The potential to recover bioenergy from anaerobic digestion of water hyacinth (WH) and from its co-digestion with fruit and vegetable waste (FVW) was investigated. Initially, biogas and methane production were studied using the biochemical methane potential (BMP) test at 2 g volatile solids (VS) L(-1) of substrate concentration, both in the digestion of WH alone and in its co-digestion with FVW (WH-FVW ratio of 70:30). Subsequently, the biogas production was optimized in terms of total solids (TS) concentration, testing 4 and 6% of TS. The BMP test showed a biogas yield of 0.114 m(3) biogas kg(-1) VSadded for WH alone. On the other hand, the biogas potential from the WH-FVW co-digestion was 0.141 m(3) biogas kg(-1) VSadded, showing an increase of 23% compared to that of WH alone. Maximum biogas production of 0.230 m(3) biogas kg(-1) VSadded was obtained at 4% of TS in the co-digestion of WH-FVW. Using semi-continuously stirred tank reactors, 1.3 m(3) biogas yield kg(-1) VSadded was produced using an organic loading rate of 2 kg VS m(-3) d(-1) and hydraulic retention time of 15 days. It was also found that a WH-FVW ratio of 80:20 improved the process in terms of pH stability. Additionally, it was found that nitrogen can be recovered in the liquid effluent with a potential for use as a liquid fertilizer.

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En 191 individuos de la raza bovina criolla Hartón del Valle, se evaluó la infección por los protozoarios Babesia bovis y Babesia bigemina mediante PCR convencional, los polimorfismos del gen BoLA-DRB3,2* mediante PCR-SBT y la asociación entre ambos (Odds Ratio, OR). Los alelos fueron categorizados según su asociación en resistentes (R), susceptibles (S) o neutrales (N) a la infección y los individuos genotipados según la clasificación de sus alelos como: N/N, N/R, N/S, R/R, R/S y S/S. Ningún animal fue positivo a la infección por B. bovis y por tanto no se realizaron estimaciones de asociación. La infección con B. bigemina fue del 13,1%. Se encontraron 36 alelos BoLA-DRB3,2, los más frecuentes fueron el *1101 (0,196), *20012 (0,097), *2006 (0,053) y *2703 (0,053). Se encontró una asociación positiva (p