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RESUMO Objetivou-se avaliar o poder preditivo do modelo do National Research Council (NRC) para gado leiteiro em estimar o consumo de matéria seca (CMS) por vacas mestiças, em pastagens tropicais. Foi efetuada uma análise conjunta de cinco estudos, contemplando três forrageiras. Foram avaliadas 132 estimativas individuais do CMS observado (CMSObs), obtidas por meio do indicador externo Cr2O3. O CMS também foi predito por meio do software do NRC (CMSPred), que, por sua vez, foi abastecido com inputs referentes aos animais e ao ambiente de criação. Os valores de CMSPred (12,7±1,6kg/d) foram semelhantes aos de CMSObs (12,3±3,3kg/d). Foram obtidas as seguintes estimativas da avaliação do poder preditivo do modelo: viés médio (-0,419kg/d), coeficiente de determinação (0,029), coeficiente de correlação (0,17; P=,051), quadrado médio do erro de predição (11,844±20,034), fator de eficiência do modelo (-0,081), coeficiente de determinação do modelo (4,1032) e fator de correção do viés (0,767). A comparação entre CMSObs e CMSPred permitiu identificar a tendência de superestimação das predições se considerado o ajuste por meio de regressão robusta para o modelo linear simples sem intercepto. Nas condições avaliadas, o modelo produz predições de CMS com satisfatória exatidão, porém com baixa precisão.

The objective of this work is to evaluate the efficiency of genomic selection (GS) of genome-enabled prediction by Radial Basis Function Neural Networks (RBFNN) in the prediction of genetic values considering dominance effects and diferent degrees of heritability. In addition, the results were compared with those obtained by G-BLUP. An F1 population with 500 individuals genotyped with 1000 SNP-type markers was simulated. The phenotypic traits were determined by adopting two different gene action models: additive and dominance admitting heritability levels (h2) 30 and 60%, each is controlled by 50 loci, considering two alleles per loco. The accuracy and the mean squared error root (MSER) were estimated using a five-fold cross-validation scheme. For the low heritability scenario, h2 = 0.3 in the additive scenario, the accuracy of validation was 31% for RBFNN, 58% for RR-BLUP, and in the complete dominance scenario the values were 28% e 25%, respectively. Additionally, when analyzing the MSER the difference in performance of the techniques is even greater. For additive scenario, the estimates were 97.33 RR-BLUP and 5.80 for RBFNN, in the most critical scenario, 91.31 GBLUP and 14.55 for RBFNN. Overall, a RBFNN shows accuracy lower than those obtained through G-BLUP. On the other hand, the RBFNN has low prediction bias. Finally, the adjustment of the GBLUP to dominance models despite increasing the complexity of the model also increased the predictive accuracy compared to the model without considering the dominance effect.

Hamiltonian Monte Carlo (HMC) is an algorithm of the Markov Chain Monte Carlo (MCMC) method that uses dynamics to propose samples that follow a target distribution. This algorithm enables more effective and consistent exploration of the probability interval and is more sensitive to correlated parameters. Therefore, Bayesian-HMC is a promising alternative to estimate individual parameters of complex functions such as nonlinear models, especially when using small datasets. Our objective was to estimate genetic parameters for milk traits defined based on nonlinear model parameters predicted using the Bayesian-HMC algorithm. A total of 64,680 milk yield test-day records from 2,624 first, second, and third lactations of Saanen and Alpine goats were used. First, the Wood model was fitted to the data. Second, lactation persistency (LP), peak time (PT), peak yield (PY), and total milk yield [estimated from zero to 50 (TMY50), 100(TMY100), 150(TMY150), 200(TMY200), 250(TMY250), and 300(TMY300) days-in-milk] were predicted for each animal and parity based on the output of the first step (the individual phenotypic parameters of the Wood model). Thereafter, these predicted phenotypes were used for estimating genetic parameters for each trait. In general, the heritability estimates across lactations ranged from 0.10 to 0.20 for LP, 0.04 to 0.07 for PT, 0.26 to 0.27 for PY, and 0.21 to 0.28 for TMY (considering the different intervals). Lower heritabilities were obtained for the nonlinear function parameters (A, b and l) compared to its predicted traits (except PT), especially for the first and second lactations (range: 0.09 to 0.18). Higher heritability estimates were obtained for the third lactation traits. To our best knowledge, this study is the first attempt to use the HMC algorithm to fit a nonlinear model in animal breeding. The two-step method proposed here allowed us to estimate genetic parameters for all traits evaluated.

In order to optimize the performance and reduce costs in the larviculture of ornamental carp ( Cyprinus carpio ) in a recirculating aquaculture system, different feeding strategies were tested. For this, two experiments were carried out both under controlled conditions in a greenhouse, in a recirculating aquaculture system with a physical particle filter, biofilter, and filtering by ultra-violet irradiation. In the first experiment, measurements of Artemia nauplii were tested in the initial exogenous feeding of larvae at concentrations of 100, 200, 400, 600, 800 and 1,000 Artemia nauplii per larvae. In the following experiment, different protocols were tested for initial feeding for larvae. At this stage, were used: live food ( Artemia nauplii) and inert (powder meal), used separately and simultaneously, and increases in the number of Artemia nauplii were also tested, offered at different times of cultivation. In the first experiment, the amount of 600 Artemia nauplii for larvae demonstrated to be the best option as it generated significant growth and the cost was less than that observed with the use of 800 and 1000 Artemia nauplii per larvae. The second experiment demonstrated that the feeding strategy with live food more commercial inert feed provided the best growth performance for ornamental carp larvae. The need to fix the amount of live food during the cultivation, probably due to the high specific growth rates observed during the larval stage also became evident.

Nematodes of the genus Libyostrongylus parasitize ostriches, causing high mortality rates. These nematodes are found in the proventriculus and ventriculus of ostriches, but little is known about their distribution and the possible anatomopathological changes they cause in the various regions of these organs. This paper describes the distribution and quantification of Libyostrongylus and pathological changes found in regions of the proventriculus and ventriculus of ostriches with high and low levels of both natural and experimental infection. Ostriches were necropsied and tissue samples from the distinct regions of both organs were analysed based on nematode counts and histopathology after staining with haematoxylin and eosin, Masson's trichrome or Alcian blue/PAS. The cranial and glandular regions of the proventriculus were the most parasitized. The ventriculus contained more nematodes in the caudal region. No macro- or microscopic pathological changes were observed in either of these organs of experimentally-infected birds. However, naturally-infected birds with high levels of infection presented proventriculus with macroscopic lesions and heterophilic infiltrates surrounding nematodes. In the glandular region of this organ, nematodes were located in the adenomeres of the secretory ducts, causing altered architecture and erosions and ulcerative lesions with damaged epithelium. Nematode eggs were found in the koilin layer of the middle and caudal regions of the ventriculus only of these birds. The pH of the regions assessed by Alcian blue/PAS staining changed from acidic in the proventriculus to more alkaline in the caudal region of the ventriculus. These data add knowledge to the biology of Libyostrongylus. RESEARCH HIGHLIGHTS The most parasitized areas were the cranial and glandular regions of the proventriculus. Naturally-infected birds with high levels of infection presented macro lesions in the proventriculus and damaged epithelium. Nematode eggs were found in the ventriculus. The proventriculus had an acidic pH, which turned alkaline towards the ventriculus.

Markers are an important tool in plant breeding, which can improve conventional phenotypic breeding, generating more accurate information outcoming better decision making. This study aimed to apply and compare the fit of different Bayesian models BRR, BayesA, BayesB, BayesB (setting the value from very low to $$\pi$$ π = $${10}^{-5}$$ 10 - 5 ), BayesC and Bayesian Lasso (LASSO) for predictions of the genomic genetic values of productivity and quality traits of a guava population. The models were fitted for traits fruit mass, pulp mass, soluble solids content, fruit number, and production per plant in the genomic prediction with SSR markers, obtained through the CTAB extraction method with 200 primers. The Bayesian ridge regression model showed the best results for all traits and was chosen to predict the individual’s genomic values according to the cross-validation data. A good stabilization of the Markov and Monte Carlo chains was observed with the mean values close to the observed phenotypic means. Heritabilities showed good predictive accuracy. The model showed strong correlations between some traits, allowing indirect selection.

Background : The enzootic bovine leukosis (EBL) is a viral disease with a chronic aspect and its etiological agent is an oncogenic deltaretrovirus called bovine leukemia virus (VLB). It has a wide distribution in dairy cattle herds, and it may take several years before the first clinical manifestations occur. Animals seropositive for VLB are more susceptible to developing infectious diseases such as mastitis. The objective of this study was to evaluate the seroprevalence of EBL, the prevalence of mastitis, the possible association between leukosis and mastitis, and the risk factors related to leukosis in municipalities of the Caparao region of Espirito Santo, Brazil. Materials, Methods & Results : The prevalence of enzootic bovine leukosis and its association with mastitis were evaluated in an 854 clinically healthy crossbred ( Bos tauros tauros x Bos taurus indicus ) dairy cows were used, in different lactation phases, from farms located in the 12 municipalities that compose the Caparao Capixaba micro-region, in the southern part of Espirito Santo, Brazil, in the period from February to July 2015. The seroprevalence of EBL was determined by the agar gel immunodiffusion test, the presence of clinical mastitis was ascertained by the black background mug test and of subclinical mastitis by the CMT. The reuse of needles, type of milking, reproductive management, calf mortality, presence of reproductive problems and milk yield were the risk factors assessed. The association between the variables was estimated by the odds ratio (95% confidence interval). The significance of the associations was determined by the Chi-square test. The prevalence of EBL, clinical and subclinical mastitis was 56.79%, 5.50% and 43.55%, respectively. There was a positive association between the EBL virus and the presence of subclinical mastitis ( P < 0.05, OR = 1.41, CI = 1.07-1.86). The reuse of disposable needles (OR = 1.92, CI = 1.46-2.53), mechanical milking (OR = 2.03, CI = 1.34-3.08), calf mortality (OR = 2.39; CI = 1.25-4.55) and the presence of reproductive problems (OR = 1.62; CI = 1.23-2.14) were considered risk factors associated with LEB ( P < 0.05). Discussion : Enzootic bovine leukosis is disseminated in the dairy herds in the municipalities the study. The lack of knowledge about EBL among farmers and the failure to adopt measures for its control and elimination favor the appearance of new cases in the herd. Factors such as animal age, absence of exams when purchasing animals, reuse of gloves for rectal palpation and needles, contribute to dissemination of the infection. The economic losses associated with subclinical mastitis can even be greater than those caused by clinical mastitis. The differences for prevalence of clinical mastitis can be associated with the breeding system, type of management, intensification and level of production. In this context, we noted a much larger number of animals with subclinical infection, where the losses may not be perceptible to the farmers. It is concluded that EBL is widespread in dairy herds of the municipalities of Caparao Espirito Santo's region. The prevalence of clinical and subclinical mastitis is high in some cities surveyed. The presence of EBL increases the chances of developing subclinical mastitis. The reuse of disposable needles and mechanical milking were considered risk factors associated with EBL. Seroreagent animals for EBL are more likely to present calf mortality and reproductive problems. It is necessary to discuss the best sanitary management system for the region, with a better economic and social response and then carry out the elaboration of educational and implementation measures, through technical assistance.

Aim of study: to analyse the effect of stocking density on common carp larvae production. Since stocking density is one of the most important variables in recirculating aquaculture system, it is fundamental to understand its implication on fish larval development. Area of study: BrazilMaterial and methods: In an initial trial over a 30-day period, 18,000 Cyprinus carpio larvae were subjected to eight different stocking densities (5, 10, 15, 20, 25, 30, 35 and 40 larvae/L). In a second trial over a 15-day period, the larvae subjected to the 40 larvae/L treatment were selected according to size and 360 of them were subjected to restocking processes at a density of 5 larvae/L, in order to evaluate possible compensatory growth, while those subjected to the 5 larvae/L treatment were likewise selected according to size and were distributed at the same stocking density (5 larvae/L), to be the control treatment during the restocking process.Main results: The larvae kept at the density of 5 larvae/L showed better growth and development. Increased heterogeneity of the concomitant batch was observed with higher stocking density. Restocking at low density (5 larvae/L), for larvae that had previously been kept at high density (40 larvae/L), caused partial compensatory growth, with an increase in the specific growth rate. Increasing the density caused increased productivity up to the density level of 25 larvae/L, but from then on there was no significant difference (p > 0.05).Research highlights: Carp larvae reared at high densities need to be restocked during rearing in order to avoid the “shooting” problem.

Medicinal plants have been the focus of several studies due to their nematicide properties which can be used to control nematodes in sheep. No study has examined the morphological effects of Cymbopogon citratus on nematodes. Thus, this study evaluated the chemical composition, nematicidal activity and effects of C. citratus extracts on the morphology of eggs and infective larvae (L3) of sheep. Aqueous and methanolic extracts and fractions of C. citratus were obtained and analysed in vitro. The C. citratus extracts were effective against Haemonchus spp. and Trichostrongylus spp. larvae and eggs. Ten fractions were obtained from C. citratus, six of which had high ovicidal activity at 1000 μg mL−1, and two fractions had high activity at all tested concentrations. The phytochemical analysis identified the presence of compounds such as terpenoids, various ketones, esters, and fatty acids. The ultrastructural analysis showed deformations of the cuticle and wilting along the body of the nematodes at all concentrations. The muscular layer, intestinal cells and the mitochondria profile showed damage compared to the typical pattern. Ultra-thin sections of eggs treated with methanolic fractions of C. citratus presented modifications. This study showed the biological activity and effects of C. citratus on the gastrointestinal nematodes in sheep.

The Golden hamster has been gaining significance as a new experimental biomodel, finding use as a reliable diagnostic tool in biomedical research and for zoonosis. Authentic data in terms of digestibility, interactions among raw materials and essential nutrients, besides the influence exerted by various sterilization processes on animal behavior remain unclear. We aimed to assess the influence of sterilization, via autoclaving and irradiation, of pellet feeds prepared using salmon or linseed oil on the digestibility and plasma biochemical parameters in Golden hamsters. Randomized evaluations were conducted on 36 adult male Golden hamsters (Mesocricetus auratus), distributed in six treatments and six replications, namely: common salmon oil; radiated salmon; autoclaved salmon; common linseed oil; radiated linseed and autoclaved linseed. A remarkable effect of the sterilization was evident on the digestibility and protein solubility of the feed, which was lower for autoclaved diets. There was also a significant effect on blood parameters. Animals fed diets containing linseed oil showed lower blood glucose compared to the others. Thus, the inference reached was that while salmon and linseed oil can be used in laboratory hamster feeds, autoclaving disturbs the nutritional quality of the rations. Resumo O hamster Golden é um importante biomodelo utilizado na pesquisa biomédica e como meio de diagnóstico para zoonoses. Informações de qualidade, digestibilidade, interações das matérias primas e exigências nutricionais, assim como os efeitos decorrentes dos diferentes processos de esterilização sobre o desempenho animal ainda são desconhecidos. Objetivou-se com esse estudo avaliar os efeitos da esterilização por autoclavagem e irradiação de rações peletizadas, formuladas com óleo de salmão ou linhaça, sobre a digestibilidade e parâmetros bioquímicos plasmáticos de hamsters Golden. Foram avaliados 36 hamsters Golden (Mesocricetus auratus), machos adultos distribuídos em delineamento experimental inteiramente casualizado com seis tratamentos e seis repetições, a saber: óleo de salmão comum; salmão irradiada; salmão autoclavada; óleo de linhaça comum; linhaça irradiada e linhaça autoclavada. Houve efeito significativo da esterilização sobre a digestibilidade e solubilidade proteica da ração, que foi pior para as rações autoclavadas. Também houve efeito significativo sobre os parâmetros sanguíneos. Animais alimentados com rações contendo óleo de linhaça apresentaram glicemia mais baixa em comparação aos demais. Conclui-se que o óleo de salmão e linhaça pode ser utilizado em rações para hamsters de laboratório, porém a autoclavação interfere na qualidade nutricional das dietas.

The objective of this study was to nutritionally evaluate the use of pineapple crop waste silage in the feeding of growing bull in different planes of nutrition. We used eight non-castrated growing bull housed in individual covered pens, provided with free access to water and individual trough. Two balanced Latin squares conducted simultaneously were used. Treatments consisted of four planes of nutrition (L), formed by multiples of maintenance, i.e., L = ME/Mm; they were ME/Mm, ME/1.5Mm, ME/2Mm, and ME/2.7Mm. The intake of nutrients in diets was determined by the difference between the total mass of food offered and the mass of orts. To determine nutrient digestibility and nitrogen balance, total feces, and urine, collections were performed for seven consecutive days in each animal per period. The increase in planes of nutrition affected (P < 0.05) nutrient intake between L = 1 and L = 1.5. However, there was no effect nutrients intake to 1.5, 2, and 2.7. Nutrient digestibility was affected by the increase in planes of nutrition (P < 0.05), except for dCF (P = 0.0659). Digestible and metabolizable energies were affected (P < 0.05) by the increase in nutritional plans, as well as nitrogen balance. In conclusion, the pineapple crop waste silage presents itself as a good forage alternative for cattle diets, especially during forage shortage periods. Inclusion in the diet at 2.7 × the maintenance level does not compromise growing bull performance. However, the increases in planes of nutrition reduce the digestible energy contents of the diet.

Perennial breeding species demand substantial investment in various resources, mainly the required time to obtain adult and productive plants. Estimating several genetic parameters in these species, in a more confidence way, means saving resources when selecting a new genotype. A model using the Bayesian approach was compared with the frequentist methodology for selecting superior genotypes. A population of 17 families of full-siblings of guava tree was evaluated, and the yield, fruit mass, and pulp mass were measured. The Bayesian methodology suggest more accurate estimates of variance components, as well as better results to fit of model in a cross-validation. Proper priori for Bayesian model is very important to convergency of chains, mainly for small datasets. Even with poor priori, Bayesian was better than frequentist approach.

The goal of our study was to evaluate the quality of fit from different types of probability distributions for continuous data. For this, performance traits and quality of quail egg in the production of nutraceutical eggs were used as a continuous data source. The data were collected over 42 days, the experimental design was completely randomized with 7 treatments, 6 repetitions, with 252 animals allocated in 36 cages. The distributions for continuous data used were the exponential, gamma, gaussian, and lognormal. The R Open Source and SAS® University Edition software was used to perform the analysis. The graphical analysis of the traits was performed from the predicted versus observed values, Cumulative Distribution Function (CDF), and skewness-kurtosis. The fits were also evaluated by the Akaike information criterion (AIC), Bayesian information criterion (BIC), Conditional model of adjusted R-Square (), Conditional model of adjusted concordance correlation (), Kolmogorov-Smirnov test (KS), Cramer-von Mises test (CvM), Anderson-Darling test (AD), Watanabe-Akaike Information Criterion (WAIC) and Leave-one-out cross-validation (LOO). All the tests indicated the Gaussian distribution as the most suitable and they excluded the exponential distribution for all the evaluated characteristics. El objetivo de nuestro estudio fue evaluar la calidad del ajuste de diferentes tipos de distribuciones de probabilidad para datos continuos. Para ello, se utilizaron como fuente continua de datos las variables rendimiento y calidad del huevo de codorniz en la producción de huevos nutracéuticos. Los datos fueron recolectados durante 42 días, el diseño experimental fue completamente al azar con 7 tratamientos, 6 repeticiones, con 252 animales distribuidos en 36 jaulas. Las distribuciones para los datos continuos utilizadas fueron exponencial, gamma, gaussiana y lognormal. Se utilizó el software R Open Source y SAS® University Edition para realizar el análisis. El análisis gráfico de las variables se realizó a partir de los valores predichos versus los observados, la Función de Distribución Acumulativa (CDF) y la asimetría-curtosis. Los ajustes también se evaluaron mediante el criterio de información de Akaike (AIC), el criterio de información bayesiano (BIC), el modelo condicional de R-Cuadrado ajustado (), el modelo condicional de correlación de concordancia ajustada (), la prueba de Kolmogorov-Smirnov (KS), Prueba de Cramer-von Mises (CvM), prueba de Anderson-Darling (AD), criterio de información de Watanabe-Akaike (WAIC) y validación cruzada de dejar uno fuera (LOO). Todas las pruebas indicaron la distribución gaussiana como la más adecuada y excluyeron la distribución exponencial para todas las características evaluadas. O objetivo do nosso estudo foi avaliar a qualidade do ajuste de diferentes tipos de distribuições de probabilidade para dados contínuos. Para tanto, as variáveis desempenho e qualidade do ovo de codorna na produção de ovos nutracêuticos foram utilizadas como fonte contínua de dados. Os dados foram coletados ao longo de 42 dias, o delineamento experimental foi inteiramente casualizado com 7 tratamentos, 6 repetições, com 252 animais alocados em 36 gaiolas. As distribuições de dados contínuos usadas foram a exponencial, gama, gaussiana e lognormal. Os softwares R Open Source e SAS® University Edition foram usados para realizar a análise. A análise gráfica das variáveis foi realizada a partir dos valores previstos versus observados, Função de Distribuição Cumulativa (CDF) e assimetria-curtose. Os ajustes também foram avaliados pelo critério de informação de Akaike (AIC), critério de informação Bayesiano (BIC), modelo condicional de R-quadrado ajustado (), modelo condicional de correlação de concordância ajustada (), teste de Kolmogorov-Smirnov (KS), Teste de Cramer-von Mises (CvM), teste de Anderson-Darling (AD), Critério de informação Watanabe-Akaike (WAIC) e validação cruzada de deixar um de fora (LOO). Todos os testes indicaram a distribuição gaussiana como a mais adequada e excluíram a distribuição exponencial para todas as características avaliadas.

We aimed with this study to combine Legendre polynomials (LEG) and linear B-splines (BSP) to describe simultaneously the first and second lactation of Gyr dairy cattle under a multiple-trait random regression models (MTRRM) framework. Additionally we proposed the application of self-organizing map to define the classes of residual variances under these models. A total of 26,438 and 23,892 milk yield test-day records were used, respectively, for the first and second lactations of 3253 Gyr cows. Two preliminary MTRRM analyses considering 10 residual classes were performed: the first one was based on LEG for systematic and random effects for both lactations; and the second one was based on BSP. Three classes were defined by using a self-organizing map: from 6 to 35; 36–185 and 186–305 days in milk. After definition of residual variance classes, a total of 16 MTRRM combining LEG and BSP were compared. The MTRRM based on BSP to describe the systematic effects of the first and second lactation, BSP to describe the random effects of the first lactation and LEG to describe the random effects of the second lactation (BSP-BSP-BSP-LEG) outperformed all other models. From the BSP-BSP-BSP-LEG model, heritability estimates for milk yield over time ranged from 0.1107 to 0.2902, and from 0.2036 to 0.3967, for the first and second lactation, respectively. In general, additive genetic correlation estimates between days in milk within each lactation and between lactations had medium magnitude (mean of genetic correlations were 0.6630, 0.6226 and 0.4749 for the first, second and between both lactations, respectively). We concluded that combining different functions under a MTRRM framework is a feasible alternative for genetic modeling of lactation curves in Gyr dairy cattle.

The purpose of this study was to evaluate the effect of interaction between increasing neutral detergent fiber content and particle sizes on ingestive behavior of dairy goats. Forty-eight lactating, multiparous Saanen and Alpine goats, with average milk production of 1.4 ±0.57 kg d-1, around 60th ±12 day of lactation were distributed in a 3 x 4 factorial completely randomized design. The diets consisted: three particles sizes (02, 05 or 15 cm) and four levels of neutral detergent fiber (34, 41, 49 or 57% NDFf) from forage (Tifton 85 hay). The ingestive behavior was monitored during 24 hours. A regression and a multivariate time series cluster analysis were performed. No interaction was found (p > 0.05) between treatments. Feeding time was different according to the particle size, having an increasing linear effect. Rumination and idle times were not affected (p > 0.05). The temporal feeding behavior was clustered into two groups according to the profile of particle size of the diet. Rumination peaks were randomly distributed with more intense activity before morning and afternoon meals. The increase in NDFf content in the diet did not change the ingestive behavior. The multivariate cluster analysis in a time series data is useful to interpret animal feeding behavior.

The knowledge of the dynamics of animal growth over time can be done through non-linear equations. Thus, the objective was to describe and compare the growth of three free-range chicken lineages based on the Gompertz equation. 180 unsexed chickens assigned to three treatments (Pesadão Vermelho, Pescoço Pelado and Carijó Pesado lineages) in a randomized design with six replicates, with 10 birds per experimental unit. Broilers were weighed weekly (until 77 days of age), these data were used to estimate the growth curve and determine the equation parameters (A, B and C) of model used. The comparison tests between the model parameters for each lineage, demonstrated that it is necessary an equation with different A, B and C parameters for each lineages, the lack-of-fit test was not significant (p>0.05), therefore, the equations of the model are suitable to describe the growth of the lineages. The Pesadão Vermelho lineages is heaviest at inflection point and earlier (BWe =1,528 g at 39 days of age), compared to the Pescoço Pelado (BWe=1,185 g at 38 days of age) and the Carijó Pesado (BWe=1,183 g at 51 days of age) lineage. The adjusted Gompertz curves accurately estimated growth curves of the evaluated line-ages. An equation with different A, B and C parameters is required for each lineage. The Pesadão Vermelho lineage is heaviest at maturity. The Carijó Pesado lineage has a slow growth, with low weight at maturity and the oldest age at maturity. El conocimiento de la dinámica del crecimiento animal a lo largo del tiempo se puede realizar mediante ecuaciones no lineales. Así, el objetivo era describir y comparar el crecimiento de tres linajes de pollos campesinos a partir de la ecuación de Gompertz. Se utilizaron 180 aves, distribuidas en tres tratamientos (linajes Pesadão Vermelho, Pescoço Pelado y Carijó pesado) en un diseño aleatorio con seis repeticiones, con 10 aves por unidad experimental. Los pollos fueron pesados cada semana (hasta los 77 días de edad) esta información se utilizó para estimar la curva de crecimiento y determinar los parámetros (A, B y C) del modelo utilizado. Las pruebas de comparación entre parámetros demostraron que cada linaje necesita una ecuación, con parámetros A, B y C diferentes, y la prueba para la falta de ajuste no fue significativa (p>0.05), las ecuaciones del modelo son adecuadas para describir el crecimiento de los linajes. El linaje Pesadão Vermelho presenta mayor peso en el punto de inflexión y mayor precocidad (BWe=1,528 g a los 39 días de edad), comparado con Pescoço Pelado (BWe=1,185 g a los 38 días de edad) y Carijó Pesado (BWe=1,183 g a los 51 días de edad). Las curvas de Gompertz ajustadas presentaron con exactitud las curvas de crecimiento de los linajes evaluados. Se requiere una ecuación con parámetros A, B y C diferentes para cada linaje. El linaje Pesadão Vermelho tiene el mayor peso a la madurez. El linaje Carijó Pesado presenta un crecimiento lento con bajo peso a la madurez y mayor edad a la madurez. O conhecimento da dinâmica de crescimento animal ao longo do tempo pode ser feito através de equações não lineares. Assim, objetivou-se descrever e comparar o crescimento de três linhagens de frangos caipiras a partir da equação de Gompertz. Foram utilizadas 180 aves distribuídas em delineamento inteiramente ao acaso com três tratamentos (linhagem Pesadão Vermelho, Pescoço Pelado e Carijó Pesado), seis repetições de 10 aves por unidade experimental. As aves foram pesadas semanalmente (até os 77 dias de idade), essas informações foram utilizadas para estimar a curva de crescimento e determinar os parâmetros (A, B e C) do modelo utilizado. Os testes de comparação entre parâmetros demonstram que cada linhagem necessita de uma equação com parâmetros A, B e C diferentes, o teste para a falta de ajustamento não foi significativo (p>0,05), portanto as equações do modelo são adequadas para descrever o crescimento das linhagens. A linhagem Pesadão Vermelho apresentou maior peso corporal no ponto de inflexão e maior precocidade (PCe=1.528 g aos 39 dias de idade), comparado a Pescoço Pelado (PCe=1.185 g aos 38 dias de idade) e Carijó Pesado (PCe=1.183 g aos 51 dias de idade). As curvas de Gompertz ajustadas estimaram com acurácia as curvas de crescimento das linhagens avaliadas, assim, é necessária uma equação com parâmetros A, B e C diferentes para cada linhagem. A linhagem Pesadão Vermelho apresentou maior peso à maturidade. A linhagem Carijó Pesado apresentou crescimento menor com baixo peso à maturidade e maior idade à maturidade.

SUMMARY We aimed to compare multi-trait and repeatability models to estimate genetic parameters for the traits number of piglets born alive (NBA) and alive at 3 week of age (NP3), litter weight at birth (LW0) and at 3 week of age (LW3), and mean piglet weight at birth (MW0) and at 3 week of age (MW3), considering the first three farrowings of Landrace sows. Heritability (h2) estimates showed an increasing pattern up to the third farrowing for LW0 and MW3. For NBA, NP3, LW3, and MW0 h2 increased from the first to the second and decreased from the second to the third farrowing. In general, heritability estimated in the repeatability model was lower than the mean of the estimates in the multi-trait model. The traits LWO, MW0, and MW3 presented high genetic correlation among different farrowings (0.961–0.997), while NBA, NP3, and LW3 (0.092–0.986) presented irregular values among farrowings. The corrected Akaike information criterion shows that the repeatability model is not indicated for almost all of the studied traits. These results indicate that the multi-trait model is recommended for genetic evaluation of the traits number of piglets born alive and alive at 3 week of age, litter weight and mean piglet weight at birth and 3 week of age, in different farrowings, as different traits. RESUMO Objetivou-se comparar os modelos multicaracterístico e de repetibilidade na estimação de parâmetros genéticos para as características número de leitões nascidos vivos (NLN) e às três semanas de idade (NL3), peso da leitegada ao nascimento (PLN) e às três semanas de idade (PL3), e peso médio do leitão ao nascimento (PMLN) e às três semanas de idade (PML3), considerando os três primeiros partos de fêmeas da raça Landrace. As estimativas de herdabilidade (h2) aumentaram até a terceira ordem de parto para as características PLN e PML3. Para NLN, NL3, PL3 e PMLN as h2 aumentaram da primeira para a segunda parição e reduziram da segunda para terceira parição. Em geral, as herdabilidades estimadas via modelo de repetibilidade foram menores que a média das estimativas obtidas utilizando o modelo muticaracterístico. As características PLN, PMLN e PML3 apresentaram altas correlações genéticas entre as diferentes parições (0,961–0,997), enquanto as características NLN, NL3 e PL3 (0,092–0,986) apresentaram valores irregulares de correlações genéticas entre as parições. Pelo critério de informação de Akaike corrigido o modelo de repetibilidade não foi indicado para a maioria das características estudadas. Esses resultados indicam que o modelo multicaracterístico é recomendado para avaliação genética das características número de leitões nascidos vivos e às três semanas de idade, peso da leitegada ao nascimento e às três semanas de idade e peso médio do leitão ao nascimento e às três semanas de idade, em diferentes parições, como características diferentes.

The objective of this study was to evaluate the intake and digestibility of silages containing pineapple pulp and coast-cross hay, with or without addition of urea, and the recovery of the markers chromium oxide (Cr2O3), indigestible neutral detergent fiber (iNDF), indigestible acid detergent fiber (iADF), and indigestible dry matter (iDM), in a digestibility assay, in sheep. Treatments were as follows: two levels of pineapple pulp (818 and 758 g kg−1) and two levels of urea (with and without urea), in a completely randomized design. Twelve sheep (three per treatment) were used, kept in metabolic cages. Fecal excreta were determined by total collection or estimated by using the markers. Marker samples were obtained in morning and afternoon collections, with mean concentrations obtained for both daily activities. The level of silage pulp did not affect intake, while addition of urea increased the intake of crude protein (CP), but did not influence the intakes of dry matter, organic matter, neutral detergent fiber, or acid detergent fiber. The digestibility coefficients of all afore-mentioned fractions increased with the increase in pulp, the same happening with the addition of urea. The internal marker with lowest variability among the internal markers was iADF, with mean values near 100%. Mean recovery of Cr2O3 was approximately 107%, but with lower variability among treatments. Inclusion of pineapple pulp in silage does not influence intake, while addition of urea only increases the intake of CP. The levels of pineapple pulp in silage with or without urea increase the digestibility of the silage. Indigestible acid detergent fiber is the marker with lowest variability of recovery, with mean recovery for the four silages used very close to 100%.

We conducted a continuous trial with 32 steers (Bos indicus × Bos taurus crosses) weighing from 100 to 450 kg to measure the aNDFom pool size in the ruminoreticulum Q N D F at slaughter, and two simultaneous 4 × 4 Latin Squares designs with some of the same animals of the continuous trial to measure the total digestibility of aNDFom T D N D F in the gastrointestinal tract. The diets were based on corn silage (CS) and soybean meal (SBM), and on CS and concentrate mixtures of SBM and ground yellow corn (GC). In the Latin square trial, the dry matter intake rates were set for an average daily gain equal to 0.6 kg/d. The treatments were dietary aNDFom intakes scaled to body weight B W at 3, 6, 9, and 12 g / kg · d combined with markers chromium (Cr) and europium (Eu) that labelled CS fibrous particles, and yttrium (Y) that labelled fibrous particles of the concentrate mixtures. The variables Q N D F and T D N D F were predicted by novel derivations of the models most often used to describe fecal excretion profiles of the markers Cr, Eu, and Y. We investigated the following compartmental models: the multicompartmental (MC), the single compartment (GN), and the two-compartment (GNG1) models. We used nonlinear mixed effects and generalized linear mixed-effects models to fit the compartmental models to and make inferences from the fecal marker profiles. In vitro digestion kinetics yielded the parameters that represent the potentially digestible, indigestible and digestion rates of feed aNDFom. All solutions of the GNG1 model violated a critical assumption for some treatment combinations and were deemed unacceptable and removed from the comparative analyses. The best-suited model to interpret fecal marker profiles, according to the information-theoretic (I-T) approach, was the MC model. The solutions for the GN model had less support for describing the fecal marker profiles than the MC model. In addition, several measures of model adequacy were used to empirically evaluate the model predictions against observed variables and revealed that, despite the choice based on I-T, both models MC and GN were equally capable of predicting the Q N D F and T D N D F variables with both accuracy and precision.

Use of acute-phase proteins (APPs) for assessment of health and disease in animals has increased greatly within the last decade. The objective was to determine the normal concentration of APPs in the serum and cerebrospinal fluid (CSF) of healthy cattle by polyacrylamide gel electrophoresis. Fifty crossbred animals (350±70kg of BW and 18±1.2 months of age), 25 heifers and 25 steers were used. CSF samples were collected from atlanto-occipital (AO) site and blood samples were obtained from the jugular vein. CSF and serum protein electrophoresis were performed by means of sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Thirty-seven proteins with molecular weights ranging from 7 and 37kDa were identified in CSF of all animals. These eight were nominally identified with immunoglobulin A and G, celuloplasmin, transferrin, albumin, α1-antitripsin, acidic glycoprotein, and haptoglobin. All protein fractions in CSF did not differ between heifers and steers. In sera, 34 proteins with molecular weights between 7 and 244kDa were identified in heifers and steers. Similar proteins were nominally identified in the sera, but only the CSF presented α1-antitripsin. The serum values of acidic glycoprotein and immunoglobulin G were significantly higher in steers compared with heifers. In conclusion, measurement of CSF acute phase protein concentrations can be useful in diagnosing and monitoring the progression of bovine neurological diseases, perhaps even to guide therapeutic procedures. The CSF electrophoretic profile of healthy cattle does not change depending on gender. RESUMO: O uso de proteínas de fase aguda (PFAs) para a avaliação da saúde e da doença em animais de produção tem aumentado consideravelmente na última década. O objetivo deste estudo foi determinar a concentração normal de PAFs no soro e no líquido cefalorraquidiano (LCR) de bovinos sadios por meio da eletroforese em gel de poliacrilamida. Foram avaliados cinquenta animais mestiços (350±70kg de PV e 18±1,2 meses de idade), 25 novilhas e 25 novilhos. As amostras de LCR foram colhidas no espaço atlanto-occipital (AO) e as amostras de sangue obtidas da veia jugular. As PAFs do soro e do LCR foram determinadas através da eletroforese em gel poliacrilamida. Trinta e sete proteínas com pesos moleculares que variaram entre 7 e 37kDa foram identificadas no LCR de todos os animais, independente do sexo. Estas oito proteínas foram nominalmente identificadas como imunoglobulina A e G, ceruloplasmina, transferrina, albumina, α1-antitripsina, glicoproteína ácida, e haptoglobina. As frações de proteínas presentes no LCR não diferiram entre novilhas e novilhos. No soro de machos e fêmeas, 34 proteínas com pesos moleculares entre 7 e 244 kDa foram identificadas. As proteínas do soro foram similarmente identificadas, entretanto a α1-antitripsina foi identificada somente no LCR. Os valores séricos de glicoproteína ácida e imunoglobulina G foram significativamente mais elevados nas novilhas em comparação aos novilhos. Em conclusão, a determinação das concentrações de proteínas de fase aguda presentes do LCR pode ser útil no diagnóstico e monitoramento da progressão de doenças neurológicas bovinas, talvez possa ainda direcionar procedimentos terapêuticos. O perfil eletroforético do LCR de bovinos hígidos não se altera em função do sexo.

We studied the ontogenetic growth of goat wethers (castrated male goats) of the Saanen and Swiss Alpine breeds based on a large range of intraspecific body mass (BM). The body parts and the chemical constituents of the empty body were described by the allometric function by using BM and the empty body mass (EBM) as the predictors for morphological traits and chemical composition, respectively. We fitted the allometric scaling function by applying the SAS NLMIXED procedure, but to evaluate assumptions regarding variances in morphological and compositional traits, we combined the scaling function with homoscedastic (MOD1), and the heteroscedastic exponential (MOD2) and power-of-the-mean (MOD3) variance functions. We also predicted the ontogenetic growth by using the traditional log-log transformation and back-transformed results into the arithmetic scale (MOD4). We obtained predictions from MOD4 in the arithmetic scale by a two-step process, and evaluated MOD1, MOD2 and MOD3 by a model selection framework, and compared MOD4 with MOD1, MOD2 and MOD3 based on goodness-of-fit measures. Based on information criteria for model selection, heterogeneous variance functions were more likely to describe 10 over 36 traits with a low level of model selection uncertainty. One trait was predicted by averaging the MOD1 and MOD2 variance functions; and nine traits were better described by averaging the MOD2 and MOD3 variance functions. The predictions for other 16 traits were averaged from MOD1, MOD2 and MOD3. However, MOD4 better described 11 traits according to the goodness-of-fit measures. Depending on the variable being analyzed, the body parts and the chemical amounts exhibited the three types of allometric behavior with respect to BM and EBM, that is, positive, negative and isometric ontogenetic growth. Reference BMs, that is, 20, 27, 35 and 45 kg, were used to compute the net protein and energy requirements based on the first derivative of the scaling function, and the results were presented in reference to the EBM and EBM0.75. Both the net protein and energy requirements scaled to EBM0.75 increased from 20 to 45 kg of BM.

The objective of this study was to evaluate the nutritive value of passion fruit by-product for cattle, contrasting the results with those found with sorghum silage. Four treatments were then constituted, comprising the combinations of the two roughages and the two levels of supplementation (with or without), in a completely randomized design with four animals per treatment. The considered variables included: feed intake, digestibility coefficients of the diets, and live weight gain of the animals. The experimental period lasted 70 days, preceded by a standardization period of 30 days. Chromium oxide was utilized to estimate the fecal output, in the digestibility trial. Treatments were compared by means of three orthogonal contrasts: between the two roughages and between the two concentrate levels within each roughage. Animals fed passion fruit by-product showed higher feed intake (total, per 100 kg of live weight (TLW), and per unit metabolic size) and had higher TLW gain than those fed sorghum silage (1.304 kg vs. 0.134 kg). The coefficients of apparent digestibility of dry matter (DM), organic matter (OM), and crude protein (CP) and the digestibility coefficient of neutral detergent fiber from passion fruit by-product were high, and much higher than those from sorghum silage. The concentrate supplement did not improve the TLW gain of animals fed passion fruit by-product and had a limiting effect on the digestibility coefficients of the diet. The concentrate supplement had a positive associative effect on intake and digestibility coefficients of DM, OM, and CP from sorghum silage. The by-product of fresh passion fruit is an excellent food for growing cattle as it provides high intake levels and weight gains, even when supplied as the only feed.

SUMMARYThe goal of the present study was to characterize the growth of body parts and composition of the growing empty body to infer how these aspects relate to the long-term growth of goat wethers from dairy breeds. Animals were slaughtered at several ages from birth to maturity (≅900 days old). All body parts were weighed and sampled to determine chemical constituent dry matter, crude protein, crude fat, ash and specific energy. The monomolecular (Brody), Gompertz, and Richards models, a biphasic model formed by the combined Brody and Gompertz functions, and a simple linear model were fitted to the growth profiles with different variance functions and were all evaluated using likelihood-information criteria. The effect of breed (genotype) was accounted for in all models but the resulting models were not more likely than the models without the breed effect. Remarkable differences were observed regarding inflection points, growth rates and trends for all body parts and chemical constituents of the body. The biphasic model did not supplant the monomolecular, Gompertz, Richards or the linear model in terms of likelihood-information criteria. Therefore, body parts and chemical constituents of the empty body presented monomolecular, sigmoid and linear time-trends. The growth profiles of fat, protein and energy of the empty body did not scale isometrically with the empty body proper. In addition, the variance was heteroscedastic along the time scale and was better represented by both an exponential variance over time or by a power function of the mean.

The aim of this study was to compare genomic selection methodologies using a linear mixed model and the Cox survival model. We used data from an F2 population of pigs, in which the response variable was the time in days from birth to the culling of the animal and the covariates were 238 markers [237 single nucleotide polymorphism (SNP) plus the halothane gene]. The data were corrected for fixed effects, and the accuracy of the method was determined based on the correlation of the ranks of predicted genomic breeding values (GBVs) in both models with the corrected phenotypic values. The analysis was repeated with a subset of SNP markers with largest absolute effects. The results were in agreement with the GBV prediction and the estimation of marker effects for both models for uncensored data and for normality. However, when considering censored data, the Cox model with a normal random effect (S1) was more appropriate. Since there was no agreement between the linear mixed model and the imputed data (L2) for the prediction of genomic values and the estimation of marker effects, the model S1 was considered superior as it took into account the latent variable and the censored data. Marker selection increased correlations between the ranks of predicted GBVs by the linear and Cox frailty models and the corrected phenotypic values, and 120 markers were required to increase the predictive ability for the characteristic analyzed.

The goal of the present study was to evaluate different mathematical models to describe the growth profiles of growing male kids. The kids used in the present study came from two experimental sets: one set of Alpine wethers (castrated at 15 days of age) and another set of Saanen kids. The variables measured in the first set were live weight (W), empty body weight (EBW), carcass weight, organs, empty gastrointestinal tract (GIT), skin, abdominal fat, trimmed cuts, blood, fresh GIT contents, and ruminoreticular fresh, dry matter, neutral detergent fiber, and lignin content at birth and at 15, 90, 135, 210, 270, and 365 days of age. The second set provided W and EBW of Saanen kids measured at 7, 37, 67, 142, and 195 days of age. The models tested were the monomolecular or Brody equation; the Gompertz, Richards, and generalized Michaelis–Menten models of sigmoid growth; and combinations of monomolecular and sigmoid models, forming biphasic models. In addition, four types of variance functions (covariance) were tested, namely, homogeneous, exponential, asymptotic, and power of the mean scaling function for each model. The model selection was based on the Akaike information criterion and its derived likelihood measures. The sigmoid simple models better described the time profiles, and the Gompertz model associated with homogeneous and scaled variances was the best choice for 57.1% of the growth profiles, most likely because of the ill-defined asymptotic phase; the biphasic models presented a lower likelihood probability of support. Nevertheless, the Brody–Gompertz and Brody-exponential growth biphasic models presented reasonable fits to certain variables, such as W, EBW, and carcass from both datasets. Therefore, despite the greater likelihood of the traditional growth functions, the biphasic models are promising for the description of the inflection points observed during the suckling-weaning and post-weaning phases of the goat kids’ growth profiles.

Sour passion fruit is an economically important tropical fruit crop with little explored genetic potential. This study aimed to provide breeders with essential estimates of genomic breeding values in economically important traits in passion fruit, using Bayesian models which may contribute to the implementation of Genomic Selection and develop new strategies for the continuity of sour passion fruit breeding programs. For this, the following Bayesian models were tested using 183 polymorphic marks: Bayesian Ridge regression, Bayes A, Bayes B, Bayes B2, Bayes Cπ and Bayesian Lasso for estimation of genomic breeding values. To achieve this, ninety-five full-sib progenies derived from the third cycle of recurrent selection of the sour passion fruit (Passiflora edulis Sims.) at Universidade Estadual do Norte Fluminense Darcy Ribeiro—UENF were used and eight fruit yield (number of fruit, total yield, mean fruit weight, fruit length, fruit width) and quality(percent pulp, skin thickness, soluble solids) traits were assessed. The Bayes Cπ (smaller deviance information criterion) yield the best genetic predictions for almost all traits. Genetic correlations in this study indicate that the number of fruit can be used as a proxy for yield. The values of genomic heritability obtained were high and ranged from 0.62 to 0.76 and predict accuracy ranged from 0.55 to 0.75, so we can to speculate that the use of two replicates in the present study was an adequate amount to obtain phenotypic mean, which was used to adjust the genomic prediction model.

Genome association analyses have been successful in identifying quantitative trait loci (QTLs) for pig body weights measured at a single age. However, when considering the whole weight trajectories over time in the context of genome association analyses, it is important to look at the markers that affect growth curve parameters. The easiest way to consider them is via the two-step method, in which the growth curve parameters and marker effects are estimated separately, thereby resulting in a reduction of the statistical power and the precision of estimates. One efficient solution is to adopt nonlinear mixed models (NMM), which enables a joint modeling of the individual growth curves and marker effects. Our aim was to propose a genome association analysis for growth curves in pigs based on NMM as well as to compare it with the traditional two-step method. In addition, we also aimed to identify the nearest candidate genes related to significant SNP (single nucleotide polymorphism) markers. The NMM presented a higher number of significant SNPs for adult weight (A) and maturity rate (K), and provided a direct way to test SNP significance simultaneously for both the A and K parameters. Furthermore, all significant SNPs from the two-step method were also reported in the NMM analysis. The ontology of the three candidate genes (SH3BGRL2, MAPK14, and MYL9) derived from significant SNPs (simultaneously affecting A and K) allows us to make inferences with regards to their contribution to the pig growth process in the population studied.

A nutritional analysis of Tanzania grass (Megathyrsus maximus Jacquin cv. Tanzânia was conducted. Pasture was managed in a rotational grazing system with a 30-day resting period, three days of paddock occupation and two grazing cycles. Ten Holstein × Zebu crossbred cows were kept within a 2-ha area divided into 11 paddocks ha-1. Cows were fed 2 kg of corn meal daily and performance was evaluated by weighing the animals every 14 days and by recording milk production twice a day. Nutritional composition of the Tanzania grass was determined from forage (extrusa) samples collected by esophageal fistulae from two animals. The nutritive value of Tanzania grass was estimated according to a modification of the CNCPS evaluation model. Tanzania grass supplemented with 2 kg of corn meal supplied 33.2% more net energy for lactation than required by the animals to produce 13.7 kg of milk day-1. Nevertheless, the amount of metabolizable protein met the daily protein requirement of the animals. Although the model used in the study requires adjustments, Tanzania grass has the potential to produce milk in a rotational grazing system.

The goals of this study were to evaluate the ability of a nonlinear optimization tool to provide solutions for maintaining consistent qualities of diets irrespective of the plane of nutrition (L) and to evaluate the effect of the plane of nutrition on intake and digestibility of dry matter (DM), organic matter (OM), crude protein (CP), crude fat (CF), non fibrous carbohydrates (NFC), neutral detergent fiber (NDF), and metabolizability (qm) of diets using sheep as a generalized experimental model. Eight wethers were randomly assigned to two balanced four-treatment Latin squares conducted simultaneously with four diets providing nutritional levels that were multiples of maintenance levels (ME=Mm; 1.5Mm; 2Mm; and 2.5Mm, where ME is the metabolizable energy intake, and Mm is the metabolizable energy intake for maintenance). The ME, Mm, metabolizable protein (MP) and NDF of the diet were subjected to nonlinear constraints; the model was considered a general nonlinear programming problem and solved using Microsoft Excel Solver® with Newton's method of resolution. The intake of nutrients, digestible nutrients, digestible energy (DE) and the amounts of feces and urine produced daily were measured and analyzed statistically by fitting a linear mixed model. The corrected metabolizability (qm') and plane of nutrition (Lc) were obtained on the basis of the digestible, urinary, and simulated methane losses. The trends of some variables were reanalyzed by regressing observed values against Lc. All measured variables were affected by L. The intakes of DM and OM increased in an asymptotic fashion as Lc increased, whereas the intake of NDF increased linearly as Lc increased. At levels immediately below maintenance, observed values were approximately constant. Digestible amounts of OM, DE, CF, and CP consumed increased linearly at levels above maintenance, whereas the digestible amounts of total carbohydrates, neutral detergent solubles, and ashes increased in an asymptotic fashion. Under conditions of controlled feeding, the nonlinear optimization tool yielded dietary solutions with a nearly constant metabolizability in which the rate of increase in crude protein, digestible crude protein, and digestible energy intakes remained constant as the plane of nutrition increased.

Recently, there is an increasing interest on semi- and non-parametric methods for genome-enabled prediction, among which the Bayesian regularized artificial neural networks (BRANN) stand. We aimed to evaluate the predictive performance of BRANN and to exploit SNP effects and heritability estimates using two different approaches (relative importance-RI, and relative contribution-RC). Additionally, we aimed also to compare BRANN with the traditional RR-BLUP and BLASSO by using simulated datasets. The simplest BRANN (net1), RR-BLUP and BLASSO methods outperformed other more parameterized BRANN (net2, net3, … net6) in terms of predictive ability. For both simulated traits (Y1 and Y2) the net1 provided the best h2 estimates (0.33 for both, being the true h2=0.35), whereas RR-BLUP (0.18 and 0.22 for Y1 and Y2, respectively) and BLASSO (0.20 and 0.26 for Y1 and Y2, respectively) underestimated h2. The marker effects estimated from net1 (using RI and RC approaches) and RR-BLUP were similar, but the shrinkage strength was remarkable for BLASSO on both traits. For Y1, the correlation between the true fifty QTL effects and the effects estimated for the SNPs located in the same QTL positions were 0.61, 0.60, 0.60 and 0.55, for RI, RC, RR-BLUP and BLASSO; and for Y2, these correlations were 0.81, 0.81, 0.81 and 0.71, respectively. In summary, we believe that estimates of SNP effects are promising quantitative tools to bring discussions on chromosome regions contributing most effectively to the phenotype expression when using ANN for genomic predictions.

The objective of this study was to simulate total dry matter intake and cost of diets optimized by nonlinear programming to meet the nutritional requirements of dairy does and growing doelings. The mathematical model was programmed in a Microsoft Excel(r) spreadsheet. Increasing values of body mass and average daily weight gain for growing doelings and increasing body mass values and milk yield for dairy does were used as inputs for optimizations. Three objective functions were considered: minimization of the dietary cost, dry matter intake maximization, and maximization of the efficiency of use of the ingested crude protein. To solve the proposed problems we used the Excel(r) Solver(r) algorithm. The Excel(r) Solver(r) was able to balance diets containing different objective functions and provided different spaces of feasible solutions. The best solutions are obtained by least-cost formulations; the other two objective functions, namely maximize dry matter intake and maximize crude protein use, do not produce favorable diets in terms of costs.

We propose and evaluate a novel approach for forecasting gene expression over non-observed times in longitudinal trials under a Bayesian viewpoint. One of the aims is to cluster genes that share similar expression patterns over time and then use this similarity to predict relative expression at time points of interest. Expression values of 106 genes expressed during the cell cycle of Saccharomyces cerevisiae were used and genes were partitioned into five distinct clusters of sizes 33, 32, 21, 16, and 4. After removing the last observed time point, the agreements of signals (upregulated or downregulated) considering the predicted expression level were 72.7, 81.3, 76.2, 68.8, and 50.0%, respectively, for each cluster. The percentage of credibility intervals that contained the true values of gene expression for a future time was ~90%. The methodology performed well, providing a valid forecast of gene expression values by fitting an autoregressive panel data model. This approach is easily implemented with other time-series models and when Poisson and negative binomial probability distributions are assumed for the gene expression data.

A significant contribution of molecular genetics is the direct use of DNA information to identify genetically superior individuals. With this approach, genome-wide selection (GWS) can be used for this purpose. GWS consists of analyzing a large number of single nucleotide polymorphism markers widely distributed in the genome; however, because the number of markers is much larger than the number of genotyped individuals, and such markers are highly correlated, special statistical methods are widely required. Among these methods, independent component regression, principal component regression, partial least squares, and partial principal components stand out. Thus, the aim of this study was to propose an application of the methods of dimensionality reduction to GWS of carcass traits in an F2 (Piau x commercial line) pig population. The results show similarities between the principal and the independent component methods and provided the most accurate genomic breeding estimates for most carcass traits in pigs.

The basic problemwith the approach we adopted in the paper of Jardim et al. (2013) is that we found the denominator of the reported ratio Eq. (17)/Eq. (18) by assuming Lc 1⁄4ME=Mm, Mm 1⁄4 ðFHPþAÞ=km, and km 1⁄4 0:35ME=GEþ0:503. Nonetheless, the metabolizability of the diet (q1⁄4ME=GE) is lower than the metabolizability of the diet at maintenance, namely qm, 8 Lc41 (Blaxter and Boyne, 1978). We maintained terms and units here accordingly. In the paper of Jardim et al. (2013), we assumed the gross energy intake as GE1⁄4 18:8F (MJ/day). Therefore, our km values were biased because our qm values were also biased to some extent. By definition, qm is measured at maintenance (Blaxter and Boyne, 1978): qm 1⁄4MEm=GEm. MEm and GEm are the respective metabolizable and gross energy intake rates at maintenance, and MEm meets Mm, i.e., MEm=Mm 1⁄4 1. Nonetheless, let us define the dry matter intake measured at maintenance as Fm (kg/day), consequently, GEm 1⁄4 18:8Fm. If Mm 1⁄4ME=Lc, Mm 1⁄4 ðFHPþAÞ=km, km 1⁄4 0:35MEm=GEmþ0:503, and Mm 1⁄4MEm, then after algebraically isolating ME and taking only its positive root and simplifying constants, we have a new Eq. (18) based on the correct definition of qm: ME1⁄4 26:9Fmð 0:503Lcþð0:253Lc þ1:4Lc ðFHPþAÞ=ð18:8FmÞÞÞ: ð18Þ