Environmental and genetic variation of the effective radiative properties of the coat of Holstein cows under tropical conditions

Morphological characteristics, coat effective radiative properties, and the percentage of white colour were measured in the coats of 973 Holstein cows, and estimates of the genetic parameters were obtained for these traits, except morphological characteristics. The results showed that white coats are more dense with long, thin hairs, while the black coats are less dense with short, thick hairs. Effective transmissivity is greater in the less-dense coats with short, thin hairs, independently of coat colour. Effective reflectivity depends more on the variation in the radiative properties of the coat and skin surface rather than on the morphological characteristics of the coat. Effective absorptivity is greater in black and dense coats with long, thick hairs, than in the white and less-dense coat with short, thin hairs. All heritability estimates were of low magnitude, except for the percentage of white coat colour.     

Pastoralism and plant cover in the lower Shabelle Region,Southern Somalia

A vegetation and rangeland survey has been carried out in the lower Shabelle region, Southern Somalia, with the aim of evaluating the natural vegetation as a source of forage for grazing animals. In this framework, four different vegetation types have been recognized and mapped using remote sensing techniques; general vegetation characteristics, mainly floristic and physiognomic aspects, are described. Dynamic relationships between these vegetation types are also outlined.     

Suppressive activity of some glucosinolate enzyme degradation products on Pythium irregulare and Rhizoctonia solani in sterile soil

Glucosinolate degradation products (GLDPs), mainly isothiocyanates, obtained by myrosinase‐catalysed hydrolysis of glucosinolates (GLs), are an important group of natural bioactive substances. The fungitoxic activity of four GLDPs, chosen on the basis of their side‐chain structures, was assayed against Pythium irregulare and Rhizoctonia solani. The effectiveness of the degradation products (DPs) of sinigrin (alkenyl GL), epi‐progoitrin (hydroxy‐alkenyl GL), glucoiberin and glucoerucin (thiofunctionalised GLs) in inhibiting P irregulare oospore germination and R solani soil colonisation were tested in a closed system, using an artificially infected soil. The fungitoxic activity of these GLDPs varied according to their side‐chain structure. As in previous in vitro studies, the thiofunctionalised GLDPs were found the most effective, producing complete inhibition of P irregulare oospore germination (0.01 µmole g⁻¹ soil) and R solani soil colonisation (0.5 µmole g⁻¹ soil), but even sinigrin DP showed a fungitoxic activity higher than that of epi‐progoitrin DP. © 2000 Society of Chemical Industry     

Ontogeny of hepatic methionine catabolic enzyme activities (Transmethylation and Transsulphuration) and associated physiological amino acids in E10-21 chick embryos and D1-49 broilers

Developmental changes in hepatic methionine adenosyltransferase, cystathionine β-synthase, cystathionase, and glycine N-methyltransferase were determined in broiler chick embryos and hatched chicks by using radiometric and spectrometric methods. Hepatic free methionine, S-adenosylmethionine, S-adenosylhomocysteine, homocysteine, cystathionine, and cysteine levels were also investigated. Results showed an increase in hepatic MAT activity from E10 to E21 during embryogenesis, suggesting greater transmethylation rates throughout the rapid embryonic growth and development period. A strong positive correlation between embryo BW and MAT activity also supports this idea. The MAT specific activity continued to increase after hatching, but there was a negative correlation between chick BW and MAT activities from D1 to D49. This may indicate different MAT isozymes exist for chick embryo hepatic tissue compared to hepatic tissue of hatched chick and growing broilers. The developmental pattern of MAT isozymes could be critical for methionine metabolism to cope with the demand imposed on the embryo, chicks, and growing broilers. Additionally, the specific activity of hepatic CBS in chick embryos was determined to be lower compared to that observed in older broilers (35 and 49 days). Since liver CBS specific activity is at the lowest point from D1-7 in young chicks, the ability to convert adequate homocysteine to cysteine through transsulphuration may be limiting for cysteine synthesis at this time. Steady-state hepatic homocysteine levels in chick embryos and chicks may be a function of the rates of homocysteine formation, remethylation, and catabolism via the transsulphuration pathway. The present study indicates young chicks from D1 to D7 may have a limited ability for adequate transsulphuration; therefore, dietary cystine may be needed for optimum performance.     

A habitat model for brown bear conservation and land use planning in the central Apennines

We investigated the brown bear habitat suitability in an 8000 km² study area encompassing Abruzzo, Latium, and Molise regions in central-southern Italy. Based on long-term field surveys and published records, we classified bear habitat as occupied or unoccupied in 92 out of 320 sample squares (5 × 5 km). For each sample square 36 habitat variables were measured from topographic maps and Corine land-cover III level digital maps. The influence of habitat features on bear presence was investigated by multivariate and one-way analyses of variance and by logistic regression analysis. The logistic model correctly classified 95.5% of sample squares of bear presence and 93.8% of those where bears were absent. Average altitude, deciduous woodlands and ecotone length, showed a positive relationship with bear presence, whereas vineyard-olive groves and shrublands were negatively correlated with bear presence. No specific land management guidelines or strategies exist for bear conservation in central Italy, based on knowledge of habitat-population relationships. The landscape scale habitat model we developed could be useful to predict bear occurrence, to identify critical areas for a brown bear conservation strategy, and to enhance the arrangement of the protected areas network for the conservation of this species.     

Use of genetic markers to identify the illegal trade of billfish in the second largest fishing warehouse of Latin America

1. Billfish are oceanic pelagic species that are often caught by tuna fleets and are of great interest for sport fishing. Two species of billfish have specific legislation prohibiting their marketing and export in Brazil.
2. DNA barcoding is a universal system of molecular identification based on a sequence of mitochondrial DNA cytochrome oxidase subunit I (COI), which serves as a diagnostic genomic marker in each species.
3. The barcode DNA technique was used to identify billfish marketed in the second largest fishing warehouse in Latin America, the CEAGESP (Companhia de Entrepostos e Armazéns Gerais de São Paulo), located in São Paulo, Brazil. Seventy‐nine samples of billfish were collected during three inspection visits carried out by Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis.
4. After DNA sequencing, 70 samples (88.60%) were identified to the species level; 21 (30.00%) were identified as Xiphias gladius, 43 (61.42%) as Istiophorus platypterus and six (8.57%) as Kajikia albida. The sale of this latter species is prohibited in Brazil and it is considered Vulnerable on the list of endangered species of the IUCN and in the official list of species of endangered Fauna – Fish and Aquatic Invertebrates.
5. Molecular analyses proved to be very efficient at uncovering irregularities in the identification of the white marlin (K. albida), which was traded illegally in CEAGESP, demonstrating the ineffectiveness of the current monitoring techniques used and emphasizing the need for the adoption of better public policies for the conservation of the species.

     

Chemical composition and antioxidant, antimicrobial, and antifungal activities of the essential oil of Achillea ligustica all

The chemical composition of the essential oil from flowering tops of Achillea ligustica All. was studied. Samples were collected in different localities of Sardinia (Italy) and hydrodistilled both with Clevenger-type and with simultaneous distillation-extraction apparatus. The yields ranged between 0.88 +/- 0.06 and 0.43 +/- 0.02% (vol/dry wt). The essential oils were analyzed by GC-MS, and a total of 96 components were detected. From a qualitative point of view, irrelevant differences between samples were observed. Strong chemical variability depending on the origin of the samples was observed. The major compounds found were santolina alcohol (6.7-21.8%, for the first time detected in A. ligustica), borneol (3.4-20.8%), sabinol (2.1-15.5%), trans-sabinyl acetate (0.9-17.6%), alpha-thujone (0.4-25.8%), and, among sesquiterpenes, viridiflorol (0.7-3.6%). No significant differences were detected between essential oils extracted by hydrodistillation and simultaneous distillation-extraction with CH2Cl2 and n-hexane. Antioxidant activity as DPPH radical scavenging activity was expressed in TEAC and ranged between 0.40 and 0.88 mmol/L. The antimicrobial and antifungal activities were investigated on Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, Penicillium commune, Fusarium oxysporum, Rizoctonia solani, and Aspergillus flavus, showing low activity.     

Natural Biofilms in Freshwater Ecosystem: Indicators of the Presence of Polycyclic Aromatic Hydrocarbons

Hydrophobic organic compounds are common in the environment, especially in water bodies like rivers and lakes. Generally, due to their physico-chemical characteristics, mainly to hydrophobicity, these compounds are adsorbed by suspended material or other compartments which provide compatibility. Thus, compounds such as polycyclic aromatic hydrocarbons (PAHs) are rapidly adsorbed onto suspended material or even naturally occurring biofilms in water bodies. Biofilms can be defined as complex structures with cells and aggregates of cells. The extracellular polymers present empty spaces that can be filled by water. The biofilm is a sessile microbial community with several kinds of organisms such as bacteria, protozoa, fungi, algae, and extracellular polymeric substances, which may be found on almost any surface exposed to water. Here, biofilms were used to monitor the presence of PAHs in the Barigui River in Curitiba, Brazil. For the measurements and collection of representative microcoenoses, a biofilm sampling device was designed consisting of six glass plates installed in an open polyvinyl chloride pipe of 30?cm diameter and 60?cm length. The sampling device was exposed in the Barigui River for 2?weeks campaigns. The formed biofilm was treated and chemical analysis was performed for PAHs determination. The results showed that biofilms can trap most of the PAHs, especially those with high K _ow values (octanol?Cwater partition coefficient). Four campaigns were conducted. The total PAHs concentration ranged from 11,204.34?±?560.12 to 45,846.90?±?2,290.45?ng/g. According to the isomers ratio, the main source of PAHs in the first and second campaign was of pyrolytic origin, in other words, the PAHs were by-products from burning of light-refined oil products (gasoline and diesel oil). Meanwhile, the other campaigns revealed that the main source is of petrogenic origin. However, the possibility of both sources is not discarded considering the scenario studied and the records of sediments samples. Most of the investigations carried out focused on the loading of river sediments and suspended solids, but the biofilms might detect the amount that could be taken up by benthic organisms, for instance.