Effect of cyclodextrin-loaded cholesterol conjugates on plasma membrane viability of Piau swine breed frozen/thawed spermatozoa.

The objective of this study was to investigate the effect of cyclodextrin-loaded cholesterol conjugates addition to freezing extenders on plasma membrane viability of frozen-thawed spermatozoa of the Piau swine breed. Twenty semen samples were used from five males. The freezing extender was based on lactose-egg yolk extender, added to 2% glycerol, 3% dimethylacetamide. The addition of cyclodextrin-loaded cholesterol conjugates was performed after centrifugation, when semen was diluted with the cooling extender. Four groups were subjected to the following treatment: without addition (group 1); 1.5 mg of cyclodextrin-loaded cholesterol/120 × 10(6) sperm (group 2); 1.5 mg of cyclodextrin-loaded cholestanol/120 × 10(6) sperm (group 3); 1.5 mg of cyclodextrin-loaded desmosterol/120 × 10(6) sperm (group 4). To check post-thawing sperm quality sperm motility and sperm morphology evaluation were used. Additionally, to check sperm viability the hypoosmotic swelling test, supravital staining, and fluorescent assay were used. The mean values recorded for total sperm motility of semen immediately after thawing were 54.5 ± 5.8, 55.5 ± 5.3, 53.7 ± 6.7, and 52.5 ± 6.6% respectively for groups one to four, without difference between themselves (p > 0.05). Regarding fluorescent assay the results were 28.3 ± 13.2, 26.9 ± 12.2, 22.2 ± 11.4, and 32.0 ± 15.3% respectively for groups one to four, also without difference between groups (p > 0,05). Similarly, complementary tests for evaluating the integrity and functionality of the plasma membrane showed no difference between treatments (p > 0.05). In conclusion, use of cyclodextrin-loaded cholesterol conjugates added to the plasma membrane of sperm did not demonstrate any additive effect on increasing and/or maintaining sperm motility.

Cryopreservation of Piau-Breed Wild Boar Sperm: Assessment of Cooling Curves and Centrifugation Regimes.

This study aimed to assess the effects of different cooling curves and centrifugation regimes used in cryopreservation protocols on the post-thaw viability of Piau-breed wild boar (Sus scrofa) sperm using in vitro assessment tests. Two centrifugations (800 g for 10 min and 2400 g for 3 min) and two cooling curves (conventional cooling using nitrogen vapour - freezing 1 and automated cooling using a programmed freezing machine - freezing 2) were tested. Therefore, the treatments were divided into M3 - centrifugation at 2400 g for 3 min and freezing 2; M10 - centrifugation at 800 g for 10 min and freezing 2; R3 - centrifugation at 2400 g for 3 min and freezing 1; and R10 - centrifugation at 800 g for 10 min and freezing 1. No significant differences (p > 0.05) between treatments occurred post-thawing regarding the total sperm motility means recorded. The mean values of the different treatments were not different from each other regarding the supravital staining (SV), hypo-osmotic test (HO), sperm-egg binding assay or sperm morphology. This study showed that both the cooling curve and the centrifugation regime affected the quality of post-thaw sperm, and centrifugation for shorter times and cooling curves using automated cooling are the most suitable for minimizing sperm injury.

Sexual precocity of Nellore bulls that are offspring of super precocious, precocious and normal cows in extensive farming conditions.

The objective of this work was to verify that mothers classified as super precocious (M1) and precocious (M2) produce more precocious bulls than females classified as normal (M3). This study included 21,186 animals with an average age of 21.29 ± 1.77 months that underwent a breeding soundness evaluation from 1999 to 2008. Of these animals, 2019, 6059 and 13,108 were offspring of M1, M2 and M3 females, respectively. In the breeding soundness examination, the animals were classified as sound for reproduction, sound under a natural mating regime, unsound for reproduction and discarded. To compare the averages obtained for each category of mother within the individual breeding soundness classes, a chi-square test with a 5% error probability was used, considering the effects of year and month of birth and farm. For the three classes of mothers (M1, M2 and M3), 67.26, 67.22 and 64.16% of bull calves were considered sound for reproduction and 19.71, 19.46 and 21.90% were considered unsound for reproduction, respectively. There was no difference in the frequency of animals that were sound for reproduction under the natural breeding regime between the three classes of mothers (8.87, 9.31 and 9.19%, respectively). There was a difference between the numbers of precocious and normal females that were discarded, with frequencies of 4.01 and 4.75%, respectively (p < 0.05). There were differences in year and month of birth and farm between super precocious and precocious cows in relation to the breeding soundness classification of the animals. It was concluded that the bull offspring of super precocious and precocious cows presented a higher percentage of approval in the breeding soundness examination than the bull offspring of normal cows, demonstrating that the selection for precocity of females has contributed to an increase in the sexual precocity of the herd in relation to the sexual maturity of bulls.

Radon dose assessment in underground mines in Brazil.

Underground miners are internally exposed to radon, thoron and their short-lived decay products during the mineral processing. There is also an external exposure due to the gamma emitters present in the rock and dust of the mine. However, the short-lived radon decay products are recognised as the main radiation health risk. When inhaled, they are deposited in the respiratory system and may cause lung cancer. To address this concern, concentration measurements of radon and its progeny were performed, the equilibrium factor was determined and the effective dose received was estimated in six Brazilian underground mines. The radon concentration was measured by using E-PERM, AlphaGUARD and CR-39 detectors. The radon progeny was determined by using DOSEman. The annual effective dose for the miners was estimated according to United Nations Scientific Committee on the Effects of Atomic Radiation methodologies. The mean value of the equilibrium factor was 0.4. The workers' estimated effective dose ranged from 1 to 21 mSv a(-1) (mean 9 mSv a(-1)).

Effect of different cryo-protectants on the viability of frozen/thawed semen from boars of the Piau breed.

The objective of this study was to evaluate the effect of different cryo-protectants (glycerol, dimethylacetamide and dimethylformamide alone or combined and added to lactose-egg yolk extender) on the viability of frozen/thawed semen from the Piau breed as assessed by in vitro testing. Frozen semen samples (n=20) were used from five male swine. Five different freezing extenders, including 2% glycerol (Group 1 - G), 2% glycerol and 3% dimethylacetamide (Group 2 - GA), 2% glycerol and 3% dimethylformamide (Group 3 - GF), 5% dimethylacetamide (Group 4 - A) and 5% dimethylformamide (group 5 - F), were evaluated. To assess post-thawing sperm quality, sperm motility and morphology were evaluated. Sperm viability was determined using the hypoosmotic swelling test, supravital staining, and a fluorescent assay (carboxyfluorescein diacetate and propidium iodide). The mean total sperm motility of semen immediately after thawing was 46.2±1.3, 57.7±1.5, 53.2±2.1, 51.7±1.2, and 46.5±1.6% for groups 1-5, respectively. Groups 2 (GA) and 3 (GF) had greater motility values (P<0.05). Fluorescent assay values of 22.3±2.3%, 35.2±3.7%, 30.8±3.4%, 36.6±3.7%, and 26.5±3.8% were obtained for Groups 1-5, respectively, showing that Group 4 (A) sperm had greater viability than those from Group 1 (G), although there was no differences between the other treatments (P>0.05). The other complementary tests (hypoosmotic swelling test and supra-vital staining) demonstrated that sperm in Groups 2 (GA), 3 (GF) and 4 (A) had the greatest viability and there were no significant differences among these three groups (P>0.05). The most effective cryo-protectant combinations likely minimized and controlled the deleterious processes that occur in the sperm cell during freezing/thawing, thus improving post-thawing sperm viability. In conclusion, the combination of amides (3%) and glycerol (2%) or dimethylacetamide (5%) alone were more efficient at cryo-protection than glycerol alone for semen freezing in the Piau swine breed.

Follicular dynamics and gene expression in granulosa cells, corpora lutea and oocytes from gilts of breeds with low and high ovulation rates.

Follicular dynamics and the expression of candidate genes using real-time polymerase chain reaction (PCR) were compared during the oestrous cycle of pig breeds with high (commercial line; n=24) and low (local Brazilian Piau; n=21) ovulation rates and prolificacy. Gilts were killed on Days 0, 4, 10 and 18 of the oestrous cycle and visible ovarian follicles were classified by follicular diameter. Recovered cumulus-oocyte complexes were classified as normal or atretic and frozen in liquid nitrogen until RNA extraction. Low ovulation rates and/or prolificacy in Piau gilts was associated with a different pattern of follicle development, with lower numbers of small follicles on Day 18, fewer large follicles on Days 0 and 18 (P≤0.05) and a higher proportion of atretic follicles on Days 0 and 18 (P≤0.05). Compared with commercial line gilts, less-prolific Piau gilts exhibited higher expression of apoptotic genes during luteolysis (CASP3 and FASL; P≤0.05), decreased expression of TGFBR2 and BAX mRNA in the corpus luteum (P≤0.05), higher expression of apoptotic genes (FAS, BCL2 and CASP8; P≤0.05) in granulosa cells and a greater abundance (P≤0.05) of genes controlling oocyte-secreted factors (GDF9, BMP15 and BMP6), suggesting underlying mechanisms controlling differences in follicular development, ovulation rate and inherent prolificacy in this pig breed.

Estimativas de herdabilidades e correlações genéticas entre características reprodutivas em touros da raça Nelore / Genetic correlations and heritability estimates of reproductive traits of Nellore bulls

Foram obtidas estimativas de variância fenotípica, genética e residual, herdabilidades e correlações genéticas para as características reprodutivas em 5.903 animais da raça Nelore. O modelo experimental utilizado foi o método de máxima verossimilhança restrita livre de derivadas. Os valores de herdabilidade foram de 0,24±0,05 para perímetro escrotal aos 450 dias de idade e de 0,37±0,05 aos 21 meses de idade, na ocasião do exame andrológico; de 0,24±0,05 e 0,26±0,05 para comprimento dos testículos esquerdo e direito; de 0,29±0,05 e 0,31±0,05 para largura dos testículos esquerdo e direito; de 0,12±0,04 para formato testicular; de 0,33±0,06 para volume testicular; de 0,11±0,03 para turbilhonamento; de 0,08±0,03 para motilidade e de 0,05±0,02 para vigor espermático; de 0,20±0,04, 0,03±0,02 e 0,19±0,04 para defeitos espermáticos maiores, menores e totais, respectivamente. As características biométricas testiculares apresentaram valores de herdabilidade moderados a altos, enquanto as características seminais valores baixos. Correlações genéticas entre perímetro escrotal com todas as características reprodutivas foram favoráveis, o que sugere o perímetro escrotal como característica de escolha na seleção de touros.

Estimates of phenotypic, genetics and residual variances for reproductive traits in 5903 Nellore bulls were obtained. The experimental model used was multiple trait derivative-free restricted maximum likelihood. The values obtained for heritability were 0.24±0.05 for scrotal circumference at 450 days of age and 0.37±0.05 at 21 months for age at the time of the breeding soundness evaluation; 0.24±0.05 and 0.26±0.05 for left and right testicle length; 0.29±0.05 and 0.31±0.05 for left and right testicle width; 0.12±0.04 for testicle format; 0.33±0.06 for testicle volume; 0.11±0.03 for gross motility; 0.08±0.03 for individual motility and 0.05±0.02 for spermatic vigor; 0.20±0.04, 0.03±0.02 and 0.19±0.04 for larger defects, smaller defects and total defects, respectively. The values for heritability for testicular biometric characteristics were moderate to high while the seminal characteristics, presented low values. Genetic correlations between scrotal circumference with all the reproductive traits were favorable, suggesting the scrotal circumference as a feature of choice in the selection of bulls.

Heritability estimate and genetic correlations of reproductive features in Nellore bulls, offspring of super precocious, precocious and normal cows under extensive farming conditions.

The present work aimed to estimate heritability and genetic correlations of reproductive features of Nellore bulls, offspring of mothers classified as superprecocious (M1), precocious (M2) and normal (M3). Twenty one thousand hundred and eighty-six animals with average age of 21.29 months were used, evaluated through the breeding soundness evaluation from 1999 to 2008. The breeding soundness features included physical semen evaluation (progressive sperm motility and sperm vigour), semen morphology (major, minor and total sperm defects), scrotal circumference (SC), testicular volume (TV) and SC at 18 months of age (SC18). The components of variance, heritability and genetic correlations for and between the features were estimated simultaneously by restricted maximum likelihood, with the use of the vce software system vs 6. The heritability estimates were high for SC18, SC and TV (0.43, 0.63 and 0.54; 0.45, 0.45 and 0.44; 0.42, 0.45 and 0.41, respectively for the categories of mothers M1, M2 and M3) and low for physical and morphological semen aspects. The genetic correlations between SC18 and SC were high, as well as between these variables with TV. High and positive genetic correlations were recorded among SC18, SC and TV with the physical aspects of the semen, although no favourable association was verified with the morphological aspects, for the three categories of mothers. It can be concluded that the mother's sexual precocity did not affect the heritability of their offspring reproduction features.

Reproductive parameters of Mangalarga Marchador mares in a commercial embryo transfer programme.

The objective of this study is to evaluate the reproductive efficiency in donors and recipient Mangalarga Marchador mares in commercial programmes of embryo transfer (ET) and the effects of some reproductive characteristics and ET methodology on conception rates in the recipient mares. A total of 1140 flushing procedures were performed and 830 embryos (72.8%) were recovered. There were no differences between the rates of embryonic recovery in the different breeding seasons (p > 0.05) and 92.8% of the recovered embryos were 8-9 days old. There was no difference in the embryonic recovery regarding the collection order from the first to the ninth embryo collection along the breeding season, as well as among mares inseminated during the foal heat or subsequent cycles (p > 0.05). Pregnancy rates observed in the total period of all reproductive seasons at 15, 30, 45 and 60 days of pregnancy were 73.4, 69.9, 66.7 and 64.5%, respectively. Differences in pregnancy rate and early embryonic loss rates were not observed between embryos transferred immediately after collection (66.8% and 13.5%) and embryos transported at room temperature for periods of < 1 h (62.9% and 14.4%; p > 0.05). Pregnancy rates were higher when the interval between ovulations of donor and recipient mares remained between -3 and -2 days (p < 0.05), and the lowest rates were observed for intervals of -6 days (p < 0.05) with intermediary values for intervals of -1, 0 and +1 (p > 0.05). Embryonic loss rates, however, did not differ between intervals of ovulation's synchronism between donor and recipient mares (p > 0.05). This flexibilization in the ovulatory synchronism between donor and recipient mares optimizes the use of recipient mares, thus reducing costs and facilitating management of horse breeding farms.

Immotile short-tail sperm defect in Nelore (Bos taurus indicus) breed bulls.

This case study reported the presence of short tail sperm defect in the semen of three Nelore breed bulls. The sperm presented 0% of motility in the three animals evaluated and a total of 70%, 61% and 34% of pathologies of the intermediate piece of the tail respectively for animals 1, 2 and 3. It was identified that animals 2 and 3 had high degree of inbreeding, although no relationship was found with animal 1. Animal 2 was the only one that presented inbreeding coefficient (6.25%). His half-sib (animal 3) and animal 1, from the same herd, had shown no inbreeding, showing that inheritance is not the only determinant factor for its incidence on Nelore males.

Comparison and critical appraisal of dengue clinical guidelines and their use in Asia and Latin America.

The World Health Organization (WHO) dengue classification scheme for dengue fever (DF) and dengue haemorrhagic fever (DHF)/dengue shock syndrome (DSS) has been adopted as the standard for diagnosis, clinical management and reporting. In recent years, difficulties in applying the WHO case classification have been reported in several countries. A multicenter study was carried out in Asia and Latin America to analyze the variation and utility of dengue clinical guidelines (DCGs) taking as reference the WHO/PAHO guidelines (1994) and the WHO/SEARO guidelines (1998). A document analysis of 13 dengue guidelines was followed by a questionnaire and Focus Group discussions (FGDs) with 858 health care providers in seven countries. Differences in DCGs of the 13 countries were identified including the concept of warning signs, case classification, use of treatment algorithms and grading into levels of severity. The questionnaires and FGDs revealed (1) inaccessibility of DCGs, (2) lack of training, (3) insufficient number of staff to correctly apply the DCGs at the frontline and (4) the unavailability of diagnostic tests. The differences of the DCGs and the inconsistency in their application suggest a need to re-evaluate and standardise DCGs. This applies especially to case classification and case management.

[Differential patterns of neonatal and post-neonatal mortality rates in Goiânia, Brazil, 1992-1996: use of spatial analysis to identify high-risk areas]. / Diferenças no padrão de ocorrência da mortalidade neonatal e pós-neonatal no Município de Goiânia, Brasil, 1992-1996: análise espacial para identificação das áreas de risco.

The aim of this study was to investigate the spatial pattern of neonatal and post-neonatal mortality in the city of Goiânia, Central Brazil. Analyses were based on linked birth and death certificates relating to 101,000 in-hospital live births from mothers residing in the city of Goiânia over the 1992-1996 period. Overall neonatal and post-neonatal mortality probabilities were calculated using the linked database. The empirical Bayes method was applied to smooth the estimated rates and minimize random fluctuation. Spatial units of analysis were 65 urban districts, corresponding to the urban planning sectors. The following exploratory spatial analyses were applied: "global" Moran's I statistic, local Moran LISA map, and Gi* local statistics. For both neonatal and post-neonatal mortality there was statistically significant spatial autocorrelation. Results of post-neonatal mortality showed a high-risk cluster located on the outskirts of the city. For the neonatal period, a heterogeneous mortality pattern was found with high-risk districts in all regions, including central areas.