Digestibility,fecal characteristics,and plasma glucose and urea in dogs fed a commercial dog food once or three times daily

Digestibility, fecal characteristics, and levels of glucose and urea in the plasma were determined in 8 dogs that received 2 different dog foods once or 3 times daily. One dog food (A) was 5 times more expensive than the other (B). Fecal pH and consistency, digestibility of dry matter (DM), organic matter (OM), crude protein (CP), and crude fiber (CF) were determined. Blood samples were taken from 30 min before to 60 min after a meal. Digestibilities of DM, OM, and CP, and fecal consistency were higher, and daily fecal excretion and fecal pH were lower when dogs were fed food A (P < 0.001). The feeding schedule had no effect on plasma glucose and urea. Neither feeding frequency nor food × frequency interactions was significant for the parameters studied.     

Vole pests in apple orchards: use of presence signs to estimate the abundance of Arvicola terrestris cantabriae and Microtus lusitanicus

The sustainable management of vole populations to reduce crop damage requires a reliable estimation of rodent density. The present study was conducted in 2011 in Asturias (NW, Spain) and aimed at developing a method for estimating the density of the water vole Arvicola terrestris cantabriae and the Lusitanian pine vole Microtus lusitanicus in apple orchards based on their presence signs. Previously, as A. t. cantabriae and the Iberian mole Talpa occidentalis occur simultaneously in the same habitats, we had to determine if earth mounds caused by these two species may be accurately differentiated. The results showed that presence signs may be used to discriminate the occurrence of A. t. cantabriae and T. occidentalis in areas of sympatry. The characteristics most interesting for species differentiation were the linear distribution pattern of the mounds and the occurrence of ‘earth sausages’ and ‘earth paths’, all of them typical of moles. The high correlation coefficients (r _s ?>?0.88) obtained between animal captures and the presence of activity signs for the two vole species revealed that it is possible to estimate A. t. cantabriae and M. lusitanicus densities by using the presence signs. An estimating model adapted for apple orchards and for simultaneous sampling both voles is proposed. In addition, we confirmed that the three mammal species coexist frequently in the same orchards. The negative relation between A. t. cantabriae and M. lusitanicus numbers suggests a competitive displacement between species. The results of the present study have valuable applications for both crop protection and research purposes.     

Cryptosporidium species detected in calves and cattle in Dagoretti, Nairobi, Kenya

A total of 1,734 cattle faecal samples from 296 dairy-keeping households were collected from urban settings in Nairobi, Kenya. Modified Ziehl-Neelsen staining method and an immunofluorescence assay were used to identify those samples with Cryptosporidium oocyst infection. Oocysts from positive faecal samples were isolated by Sheather's sucrose flotation method and picked from the concentrate using cover slips. Genomic DNA was extracted from 124 of the faecal samples that were positive for Cryptosporidium and was used as template for nested PCR of the 18S rRNA gene. Twenty-five samples (20?%) were PCR-positive for Cryptosporidium, and 24 of the PCR products were successfully cloned and sequenced. Sequence and phylogenetic analysis identified 17 samples (68?%) as Cryptosporidium parvum-like, four samples (16?%) as Cryptosporidium ryanae, three samples (12?%) as Cryptosporidium andersoni and one sample (4?%) as Cryptosporidium hominis. To the best of our knowledge, this is the first genotyping study to report C. parvum-like, C. andersoni and C. hominis in cattle from Kenya. The results of this study show Cryptosporidium infections in calves and cattle may be potential zoonotic reservoirs of the parasite that infects humans.     

Application of the CSM-CERES-Rice model for evaluation of plant density and nitrogen management of fine transplanted rice for an irrigated semiarid environment

The objectives of this study were to evaluate the performance of the cropping system model (CSM)-CERES-Rice to simulate growth and development of an aromatic rice variety under irrigated conditions in a semiarid environment of Pakistan and to determine the impact of various plant densities and nitrogen (N) application rates on grain yield and economic return. The crop simulation model was evaluated with experimental data collected in experiments that were conducted in 2000 and 2001 in Faisalabad, Punjab, Pakistan. The experimental design was a randomized complete block design with three replications and included three plant densities (one seedling hill⁻¹, PD₁; two seedlings hill⁻¹, PD₂; and three seedlings hill⁻¹, PD₃) and five N fertilizer regimes (control, N₀; 50 kg ha⁻¹, N₅₀; 100 kg ha⁻¹, N₁₀₀; 150 kg ha⁻¹, N₁₅₀; and 200 kg ha⁻¹, N₂₀₀). To determine the most appropriate combination of plant density and N levels, four plant densities from one seedling hill⁻¹ to four seedlings hill⁻¹ and 13 N levels ranging from 0 to 300 kg N ha⁻¹ (52 scenarios) were simulated for 35 years of historical daily weather data under irrigated conditions. The evaluation of CSM-CERES-Rice showed that the model was able to simulate growth and yield of irrigated rice in the semiarid conditions, with an average error of 11% between simulated and observed grain yield. The results of the stimulation analysis result showed that two seedlings hill⁻¹ along with 200 kg N ha⁻¹ (PD₂N₂₀₀) produced the highest yield as compared to all other scenarios. Furthermore, the economic analysis through the mean gini dominance also showed the dominance of this treatment (PD₂N₂₀₀) compared to the other treatment combinations. Thus, the management scenario that consisted of two seedlings hill⁻¹ and 200 kg N ha⁻¹ was the best for high yield and monitory return of irrigated rice in the semiarid environment. The mean monetary returns ranged from 291 US $ ha⁻¹ to 1 460 US $ ha⁻¹ to 1 460 US  ha⁻¹ among the 52 production options that were simulated. This approaching was demonstrated as effective way to optimize the density and N management for high yield and monetary return. It will help the rice production.     

Seedlings growth promotion by Azospirillum brasilense under normal and drought conditions remains unaltered in Tebuconazole-treated wheat seeds

The wide use of pesticides in modern agriculture may cause side effects on the non-target microflora. Data on the fungicide Tebuconazole effects on Azospirillum-wheat association are scarce. We analyzed the effects of Tebuconazole on: (a) Azospirillum brasilense Sp245 growth in pure culture, (b) A. brasilense Sp245 colonization of Triticum aestivum cv ProINTA Oasis roots, (c) A. brasilense Sp245-inoculated seedlings growth under normal and water stress conditions in the presence of 20% polyethylene glycol 8000. Seeds were separated in Tebuconazole-free and Tebuconazole-treated lots. Inoculated and non-inoculated seedlings were grown in hydroponics in the dark at 20 °C for 72 h. Root surface, coleoptile length, fresh and dry (DW) weights in both tissues and diazotrophic bacterial most probable number in roots were determined. Water contents and shoot-to-roots DW ratio were calculated. Neither Azospirillum growth nor root colonization was affected by Tebuconazole. Under normal growth conditions most of the growth parameters analyzed, revealed a clear positive effect of A. brasilense on wheat seedlings up to 72 h treatments. The characteristic Azospirillum enhancing effects observed on roots remained unaltered by Tebuconazole. The present study shows that Tebuconazole is compatible with A. brasilense Sp245-wheat inoculation.     

Screening chloroplast regions in <Emphasis Type="Italic">Calophyllum brasiliense</Emphasis> (Calophyllaceae) for suitability for population genetic analyses

The uniparental inheritance and conserved structure of the chloroplast genome among many angiosperms makes it suitable for constructing gene lineages and inferring population histories based on these relationships. However, the analysis of a single chloroplast region to solve population issues has not yielded the desired amount of variability due to the low mutation rate. Therefore, it is necessary to screen and carefully analyze chloroplast intergenic or intronic regions to select the most appropriate for studying the genetic variability in the chloroplast genome of a particular taxon. In this context, the aim of this work was to characterize 8 regions in Calophyllum brasiliense using 11 selected primer pairs and to evaluate their usefulness for phylogeographic analysis. Intergenic spacers petA-psbJ, petG-trnP and rpl32-trnL and the trnL intron demonstrated potentially informative sites. The combination of these 4 regions will allow the analysis of genetic population structure and the integration of historical aspects to inform strategies for conserving C. brasiliense, especially for highly impacted populations and those at risk of local extinction.     

Characterization of rhizobia from <Emphasis Type="Italic">Sesbania</Emphasis> species native to seasonally wetland areas in Uruguay

Naturally growing Sesbania species with tolerance to unfavourable habitats are widely distributed in non-cultivated seasonally wetland areas in Uruguay. We investigated the relative abundance, diversity and symbiotic efficiency of Sesbania punicea and S. virgata rhizobia in three ecologically different undisturbed and water-logged sites in Uruguay. Numbers of native-soil rhizobia infective on S. punicea or S. virgata were low, with higher numbers associated with the presence of S. virgata. Plants of S. virgata inoculated with soil suspension showed aerial and nodule biomass greater than that obtained with S. punicea. The rhizobia nodulating Sesbania species in water-logged lands in different regions of Uruguay were diverse differing in growth rates, acid production, growth at 39°C and in LB medium, host range and symbiotic efficiency. Seventeen representative strains clustered into four groups on the basis of phenotypic characteristics, ARDRA and DNA fingerprinting (GTG₅-PCR). Partial sequence of 16S rRNA from eight of these strains classified them into at least two genera with four species: Azorhizobium doebereinerae, Rhizobium sp. related to R. etli and two different Rhizobium sp.-Agrobacterium. Our results confirm the presence of the specie Azorhizobium doebereinerae as microsymbionts of S. virgata in South America. No strain of Rhizobium etli has previously been reported as a microsymbiont of Sesbania, though R. etli like organisms have also been recovered from Dalea purpurea and Desmanthus illinoensis. Significant increases in dry matter production were obtained with S. virgata plants inoculated with selected rhizobial strains under growth chamber conditions.