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1.
Alfonso L Zudaire G Sarries MV Viguera J Flamarique F 《Animal : an international journal of animal bioscience》2010,4(10):1739-1745
The study was carried out to provide information on uniformity of commercial pigs on some of the most important traits determining pork quality: carcass, loin, ham and shoulder weights, fatness, drip loss, pH and colour. Three batches of pigs raised at the same farm and slaughtered at four different dates in the same commercial abattoir were considered. Batches included halothane-free females and castrated males, Duroc and Pietrain sire lines and two slaughter weights, but a common maternal line. The first batch was obtained using commercial Duroc sire boars, and included a total of 112 animals (56 castrated males and 56 females). The second batch used Duroc and Pietrain sire boars with the target to achieve two different final weights (105 and 115 kg live weight); 128 animals were controlled (64 castrated males and 64 females), 16 for each combination of sire boar, sex and final weight. The last batch used only Pietrain sire boars with 96 controlled pigs (48 castrated males and 48 females). The uniformity was measured by the coefficient of variation (CV) and the coefficient of dispersion (CD) for all data available, and for groups of common sex, sire breed and slaughter weight. Differences in uniformity were tested among traits and groups by using confidence intervals (CIs) at 95% confidence level (CI95%) for the CV and CD. Results showed a significantly lower uniformity for drip loss (CV = 40.4%, CI95% 36.9% to 44.7%; CD = 32.1%, CI95% 28.7% to 35.4%) and backfat (CV = 22.8%, CI95% 21.1% to 24.8%; CD = 18.3%, CI95% 17.1% to 20.2%) the pH being the most uniform trait (CV = 3.2%, CI95% 3.0% to 3.5%; CD = 2.6%, CI95% 2.4% to 2.9%). When comparing different 'sire breed-sex-slaughter weight' groups, no consistent sex and slaughter weight differences in uniformity were found, but animals from Pietrain sire breed showed a tendency to be less uniform for carcass traits than animals from Duroc sire breed. Nevertheless, variability within those groups was very high and often similar to that observed when considering all the animals from all the groups. Small differences were found comparing uniformity when using the CV or the CD. CIs of these coefficients have proved to be a simple and useful tool for testing differences in uniformity. 相似文献
2.
C S Weil 《Mutation research》1978,50(2):285-291
A statistical reanalysis was performed on the data fecently reported on a 6-laboratory, collaborative cytogenetic study to measure and minimize interlaboratory variation. Three of the laboratories had mean values significantly different from the others on most of the 6 indexes of chemically-induced aberration; one laboratory with values higher and two with values lower. Furthermore, relative variability of the values around the means was consistently lower in one of the 6 participating laborabories. The results of the reanalysis of this collaborative study demonstrates that significant interlaboratory differences exist and that these should be adjusted or diminished before rat cytogenetic analysis can be an effective test system for evaluation of a compound for mutagenic potential. 相似文献
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Sofia Refetoff Zahed Aimee V. Kurian Charles T. Snowdon 《American journal of primatology》2010,72(4):296-306
Individual variation in infant caretaking behavior is prevalent among marmoset and tamarin monkeys. Although most group members participate in infant care, the timing and amount provided differs greatly. In this study, we quantified general trends in infant carrying behavior by using a longitudinal database that included 11 years of instantaneous scan observations following 80 births of cotton‐top tamarins. Using detailed focal observations on a subset of the same families (10 births) we identified influences that affected expression of infant care at the group and individual levels. Fathers were the primary carriers and paternal carry time gradually decreased with increasing infant age. Paternal carry time also decreased significantly with an increasing number of older sibling helpers. Most fathers began to carry on the first day postpartum. However, we report circumstances in which fathers delayed carrying until almost a month postpartum. Fathers retrieved infants the most, although adult brothers' rates of retrievals peaked and surpassed fathers' rates during week 4 postpartum. Fathers delayed rejection of infants until week 4, whereas mothers rejected infants immediately and throughout the eight weeks. Nonetheless, infants climbed onto their mothers more than onto any other family member. Mothers showed a high initial investment in carrying during the first two weeks, decreasing quickly thereafter. Maternal contributions to infant carrying remained low and relatively consistent regardless of group size. However, mothers dramatically increased their infant carrying behavior in families in which fathers were absent. Older siblings cared for infants more than did younger siblings, and brothers retrieved and carried infants more than did sisters. Individual expression of infant care changed to accommodate infant needs and changed according to varying social dynamics and circumstances across litters. Am. J. Primatol. 72:296–306, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
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Rebeca Haydenblit 《American journal of physical anthropology》1996,100(2):225-246
In this paper, the dental morphology of prehispanic Mesoamerican populations is described, compared, and examined within the context of New World dental variation. Twenty-eight morphological dental traits were studied and compared in four samples of prehispanic Mexican populations. After eliminating intra- and interobserver error, the dental morphological characteristics observed show evidence of heterogeneity among the populations. In particular, the oldest population, Tlatilco (1300–800 BC ), was significantly different from the other three groups, Cuicuilco (800–100 BC ), Monte Albán (500 BC –700 AD ) and Cholula (550–750 AD ). When the four samples were compared to other Mongoloid populations, either univariately or multivariately, it was observed that the Mexican groups did not follow a strict Sinodont (characteristic of Northeast Asia)/Sundadont (characteristic of Southeast Asia) classification (Turner [1979] Am. J. Phys. Anthropol. 51:619–636). From the traits examined, 27% presented frequencies consistent with Sinodont variation, while 73% of the traits showed similar incidence to Southeast Asian groups. Multivariately, the Mexican populations were found to fit an overall Sundadont classification. These results indicate that there is more dental morphological variation among American Indian populations than previously shown. © 1996 Wiley-Liss, Inc. 相似文献
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The Neolithic site of Çatalhöyük, Turkey (7400–5600 cal BC) is widely acknowledged for its role in the study of early farming communities. To better understand the social and community structure of this setting, an intracemetery biological distance analysis was conducted. Metric and nonmetric observations were recorded in both deciduous and permanent dentitions (n = 266) to explore phenotypic patterning of individuals interred within individual buildings. Specifically, this study tests the hypothesis that individuals within houses and house groupings represent family units and the social structure of Çatalhöyük was largely biological‐kin based. Multivariate and univariate statistical procedures were applied to phenotypic dental data. Results indicate that inclusion for interment within a house was only minimally related to biological affinity. Moreover, the site does not appear to be organized into larger, biologically related neighborhoods of houses. These findings suggest that Çatalhöyük may not have been a kin‐based society, largely because membership within a house cemetery was not solely defined on the basis of biological affinity, such as in a family group. Rather, it appears that social structure was centered on the house as the unifying social principle. The choice for interment location may have transcended biological lines thereby creating an alternate and more fluid definition of “kin.” These findings can be used to understand the transition to settled life and biological patterning in this Neolithic community. Am J Phys Anthropol 2011. © 2011 Wiley‐Liss, Inc. 相似文献
7.
J Letcher 《Journal of medical primatology》1992,21(1):24-29
Six years of necropsy records from a zoo colony of four tamarin species (Saguinus oedipus, S. geoffroyi, S. imperator, and S. mystax) were examined. Mean age at death was 4.0 years, average length in the colony at time of death was 3.4 years. Annual mortality rate varied between 9 and 30%. Gross necropsy findings, histopathologic, and bacteriological results indicate primary cause of death as follows: peritonitis (26%), septicemia (14%), nephritis (5%), hepatitis (5%), pneumonia (2%), and others. 相似文献
8.
Kathleen Fuller 《American journal of physical anthropology》1996,101(3):429-439
It has been argued (Grine, [1988] Evolutionary History of the “Robust” Australopithecines [New York. Aldine de Gruyter], pp. 223–243) that the australopithecine material from Swartkrans and Kromdraai represents distinct species. In an attempt to test the validity of separate taxa at Swartkrans and Kromdraai, Cope's (Cope [1989] Systematic Variation in Cercopithecus Dental Samples [Austin: University of Texas]) method of analysis was adapted and utilized. This procedure includes an analysis of the coefficients of variation (CVs) of the individual posterior teeth (buccal-lingual breadth) of a combined fossil sample compared with the CVs of several known single taxon reference groups. The Cope and Lacy (Cope and Lacy [1992] Am. J. Phys. Anthropol. 89:359–378) simulation technique was also employed in the analysis. Based on these analyses, there is no justification for a taxonomic separation between the australopithecine material from Swartkrans and Kromdraai. Therefore, the assertion that the Swartkrans and Kromdraai material represent two distinct species is not indicated by the available dental metric evidence. © 1996 Wiley-Liss, Inc. 相似文献
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A regional (North American) studbook of Saguinus geoffroyi, Geoffroy's tamarin, is presented. Supplemental information regarding range, habitat, status in the wild, taxonomy, husbandry, level of inbreeding, and international holdings is included. Living animals are cross-indexed by holding institution. 相似文献
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This study tests hypotheses regarding the ontogeny of canine tooth size dimorphism in five anthropoid primate species (Saguinus fuscicollis, Macaca mulatta, Cercocebus atys, Papio hamadryas, and Mandrillus sphinx). Canine measurements and chronological age data are analyzed to determine if bimaturism, a sex difference in the age at which eruption ceases, accounts for canine tooth sexual dimorphism. Canine height measurements are evaluated through a variety of regression techniques. Results show a lack of sexual dimorphism in Saguinus. While size dimorphism is absent in the deciduous teeth of all species analyzed, the adult teeth in cercopithecines become increasingly dimorphic through ontogeny. Female adult tooth eruption regularly precedes male tooth eruption, and regression-based eruption trajectories for both sexes intersect at about the age at which the female tooth reaches adult size. Males erupt the tooth later and more rapidly than females. Males also reach a larger adult size than females by erupting the tooth for much longer periods of time. Bimaturism is primary in the production of dimorphism, but rates of eruption show modest variation. These results point to the scheduling of sexual selection through intermale competition as a primary factor determining male eruption timing, rates of eruption, and adult size. Life history factors may play a role in determining the relations between the scheduling of intrasexual competition and canine eruption. Female contributions to sexual dimorphism are apparent in these species, suggesting that similar levels of dimorphism can be attained through diverse ontogenetic pathways. 相似文献
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Tokuma Yanai Haruaki Taniguchi Hiroki Sakai Kazunori Yoshida Naoto Kimura Akira Katou Yuji Oishi Toshiaki Masegi 《Journal of medical primatology》1996,25(4):309-312
Abstract: A rare case of bilateral adrenal myelolipomas in a female cotton-top tamarin is reported. Large bilateral masses in the adrenal glands were composed of mature adipose cells containing varying amounts of hematopoietic cells of the myeloid, erythroid, and megakaryocyte series. The gross and histologic features of this case closely resemble human “giant” adrenal myelolipomas. 相似文献
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通过变异系数和性状差异显著性检验,研究了海南粗榧在坝王岭等5个种群内和种群间不同形态变异以及形态总体变异。结果表明:①海南粗榧营养器官性状比生殖器官性状变异大;枝性状组中,分枝角度变异较小;叶性状组中,叶数量变异较大;球果、种子生物量变异都大于它们的其它性状。②在5个种群内,同一性状变异幅度基本相同。③同一性状在种群间和种群内的变异基本接近。④不同性状在种群间存在差异,有的显著,有的不显著,但种群间形态总体差异都不显著 相似文献
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研究寡核苷酸芯片的重复性与间隔臂(spacer)和探针长度之间的相关性。设计12条不同长度的带有不同spacer的探针,与749bp荧光标记靶序列杂交。扫描分析三次杂交结果,用Quantrray定量分析软件进行分析,随探针长度的延长,杂交信号的变异系数逐步降低,15mer的探针杂交的信号较弱,杂交不够稳定,重复性也相对较差,20mer、25mer、30mer的探针的变异系数逐渐降低。spacer为15时变异系数最小。说明选择spacer为poly(dT)15的25mer和30mer的探针可以获得较好的重复性。 相似文献
15.
Asier R. Larrinaga Pablo Guitián 《Biological journal of the Linnean Society. Linnean Society of London》2016,118(4):940-950
Plant trait variation can be the result of environmental variability, developmental instability, and plasticity, although it can also arise from previous selective pressures on fruit traits themselves or directly on their variation. We aimed to quantify fruit size and shape variability at within‐plant, among‐plant, among‐population, and among‐year levels. For 2 years, we measured fruit size and shape along the geographical range of Corema album, aiming to determine whether (1) the population level among‐plant variation is lower than within‐plant and among‐population variation and (2) the ratio of within‐plant to among‐plant variation follows a latitudinal pattern. Levels of fruit variation were in accordance with the reported mean levels for reproductive organs. Most variance concentrated on within‐ and among‐individual levels for size, showing higher values for among‐individual variation in fruit shape. Although fruit size retained important variation among populations, this source of variance was negligible for fruit shape. This difference could arise from contrasting mechanical or developmental constraints. Despite the marked climatic differences along the latitudinal range of the species, latitude did not affect the ratio of within‐ to among‐plant variation. We show that an analysis of the often‐disregarded sources of intraspecific variation can produce unexpected results that deserve further investigation. 相似文献
16.
Fifteen paired fossil populations of Microtus arvalis and Microtus agrestis from southwestern Europe have been analysed from a morphological and morphometric point of view. The sites under consideration are located in the northern Iberian Peninsula and southern France, from the Middle Pleistocene to the end of the Late Pleistocene. The aim of this study is to stress once again the importance of keeping these two species separated in the fossil record in order to recognize specific trends of evolution and divergence and to obtain more precise information on palaeoclimatic and palaeoenvironmental conditions. It was possible to observe remarkable intraspecific differences between Middle and Late Pleistocene populations of both species. Furthermore, in synchronic co-specific populations from the Late Pleistocene, climatic and geographic conditions seem to exert a major influence in shaping intraspecific changes in dental pattern. 相似文献
17.
Paul A. Garber 《American journal of primatology》1989,19(4):203-216
From field data collected in the Amazon Basin of northeastern Peru, I present evidence that moustached (Saguinus mystax) and saddle-back (Saguinus fuscicollis) tamarins maintain detailed knowledge of the distribution and location of many tree species in their home range. During the wet season months of October through December 1984, fruits and exudates from 20 tree species and over 150 individual trees accounted for 75% of plant feeding time. These trees exhibited a patchy distribution; mean nearest-neighbor distances between trees of the same species averaged 148 meters. Moustached and saddle-back tamarins visited an average of 13 trees per day, concentrating their feeding efforts on 4–11 individual trees from a small number of target species. In 70% of all cases the nearest tree of a given species was selected as the next feeding site. Movement between these sites was characterized by relatively straight-line travel. It is argued that S. mystax and S. fuscicollis offset the patchiness component of the fruit and exudate part of their diet through goal-directed foraging and an ability to compare accurately the distances and directions from their present location to a large number of potential feeding trees. 相似文献
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Valerie Sgheiza; 《American journal of physical anthropology》2024,184(1):e24908
Most research in human dental age estimation has focused on point estimates of age, and most research on dental development theories has focused on morphology or eruption. Correlations between developing teeth using ordinal staging have received less attention. The effect of demographic variables on these correlations is unknown. I tested the effect of reference sample demographic variables on the residual correlation matrix using the lens of cooperative genetic interaction (CGI). 相似文献