Net mineral requirements for growth of Saanen goat kids in early life are similar among genders

The current mineral requirements for growing goat kids are based on sheep and cattle studies without differentiating between the stages of development or gender. The aims of this study were to determine the net requirements for growth of Ca, P, Mg, Na and K of Saanen goat kids during the initial stages of growth and to analyse the effect of gender on the net requirements for growth of these macrominerals. Eighteen female, 19 intact male and 10 castrated male Saanen goat kids were studied. The kids were selected applying a completely randomized design and slaughtered when their body weight (BW) reached approximately 5, 10 and 15 kg to determine the mineral requirements for growth at these stages. The net mineral requirements for growth were similar among genders. The goat kids had slightly increased net requirements of Ca, P and Mg for growth with increasing BW from 5 to 15 kg. The net requirements for growth of Ca, P, Mg, Na and K ranged from 9.61 to 9.67 g/kg of BW gain, 7.14 to 7.56 g/kg of BW gain, 0.34 to 0.37 g/kg of BW gain, 1.26 to 1.13 g/kg of BW gain, 1.88 to 1.82 g/kg of BW gain as the animals grew from 5 to 15 kg respectively. In conclusion, when formulating diets for Saanen goat kids in early growth stage mineral levels do not need to adjusted based on gender.     

Novel derivatives of ent-17,19-dihydroxy-16betaH-kaurane obtained by biotransformation with Verticillium lecanii

In the search for new routes in the synthesis of hydroxylated kaurane diterpenoids, Verticillium lecanii, grown in a mineral liquid medium for 48 h, was fed with ent-17,19-dihydroxy-16betaH-kaurane, obtained by hydroboration/oxidation of kaurenoic acid, a natural product easily isolated from plants of the genera Xylopia (Annonaceae) and Wedelia (Asteraceae). After 14 days, the culture medium was extracted with ethyl acetate, and the metabolites were purified by column chromatography on silica gel. The results show that V. lecanii biotransformed the starting material into three novel compounds: ent-11alpha,17,19-trihydroxy-16betaH-kaurane; ent-7alpha,17,19-trihydroxy-16betaH-kaurane; and ent-7beta,17,19-trihydroxy-16betaH-kaurane, the structures of which were fully elucidated by using classical and modern two-dimensional NMR techniques.     

An automatic flow procedure for the determination of 3-hydroxybutyrate in animal serum and plasma

An automatic flow procedure based on the multicommutation concept, comprising three-way solenoid valves, for the spectrophotometric determination of 3-hydroxybutyrate in animal serum and plasma is proposed. The 3-hydroxybutyrate was enzymatically converted to acetoacetate with the reduction of NAD+ to NADH monitored at 340 nm. It was possible to carry out up to 600 determinations without a significant decrease in the analytical signal, with 5 mg of 3-hydroxybutyrate dehydrogenase immobilized on porous silica beads and packed in a column. The system enabled 60 determinations/h of 3-hydroxybutyrate in the range of 10-150 mg L(-1), with a consumption of 0.9 mg of NAD+ and 200 microL of sample per determination. A detection limit of 2 mg L(-1) for both animal serum and plasma and coefficients of variation of 1.4% and 1.2% (n = 17), respectively, were determined. Animal serum and plasma samples were analyzed without previous treatment, the results of which agreed with those obtained using the conventional method (UV kit, Sigma).     

Surface Water Quality Assessment of Lis River Using Multivariate Statistical Methods

This study presents the application of multivariate statistical tools for the evaluation of spatial variations and the interpretation of water quality data obtained in a monitoring program of Lis river basin surface water, Portugal. Twenty-seven physicochemical and microbiological parameters were determined in six water sampling campaigns at 16 monitoring sites during the period from September 2003 to November 2006. Correlation analysis, principal component analysis, and cluster analysis were performed to evaluate the main water pollution sources and to characterize the spatial distribution of water pollution profiles in river basin. The results achieved with the statistical methodologies led to distinguish natural and anthropogenic pollution sources. Additionally, monitoring sites with similar water pollution profile were identified, indicating that some monitoring locations can be changed to improve the spatial characterization of water quality in the river basin. CBO, CQO, P, and N were identified as significant variables affecting spatial variations, namely in the Lis river middle reach. Besides the identification of main pollution sources, the applied statistical tools were able to identify spatial patterns of water pollution in Lis river basin, which further helps in the reassessment of the number and location of monitoring sites.     

Inorganic Parameters as Water Quality Indicators in Acidic Groundwater in a Tropical Region – Brasilia-DF (Brazil)

In Brazilian Tropical Cerrado Region, reactions related to parental-material breakdown and oxisols genesis strongly affect the groundwater chemical characteristics. These reactions are responsible for the low water pH values, the soil charge balance, and the re-equilibrium of dissolved inorganic carbon species. Brasilia, the capital of Brazil, lies in the Distrito Federal, in the central part of the Brazilian Cerrado Region and has been experiencing an intense urban development during the last 15 years. Many town-house complexes have been built without proper water supply or wastewater disposal conditions. In this work, we discuss the adequacy of traditional ground waters geochemical classification models applied to the most exploited aquifers in DF. Forty groundwater samples were collected and pH, conductivity and total dissolved solids were determined in the field. Na, K, Ca, Mg, Fe, Al, Cu, Cd, Cr Mn e Zn were determined by Inductively Coupled Plasma Atomic Emission Spectrometry and Atomic Absorption Spectrophotometry. We identify inorganic indicators of human interference on the quality of these waters and also suggest a new mean of interpretation of dissolved inorganic elements based on statistic treatment of multivariate data. It is revealed a particular geochemical feature concerning to the alkali and the earth alkali metals concentrations, and a typical trace-element behaviour, closely related to the human activities and to the geological-bearing material characteristics. For all of the samples supposed to be altered by any kind of human activity, the physico-chemical parameters were lower than the standards established by the water quality legal system.     

Water Remediation Using Calcium Phosphate Derived From Marine Residues

The processing of natural resources in marine and freshwater ecosystems, directly operated by industries related to maritime sector, contributes annually to several million tons of waste. The reuse and economic recovery of this waste would be very desirable and profitable, either economically or environmentally. In this work, the remediation of hazardous divalent metal ions from aqueous solutions using biological apatites derived from marine residues was addressed. The biological apatite (calcium phosphate particles) was produced by heat treatment of fish bones. Experimental sorption studies of kinetics and equilibrium of the metal ions as well as an evaluation of competitive sorption behavior for lead immobilization were carried out in batch operation mode. The efficiency and mechanisms of lead sorption on two different particle sizes of calcium phosphate from aqueous solution were investigated. The results showed a high adsorption capacity of the biosorbent for Pb²⁺ (above 370 mg/g_ads.), in opposition to Cd²⁺ and Zn²⁺. For the case of low initial concentrations of the metal ion, reducing the biosorbent particles size increases the sorption rate. It was possible to verify that lead immobilization proceeds with a rapid surface complexation of the lead on the sorption sites before partial dissolution of calcium phosphate and formation of pyromorphite-like compounds. By the selectivity experiments, performed using binary systems—Pb/Cd and Pb/Zn—it was evidenced a competitive process between the divalent ions, which leads to a considerable decrease on the adsorption capacity of the adsorbent material for all the metals.     

Analyzing soil-available phosphorus by the Mehlich-3 extraction method to recommend a phosphorus fertilizer application rate for maize production in northern Mozambique

ABSTRACT

The available phosphorus (P) in soil is a major limiting factor for maize productivity in the Nacala corridor, Mozambique. In this study, soils were collected from three representative sites, Ribaue, Nampula, and Nacala, in the area, and each was used for maize pot experiment with five P fertilizer levels. The soil-available P content was determined by the Mehlich-3 method at 30 days after P fertilization. The shoot biomass and P concentration at the tasseling stage increased as the P fertilizer level increased and were significantly expressed as a function of soil-available P. Based on the function, the available P that attains 90% of the maximum shoot biomass was estimated as 79 mg P₂O₅ kg^?1. Consequently, the results in this study suggest a recommendation of 32–74 kg P₂O₅ ha^?1 fertilizer for maize production in the Nacala corridor although a field evaluation and economical evaluation are necessary.     

Influence of porosity of low-density polyethylene media on the maturation process of biofilters used in recirculating aquaculture systems

The effect of pores with different diameters in polyethylene media on the process of ammonia nitrification during the maturation of biofilters is evaluated. Four types of media were produced: M1 without pores, M2 with 40–112 μm in diameter pores, M3 with 125–187 μm diameter pores, and M4 with 312–437 μm diameter pores. Ammonia concentrations were statistically equal among media. On the majority of days, nitrite concentrations were lowest for M1 and M2, intermediate for M3, and highest for M4. Increased pore diameter favored the formation of biofilm in the interior, but the pores obtained in the expansion process were not interconnected, which may have caused low oxygenation of the water in the internal area. It was concluded that porosity did not reduce biofiltration time and did not increase the efficiency of nitrification of ammonia.     

Potentiometric flow injection determination of glycerol in distilled spirits.

A single-line flow injection system including a tubular periodate-selective electrode without inner reference solution is proposed for glycerol determination in distilled spirits, based on oxidation of this polyol by periodate. Interferences due to 5.0 mg L(-1) Cu, 5000 mg L(-1) sucrose, and 3000 mg L(-1) fructose plus glucose were investigated. The procedure is characterized by a linear response for 20-500 mg L(-1) glycerol (r > 0.9999, n = 7), a relative standard deviation of results of <0.03, and an analytical throughput of 30 determinations per hour. Accuracy was assessed by applying the procedure to distilled spirits of sugarcane and grape already analyzed by HPLC; in addition, recoveries within 96 and 120% were obtained.