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Copyright of Revista Mexicana de Ciencias Agrícolas is the property of Instituto Nacional de Investigaciones Forestales, Agricolas y Pecuarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The alveolar fricative consonant /s/in plosive position (middle and end of the word) was studied in a sample composed by 161 speakers of Chilean Spanish, divided in four age groups from 2;0 up to 3;11. The main purpose of the study was to consider this segment from a dialectal perspective, in order to understand at what point in its acquisition children start to use this sound's variants, i.e., [h] and [Ø]. Results were analyzed according to age and socioeconomic status variables. [ABSTRACT FROM AUTHOR]

The prototype of Pura Raza Española horse depends on the equestrian disciplines and establishes the breeding selection objectives; the selection criteria are developed from zoometric measures (ZM), which are subject to multiple direct and maternal genetic effects. The objective of this study was to evaluate the magnitude of the maternal genetic effects, based on the (co)variances, if they are equal to or different from zero. Our database included information of 1806 equines born from 2004 to 2013, with data of eight ZM (mean in cm ± SD): thoracic perimeter (TP; 189.3±8.9), knee perimeter (KP; 32.3±1.8), cannon perimeter (CP; 20.4±1.3), scapular-ischial length (SIL; 160.7±5.9), chest width (CW; 43.1±3.0), height of the substernal space (HSS; 83.1±5.1), chest height (CH; 73.2±4.3), and withers height (WH; 157.8±4.3). We conducted the analysis with a mixed model that included the fixed effects of contemporary groups (ranch, year, time, and sex) and the age covariable of the individual; as random, the direct (D) and maternal (M) genetic effects, plus the covariance between them, (C). By alternating maternal genetic effects, we compared the models: D, DM, and DMC. We selected the models using the likelihood-ratio test. The pedigree was made up of 7498 animals. We estimated the direct (h²) and maternal (m²) heritabilities, as well as the genetic correlations (rg). For the analysis, we used the software MTDFREML. The maternal genetic effects in CH and CP were statistically not different from zero (p±0.05); in the other ZM, the DMC model was the most fit. The h² oscillated between 0.09 (CH) and 0.65 (WH), with an average of 0.40. The m² fluctuated between 0.17 (HSS) and 0.23 (WH), with an average of 0.19. All the rg were negative, between ±0.37 (WH) and ±0.99 (HSS), which must be considered in the genetic improvement of the ZM. [ABSTRACT FROM AUTHOR]

Copyright of Rodriguésia is the property of Revista Rodriguesia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mexican Journal of Biotechnology is the property of Sociedad Cientifica Internacional de Biotecnologos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pinus pseudostrobus Lindl. is the pine species of major economic importance in the state of Michoacan. For its conservation and sustainable management both the variation of quantitative traits with adaptive value as well as the genetic diversity through markers neutral to selection should be known. In the present study the genetic isoenzymatic variation among populations of P. pseudostrobus along an altitudinal gradient (2200- 2910 m of altitude) in the state of Michoacan, Mexico was investigated. In January 2001, seeds from eight locations, separated by 100 m altitude were collected; in each population from 9 to11 trees were randomly selected. Polymorphism was found in 12 of the 14 loci examined. The expected average heterozygosity (He) was 0.10. In all loci Hardy-Weinberg equilibrium was found. Genetic differentiation among populations was significant (FST = 0.017), although it was low. Average genetic distance (0.078) was low, and average gene flow was high (Nm =14.5). It was found a weak pattern of genetic variation associated with altitude of origin of populations, in which lower altitude populations presented a greater effective number of alleles than higher altitude populations. To preserve genetic diversity it is suggested to establish three Forest Genetic Resource Conservation Units (FGRCU), one for each of the following altitudinal ranges, with the minimum size of a viable effective population (Ne) as follows: between 2100 and 2400 m with 3422 individuals in reproductive age, between 2400 and 2700 m with 1586 individuals, and 2700 and 3000 m with 2321 individuals. [ABSTRACT FROM AUTHOR]

The aim of the study was to analyze the impact of environmental factors as well as to estimate components of (co) variance of reproductive traits in Chacuba cattle. For that, 4,957 records of cows, daughters of 893 dams and 110 sires were used. Models that considered number of parity, calf sex, and contemporary group (herd-year-season of calving) as fixed effects were tested. The season of calving was included as every two, three, four and six months. The interval from calving to conception (ICC), calving interval (CI), and services per conception (SC) were the traits analyzed with uni and multitrait models using the software ASReml. The parity (P<0.01) and the contemporary groups (P<0.01) significantly affected the reproductive traits; however, the calf sex (P>0.05) was not. The heritability for the traits analyzed were low with values of 0.14±0.02, 0.15±0.02 and 0.04±0.01 for ICC, CI and SC, respectively. Genetic correlations were high between ICC and CI (0.99±0.43) but low between ICC and SC (0.10±0.14) and between CI and SC (0.09±0.11). Genetics parameters estimation models for the traits ICC, CI, and SC for Chacuba cows should consider parity and herd-year-quarter contemporary groups. Indirect selection for the calving interval using the interval calving-conception, can be implemented given the genetic correlation between these traits. [ABSTRACT FROM AUTHOR]