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Abstract. This study was carried out to determine morphometric and meristic characteristics of two populations (wild and cultured) of Cichlasoma festae and to establish whether populations could be discriminated based on morphometric variability. Twenty-two morphometric and four meristic characters were used to test the hypothesis differentiation. Univariate analysis of variance (ANOVA) from 100 adult specimens showed significant differences (p < 0.05) for 21 standardized morphometric measurements out of 26 characters among the means of the wild and cultured Cichlasoma festae populations tested. Cross correlation amongst certain morphometric variables (i.e. body weight, total length, standard length, pre-ventral length, AC1, LC1 and P1) were medium-strong (r ≥ 0.5), while the remaining were weakly correlated (r < 0.5). The length-weight relationship parameter b and condition factor (K) values were respectively 2.21 and 1.97 (indicating allometric growth) for cultured fish groups and 2.86 and 4.07 (p < 0.05) for wild fish groups. The condition factor values were significantly different from each other and showed that feeding of cultured fish should be improved. Both groups were accurately separated (> 80 % success rate) by linear discriminant functions that included only four morphometric measures.

Relational coordination model has been applied to different sectors reaching positive results in terms of performance. In this research, the relational coordination model has been applied to prove high levels of teacher satisfaction in e-learning. According to the model, organizations can achieve performance by providing frequent, timely and problem solving communication mechanisms to support shared knowledge, in a context of shared goals and mutual respect. We have surveyed teachers who teach online courses in Spanish universities and companies, on these particular issues. By using Structural Equation Model analysis we have shown that higher standards in terms of relational coordination among teachers in e-learning explain higher degrees of satisfaction. The conclusions should be considered by policy makers and managers when they evaluate alternatives for the improvement of performance in online education.

To evaluate dierent methods of estimating bovine carcass composition, seventy yearling bulls of the``Asturiana de los Valles'' beef breed were slaughtered and their carcass composition estimated by a commercial dissection of the right half-carcass and by tissular dissection of the 6th and 10th rib of the left half-carcass. Correlation and regression analyses were used to identify the most accurate predictors of carcass composition. In simple regression, the percentage of lean in the 10th rib was the most accurate predictor (r=0.88; P<0.001) of the lean proportion in the carcass and the percentage of fat in the 6th rib was the best predictor (r=0.90; P<0.001) of the carcass fat content. The correlation coecients for estimating the bone percentage in the carcass from the bone proportion in the ribs (6th and 10th) were low (r=0.63 and 0.51 respectively), although signi®cant (P<0.001) and the coecient improved when the proportion of lean in the ribs was used as predictor (r=0.78 and 0.70 for the 6th and the 10th rib respectively). In multiple regression, the addition of more regressors of the rib composition and carcass traits, such as carcass hot weight, the carcass fatness score and the weight of the kidney knob and channel fat, led to an improvement (P<0.05) in accuracy for some predictions. The results in general show that the accuracy of the predictions for the carcass composition obtained from dissection of both the 6th and 10th ribs was similar, although the dissection of the 10th rib tended to overestimate the proportion of fat in the carcass. Therefore, considering the carcass quartering method for the extraction of the ribs, it is proposed that dissection of the 6th rib is more appropriate than dissection of the 10th rib so as not to reduce the carcass value and obtain a good estimate of the carcass composition. #