Genetic parameter estimates and principal component analysis of breeding values of reproduction and growth traits in female Canchim cattle

Phenotypic data from female Canchim beef cattle were used to obtain estimates of genetic parameters for reproduction and growth traits using a linear animal mixed model. In addition, relationships among animal estimated breeding values (EBVs) for these traits were explored using principal component analysis. The traits studied in female Canchim cattle were age at first calving (AFC), age at second calving (ASC), calving interval (CI), and bodyweight at 420 days of age (BW420). The heritability estimates for AFC, ASC, CI and BW420 were 0.03±0.01, 0.07±0.01, 0.06±0.02, and 0.24±0.02, respectively. The genetic correlations for AFC with ASC, AFC with CI, AFC with BW420, ASC with CI, ASC with BW420, and CI with BW420 were 0.87±0.07, 0.23±0.02, -0.15±0.01, 0.67±0.13, -0.07±0.13, and 0.02±0.14, respectively. Standardised EBVs for AFC, ASC and CI exhibited a high association with the first principal component, whereas the standardised EBV for BW420 was closely associated with the second principal component. The heritability estimates for AFC, ASC and CI suggest that these traits would respond slowly to selection. However, selection response could be enhanced by constructing selection indices based on the principal components. © CSIRO 2013.

Length-weight relationship and reproduction of the guppy Poecilia reticulata (Cyprinodontiformes: Poeciliidae) in urban drainage channels in the Brazilian city of Belém

O presente trabalho tem por objetivo descrever aspectos populacionais relacionados ao estabelecimento da relação peso/comprimento, estimativa de tamanho de primeira maturação (L) e período reprodutivo de Poecilia reticulata encontrados em sistemas de coleta residual no campus da Universidade Federal do Pará, região metropolitana de Belém – PA (Brasil). Foram realizadas coletas mensais no período de junho de 2006 a março de 2007, utilizando um puçá, que resultou na captura de 1.936 exemplares, sendo 942 machos e 994 fêmeas. As fêmeas apresentaram-se maiores e mais pesadas que os machos. A relação peso/comprimento para machos foi estabelecida pela equação Pt = 5 × 10^-5× Ct^2,397 e para fêmeas esta foi dada pela fórmula Pt = 3 × 10^-6 × Ct3,419. Os valores estimados para L foi 17,5 mm para machos 20,4 mm para fêmeas, sugerindo que os machos iniciam atividades reprodutivas em tamanhos menores que as fêmeas. A frequência mensal de fêmeas maduras não variou significativamente. Além disso, também não foram encontradas diferenças na proporção sexual durante os períodos investigados, sendo no geral, a proporção de fêmeas iguais as de machos. Desta forma, verificamos que, apesar das condições presentes nos sistemas de coleta residual da UFPA, a espécie P. reticulata parece ter adaptado seus processos biológicos.

Geographical variation in the reproduction and sexual dimorphism of the Boddaert's tropical racer, Mastigodryas boddaerti (Serpentes: Colubridae)

We obtained data on time of sexual maturity, dimorphism, fecundity and on the reproductive cycle of Mastigodryas boddaerti (Sentzen, 1796) through the examination of 321 preserved specimens, of which 221 were collected in the Brazilian Amazon region and 100 in the Cerrado savannas of Central Brazil. The degree of sexual size dimorphism (snout-vent length, SVL) was significantly greater in the specimens from the Cerrado in comparison with those from the Amazon. Females had a significantly larger number of ventral scales, on average, whereas males had more sub-caudal scales. However, there was no intersexual difference in tail length or head width, although the heads of the males were significantly longer, which may reflect dietary differences. Breeding females from the Amazon region contained between one and six eggs (N = 12, mean = 3.0), whereas two females from the Cerrado had four to six eggs (N = 10, mean = 5.0). No relationship was found between the SVL of the Amazonian females and the number of eggs or vitellogenic follicles they contained (Cerrado females were not analyzed here due to small sample size). Males are smaller than their female counterpart when they reach sexual maturity. Even though females from the Amazon reproduce throughout the year, females from the Cerrado breed seasonality.

Reproduction of Meloidogyne enterolobii in rootstocks and cucumber hybrids

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Genomic selection and assisted reproduction technologies to foster cattle breeding

Genomics has been propagated as a paradigm shifting innovation in livestock during the last decade. The possibility of predicting breeding values using genomic information has revolutionized the dairy cattle industry and is now being implemented in beef cattle. In this paper we discuss how genomics is changing cattle breeding through genomic selection, and how this change is creating new ways to articulate assisted reproduction technologies with animal breeding. We also debate that the scientific community is still starting the long journey to reveal the functional aspects of the cattle genome, and that knowledge in this field is the frontier to a whole new venue for the development of novel applications in the livestock sector.

Effect of honey feeding by thyrinteina arnobia males and females on their reproduction and longevity

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Characterisation of the methylation pattern in the intragenic CpG island of the IGF2 gene in Bos taurus indicus cumulus cells during in vitro maturation

The aim of this study was to characterise the methylation pattern in a CpG island of the IGF2 gene in cumulus cells from 1-3 mm and a parts per thousand yenaEuro parts per thousand 8.0 mm follicles and to evaluate the effects of in vitro maturation on this pattern.Genomic DNA was treatment with sodium bisulphite. Nested PCR using bisulphite-treated DNA was performed, and DNA methylation patterns have been characterised.There were no differences in the methylation pattern among groups (P > 0.05). Cells of pre-IVM and post-IVM from small follicles showed methylation levels of 78.17 +/- 14.11 % and 82.93 +/- 5.86 %, respectively, and those from large follicles showed methylation levels of 81.81 +/- 10.40 % and 79.64 +/- 13.04 %, respectively. Evaluating only the effect of in vitro maturation, cells of pre-IVM and post-IVM COCs showed methylation levels of 80.17 +/- 12.01 % and 81.19 +/- 10.15 %.In conclusion, the methylation levels of the cumulus cells of all groups were higher than that expected from the imprinted pattern of somatic cells. As the cumulus cells from the pre-IVM follicles were not subjected to any in vitro manipulation, the hypermethylated pattern that was observed may be the actual physiological methylation pattern for this particular locus in these cells. Due the importance of DNA methylation in oogenesis, and to be a non-invasive method for determining oocyte quality, the identification of new epigenetic markers in cumulus cells has great potential to be used to support reproductive biotechniques in humans and other mammals.

Impact of adrenalectomy and dexamethasone treatment on testicular morphology and sperm parameters in rats: insights into the adrenal control of male reproduction

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Reproduction, food dynamics and exploitation level of Oreochromis niloticus (Perciformes: Cichlidae) from artisanal fisheries in Barra Bonita Reservoir, Brazil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Dinâmica folicular ovariana e bases para a aplicação das biotécnicas da reprodução em bovinos

In the last years Brazil has achieved a leading position in worldwide cattle breeding. This country is consolidating the practice of an intensive and technical level cattle breeding, due to greater emphasis on reproductive efficiency and genetic improvement. The attention given to reproductive efficiency became to enhance the genetic improvement process, by exploiting the full reproductive potential of the animals. The biotechniques applied to reproduction arised to expand the reproductive potential for greater economic return. Are the most important reproductive biotechniques the FTAI and in vivo and in vitro embryo production for embryo transfer. Different hormonal treatments are consolidating to interfere with normal physiology in order to achieve the desired goals. The FTAI works to increase the reproductive rates of cattle through pre-booked artificial insemination in all the females in reproduction, without the need for estrous detection. The in vivo and in vitro embryo production aims to distribute the genetics of males and females genetically improved by transferring their embryos to genetically inferior females. Superovulation treatments designed to prevent the mechanism of dominance, which results in many follicles ovulating simultaneously for in vivo embryo production. To the in vitro embryo production, the technique of ovarian puncture guided by transvaginal ultrasound allows to aspirate a number of quality oocytes. The application of biotech is based on knowledge of the female and ovarian reproductive physiology and knowledge of their acting in different breeds and environments.

Impact of the medicine Hydroxyurea on reproduction and development, using Drosophila melanogaster as a model organism

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Genome-wide association study of reproduction traits in Nelore cattle, including additional phenotypic information from non-genotyped animals

Pós-graduação em Genética e Melhoramento Animal - FCAV

Carrying progeny on the back: reproduction in the Brazilian aquatic frog Pipa carvalhoi

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)