Genetic associations between accumulated productivity, and reproductive and growth traits in Nelore cattle

The total meat yield in a beef cattle production cycle is economically very important and depends on the number of calves born per year or birth season, being directly related to reproductive potential. Accumulated Productivity (ACP) is an index that expresses a cow's capacity to give birth regularly at a young age and to wean animals of greater body weight. Using data from cattle participating in the "Program for Genetic Improvement of the Nelore Breed" (PMGRN - Nelore Brasil), bi-trait analyses were performed using the Restricted Maximum Likelihood method based on an ACP animal model and the following traits: age at first calving (AFC), female body weight adjusted for 365 (BW365) and 450 (BW450) days of age, and male scrotal circumference adjusted for 365 (SC365), 450 (SC450), 550 (SC550) and 730 (SC730) days of age. Median estimated ACP heritability was 0.19 and the genetic correlations with AFC, BW365, BW450, SC365, SC450, SC550 and SC730 were 0.33, 0.70, 0.65, 0.08, 0.07, 0.12 and 0.16, respectively. ACP increased and AFC decreased over time, revealing that the selection criteria genetically improved these traits. Selection based on ACP appears to favor the heaviest females at 365 and 450 days of age who showed better reproductive performance as regards AFC. Scrotal circumference was not genetically associated with ACP. (C) 2007 Elsevier B.V. All rights reserved.

PHOSPHORUS EFFECTS IN THE NUTRITION and GROWTH of DEVELOPING MANGO PLANTS

The objective was to study the effects of phosphorous (P) fertilization on nutritional and developmental aspects of growing mango plants. The mango plants were evaluated by soil chemical analyses, leaf chemical analyses, biological examination of plant growth, and the starting point of fruit production. Having this in view, an experiment was set up on 2 January 2003, at Flora, a farm in Uberlandia, state of Minas Gerais, Brazil. The soil was a clayish Oxisol. The doses at planting were: D0 = zero, D1 = 40, D2 = 100, D3 = 200, and D4 = 300 g of P2O5 plant-1. These doses at the beginning of the second year were multiplied by 1.5 and at the beginning of the third year by 2.0 and applied to the plants. The fertilizer used in this experiment was triple superphosphate (44% of P2O5.). During August of 2004, 2005, and 2006, soil samples were taken at a depth of 20 cm in between the plant rows. Leaf samples were taken during August of 2004 and 2005 to determine macro- and micronutrient contents in the leaves. Plant stem diameter was measured during January of 2004 and 2005. Plant height and crown radius were measured during January of 2005 and fruit production in 2005 and 2006. Fertilizer applications increased the level of P in the soil but significantly influenced plant performance only after the second year. The effects of phosphorus on mango plants take place slowly leading to increments in plant stem diameter only at the third year. Fruit set was not influenced by phosphorous fertilization.

Genetic associations between carcass traits measured by real-time ultrasound and scrotal circumference and growth traits in Nelore cattle

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Genetic associations between flight speed and growth traits in Nellore cattle

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

First polymorphisms in JY-1 gene in cattle (Bos taurus indicus) and their association with sexual precocity and growth traits

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

Genetic associations between stayability and reproductive and growth traits in Canchim beef cattle

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Macromineral requirements for the maintenance and growth of Boer crossbred kids

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

Genetic correlations between heifer subsequent rebreeding and age at first calving and growth traits in Nellore cattle by Bayesian inference

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

Glucose consume and growth of E. coli under electromagnetic field

E. coli,em caldo glicosado,foi submetida a campo eletromagnético de intensidade 5G, gerado por fonte de tensão alternada de 60 Hz . Os crescimento e consumo de glicose foram avaliados através do teste não-paramétrico de Mann-Whitney para comparação de dois grupos. Após 8 h de exposição encontraram-se menor valor da glicose residual e maior turbidez nos tubos expostos ao campo evidenciando efeito positivo deste. A causa deste efeito no consumo da glicose pode ser pela estimulação de sistema de transporte de glicose, como a Difusão Facilitada ou por um tipo de fenômeno chamado ressonância ciclotrônica. O aumento do crescimento pode ser pelo encurtamento da lag phase e estimulação da log phase.

Evasive Maneuvers in Space Debris Environment and Technological Parameters

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Lung morphology and growth of rats exposed to tobacco smoke and alcohol

OBJETIVO: Investigar os efeitos morfológicos da exposição crônica à inalação de fumaça do tabaco e o do consumo de álcool nos pulmões e no crescimento de ratos. MÉTODOS: Sessenta ratos Wistar machos foram distribuídos em quatro grupos: controle, tabaco, álcool e tabaco + álcool, e acompanhados por um período de 260 dias. No final do periodo foi realizada análise morfológica dos pulmões por microscopia óptica e eletrônica. O crescimento dos ratos foi investigado através da medição do comprimento focinho-ânus, peso corporal e índice de massa corporal. RESULTADOS: Os três grupos expostos às drogas apresentaram peso e comprimento significativamente menores que os do grupo controle. As percentagens de bronquiolite e alveolite, e o diâmetro alveolar médio foram maiores nos grupos expostos à fumaça do tabaco, mas sem significancia estatística quando comparadas ao grupo controle. A microscopia eletrônica revelou apoptose mais intensa e lesões degenerativas no grupo de fumantes, enquanto lesões degenerativas nos corpos lamelares foram mais intensas com a associação de ambas as drogas. CONCLUSÕES: Este modelo experimental mostrou alterações morfológicas observadas por microscopia eletrônica, principalmente devido à exposição ao tabaco. Tanto o alcool como o tabaco prejudicaram o crescimento dos animais, o tabaco mostrando um efeito maior sobre o comprimento e o álcool sobre o peso corporal.

Association between IGF-I, IGF-IR and GHRH gene polymorphisms and growth and carcass traits in beef cattle

Molecular biology techniques are of help in genetic improvement since they permit the identification, mapping and analysis of polymorphisms of genes encoding proteins that act on metabolic pathways involved in economically interesting traits. The somatotrophic axis, which essentially consists of growth hormone releasing hormone (GHRH), growth hormone (GH), insulin-like growth factors I and II (IGF-I and IGF-II), and their associated binding proteins and receptors (GHRHR, GHR, IGF-IR and IGF-IIR), plays a key role in the metabolism and physiology of mammalian growth. The objectives of the present study were to estimate the allele and genotype frequencies of the IGF-I/SnaBI, IGF-IR/TaqI and GHRH/HaeIII gene polymorphisms in different genetic groups of beef cattle and to determine associations between these polymorphisms and growth and carcass traits. For this purpose, genotyping was performed on 79 Nellore animals, 30 Canchim (5/8 Charolais+3/8 Zebu) animals and 275 crossbred cattle originating from the crosses of Simmental (n=30) and Angus (n=245) sires with Nellore females. In the association studies, traits of interest were analyzed using the GLM procedure of SAS and least square means of the genotypes were compared by the Tukey test. Associations of IGF-I/SnaBI genotypes with body weight and subcutaneous backfat were significant (p < 0.05), and nearly significant for longissimus dorsi area (p=0.06), with the 1313 genotype being favorable compared to the AB genotype. No significant associations were observed between this polymorphism and weight gain or carcass yield (P > 0.05). The IGF-IR/TaqI and GHRH/HaeIII polymorphisms showed no association with production traits. (c) 2004 Elsevier B.V All rights reserved.

Haematological response and growth performance of Nile tilapia (Oreochromis niloticus L.) fed diets containing folic acid

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

Effects of incubation temperature on muscle morphology and growth in the pacu (Piaractus mesopotamicus)

This study describes the influence of incubation temperature during initial development phase on the morphology and muscle growth characteristics in the pacu (Piaractus mesopotamicus). Pacu eggs were incubated at 25, 27, and 29 degreesC until hatching. After day 5, fish from each temperature were transferred to 5001 tanks. At hatching and after 5, 25, and 60 days, muscle samples were collected, some were frozen in liquid nitrogen and others fixed in 4% paraformaldehyde or 2.5% glutaraldehyde. These samples were used for morphological, histochemical, immunohistochemical, and morphometric analysis. At hatching, we observed a superficial monolayer of small diameter fibers, lying just beneath the skin surrounding several round cells. From day 5, we observed two distinct populations of muscle fibers distributed in two layers: (1) red-in a superficial region with aerobic activity, and following acid preincubation, high mATPase activity, and 2) white-with anaerobic activity, and following alkaline preincubation, high mATPase activity. Twenty-five days after hatching, an intermediate layer and cell proliferating zones could be seen in the dorsal fin muscle region, with intermediate characteristics. Throughout the experimental period, there was an increase in muscle mass due to new fiber recruitment in the cell proliferating zones and between the more differentiated fibers in red, intermediate, and white muscles. This was more obvious from day 25, and at 29 degreesC than at 25 and 27 degreesC. Fiber hypertrophy occurred from hatching to 60 days and was more evident from 5 to 25 days. The number of proliferating nuclei (PCNA-labelling) increased from hatching to 60 days, and was more obvious in the 29 degreesC group at 60 days. Our results show that at incubation temperatures of 25, 27 and 29 degreesC, hypertrophy was predominantly from hatching to 25 days, after that muscle growth by hyperplastic mechanism increased. The interaction of muscle hypertrophic and hyperplastic growth processes in the 29 degreesC group produced the largest fish at the end of the experiment. (C) 2004 Elsevier B.V. All rights reserved.