Quantitative trait loci (QTL) mapping for growth traits on bovine chromosome 14

Quantitative trait loci (QTL) mapping in livestock allows the identification of genes that determine the genetic variation affecting traits of economic interest. We analyzed the birth weight and weight at 60 days QTL segregating on bovine chromosome BTA14 in a F2 resource population using genotypes produced from seven microsatellite markers. Phenotypes were derived from 346 F2 progeny produced from crossing Bos indicus Gyr x Holstein Bos taurus F1 parents. Interval analysis to detect QTL for birth weight revealed the presence of a QTL (p < 0.05) at 1 centimorgan (cM) from the centromere with an additive effect of 1.210 ± 0.438 kg. Interval analysis for weight at 60 days revealed the presence of a QTL (p < 0.05) at 0 cM from the centromere with an additive effect of 2.122 ± 0.735 kg. The region to which the QTL were assigned is described in the literature as responsible for some growth traits, milk yield, milk composition, fat deposition and has also been related to reproductive traits such as daughter pregnancy rate and ovulation rate. The effects of the QTL described on other traits were not investigated.

Association of the bovine major histocompatibility complex (BoLA) BoLA-DRB3 gene with fat and protein production and somatic cell score in Brazilian Gyr dairy cattle (Bos indicus)

The effect of the bovine major histocompatibility complex (BoLA) locus on animal health may be due to a direct action of its alleles on immune functions, whereas its indirect effect on production traits might be explained by the better general health conditions of more productive animals. In the present study, the BoLA-DRB3 gene was investigated in 1058 cows belonging to seven Brazilian Gyr Dairy herds (Bos indicus, Zebu cattle). A total of 37 alleles were identified, 15 of them described for the first time in a Zebu breed. A highly significant association (p < 0.02) was observed between allele *54 and a decrease (-26.1 kg) in milk protein yield and there was a significant association (p < 0.05) between this allele and lower (-26.07 kg) milk fat yield. There was also a significant association (p < 0.05) between allele *6 and decreased (-12.47 kg) milk protein and allele *7 and increased (12.72 kg) milk protein. There were also indications of association (p < 0.10) between somatic cell score (SCS) and alleles *3 (SCS increased by 0.54 units) and *31 (SCS increased by 0.46 units). The highly significant association of allele *54 with lower protein yield suggests the possible use of this allele in marker-assisted selection programs.

Quantitative trait locus affecting birth weight on bovine chromosome 5 in a F2 Gyr x Holstein population

Segregation between a genetic marker and a locus influencing a quantitative trait in a well delineated population is the basis for success in mapping quantitative trait loci (QTL). To detect bovine chromosome 5 (BTA5) birth weight QTL we genotyped 294 F2 Gyr (Bos indicus) x Holstein (Bos taurus) crossbreed cattle for five microsatellite markers. A linkage map was constructed for the markers and an interval analysis for the presence of QTL was performed. The linkage map indicated differences in the order of two markers relative to the reference map (http://www.marc.usda.gov). Interval analysis detected a QTL controlling birth weight (p < 0.01) at 69 centimorgans (cM) from the most centromeric marker with an effect of 0.32 phenotypic standard-error. These results support other studies with crossbred Bos taurus x Bos indicus populations

A assistência preventiva do enfermeiro ao trabalhador de enfermagem / Nurse's preventive attendance to the nursing worker

A temática do presente estudo surgiu da experiência que temos em nossa prática profissional, onde pudemos observar o absenteísmo dos profissionais de enfermagem decorrentes de doenças relacionadas ao trabalho, o que nos despertou o interesse em nos aprofundar no papel do enfermeiro nas ações preventivas relacionadas à saúde do trabalhador de enfermagem em sua trajetória profissional comparando-as com as Normas Regulamentadoras. As ações preventivas em saúde do trabalhador é uma busca constante, que necessita de mais investimento com o objetivo de melhorar as condições de trabalho, proporcionando um ambiente saudável.

Criopreservaçäo de embriöes de camundongos em diferentes estágios de desenvolvimento utilizando metanol como crioprotetor / Criopreservation of mouse embryos in different stages of development using methanol as a cryoprotectant

O presente trabalho foi planejado para testar os diferentes estágios de desenvolvimento encontrados no quarto dia após injeçäo de HCG em camundongos superovulados, afetam as taxas de desenvolvimento dos embriöes, criopreservados em uma soluçäo 3M de metanol.Foram criopreservados embriöes nos estágios de: 1) mórula, 2) blastocisto jovem (aqueles em que a cavidade ocupasse menos do que 50% do volume do embriäo), e 3) blastocisto (aqueles em que a cavidade ocupasse mais do que 50% do volume do embriäo). Os embriöes foram colocados diretamente numa soluçäo 3M de metanol em PBSS, a temperatura ambiente, durante 10 minutos, acondicionados em "paillets" de 0,25 ml, e colocados no aparelho de criopreservaçäo, diretamente, a 10§C. Após 5 minutos a essa temperatura, foi induzida a formaçäo de gelo. Uma vez transcorridos 6 minutos de equilíbrio, após a nucleaçäo a 10§C, os embriöes foram submetidos a queda de temperatura de 0,5§C, por minutos, até atingir a temperatura de 30§C, quando foram mergulhados diretamente em nitrogênio líquido a 196§. Näo houve diferença estatisticamente significativa, na percentagem de desenvolvimento, em cultura, entre os embriöes criopreservados nos estágios de mórula e blastocisto jovem (p> 0,05) mas houve uma diferença significativa (p<0,05) dos embriöes criopreservados, no estágio de blastocisto, quando comparado com o estágio de mórula e blastocisto jovem.