Milk yield persistency in Brazilian Gyr cattle based on a random regression model

With the objective of evaluating measures of milk yield persistency, 27,000 test-day milk yield records from 3362 first lactations of Brazilian Gyr cows that calved between 1990 and 2007 were analyzed with a random regression model. Random, additive genetic and permanent environmental effects were modeled using Legendre polynomials of order 4 and 5, respectively. Residual variance was modeled using five classes. The average lactation curve was modeled using a fourth-order Legendre polynomial. Heritability estimates for measures of persistency ranged from 0.10 to 0.25. Genetic correlations between measures of persistency and 305-day milk yield (Y305) ranged from -0.52 to 0.03. At high selection intensities for persistency measures and Y305, few animals were selected in common. As the selection intensity for the two traits decreased, a higher percentage of animals were selected in common. The average predicted breeding values for Y305 according to year of birth of the cows had a substantial annual genetic gain. In contrast, no improvement in the average persistency breeding value was observed. We conclude that selection for total milk yield during lactation does not identify bulls or cows that are genetically superior in terms of milk yield persistency. A measure of persistency represented by the sum of deviations of estimated breeding value for days 31 to 280 in relation to estimated breeding value for day 30 should be preferred in genetic evaluations of this trait in the Gyr breed, since this measure showed a medium heritability and a genetic correlation with 305-day milk yield close to zero. In addition, this measure is more adequate at the time of peak lactation, which occurs between days 25 and 30 after calving in this breed.     

Molecular characterization of Corynebacterium pseudotuberculosis isolated from goats using ERIC-PCR

Corynebacterium pseudotuberculosis, the infectious agent of caseous lymphadenitis (CLA), is responsible for substantial economic losses in goat and sheep production. Molecular characterization of C. pseudotuberculosis isolates by enterobacterial repetitive intergenic consensus (ERIC)-PCR has shown promising results in genotyping strains isolated from sheep with CLA. We evaluated the genetic diversity of C. pseudotuberculosis isolates collected from the Sert?o region of the Pernambuco (PE) State, Brazil, and investigated the potential of ERIC-PCR as a tool for the molecular typing of strains of C. pseudotuberculosis isolated from goats. Thirty-two C. pseudotuberculosis strains isolated from goats in the municipalities of Floresta and Ibimirim, PE, C. pseudotuberculosis type strain ATCC 19410, the 1002 vaccine strain, and a field isolate of Rhodococcus equi were fingerprinted using the primers ERIC-1R and ERIC-2 and the primer pair ERIC- 1R+ERIC-2. Using 100% similarity as the cutoff, 8, 10, and 7 genotypes were obtained with ERIC-1-PCR, ERIC-2-PCR, and ERIC-1+2-PCR, respectively. The Hunter-Gaston discriminatory index calculated for the ERIC-1-PCR was 0.75. The index for the ERIC-2-PCR was 0.88, and the index for the ERIC-1+2-PCR was 0.79. Among goat isolates of C. pseudotuberculosis, three, two and four genotypes (found by ERIC-1-PCR, ERIC-2-PCR, and ERIC-1+2-PCR, respectively) had been previously described among sheep isolates from Minas Gerais State, Brazil. These results showed that ERIC-PCR has good discriminatory power and typeability, making it a useful tool for discrimination among C. pseudotuberculosis isolates from goats.     

Simultaneous determination of sulfamethoxazole and trimethoprim in biological fluids for high-throughput analysis: comparison of HPLC with ultraviolet and tandem mass spectrometric detection

The comparison of two methods based on online solid phase extraction-liquid chromatography with UV (SPE-LC-UV) or mass spectrometry detection (SPE-LC-MS/MS) for the simultaneous quantification of sulfamethoxazole (SMZ) and trimethoprim (TMP) is presented. The methods were validated and proved to be accurate. The analysis of standard samples for SMZ at concentrations of 0.5, 1.5, 25 and 50microg/mL demonstrated a relative standard deviation of less than 6% for both methods (n=18), while TMP samples at concentrations of 0.05, 0.15, 1.5 and 5.0microg/mL were analyzed with R.S.D. of less than 4% (n=18). The method with mass spectrometric detection was approximately six times more sensitive than the method with ultraviolet detection. The total run time for the SPE-LC-MS/MS was 2.5min per sample as opposed to 18.0min for the SPE-LC-UV method. The method with MS detection in comparison with UV detection proved to be more rugged and was successfully applied to pharmacokinetics studies.     

Protein identification pipeline for the homology-driven proteomics

Homology-driven proteomics is a major tool to characterize proteomes of organisms with unsequenced genomes. This paper addresses practical aspects of automated homology-driven protein identifications by LC-MS/MS on a hybrid LTQ Orbitrap mass spectrometer. All essential software elements supporting the presented pipeline are either hosted at the publicly accessible web server, or are available for free download.     

A novel and efficient and low-cost methodology for purification of Macrotyloma axillare (Leguminosae) seed lectin

The N-acetyl-galactosamine specific lectin from Macrotyloma axillare seeds (LMA) was purified by precipitation and ion exchange chromatography. The LMA 0.2 mol L(-1) fraction showed hemagglutinating activity on erythrocytes A1. The results for molecular mass determinations were about 28 kDa. The LMA pH-dependent assays showed best hemagglutinating activity at pH 6.0-8.0; being decreased at acidic/alkaline conditions and by EDTA treatment. LMA is a tetramer at pH 8.2 and a dimer at pH 4.0. Human erythrocytes from ABO system confirmed the A1 specificity for LMA. This new methodology is useful and easy, with low costs, for lectin purification in large amounts.     

Toward Quantifying the Relative Importance of Invertebrate Consumption and Bioturbation in Puerto Rican Streams

Although many tropical stream consumers have large effects on resource quantity and quality, little is known about the relative importance of consumption versus bioturbation. We quantified egestion rates of freshwater shrimps ( Atya spp. and Xiphocaris elongata ) and mayflies (Leptophlebiidae) in two forest streams within the Luquillo Experimental Forest, Puerto Rico. Consumer body size was a strong predictor of egestion rates, with mass-specific egestion rates declining with body size and per-individual egestion rates increasing with body size. We used these egestion rates, together with published rates of epilithon removal by consumers and epilithon accrual by particle deposition and periphytic growth ( i.e. , with and without consumer access), to estimate the importance of consumption and bioturbation after storm events and during base-flow conditions. Our estimates suggest that direct consumption of epilithon can only account for a minor proportion (< 5%) of material removed following storm events, with most removal likely resulting from bioturbation. During base-flow conditions, we found that consumers (largely shrimps) may be capable of consuming a significant proportion of the material that would otherwise accrue on benthic substrata, but this result was limited to one high-elevation site. Our study suggests that bioturbation is the dominant process that redistributes and entrains fine particles after storm events, and that a variable fraction of deposited and accrued benthic material may be consumed during base-flow conditions. Our results underscore the importance of tropical stream animals in altering the benthic environment through both consumption and bioturbation, and suggest that consumer-mediated material cycling is likely to be context dependent.     

Nonlinearity and fractality in the variability of cardiac period in the lizard, Gallotia galloti: effects of autonomic blockade

Both nonlinear and fractal properties of beat-to-beat R-R interval variability signal (RRV) of freely moving lizards (Gallotia galloti) were studied in baseline and under autonomic nervous system blockade. Nonlinear techniques allowed us to study the complexity, chaotic behavior, nonlinearity, stationarity, and regularity over time of RRV. Scaling behavior of RRV was studied by means of fractal techniques. The autonomic nervous system blockers used were atropine, propranolol, prazosin, and yohimbine. The nature of RRV was linear in baseline and under beta-, alpha(1)- and alpha(2)-adrenoceptor blockades. Atropine changed the linear nature of RRV to nonlinear and increased its stationarity, regularity and fractality. Propranolol increased the complexity and chaotic behavior, and decreased the stationarity, regularity, and fractality of RRV. Both prazosin and yohimbine did not change any of the nonlinear and fractal properties of RRV. It is suggested that 1) the use of both nonlinear and fractal analysis is an appropriate approach for studying cardiac period variability in reptiles; 2) the cholinergic activity, which seems to make the alpha(1)-, alpha(2)- and beta-adrenergic activity interaction unnecessary, determines the linear behavior in basal RRV; 3) fractality, as well as both RRV regularity and stationarity over time, may result from the balance between cholinergic and beta-adrenergic activities opposing actions; 4) beta-adrenergic activity may buffer both the complexity and chaotic behavior of RRV, and 5) neither the alpha(1)- nor the alpha(2)-adrenergic activity seem to be involved in the mediation of either nonlinear or fractal components of RRV.     

Reptiles used in traditional folk medicine: conservation implications

The present work provides an overview of the global use of reptiles in traditional folk medicine and the implications for conservation. The results demonstrate that at least 165 reptile species belonging to 104 genera and 30 families are used in traditional folk medicine around the world. Some species are used as sources of drugs for modern medical science. Of the reptiles recorded, 53% are included on lists of endangered species, demonstrating the importance of understanding such medicinal uses in the context of reptile conservation as well as the need for considering socio-cultural factors when establishing management plans directed towards the sustainable use of these reptiles.     

Synthesis, characterization and kinetic studies of the cis-[RuCl2(cyclen)] complex

We report here the synthesis, characterization and kinetic studies of cis-[RuCl₂(cyclen)]⁺ in aqueous solution, where cyclen is the macrocyclic ligand 1,4,7,10-tetraazacyclododecane. The complex releases one Cl⁻ producing cis-[RuCl(OH)(cyclen)]⁺ in aqueous solution at pH 4.60. The product of this reaction was characterized by Ultraviolet-Visible (UV-Vis) spectrum in comparison to the synthesized cis-[RuCl(OH)(cyclen)](BF₄)·2H₂O. The electrochemical data showed that E_pc of the Ru(III/II) peak increases as the macrocycle ring size decreases and also when the trans conformation is changed to cis. The chloride affinity of Ru(III) depends on the macrocycle ring size since cis-[RuCl₂(cyclam)]⁺ (cyclam=1,4,8,11-tetraazacyclotetradecane) does not release chloride for at least 12 h. The overall effect between cyclam and cyclen reflects the fact that the electron involved in the reduction enters a nonbonding π-d orbital and its energy is affected by the macrocyclic ligand.