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The objective was to estimate direct and maternal heritability of weaning weight at 7 mo of age (WW), and the final weight at 18 mo (FW) and breeding values and genetic trends for WW and FW in Zebu bermejo cattle of Cuba. A bi-character animal model was used in 5,120 records of WW and 1,134 of FW. The animals were born between 1982 and 2008 in three herds. The statistical model for WW included the effects of the group of contemporaries (herd-year-birth season-sex, age at weaning as linear co-variable and age of the mother as linear and quadratic covariable), random effect of the animal, random maternal effect, permanent environmental effect and the error. The model for FW included the group of contemporaries (herd-year-birth season) age at final weight as linear co-variable, random effect of the animal, permanent environmental effect and the error. Genetic tendencies were estimated by linear regression of the average additive genetic value on the birth years from 1982 to 2007. The heritability estimated for the WW were 0.11±0.04 and 0.03±0.02 (direct and maternal effects, respectively), with a genetic correlation of -0.15±0.24 between these effects. The heritability for the FW was 0.28±0.10. Genetic tendencies were positive and significant for direct effects of PD (0.102 kg) and PF (0.244 kg). It is concluded that the heritability of the direct and maternal effects of the WW were low and that the FW has a moderate heritability that can favor the response to selection in breeding programs. [ABSTRACT FROM AUTHOR]

El objetivo de este trabajo fue estimar componentes de (co)varianza de caracteres reproductivos y su relación genética con el peso al destete (PD) en el ganado Cebú de Cuba. Se utilizaron datos de 51,193 partos de 17,890 vacas paridas entre 1981 y 2000 en 48 hatos. El pedigrí incluyó 23,903 individuos. Para estimar las correlaciones genéticas entre el PD y los caracteres reproductivos se utilizaron 67,829 registros, 19,768 fueron para PD y 48,061 para rasgos reproductivos. Se aplicaron modelos univariados y bivariados con el procedimiento REML y utilizando el programa ASREML. La heredabilidad para las variables reproductivas fue baja (0.01 a 0.09). Las correlaciones genéticas entre días abiertos (DA) fueron altas entre los tres primeros partos (0.92 a 0.99) y menores entre estos y los posteriores (0.45 a 0.90). Las correlaciones genéticas entre los DA y el intervalo a la primera inseminación, intervalo entre partos y servicios por gestación fueron de 0.98, 0.99 y 0.39, respectivamente. Las correlaciones genéticas del PD con los rasgos reproductivos señalados variaron de 0.04 a 0.07. Se concluye que la heredabilidad estimada para los caracteres reproductivos fue baja, las correlaciones genéticas entre ellos por lo general fueron altas, y su correlación genética con el peso al destete fue baja. [ABSTRACT FROM AUTHOR]

The objective of this study was to estimate (co)variance components for reproductive traits and genetic correlations with weaning weight (WW) in Zebu cattle in Cuba. Data for 51,193 calvings of 17,890 cows in 48 herds were used. The pedigree file included 23,903 individuals. In order to estimate genetic correlations between WW and reproductive traits, 67,829 records were used, of which 19,768 were for WW and 48,061 for reproductive traits. Univariate and bivariate models were applied using the REML procedure of the ASREML program. Heritability for reproductive traits was low (0.01 to 0.09). Genetic correlations between days open (DO) were high only for the first three births (0.92 to 0.99) and low between these and later ones (0.45 to 0.90). Genetic correlations between DO and calving to first insemination interval, calving interval and number of inseminations for pregnancy were 0.98, 0.99 and 0.39, respectively. Genetic correlations of WW with reproductive traits varied between 0.04 and 0.07. As a conclusion, estimated heritability for reproductive traits was low, genetic correlations among reproductive traits were high and its genetic correlation with weaning weight was low. [ABSTRACT FROM AUTHOR]

Anadara tuberculosa is one of the most abundant mollusks of commercial importance in Costa Rica. Its habitat water is a potential source of fecal and chemical contamination to humans. We wanted to asses enterovirus, mainly poliovirus and hepatitis A virus and chemicals such as sulphates and nitrates in meat and body fluids. Thirteen samples were taken from four sites in Nicoya Gulf, three sites in the Sierpe-Térraba mangrove (Pacific of Costa Rica) and from five fish markets in San José, the capital of Costa Rica. Samples were tested for 1) fecal coliforms (Most Probable Number/100 ml), 2) isolation of enterovirus in cell culture (Hep-2, FrhK-4), 3) cell cytotoxicity in Vero cells and 4) the ability to inactivate 10 ID50% of poliovirus in cell culture. The Most Probable Number/100 ml in surrounding water was higher than the accepted standard for recreational waters, although the number of fecal coliforms in meats and body fluids was lower than in the external water. No cytopathogenic agents were isolated, but we found nitrate and sulphate concentrations that exceeded maxima for human consumption and recreation. The intrinsic cytotoxicity of the samples was at a 1/8 dilution, but some samples were cytotoxic at dilutions of 1/128. Body fluids were more cytotoxic than meats, but a positive correlation between cytotoxicity and chemical contamination was not determined: apparently other pollutants not identified in this study were responsible. Fluid and meat capacity to inactivate 10 ID50% of poliovirus in cell culture was demonstrated. Samples that were toxic for cell cultures also showed a higher percentage of poliovirus inactivation. Monitoring chemical pollution in these waters is highly recommended.