Abstract This study evaluated the genetic (TG) and phenotypic (TF) trends for the peak yield (PP), milk yield (RL), and lactation persistency (P) traits of the Murciano-Granadina (MG) goat lactation curve obtained from 80,872 lactations of 85,404 goats (historical records from 1990-2012). The biomodelling of lactation curves allowed us to estimate the PP, RL, and P traits using the Spline model in the “R” software. The genetic values (VGs) were obtained using the univariate animal model with repeated observations, employing the MTDFREML package. The TG and TF were estimated via the least-squares regression of the average of VGs and known yield information according to the year of birth. While calculating the TG and TF, linear regression coefficients (b) were obtained, where the b values for PP, RL, and P were +0.00071, +0.00698; +0.00114, +0.01117; and +0.00002, -0.00076, respectively. The TG and TF for the PP and RL behaved similarly following an upward trend line with increasing and decreasing intervals. The TG for P showed seasonal variations while the TF followed a downward trend with more consistent points in its trajectory; supporting the idea that high yields are detrimental to the P. These results inform the breeders about the behavior of these traits and provide the basis for the incorporation of the lactation persistency as a selection criteria in the genetic program of the MG breed.

Resumen El objetivo fue evaluar las tendencias genéticas (TG) y fenotípicas (TF) para los caracteres de pico productivo (PP), rendimiento lechero (RL) y persistencia de la lactación (P) en la curva de lactación de la raza Murciano-Granadina (MG). Para ello se utilizaron 180,872 lactaciones, de 85,404 cabras (registros históricos de 1990-2012). Para la obtención de los caracteres de interés (PP, RL y P) se realizó la biomodelación de curvas de lactación mediante el modelo Spline usando el software “R”. Los valores genéticos (VG) se obtuvieron mediante modelo animal univariado con observaciones repetidas, empleándose el paquete MTDFREML. Las TG y TF se estimaron vía mínimos cuadrados en una regresión del promedio de los VG e información productiva conocida según el año de nacimiento. En el cálculo de las TG y TF se obtuvieron coeficientes de regresión lineal (b), donde los valores b para PP, RL y P fueron de +0.00071, +0.00698; +0.00114, +0.01117 y +0.00002, -0.00076; respectivamente. El trayecto de TG, TF de PP y RL se comportó de la misma manera siguiendo una línea de tendencia ascendente con presencia de intervalos de crecimiento y decrecimiento. La TG de P mostró un comportamiento estacional y la TF fue descendente con puntos más consistentes en su recorrido; reforzando la idea de que altas producciones van en detrimento de la P. Estos resultados permiten informar a los criadores del comportamiento de estos caracteres y considerar la incorporación de la persistencia de la lactación como criterio de selección en el programa genético de la raza.

ABSTRACT The excellence of modern broiler production is based on the genetic improvement of broiler strains for high growth rate and high egg production, associated with technological developments in nutrition, management, and health. Over the last decades, the clinical biochemistry of broilers has been studied to determine serum biochemical component values; however, there are still many knowledge gaps on factors that determine changes in these values. In this study, the serum lipid and protein profiles of 4-week-old male and female Cobb broiler breeders were evaluated. Blood samples were collected on a commercial farm located in the city of Uberlândia, MG, Brazil. The following parameters were evaluated: total protein, albumin, globulin, albumin to globulin ratio (A/V), uric acid, urea, cholesterol, and triglyceride levels using an automatic analyzer. The results showed sex-specific biochemical patterns for most blood parameters evaluated. Moreover, the obtained values were different from those obtained in many published studies with broilers and commercial layers, stressing the need to develop further studies with chickens of different ages.

As limitações do N no cultivo do milho relacionam-se ao fato de a eficiência da adubação nitrogenada no milho não ultrapassar os 50%, principalmente devido aos processos de perda por volatilização, desnitrificação ou lixiviação no solo. Nesse contexto, torna-se importante o desenvolvimento de cultivares eficientes no uso de N (EUN). Assim, o objetivo foi elaborar índices que permitissem a seleção acurada de genótipos de milho eficientes no uso de nitrogênio para as condições de alta e baixa disponibilidade desse nutriente. O experimento foi conduzido em casa de vegetação na Universidade Federal de Viçosa (20º45'14''S; 42º52'53''W) durante o mês de outubro de 2010. Foram avaliadas 39 combinações híbridas experimentais e 14 linhagens de milho divergentes para a eficiência no uso de N em duas condições de disponibilidade desse nutriente. Foram realizadas a análise de importância relativa dos caracteres estudados, estimada por meio do método dos componentes principais, a análise de fatores e a confecção dos índices de seleção. A seleção indireta e precoce para genótipos de milho tropical pode ser realizada por meio dos índices I AN = 0,022 MPS + 0,35 PASR + 0,35 CR AXI + 0,35 EUN, para ambientes de alta disponibilidade de nitrogênio, e I BN = -0,06 PSAR + 0,35 AS AXI + 0,35 CR AXI + 0,39 MPS, para condições de baixa disponibilidade de nitrogênio.

Nitrogen (N) limitation in maize crops is related to the fact that the efficiency of nitrogen fertilization in maize does not exceed 50%, primarily due to volatilization, denitrification and soil leaching. Therefore, the development of new nitrogen use efficient (NUE) cultivars is necessary. The aim of the present study was to develop indices for the accurate selection of NUE maize genotypes for use in conditions of both high and low N availability. The experiment was conducted in a greenhouse (20º45'14"S; 42º52'53"W) at the Federal University of Viçosa during October 2010. A total of 39 experimental hybrid combinations and 14 maize lines differing in NUE were evaluated under two N availability conditions. We determined the relative importance of the studied characters using principal component analysis, factor analysis and by developing efficient selection indices. We conclude that indirect and early selection of tropical maize genotypes can be performed using the indices I HN = 0.022 SDM + 0.35 RSDM + 0.35 RL A + 0.35 NUE for high N availability environments and I LN = -0.06 RSDM + 0.35 RSA A + 0.35 RL A + 0.39 SDM for low N availability environments.

Amifostine acid S2-(3-aminpropylamino) ethylphosphorothioate) a prodrug that on desfosforilization by the action of alkaline phosphatase, it produces cisteamine, which works as a free radical scavenger. Amifostine is used in presence of cisplatine, an agent that produces free radicals during its action. Amifostine could diminish the harm to normal cells that assimilate the prodrug selectively. Based on different doses took place an evaluation of the ability of amifostine to reduce the effect on lipid peroxidation and the antioxidative system in the renal tissue. The smallest dose was the more effective one resulting with the lower levels of products of lipid peroxidation, and antioxidant system. The suggested model allows evaluating the citoprotective effect of the amifostine ranging from the molecular to the tissue level.

La Amifostina ácido S-2-(3-aminopropilamino) etiolfósforotioico), prodroga que al desfosforilarse por la fosfatasa alcalina produce el WR1065 2-(3_aminopropilamino) etanotiol, actúa como atrapador de radicales libres (RL). Su empleo frente al cisplatino, agente que genera RL durante su acción, podría disminuir el daño a las células normales que captan selectivamente la prodroga. Se evaluó la capacidad de la amifostina a diferentes dosis sobre la peroxidación lipídica (TBARS) y la actividad de las enzimas antioxidantes superóxido dismutasa (SOD) y catalasa (CAT) en el tejido renal. Las dosis más efectivas fueron las más bajas, con las que se obtienen la menor concentración de TBARS y la menor actividad SOD y CAT. El modelo es una propuesta para evaluar el efecto citoprotector de la amifostina desde el nivel molecular al tisular.

Com esta pesquisa, objetivou-se estudar a viabilidade técnico-econômica da utilização da uréia comparando-se a ração-padrão e aquela contendo cama de frango, como suplemento ao feno de capim-elefante, para alimentação de ovinos da raça Santa Inês em confinamento. Para isso, ajustou-se uma função de produção a dados experimentais e determinou-se a máxima receita líquida (RL), o tempo ótimo de abate e o máximo período em que os animais podem ser confinados quando a RL será zero. Foram utilizados 40 ovinos, sendo 20 machos e 20 fêmeas confinados por 70 dias. O delineamento foi em blocos ao acaso, com cinco tratamentos e quatro repetições. Os tratamentos utilizados foram: I = 50% de feno + 50% de ração-padrão; II = 60% de feno + 40% de ração com cama de frango; III = 40% feno + 60% de ração com cama de frango; IV = 60% de feno + 40% de ração com uréia; e V = 40% de feno + 60% de ração com uréia. As dietas foram isoprotéicas e fornecidas ad libitum. A variável dependente usada nos ajustamentos foi o ganho de peso em confinamento (Y), e como variáveis explanatórias, período de tempo de 14 dias (T) e dummy, sexo dos animais (D). O modelo que melhor se ajustou às evidências obtidas na pesquisa foi o quadrático. A cama de frango nos níveis testados e a uréia no menor nível não devem ser usadas para o confinamento de ovinos da raça Santa Inês. O uso de 60% de ração com uréia diminui os custos da alimentação e proporciona maior ganho de peso, podendo substituir com vantagem econômica a cama de frango. A idade ótima de abate é de 65 dias.

The objective of the present paper is to estimate the economic feasibility of using urea in two food supplements: standard ration and chicken litter. This food supplement is combined with grazing elephant grass to feed sheep of the Santa Inês breed. In this sense, we adjusted a production function using experimental data, to determine the maximum net income, the time horizon of slaughter and the maximum period to confine the animal when the net income is set to zero. 40 sheep, 20 males and 20 female confined were utilized for 70-day period. The experimental design consisted of randomized blocks with five treatments and four replications. The treatments were the following: I - 50% grazing elephant grass hay plus 50% standard ration: II - 60% grazing elephant grass hay plus 40% ration with chicken litter; III - 40% grazing elephant grass plus 60% ration with chicken litter; IV - 60% grazing elephant grass hay plus 40% ration with urea; and V - 40% grazing elephant grass hay plus 60% ration with urea. The dependent variable used in the adjustment was the weight gains in confinement (Y), and the explanatory variables were the time period of 14 days (T) and dummy variable (D) related to animal Sex. The results indicate that the best model was quadratic models. It also demonstrated that the chicken litter in both levels and the urea in the lower level can not be used in the confinement of the Santa Inês sheep. The use of 60% ration with urea decreases food cost and increases weight gain. Therefore, the treatment V can be replaced with chicken litter in sheep feeding. The ideal age of slaughtering sheep was estimated at 65 days.