Efecto de la suplementación sobre el peso del ternero y la preñez y condición corporal de vacas del Bajo Chaco Paraguayo

The objective of the study was to evaluate the effect of concentrate supplementation of suckling calves on their weight gain, as well as the pregnancy percentage and body condition of the cows, which was carried out in an establishment located in the Department of Presidente Hayes, Lower Paraguayan Chaco. Thirty unweaned calves from multiparous cows between 2 and 3 months of age, were used. They were grouped into two treatments (T) of 15 calves and 15 cows for each treatment (T1: calves not supplemented and T2: calves supplemented), which grazed on a native pasture during the assay. The supplement consisted of a concentrate with 20% crude protein and 3 Mcal/kg of metabolizable energy, which was offered for 120 days. On each T, a Brangus bull was assigned to service the cows for 70 days. The average daily weight gain of the calves was 0.464 and 0.708 kg for T1 and T2, respectively, the difference being statistically significant (p<0.05). On the other hand, the pregnancy percentage was identical in both groups (7%). However, the number of cows with the highest final body condition (FBC3) increased in T2. It can be concluded that the most important effect was the improvement in the daily weight gain of the calves that received the supplementation and the increase in the number of cows with FBC3.El objetivo del estudio fue evaluar el efecto de la suplementación de terneros lactantes sobre su ganancia de peso, así como el porcentaje de preñez y condición corporal de las vacas. La investigación fue realizada en un establecimiento ubicado en el Departamento Presidente Hayes, en el Bajo Chaco Paraguayo. Se utilizaron treinta terneros de 2 a 3 meses de edad, crías de vacas adultas multíparas, que se agruparon en dos tratamientos (T) de 15 terneros y 15 vacas por cada uno (T1: terneros no suplementados y T2: terneros suplementados, ambos pastando sobre una pradera nativa en forma continua). El suplemento utilizado fue un concentrado con 20% de proteína bruta y 3 Mcal/kg de energía metabolizable, que se ofertó durante 120 días. En cada T se asignó un toro tipo Brangus para el servicio de las vacas, por 70 días. La ganancia diaria promedio de peso de los terneros fue de 0,464 y 0,708 kg para T1 y T2 respectivamente, siendo la diferencia estadísticamente significativa (p<0,05); no así el porcentaje de preñez, que fue idéntico en ambos grupos (7%). Sin embargo, en T2 aumentó la cantidad de vacas con la condición corporal final más alta (CCF3), diferencia que fue estadísticamente significativa (p<0,05). Se concluye que los efectos más importantes fueron la mejoría en la ganancia diaria de peso de los terneros que recibieron la suplementación y el aumento de la cantidad de vacas con CCF3

Sustitución de ingredientes proteicos y su efecto sobre parámetros productivos en toros de Paraguay

In order to determine the effect of substituting protein ingredients on production parameters (daily weight gain, feed intake and feed conversion) in confined bulls, bovine animals were selected, grouped into 2 lots in a random and homogeneous manner, composed of nelore-type bulls between 1 and 3 years of age: Treatment 1 (T1) 51 bulls with feed based on corn mockery and Treatment 2 (T2) 51 bulls with feed based on soybean expeller. The initial weighing was carried out at the entrance of the animals, after which two weighings were carried out, one at 45 days and the other at 90 days. At the end of the period, the weights of each group were compared. The results obtained based on the daily weight gain were subjected to the T-Student statistical method, observing significant differences (p<0.05), in favor of T2 in relation to T1. Daily weight gain was 1.47 kg/day at T1, 1.52 kg/day at T2, with daily consumption at T1 being 16.8 kg and 17.4 kg at T2, in terms of feed conversion at T1 it was 6.75 kg and at T2 it was 6.82 kg.Con el objetivo de determinar el efecto de la sustitución de ingredientes proteicos sobre parámetros productivos en toros confinados (ganancia diaria de peso, consumo y conversión alimenticia), fueron seleccionados animales de la especie bovina, agrupados en 2 lotes de forma aleatoria y homogénea, compuestos por toros tipo nelore de entre 1 a 3 años de edad: Tratamiento 1 (T1) 51 toros con alimento a base de burlanda de maíz y Tratamiento 2 (T2) 51 toros con alimento a base de expeller de soja. El pesaje inicial se realizó a la entrada de los animales. Posterior a eso se procedió a dos pesajes, uno a los 45 días y otro a los 90 días. Al final del período se realizó la comparación de los pesos de cada grupo. Los resultados obtenidos en base a la ganancia diaria de peso fueron sometidos al método estadístico T-Student, observándose diferencias significativas (p<0,05) a favor del T2 en relación al T1. La ganancia diaria de peso fue en el T1 de 1,47 kg/día y en el T2 1,52 kg/día, siendo el consumo diario en el T1 de 16,8 kg y en el T2 17,4 kg. En cuanto a la conversión alimenticia en el T1 fue de 6,75 kg y en el T2 fue de 6,82 kg

Bayesian mapping for infectious bronchitis virus risk in backyard chickens in Paraguay

Poultry production is a developing industry in Paraguay, South America. The inadequate farm management methods commonly used in backyard chickens make them a potential reservoir for economically important diseases such as infectious bronchitis that can affect commercial poultry operations. There are no earlier studies on a survey of Infectious Bronchitis Virus (IBV) amongst backyard chicken population in Paraguay. The objectives of this study were: (1) to observe the seroprevalence of IBV in backyard chickens in Paraguay and (2) to generate maps for estimated seroprevalence using Bayesian techniques for IBV in the study chickens and for smoothed Relative Risks (RR) drawn by one of the techniques above, in place of using the observed seroprevalence. Paraguay consists of 17 departments. A department-stratified random sampling was designed and implemented. The required total sample size of 1537 from a chicken population of 17 million was adequate to produce a 95% confidence interval with a desired precision of ±2.5% when the estimated seroprevalence was 50%. Sera were analyzed using a commercial indirect ELISA. The overall observed antibody seroprevalence was 80%. The resulting maps for the estimated seroprevalence for IBV using Bayesian techniques in the study chickens at department level, and for the smoothed RRs were illustrated. Different types of epidemiological parameters can be computed to take account of potential risk factors. Therefore, further detailed studies into those risk factors associated with IBV appearance with respect to spatially epidemiological variations would be of interest.Facultad de Ciencias Veterinaria

Bayesian mapping for infectious bronchitis virus risk in backyard chickens in Paraguay

Poultry production is a developing industry in Paraguay, South America. The inadequate farm management methods commonly used in backyard chickens make them a potential reservoir for economically important diseases such as infectious bronchitis that can affect commercial poultry operations. There are no earlier studies on a survey of Infectious Bronchitis Virus (IBV) amongst backyard chicken population in Paraguay. The objectives of this study were: (1) to observe the seroprevalence of IBV in backyard chickens in Paraguay and (2) to generate maps for estimated seroprevalence using Bayesian techniques for IBV in the study chickens and for smoothed Relative Risks (RR) drawn by one of the techniques above, in place of using the observed seroprevalence. Paraguay consists of 17 departments. A department-stratified random sampling was designed and implemented. The required total sample size of 1537 from a chicken population of 17 million was adequate to produce a 95% confidence interval with a desired precision of ±2.5% when the estimated seroprevalence was 50%. Sera were analyzed using a commercial indirect ELISA. The overall observed antibody seroprevalence was 80%. The resulting maps for the estimated seroprevalence for IBV using Bayesian techniques in the study chickens at department level, and for the smoothed RRs were illustrated. Different types of epidemiological parameters can be computed to take account of potential risk factors. Therefore, further detailed studies into those risk factors associated with IBV appearance with respect to spatially epidemiological variations would be of interest.Facultad de Ciencias Veterinaria

Probability mapping for mycoplasma gallisepticum risk in backyard chickens in Paraguay

Poultry production is a growing industry in Paraguay, South America.The insufficient farm management methods commonly used in backyard chickens make them a potential reservoir for economically important diseases such as Mycoplasma gallisepticum that can influence commercial poultry operations.There are no previous studies on a survey of Mycoplasma gallisepticum among backyard chicken population in Paraguay.The objectives of this study were:(a) to determine the seroprevalence of Mycoplasma gallisepticum in backyard chickens in Paraguay and (b) to generate choropleth maps for the Standardized Risk Ratio (SRR) for Mycoplasma gallisepticum in the study chickens and Poison probabilities for the SRR, in place of using the raw seroprevalence.Paraguay is divided into 17 departments.A department-stratified random sampling was planned and conducted.The required total sample size of 1291 from a chicken population of 17 million was sufficient to produce a 95% confidence interval with a desired precision of ±.5% when the estimated antibody seroprevalence was 30%.Sera were analyzed using a commercial indirect ELISA.The observed overall seroprevalence was 26%.The resulting maps for the SRR for Mycoplasma gallisepticum in the study chickens at department level and Poison probabilities for the SRR were depicted.Departments with significantly high or low disease risks were confirmed.Different types of epidemiological parameters can be calculated to take account of potential risk factors.Therefore, further detailed investigations into those risk factors associated with Mycoplasma gallisepticum occurrence with respect to spatially epidemiological differences would be of interest.Facultad de Ciencias Veterinaria

Large scale shell model calculations for odd-odd 58−62^{58-62}Mn isotopes

Large scale shell model calculations have been carried out for odd-odd $^{58-62}$Mn isotopes in two different model spaces. First set of calculations have been carried out in full $\it{fp}$ shell valence space with two recently derived $\it{fp}$ shell interactions namely GXPF1A and KB3G treating $^{40}$Ca as core. The second set of calculations have been performed in ${fpg_{9/2}}$ valence space with the $fpg$ interaction treating $^{48}$Ca as core and imposing a truncation by allowing up to a total of six particle excitations from the 0f$_{7/2}$ orbital to the upper $\it{fp}$ orbitals for protons and from the upper $\it{fp}$ orbitals to the 0g$_{9/2}$ orbital for neutron. For low-lying states in $^{58}$Mn, the KB3G and GXPF1A both predicts good results and for $^{60}$Mn, KB3G is much better than GXPF1A. For negative parity and high-spin positive parity states in both isotopes $fpg$ interaction is required. Experimental data on $^{62}$Mn is sparse and therefore it is not possible to make any definite conclusions. More experimental data on negative parity states is needed to ascertain the importance of 0g$_{9/2}$ and higher orbitals in neutron rich Mn isotopes.Comment: 5 pages, 4 figures, Submitted to Eur. Phys. J.

Prevalencia de microorganismos y perfil de resistencia antimicrobiana en bovinos lecheros de Paraguay

The bovine mastitis is an inflammation of the mammary glands of endemic presentation mainly caused by the invasion of pathogenic microorganisms. The objective of the study was to identify the most frequently isolated microorganisms and to determine the antimicrobial resistance profile according to the species or group of species of microorganisms isolated. The 411 milk samples were taken from equal numbers of California Mastitis Test CMT-positive quarter cows from dairy breeds in 3 departments of Paraguay (224, 137 and 50 from the Central, Cordillera and Paraguarí departments), which were subjected to microbial species identification cultures. Microbial sensitivity to antimicrobials was evaluated by plate dilution. The absolute and relative frequency of microorganisms and resistances were quantified with the Epiinfo 7.0 software. The 37.4% of the microorganisms corresponded to Streptocccus sp, 35.3% to the coagulase negative Staphylococcus group (SCN) and 16.1% to the coagulase positive Staphylococcus (SCP) as the most frequent. The antimicrobial resistance profile in decreasing order was tetracycline, penicillin, sulfatrimoprim, rifampicin and ampicillin (34.7; 19.7; 14.4; 8.2 and 6.4%, respectively). Streptocccus sp were resistant to 7/10 (range 51.3 to 1.7%), SCN to 8/10 (range 29.7 to 2%), and SCP to 7/10 (range 44.7 to 2.1%), while enterobacteria were resistant to 7/20, mainly to ampicillin (4/5). Multiresistance was also observed, although in a small number. It was concluded that the most frequent groups of microorganisms were Streptocccus sp, followed by SCN and thirdly SCP. Antimicrobial resistance, from highest to lowest, was to tetracycline, penicillin and sulfatrimetoprim, being still rare multiresistance.La mastitis bovina es la inflamación de las glándulas mamarias, causada mayoritariamente por invasión de microorganismos patógenos. El objetivo del estudio fue identificar los microorganismos más frecuentemente aislados y determinar el perfil de resistencia antimicrobiana en función de las especies o grupo de especies de microorganismos aislados. Se tomaron 411 muestras de leche de igual números de vacas de cuartos positivos al California Mastitis Test (CMT), de razas lecheras de 3 departamentos de Paraguay (224, 137 y 50 muestras), que se sometieron a cultivos microbianos de identificación fenotípica de especies. La sensibilidad microbiana a antimicrobianos se evaluó por dilución en placa. Las frecuencias absoluta y relativa de microorganismos, así como las resistencias, se cuantificaron con el software Epiinfo 7.0. El 37,4% de los microorganismos correspondieron a Streptocccus sp, el 35,3% al grupo Staphylococcus coagulasa negativos (SCN) y el 16,1% a los Staphylococcus coagulasa positivos (SCP). En orden decreciente, los perfiles de resistencia antimicrobiana fueron: tetraciclina, penicilina, sulfatrimoprim, rifampicina y ampicilina (34,7; 19,7; 14,4; 8,2 y 6,4%, respectivamente). Los Streptocccus spp fueron resistentes a 7/10 (rango de 51,3 a 1,7%), los SCN a 8/10 (rango de 29,7 a 2%) y los SCP a 7/10 (rango de 44,7 a 2,1%), mientras que las enterobacterias fueron resistentes a 7/20, fundamentalmente a la ampicilina (4/5). También se observaron multiresistencias, aunque en un número pequeño. Se concluye que los grupos de microorganismos más frecuentes fueron los Streptocccus sp, seguidos de los SCN y en tercer lugar los SCP. Las resistencias antimicrobianas, de mayor a menor, fueron: tetraciclina, penicilina y sulfatrimetoprim, siendo todavía poco frecuente la multiresistencia

Molecular characterization of an aggregation-prone variant of alpha-synuclein used to model synucleinopathies

The misfolding and aggregation of alpha-synuclein (aSyn) are thought to be central events in synucleinopathies. The physiological function of aSyn has been related to vesicle binding and trafficking, but the precise molecular mechanisms leading to aSyn pathogenicity are still obscure. In cell models, aSyn does not readily aggregate, even upon overexpression. Therefore, cellular models that enable the study of aSyn aggregation are essential tools for our understanding of the molecular mechanisms that govern such processes. Here, we investigated the structural features of SynT, an artificial variant of aSyn that has been widely used as a model of aggregation in mammalian cell systems, since it is more prone to aggregation than aSyn. Using Nuclear Magnetic Resonance (NMR) spectroscopy we performed a detailed structural characterization of SynT through a systematic comparison with normal, unmodified aSyn. Interestingly, we found that the conformations adopted by SynT resemble those described for the unmodified protein, demonstrating the usefulness of SynT as a model for aSyn aggregation. However, subtle differences were observed at the N-terminal region involving transient intra and/or intermolecular interactions that are known to regulate aSyn aggregation. Importantly, our results indicate that disturbances in the N-terminal region of SynT, and the consequent decrease in membrane binding of the modified protein, might contribute to the observed aggregation behavior of aSyn, and validate the use of SynT, one of the few models of aSyn aggregation in cultured cells

Bayesian mapping for infectious bronchitis virus risk in backyard chickens in Paraguay

Poultry production is a developing industry in Paraguay, South America. The inadequate farm management methods commonly used in backyard chickens make them a potential reservoir for economically important diseases such as infectious bronchitis that can affect commercial poultry operations. There are no earlier studies on a survey of Infectious Bronchitis Virus (IBV) amongst backyard chicken population in Paraguay. The objectives of this study were: (1) to observe the seroprevalence of IBV in backyard chickens in Paraguay and (2) to generate maps for estimated seroprevalence using Bayesian techniques for IBV in the study chickens and for smoothed Relative Risks (RR) drawn by one of the techniques above, in place of using the observed seroprevalence. Paraguay consists of 17 departments. A department-stratified random sampling was designed and implemented. The required total sample size of 1537 from a chicken population of 17 million was adequate to produce a 95% confidence interval with a desired precision of ±2.5% when the estimated seroprevalence was 50%. Sera were analyzed using a commercial indirect ELISA. The overall observed antibody seroprevalence was 80%. The resulting maps for the estimated seroprevalence for IBV using Bayesian techniques in the study chickens at department level, and for the smoothed RRs were illustrated. Different types of epidemiological parameters can be computed to take account of potential risk factors. Therefore, further detailed studies into those risk factors associated with IBV appearance with respect to spatially epidemiological variations would be of interest.Facultad de Ciencias Veterinaria

In vitro validation of biomedical polyester-based scaffolds: Poly(lactide-co-glycolide) as model-case

Monitoring and understanding the in vitro behaviour of polyester based scaffolds both comprising the study of the hydrolytic degradation and the cell seeding viability is essential to ensure the desired functionality, according to a given biomedical purpose. As a model case to compare the performance of techniques to monitor the in vitro behaviour, poly(lactide-co-glycolide) (PLGA) scaffolds were chosen. The in vitro hydrolytic degradation of PLGA scaffolds was carried out in water and phosphate buffered saline (PBS). The evolution of the mass loss, the molar mass, the thermal properties and the surface morphology were monitored. The hydrolytic degradation media was correspondingly evaluated by means of the study of the pH, the amount of acid released and the conductivity. In addition, the in vitro biocompatibility regarding the cell culture viability was studied under physiological conditions. The cellular adhesion, cellular ability to proliferate on the scaffold, the scaffold inflammatory profile and the effect of the scaffold degradation compounds on the cells were assessed. A comparative analysis of the exploited techniques in terms of promptness of identification, depth of knowledge, simplicity of obtaining results and cost of the technique was implemented. The results showed that, depending on the balance between the interest in ascertaining the trigger of degradation or deep into the knowledge of the causes and effects of cell culture viability, an appropriate plan of analysis of the validation of polyester-based scaffolds could be designed