Strategies of supplementation of female suckling calves and nutrition parameters of beef cows on tropical pasture

The performance of female calves in creep feeding under different strategies of supplementation and milk production, intake, and digestibility of grazing Nellore and crossbred cows (Nellore?×?Holstein) during the dry-rainy transition season were assessed. Forty-four female beef suckling calves, with initial age between 90 and 150?days and average initial body weight of 117.7?±?4.3?kg, and their respective dams (24 Nellore and 20 crossbred) with average initial body weight of 417.5?±?8.3?kg, were used. The experimental treatments consisted of: control group-mineral mixture only; strategy 1-supplementation from 112?days prior to weaning (0.375?kg/animal/day); strategy 2-supplementation from 112?days prior to weaning, in increasing amounts of 0.15, 0.30, 0.45, and 0.60?kg/animal/day through the four experimental periods, respectively; and strategy 3-supplementation from 56?days prior to weaning (0.750?kg/animal/day). Calves from strategy 1 had greater (P??0.05) for nutrient digestibility among genetic types. It can be concluded that strategies of supplementation that present an equitable distribution of supplement provides greater weight gain in suckling female beef calves. Crossbred cows produce more milk and present greater DMI than Nellore cows. There are no differences in the nutrient digestibility between Nellore and Nellore × Holstein crossbred cows.     

Spatial relationship between human population density, land use intensity and biodiversity in the Czech Republic

We test a hypothesis about the spatial coincidence of human population density and species richness, and analyze effects of land conversion and ecosystem use on species richness and landscape diversity in human dominated Central European country, the Czech Republic. We calculated fraction of aboveground net primary productivity appropriated by humans and compared it to the species richness of vertebrate, invertebrate and plant groups and to landscape diversity index in 560 mapping grid squares with grid size approximately 130?km². Spatial correlations and regressions were established between human population density, appropriation of net primary production, land cover and biodiversity. We found positive spatial coincidence between human population density and species richness. Although the amount of net primary production was not related to species richness in general, we found significant negative spatial relationship between ecosystem use intensity and landscape diversity. As the area of the Czech Republic exhibits relatively high land use intensities, spatial patterns of human impacts have important implications for land management and biodiversity conservation in a cultural landscape.     

Relationships between the damage to radish caused by the root-lesion nematode Pratylenchus penetrans, its density prior to cultivation and the soil nematode community structure evaluated by polymerase chain reaction-denaturing gradient gel electrophoresis

A preliminary survey using 20 conventionally farmed fields in which fumigants have been applied every year showed that the root-lesion nematode Pratylenchus penetrans was distributed both in the upper (0–30 cm) and lower (30–60 cm) soil layers. In six of the 20 fields, P. penetrans was detected in the lower layers exclusively, suggesting that the most appropriate depth to sample soil is 0–60 cm to estimate the relationship between the density of P. penetrans and its damage to radish. There was a highly significant correlation ( r  = 0.923) between the density of P. penetrans in the 0–60 cm depth and the number of spots on a radish. No damage to radish was observed in soils with <2.5 individuals of P. penetrans per 20 g soil before cultivation. However, in cases in which the density of P. penetrans was 3.4–6.2 individuals per 20 g soil, the number of spots on a radish showed more variation (0–131.5 per radish) and there was no significant correlation between them. The nematode community structure of soils with 3.4–8 individuals of P. penetrans per 20 g soil, evaluated by polymerase chain reaction-denaturing gradient gel electrophoresis, was significantly different ( anova , PC2, P  <   0.05) between soils with low (0–42) and high (more than 80) damage levels, suggesting that radish damage might be predicted on the basis of the prevailing soil nematode community structure.     

Metabolism of curcuminoids in tissue slices and subcellular fractions from rat liver

Curcumin and its natural congeners are of current interest because of their putative anti-inflammatory and anticarcinogenic activities, but knowledge about their metabolic fate is scant. In the present study conducted with precision-cut liver slices from male and female Sprague-Dawley rats, five reductive but no oxidative metabolites of curcumin and its demethoxy and bis-demethoxy analogues were observed and identified by HPLC and GC-MS analysis, mostly by comparison with authentic reference compounds. The major reductive metabolites were the hexahydrocurcuminoids in both male and female rat liver slices, whereas male rats formed more octahydro than tetrahydro metabolites and female rats more tetrahydro- than octahydrocurcuminoids. Tetrahydro, hexahydro, and octahydro metabolites were predominantly present as glucuronides, but a significant proportion of sulfate conjugates was also observed. The lack of formation of oxidative metabolites of curcumin and the ready generation of reductive metabolites were confirmed using rat liver microsomes and cytosol, respectively. Results of enzymatic hydrolysis studies conducted under various conditions revealed that curcumin and demethoxycurcumin are chemically less stable than bis-demethoxycurcumin, whereas the reductive metabolites of all three curcuminoids are stable compounds. This is the first report on the metabolism of demethoxycurcumin and bis-demethoxycurcumin. In view of the chemical instability of the parent curcuminoids, it is proposed to use their major phase I metabolites, that is, the stable hexahydro products, as biomarkers for exposure in clinical studies.     

Quantitative variations in the essential oil of Minthostachys mollis (Kunth.) Griseb. in response to insects with different feeding habits

Plants display a diverse array of inducible changes in secondary metabolites following insect herbivory. Herbivores differ in their feeding behavior, physiology, and mode of attachment to the leaf surface, and such variations might be reflected in the induced responses of damaged plants. Induced changes were analyzed for Minthostachys mollis, a Lamiaceae with medicinal and aromatic uses, and four species of folivore insects with different feeding habits (chewing, scraping, sap-sucking, and puncturing). In M. mollis leaves experimentally exposed to the insects, levels of the two dominant monoterpenes pulegone and menthone were assessed 24 and 48 h after wounding. Menthone content generally decreased in the essential oil of damaged leaves, whereas pulegone concentration increased in all treatments. These changes occurred also in the adjacent undamaged leaves, suggesting a systemic response. The relatively uniform response to different kinds of damage could be attributable to the presence of such a strongly active compound as pulegone in the essential oil of M. mollis. The effects of wounding on essential oil concentration may be significant from a commercial point of view.     

Heavy Metal Behaviour in an Experimental Free Water Surface Wetland in the Venice Lagoon Watershed

Wetlands are effective in the treatment of polluted surface water. A semi-natural wetland pilot plant was established to verify the pollutant abatement effectiveness of the Venice Lagoon inlet water. The unique conditions of this brackish environmental site are: (1) a high concentration of carbonate and low concentrations of sulphides, and (2) the abundance of organic matter in sediments. The goal of this study was to examine how these characteristics influence the metal mobility in the wetland and to compare our results to published literature. The data collected were limited with respect to statistical analysis because the metal concentrations were often below the detection limits. Therefore, we chose to perform non-parametric analyses. To analyse the relationships among heavy metal concentrations and the physical and chemical wetland variables, and to investigate the processes of metal removal, we performed a multivariate statistical analysis and a Spearman correlation analysis. The results indicated that the reduced and basic conditions of the sediments seen in the Venice Lagoon environment facilitated the removal of metals due to the formation of insoluble compounds with sulphides and carbonates.     

Effects of Magnesium Deficiency on Carbohydrates in Phaseolus vulgaris

Phaseolus vulgaris ‘Saxa’ was cultivated in quartz sand under natural light conditions in an open-top-chamber and supplied with either complete (1.3 mM Mg) or magnesium-free nutrient solution. 57 days old plants showed interveinal chloroses of older leaves, decreased magnesium and increased potassium tissue concentrations in leaves and pods. Plants with magnesium supply exhibited typical diurnal changes of hexoses, sucrose and starch in trifoliate leaves. Magnesium deficiency caused retarded sucrose formation and pronounced starch accumulation in trifoliate leaves throughout the day. Soluble sugars and starch were decreased in pods of plants without Mg-supply. The results are discussed with regard to diurnal changes of carbohydrate metabolism.     

The effect of organic matter on the structure of soils of different land uses

In this study, the soil structure of two soils (Haplic Chernozem and Eutric Fluvisol) of different land uses (forest, meadow, urban and agro-ecosystem – consisted of four crop rotations) in Slovakia was compared. The soil aggregate stability was determined with a dependence on the chemical composition of plant residues. The quantity and quality of the organic matter was assessed through the parameters of the C and N in size fractions of dry-sieved and water-resistant aggregates. The soil structure of the forest ecosystem was evaluated as the best of all of forms of land use. Differences in the soil structure under the grass vegetation of a meadow (natural conditions) and urban ecosystem were also recorded. The agro-ecosystem was characterised by a higher portion (55.95%) of the most valuable (agronomically) water-resistant aggregate size fraction of 0.5–3 mm. Values of the carbon management index showed that the larger water-resistant aggregates were, the greater were the changes in the organic matter (r = ?0.680, P < 0.05). In addition, a smaller content of dry-sieved aggregates of the 3–5 mm size fraction was observed with higher contents of soil organic carbon (SOC) (r = ?0.728, P < 0.05) and labile carbon (C_L) (r = ?0.760, P < 0.05); there were also greater changes in the soil organic matter and vice versa, higher contents of SOC (r = 0.744, P < 0.05) and C_L (r = 0.806, P < 0.05) greater contents of dry-sieved aggregates of size fraction 0.5–1 mm. The soil structure of agro-ecosystem was superior at a higher content of cellulose (r = ?0.712, P < 0.05) in the plant residues. The higher content of cellulose and hemicellulose in the plant residue of a previous crop was reflected in a smaller C_L content in the water-resistant aggregates (r = ?0.984, P < 0.05). A correlation was observed between a high content of lignin in the plant residue and a smaller SOC content in the water-resistant aggregates (r = ?0.967, P < 0.05). Lastly, a higher content of proteins in the plant residues (r = 0.744, P < 0.05) supported a greater content of dry-sieved aggregates of the 0.5–1 mm size fraction.     

Cyclic estrous-like behavior in a spayed cat associated with excessive sex-hormone production by an adrenocortical carcinoma

A 15-year-old, spayed female domestic shorthair cat was evaluated for 1-year duration of cyclic intermittent estrous behavior. Diagnostic testing performed before referral, including baseline progesterone concentration, human chorionic gonadotropin (hCG) hormone stimulation test and surgical exploratory laparotomy, had remained inconclusive for a remnant ovary. Evaluation of sex hormones before and after adrenocorticotropic hormone (ACTH) administration revealed increased basal concentrations of androstenedione, estradiol, progesterone, and 17α-hydroxyprogesterone and normal ACTH-stimulated hormone concentrations. Enlargement of the right adrenal gland was identified by abdominal ultrasound. The cat underwent an adrenalectomy and histopathology of the excised adrenal gland was consistent with an adrenocortical carcinoma. Clinical signs resolved immediately following surgery, and most hormone concentrations declined to within or below the reference interval (RI) by 2 months after surgery.