Finishing precocity visual score and genetic associations with growth traits in Angus beef cattle.

Finishing precocity visual score selection was adopted to estimate the time from birth to reach slaughter age. This study estimated (co)variance components and genetic correlations for the finishing precocity score at weaning (WP) and yearling (YP) stages by using daily weight gain (BWG = from birth to weaning; WYG = from weaning to yearling) and speed of weight gain (BWR = from birth to weaning; WYR = from weaning to yearling) as support for a genetic evaluation program for Angus beef cattle. Genetic parameters were estimated using Bayesian inference, considering multi-trait analysis and assuming a nonlinear model for WP and YP and linear model for all other traits. Direct heritability estimates were 0.17 (WP), 0.19 (YP), 0.15 (BWG), 0.16 (WYG), 0.15 (BWR), and 0.16 (WYR). The genetic correlation between the finishing precocity score at two ages (weaning and yearling) was 0.61. Positive and moderate genetic correlations were obtained between WP and BWG (0.47) and WP and BWR (0.46). In contrast, negative and low genetic associations were estimated between WP and yearling growth traits (-0.16, WYG; -0.15, WYR). Genetic correlations between YP and other traits were positive 0.29 (BWG), 0.28 (BWR), 0.48 (WYG), and 0.47 (WYR). The selection response for the finishing precocity score at weaning and yearling ages would be low. Selection to increase WP and YP should result in favorable genetic changes in daily weight gains as a correlated response. Therefore, to obtain animals suited for beef cattle production systems, finishing precocity score and growth traits should be considered as selection criteria.

Origins and genetic diversity of British cattle breeds in Brazil assessed by pedigree analyses.

Pedigree information available for Angus (ANG), Devon (DEV), Hereford (HER), and Shorthorn (SHO) cattle in Brazil was analyzed to appraise the genetic diversity and population structure of these breeds. Pedigree records collected from the beginning of the 20th century until 2010 were used in the analyses. Over time, the number of herdbook registrations declined in HER after a peak in the 1970s, remained low in DEV and SHO, and increased steadily in ANG since the 1990s, such that it the latter is now the leading British cattle breed in Brazil. The average number of offspring registered per sire ranged from about 12 (SHO) to 20 (DEV) and the mean generation interval ranged from about 6.0 (HER and SHO) to 6.4 (ANG) years. In the reference population (calves born in 2009 and 2010, plus those born in 2008 for SHO) the mean equivalent number of generations known ranged from about 7 (SHO) to 9 (HER). In the 4 breeds studied, nearly all animals born over the last few years are inbred, even though the mean level of inbreeding in the reference population is below 4% in all breeds. The rate of inbreeding per generation, computed from the individual increase in inbreeding, ranged from about 0.2 (ANG) to 0.5% (DEV), with a corresponding effective population size of 245 and 92, respectively, which is above the recommended minimum critical threshold. The number of founders/ancestors contributing with 50% of the reference population gene pool was 211/26 for ANG, 41/14 for DEV, 164/25 for HER, and 79/10 for SHO, with effective number of founders/ancestors/founder genomes of 470/68/36, 89/33/16, 289/59/30, and 200/28/18 for ANG, DEV, HER, and SHO, respectively. The genetic contribution of different countries to the gene pool of each breed indicated that, throughout the period studied, DEV genes originated predominantly from the United Kingdom, while for the other breeds there was a changing pattern over time. Until the 1970s Argentina was the major supplier of ANG, while HER and SHO genes were mostly from Uruguay, but since then the United States took the leading role as supplier of ANG, HER, and SHO genes to Brazil. Our results reveal a mild increase in inbreeding in all breeds studied, with effective population size estimates indicating that reasonable levels of genetic diversity have been maintained in all 4 breeds. Continuous monitoring of inbreeding trends and of parameters derived from probability of gene origin should be ensured to warrant the long-term maintenance of genetic diversity.

Bioeconomic model and selection indices in Aberdeen Angus cattle.

A bioeconomic model was developed to calculate economic values for biological traits in full-cycle production systems and propose selection indices based on selection criteria used in the Brazilian Aberdeen Angus genetic breeding programme (PROMEBO). To assess the impact of changes in the performance of the traits on the profit of the production system, the initial values ​​of the traits were increased by 1%. The economic values for number of calves weaned (NCW) and slaughter weight (SW) were, respectively, R$ 6.65 and R$ 1.43/cow/year. The selection index at weaning showed a 44.77% emphasis on body weight, 14.24% for conformation, 30.36% for early maturing and 10.63% for muscle development. The eighteen-month index showed emphasis of 77.61% for body weight, 4.99% for conformation, 11.09% for early maturing, 6.10% for muscle development and 0.22% for scrotal circumference. NCW showed highest economic impact, and SW had important positive effect on the economics of the production system. The selection index proposed can be used by breeders and should contribute to greater profitability.

Percentage depth dose evaluation in heterogeneous media using thermoluminescent dosimetry.

The purpose of this study is to investigate the influence of lung heterogeneity inside a soft tissue phantom on percentage depth dose (PDD). PDD curves were obtained experimentally using LiF:Mg,Ti (TLD-100) thermoluminescent detectors and applying Eclipse treatment planning system algorithms Batho, modified Batho (M-Batho or BMod), equivalent TAR (E-TAR or EQTAR), and anisotropic analytical algorithm (AAA) for a 15 MV photon beam and field sizes of 1 x 1, 2 x 2, 5 x 5, and 10 x 10 cm 2 . Monte Carlo simulations were performed using the DOSRZnrc user code of EGSnrc. The experimental results agree with Monte Carlo simulations for all irradiation field sizes. Comparisons with Monte Carlo calculations show that the AAA algorithm provides the best simulations of PDD curves for all field sizes investigated. However, even this algorithm cannot accurately predict PDD values in the lung for field sizes of 1 x 1 and 2 x 2 cm 2 . An overdosage in the lung of about 40% and 20% is calculated by the AAA algorithm close to the interface soft tissue/lung for 1 x 1 and 2 x 2 cm 2 field sizes, respectively. It was demonstrated that differences of 100% between Monte Carlo results and the algorithms Batho, modified Batho, and equivalent TAR responses may exist inside the lung region for the 1 x 1 cm 2 field.

Management of breast cancer patients failing adjuvant chemotherapy with adriamycin-containing regimens.

Sixty-two patients with breast cancer treated with Adriamycin-containing adjuvant chemotherapy developed recurrent disease. Four patients refused to take any form of systemic therapy at the time of relapse. Fifty-eight patients were managed with various treatment modalities, and of these 33 (57%) achieved on objective remission, 11 (19%) had stable disease and 14 patients (24%) did not respond to any form of therapy. Twenty-four patients received more than one treatment modality. Thirty-eight patients were treated with chemotherapy and 35 received endocrine therapy. Eight of 20 patients (40%) achieved objective remission upon retreatment with higher dose of 5-fluorouracil, Adriamycin, and cyclophosphamide at time of relapse, and seven of 18 patients (38%) treated with other chemotherapeutic agents showed objective remission. Fourteen of 35 patients (40%) achieved objective remission with hormonal therapies. The median survival from first relapse was 15 months for all patients, and was 25.7 months for responding patients. Survival was significantly longer in asymptomatic patients compared with those who were symptomatic from recurrent disease.

Postoperative adjuvant chemotherapy with fluorouracil, doxorubicin, cyclophosphamide, and BCG vaccine. A follow-up report.

Two hundred twenty-two patients with stage II or III breast cancer following regional therapy were treated with a combination of fluorouracil, doxorubicin hydrochloride (Adrimycin), cyclophosphamide, and BCG vaccine. At 54 months of study (median follow-up, 30 months), the estimated proportions remaining disease-free two and three years after surgery were 83%and 78%, respectively, in the chemotherapy group and 64% and 55%, respectively, in 151 historical control patients. Estimated two- and three-year survival rates were 93% and 89%, respectively, in the chemotherapy group and 84% and 58%, respectively, in the control patients. Congestive heart failure has developed in three patients, possibly related to the use of doxorubicin. Adjuvant chemotherapy with these drugs was effective in prolonging the disease-free interval and survival of patients irrespective of menopausal status, degree of nodal involvement, or stage of the disease.

Chemotherapy for advanced Kaposi sarcoma.

Kaposi sarcoma is a rare disorder, usually controlled with conservative localized treatment. However, prognosis is serious for patients with aggressive cutaneous disease, and aminous for those with visceral involvement. Two cases of advanced Kaposi sarcoma are reviewed to illustrate a chemotherapeutic approach to patients with this disease. The first case represents a verified response of visceral Kaposi sarcoma to chemotherapy. The second provides an example of the control of aggressive dermatologic disease.