
    ;
    Holstein-Friesian cattle are the most important dairy breed worldwide. The main objective was to carry out a detailed pedigree evaluation of the Ecuadorian Holstein-Friesian cattle to investigate the demographic structure, inbreeding evolution, and genetic diversity of the official paternal lineages to determine the potential GD loss after the inclusion of modern Assisted Reproductive Technologies (ARTs). Official pedigree information from 28,893 Holstein-Friesian sires born between 1950 and 2021 and enrolled with the Ecuadorian Holstein-Friesian Association (AHFE, Ecuador) were recorded and evaluated from USA and Canada genetic official databases. After multiple-trait across-country genetic analyses the total population was divided into four subpopulations; i) 1950–1969: natural mating (NM) period; ii) 1970–1989: NM +  artificial insemination (AI) period; iii) 1990–2009: AI +  embryo transfer (ET) period; and iv) 2010–2021: AI +  ET +  genomic selection (GS) period. Demographic parameters [number of males, pedigree integrity (PI), and generation interval (GI)] were analysed. PI was analysed using known ancestors up to 4 generations considering the number of complete (GCom), maximum (GMax) and equivalent (GEqu) generations. Moreover, Inbreeding parameters [inbreeding coefficient (F), average relatedness (AR), coancestry (C), effective size (Ne), genetic conservation index (GCI)] and parameters related to the gene origin probability (number of founders (f), effective number of founders (fe), genetic conservation index (GCI), among others] were also analysed, together with the fe/f ratio, fge/fe ratio, genetic contributions, and genetic diversity loss (GD-loss) derived parameters. The results indicated that nearly all imported sires used in Ecuador born in the beginning of 1990s could be traced to just three countries, who together account for > 90% of paternal lineages. This fact indicates that GD has undergone a dramatic decrease during the past 30 years. The PCI for the three last periods were > 55%, and the trend was enhanced in the fourth chronological period till > 92%. The estimated proportion of random genetic drift in GD loss increased over time as well as the Ne that decreased by the time. In conclusion, the occurrence of AI +  ET +  GS period led to the major GD loss. Therefore, due to the extremely limited number of paternal lineages the strategy for recovering the minimal GD on the current and future Ecuadorian Holstein-Friesian cattle should reduce the inbreeding values by increasing the Ne using alternately the foreign genetic material and the national breeding stock.
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    Item type:Publication,
    Eco-alternative treatments for Vibrio parahaemolyticus and V. cholerae biofilms from shrimp industry through Eucalyptus (Eucalyptus globulus) and Guava (Psidium guajava) extracts: A road for an Ecuadorian sustainable economy
    (Public Library of Science (PLoS), 2024-08-13)
    Nicolás Renato Jara-Medina
    ;
    Dario Fernando Cueva
    ;
    Ariana Cecibel Cedeño-Pinargote
    ;
    Arleth Gualle
    ;
    Daniel Aguilera-Pesantes
    Understanding how environmental variables influence biofilm formation becomes relevant for managing Vibrio biofilm-related infections in shrimp production. There fore, we evaluated the impact of temperature, time, and initial inoculum in the biofilm development of these two Vibrio species using a multifactorial experimental design. Planktonic growth inhibition and inhibition/eradication of Vibrio biofilms, more exactly V. parahaemolyticus (VP87 and VP275) and V. cholerae (VC112) isolated from shrimp farms were evaluated by Eucalyptus and Guava aqueous leaf extracts and compared to tetracycline and ceftriaxone. Preliminary results showed that the best growth conditions of biofilm development for V. parahaemolyticus were 24 h and 24̊C (p <0.001), while V. cholerae biofilms were 72 h and 30̊C (p <0.001). Multivariate linear regression ANOVA was applied using colony-forming unit (CFU) counting assays as a reference, and R-squared values were applied as goodness-of-fit measurements for biofilm analysis. Then, both plant extracts were analyzed with HPLC using double online detection by diode array detector (DAD) and mass spectrometry (MS) for the evaluation of their chemical composition, where the main identified compounds for Eucalyptus extract were cypellogin A, cypellogin B, and cypellocarpin C, while guavinoside A, B, and C compounds were the main compounds for Guava extract. For planktonic growth inhibition, Eucalyptus extract showed its maximum effect at 200 μg/mL with an inhibition of 75% (p < 0.0001) against all Vibrio strains, while Guava extract exhibited its maximum inhibition at 1600 μg/mL with an inhibition of 70% (p < 0.0001). Both biofilm inhibition and eradication assays were performed by the two conditions (24 h at 24̊C and 72 h at 30̊C) on Vibrio strains according to desirability analysis. Regarding 24 h at 24̊C, differences were observed in the CFU counting between antibiotics and plant extracts, where both plant extracts demonstrated a higher reduction of viable cells when compared with both antibiotics at 8x, 16x, and 32x MIC values (Eucalyptus extract: 1600, 3200, and 6400 μg/mL; while Guava extract: 12800, 25600, and 52000 μg/mL). Concerning 72 h at 30̊C, results showed a less notorious biomass inhibition by Guava leaf extract and tetracycline. However, Eucalyptus extract significantly reduced the total number of viable cells within Vibrio biofilms from 2x to 32x MIC values (400–6400 μg/mL) when compared to the same MIC values of ceftriaxone (5–80 μg/mL), which was not able to reduce viable cells. Eucalyptus extract demonstrated similar results at both growth conditions, showing an average inhibition of approximately 80% at 400 μg/mL concentration for all Vibrio isolates (p < 0.0001). Moreover, eradication biofilm assays demonstrated significant eradication against all Vibrio strains at both growth conditions, but biofilm eradication values were substantially lower. Both extract plants demonstrated a higher reduction of viable cells when compared with both antibiotics at 8x, 16x, and 32x MIC values at both growth sets, where Eucalyptus extract at 800 μg/mL reduced 70% of biomass and 90% of viable cells for all Vibrio strains (p < 0.0001). Overall results suggested a viable alternative against vibriosis in the shrimp industry in Ecuador.