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No decurso do tempo, vários povos deixaram-se levar, por conhecimentos empíricos, pela condução da natureza, movidos, dentre outros motivos, por crenças e mistérios ainda não desvendados completamente pela ciência moderna, como a influência das fases lunares durante o ciclo de vida das plantas. O objetivo deste trabalho foi avaliar as interações que ocorrem entre as fases da Lua e a posição da estaca no ramo no desenvolvimento de mudas de macaxeira. A pesquisa foi conduzida na área experimental do Núcleo de Planta Aromáticas e Medicinais – NUPLAM, do Cento de Ciências Agrárias – CCA da Universidade Federal do Piauí – UFPI, no período compreendido entre setembro e novembro de 2017. O delineamento utilizado foi blocos casualizados (DBC) com doze tratamentos, dispostos em arranjo fatorial 4x3 e três repetições. Os tratamentos foram compostos pelas fases da Lua: Lua nova (LN); Lua crescente (LC); Lua cheia (LCO) e Lua minguante (LM) e três posições das estacas no ramo: estaca ponteira (EP); estaca mediana (EM) e estaca basal (EB). Os parâmetros avaliados foram: peso da fitomassa fresca da parte aérea (PFFA) e da raiz (PFFR) e peso da fitomassa seca da parte aérea (PFSA) e da raiz (PFSR). Os melhores resultados foram proporcionados pelas fases da lua minguante e cheia e, as posições das estacas no ramo, basal e mediana. In the course of time, various peoples were led by empirical knowledge to the conduct of nature, driven, among other reasons, by beliefs and mysteries not yet completely revealed by modern science, such as the influence of the lunar phases during the life cycle of plants. The objective of this work was to evaluate the interactions that occur between the phases of the Moon and the position of the stem in the branch in the development of seedlings of cassava. The research was conducted in the Experimental Area of the Nucleus of Aromatic and Medicinal Plants - NUPLAM, Cento of Agricultural Sciences - CCA of the Federal University of Piauí - UFPI, in the period between September and November of 2017. The design used was randomized blocks (DBC) with dose treatments, arranged in a 4x3 factorial arrangement and three replicates. The treatments were composed by the phases of the Moon: New Moon (LN); Crescent Moon (LC); Full moon (LCO) and waning moon (LM) and three positions of the cuttings in the branch: stake pointer (EP); staking (EM) and basal cutting (EB). The parameters evaluated were: fresh shoot weight (PFFA) and root (PFFR) weight and dry shoot weight (PFSA) and root weight (PFSR). The best results were provided by the phases of the waning and full moon and the positions of the stakes in the branch, basal and median. A lo largo del tiempo, varios pueblos se dejaron llevar, por el conocimiento empírico, por la guía de la naturaleza, impulsados, entre otras razones, por creencias y misterios aún no del todo desentrañados por la ciencia moderna, como la influencia de las fases lunares durante la ciclo de vida de las plantas. El objetivo de este trabajo fue evaluar las interacciones que se dan entre las fases de la Luna y la posición de la estaca en la rama en el desarrollo de plántulas de yuca. La investigación se realizó en el área experimental del Núcleo de Plantas Aromáticas y Medicinales - NUPLAM, del Cento de Ciências Agrárias - CCA de la Universidad Federal de Piauí - UFPI, en el período comprendido entre septiembre y noviembre de 2017. El diseño utilizado fue bloques al azar (DBC) con doce tratamientos, dispuestos en un arreglo factorial 4x3 y tres repeticiones. Los tratamientos estuvieron compuestos por las fases de la Luna: Luna Nueva (LN); luna creciente (LC); Luna llena (LCO) y luna menguante (LM) y tres posiciones de estaca en el ramal: punta estaca (EP); corte mediano (EM) y corte basal (EB). Los parámetros evaluados fueron: fitomasa fresca de brote (PFFA) y raíz (PFFR) y fitomasa seca de brote (PFSA) y raíz (PFSR). Los mejores resultados fueron proporcionados por las fases de luna menguante y llena y las posiciones de las estacas en la rama, basal y mediana. more...

This study was undertaken to compare different non-linear models for fitting growth curves of Polled Nellore animals as well as to estimate genetic parameters for the components of the growth curve. The study involved body weight-age data of 6,717 Polled Nellore cattle from birth to 650 days of age, which belonged to the Brazilian Association of Zebu Breeders (ABCZ), corresponding to the period from 1980 to 2011. Four non-linear models (Brody, Bertalanffy, Logistic, and Gompertz) were fitted and compared by the adjusted coefficient of determination (R2adj), mean absolute deviation of residuals (MAD), root mean square error (RMSE), Akaike information criterion (AIC), and Bayesian information criterion (BIC). To estimate the genetic parameters and genetic values of asymptotic weight (A), integration constant (B), and maturation rate (K), the Bayesian inference method was adopted. The Brody model showed the lowest values of MAD, RMSE, AIC, and BIC and the highest R2adj. Heritability estimates for parameters A, B, and K were 0.11, 0.16, and 0.30, respectively, whereas genetic correlations were 0.01 (A-B), -0.91 (A-K), and 0.24 (B-K). The Brody model provided the best fit. The K parameter shows enough genetic variability for selection in the herd. Heavier animals in adulthood tend to exhibit lower growth rates. Despite the low heritability estimate of parameter A, there were genetic gains, indicating that selection is being efficient on asymptotic weight. more...

B-spline functions have been used in random regression models (RRM) to model animal weight from birth to adulthood because they are less vulnerable to common difficulties of other methods. However, its application to model growth traits of Polled Nellore cattle has been little studied. Therefore, this study aimed to evaluate polynomial functions of different orders and segment numbers to model effects associated with the Polled Nellore cattle growth curve. For this purpose, we used 15,148 weight records of 3,115 animals aged between 1 and 660 days and reared in northern Brazil and born between 1995 and 2010. Random effects were modeled using B-spline polynomials. As random effects, we considered the direct and maternal genetic additives, as well as direct and maternal permanent environments. As fixed effects were included contemporary group, cow age at calving (linear and quadratic) and fourth-order Legendre polynomials to represent average growth curve. The residue was modeled by considering seven age classes. The best-fitted model was the one that considered cubic B-spline functions with four knots for direct additive genetic effects and three knots for maternal genetic, animal permanent environment, and maternal permanent environment effects (C6555). Therefore, covariance functions under B-spline polynomials are efficient and can be used to model the growth curve of Polled Nellore cattle from birth to 660 days of age. Os modelos de regressão aleatória (MRA) aplicando funções B-spline são uma alternativa para modelar pesos do nascimento até a idade adulta dos animais, pois estas funções são menos vulneráveis as dificuldades constantemente observadas em outras metodologias. No entanto, são escassas pesquisas sobre aplicação destas funções sobre as características de crescimento em bovinos Nelore Mocho. Funções polinomiais de diferentes ordens e números de segmentos foram avaliadas na modelagem dos efeitos associados à curva de crescimento de bovinos da raça Nelore Mocho. Foram utilizados 15.148 registros de peso de 3.115 animais com idade entre 1 e 660 dias, criados na região norte do Brasil e nascidos entre 1995 e 2010. Os efeitos aleatórios foram modelados usando polinômios do tipo B-splines. Como efeitos aleatórios, foram considerados os efeitos genéticos aditivo direto e materno e os efeitos de ambientes permanentes direto e materno. Foram considerados como efeitos fixos, os grupos de contemporâneos, a idade da vaca ao parto (efeito linear e quadrático) e os polinômios de Legendre de quarta ordem, representando a curva média de crescimento. O resíduo foi modelado por meio de sete classes distribuídas segundo a idade. O modelo que considerou funções B-splines cúbicas com quatro nós para o efeito genético aditivo direto e três nós para os efeitos genético materno, ambiente permanente animal e ambiente permanente materno (C6555) foi o mais adequado. Concluiu-se que funções de covariâncias sob polinômios B-splines são eficientes e podem ser utilizados como alternativas para modelar a curva de crescimento de bovinos da raça Nelore Mocho do nascimento até 660 dias de idade. more...

O objetivo é abordar assuntos sobre polinômios B-splines utilizados em funções de covariância por meio de modelos de regressão aleatória com a finalidade de predizer o potencial genético em bovinos de corte em características de crescimento. Nos modelos de regressão aleatória é possível decompor a trajetória da curva de crescimento por meio das mudanças nas covariâncias dos efeitos aleatórios. O tipo e a ordem de ajuste dos polinômios utilizados para modelagem do crescimento podem influenciar os resultados das avaliações genéticas, portanto, é necessário avaliar diferentes modelos para se auferir o mais harmônico. Nesse contexto, o uso de polinômios segmentados do tipo B (Funções B-splines) tem sido proposto como alternativa aos polinômios de Legendre, no ajuste das funções de covariância. Atualmente, alguns autores concluíram que o uso de polinômios B-splines nos modelos de regressão aleatória apresentou vantagens em relação aos demais, porém, ainda não está claro alguns aspectos quanto à quantidade, ordem e posição dos nós para modelagem da curva. more...

The objective of this research was to evaluate the production of milk and goat production systems of the Saanen breed in Brazil. Dairy goat farming is being established in the Brazilian semiarid as a profitable agricultural activity with aptitude for the north-eastern semiarid, where it is not required a lot of investments and large areas for development of this activity, and for these reasons, it is one of the alternatives suitable for generation of employment and income in rural areas, especially for small and medium farmers who live in agrarian reform settlements and traditional rural communities. Thus, it is necessary to increase the milk production of goats through the use of animals from specialized breeds, as the Brazilian genetic material is heterogeneous and not specialized for this activity. more...

The purpose of this review is to show the increase in number of researches on covariance components and genetic evaluation using random regression models (RRM) for growth traits of Nellore cattle. Random regression models, also known as infinite-dimension models have been used to estimate variance components and genetic parameters for weight of beef cattle. In addition, those models are a standard alternative for genetic analyses of longitudinal data, however, the availibility of computational resources for performing genetic evaluations widely is an obstacle. Traits related to animal growth are adopted as selection criteria in beef cattle breeding programs, because the remuneration of cattle breeders is made based on the weight of carcasses. In recent years, RRM have been adopted as standard procedure in relation to the analysis of longitudinal data in animal breeding. more...

This review aimed to estimate covariance components for Tabapuã the growth characteristics in Brazil, using random regression models. The random regression models (MRA) make it possible to estimate coefficients of the covariance functions by the method of restricted maximum likelihood. These are suitable for longitudinal data analysis models, because of the deficiencies of conventional methods of quantitative genetic analysis, which are considered phenotypic values inherently continuous processes, as discrete processes. The covariance functions show the statistical correlation between two features of a trajectory at different points of same, ie that present in the arrangement have the same direction and magnitude. With the current concern of cutting bovinocultores regarding the growth of animals, the use of methods or techniques that provide increasingly accurate assessments of genetic parameters to be used in studying the development of animals for meat production is relevant more...

In this review, we compile information about the physiologic responses of goats to north-eastern Brazil’s semiarid environment and suggest some strategies to avoid the thermal discomfort of these small ruminants. Due to recent weather changes, the number of studies seeking to improve animal welfare has intensified to minimize the economic losses on animal production in the tropics. Among the climatic variables, the high room temperature, air humidity, and direct solar radiation are the main causes of physiological discomfort in animals that decrease their productivity. Therefore, it is very important to study the components that interact in the thermoregulation process, the consequences of disequilibrium in this process, and ways to ease these effects, aiming to provide thermal comfort to and seek the animal welfare of the animals. Therefore, it is essential to know the interaction between animals and the environment and the adaptability of the species and breeds that are exploited to make decisions about farming systems and management strategies to maximize productivity. more...

The purpose of this study was to evaluate the feeding behavior of sheep Santa Ines in semi-intensive farming system, fed concentrated and bulky. The experiment was conducted at Fazenda entanglement Latitude, 4th 45'15. 50' '5 S, Longitude 440° 00' 54 85'' The Cajazeiras in district 45 km from the city of Codo - MA. 12 aged male sheep were used at the beginning of the experiment between 4-5 months and at the end with 5-6, which were previously weighed and wormed (Allpar), divided into pasture and housed in open shed, covered with ceramic tiles and concrete floor with individual stalls of 12.00 m2 each, equipped with feeder and drinker. The mass bit and bit rate was no significant difference between treatments, and the supplementation showed a higher average (p more...

O objetivo desta revisão de literatura é compilar informações e reunir resultados de estimativas de parâmetros genéticos para características de crescimento de bovinos da raça Tabapuã, as características foram: peso ao nascimento (PN), peso a desmame (PD), peso ao ano (PA) e peso ao sobreano (PS). As características de crescimento são de grande importância para a produção animal e tem despertado interesse de pesquisadores da área de melhoramento genético animal. Na literatura, diferentes estimativas de parâmetros genéticos foram encontradas, onde a grande maioria é de média a alta magnitude, mostrando grande variabilidade genética, indicando que é um bom indicador de resposta à seleção. Dessa forma é relevante o conhecimento dos parâmetros genéticos para estas características em bovinos da raça Tabapuã, visto que esta raça nos últimos tempos vem contribuindo para o incremento na pecuária de corte brasileira. more...

The objective of this research is to estimate the genetic parameters and covariance components for growth characteristics in cattle from Tabapua breed through random regression models (RRM). The estimates of covariance functions are considered nowadays, interesting alternatives to work with longitudinal data that allow the description of covariances changes due to time and prediction of variances and covariances along the growth curve. The RRM has been used to estimate the variance components and genetic parameters of milk production on the control day of the lactation curve and meat production in many species, including bodyweight of beef cattle and among these the cattle from Tabapua breed, enabling us to work with features of growth curves that are measured repeatedly during the animal's life, known as longitudinal data. These models used in genetic evaluation in cattle are considered special cases of covariance functions that allow estimation of coefficients of genetic covariance functions directly through the method of restricted maximum likelihood. more...

B-spline functions have been used in random regression models (RRM) to model animal weight from birth to adulthood because they are less vulnerable to common difficulties of other methods. However, its application to model growth traits of Polled Nellore cattle has been little studied. Therefore, this study aimed to evaluate polynomial functions of different orders and segment numbers to model effects associated with the Polled Nellore cattle growth curve. For this purpose, we used 15,148 weight records of 3,115 animals aged between 1 and 660 days and reared in northern Brazil and born between 1995 and 2010. Random effects were modeled using B-spline polynomials. As random effects, we considered the direct and maternal genetic additives, as well as direct and maternal permanent environments. As fixed effects were included contemporary group, cow age at calving (linear and quadratic) and fourth order Legendre polynomials to represent average growth curve. The residue was modeled by considering seven age classes. The bestfitted model was the one that considered cubic B-spline functions with four knots for direct additive genetic effects and three knots for maternal genetic, animal permanent environment, and maternal permanent environment effects (C6555). Therefore, covariance functions under B-spline polynomials are efficient and can be used to model the growth curve of Polled Nellore cattle from birth to 660 days of age. Made available in DSpace on 2021-10-14T13:00:25Z (GMT). No. of bitstreams: 1 43198-226505-1-PB-publicado-13out2021-DanielleAzevedo.pdf: 1725153 bytes, checksum: 17e76946044861cf748099643b15850e (MD5) Previous issue date: 2021 more...

O objetivo deste trabalho foi estimar os parâmetros genéticos para as características peso ao desmame (P205), ao ano (P365) e sobreano (P550) de bovinos Nelore Mocho, criados na região Norte do Brasil. Foram utilizados 39.737 registros de peso pertencentes a 8.530 animais. Os parâmetros genéticos foram obtidos utilizando-se o método da máxima verossimilhança restrita (REML) sob o modelo animal, usando aplicativo computacional WOMBAT. O modelo empregado incluiu efeitos fixos de grupo de contemporâneos (sexo, fazenda, ano e estação de nascimento do animal) e idade da vaca ao parto como covariáveis (efeito quadrático), além de efeitos aleatórios genético aditivo direto, genético materno e ambiente permanente materno, adotando-se o modelo multicaracteristicas. Os coeficientes de herdabilidade direta estimados para as características estudadas foram de média a alta magnitude, variando de 0,32 (P550) a 0,50(P205), mostrando alta variabilidade genética e potencial de ganhos considerável utilizando essas características para a seleção. A herdabilidade materna foi de baixa magnitude, variando de 0,07 (P550) a 0,09 (P205) indicando diminuição do efeito materno ao longo do crescimento do animal. As correlações genéticas entre as características foram altas, positivos e superiores a 0,84, evidenciando alta associação entre as características, podendo-se obter ganhos genéticos via resposta correlacionada para P365 e P550 ao selecionar o P205. Entretanto, observam-se indicativas de que as características avaliadas são passíveis de seleção para o melhoramento genético da raça Nelore Mocho criados na região Norte do Brasil Made available in DSpace on 2020-10-21T09:13:33Z (GMT). No. of bitstreams: 1 EstimacaoParametrosGeneticosBovinoNeloreLRRD10.2020.pdf: 77105 bytes, checksum: 431aa5cb5e05f5b126ad0d35913e33ab (MD5) Previous issue date: 2020 more...