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The objective of this study was to evaluate the 305-day cumulative milk yield (MY305) and the lactation curve trajectory of cows from different genetic groups originating from the crossing of Holstein and Dairy Gyr breeds, daughters of proven and unproven sires. Milk yield records of 1,032 animals with a genetic composition of ½, ¾ and ⅞ Holstein x Gyr were used. The analyses to determine the effects of the genetic groups on the shape of the lactation curve were carried out in two steps: 1) pre-adjusting test-day milk yields for fixed effects in a linear model, and 2) using the adjusted yields in a nonlinear model on days in milk to compare the lactation curves of animals from different genetic groups, born to proven and unproven sires. The effects included in the linear model for pre-adjustment of test-day yields were the contemporary group and age class of cow at calving. The data were analyzed by the least squares method. The same model was used for MY305, which included the effects of genetic group of the animal and sire category (proven or unproven). MY305 was influenced by all effects (P

Objetivou-se com este estudo verificar a existência de associações genéticas entre características de carcaça e características andrológicas em touros Nelore jovens. Realizou-se avaliação andrológica e da carcaça de 223 machos Nelore com média de 21 meses de idade. Para estimação dos parâmetros genéticos utilizou-se a inferência bayesiana por meio do software THRGIBBS1F90. As estimativas de herdabilidade obtidas para DEFMAI, DEFMEN, DEFTOT, AR, AOL, EG e P8 foram 0,33; 0,20; 0,21; 0,35; 0,32; 0,28 e 0,29, respectivamente. As estimativas de correlação genética de DEFTOT com AOL, EG e P8 foram –0,46; –0,28 e –0,19, respectivamente; já de AR com estas mesmas características foram –0,60; –0,03 e –0,12, respectivamente. Os resultados obtidos neste estudo demonstram haver resposta correlacionada favorável entre as características reprodutivas e de carcaça estudadas.

Dispersivity and porosity parameters needed to simulate flow and non-reactive transport were calculated and validated for loess-like sediments of the Pampean aquifer located in southeastern Buenos Aires province, Argentina, using infiltration experiments in laboratory columns filled with selected undisturbed sediment. To obtain values for these parameters, the experimental curves of arrival for chloride were visually adjusted to the curves obtained from numerical simulation using PHREEQC 2.0. Visual adjustment consisted of trying different parameter values until the most representative one was obtained. The best adjustment was obtained for dispersivity and porosity values of 0.01 m and 0.35, respectively. Since analytical solutions for the flow and transport equations are applicable to simplified cases such as this, an attempt was made to adjust the parameters automatically, using a model based on this type of solution. This automated analytical solution was developed using the Fortran programming language, and the automatic parameter calibration was achieved by minimizing the distance between the observed and calculated values of two parameters. The automated technique gave values of 0.0084 m and 0.39 for dispersivity and porosity, respectively. The sediments studied here constitute the uppermost unit of the Pampean aquifer. Given the relevance of this layer and the growing anthropic influence on it, parameter quantification is important for both laboratory tests and for hydrogeochemical simulations that investigate contaminant transport.

This article reviews the use of several classes of antihypertensive drugs in elderly hypertensive patients who may also have one of eight concomitant medical conditions. Specific contraindications in various disease states as well as preferred choice(s) of drugs exist. The rationale for drug choice is supported by explanations that relate to the pathophysiology of hypertension in the elderly population and the disease under consideration.

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Repeated measurements (RM) are common in forage experiments. The data used in this study were accumulated ammonia losses by volatilization (N)and dry matter production (DM) of cynodon dactylon cv. Coastcross pasture from an experiment in blocs with five levels of urea: 0,25, 50, 100 and 200 kg of N ha , applied in five periods (Cuttings). For N, RM were the averages of cuttings and nine days of observation. The F test for the hypothesis of no affect for period and level x period interaction (DM) and for days interaction was not affected by univariate and multivariate tests. However, greenhouse-geisser epsilon estimate was biased downwards. Polynomial contrast in univariate ANOVA and logistic function agreed explaining acumulated N. For DM, uneaqual population variances on different was rejected and the assumption that pairs of observations on the same subject are equally correladet was rejected. Made available in DSpace on 2022-04-12T11:00:56Z (GMT). No. of bitstreams: 1 RepeatedMesurementAnalyses.pdf: 652492 bytes, checksum: f76a150a09b6463e3f193cb357fb9696 (MD5) Previous issue date: 2001