沿海防护林主要病虫害发生原因及防治对策

本文对日照沿海防护林17种主要病虫害发生原因进行了全面分析，提出了相应的防治对策。     

黄土高原丘陵沟壑区放牧林草地土壤团聚体性质研究

通过放牧试验的方法,研究土壤团聚体含量和破坏率,以探讨不同放牧强度、不同放牧畜种、不同放牧植被类型条件下表土的团聚体(＞ 0.25 mm)含量和破坏率.结果表明:放牧强度对土壤性质有影响,重度放牧下土壤团聚体含量最小;从畜牧羊种选择来看,绵羊相对于山羊来说对土壤结构破坏较小,土壤中团聚体含量较高;对于不同植被类型,放牧...     

Diagnosis of Eimeria species using traditional and molecular methods in field studies

The objective of this study was to identify and characterize species of Eimeria in broiler chickens using traditional morphological and pathological plus molecular (DNA amplification) diagnostic methodologies. Using a combination of those techniques it was possible to identify the presence of multiple circulating species in the flock as well as higher frequencies for some of them, especially Eimeria praecox and Eimeria maxima, which were identified in 100% of the flocks. The frequencies of the other species were Eimeria mitis and Eimeria necatrix (93.3%), Eimeria tenella (76,7%), Eimeria acervulina (56.7%) and Eimeria brunetti (16.7%). However using the lesion score, the most common species were E. maxima (46.7%), E. acervulina (30%), E. tenella (23.3%), and E. necatrix (10%). E. brunetti and E. praecox were not identified by using lesion score. DNA amplification had detection sensitivity for Eimeria species in the field samples of at least 20 oocysts. The implementation of DNA amplification as a routine diagnostic technique in aviaries can assist Eimeria population.     

Effect of zinc supplementation in pregnant mice during experimental Trypanosoma cruzi infection

Zinc is an essential micronutrient and has significant effects on human growth, development, and immune function. Zinc supplementation or deficiency may affect the course of infection. Zinc enhances immune response against a wide range of viral, bacterial, and parasitic pathogens. In the present study, we investigated the effects of zinc sulphate (ZnSO₄) supplementation (20 mg/kg/day) during pregnancy in mice, Swiss Webster strain infected by the Y strain of Trypanosoma cruzi. Oral supplementation of zinc sulphate in pregnant and non-pregnant infected animals did not affect the count of blood parasites as well as tissue parasitism in the heart, liver, and spleen. Zinc supplementation did not alter female body weight, the length of fetuses and neonates, placental size/weight and mortality rate. Among zinc supplied animals, no significant plasmatic zinc concentrations were observed. Concerning to tissue zinc concentrations, only the liver displayed enhanced values as compared to other organs. For placental parasitism, zinc supplied group displayed a significant decrease in amastigote burdens (P < 0.05). However due to the reduced number of parasite burdens in placenta of animals supplied with zinc, these data suggest that zinc was partially effective in up-regulating the host’s immune response against parasite, probably attenuating the infection in fetuses.     

Effect of association of fresh cassava root with corn silage in replacement for cactus cladodes on dairy cow performance

Tropical Animal Health and Production - The aim of this study was to investigate the replacement effect of cactus cladodes with cassava root and corn silage (CRCS) (0, 25, 50, 75, and 100%, dry...     

Application of platelet-rich plasma in the in vitro production of bovine embryos

Tropical Animal Health and Production - The aim of this study was to replace fetal bovine serum (FBS) with platelet-rich plasma (PRP) for in vitro production of bovine embryos. The maturation media...     

Linear and Poisson models for genetic evaluation of tick resistance in cross‐bred Hereford x Nellore cattle

Cattle resistance to ticks is measured by the number of ticks infesting the animal. The model used for the genetic analysis of cattle resistance to ticks frequently requires logarithmic transformation of the observations. The objective of this study was to evaluate the predictive ability and goodness of fit of different models for the analysis of this trait in cross‐bred Hereford x Nellore cattle. Three models were tested: a linear model using logarithmic transformation of the observations (MLOG); a linear model without transformation of the observations (MLIN); and a generalized linear Poisson model with residual term (MPOI). All models included the classificatory effects of contemporary group and genetic group and the covariates age of animal at the time of recording and individual heterozygosis, as well as additive genetic effects as random effects. Heritability estimates were 0.08 ± 0.02, 0.10 ± 0.02 and 0.14 ± 0.04 for MLIN, MLOG and MPOI models, respectively. The model fit quality, verified by deviance information criterion (DIC) and residual mean square, indicated fit superiority of MPOI model. The predictive ability of the models was compared by validation test in independent sample. The MPOI model was slightly superior in terms of goodness of fit and predictive ability, whereas the correlations between observed and predicted tick counts were practically the same for all models. A higher rank correlation between breeding values was observed between models MLOG and MPOI. Poisson model can be used for the selection of tick‐resistant animals.     

Chemical composition and larvicidal activity of the essential oils from Eupatorium betonicaeforme (D.C.) Baker (Asteraceae)

The volatile composition of the essential oils from leaves and roots of Eupatorium betonicaeforme (D.C.) Baker was analyzed by GC-MS. A total of 12 compounds were identified. beta-Caryophyllene (12.4-41.7%), alpha-humulene (11.7-14.6%), gamma-muurolene (10.4-19.0%), bicyclogermacrene (15.0-17.5%), 2,2-dimethyl-6-vinylchroman-4-one (10.3-25.5%), and 2-senecioyl-4-vinylphenol (8.5-41.0%) were the most prominent constituents. The former two compounds were isolated and characterized by spectroscopic data. The essential oils and the isolated compounds were tested against Aedes aegypti larvae survival. The results obtained show that the essential oil from roots and 2,2-dimethyl-6-vinylchroman-4-one (10.3-25.5%) could be considered as natural larvicidal agents.     

Traditional knowledge, genetic and morphological diversity in populations of Spondias tuberosa Arruda (Anacardiaceae)

Plant domestication is an evolutionary process whose artificial selection and management change the landscape, modeling plants to satisfy the human needs, affecting the phenotype component(s) of the species under manipulation. This study aimed at examining and comparing two rural communities: Malhada de Areia e Carão, municipally of Altinho, Pernambuco regarding the knowledge, perception of morphological variations (size fruit, flavor fruit, shape fruit, yield pulp and fruit color), morphological characteristics of preference at the time of collection; evaluation on the inter- and intrapopulation morphological differences of species and assessment of diversity, variability and local genetic structure of Spondias tuberosa populations under different management regimes based on the ISSR analysis. The results pointed to the maintenance of local genetic and morphological diversity, being it strongly related to the management practices of the species, especially the S. tuberosa tolerance in open areas for farming and pasture. Thus, it is emphasized the importance of this study in Brazil by being the first time that aspects related to management and perceived diversity, morphology and genetics of a highlighted perennial species from the semi-arid region of northeastern Brazil are evaluated from the perspective of domestication studies on its incipient status. Moreover, it provides interesting data that will contribute to the conservation strategies and breeding programs.