The northeast area of São Paulo state has been intensively deforested, resulting in a highly fragmented landscape composed of a few large patches and several small patches of natural vegetation ...surrounded by sugarcane, eucalyptus, and citrus plantations. In this scenario, we investigated the puma (Puma concolor) population size, sex ratio, and relatedness in two of the last, and largest, natural refuges in the area using a noninvasive method during 2004–2008. By collecting and individualizing fecal samples by microsatellites, we identified 17 individuals, 13 females (76.4%) and 4 males (23.6%) in these areas. Five females were sampled in distinct years and over an extended time and probably represented resident adults. By investigating the relatedness among individual pumas inhabiting the area, we found that only three animals were not related to each other. We also found evidence that young females might establish an adjacent or overlapping territory to their mothers (phylopatry). Moreover, we registered 11 road-killed individuals nearby the study area, ten males and one female, and six human–puma conflicts. The study area may act as a source of individuals that disperse across the matrix to occupy new home ranges, maintaining some degree of gene flow in a source–sink metapopulation structure. Finally, we recommend that puma management should be conducted at the landscape level to provide effective puma conservation in northeastern São Paulo state.
A new species of freshwater crab,
Fredius ibiapaba
, is described and illustrated from a mid-altitude forested patch in Ipú (Ibiapaba plateau, Ceará, northeastern Brazil), between 635 to 782 m. The ...new species can be separated from its congeners by the morphology of its first gonopod: proximal half remarkably swollen, sloping abruptly downwards distally to a nearly right-angular shoulder; mesial lobe much smaller than cephalic spine; cephalic lobe moderately developed; auxiliary lobe lip, delimiting field of apical spines, protruded all the way to distal margin of auxiliary lobe. Comparative 16S rDNA sequencing used to infer the phylogenetic placement of
Fredius ibiapaba
n. sp. revealed that it is the sister taxon of
F. reflexifrons
, a species which occurs allopatrically in the Amazon and Atlantic basin’s lowlands (<100 m).
Fredius ibiapaba
n. sp. and
F. reflexifrons
are highly dependent upon humidity and most probably were once part of an ancestral population living in a wide humid territory. Shrinking humid forests during several dry periods of the Tertiary and Quaternary likely have resulted in the fragmentation of the ancestral humid area and hence of the ancestral crab population.
Fredius reflexifrons
evolved and spread in a lowland, humid river basin (Amazon and Atlantic basins), whilst
F. ibiapaba
n. sp. evolved isolated on the top of a humid plateau. The two species are now separated by a vast intervening area occupied by the semiarid Caatinga
Background: Closed breeding populations are usefull to conduct basic and applied research. The Wye Angus herd is one of them. It was founded using only a few animals. The pedigree of the descendants ...of the original herd can be completely described by historical records resulting from strong selection. Wye Angus genetics has influenced that of Aberdeen Angus, Red Angus, and Brangus cattle worldwide. Objective: To evaluate parameters and genetic trends associated with the reproduction traits of the Wye Angus herd between the years 1937 and 2012. Methods: We used pedigree information of 11,692 individuals. The reproductive traits assessed were age at first calving (AFC), calving interval (CI), and scrotal circumference (SC). The covariance components were estimated by Bayesian inference. The genetic trends were obtained by linear regression of the genetic values over birth years of the animals. Results: The heritability estimates for AFC, and CI were negligible, although a small genetic gain was associated with CI. Because the AFC and CI values of the herd are small, past reproductive management has produced favourable results for the heifers. Conclusion: The Wye Angus herd has enough genetic variability for genetic gain through selection on SC.
Habitat fragmentation can promote patches of small and isolated populations, gene flow disruption between those populations, and reduction of local and total genetic variation. As a consequence, ...these small populations may go extinct in the long-term. The ocelot (Leopardus pardalis), originally distributed from Texas to southern Brazil and northern Argentina, has been impacted by habitat fragmentation throughout much of its range. To test whether habitat fragmentation has already induced genetic differentiation in an area where this process has been documented for a larger felid (jaguars), we analyzed molecular variation in ocelots inhabiting two Atlantic Forest fragments, Morro do Diabo (MD) and Iguaçu Region (IR). Analyses using nine microsatellites revealed mean observed and expected heterozygosity of 0.68 and 0.70, respectively. The MD sampled population showed evidence of a genetic bottleneck under two mutational models (TPM = 0.03711 and SMM = 0.04883). Estimates of genetic structure (FST = 0.027; best fit of k = 1 with STRUCTURE) revealed no meaningful differentiation between these populations. Thus, our results indicate that the ocelot populations sampled in these fragments are still not significantly different genetically, a pattern that strongly contrasts with that previously observed in jaguars for the same comparisons. This observation is likely due to a combination of two factors: (i) larger effective population size of ocelots (relative to jaguars) in each fragment, implying a slower effect of drift-induced differentiation; and (ii) potentially some remaining permeability of the anthropogenic matrix for ocelots, as opposed to the observed lack of permeability for jaguars. The persistence of ocelot gene flow between these areas must be prioritized in long-term conservation planning on behalf of these felids.
We assessed the polymorphism of 10 microsatellites in Brazilian Nellore cattle (Bos indicus) using a commercial multiplex system. Allele frequencies, polymorphism information content, heterozygosity ...and exclusion probability were calculated. Allele frequencies revealed that in the sample analyzed the markers were not equally polymorphic. The exclusion probabilities and the polymorphism information content of some loci in Nellore cattle were lower than in Bos taurus breeds. When all the microsatellites were considered the combined exclusion probability was 0.9989. This multiplex analysis can contribute toward pedigree information, adequate genetic improvements and breeding programs.
Canchim, a synthetic breed of cattle derived from the Charolais and Zebu group has been used in the beef-cattle industry in Brazil as an alternative for intensifying production. One of the main ...concerns with this breed is its poor fat deposition and consequently, there is an effort to increase the performance for this trait. The thyroglobulin gene is located in a QTL region for fat deposition, and reports describe the influence of a polymorphism in the 5´ leader sequence of that gene on marbling and subcutaneous fat thickness. This study analyzed the association of this polymorphism in the thyroglobulin gene, as well as of two flanking microsatellite markers, CSSM066 and ILSTS011, with backfat thickness in 987 Canchim beef cattle. The CSSM066 and ILSTS011 microsatellite markers have a effect on fat thickness in the studied populations. However, this trait did not have association with the polymorphism of the thyroglobulin gene, which suggests that other genes of bovine chromosome 14 may be responsible for the variation in this trait.
The genetics and ecology of pumas are well documented in North America but there is a lack of studies in South America, especially in Brazil. By means of a noninvasive method, faecal DNA analysis, we ...estimated puma abundance in two protected areas embedded in a human-disturbed landscape in the north-east of São Paulo state, in south-east Brazil. In 8 months of mark–recapture faeces sampling, 15 individual pumas were identified using seven microsatellite loci. The estimated abundance of pumas with the Jolly–Seber open population model was 23.81 ± SE 6.22. This is the first estimate of the abundance of pumas in a human-dominated landscape in São Paulo state, the most populous, developed and industrialized state of Brazil. The absence of high-quality habitats in the north-east of the state, the absence of direct competitors and the high availability of prey in protected areas are probably contributing to the high number of pumas concentrated in a relatively small area (c. 260 km2). Our results will contribute to the long-term monitoring of this puma population and, combined with other ecological, behavioural and genetic data, will help guide conservation action to maintain a viable population of the puma in this region.
Allozyme analyses have suggested that Neotropical orchid bee (Euglossini) pollinators are vulnerable because of putative high frequencies of diploid males, a result of loss of sex allele diversity in ...small hymenopteran populations with single locus complementary sex determination. Our analysis of 1010 males from 27 species of euglossine bees sampled across the Neotropics at 2-11 polymorphic microsatellite loci revealed only five diploid males at an overall frequency of 0.005 (95% CIs 0.002-0.010); errors through genetic nondetection of diploid males were likely small. In contrast to allozyme-based studies, we detected very weak or insignificant population genetic structure, even for a pair of populations > 500 km apart, possibly accounting for low diploid male frequencies. Technical flaws in previous allozyme-based analyses have probably led to considerable overestimation of diploid male production in orchid bees. Other factors may have a more immediate impact on population persistence than the genetic load imposed by diploid males on these important Neotropical pollinators.
Non-lethal sampling methods are of great interest for conservation genetic studies to prevent the death of individuals in populations that are threatened or in decline. With this aim, we tested a ...non-lethal method of partial antennae removal for DNA sampling in two euglossine bee species:
Euglossa cordata
and
Eulaema nigrita
. We validated the survival of the individuals through mark–recapture experiments during 16 months. The quality and quantity of the tissue for DNA analysis was verified through amplification and genotyping of nine and eleven microsatellite loci, respectively. Our results from the mark–recapture experiments showed equal recapture rates of individuals with intact and removed antennae (
E. cordata
χ
2
= 2.492, df = 1,
p
= 0.114;
E. nigrita
χ
2
= 1.683, df = 1,
p
= 0.194). Microsatellite loci were successfully genotyped in 97.1 and 97.6 % of the
E. cordata
and
E. nigrita
individuals, respectively. Our results validate the feasibility of using antennae tissue for DNA genetic analysis without compromising the survival of individual bees.
The main environmental factor that affects the regulation of reproductive seasonality is photoperiod through its effects on melatonin secretion. The melatonin receptor MTRN1A appears to be involved ...in regulating the reproductive seasonality and milk production in the period. The aim of this study was to identify polymorphisms in the MTRN1A gene and their possible associations with milk, fat and protein productions, fat and protein percentages, age at first calving, and first calving interval in buffaloes. Three genotypes (CC, CT, and TT) were identified by PCR-RFLP, and there was a significant association with protein percentage (P < 0.0001). Further studies are necessary to better understand the influence of melatonin gene and their receptors in the productive functions of buffaloes.
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