Greenhouse gas emissions between 1993 and 2002 from land-use change and forestry in Mexico

In this paper we present the Mexican inventory of greenhouse gas (GHG) emissions from the land-use sector. It involved integration of forest inventory, land-use and soil data in a GIS to estimate the net flux of GHG between 1993 and 2002.     

Conservation of freshwater biodiversity in key areas of the Colombian Amazon

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Effects of dredging operations on sediment quality: contaminant mobilization in dredged sediments from the Port of Santos, SP, Brazil

Background, aim, and scope  

Contaminated sediments are a worldwide problem, and mobilization of contaminants is one of the most critical issues in environmental risk assessment insofar as dredging projects are concerned. The investigation of how toxic compounds are mobilized during dredging operations in the channel of the Port of Santos, Brazil, was conducted in an attempt to assess changes in the bioavailability and toxicity of these contaminants.     

Effects of adrenocorticotropic hormone challenge and age on hair cortisol concentrations in dairy cattle

Dairy cattle suffer stress from management and production; contemporary farming tries to improve animal welfare and reduce stress. Therefore, the assessment of long-term hypothalamic-pituitary-adrenal function using non-invasive techniques is useful. The aims in this study were: to measure cortisol concentration in cow and calves hair by radioimmunoassay (RIA), to test cortisol accumulation in bovine hair after adrenocorticotropic hormone (ACTH) challenges, and determine the influence of hair color on cortisol concentrations. Fifteen Holstein heifers were allotted to 3 groups (n = 5 each): in control group (C), just the hair was sampled; in the saline solution group (SS), IV saline solution was administered on days 0, 7, and 14; and the ACTH group was challenged 3 times with ACTH (0.15 UI per kg of body weight) on days 0, 7, and 14. Serum samples from the SS and ACTH groups were obtained 0, 60 and 90 min post-injection. Serum cortisol concentration was greater 60 and 90 min after injection with ACTH. Hair was clipped on days 0, 14, 28, and 44. Hair cortisol was methanol extracted and measured by RIA. Hair cortisol was preserved for 11 mo. Hair cortisol concentrations in the ACTH group were greater than in the saline and control groups on days 14 and 28, but not on day 44. Concentrations were greater in calves than in cows and greater in white hair than in black hair. Cortisol accumulated in bovine hair after ACTH challenges, but the concentration was affected by both age and hair color. If hair color effects are taken into account, assessing cortisol concentration in hair is a potentially useful non-invasive method for assessing stress in cattle.     

The effect of selected microbial strains on internal milieu of broiler chickens after peroral administration

The aim of this work was to investigate the effect of probiotic preparation with multi-strains composition (Lactobacillus delbrueckii ssp. bulgaricus LAT 187, Lactobacillus acidophilus LAT 180, Lactobacillus helveticus LAT 179, Lactobacillus delbrueckii ssp. lactis LAT 182, Streptococcus thermophilus LAT 205 and Enterococcus faecium E 253) on internal milieu, antioxidant status and body weight of broiler chickens. Chickens were divided into three groups (C, control; E1 and E2, experimental groups). Experimental chickens received the probiotic preparation in drinking water. Probiotic preparation caused a significant increase of serum calcium and potassium content. In the group with higher dose of probiotic strains serum triglycerides level decreased. Total antioxidant status in groups with addition of probiotic strains showed higher values in comparison to control group. Serum albumin level was found to increase after consumption of probiotic preparation in group with higher dose of probiotic strains. Probiotic strains improved body weight in last observed weeks of feeding.     

Histological effects on the kidney,spleen, and liver of Nile tilapia Oreochromis niloticus fed different concentrations of probiotic Lactobacillus plantarum

Tropical Animal Health and Production - The aims of this study were to evaluate the inclusion of different concentrations of Lactobacillus plantarum in Nile tilapia diet and to verify histological...     

Antigenotoxicity and Antioxidant Activity of Acerola Fruit (Malpighia glabra L.) at Two Stages of Ripeness

Genotoxic and antigenotoxic effects of acerola fruit at two stages of ripeness were investigated using mice blood cells. The results show that no ripeness stage of acerola extracts presented any genotoxic potential to damage DNA (Comet assay) or cytotoxicity (MTT assay). When antigenotoxic activity was analyzed, unripe fruit presented higher DNA protection than ripe fruit (red color) extract. The antioxidant capacity of substances also showed that unripe samples inhibit the free radical DPPH more significantly than the ripe ones. The results about determination of compounds made using HPLC showed that unripe acerola presents higher levels of vitamin C as compared to ripe acerola. Thus, vitamin C and the complex mixture of nutrients of Malpighia glabra L., and especially its ripeness stages, influenced the interaction of the fruit extract with the DNA. Acerola is usually consumed when ripe (red fruit), although it is the green fruit (unripe) that has higher potential as beneficial to DNA, protecting it against oxidative stress.     

Effects of the herbicide LASSO MTX (alachlor 42% W/V) on biometric parameters and liver biomarkers in the common carp (Cyprinus carpio)

The aim of the study was to evaluate the effect of subchronic exposure to the herbicide LASSO MTX (alachlor 42% W/V) on biometric parameters and important liver biomarkers in the common carp (Cyprinus carpio). One year old fish were exposed for 28 days to LASSO MTX added to the tank water at concentrations of 240 and 2400 μg L⁻¹. The exposure did not affect fish biometric parameters. Glutathione-S-tranferase (GST) activity in liver (hepatopancreas) remained unchanged in exposed fish when compared to controls. However, significant induction of total cytochrome P 450 (CYP 450), ethoxyresorufin-O-deethylase (EROD) activity and elevated glutathione (GSH) in liver of exposed fish were detected.     

Controlling Acid Drainage in a Pyritic Mine Waste Rock. Part I: Statistical Analysis of Drainage Data

Field experiments were conducted to evaluate the relativeeffectiveness of several covers and amendment techniques forpreventing or controlling acid generation in a pyritic minewaste rock. The covers and techniques consisted of water cover,soil cover, wood bark cover, limestone addition and phosphaterock addition. Water quality data (pH, sulphate, zinc and ironconcentrations) obtained from the experiments were analyzedusing two-way ANOVA (analysis of variance) with repeatedmeasurements. A 5% test of significance (p-value of 0.05) wasused in the analysis. The results suggested that the covers andamendments should be either compared on a time-by-time basis orgrouped into four, based on their performance: (i) water cover, (ii)1% and 3% limestone, (iii) clay, 1% and 3%PO₄, andcontrol (no cover), and (iv) wood bark. The results did not showany significant difference between the drainage quality from1% and 3% limestone-amended rocks. The drainage quality from the 1%and 3% phosphate and clay-covered rocks did not significantlydiffer from the control (unamended) rock. Water cover was foundto be the most effective, while the wood bark cover proved to bean ineffective method for controlling acid drainage in the wasterock. The statistical analysis also showed good replication inthe experiments, as no significant difference in the quality ofthe drainage from the replicates was observed.     

Computed tomography is a feasible method for quantifying bone density in Macaca mulatta

Osteopathologies are a result of advanced age and decreased bone density and represent a global health problem. It is therefore important to generate models for longitudinal studies of the pathophysiology in order to improve early diagnosis and develop preventive therapies. For this kind of research, the use of computed tomography (CT) to evaluate bone health offers advantages over other techniques since it provides more complete information. The aim of this prospective, pilot study was to obtain measurements of the left femur from a population in captivity of 32 rhesus monkeys (Macaca mulatta) in order to standardize the model for future research. Healthy subjects from 5 to 28 years old were chosen. Three groups with different ages were formed as follows: (1) 5–9 years, (2) 10–19 years, and (3) 20–28 years. Semi‐automatic segmentation by threshold defined the regions of interest, which were subdivided in the range of 300–700 Hounsfield units (HU) for trabecular bone and >700 HU for cortical bone. Then, the proportional ratios of the volumes of trabecular bone and cortical bone were obtained. Significant differences (analysis of variance test) in the averages of Hounsfield units, cortical, and trabecular bone proportions from each age group proved that a decrease in bone density begins at approximately 20 years of age. The values presented here, as well as the method to obtain them from CT scans, can be used as a baseline in a primate model for long‐term research in bone pathology diagnosis and treatment.