Delinted cottonseed in diets for finishing sheep.

The use of agricultural by-products might provide an important alternative to improve animal agriculture and to reduce feeding costs. The effects of inclusion in the diet of four levels of delinted cottonseed (0, 80, 160, and 240 g/kg) on intake, digestibility, nitrogen balance, blood parameters, and the ingestive behaviour of confined sheep were studied. Twenty-four mixed-breed rams with an average body weight of 27.6 ± 2.9 kg were used in a completely randomised design with four treatments. The addition of delinted cottonseed (DCS) did not alter (P > 0.05) the intake of dry matter, crude protein, organic matter, neutral detergent fibre, or ether extract in the two forms calculated (g/day and % body weight). The use of different levels of DCS in sheep feed did not influence (P > 0.05) the voluntary water intake. The dietary DCS levels linearly affected (P < 0.05) the digestibility coefficients of the dry matter (DM), organic matter, neutral detergent fibre, ether extract, and non-fibrous carbohydrates. The DCS inclusion levels did not affect the nitrogen balance (P = 0.22), plasma concentrations of urea (P = 0.51), and glucose (P = 0.17).The feeding efficiency and rumination in g DM/h reduced linearly (P < 0.05) with the addition of DCS in the diet. Therefore, the addition of delinted cottonseed affects the intake, digestibility, and ingestive behaviour of confined sheep, and the addition of up to 80 g/kg delinted cottonseed in the diet of confined sheep is recommended.

Mitochondrial dysfunction: maternal protein restriction as a trigger of reactive species overproduction and brainstem energy failure in male offspring brainstem.

Mitochondria are important organelles in eukaryotic organisms, wherein their capacity to produce energy vary among the tissues depending upon the amounts of oxygen consumed. Part of the oxygen consumed during ATP generation produces reactive oxygen species, which if not efficiently removed can trigger a systemic damage to molecular compounds characterized as oxidative stress. Several studies have demonstrated that mitochondrial dysfunction and oxidative stress in the central nervous system (CNS) are related to a plethora of neural disorders. Herein, we hypothesize that a late autonomic imbalance-induced hypertension might be related to long-lasting effects of protein restriction during the critical period of the CNS development on the mitochondrial function and oxidative stress in the brainstem of adult (i.e. 150 days of age) male Wistar rats. Maternal protein restriction was induced by offering a diet based on 8% of casein from first day of pregnancy until weaning, when the male pups started to receive laboratory chow up to 150 days of life. The protein restriction induced an extended detrimental modulation in mitochondria function, decreasing the phosphorylation capacity with concomitant decrease in the mitochondrial membrane potential, wherein the reactive species overproduction triggered a disruption in proton conductance, which may gradually compromise mitochondria energy conservation. Interestingly, the elevated activity of glutathione-S-transferase and the augmented expression of uncoupling protein 2 are likely protective mechanisms induced by lipid peroxidation products, being feasible molecular changes attempting to deal with oxidative stress-induced ageing.

Thermal and photo-stability of the antioxidant potential of Spirulina platensis powder / Estabilidade térmica e fotoestabilidade do potencial antioxidante de Spirulina platensis em pó

Abstract This work aimed to evaluate the thermal and photo stability of the antioxidant potential (AP) of the Spirulina platensis biomass. Thermal stability was established at 25ºC, 40ºC and 50ºC for 60 days, in the dark, protected from light. Photo stability was evaluated using UV (15 W, λ = 265 nm) and fluorescent (20 W, 0.16 A, power factor FP > 0.5, 50/60 Hz, 60 lm/w, 1200 lm) light for 90 days in capsules, glass and Petri dishes, at room temperature. The AP of the biomass in these conditions was determined at intervals (every 7 and 30 days in the studies of thermal and photo stability, respectively) using the induction of the oxidation of a lipid system by heat and aeration. In this lipid system, the biomass submitted to degradation was used as an antioxidant. The kinetics of the reaction was determined by the Arrhenius method. Thermal degradation was found to follow zero order kinetics, whereas photo degradation followed first order kinetics. The AP decreased 50% after 50 days at 25°C. At 40°C and 50°C, the AP decreased more than 50% after 35 and 21 days of exposition, respectively. The decrease of the AP of Spirulina was more sensible to UV and fluorescence light. After 30 days of exposition, the AP decreased more than 50% in all storage conditions tested. The antioxidant potential of Spirulina platensis is easily degraded when the biomass is exposed to heat and light, indicating the need for care to be taken in its storage.

Resumo Este trabalho objetivou avaliar a estabilidade térmica e a foto-estabilidade do potencial antioxidante (PA) da biomassa da Spirulina platensis. A estabilidade térmica foi avaliada a 25ºC, 40ºC e 50ºC por 60 dias. A foto-estabilidade foi avaliada usando luz UV (15 W, λ = 265 nm) e fluorescente (20 W, 0.16 A, fator de potência FP > 0.5, 50/60 Hz, 60 lm/w, 1200 lm) por 90 dias em cápsulas, vidro e placas de Petri. O PA da biomassa nessas condições foi determinado em intervalos de tempo (a cada 7 e 30 dias nos estudos de estabilidade térmica e foto-estabilidade, respectivamente), usando a indução da oxidação de um sistema lipídico por calor e aeração. Neste sistema lipídico, a biomassa submetida à degradação foi usada como antioxidante. A cinética da reação foi determinada pelo método de Arrhenius. A degradação térmica seguiu uma cinética de zero ordem, enquanto que a fotodegradação seguiu uma cinética de primeira ordem. O PA diminuiu 50% depois de 50 dias a 25°C. A 40°C e 50°C, o PA diminuiu mais de 50% depois de 35 e 21 dias de exposição, respectivamente. A diminuição do PA da Spirulina foi mais sensível à luz UV e fluorescente. Depois de 30 dias de exposição, o PA diminuiu mais de 50% em todas as condições de armazenamento testadas. O potencial antioxidante da Spirulina platensis é facilmente diminuído quando a biomassa é exposta ao calor e a luz, indicando a necessidade de cuidados durante seu armazenamento.

Thermal and photo-stability of the antioxidant potential of Spirulina platensis powder.

This work aimed to evaluate the thermal and photo stability of the antioxidant potential (AP) of the Spirulina platensis biomass. Thermal stability was established at 25ºC, 40ºC and 50ºC for 60 days, in the dark, protected from light. Photo stability was evaluated using UV (15 W, λ = 265 nm) and fluorescent (20 W, 0.16 A, power factor FP > 0.5, 50/60 Hz, 60 lm/w, 1200 lm) light for 90 days in capsules, glass and Petri dishes, at room temperature. The AP of the biomass in these conditions was determined at intervals (every 7 and 30 days in the studies of thermal and photo stability, respectively) using the induction of the oxidation of a lipid system by heat and aeration. In this lipid system, the biomass submitted to degradation was used as an antioxidant. The kinetics of the reaction was determined by the Arrhenius method. Thermal degradation was found to follow zero order kinetics, whereas photo degradation followed first order kinetics. The AP decreased 50% after 50 days at 25°C. At 40°C and 50°C, the AP decreased more than 50% after 35 and 21 days of exposition, respectively. The decrease of the AP of Spirulina was more sensible to UV and fluorescence light. After 30 days of exposition, the AP decreased more than 50% in all storage conditions tested. The antioxidant potential of Spirulina platensis is easily degraded when the biomass is exposed to heat and light, indicating the need for care to be taken in its storage.

Protein undernutrition during development and oxidative impairment in the central nervous system (CNS): potential factors in the occurrence of metabolic syndrome and CNS disease.

Mitochondria play a regulatory role in several essential cell processes including cell metabolism, calcium balance and cell viability. In recent years, it has been postulated that mitochondria participate in the pathogenesis of a number of chronic diseases, including central nervous system disorders. Thus, the concept of mitochondrial function now extends far beyond the common view of this organelle as the 'powerhouse' of the cell to a new appreciation of the mitochondrion as a transducer of early metabolic insult into chronic disease in later life. In this review, we have attempted to describe some of the associations between nutritional status and mitochondrial function (and dysfunction) during embryonic development with the occurrence of neural oxidative imbalance and neurogenic disease in adulthood.

Fluoxetine induces lean phenotype in rat by increasing the brown/white adipose tissue ratio and UCP1 expression.

The serotonergic system plays a crucial role in the energy balance regulation. Energy balance is mediated by food intake and caloric expenditure. Thus, the present study investigated the mechanisms that might be associated with fluoxetine treatment-induced weight reduction. Wistar male rat pups received daily injections with subcutaneous fluoxetine (Fx-group) or vehicle solution (Ct-group) from day 1 until 21 days of age. Several analyses were conducted to verify the involvement of mitochondria in weight reduction. We found that body weight in the Fx-group was lower compared to control. In association to lower fat mass in the Fx-group (25%). Neither neonatal caloric intake nor food intake reveals significant differences. Evaluating caloric expenditure (locomotor activity and temperature after stimulus), we did not observe differences in locomotor activity. However, we observed that the Fx group had a higher capacity to maintain body temperature in a cold environment compared with the Ct-group. Since brown adipose tissue-(BAT) is specialized for heat production and the rate of heat production is related to mitochondrial function, we found that Fx-treatment increases respiration by 36%, although after addition of GDP respiration returned to Ct-levels. Examining ROS production we observe that Fx-group produced less ROS than control group. Evaluating uncoupling protein (UCP) expression we found that Fx-treatment increases the expression by 23%. Taken together, our results suggest that modulation of serotonin system results in positive modulation of UCP and mitochondrial bioenergetics in brown fat tissue.

Zeólita na dieta de bovinos de corte / Zeolite in the diet of beef cattle

Avaliou-se o efeito da inclusão de zeólita na dieta de bovinos de corte sobre os parâmetros ruminais, as digestibilidades total e parcial, a produção de nitrogênio, a eficiência microbiana e as características do sangue. Os tratamentos, com base na matéria seca (MS) da dieta, foram: 0; 0,75; 1,5; 2,25 e 3,0% de zeólita. Utilizaram-se cinco bovinos machos mestiços, fistulados no rúmen e abomaso, alimentados com silagem de milho e concentrado, representando 65% de volumoso e 35% de concentrado. O delineamento utilizado foi em quadrado latino 5×5, com cinco períodos de 15 dias. Os animais receberam 15g de dióxido de titânio (TiO2) do terceiro ao 12º dia de cada período. Houve efeito (P<0,05) sobre o consumo diário (kg/dia) de proteína bruta (PB) e efeito (P<0,05) sobre o consumo de MS e de fibra em detergente neutro corrigida para cinza e proteína, expresso em g/kg de peso. A digestibilidade total dos nutrientes digestíveis totais (NDT) foi influenciada pelos tratamentos (P<0,05). A digestibilidade ruminal dos carboidratos não fibrosos (CNF) foi afetada quadraticamente (P<0,05), assim como a intestinal da PB e dos CNF. A ingestão e a excreção fecal de nitrogênio (g/dia) foram influenciadas linearmente (P<0,05) pela inclusão de zeólita. Concluiu-se que a adição de zeólita na dieta, embora tenha aumentado os consumos de MS e de FDN, não melhorou a utilização da ureia em dietas de bovinos de corte.

We evaluated the effect of the inclusion of zeolite in the diet of beef cattle on the ruminal digestibility, total and partial production of nitrogen, microbial efficiency and blood characteristics. Treatments based on the dietary dry matter (DM) were: 0%, 0.75%, 1.5%, 2.25% and 3.0% of zeolite. We used five crossbred steers fistulated in the rumen and abomasum, fed corn silage and concentrate, representing 65% forage and 35% concentrate. The design was a 5x5 latin square with five periods of 15 days. The animals received 15g of titanium dioxide (TiO2) from the third to the 12th day of each period. A significant effect (P<0.05) on the daily consumption (kg/day) of crude protein (CP) was observed (P<0.05) for DM intake and neutral detergent fiber corrected for ash and protein (NDFap) expressed in g/kg. The total digestibility of total digestible nutrients (TDN) was influenced by treatments (P<0.05). Ruminal digestibility of non-fiber carbohydrates (NFC) was affected quadratically (P<0.05) as well as intestinal CP and NFC. Intake and fecal excretion of nitrogen (g/day) were affected linearly (P<0.05) by adding zeolite. It was concluded that the addition of zeolite in the diet, while increasing the intake of DM and NDF, did not improve the use of urea in the diet of beef cattle.

Ingestão e digestibilidade aparente em ovinos alimentados com silagens de capim-elefante inoculadas com Streptococcus bovis / Intake and apparent digestibility in sheep fed elephant grass silage inoculated with Streptococcus bovis

Foram avaliadas a ingestão e a digestibilidade aparente de silagens de capim, utilizando-se 20 ovinos adultos, sem raça definida, castrados, distribuídos em delineamento inteiramente ao acaso, com quatro tratamentos: silagem de capim-elefante; silagem de capim-elefante inoculada com 10(6)UFC/g de()estirpes de Enterococcus faecium; silagem de capim-elefante inoculada com 10(6)UFC/g de estirpes de Streptococcus bovis JB1; e silagem de capim-elefante inoculada com 10(6)UFC/g de()estirpes de S. bovis HC5, e cinco repetições por tratamento. O período de avaliação foi de 21 dias, sendo 15 para adaptação e seis para as coletas. Observou-se diferença (P<0,05) entre o consumo de matéria seca, sendo a silagem-controle a que apresentou os valores mais baixos - 1,43%PV ou 42,79g/kg PV0,75/dia -, enquanto a silagem inoculada com S. bovis HC5 apresentou o melhor consumo de matéria seca, 2,3% PV ou 56,10g/kg PV0,75/dia. Menores valores de digestibilidade da matéria seca ocorreram na silagem-controle, 42,8% da MS, seguida pela silagem de capim-elefante inoculada com E. faecium e S. bovis JB1. Para a digestibilidade aparente da fibra em detergente neutro, houve efeito dos inoculantes (P<0,05) com valores acima de cinco pontos percentuais em relação à silagem inoculada, 54,7%.

The intake and digestibility were evaluated in grass silage, using 20 adult sheep, mixed breed, distributed in a completely randomized design with four treatments: elephant grass silage without inoculant, elephant grass silage inoculated with 10(6)FCU/g of strains of Enterococcus faecium, elephant grass silage inoculated with 10(6)FCU/g strains of Streptococcus bovis JB1, elephant grass silage inoculated with 10(6)FCU/g of strains of S. bovis HC5 and five replicates per treatment. The evaluation period lasted 21 days being 15 for diet adaptation and six for the collections. There was a statistical difference (P<0.05) between the intake of dry matter of the silages assessed, and the highest values were recorded in the silages inoculated with microbial inoculants. Silage without inoculation had the lowest values (P<0.05) of dry matter intake (1.43% BW or 42.79g/kg BW0,75/day) and silage inoculated with Streptococcus bovis HC5 showed higher dry matter intake (2.3% or 56.10BW g/kg BW0,75/day). The lowest digestibility of dry matter occurred in the control silage (42.8% DM) followed by elephant grass silage inoculated with E. faecium and S. bovis JB1, respectively. The apparent digestibility of neutral detergent fiber was affected by inoculation (P<0.05) with values higher than five percentage points compared to elephant grass silage without inoculant (54.7%).

Hábito de pastejo de vacas lactantes Holandês x Zebu em pastagens de Brachiaria brizantha e Brachiaria decumbens / Grazing behavior of Holstein x Zebu lactating cows in pastures of Brachiaria brizantha and Brachiaria decumbens

Avaliou-se o comportamento ingestivo de pastejo de vacas leiteiras em pastagens de Brachiaria brizantha e Brachiaria decumbens, em sistema de lotação contínua com taxa de lotação variável. O delineamento experimental foi o inteiramente ao acaso, com os dois pastos representando os tratamentos, cada um com cinco repetições. O período experimental foi de 30 dias, sendo 20 para adaptação dos animais e 10 para avaliações, em número de três, com duração de 24h cada, em intervalos de cinco dias. O tempo de pastejo da Brachiaria brizantha foi menor, 10,82h, que o tempo de pastejo da Brachiaria decumbens, 12,86h. Comportamento oposto foi observado para o tempo de ruminação, 7,95 e 6,45h para os pastos de Brachiaria brizantha e Brachiaria decumbens, respectivamente. A quantidade de bocados por minuto foi menor na Brachiaria decumbens, 37,30, e maior na Brachiaria brizantha, 42,12. Houve adequação entre os tempos de pastejo, ruminação e taxa de bocados, de modo que o total de bocados e o tempo de ócio não foram diferentes entre os dois pastos.

The grazing behavior of lactating cows in pastures of Brachiaria brizantha and Brachiaria decumbens, in system of continuous stocking with variable stocking rate was evaluated. A completely randomized experimental design, with two treatments (pastures) and five replicates was used. The experimental period last 30 days, 20 for adaptation of the animals and 10 for three experimental evaluations, of 24h each, in intervals of five days. The grazing time of cows on the Brachiaria brizantha pasture, 10,82h, was lower than on the Brachiaria decumbens, 12,86h. Inverse behavior was observed for rumination time, 7,95 and 6,45h for cows on the pastures of Brachiaria brizantha and Brachiaria decumbens, respectively. The amount of bite per minute was lower for cows on the Brachiaria decumbens, number 37,30h, than on the Brachiaria brizantha, 42,12h. There was an adequacy among grazing time, rumination time and rate of bites and, as a consequence, no difference between pastures was observed for total of bites and time of idling.

Hábito de pastejo de eqüinos em pastagens tropicais de diferentes estruturas / Equine grazing habits in tropical pastures of different structures / Hábito de pastoreo de equinos en pastizales tropicales de diferentes estructuras

As pastagens brasileiras são inúmeras, gerando uma estrutura muito diferenciada entre elas, além do próprio manejo imposto pelo manejador. Em função disso, de fatores climáticos e nutricionais, os eqüinos tem de adaptar-se à frequência de bocados para ingerir o máximo de forragem em um tempo de pastejo que mantenha suas exigências nutricionais. De forma geral, os eqüinos tem um tempo de pastejo entre 12 a 18 horas e uma frequência de bocados entre 23 a 42 bocados por minutos.

The Brazilian pastures are countless and that generates a very different structure among the pastures, besides the own handling imposed by the handler. Because of this, and of climatic and nutritional factors, the equine have to adapt themselves to the frequency of mouthfuls to ingest the maximum of forage in a time of grazing that maintains their nutritional demand. In general, the equine have a time of grazing from 12 to 18 hours and a frequency of mouthfuls from 23 to 42 mouthfuls per minute.

Los pastizales brasileños son diversos, eso genera una estructura muy diferenciada entre los pastizales, además del propio manejo impuesto por el manejador. En función de los factores climáticos y nutricionales, los equinos tienen que adaptarse a la frecuencia de bocados para ingerir el máximo de forraje en un tiempo de pastoreo que mantenga sus exigencias nutricionales. De forma general, los equinos tienen un tiempo de pastoreo entre 12 a 18 horas y una frecuencia de bocados entre 23 a 42 bocados por minuto.