A new species of Ceratolacis (Podostemaceae) from Minas Gerais, Brazil

Volume: 14Start Page: 108End Page: 11

Assessment of runs of homozygosity islands and estimates of genomic inbreeding in Gyr (Bos indicus) dairy cattle.

Abstract BACKGROUND: Runs of homozygosity (ROH) are continuous homozygous segments of the DNA sequence. They have been applied to quantify individual autozygosity and used as a potential inbreeding measure in livestock species. The aim of the present study was (i) to investigate genome-wide autozygosity to identify and characterize ROH patterns in Gyr dairy cattle genome; (ii) identify ROH islands for gene content and enrichment in segments shared by more than 50% of the samples, and (iii) compare estimates of molecular inbreeding calculated from ROH (FROH), genomic relationship matrix approach (FGRM) and based on the observed versus expected number of homozygous genotypes (FHOM), and from pedigree-based coefficient (FPED). RESULTS: ROH were identified in all animals, with an average number of 55.12 ± 10.37 segments and a mean length of 3.17 Mb. Short segments (ROH1-2 Mb) were abundant through the genomes, which accounted for 60% of all segments identified, even though the proportion of the genome covered by them was relatively small. The findings obtained in this study suggest that on average 7.01% (175.28 Mb) of the genome of this population is autozygous. Overlapping ROH were evident across the genomes and 14 regions were identified with ROH frequencies exceeding 50% of the whole population. Genes associated with lactation (TRAPPC9), milk yield and composition (IRS2 and ANG), and heat adaptation (HSF1, HSPB1, and HSPE1), were identified. Inbreeding coefficients were estimated through the application of FROH, FGRM, FHOM, and FPED approaches. FPED estimates ranged from 0.00 to 0.327 and FROH from 0.001 to 0.201. Low to moderate correlations were observed between FPED-FROH and FGRM-FROH, with values ranging from -0.11 to 0.51. Low to high correlations were observed between FROH-FHOM and moderate between FPED-FHOM and FGRM-FHOM. Correlations between FROH from different lengths and FPED gradually increased with ROH length. CONCLUSIONS: Genes inside ROH islands suggest a strong selection for dairy traits and enrichment for Gyr cattle environmental adaptation. Furthermore, low FPED-FROH correlations for small segments indicate that FPED estimates are not the most suitable method to capture ancient inbreeding. The existence of a moderate correlation between larger ROH indicates that FROH can be used as an alternative to inbreeding estimates in the absence of pedigree records

Macrófitas aquáticas da lagoa de Jijoca de Jericoacoara, Ceará, Brasil Aquatic macrophytes of Jijoca of Jericoacoara lagoon, Ceará, Brazil

A lagoa de Jijoca de Jericoacoara situa-se no litoral do Ceará, Nordeste do Brasil (2º50'10'' e 2º55'32''S - 40º28'32'' e 40º24'09''W), sendo bordejada em sua extremidade Norte por dunas e por vegetação de tabuleiro nas demais faces. Realizou-se o levantamento da composição florística e da estrutura da comunidade de macrófitas aquáticas presentes na lagoa. As amostras das plantas foram coletadas e depositadas no herbário EAC. Densidade, freqüência e cobertura das espécies foram amostradas em 10 transectos plotados em áreas com boas condições de conservação de suas margens, evitando-se áreas urbanas e de atividade agropecuária adjuntas à lagoa. Apresenta-se a lista de 45 espécies ocorrentes, suas formas biológicas e dados da estrutura da comunidade. As espécies com maior índice do valor de importância (IVI) foram Eleocharis mutata (L.) Roem. & Schult., Paspalidium geminatum Stapf, Eleocharis atropurpurea (Retz.) Kunth, Nymphoides indica (L.) Kuntze e Echinodorus tenellus (Mart.) Buchen. A forma de vida predominante foi "plantas enraizadas ao substrato - anfíbias tolerantes à seca". Em relação à profundidade, ocorre aumento da diversidade de espécies de áreas mais profundas para 0-0,5m de espessura da lâmina d'água.<br>The Jijoca of Jericoacoara lake is located at Ceará Coastal Zone, Northeast of Brazil (2º50'10'' e 2º55'32''S - 40º28'32'' e 40º24'09''W), and it has sand dunes on the Northern shore and arboreal semi-deciduous vegetation around the other lakesides. A floristic and communities structure survey of aquatic flora was conducted. Plant samples were collected and included in the EAC Herbarium. The density, frequency, and cover were measurements used in describing communities by intercept transect sampling. Sampling was carried out in Jijoca of Jericoacoara lake at 10 localities, except areas with human impact, such as urban and agricultural areas. A list of 45 species, their life forms and vegetation structure are presented. The higher importance value index (IVI) species were Eleocharis mutata (L.) Roem. & Schult., Paspalidium geminatum Stapf, Eleocharis atropurpurea (Retz.) Kunth, Nymphoides indica (L.) Kuntze, and Echinodorus tenellus (Mart.) Buchen. The most common life-form was "emergent bottom-rooted plants with amphibious habit". In relation to depth, species diversity increased from the deeper areas and peaked at 0-0,5 m above water level