Evaluation of the effect of phenolic pigments on rice germination under low temperature conditions / Avaliação do efeito de pigmentos fenólicos na germinação de arroz sob condições de baixa temperatura

In Rio Grande do Sul, the main rice producer State in Brazil, low temperatures can occur during germination and seedling establishment, and in some cases, during the reproductive stage. When low temperatures occur in the early developmental stages cause delay in germination, resulting in a non-homogeneous growing. In reproductive stage, low temperatures cause spikelet sterility, directly interfering with plant yield. Researchers have shown that some phenolic compounds such as proanthocyanidins and anthocyanin are associated with low temperature tolerance in plants due to their antioxidant capacity. The red and black color in the seeds of some rice genotypes is conferred by the phenolic compounds proanthocyanidins and anthocyanin, respectively. Therefore, tis study aimed to verify whether rice genotypes with red or black seeds are more tolerant to low temperatures during germination. In this study, five rice genotypes were tested, two present seeds without pigmentation and with contrasting response to low temperature tolerance (BRS Bojuru - tolerant and BRS Pampeira - sensitive), two genotypes with red seeds (BRS 902, SCS 119 Rubi) and one black seed genotype (SCS 120 Ônix). As expected, the genotypes with pigmented seeds had a greater total phenolic compounds content. However, under low temperature conditions, the genotypes with pigmented seed showed a similar response to the sensitive genotype. Therefore, the presence of proanthocyanidins and anthocyanin in the seed of the studied genotypes does not provide tolerance to low temperatures during germination.(AU)

No Rio Grande do Sul, principal estado produtor de arroz do Brasil, baixas temperaturas podem ocorrer durante a germinação e estabelecimento de plântulas, e em alguns casos, durante o estádio reprodutivo. Quando baixas temperaturas ocorrem no estádio inicial de desenvolvimento causam atraso da germinação, resultando em um crescimento não homogêneo. No estádio reprodutivo, baixas temperaturas podem ocasionar esterilidade das espiguetas, interferindo diretamente na produtividade da planta. Pesquisas têm mostrado que alguns compostos fenólicos como as proantocianidinas e antocianinas estão associadas com tolerância a baixa temperatura em plantas devido sua capacidade antioxidante. A coloração vermelha e preta nas sementes de alguns genótipos de arroz é conferida pelos compostos fenólicos proantocianidinas e antocianinas, respectivamente. Portanto, o objetivo desse estudo foi verificar se os genótipos de arroz com sementes vermelhas ou pretas são mais tolerantes a baixas temperaturas durante a germinação. Neste trabalho, cinco genótipos foram testados, dois com sementes sem pigmentação e com resposta contrastante para tolerância a baixa temperatura (BRS Bojuru - tolerante e BRS Pampeira - sensível), dois genótipos com sementes vermelhas (BRS 902, SCS 119 Rubi) e um genótipo com sementes pretas (SCS 120 Ônix). Como esperado, os genótipos com sementes pigmentadas têm maior conteúdo de compostos fenólicos totais. Entretanto, sob condições de baixa temperatura, os genótipos com semente pigmentada mostraram resposta similar ao genótipo sensível. Dessa forma, a presença de proantocianidinas e antocianinas nas sementes dos genótipos estudados não confere tolerância a baixas temperaturas durante a germinação.(AU)

Hypothermia in newly born piglets: Mechanisms of thermoregulation and pathophysiology of death

Mortality in piglets during the perinatal period, especially the first days after birth, is frequently caused by non infectious conditions, such as hypoglucemia or low birth weight, which can be associated with hypothermia experienced at birth. The thermal stability of newborn piglets is a fundamental aspect of neonatal care, so maintaining a constant, ideal temperature will substantially reduce newborn mortality. Species-specific characteristics, such as a limited capacity for thermoregulation, low energy reserves, a lack of brown adipose tissue (BAT) (-, and environmental conditions that are adverse for the piglet around the time of birth, including the absence of a microclimate, all of them contribute to difficulties in reaching thermal homeostasis in the first hours post-birth. Shivering thermogenesis and behavioral modifications to regulate body temperature through innate mechanisms allow animals to reduce their energy expenditures. Some body postures are effective in reducing contact with the floor and also nestling are useful to avoid heat loss, and also decreases heat dissipation. Achieving optimal development of thermoregulation is a challenge that newborns must confront to successfully adapt to extrauterine life. The objectives of this review, are to discuss the adverse factors that can lead to a death event due to hypothermia by analyzing the thermoregulation mechanisms at the central and cutaneous levels, also to analyze the harmful impacts that surviving neonate piglets confront in an unfavorable thermal environment, and to describe the pathophysiological mechanisms of death caused by hypothermia.(AU)

Hypothermia in newly born piglets: Mechanisms of thermoregulation and pathophysiology of death

Mortality in piglets during the perinatal period, especially the first days after birth, is frequently caused by non infectious conditions, such as hypoglucemia or low birth weight, which can be associated with hypothermia experienced at birth. The thermal stability of newborn piglets is a fundamental aspect of neonatal care, so maintaining a constant, ideal temperature will substantially reduce newborn mortality. Species-specific characteristics, such as a limited capacity for thermoregulation, low energy reserves, a lack of brown adipose tissue (BAT) (-, and environmental conditions that are adverse for the piglet around the time of birth, including the absence of a microclimate, all of them contribute to difficulties in reaching thermal homeostasis in the first hours post-birth. Shivering thermogenesis and behavioral modifications to regulate body temperature through innate mechanisms allow animals to reduce their energy expenditures. Some body postures are effective in reducing contact with the floor and also nestling are useful to avoid heat loss, and also decreases heat dissipation. Achieving optimal development of thermoregulation is a challenge that newborns must confront to successfully adapt to extrauterine life. The objectives of this review, are to discuss the adverse factors that can lead to a death event due to hypothermia by analyzing the thermoregulation mechanisms at the central and cutaneous levels, also to analyze the harmful impacts that surviving neonate piglets confront in an unfavorable thermal environment, and to describe the pathophysiological mechanisms of death caused by hypothermia.

Temperatura ambiente e idade do frango de corte sobre o valor energético do milho / Environmental temperature and broiler age on corn energy value

O objetivo deste trabalho foi determinar o efeito da temperatura ambiente e da idade da ave sobre o valor energético do milho. Foram utilizados 288 pintos de corte, da linhagem Cobb 500, distribuídos em delineamento experimental inteiramente casualizado em esquema de parcelas subdivididas no tempo, sendo as parcelas as três temperaturas de criação (fria: 18 ºC; termoneutra: 25 ºC e quente: 33 ºC) e as subparcelas as três idades de avaliação (inicial: 11 a 14; crescimento: 25 a 28 e final: 39 a 42 dias), com seis repetições de seis aves cada. A dieta basal foi composta por milho e farelo de soja. A dieta teste foi produzida substituindo a dieta basal pelo alimento teste: 40% de milho + 60% da dieta basal. Encontraram-se valores médios de energia metabolizável aparente, corrigida pelo balanço de nitrogênio (EMAn) do milho, para aves criadas em 18 ºC; 25 ºC e 33 ºC de 3322, 3279 e 3233 kcal/kg de matéria natural, respectivamente, e para as fases de 11 a 14; 25 a 28 e 39 a 42 dias de 3215, 3218 e 3400 kcal/kg de matéria natural, respectivamente. De um modo geral, os valores de energia metabolizável do milho, os balanços e os coeficientes de metabolizabilidade dos nutrientes da dieta teste aumentam com a idade do frango de corte, porém as energias metabolizáveis verdadeiras do milho não foram afetadas pela temperatura ambiente. Os balanços e os coeficientes de metabolizabilidade dos nutrientes da dieta teste foram reduzidos em estresse por calor para aves na fase de crescimento e final.

This study aimed to assess the effects of environmental temperature and age of broilers on the energy value of corn. A total of 288 Cobb 500 chicks were distributed in a complete randomized design with a split-plot arrangement and six replications of six chicks each. The main plot consisted of three temperatures (cold: 18 ºC; thermoneutral: 25 ºC; and hot: 33 ºC), while the secondary plot consisted of age (initial: 11 to 14 days; growing: 25 to 28 days; and final: 39 to 42 days). The basal diet was based on corn and soybean meal. The test diet was produced by replacing the basal diet for test food: 40% corn + 60% basal diet. The mean values of AMEn observed for broiler chicks under cold, thermoneutral, and hot temperatures were 3322, 3279, and 3233 kcal/kg of natural matter, respectively, and 3215, 3218, and 3400 kcal/ kg of natural matter for the initial, growing, and final phases, respectively. Overall, the metabolizable energy values of corn and the balance and coefficients of metabolizability of nutrients in the test diet increased with the broiler age, but the true metabolizable energies of corn were not affected by environmental temperature. The balance and coefficients of metabolizability of nutrients in the test diet decreased due to heat exposure during the growing and final phases.

Environmental temperature and broiler age on corn energy value / Temperatura ambiente e idade do frango de corte sobre o valor energético do milho

This study aimed to assess the effects of environmental temperature and age of broilers on the energy value of corn. A total of 288 Cobb 500 chicks were distributed in a complete randomized design with a split-plot arrangement and six replications of six chicks each. The main plot consisted of three temperatures (cold: 18 ºC; thermoneutral: 25 ºC; and hot: 33 ºC), while the secondary plot consisted of age (initial: 11 to 14 days; growing: 25 to 28 days; and final: 39 to 42 days). The basal diet was based on corn and soybean meal. The test diet was produced by replacing the basal diet for test food: 40% corn + 60% basal diet. The mean values of AMEn observed for broiler chicks under cold, thermoneutral, and hot temperatures were 3322, 3279, and 3233 kcal/kg of natural matter, respectively, and 3215, 3218, and 3400 kcal/ kg of natural matter for the initial, growing, and final phases, respectively. Overall, the metabolizable energy values of corn and the balance and coefficients of metabolizability of nutrients in the test diet increased with the broiler age, but the true metabolizable energies of corn were not affected by environmental temperature. The balance and coefficients of metabolizability of nutrients in the test diet decreased due to heat exposure during the growing and final phases.

O objetivo deste trabalho foi determinar o efeito da temperatura ambiente e da idade da ave sobre o valor energético do milho. Foram utilizados 288 pintos de corte, da linhagem Cobb 500, distribuídos em delineamento experimental inteiramente casualizado em esquema de parcelas subdivididas no tempo, sendo as parcelas as três temperaturas de criação (fria: 18 ºC; termoneutra: 25 ºC e quente: 33 ºC) e as subparcelas as três idades de avaliação (inicial: 11 a 14; crescimento: 25 a 28 e final: 39 a 42 dias), com seis repetições de seis aves cada. A dieta basal foi composta por milho e farelo de soja. A dieta teste foi produzida substituindo a dieta basal pelo alimento teste: 40% de milho + 60% da dieta basal. Encontraram-se valores médios de energia metabolizável aparente, corrigida pelo balanço de nitrogênio (EMAn) do milho, para aves criadas em 18 ºC; 25 ºC e 33 ºC de 3322, 3279 e 3233 kcal/kg de matéria natural, respectivamente, e para as fases de 11 a 14; 25 a 28 e 39 a 42 dias de 3215, 3218 e 3400 kcal/kg de matéria natural, respectivamente. De um modo geral, os valores de energia metabolizável do milho, os balanços e os coeficientes de metabolizabilidade dos nutrientes da dieta teste aumentam com a idade do frango de corte, porém as energias metabolizáveis verdadeiras do milho não foram afetadas pela temperatura ambiente. Os balanços e os coeficientes de metabolizabilidade dos nutrientes da dieta teste foram reduzidos em estresse por calor para aves na fase de crescimento e final.

Effect of Broiler Crating Density and Transportation Distance on Preslaughter Losses and Physiological Response During the Winter Season in Punjab, Pakistan

A study was conducted to determine the impact of crating density and transportation distance on losses and physiological response of broilers during the winter season. For this, ROSS-308 broilers were crated at three densities (i.e., 10, 12, and 15 birds/crate) in plastic crates and transported in three distances (i.e., 80, 160, and 240 km) during the winter season at 3.6 - 9.5ºC temperature and 63.3 - 78.8% relative humidity. Results showed that body weight loss increased significantly with the increase in transportation distance and decrease in crating density, whereas dead on arrival, physical injuries and bruises were not different among different transportation distance and crating density treatments. Significant reduction in carcass and breast yield was observed with the increase in transportation distance, whereas an increase in crating density above 12 birds per crate increased breast yield. Birds transported for 240 km had the highest serum catalase activity and the lowest rectal body temperature compared to other treatments. A gradual increase in crating density resulted in the increase in thyroxine concentration and reduction in rectal temperature. Serum glucose, albumin and uric acid concertation increased significantly after 160km of transportation, but serum triglyceride contents decreased. Moreover, an increase in crating density also increased serum glucose and triglyceride. Results suggested that longer transportation distance during the winter season increased body weight shrinkage with a reduction in carcass and breast yield, and the impact of losses and stress was greater in treatments having a lower number of birds in crates.(AU)

Effect of Broiler Crating Density and Transportation Distance on Preslaughter Losses and Physiological Response During the Winter Season in Punjab, Pakistan

A study was conducted to determine the impact of crating density and transportation distance on losses and physiological response of broilers during the winter season. For this, ROSS-308 broilers were crated at three densities (i.e., 10, 12, and 15 birds/crate) in plastic crates and transported in three distances (i.e., 80, 160, and 240 km) during the winter season at 3.6 - 9.5ºC temperature and 63.3 - 78.8% relative humidity. Results showed that body weight loss increased significantly with the increase in transportation distance and decrease in crating density, whereas dead on arrival, physical injuries and bruises were not different among different transportation distance and crating density treatments. Significant reduction in carcass and breast yield was observed with the increase in transportation distance, whereas an increase in crating density above 12 birds per crate increased breast yield. Birds transported for 240 km had the highest serum catalase activity and the lowest rectal body temperature compared to other treatments. A gradual increase in crating density resulted in the increase in thyroxine concentration and reduction in rectal temperature. Serum glucose, albumin and uric acid concertation increased significantly after 160km of transportation, but serum triglyceride contents decreased. Moreover, an increase in crating density also increased serum glucose and triglyceride. Results suggested that longer transportation distance during the winter season increased body weight shrinkage with a reduction in carcass and breast yield, and the impact of losses and stress was greater in treatments having a lower number of birds in crates.

Cold-Induced Ascites in Broilers: Effects of Vitamin C and Coenzyme Q10

ABSTRACT We hypothesized that the supplementation of vitamin C (Vit. C) and coenzyme Q10 (CoQ10) alone or in combination could reduce the negative effects of cold stress in broilers. Four hundred male chicks were exposed for 24 h to cold stress (15 ºC) starting from 15d of age, while a positive control group (PC, 100 birds) was kept under normal temperature condition. The experimental groups under cold stress (four treatments in 5 replicates of 20 birds) were: negative control (NC, basal diet), Vit. C (basal diet + 300 mg/kg Vit. C), CoQ10 (basal diet + 40 mg/kg CoQ10) and Vit. C plus CoQ10 (basal diet + Vit. C+ CoQ10at above mentioned doses). Vit. C or CoQ10 supplementation were restored (p 0.01) performance and lowered (p 0.01) ascites mortality. Blood hematocrit and hemoglobin concentration were decreased (p 0.01) to the level comparable to PC by Vit. C supplementation. Lower plasma concentrations of thyroxin (T4) and higher triiodothyronine (T3) were observed in NC birds (p 0.01) and were not affected by Vit. C or CoQ10. In conclusion, supplementation of Vit. C or CoQ10 in diet of broilers under cold stress conditions resulted improved performance parameters (body weight and feed conversion ratio) and ascites related traits (low red blood cell count, hematocrit, T3, and heart weights and high T4). No additional benefit was observed by combination of Vit. C and CoQ10.(AU)

Cold-Induced Ascites in Broilers: Effects of Vitamin C and Coenzyme Q10

ABSTRACT We hypothesized that the supplementation of vitamin C (Vit. C) and coenzyme Q10 (CoQ10) alone or in combination could reduce the negative effects of cold stress in broilers. Four hundred male chicks were exposed for 24 h to cold stress (15 ºC) starting from 15d of age, while a positive control group (PC, 100 birds) was kept under normal temperature condition. The experimental groups under cold stress (four treatments in 5 replicates of 20 birds) were: negative control (NC, basal diet), Vit. C (basal diet + 300 mg/kg Vit. C), CoQ10 (basal diet + 40 mg/kg CoQ10) and Vit. C plus CoQ10 (basal diet + Vit. C+ CoQ10at above mentioned doses). Vit. C or CoQ10 supplementation were restored (p 0.01) performance and lowered (p 0.01) ascites mortality. Blood hematocrit and hemoglobin concentration were decreased (p 0.01) to the level comparable to PC by Vit. C supplementation. Lower plasma concentrations of thyroxin (T4) and higher triiodothyronine (T3) were observed in NC birds (p 0.01) and were not affected by Vit. C or CoQ10. In conclusion, supplementation of Vit. C or CoQ10 in diet of broilers under cold stress conditions resulted improved performance parameters (body weight and feed conversion ratio) and ascites related traits (low red blood cell count, hematocrit, T3, and heart weights and high T4). No additional benefit was observed by combination of Vit. C and CoQ10.

PREBIÓTICOS NA ALIMENTAÇÃO DA TILÁPIA-DO-NILO SOB BAIXA TEMPERATURA: DESEMPENHO PRODUTIVO, RESPOSTAS FISIOLÓGICAS E MORFOLOGIA INTESTINAL

Sistemas intensivos são cada vez mais utilizados em espécies de crescente importância econômica, tal é o caso da tilápia do Nilo (Oreochromis niloticus), considerada uma espécie consolidada na aquicultura global e a mais importante na piscicultura brasileira. Na região Sul do país, principalmente, ocorrem alterações fisiológicas nos peixes quando há diminuição na temperatura da água nos meses de inverno, o que pode facilitar a ocorrência de doenças, e uma solução potencial para diminuir os distúrbios fisiológicos no animal é o uso de aditivos prebióticos como glucana e mananoligossacarídeos (MOS), que podem reforçar o sistema imune do peixe sob baixa temperatura da água. Em este estudo foram utilizados 180 juvenis de tilápia distribuídos aleatoriamente em 12 viveiros experimentais com temperatura média de 18,32 ± 1,83ºC, compondo um delineamento em inteiramente casualizado com três repetições, para avaliar as dietas: controle, sem suplementação de prebióticos (DC), 0,2% MOS de inclusão (DM), 0,2% -glucanas de inclusão (DG) e 0,1% MOS + 0,1% -glucanas de inclusão (DMG). Os peixes foram alimentados duas vezes ao dia (10h00m e 17h00m) por 90 dias. O desempenho produtivo, parâmetros hematológicos, imunológicos, e morfologia intestinal foram avaliados. O ganho de peso, índice de conversão alimentar, taxa de crescimento especifico e fator de condição não foram influenciados pelas dietas, o consumo da ração foi significativamente inferior com DG (P<0,05) quando comparado com DC. Não houve alterações na hematologia ou na bioquímica sanguínea (P>0,05) devido à inclusão de prebióticos na dieta. O nível de lisozima no soro foi aumentado por DM (P<0,05), no caso da lisozima no muco, foi aumentada pelos tratamentos DM e DG (P<0,05), quando comparados a DC. A maior resposta na atividade respiratória dos leucócitos foi observada em peixes alimentados com DMG (P<0,05). A função fagocitária dos leucócitos e o comprimento da altura das vilosidades intestinais foram maiores (P<0,05) nos peixes que receberam suplementos prebióticos quando comparados com os peixes que receberam DC. A suplementação dietética com 0,2% de MOS e 0,1% de MOS + 0,1% de -glucanas modulam positivamente a resposta imune não especifica e a morfologia intestinal, também, a inclusão de 0,2% de -glucanas na dieta melhoram a estrutura intestinal da tilápia do Nilo mantida a baixa temperatura da água por 90 dias.

Intensive systems are increasingly used in species of increasing economic importance, such as the Nile tilapia (Oreochromis niloticus), considered a consolidate species in global aquaculture and one of the most important in Brazilian fish farming. In the Southern region of the country, mainly, physiological changes occur in fish when there is a decrease in water temperature in the winter months, which can facilitate the occurrence of diseases, and a potential solution to reduce physiological disorders in the animal is the use of prebiotic additives such as -glucan and mannanoligosaccharides (MOS), which can boost the fish's immune system under low water temperature. In this study, 180 tilapia juveniles were randomly distributed in 12 experimental nurseries with an average temperature of 18,32 ± 1,83ºC, composing a completely randomized design with three replications, to evaluate the diets: control, without prebiotic supplementation (DC), 0.2% MOS inclusion (DM), 0.2% inclusion glucans (DG) and 0.1% MOS + 0.1% inclusion -glucans (DMG). The fish were fed twice a day (10h00m e 17h00m) for 90 days. Productive performance, hematological, immunological, and intestinal morphology parameters were evaluated. Weight gain, feed conversion index, specific growth rate and condition factor were not influenced by diets, feed intake was significantly lower with DG (P<0.05) when compared with DC. There were no changes in hematology or blood biochemistry (P>0.05) due to the inclusion of prebiotics in the diet. The level of lysozyme in serum was increased by DM (P<0.05), in the case of lysozyme in mucus, it was increased by treatments DM and DG (P<0.05), when compared to DC. The greatest response in the respiratory activity of leukocytes was observed in fish fed with DMG (P<0.05). The phagocytic function of the leukocytes and the length of the height of the intestinal villi were higher (P<0.05) in fish that received prebiotic supplements when compared to fish that received DC. Dietary supplementation with 0.2% MOS and 0.1% MOS + 0.1% -glucans positively modulates the non-specific immune response and intestinal morphology, as well as the inclusion of 0.2% - Dietary glucans improve the intestinal structure of Nile tilapia kept at low water temperature for 90 days.

MORFOLOGIA INTESTINAL DE CODORNAS EUROPEIAS (COTURNIX COTURNIX) SUPLEMENTADAS COM GLUTAMINA E ÁCIDO GLUTÂMICO E SUBMETIDAS A ESTRESSE TÉRMICO CRÔNICO

A avicultura desenvolveu-se muito nos últimos anos, sendo considerada um setor extremamente importante na produção de alimentos para a população mundial. A coturnicultura de corte é um dos setores da avicultura que, devido a vários fatores, tem se mostrado uma atividade muito atrativa, devido ao seu alto potencial produtivo, tanto para a produção industrial, como para pequenos produtores ou agricultores familiares. Objetivou-se avaliar como o estresse térmico afeta a morfologia intestinal de codornas europeias e se a suplementação dietética com glutamina associada ao ácido glutâmico pode minimizar os efeitos deletérios do estresse térmico sobre a morfologia intestinal das aves durante seu ciclo produtivo. No primeiro experimento, avaliou-se a morfologia intestinal de codornas europeias suplementadas com glutamina associada ao ácido glutâmico (Gln+Glu), submetidas ou não ao estresse térmico por frio, no período de 1 a 21 dias de idade. No segundo experimento, avaliouse a influência da suplementação dietética de glutamina associada ao ácido glutâmico (Gln+Glu) sobre a morfometria intestinal de codornas europeias submetidas ou não ao estresse térmico por calor, no período de 22 a 42 dias de idade. Em ambos os experimentos foram utilizadas 320 codornas europeias não sexadas, distribuídas em delineamento inteiramente casualizado (DIC), de acordo com esquema fatorial 2 x 2, sendo duas condições térmicas e duas dietas (dieta basal e dieta suplementada com 1% de Gln+Glu), com oito repetições e 10 aves por unidade experimental. As variáveis analisadas foram altura de vilosidade, largura de vilosidade, profundidade de cripta, relação vilosidade/cripta e área de absorção. Os dados foram submetidos à análise de variância, e as médias comparadas pelo teste de Tukey. No primeiro experimento, conclui-se que o estresse térmico por frio na fase inicial de vida das codornas europeias pode ser considerado um fator que afeta negativamente o desenvolvimento morfológico do intestino das aves. No segundo experimento, conclui-se que a suplementação influenciou positivamente a profundidade de cripta do duodeno, e a relação vilosidade/cripta do jejuno de codornas europeias sob estresse térmico por calor. Os efeitos deletérios do estresse térmico podem ser parcialmente revertidos com a suplementação por glutamina e ácido glutâmico quando a temperatura é elevada, porém, não quando a temperatura é baixa.

The poultry industry is considered an extremely important sector in the production of food for the world population. Quail production is one branch that has shown to be economically interesting due to its high productive potential, both for industrial production and for small producers or family farmers. This study evaluated how thermal stress affects the intestinal morphology of European quails and whether dietary supplementation with glutamine associated with glutamic acid can minimize the deleterious effects of thermal stress on the intestinal morphology of birds during their production cycle. In the first experiment, the intestinal morphology of European quails supplemented with glutamine associated with glutamic acid (Gln + Glu) was evaluated, submitted or not to cold thermal stress from 1 to 21 days of age. In the second experiment, the influence of dietary supplementation of glutamine associated with glutamic acid (Gln + Glu) on the intestinal morphometry of European quails subjected or not to heat stress from 22 to 42 days of age was evaluated. In both experiments, 320 non-sexed European quails were used, distributed in a completely randomized design (DIC), according to a 2 x 2 factorial scheme, with two thermal conditions and two diets (basal diet and diet supplemented with 1% Gln + Glu), with eight replicates and 10 birds per experimental unit. The variables analyzed were villus height, villus width, crypt depth, villus/crypt ratio and absorption area. The data were submitted to analysis of variance, and the means were compared using the Tukey test. In the first experiment, it was concluded that cold stress in the early life of European quails can be considered a factor that negatively affects the morphological development of the birds' intestines. In the second experiment, supplementation positively affected the crypt depth of the duodenum and the villus/crypt ratio of the jejunum of heat-stressed European quails. Negative effects cause by thermal stress may be partially minimized with glutamine and glutamic acid supplementation in high, but not in low, environmental temperature.

EFEITOS DO ESTRESSE POR FRIO EM PINTOS DE CORTE.

Essa pesquisa foi realizada com o objetivo de avaliar os efeitos do estresse causado pelo frio em pintos de corte, de um a 21 diasde idade, sobre o desempenho produtivo, o desenvolvimento dos órgãos, a atividade enzimática (lipase, amilase e proteínas totais), os parâmetros fisiológicos (frequência respiratória e temperatura retal), a relação heterófilo/linfócito e o coeficiente de metabolizabilidade da ração. Foi utilizado um total de 720 pintos de corte, distribuídos em quatro câmaras climáticas, contendo cada uma seis gaiolas, e essas, por sua vez, comportaram 30 aves cada. Os tratamentos foram definidos por quatro protocolos de temperatura ambiente na fase inicial de criação das aves. Cada câmara climática criou ambientes térmicos distintos em função da idade das aves (1, 2 e 3 semana), conforme demonstrado: conforto I 33, 30 e 27ºC; conforto II 30, 27 e 24ºC; estresse moderado - 24, 21 e 18ºC; estresse intenso - 22, 19 e 16ºC.O delineamento experimental foi inteiramente casualizado (DIC), com quatro tratamentos e seis repetições de 30 aves cada. Durante os primeiros 21 dias de idade, as aves submetidas às temperaturas de estresse moderado e estresse intenso apresentaram o menor ganho de peso e pior conversão alimentar. O peso relativo dos órgãos (coração, pulmão, pâncreas, proventrículo, moela e intestino delgado) também sofreu interferência dos dois tratamentos de estresseresultando em maior peso relativo do coração. O pulmão e o pâncreas apresentaram maior peso relativo sob os tratamentos de estresse moderado e intenso. O estresse por frio também provocou alterações na relação heterofilo/linfócito. Como indicativo disso, a relação foi maior para o frio moderado e intenso. Contudo, a despeito das alterações percebidas, as diferenças de temperatura não afetaram a atividade enzimática. Conclui-se que temperaturas abaixo da zona de conforto de pintos de corte nas três primeiras semanas de vida, causam estresse, afetando o seu desempenho, o desenvolvimento dos órgãos, padrões fisiológicos e hematológicos.

The study was conducted to evaluate the effects of cold stress in broiler chicks from one to 21 days of age, on performance, organs development, enzymatic activity (lipase, amylase and total protein), physiological parameters (respiratory rate and rectal temperature), heterophil/ lymphocyte ratio and feed metabolizability. A total of 720 birds were distributed randomly into four climatic chambers, each containing six cages, and the cage holds, initially, 30 chicks each. The treatments were defined by the temperature, in which each climatic chamber created distinct thermal environments according to the age of the birds, for the 1st, 2nd and 3rd weeks, respectively, as follows: Comfort I- 33, 30 and 27°C; Comfort II 30, 27 and 24°C; Moderate Cold Stress 24, 21 and 18°C; Intense Cold Stress 22, 19 and 16°C. During the first 21 days of age, the birds submitted to moderate and intense stress temperatures had the lowest weight gain and the worst feed conversion. The organs relative weights also were affected by the two stress treatments, resulting in a higher heart relative weight for the moderate and intense stress during the experiment period. The lungs and pancreas had the highest relative weight on the third week, with the stress treatments as well. The cold stress also affected the heretophile/lymphocyte ratio, on the first two weeks. The ratio was higher when the birds where submitted to moderate and intense cold stress. However, the temperature differences did not affect the enzyme activity. In conclusion, the temperatures below the comfort zone of broiler chicks on the first three weeks of age result in stress, affecting their performance, development, physiological and hematological standards.

Analysis of the stress-inducible transcription factor SsNAC23 in sugarcane plants

Stresses such as cold and drought can impair plant yield and induce a highly complex array of responses. Sugarcane (Saccharum spp.) is cultivated in tropical and subtropical areas and is considered a cold-sensitive plant. We previously showed that cold stress induces the expression of several genes in in vitro sugarcane plantlets. Here we characterize one of those genes, SsNAC23, a member of the NAC family of plant-specific transcription factors, which are induced by low temperature and other stresses in several plant species. The expression of SsNAC23 was induced in sugarcane plants exposed to low temperatures (4ºC). With the aim of further understanding the regulatory network in response to stress, we used the yeast two-hybrid system to identify sugarcane proteins that interact with SsNAC23. Using SsNAC23 as bait, we screened a cDNA expression library of sugarcane plants submitted to 4ºC for 48 h. Several interacting partners were identified, including stress-related proteins, increasing our knowledge on how sugarcane plants respond to cold stress. One of these interacting partners, a thioredoxin h1, offers insights into the regulation of SsNAC23 activity.

Analysis of the stress-inducible transcription factor SsNAC23 in sugarcane plants

Stresses such as cold and drought can impair plant yield and induce a highly complex array of responses. Sugarcane (Saccharum spp.) is cultivated in tropical and subtropical areas and is considered a cold-sensitive plant. We previously showed that cold stress induces the expression of several genes in in vitro sugarcane plantlets. Here we characterize one of those genes, SsNAC23, a member of the NAC family of plant-specific transcription factors, which are induced by low temperature and other stresses in several plant species. The expression of SsNAC23 was induced in sugarcane plants exposed to low temperatures (4ºC). With the aim of further understanding the regulatory network in response to stress, we used the yeast two-hybrid system to identify sugarcane proteins that interact with SsNAC23. Using SsNAC23 as bait, we screened a cDNA expression library of sugarcane plants submitted to 4ºC for 48 h. Several interacting partners were identified, including stress-related proteins, increasing our knowledge on how sugarcane plants respond to cold stress. One of these interacting partners, a thioredoxin h1, offers insights into the regulation of SsNAC23 activity.

COMPORTAMENTO DE FRANGOS DE CORTE EM DIFERENTES CONDIÇÕES TÉRMICAS

As mudanças e variações climáticas representam um desafio em manter a produção de frangos de corte, e encontrar um equilíbrio entre os custos de manter a temperatura ambiente adequada e otimizar a produção. O objetivo deste estudo foi avaliar o comportamento de frangos de corte em três condições térmicas distintas: frio, conforto e calor, analisando o comportamento, o desempenho produtivo e descrevendo padrões de comportamento. O experimento foi realizado em três câmaras climáticas monitoradas por câmeras de vídeo. Em cada semana foram utilizadas 27 aves, com identificação individual. O período experimental foi de quatro semanas, 3ª, 4ª, 5ª e 6ª semana de idade. As aves permaneciam alojadas nas câmaras durante cinco dias, 48 horas de adaptação e 72 horas de coleta de dados. Cada câmara proporcionava uma temperatura distinta: conforto (recomendação da linhagem), baixa (8°C abaixo do conforto) e alta (8°C acima do conforto) simulando condições convencionais em granjas. Para a avaliação do comportamento dos frangos de corte foram analisados 15 minutos de vídeos a cada 3 horas, e os dados de desempenho mensurados a cada 24 horas. O delineamento utilizado foi o inteiramente casualizado, com análise de variância e teste de médias de Tukey a 5%. Os comportamentos também foram avaliados por mineração de dados utilizando como classe as condições térmicas, aplicando o algoritmo J48. O comportamento de frangos de corte foi eficiente para manter a produtividade em condições de estresse em curto prazo. A mineração de dados possibilitou estabelecer padrões de comportamento aplicáveis como indicadores de condição térmica das aves. Estes são conhecimentos importantes para a sustentabilidade da produção de frangos de corte, pois auxiliam na tomada de decisão em medidas de mitigação.

The climate changes are a challenge to maintain the production of broiler, and find a balance between the costs of maintaining the proper temperature and optimize production. The aim of this study was to evaluate broiler behavior in three different thermal conditions: comfort, cold and heat, analyzing the behavior and production performance. The experiment was conducted in three climatic chambers, and monitored by video cameras. Each week were used 27 birds, divided between the chambers and individually identified. The experiment period was: 3rd, 4th, 5th and 6th week of age from broilers. The birds remained housed in the chamber for five days, 48 hours of adaptation and 72 hours to collect data. Each compartment of the chamber provides a different temperature: comfort (recommendation strain), low (8 °C below the comfort) and high (8 °C above the comfort) simulating conventional housing conditions. To evaluate the broiler behavior were analyzed 15 minutes of video every 3 hours, and the performance data. The experimental design was completely randomized with variance analysis and Tukey test at 5%. The behaviors were evaluated too with data mining, using thermal conditions class, applying J48 algorithm. The broiler behaviors were efficient to maintain productivity in short-term stress conditions. With data mining was possible to establish behavior standards applicable to thermal condition indicators of broilers. These are important knowledge for the sustainability of broilers production, helping in decision making for mitigation measures.

Cold induced changes on sugar contents and respiratory enzyme activities in coffee genotypes

The present research aimed to characterize some biochemical responses of Coffea canephora (clones 02 and 153) and C. arabica (Catucaí IPR 102) genotypes subjected to low positive temperatures, helping to elucidate the mechanisms involved in cold tolerance. For that, one year old plants were subjected successively to 1) a temperature decrease (0.5°C a day) from 25/20°C to 13/8°C (acclimation period), 2) a three day chilling cycle (3x13/4°C) and to 3) a recovery period of 14 days (25/20°C). In Catucaí (less cold sensitive when compared to clone 02) there was an increased activity in the respiratory enzymes malate dehydrogenase and pyruvate kinase. Furthermore, Catucaí showed significant increases along the cold imposition and the higher absolute values after chilling exposure of the soluble sugars (sucrose, glucose, fructose, raffinose, arabinose and mannitol) that are frequently involved in osmoregulation and membrane stabilization/protection. The analysis of respiratory enzymes and of soluble sugar balance may give valuable information about the cold acclimation/tolerance mechanisms, contributing to a correct selection and breeding of Coffea sp. genotypes.

A pesquisa teve por objetivo caracterizar respostas bioquímicas de genótipos de Coffea canephora (clones 02 and 153) e C. arabica (Catucaí IPR 102) submetidos a baixas temperaturas positivas, ajudando a elucidar os mecanismos envolvidos na tolerância ao frio. Plantas com um ano de idade foram submetidas sucessivamente a 1) decréscimo da temperatura (0,5°C por dia) desde 25/20°C até 13/8°C (período de aclimatização), 2) um ciclo de três dias a 13/4°C e 3) 14 dias de recuperação (25/20°C). Em Catucaí, genótipo menos sensível ao frio quando comparado com o clone 02, observou-se um aumento das atividades das enzimas malato desidrogenase e piruvate cinase, relacionadas com a respiração. Nesse genótipo, os níveis de açúcares solúveis sacarose, glucose, frutose, rafinose, arabinose e manitol (frequentemente envolvidos em processos de regulação osmótica e estabilização/proteção de membranas) aumentam significativamente durante a imposição de baixas temperaturas, mostrando ainda os valores absolutos mais elevados depois de exposição a 4°C. Portanto, a análise de enzimas respiratórias e do balanço de açúcares solúveis pode fornecer informação importante sobre mecanismos de aclimatização/tolerância ao frio, contribuindo para seleção e melhoramento de genótipos de Coffea sp.

Cold induced changes on sugar contents and respiratory enzyme activities in coffee genotypes

The present research aimed to characterize some biochemical responses of Coffea canephora (clones 02 and 153) and C. arabica (Catucaí IPR 102) genotypes subjected to low positive temperatures, helping to elucidate the mechanisms involved in cold tolerance. For that, one year old plants were subjected successively to 1) a temperature decrease (0.5°C a day) from 25/20°C to 13/8°C (acclimation period), 2) a three day chilling cycle (3x13/4°C) and to 3) a recovery period of 14 days (25/20°C). In Catucaí (less cold sensitive when compared to clone 02) there was an increased activity in the respiratory enzymes malate dehydrogenase and pyruvate kinase. Furthermore, Catucaí showed significant increases along the cold imposition and the higher absolute values after chilling exposure of the soluble sugars (sucrose, glucose, fructose, raffinose, arabinose and mannitol) that are frequently involved in osmoregulation and membrane stabilization/protection. The analysis of respiratory enzymes and of soluble sugar balance may give valuable information about the cold acclimation/tolerance mechanisms, contributing to a correct selection and breeding of Coffea sp. genotypes.

A pesquisa teve por objetivo caracterizar respostas bioquímicas de genótipos de Coffea canephora (clones 02 and 153) e C. arabica (Catucaí IPR 102) submetidos a baixas temperaturas positivas, ajudando a elucidar os mecanismos envolvidos na tolerância ao frio. Plantas com um ano de idade foram submetidas sucessivamente a 1) decréscimo da temperatura (0,5°C por dia) desde 25/20°C até 13/8°C (período de aclimatização), 2) um ciclo de três dias a 13/4°C e 3) 14 dias de recuperação (25/20°C). Em Catucaí, genótipo menos sensível ao frio quando comparado com o clone 02, observou-se um aumento das atividades das enzimas malato desidrogenase e piruvate cinase, relacionadas com a respiração. Nesse genótipo, os níveis de açúcares solúveis sacarose, glucose, frutose, rafinose, arabinose e manitol (frequentemente envolvidos em processos de regulação osmótica e estabilização/proteção de membranas) aumentam significativamente durante a imposição de baixas temperaturas, mostrando ainda os valores absolutos mais elevados depois de exposição a 4°C. Portanto, a análise de enzimas respiratórias e do balanço de açúcares solúveis pode fornecer informação importante sobre mecanismos de aclimatização/tolerância ao frio, contribuindo para seleção e melhoramento de genótipos de Coffea sp.

Cold induced changes on sugar contents and respiratory enzyme activities in coffee genotypes

The present research aimed to characterize some biochemical responses of Coffea canephora (clones 02 and 153) and C. arabica (Catucaí IPR 102) genotypes subjected to low positive temperatures, helping to elucidate the mechanisms involved in cold tolerance. For that, one year old plants were subjected successively to 1) a temperature decrease (0.5°C a day) from 25/20°C to 13/8°C (acclimation period), 2) a three day chilling cycle (3x13/4°C) and to 3) a recovery period of 14 days (25/20°C). In Catucaí (less cold sensitive when compared to clone 02) there was an increased activity in the respiratory enzymes malate dehydrogenase and pyruvate kinase. Furthermore, Catucaí showed significant increases along the cold imposition and the higher absolute values after chilling exposure of the soluble sugars (sucrose, glucose, fructose, raffinose, arabinose and mannitol) that are frequently involved in osmoregulation and membrane stabilization/protection. The analysis of respiratory enzymes and of soluble sugar balance may give valuable information about the cold acclimation/tolerance mechanisms, contributing to a correct selection and breeding of Coffea sp. genotypes.

A pesquisa teve por objetivo caracterizar respostas bioquímicas de genótipos de Coffea canephora (clones 02 and 153) e C. arabica (Catucaí IPR 102) submetidos a baixas temperaturas positivas, ajudando a elucidar os mecanismos envolvidos na tolerância ao frio. Plantas com um ano de idade foram submetidas sucessivamente a 1) decréscimo da temperatura (0,5°C por dia) desde 25/20°C até 13/8°C (período de aclimatização), 2) um ciclo de três dias a 13/4°C e 3) 14 dias de recuperação (25/20°C). Em Catucaí, genótipo menos sensível ao frio quando comparado com o clone 02, observou-se um aumento das atividades das enzimas malato desidrogenase e piruvate cinase, relacionadas com a respiração. Nesse genótipo, os níveis de açúcares solúveis sacarose, glucose, frutose, rafinose, arabinose e manitol (frequentemente envolvidos em processos de regulação osmótica e estabilização/proteção de membranas) aumentam significativamente durante a imposição de baixas temperaturas, mostrando ainda os valores absolutos mais elevados depois de exposição a 4°C. Portanto, a análise de enzimas respiratórias e do balanço de açúcares solúveis pode fornecer informação importante sobre mecanismos de aclimatização/tolerância ao frio, contribuindo para seleção e melhoramento de genótipos de Coffea sp.

COMPORTAMENTO TERMORREGULATÓRIO E DESEMPENHO DE LEITÕES DESMAMADOS SUBMETIDOS A DOIS AMBIENTES TÉRMICOS

Objetivou-se verificar a influência do ambiente térmico e das fases de desenvolvimento sobre o comportamento termorregulatório e desempenho de leitões desmamados. Para tanto, foram utilizados 64 leitões de linhagem comercial (32 machos castrados e 32 fêmeas) desmamados aos 25 dias de idade. Os leitões foram submetidos a dois ambientes térmicos (Estresse por frio e Conforto térmico), dos 28 aos 49 dias (Fase 1) e dos 50 aos 65 dias (Fase 2). Foram registrados os padrões de comportamento ingestivo, relações sociais, comportamento de espaçamento e localização, comportamento de termorregulação e atividades excretórias. Ademais, ganho de peso, consumo de ração e conversão alimentar foram avaliados. Os animais foram distribuídos em um delineamento inteiramente ao acaso. Observou-se maior interação entre os animais durante a primeira fase, para ambos os ambientes. Durante a segunda fase os animais permaneceram mais tempo no comedouro, nos dois ambientes testados. Em ambas as fases, no ambiente de estresse por frio houve preferência dos animais em permanecer em grupo. A posição de decúbito lateral foi a preferida pelos leitões no ambiente de conforto térmico, para as duas fases de desenvolvimento. No ambiente de estresse por frio a posição de decúbito esternal foi a mais utilizada pelos leitões em ambas as fases e o consumo de ração e o ganho de peso foram maiores na Fase 2. A conversão alimentar foi melhor no ambiente de conforto térmico. Em situação de estresse por frio, leitões dos 28 aos 65 dias de vida aumentam a frequência ao comedouro e o tempo de alimentação, no entanto, o ambiente térmico não influencia na quantidade do alimento ingerido. Leitões desmamados interagem mais com companheiros durante a primeira metade da fase de creche e, o ambiente de estresse por frio não influencia nesse comportamento. Em ambiente térmico abaixo da zona de conforto, leitões utilizam por mais tempo o agrupamento com companheiros de ninhada e a posição de decúbito esternal como importantes ajustes comportamentais. No entanto, em ambiente de termoneutralidade, os animais permanecem mais tempo afastados uns dos outros. A conversão alimentar de leitões na fase de creche piora com a redução da temperatura abaixo da zona de termoneutralidade.

This study aimed to verify the influence of the thermal environment and development phases of the thermoregulatory behavior and performance of weaned piglets. To this end, commercial line of 64 piglets were used (32 barrows and 32 females) weaned at 25 days of age. The piglets were subjected to two thermal environments (stress for cold and thermal comfort), from 28 to 49 days (Phase 1) and from 50 to 65 days (Phase 2). The feeding behavior patterns were recorded, social relationships, spacing behavior and location, behavioral thermoregulation and excretory activities. In addition, weight gain, feed intake and feed conversion were evaluated. The animals were distributed in a completely randomized design. There was more interaction between the animals during the first phase, for both environments. During the second phase, the animals spent more time at the feeder in both environments tested. In both phases, in a cold stress environment was preferred animals to remain in the group. Pigs in the thermal comfort preferred the lateral decubitus position for the two stages of development. In a cold stress environment to sternal decubitus position was the most used by piglets in both stages and the feed intake and weight gain were greater in Phase 2. The feed conversion was better in thermal comfort. In a situation of stress by cold, piglets of 28 to 65 days of life to increase the frequency and the power feeder of time, however, the thermal environment does not influence the quantity of ingested food. Weaners interact more with teammates during the first half of the nursery phase, and by cold stress environment does not influence this behavior. In thermal environment below the comfort zone, piglets use for longer muster with littermates and sternal decubitus position as major behavioral adjustments. However, in a thermoneutral environment, the animals remain more time away from each other. The feed conversion of piglets in nursery phase worsening by reducing the temperature below the thermal neutral zone.

PLASMA SANGUÍNEO DESIDRATADO NA ALIMENTAÇÃO DA TILÁPIA-DO-NILO

Este estudo avaliou a inclusão de plasma sanguíneo desidratado (PD) na dieta da tilápia-do-Nilo por meio de uma pesquisa dividida em duas fases: na Fase I, com duração de 60 dias, avaliou-se o desempenho produtivo e parâmetros histológicos dos peixes alimentados com cinco dietas: PD0 (controle); PD 1,66; PD 3,32; PD 4,97; PD 6,63% de inclusão de PD. Para isto distribuiu-se 440 peixes em 40 aquários de 250 L dotados de filtro físico e biológico com controle de temperatura (26 ±1°C). Na Fase II avaliou-se os parâmetros hematológicos de juvenis de tilápia-do- Nilo, antes e após o estresse por baixa temperatura (16°C) durante sete dias, utilizandose de 60 peixes distribuídos aleatoriamente em 30 aquários de 40 L, dotados de biofiltros e aeração individuais. A inclusão de PD determinou maior ganho de peso e peso final e melhora da integridade intestinal. Manutenção e/ou estímulo à eritropoiese foi observado com a inclusão de PD inferindo melhor higidez e resistência orgânica aos peixes expostos ao estresse por baixa temperatura. Aumento na produção de neutrófilos e manutenção de monócitos demonstrou o efeito estimulatório do PD sobre o sistema imune inato. Os dados foram submetidos à análise de variância (P<0,05), complementado pelo teste de comparações múltiplas de Tukey. Foram realizadas análises de regressão nos casos em que o modelo foi significativo (R2 >0,70). Para dados fora da curva de normalidade, aplicou-se o teste não paramétrico de Kruskal- Wallis (P<0,05), complementados com o teste de comparações de Mann-Whitney. A inclusão de PD à dieta de Oreochromis niloticus melhora o desempenho produtivo, a saúde intestinal, perfil hematológico e resistência orgânica ao estresse por baixa temperatura. Com base nos resultados de desempenho e histologia, recomenda-se o nível de inclusão de 4,97% à dieta, pois traz mais benefícios quando comparado ao tratamento sem inclusão.

DEHYDRATED BLOOD PLASMA IN THE FEEDING NILE TILAPIA This study evaluated the inclusion of dehydrated blood plasma (PD) on Nile tilapia diet by a research divided in two stages: 1° Stage, after 60 days, was measured the productive performance and histological parameters of fish, whose received five diets: PD0 (control); PD 1,66; PD 3,32; PD 4,97; PD 6,63% of dehydrated blood plasma inclusion. 440 fish was randomized into 40 aquariums (250 L) with physic-biological filter and automatic system water control (26 ±1°C) on the 1°st. On the second stage, was evaluated hematological parameters of Nile tilapia juveniles, before and after the cold stress (16°C). During seven days, 60 fish were allocated in 30 aquariums (40 L), with individual aeration and filters, provided by a division in each, that assure individuals spaces. PD inclusion results presented greater weight gain, final weight and improves the intestinal integrity. Maintenance and/or stimulation of erythropoiesis was observed with the addition of PD, inferring better health and fish organic resistance exposed to stress by low temperature. Increased production of neutrophils and monocytes maintenance, demonstrated the stimulatory effect of PD on the innate immune system . The data was submitted to the analysis technique variance (P<0.05), complemented by the multiple comparison Tukey test. Regression analyzes were performed when the model was significant (R2>0.70). For outresults of the normal curve, was applied the nonparametric Kruskal-Wallis analysis (P<0,05), complemented by Mann-Whitney test comparisons. The inclusion of PD for Oreochromis niloticus on diet, improves growth performance, gut health, blood profile and organic resistance to stress by low temperature. Based on the results of growth performance and histology, is recommended the PD inclusion of 4.97 % on the diet, because it brings more benefits when compared to PD treatment without inclusion. Key words: blood plasma, cold-stress, hematology, histology, productive performance.