Natural Growth Promoters Replacing Traditional Growth Promoters in Diets for Light Replacement Pullets: A Systematic Approach

The effect of using natural growth promoters (NGP) to replace traditional antimicrobials on performance, biometry of digestive and reproductive organs, sexual maturity and bone characteristics of replacement pullets was evaluated; and the relationship between these variables according to the diets was verified. Eight-week-old birds were randomly assigned to a completely randomized design and fed different diets: negative control (without growth promoters); positive control - conventional growth promoter; organic acids (OA); symbiotic (S); essential oil (EO); OA + S; and EO + S. The performance, relative weight of digestive and reproductive organs and length intestines, height and crest length, sternum length, bone quality and sexual maturity of birds were similar (p>0.05) between treatments. The heat map combined with cluster analysis showed a uniform static pattern with the formation of three horizontal groups formed by the treatments: 1) negative control, S and OA + S; 2) positive control and OE and 3) OA and OE + S. A null relationship between the treatments and the variables under study was observed. The principal components analysis revealed an association of variables in three components with 60.55% of variation. NGP can replace traditional promoters, as they do not interfere with performance, biometrics or sexual maturity. Height and length are predictive variables for the development of reproductive organs, especially the oviduct. A similarity was identified through multivariate techniques between symbiotic and organic + symbiotic acids; positive control and essential oils; and organic and symbiotic acids + essential oils.(AU)

Using canonical correlation analysis to understand the rumen biohydrogenation patterns of linoleic and alpha-linolenic acids in the rumen fluid of bovines

The objective of this study was to determine the multivariate relationship among linoleic acid, alpha-linolenic acid, and their main rumen biohydrogenation (BH) intermediates and products in bovine rumen fluid using canonical correlation analysis (CCA). A dataset consisting of 1177 observations generated by 107 in vitro rumen incubation systems of pure and mixed linoleic acid (18:2-c9, c12) and alpha-linolenic acid (18:3-c9, c12, c15) was gathered. Two canonical variates were defined: A: composed of the nine main BH intermediates and products (18:2-c9, t11; 18:2-t11, c15; 18:1-t11; 18:1-t9; 18:1-t6; 18:1-c11; 18:1-c6; 18:1-c9; 18:0) of 18:2-c9, c12 and 18:3-c9, c12, c15 and B: composed of 18:2-c9, c12 and 18:3-c9, c12, c15. Two canonical functions between A and B with significant canonical correlations (R1=0.990 and R2=0.738; p <0.01) were obtained. However, only the first function was selected for CCA. Exploration of canonical loadings for first function, revealed the following quantitative significance (absolute value) order for fatty acids (FA) within their respective canonical variates: A: 18:0(0.958)>18:1-t9(0.837)>18:1-c11(0.835)>18:1-c6(0.824)>18:1-t11(0.747)>18:1-c9(0.738)>18:1-t6(0.415)>18:2-t11, c15(0.387)> 18:2-c9, t11(0.239); B: 18:2-c9, c12(0.667)>18:3-c9, c12, c15(0.488). The CCA showed that 18:2-c9, c12 has a greater contribution than that of 18:3-c9, c12, c15 on the production of the aforementioned BH intermediates, in which 18:0, as well as the groups of 18:1 cis and trans-FA were mainly affected.(AU)

Characterization of dystocia in a herd of Holstein dairy cows in Brazil / Caracterização da distocia em um rebanho de vacas da raça Holandesa no Brasil

The objective of this study was to characterize calvings with low and high difficulty based on the productive and reproductive performance of dairy cows. Calvings were grouped in no calving assistance, calving with low assistance, and calving with high assistance. The original data set comprised 1,902 calving records obtained from a large dairy farm in Southeast Brazil. Factor analysis was applied using the SAS® Studio 3.8 statistical program through the factor procedure, considering the Multivariate Analysis category. Milk fat (0.92-0.79) and total solids (0.91-0.80) were strongly correlated with Factor 1. Calving interval (0.87- 0.68) and the number of AI (artificial inseminations) per conception (0.87-0.71) showed high correlations with Factor 2. Milk yield (0.84-0.76) and accumulated milk yield (0.84-0.77) were strongly correlated with Factor 3. Based on the results, we conclude that the three calving scenarios were characterized by well-defined and independent factors. Cows which required a high assistance at calving showed a lower variance explained by the model for milk fat and total solids contents, calving interval, and the number of AIs per conception.

O objetivo deste estudo foi caracterizar os partos com leve ou severa dificuldade e diferenciá-los com base no desempenho produtivo e reprodutivo de vacas leiteiras. Os partos foram agrupados em partos sem assistência, partos com baixa assistência e partos com elevada assistência. O banco de dados original continha 1902 registro de partos que foram obtidos de uma grande fazenda comercial localizada no Sudeste do Brasil. A análise fatorial foi aplicada através do programa estatístico SAS® Studio 3.8 por meio de procedimento fatorial, considerando a categoria de análise multivariada. Os teores de gordura do leite (0,92- 0,79) e de sólidos totais (0,91-0,80) foram altamente correlacionados com o fator 1. Intervalo entre partos (0,87-0,68) e número de IA (inseminações artificiais) por concepção (0,87-0,71) apresentaram alta correlação com o fator 2. Produção de leite (0,84-0,76) e produção acumulada de leite (0,84-0,77) foram altamente correlacionados com o fator 3. Baseados nos resultados, é possível concluir que as três situações de parto foram caracterizadas por fatores independentes e bem definidos. Vacas que necessitaram de alta assistência ao parto apresentaram menor variância explicada pelo modelo para teores de gordura e sólidos totais do leite, intervalo entre partos e número de IA por concepção.

Seasonal analysis of food items and feeding habits of endangered riverine catfish Rita rita (Hamilton, 1822) / Análise sazonal de itens e hábitos alimentares de bagres ribeirinhos Rita rita (Hamilton, 1822) ameaçados de extinção

This investigation presents the food and feeding activity of and endangered riverine catfish Rita rita, during February 2017-January 2018. A total of 225 fish individuals was analyzed for stomach contents by characterizing the dominant food items and morphometric features. The results divulged ten major food items consumed, preferably fish scales and eggs, teleost fishes, copepods, cladocerans, rotifers, and mollusks. Total length and body weight of fish varied between 9-34 cm (20.53 ± 6.90 cm) and 10-400 g (9125.94 ± 102.07 g), respectively. The index of relative importance (IRI%) showed the importance of rotifers over the other food items. Morisita's index of diet overlap indicated seasonal variations in catfish diets with summer and monsoon displaying the least overlap, while maximum overlap during monsoon and winter seasons. The non-metric multidimensional scaling (nMDS) indicated the close association between the food items available during summer and winter seasons with a significant difference among the seasons (ANOSIM, R = 0.638, P = 0.013). Levin’s niche breadth index arranged in the order of 0.88>0.81>0.78>0.63>0.43 for the size classes of V, IV, III, II and I, respectively. The PCA explained 95.39% of the total variance among the food items and fish size groups. Small-sized fish individuals displayed a greater correlation with food items suitable for their mouth size. In conclusion, the variety and frequency of food items recorded indicated considerable feeding plasticity and opportunistic feeding behavior with a shift from carnivorous to omnivorous feeding nature. This study could render useful information on the food and feeding habits of R. rita and provide background for preparing its diet for future aquaculture practices.

Esta investigação apresenta a alimentação e a atividade alimentar de bagres ribeirinhos Rita rita ameaçados de extinção, no período de fevereiro de 2017 a janeiro de 2018. Um total de 225 peixes foi analisado quanto ao conteúdo do estômago, caracterizando os itens alimentares dominantes e as características morfométricas. Os resultados apresentaram dez principais itens alimentares consumidos, preferencialmente escamas e ovos de peixes, teleósteos, copépodes, cladóceros, rotíferos e moluscos. O comprimento total e o peso corporal dos peixes variaram entre 9-34 cm (20,53 ± 6,90 cm) e 10-400 g (9125,94 ± 102,07 g), respectivamente. O índice de importância relativa (IRI%) mostrou a importância dos rotíferos sobre os demais itens alimentares. O índice de sobreposição de dieta de Morisita indicou variações sazonais nas dietas de bagres no verão e nas monções, exibindo a menor sobreposição, enquanto a sobreposição máxima ocorreu durante as estações das monções e do inverno. A escala multidimensional não métrica (nMDS) indicou a estreita associação entre os itens alimentares disponíveis durante o verão e o inverno, com uma diferença significativa entre as estações (ANOSIM, R = 0,638, P = 0,013). O índice de amplitude de nicho de Levin foi organizado na ordem de 0,88 > 0,81 > 0,78 > 0,63 > 0,43 para as classes de tamanho de V, IV, III, II e I, respectivamente. O PCA explicou 95,39% da variação total entre os itens alimentares e os grupos de tamanho de peixes. Peixes de pequeno porte apresentaram maior correlação com itens alimentares adequados ao tamanho da boca. Em conclusão, a variedade e a frequência dos itens alimentares registrados indicaram plasticidade alimentar considerável e comportamento alimentar oportunista, com uma mudança da natureza carnívora para onívora. Este estudo pode fornecer informações úteis sobre os hábitos alimentares e de alimentação de R. rita e apresentar subsídios para a preparação de sua dieta em futuras práticas de aquicultura.

Seasonal analysis of food items and feeding habits of endangered riverine catfish Rita rita (Hamilton, 1822)

Abstract This investigation presents the food and feeding activity of and endangered riverine catfish Rita rita, during February 2017-January 2018. A total of 225 fish individuals was analyzed for stomach contents by characterizing the dominant food items and morphometric features. The results divulged ten major food items consumed, preferably fish scales and eggs, teleost fishes, copepods, cladocerans, rotifers, and mollusks. Total length and body weight of fish varied between 9-34 cm (20.53 ± 6.90 cm) and 10-400 g (9125.94 ± 102.07 g), respectively. The index of relative importance (IRI%) showed the importance of rotifers over the other food items. Morisitas index of diet overlap indicated seasonal variations in catfish diets with summer and monsoon displaying the least overlap, while maximum overlap during monsoon and winter seasons. The non-metric multidimensional scaling (nMDS) indicated the close association between the food items available during summer and winter seasons with a significant difference among the seasons (ANOSIM, R = 0.638, P = 0.013). Levins niche breadth index arranged in the order of 0.88>0.81>0.78>0.63>0.43 for the size classes of V, IV, III, II and I, respectively. The PCA explained 95.39% of the total variance among the food items and fish size groups. Small-sized fish individuals displayed a greater correlation with food items suitable for their mouth size. In conclusion, the variety and frequency of food items recorded indicated considerable feeding plasticity and opportunistic feeding behavior with a shift from carnivorous to omnivorous feeding nature. This study could render useful information on the food and feeding habits of R. rita and provide background for preparing its diet for future aquaculture practices.

Resumo Esta investigação apresenta a alimentação e a atividade alimentar de bagres ribeirinhos Rita rita ameaçados de extinção, no período de fevereiro de 2017 a janeiro de 2018. Um total de 225 peixes foi analisado quanto ao conteúdo do estômago, caracterizando os itens alimentares dominantes e as características morfométricas. Os resultados apresentaram dez principais itens alimentares consumidos, preferencialmente escamas e ovos de peixes, teleósteos, copépodes, cladóceros, rotíferos e moluscos. O comprimento total e o peso corporal dos peixes variaram entre 9-34 cm (20,53 ± 6,90 cm) e 10-400 g (9125,94 ± 102,07 g), respectivamente. O índice de importância relativa (IRI%) mostrou a importância dos rotíferos sobre os demais itens alimentares. O índice de sobreposição de dieta de Morisita indicou variações sazonais nas dietas de bagres no verão e nas monções, exibindo a menor sobreposição, enquanto a sobreposição máxima ocorreu durante as estações das monções e do inverno. A escala multidimensional não métrica (nMDS) indicou a estreita associação entre os itens alimentares disponíveis durante o verão e o inverno, com uma diferença significativa entre as estações (ANOSIM, R = 0,638, P = 0,013). O índice de amplitude de nicho de Levin foi organizado na ordem de 0,88 > 0,81 > 0,78 > 0,63 > 0,43 para as classes de tamanho de V, IV, III, II e I, respectivamente. O PCA explicou 95,39% da variação total entre os itens alimentares e os grupos de tamanho de peixes. Peixes de pequeno porte apresentaram maior correlação com itens alimentares adequados ao tamanho da boca. Em conclusão, a variedade e a frequência dos itens alimentares registrados indicaram plasticidade alimentar considerável e comportamento alimentar oportunista, com uma mudança da natureza carnívora para onívora. Este estudo pode fornecer informações úteis sobre os hábitos alimentares e de alimentação de R. rita e apresentar subsídios para a preparação de sua dieta em futuras práticas de aquicultura.

In vitro conservation of 'Florida Rough' lemon plants / Conservação in vitro de plantas de limoeiro 'Rugoso da Florida'

The establishment of minimum growth conditions is essential for in vitro germplasm conservation. Changes to the basic medium and carbon source concentrations are important factors for reducing plant growth in vitro. This study adjusted a protocol for the in vitro conservation of 'Florida Rough' lemon plants. Microcuttings (approximately 1 cm) from plants that were previously cultivated in vitro were inoculated into test tubes with 10 mL of woody plant medium (WPM) at different concentrations (1/1, 1/2 and 1/4) and supplemented with 0, 12.5, 25 and 50 g.L-1 of sucrose, solidified with 7 g.L-1 agar and adjusted to pH 5.8. The experiment was completely randomized in a 3 x 4 factorial design with 15 replications and was maintained under controlled conditions for 360 days. After this period the plant height in cm (PH), the plant dry mass in g (PDM) and the 21 numbers of green leaves (NGL), senescent leaves (NSL) and microcuttings (NM) were evaluated. The variables that best explained the observed behavior of the 'Florida Rough' lemon plants were NGL and PH, with values of 61.63 and 35.08%, respectively. The original concentration of the WPM with the addition of 25 g. L-1 of sucrose yielded the best 'Florida Rough' lemon plant growth reduction in vitro while maintaining the physiologically health of the plants.

O estabelecimento de condições de crescimento mínimo é fundamental para a conservação in vitro de germoplasma. Alterações nas concentrações do meio básico, na fonte de carbono, são fatores importantes na desaceleração do crescimento de plantas in vitro. Este trabalho teve como objetivo ajustar um protocolo de conservação in vitro de plantas do limoeiro 'Rugoso da Flórida'. Microestacas de plantas previamente cultivadas in vitro, com aproximadamente 1 cm, foram inoculadas em tubos de ensaio contendo 10 mL do meio de cultura WPM em diferentes concentrações (1/1, 1/2 e 1/4), suplementado com 0; 12,5; 25 e 50 g.L-1 de sacarose, solidificado com 7 g.L-1 de ágar e o pH ajustado em 5,8. O experimento foi instalado em delineamento inteiramente casualizado com 15 repetições, em esquema fatorial 3 x 4, e mantido sob condições controladas durante 360 dias. Após este período, foram avaliadas altura de planta em cm (AP), número de folhas verdes (NFV), número de folhas senescentes (NFS), número de microestacas (NM) e massa da planta seca em g (MPS). As variáveis que mais contribuíram para explicar a diferença existente no comportamento das plantas do limoeiro 'Rugoso da Flórida' no meio de cultura WPM foram NFV e AP com 61,63 e 35,08%, respectivamente. O meio de cultura WPM na sua concentração original com a adição de 25 g.L-1 de sacarose promoveu os melhores resultados na redução do crescimento das plantas in vitro do limoeiro 'Rugoso da Flórida', mantendo-as fisiologicamente sadias.

Seasonal analysis of food items and feeding habits of endangered riverine catfish Rita rita (Hamilton, 1822) / Análise sazonal de itens e hábitos alimentares de bagres ribeirinhos Rita rita (Hamilton, 1822) ameaçados de extinção

This investigation presents the food and feeding activity of and endangered riverine catfish Rita rita, during February 2017-January 2018. A total of 225 fish individuals was analyzed for stomach contents by characterizing the dominant food items and morphometric features. The results divulged ten major food items consumed, preferably fish scales and eggs, teleost fishes, copepods, cladocerans, rotifers, and mollusks. Total length and body weight of fish varied between 9-34 cm (20.53 ± 6.90 cm) and 10-400 g (9125.94 ± 102.07 g), respectively. The index of relative importance (IRI%) showed the importance of rotifers over the other food items. Morisita's index of diet overlap indicated seasonal variations in catfish diets with summer and monsoon displaying the least overlap, while maximum overlap during monsoon and winter seasons. The non-metric multidimensional scaling (nMDS) indicated the close association between the food items available during summer and winter seasons with a significant difference among the seasons (ANOSIM, R = 0.638, P = 0.013). Levins niche breadth index arranged in the order of 0.88>0.81>0.78>0.63>0.43 for the size classes of V, IV, III, II and I, respectively. The PCA explained 95.39% of the total variance among the food items and fish size groups. Small-sized fish individuals displayed a greater correlation with food items suitable for their mouth size. In conclusion, the variety and frequency of food items recorded indicated considerable feeding plasticity and opportunistic feeding behavior with a shift from carnivorous to omnivorous feeding nature. This study could render useful information on the food and feeding habits of R. rita and provide background for preparing its diet for future aquaculture practices.(AU)

Esta investigação apresenta a alimentação e a atividade alimentar de bagres ribeirinhos Rita rita ameaçados de extinção, no período de fevereiro de 2017 a janeiro de 2018. Um total de 225 peixes foi analisado quanto ao conteúdo do estômago, caracterizando os itens alimentares dominantes e as características morfométricas. Os resultados apresentaram dez principais itens alimentares consumidos, preferencialmente escamas e ovos de peixes, teleósteos, copépodes, cladóceros, rotíferos e moluscos. O comprimento total e o peso corporal dos peixes variaram entre 9-34 cm (20,53 ± 6,90 cm) e 10-400 g (9125,94 ± 102,07 g), respectivamente. O índice de importância relativa (IRI%) mostrou a importância dos rotíferos sobre os demais itens alimentares. O índice de sobreposição de dieta de Morisita indicou variações sazonais nas dietas de bagres no verão e nas monções, exibindo a menor sobreposição, enquanto a sobreposição máxima ocorreu durante as estações das monções e do inverno. A escala multidimensional não métrica (nMDS) indicou a estreita associação entre os itens alimentares disponíveis durante o verão e o inverno, com uma diferença significativa entre as estações (ANOSIM, R = 0,638, P = 0,013). O índice de amplitude de nicho de Levin foi organizado na ordem de 0,88 > 0,81 > 0,78 > 0,63 > 0,43 para as classes de tamanho de V, IV, III, II e I, respectivamente. O PCA explicou 95,39% da variação total entre os itens alimentares e os grupos de tamanho de peixes. Peixes de pequeno porte apresentaram maior correlação com itens alimentares adequados ao tamanho da boca. Em conclusão, a variedade e a frequência dos itens alimentares registrados indicaram plasticidade alimentar considerável e comportamento alimentar oportunista, com uma mudança da natureza carnívora para onívora. Este estudo pode fornecer informações úteis sobre os hábitos alimentares e de alimentação de R. rita e apresentar subsídios para a preparação de sua dieta em futuras práticas de aquicultura.(AU)

Seasonal analysis of food items and feeding habits of endangered riverine catfish Rita rita (Hamilton, 1822) / Análise sazonal de itens e hábitos alimentares de bagres ribeirinhos Rita rita (Hamilton, 1822) ameaçados de extinção

This investigation presents the food and feeding activity of and endangered riverine catfish Rita rita, during February 2017-January 2018. A total of 225 fish individuals was analyzed for stomach contents by characterizing the dominant food items and morphometric features. The results divulged ten major food items consumed, preferably fish scales and eggs, teleost fishes, copepods, cladocerans, rotifers, and mollusks. Total length and body weight of fish varied between 9-34 cm (20.53 ± 6.90 cm) and 10-400 g (9125.94 ± 102.07 g), respectively. The index of relative importance (IRI%) showed the importance of rotifers over the other food items. Morisita's index of diet overlap indicated seasonal variations in catfish diets with summer and monsoon displaying the least overlap, while maximum overlap during monsoon and winter seasons. The non-metric multidimensional scaling (nMDS) indicated the close association between the food items available during summer and winter seasons with a significant difference among the seasons (ANOSIM, R = 0.638, P = 0.013). Levin's niche breadth index arranged in the order of 0.88>0.81>0.78>0.63>0.43 for the size classes of V, IV, III, II and I, respectively. The PCA explained 95.39% of the total variance among the food items and fish size groups. Small-sized fish individuals displayed a greater correlation with food items suitable for their mouth size. In conclusion, the variety and frequency of food items recorded indicated considerable feeding plasticity and opportunistic feeding behavior with a shift from carnivorous to omnivorous feeding nature. This study could render useful information on the food and feeding habits of R. rita and provide background for preparing its diet for future aquaculture practices.

Esta investigação apresenta a alimentação e a atividade alimentar de bagres ribeirinhos Rita rita ameaçados de extinção, no período de fevereiro de 2017 a janeiro de 2018. Um total de 225 peixes foi analisado quanto ao conteúdo do estômago, caracterizando os itens alimentares dominantes e as características morfométricas. Os resultados apresentaram dez principais itens alimentares consumidos, preferencialmente escamas e ovos de peixes, teleósteos, copépodes, cladóceros, rotíferos e moluscos. O comprimento total e o peso corporal dos peixes variaram entre 9-34 cm (20,53 ± 6,90 cm) e 10-400 g (9125,94 ± 102,07 g), respectivamente. O índice de importância relativa (IRI%) mostrou a importância dos rotíferos sobre os demais itens alimentares. O índice de sobreposição de dieta de Morisita indicou variações sazonais nas dietas de bagres no verão e nas monções, exibindo a menor sobreposição, enquanto a sobreposição máxima ocorreu durante as estações das monções e do inverno. A escala multidimensional não métrica (nMDS) indicou a estreita associação entre os itens alimentares disponíveis durante o verão e o inverno, com uma diferença significativa entre as estações (ANOSIM, R = 0,638, P = 0,013). O índice de amplitude de nicho de Levin foi organizado na ordem de 0,88 > 0,81 > 0,78 > 0,63 > 0,43 para as classes de tamanho de V, IV, III, II e I, respectivamente. O PCA explicou 95,39% da variação total entre os itens alimentares e os grupos de tamanho de peixes. Peixes de pequeno porte apresentaram maior correlação com itens alimentares adequados ao tamanho da boca. Em conclusão, a variedade e a frequência dos itens alimentares registrados indicaram plasticidade alimentar considerável e comportamento alimentar oportunista, com uma mudança da natureza carnívora para onívora. Este estudo pode fornecer informações úteis sobre os hábitos alimentares e de alimentação de R. rita e apresentar subsídios para a preparação de sua dieta em futuras práticas de aquicultura.

Use of quali-quantitative feeding practices criteria in typology of smallholders' dairy production systems

This study aimed to typify smallholders' dairy systems using quali-quantitative measures of feeding practices and detect the main discriminatory elements identifying the systems. We collected data from 30 farms distributed in 10 municipalities in the eastern region of Rio Grande do Sul, Brazil, using a survey with semi-structured questions, in addition to bimonthly observations of milking and feeding practices. Multivariate analysis based on principal factors and cluster analysis were performed. Multiple linear regressions were made between the principal factors scores and variables of milk production and composition. Three principal factors with eigenvalues ≥1.0 explained 58.9% of the total variance. The original variables with the highest factor loading values were production scale and feeding practices involving greater quantities of byproducts; use of corn silage and sugarcane; and commercial and farm-made concentrate for principal factor 1, principal factor 2, and principal factor 3, respectively. Milk yield and concentrations of lactose and solids non-fat increased linearly with principal factor 1 and principal factor 3 but decreased linearly with principal factor 2. Observations were grouped into three clusters. Farm area and quantity of corn silage and byproducts were the most important variables to set the clusters. The use of quali-quantitative feeding practices criteria to characterize dairy systems is effective to identify the opportunities for improving milk production and composition. Whereas high inclusion of sugarcane as roughage was detrimental for milk production, moderate supply of concentrate and byproducts enhanced milk yield without compromising milk composition.

Multivariate modeling strategies to predict nutritional requirements of essential amino acids in semiheavy second-cycle hens

An experiment with 23 diets was performed to evaluate the effect of digestible lysine (Lys), digestible methionine + cysteine (Met+Cys), and digestible threonine (Thr) on egg production of H&N Brown second-cycle laying hens (SCLH) for 20 weeks (92-111 weeks of age) in cages under environmental conditions. Body weight (BW), feed intake (FI), feed conversion ratio (FCR), egg weight (EW), number of hen-housed eggs, and livability were also evaluated during the experiment. Diets were formulated from a central composite design that combined five levels of Lys, Met+Cys, and Thr ranging from 727 to 1159, 662 to 1055, and 552 to 882 mg/kg, respectively. Egg production (EP) data were evaluated through three different modeling strategies: egg production models, multivariate polynomial models, and artificial neural networks (ANN). A cascade-forward neural network with logsigmoid transfer function was selected as the best model according to goodness-offit statistics in both identification and validation data. One of the best scenarios for EP of H&N Brown SCLH under specific outdoor conditions was established at Lys, Met+Cys, and Thr levels of 1138, 1031, and 717 mg/hen·day, respectively. The ANN model may be an appropriate tool to study and predict EP of H&N Brown SCLH based on the combination of three different levels of essential digestible amino acids. The strategies included in this work may contribute to improving poultry performance based on modeling techniques to study other production parameters in terms of different nutritional requirements and productive conditions.

Cost reduction and quality enhancement in passion fruit seedlings using alternative substrate / Redução de custo e aumento da qualidade de mudas de maracujá azedo usando substrato alternativo

Obtaining vigorous, quality seedlings is a complex task because it involves multiple physical, chemical and biological factors, with the substrate being a fundamental of this process. Therefore, this study proposes to evaluate different formulations of substrate mixtures and identify which provides better emergence vigor and shoot and root growth in passion fruit (Passiflora edulis Sims). The experiment was laid out in a completely randomized design consisting of 23 substrates with different proportions of Vivatto® and Osmocote®, washed sand, soil, fine coal, coarse coal, enriched hydrogel and enriched vermiculite, with and without the addition of NPK, which were distributed into four replications of four plants per plot. To enrich the hydrogel and vermiculite, foliar fertilizer was used. Emergence vigor was evaluated throughout the seedling emergence period and seedling growth parameters were observed at 60 days after sowing. The data were subjected to multivariate analysis and the groups formed were subjected to analysis of variance. Based on principal component analysis (PCA), four groups were identified. The group composed only of soil + coarse coal and enriched hydrogel (2:2:1) was considered the best treatment, as it favored most of the vegetative growth and emergence vigor traits. Soil plus sand with the addition of NPK was not recommended to grow passion fruit seedlings in any of the proportions used, as there was no emergence.

A obtenção de mudas com qualidade e vigor é complexa, pois envolve múltiplos fatores físicos, químicos e biológicos sendo o substrato fundamental neste processo, assim, o objetivo deste trabalho foi avaliar diferentes formulações de substrato e identificar qual proporciona melhor vigor de emergência e crescimento de parte aérea e raízes de maracujá amarelo (Passiflora edulis Sims). O delineamento experimental foi inteiramente casualizado, composto por 23 substratos, em diferentes misturas de Vivatto®, Osmocote®, areia lavada, solo, resíduo de carvão fino, carvão grosso, hidrogel enriquecido e vermiculita enriquecida com adubo foliar, além de tratamentos com e sem adição de NPK, distribuídos em quatro repetições de quatro plantas por parcela. O vigor de emergência foi avaliado durante o período de emergência das plântulas e os parâmetros de crescimento das plântulas foram observados aos 60 dias após a semeadura. Os dados foram submetidos à análise multivariada e os grupos formados foram submetidos à análise de variância. Com base na análise de componentes principais (PCA), quatro grupos foram identificados. O grupo composto apenas de solo + carvão vegetal e hidrogel enriquecido (2:2:1), foi considerado o melhor tratamento, pois favoreceu a maioria das características de crescimento vegetativo e vigor de emergência. O solo mais a areia com a adição de NPK não foi recomendado para a produção de mudas de maracujá azedo em nenhuma das proporções utilizadas, pois não houve emergência.

Cost reduction and quality enhancement in passion fruit seedlings using alternative substrate / Redução de custo e aumento da qualidade de mudas de maracujá azedo usando substrato alternativo

Obtaining vigorous, quality seedlings is a complex task because it involves multiple physical, chemical and biological factors, with the substrate being a fundamental of this process. Therefore, this study proposes to evaluate different formulations of substrate mixtures and identify which provides better emergence vigor and shoot and root growth in passion fruit (Passiflora edulis Sims). The experiment was laid out in a completely randomized design consisting of 23 substrates with different proportions of Vivatto® and Osmocote®, washed sand, soil, fine coal, coarse coal, enriched hydrogel and enriched vermiculite, with and without the addition of NPK, which were distributed into four replications of four plants per plot. To enrich the hydrogel and vermiculite, foliar fertilizer was used. Emergence vigor was evaluated throughout the seedling emergence period and seedling growth parameters were observed at 60 days after sowing. The data were subjected to multivariate analysis and the groups formed were subjected to analysis of variance. Based on principal component analysis (PCA), four groups were identified. The group composed only of soil + coarse coal and enriched hydrogel (2:2:1) was considered the best treatment, as it favored most of the vegetative growth and emergence vigor traits. Soil plus sand with the addition of NPK was not recommended to grow passion fruit seedlings in any of the proportions used, as there was no emergence.(AU)

A obtenção de mudas com qualidade e vigor é complexa, pois envolve múltiplos fatores físicos, químicos e biológicos sendo o substrato fundamental neste processo, assim, o objetivo deste trabalho foi avaliar diferentes formulações de substrato e identificar qual proporciona melhor vigor de emergência e crescimento de parte aérea e raízes de maracujá amarelo (Passiflora edulis Sims). O delineamento experimental foi inteiramente casualizado, composto por 23 substratos, em diferentes misturas de Vivatto®, Osmocote®, areia lavada, solo, resíduo de carvão fino, carvão grosso, hidrogel enriquecido e vermiculita enriquecida com adubo foliar, além de tratamentos com e sem adição de NPK, distribuídos em quatro repetições de quatro plantas por parcela. O vigor de emergência foi avaliado durante o período de emergência das plântulas e os parâmetros de crescimento das plântulas foram observados aos 60 dias após a semeadura. Os dados foram submetidos à análise multivariada e os grupos formados foram submetidos à análise de variância. Com base na análise de componentes principais (PCA), quatro grupos foram identificados. O grupo composto apenas de solo + carvão vegetal e hidrogel enriquecido (2:2:1), foi considerado o melhor tratamento, pois favoreceu a maioria das características de crescimento vegetativo e vigor de emergência. O solo mais a areia com a adição de NPK não foi recomendado para a produção de mudas de maracujá azedo em nenhuma das proporções utilizadas, pois não houve emergência.(AU)

Kleiber ratios and growth curves of African Black and Red Neck ostrich breeds and their crossbreeds / Razão Kleiber e curva de crescimento para raças de avestruzes African Black e Red Neck e seus cruzamentos

The selection of animals with lower production costs can be achieved by using feed efficiency and growth curve information. Kleiber ratio (KR) is an alternative option for discriminating against the animals that have the greatest weight gain about their final weight. Alternative feed efficiency and growth curves for ostriches of the African Black (AB) and Red Neck (RN) breeds and their crossbreeds (CB) were investigated using KR and Gompertz equation. Univariate and multivariate analyses were used. The highest adult weight was identified in the RN and CB. AB was more precocious than the RN and CB individuals. Only AB animals reached 75% of their mature weight at one year of age. At 180 days, AB showed better KR. AB was different from the others, mainly for KR at 90 days and 180 days. Considering multivariate analysis, AB animals were different from the others, regardless of sex, mainly for KR at 90 days and KR at 180 days. Other subgroups separated the animals by sex. In a market preferring animals of minor structure (smaller cuts) and greater precocity, it would be suitable to opt for AB. When animals with greater body structure (larger cuts) are desired, males RN and CR is the best option, however, it will be slaughtered with greater age and lower value for KR (may generate a bigger production cost ). It is possible to obtain animals with precocity and high KR, being well represented by the AB breed.(AU)

A seleção de animais com custos de produção mais baixos pode ser alcançada usando a eficiência alimentar e informações da curva de crescimento. A razão de Kleiber (KR) é uma alternativa para discriminar os animais que apresentam maior ganho de peso em relação ao peso final. Eficiência alimentar alternativa e curvas de crescimento para avestruzes das raças African Black (AB) e Red Neck (RN) e seus cruzamentos (CB) foram investigadas usando a equação de KR e Gompertz. Análises univariadas e multivariadas foram utilizadas. O maior peso adulto foi observado no RN e no CB. AB foi mais precoce do que os indivíduos RN e CB. Apenas animais AB atingiram 75% de seu peso adulto até um ano de idade. Aos 180 dias, AB tem maior KR. AB foi diferente dos demais, principalmente para KR aos 90 dias e 180 dias. Considerando a análise multivariada, os animais AB diferiram dos demais, independente do sexo, principalmente pelos seguintes parâmetros: KR aos 90 dias, KR aos 180 dias. Outros subgrupos separaram os animais por sexo. Em um mercado que prefere animais de menor estrutura corporal (cortes menores) e maior precocidade, seria adequado optar pela AB. Para animais com maior estrutura corporal (cortes maiores), os machos RN e CR são a melhor opção, porém, serão abatidos com maior idade e menor valor para KR (pode gerar um maior custo de produção). É possível obter animais com precocidade e alto KR, sendo bem representados pelo AB.(AU)

Perception and risk management strategies for ranchers and their determinants: a case study from Turkey / Percepção e estratégias de gerenciamento de risco para fazendeiros e seus determinantes: um estudo de caso da Turquia

In this study, beef cattle farmers perceptions of risk and risk management strategies, and their determinants were analyzed using factor analysis and partial least squares regression analysis. The data set used in this study came from a survey conducted in Erzurum Province. The results demonstrated that variability in fodder price, insufficient farm income, uncertainty in government policies were perceived as the most important risks. Clean cattle shelter, off-farm income, monitoring and preventing livestock diseases were perceived as the most important risk management strategies. Results, also, demonstrated that some characteristics of farmers affected farmers perceptions. In this study, it was identified that the most important risk sources were economics-based. So, it was recommended that the government policy should be focused on preventing the fluctuations in input/output prices.(AU)

Neste estudo, as percepções dos pecuaristas de risco e estratégias de gestão de risco, e seus determinantes, foram analisados usando análise fatorial e análise de regressão de mínimos quadrados parciais. O conjunto de dados usado neste estudo veio de uma pesquisa realizada na província de Erzurum. Os resultados demonstraram que a variabilidade no preço da forragem, a renda agrícola insuficiente e a incerteza nas políticas governamentais foram percebidos como os riscos mais importantes. Abrigos para gado limpos, renda fora da fazenda, monitoramento e prevenção de doenças dos animais foram vistos como as estratégias de gestão de risco mais importantes. Os resultados, também, demonstraram que algumas características dos agricultores afetaram as percepções dos agricultores. Neste estudo, identificou-se que as fontes de risco mais importantes eram de base econômica. Assim, recomendou-se que a política do governo fosse voltada para a prevenção das oscilações nos preços de insumos / produtos.(AU)

Multiple comparisons of diversity indices invaded by Lantana camara / Análises múltiplas de índices de diversidade da invasiva Lantana camara

Current study assessed the impact of Lantana camara invasion on native plant diversity in Pothohar region of Pakistan. The approach used for study was random samplings and comparisons of diversity indices [number of species (S), abundance (N), species richness (R), evenness (J), Shannon diversity index (H) and Simpson index of dominance (lambda)] with two categorical factors i.e., invaded and non-invaded (control). Control plots harboured by an average of 1.74 more species/10m2. The control category was diverse (H=2.56) than invaded category (H=1.56). The higher value of species richness in control plots shows heterogeneous nature of communities and vice versa in invaded plots. At multivariate scale, ordination (nMDS) and ANOSIM showed significant magnitude of differences between invaded and control plots at all sites. The decrease in studied diversity indices in invaded over control sites indicated that plant communities become less productive due to Lantana invasion.(AU)

O presente estudo avaliou o impacto da invasão de Lantana camara na diversidade de plantas nativas na região de Pothohar, no Paquistão. A abordagem utilizada para o estudo foram a amostragem aleatória e a comparação de índices de diversidade, como número de espécies (S), abundância (N), riqueza de espécies (R), equitabilidade (J), índice de diversidade de Shannon (H) e índice de dominância de Simpson (lambda), com dois fatores categóricos, ou seja, invadidos e não invadidos (controle). As parcelas não invadidas tinham, em média, 1,74 espécie a mais / 10 m2 que parcelas invadidas. A categoria controle foi mais diversa (H = 2,56) do que a categoria invadida (H = 1,56). O maior valor da riqueza de espécies em parcelas de controle mostra a natureza heterogênea das comunidades, e vice-versa, em parcelas invadidas. Na escala multivariada, ordenação (nMDS) e ANOSIM mostraram magnitude significativa das diferenças entre as parcelas invadidas e controle em todos os locais. A diminuição nos índices de diversidade estudados em locais invadidos por controle indicou que as comunidades de plantas se tornam menos produtivas por causa da invasão de Lantana.(AU)

Exploratory data inference for detecting mastitis in dairy cattle

The aim of this study was to employ the principal component technique to physiological data and environmental thermohygrometric variables correlated with detection of clinical and subclinical mastitis in dairy cattle. A total of 24 lactating Girolando cows with different clinical conditions were selected (healthy, and with clinical or subclinical mastitis). The following physiological variables were recorded: udder surface temperature, ST (°C); eyeball temperature, ET (°C); rectum temperature, RT (°C); respiratory frequency, RF (mov. min-1). Thermohygrometric variables included air temperature, AirT (°C), and relative humidity, RU (%). ST was determined by means of thermal images, with four images per animal, on these quarters: front left side (FL), front right side (FR), rear right side (RR) and rear left side (RL), totaling 96 images. Exploratory data analysis was run through multivariate statistical technique with the employment of principal components, comprehending nine variables: ST on the FL, FR, RL and RR quarters; ET, RT; RF, AirT and RU. The representative quarters of the animals with clinical and subclinical mastitis showed udder temperatures 8.55 and 2.46° C higher than those of healthy animals, respectively. The ETs of the animals with subclinical and clinical mastitis were, respectively, 7.9 and 8.0% higher than those of healthy animals. Rectum temperatures were 2.9% (subclinical mastitis) and 5.5% (clinical mastitis) higher compared to those of healthy animals. Respiratory frequencies were 40.3% (subclinical mastitis) and 61.6% (clinical mastitis) higher compared to those of healthy animals. The first component explained 91% of the total variance for the variables analyzed. The principal component technique allowed verifying the variables correlated with the animals' clinical condition and the degree of dependence between the study variables.(AU)

Exploratory data inference for detecting mastitis in dairy cattle

The aim of this study was to employ the principal component technique to physiological data and environmental thermohygrometric variables correlated with detection of clinical and subclinical mastitis in dairy cattle. A total of 24 lactating Girolando cows with different clinical conditions were selected (healthy, and with clinical or subclinical mastitis). The following physiological variables were recorded: udder surface temperature, ST (°C); eyeball temperature, ET (°C); rectum temperature, RT (°C); respiratory frequency, RF (mov. min-1). Thermohygrometric variables included air temperature, AirT (°C), and relative humidity, RU (%). ST was determined by means of thermal images, with four images per animal, on these quarters: front left side (FL), front right side (FR), rear right side (RR) and rear left side (RL), totaling 96 images. Exploratory data analysis was run through multivariate statistical technique with the employment of principal components, comprehending nine variables: ST on the FL, FR, RL and RR quarters; ET, RT; RF, AirT and RU. The representative quarters of the animals with clinical and subclinical mastitis showed udder temperatures 8.55 and 2.46° C higher than those of healthy animals, respectively. The ETs of the animals with subclinical and clinical mastitis were, respectively, 7.9 and 8.0% higher than those of healthy animals. Rectum temperatures were 2.9% (subclinical mastitis) and 5.5% (clinical mastitis) higher compared to those of healthy animals. Respiratory frequencies were 40.3% (subclinical mastitis) and 61.6% (clinical mastitis) higher compared to those of healthy animals. The first component explained 91% of the total variance for the variables analyzed. The principal component technique allowed verifying the variables correlated with the animals' clinical condition and the degree of dependence between the study variables.

Maize hybrids contrasting for drought tolerance differ during the vegetative stage / Híbridos de milho contrastantes para tolerância à seca diferem durante o estágio vegetativo

Maize hybrids contrasting for drought tolerance differ during the vegetative stage. Drought is the main constraint on maize production in developing nations. Differences during development between genetic materials of maize grown under water restriction suggest that the plant can be improved with a view to its adaptation. In maize, sensitivity to water stress can occur at any stage of its phenological development. However, few studies report its effects on the vegetative phase of the cycle. On this basis, this study was conducted to examine how shoot and root-system indices are expressed in cultivation under water deficit as well as determine which indicators best explain the difference between hybrids in the evaluated water regimes. Commercial seeds of hybrids BR1055 and DKB-390 (drought-tolerant) and BRS1010 (drought-sensitive) were germinated in PVC tubes (1.0 m × 0.1 m) in a randomized complete block design, in a 3 × 2 factorial arrangement. The experiment was developed in a greenhouse where two water regimes were tested: no water stress and with water stress from the VE stage. The soil consisted of quartz sand mixed with a commercial fertilizer. Stem and root traits were evaluated up to the V5 growth stage. Relative chlorophyll content, leaf temperature, stem length, phenology, shoot dry biomass, root length, root dry biomass, root surface area, root volume and D95 were responsive to water deficit. The parameters that allowed the distinction between the hybrids in water the regimes were relative chlorophyll content, leaf temperature, phenology and average root diameter.(AU)

Híbridos de milho contrastantes para tolerância à seca diferem durante o estágio vegetativo. A seca é o principal fator de restrição para a produção de milho nas nações em desenvolvimento. Diferenças durante o desenvolvimento entre materiais genéticos de milho cultivados sob restrição de água sugerem que a planta pode ser melhorada visando a sua adaptação. No milho a sensibilidade ao estresse hídrico pode ocorrer em qualquer estágio do seu desenvolvimento fenológico. Contudo, poucos estudos relatam seus efeitos na fase vegetativa do ciclo. Desse modo, esse estudo teve como objetivos verificar como indicadores de parte aérea e sistema radicular se expressam mediante o cultivo sob déficit de água, bem como verificar quais indicadores melhor explicam a diferença entre híbridos nos regimes hídricos avaliados. Semente comerciais dos híbridos BR1055 e DKB-390 (tolerantes à seca) e BRS1010 (sensível à seca) foram germinadas em tubos de PVC (1,0 m x 0,1m) em delineamento em blocos completos em esquema fatorial 3 x 2. O ensaio foi realizado em casa de vegetação em dois regimes hídricos; sem estresse hídrico e com estresse hídrico a partir do estádio VE. O solo foi constituído de areia de quartzo misturada com um fertilizante comercial. As características do caule e da raiz foram avaliadas até o estádio de crescimento V5. O teor relativo de clorofila, a temperatura foliar, comprimento do caule, fenologia, biomassa seca da parte aérea, comprimento de raiz, biomassa seca de raiz, área de superfície radicular, volume de raiz e D95 foram responsivos ao déficit hídrico. Os parâmetros que permitiram a distinção entre os híbridos nos regimes hídricos foram o teor relativo de clorofila, temperatura foliar, fenologia e diâmetro médio da raiz.(AU)

Marcadores moleculares e descritores morfo-agronômicos na avaliação da diversidade genética de bucha (Luffa cylindrica) / Molecular markers and morpho-agronomic descriptors in the assessment genetic diversity of bucha (Luffa cylindrica)

O estudo da diversidade de Luffa cylindrica pode permitir triagens específicas para diferentes aplicações, visando uso e o melhoramento da espécie. Dados moleculares e de trinta descritores morfo-agronômicos foram utilizados em análises multivariadas na caracterização de 24 acessos de bucha provenientes de sete Estados brasileiros. Os resultados obtidos demonstraram que os acessos em estudo possuem ampla variabilidade potencial para todos os caracteres morfo-agronômicos analisados. Os caracteres que mais contribuíram para a divergência entre os acessos foram o comprimento dos frutos (62,32%) e a circunferência apical dos frutos (19,70%). Marcadores AFLP foram eficientes em agrupar os acessos de bucha provenientes de diferentes regiões brasileiras e apresentaram 66,8% de polimorfismo. O agrupamento obtido a partir da análise conjunta dos dados moleculares e morfo-agronômicos separou os acessos em quatro grupos e foi concordante com a análise bayesiana de agrupamento na separação dos acessos coletados no Norte com aqueles prospectados nas demais regiões brasileiras.

The study of the diversity of Luffa cylindrica may allow specific screening for different applications, aiming at the use and improvement of the species. Molecular data and thirty morpho-agronomic descriptors were used in multivariate analyzes to characterize 24 bushing accessions from seven Brazilian states. The results showed that the accessions under study have a wide potential variability for all the morpho-agronomic characters analyzed. The characters that most contributed to the divergence between the accessions were the fruit length (62.32%) and the apical circumference of the fruits (19.70%). AFLP markers were efficient in grouping the bushing access from different Brazilian regions and showed 66.8% of polymorphism. The clustering obtained from the joint analysis of molecular and morpho-agronomic data separated the accessions into four groups and was consistent with the Bayesian cluster analysis in the separation of accessions collected in the North with those prospected in the other Brazilian regions.

Marcadores moleculares e descritores morfo-agronômicos na avaliação da diversidade genética de bucha (Luffa cylindrica) / Molecular markers and morpho-agronomic descriptors in the assessment genetic diversity of bucha (Luffa cylindrica)

O estudo da diversidade de Luffa cylindrica pode permitir triagens específicas para diferentes aplicações, visando uso e o melhoramento da espécie. Dados moleculares e de trinta descritores morfo-agronômicos foram utilizados em análises multivariadas na caracterização de 24 acessos de bucha provenientes de sete Estados brasileiros. Os resultados obtidos demonstraram que os acessos em estudo possuem ampla variabilidade potencial para todos os caracteres morfo-agronômicos analisados. Os caracteres que mais contribuíram para a divergência entre os acessos foram o comprimento dos frutos (62,32%) e a circunferência apical dos frutos (19,70%). Marcadores AFLP foram eficientes em agrupar os acessos de bucha provenientes de diferentes regiões brasileiras e apresentaram 66,8% de polimorfismo. O agrupamento obtido a partir da análise conjunta dos dados moleculares e morfo-agronômicos separou os acessos em quatro grupos e foi concordante com a análise bayesiana de agrupamento na separação dos acessos coletados no Norte com aqueles prospectados nas demais regiões brasileiras.(AU)

The study of the diversity of Luffa cylindrica may allow specific screening for different applications, aiming at the use and improvement of the species. Molecular data and thirty morpho-agronomic descriptors were used in multivariate analyzes to characterize 24 bushing accessions from seven Brazilian states. The results showed that the accessions under study have a wide potential variability for all the morpho-agronomic characters analyzed. The characters that most contributed to the divergence between the accessions were the fruit length (62.32%) and the apical circumference of the fruits (19.70%). AFLP markers were efficient in grouping the bushing access from different Brazilian regions and showed 66.8% of polymorphism. The clustering obtained from the joint analysis of molecular and morpho-agronomic data separated the accessions into four groups and was consistent with the Bayesian cluster analysis in the separation of accessions collected in the North with those prospected in the other Brazilian regions.(AU)