Quenching of chlorophyll fluorescence induced by silver nanoparticles

The interaction between chlorophyll (Chl) and silver nanoparticles (AgNPs) was evaluated by analyzing the optical behavior of Chl molecules surrounded by different concentrations of AgNPs (10, 60, and 100 nm of diameter). UV–Vis absorption, steady state and time-resolved fluorescence measurements were performed for Chl in the presence and absence of these nanoparticles. AgNPs strongly suppressed the Chl fluorescence intensity at 678 nm. The Stern-Volmer constant (KSV) showed that fluorescence suppression is driven by the dynamic quenching process. In particular, KSV was nanoparticle size-dependent with an exponential decrease as a function of the nanoparticle diameter. Finally, changes in the Chl fluorescence lifetime in the presence of nanoparticles demonstrated that the fluorescence quenching may be induced by the excited electron transfer from the Chl molecules to the metal nanoparticles

Heat Loss In One Day Old Pullets Inside A Hatchery

After hatching, pullets are transported to brooding area and vaccinated. One day old chicks have not already developed thermoregulation ability; thus, brooding temperature variations may affect pullet quality leading to broiler meat production losses. This research aimed to calculate sensible heat loss in one day old pullets in hatching area and vaccination room. Ten one day old pullets were randomly selected from hatching area of a commercial hatchery. Infrared images were used to calculate bird surface temperature. Exposure areas for the two conditions were quantified, and both air temperature and wind speed was recorded. Total sensible heat loss was calculated as heat loss by radiation plus heat loss by convection. It was found that heat transfer occurs in different ways at different bird body parts. Total heat loss found for hatching baskets was equivalent to 0.81 J s-1 while for vaccination room was 1.16 J s-1. Pullet nutrition is based on energy loss from brooding to farm, and the overall pullet heat loss from hatchery to farm accepted is 13.95 J s-1. Thus, "starter feed" has relevant excess of energy input. These findings indicate that less energy can be used in initial feed, once heat loss is lower than assumed nowadays. Improved knowledge on these conditions may enhance broiler farm feeding strategies and economics during first rearing week.344610616Abreu, P.G., Abreu, V.M.N., Coldebella, A., Hassamer, M.J., Tomazelli, I.L., Medidas morfológicas em função do peso e da idade da ave, por meio de imagens (2012) Revista Brasileira de Engenharia Agrícola e Ambiental, 16 (7), pp. 795-801. , Campinas GrandeAksit, M., Yalçin, S., Yenisey, C., Ozdemir, D., Brooding temperatures for chicks acclimated to heat during incubation: effects on post-hatch intestinal development and body weight under heat stress (2010) British Poultry Science, 51 (3), pp. 444-452. , BristolBaarendse, P.J.J., Kemp, B., Van Den Brand, H., Early age housing temperature affects subsequent broiler chicken performance. (2006) British Poultry Science, 47 (2), pp. 125-130. , BristolBaracho, M.S., Nääs, I.A., Gigli, A.C.S., Impacto das variáveis ambientais em incubatório de estágio múltiplo de frangos de corte (2010) Engenharia Agrícola, 30 (4), pp. 563-577. , JaboticabalCamargo, J.R., (2011) Ambiência pré-porteira: o tempo de espera no incubatório e sua influência sobre o desempenho inicial de frangos de corte., , 98 f. Dissertation (Master in Biossystems Engineering) - Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Piracicaba, 2011Cangar, O., Aerts, J.M., Buyse, J., Berckmans, D., Quantification of the spatial distribution of surface temperatures of broilers. (2008) Poultry Science, 87 (4), pp. 2493-2499. , ChampaignCardoso, A.L.S.P., Avaliação da qualidade sanitária de incubatório por meio de placas de sedimentação (2009) Arquivos do Instituto Biológico, 76 (2), pp. 279-283. , São PauloCordeiro, M.B., Tinôco, I.F.F., Silva, J.N., Vigoderis, R.B., Pinto, F.A.C., Cecon, P.R., Conforto térmico e desempenho de pintos de corte submetidos a diferentes sistemas de aquecimento no período de inverno. (2010) Revista Brasileira de Zootecnia, 39 (1), pp. 217-224. , Viçosa-MGEdgar, J.L., Nicol, C.J., Pugh, C.A., Paul, E.S., Surface temperature changes in response to handling in domestic chickens. (2013) Physiology & Behavior, 119 (2), pp. 195-200. , ElmsfordFerreira, V.M.O.S., Francisco, N.S., Belloni, M., Aguirre, G.M.Z., Caldara, F.R., Nääs, I.A., Garcia, R.G., Polycarpo, G.V., Infrared thermography applied to the evaluation of metabolic heat loss of chicks fed with different energy densities (2011) Brazilian Journal of Poultry Science, 13 (2), pp. 113-118. , CampinasHauvik, L.E., Mercer, J.B., Thermographic mapping of the skin surface of the head in bald-headed male subjects. (2012) Journal of Thermal Biology, 37 (7), pp. 510-516. , AmsterdamHayashi, R.M., (2011) Estudo do sistema imunológico e do trato gastrintestinal de frangos de corte nascidos em diferentes períodos em uma mesma incubadora., , 89 f. Dissertação (Mestrado) - Universidade Federal do Paraná, Curitiba, 2011Lauvers, G., Ferreira, V.P.A., Fatores que afetam a qualidade dos pintos de um dia, desde a incubação até recebimento na granja (2011) Revista Científica Eletrônica de Medicina Veterinária, 9 (16), pp. 1-19. , CuritibaAbreu, P.G., Abreu, V.M.N., Coldebella, A., Hassamer, M.J., Tomazelli, I.L., Medidas morfológicas em função do peso e da idade da ave, por meio de imagens (2012) Revista Brasileira de Engenharia Agrícola e Ambiental, 16 (7), pp. 795-801. , Campinas GrandeAksit, M., Yalçin, S., Yenisey, C., Ozdemir, D., Brooding temperatures for chicks acclimated to heat during incubation: effects on post-hatch intestinal development and body weight under heat stress (2010) British Poultry Science, 51 (3), pp. 444-452. , BristolBaarendse, P.J.J., Kemp, B., Van Den Brand, H., Early age housing temperature affects subsequent broiler chicken performance. (2006) British Poultry Science, 47 (2), pp. 125-130. , BristolBaracho, M.S., Nääs, I.A., Gigli, A.C.S., Impacto das variáveis ambientais em incubatório de estágio múltiplo de frangos de corte (2010) Engenharia Agrícola, 30 (4), pp. 563-577. , JaboticabalCamargo, J.R., (2011) Ambiência pré-porteira: o tempo de espera no incubatório e sua influência sobre o desempenho inicial de frangos de corte., , 98 f. Dissertation (Master in Biossystems Engineering) - Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Piracicaba, 2011Cangar, O., Aerts, J.M., Buyse, J., Berckmans, D., Quantification of the spatial distribution of surface temperatures of broilers. (2008) Poultry Science, 87 (4), pp. 2493-2499. , ChampaignCardoso, A.L.S.P., Avaliação da qualidade sanitária de incubatório por meio de placas de sedimentação (2009) Arquivos do Instituto Biológico, 76 (2), pp. 279-283. , São PauloCordeiro, M.B., Tinôco, I.F.F., Silva, J.N., Vigoderis, R.B., Pinto, F.A.C., Cecon, P.R., Conforto térmico e desempenho de pintos de corte submetidos a diferentes sistemas de aquecimento no período de inverno. (2010) Revista Brasileira de Zootecnia, 39 (1), pp. 217-224. , Viçosa-MGEdgar, J.L., Nicol, C.J., Pugh, C.A., Paul, E.S, Surface temperature changes in response to handling in domestic chickens. (2013) Physiology & Behavior, 119 (2), pp. 195-200. , ElmsfordFerreira, V.M.O.S., Francisco, N.S., Belloni, M., Aguirre, G.M.Z., Caldara, F.R., Nääs, I.A., Garcia, R.G., Polycarpo, G.V., Infrared thermography applied to the evaluation of metabolic heat loss of chicks fed with different energy densities (2011) Brazilian Journal of Poultry Science, 13 (2), pp. 113-118. , CampinasHauvik, L.E., Mercer, J.B, Thermographic mapping of the skin surface of the head in bald-headed male subjects. (2012) Journal of Thermal Biology, 37 (7), pp. 510-516. , AmsterdamHayashi, R.M., (2011) Estudo do sistema imunológico e do trato gastrintestinal de frangos de corte nascidos em diferentes períodos em uma mesma incubadora., , 89 f. Dissertação (Mestrado) - Universidade Federal do Paraná, Curitiba, 2011Lauvers, G., Ferreira, V.P.A., Fatores que afetam a qualidade dos pintos de um dia, desde a incubação até recebimento na granja (2011) Revista Científica Eletrônica de Medicina Veterinária, 9 (16), pp. 1-19. , CuritibaLeksrisompong, N., Romero-Sanchez, H., Plumstead, P.W., Brannan, K.E., Yahav, S., Brake, J., Broiler incubation. 2. Interaction of incubation and brooding temperature on broiler chick feed consumption and growth. 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(2010) Scientia Agricola, 67 (5), pp. 497-502. , PiracicabaNascimento, G.R., Nääs, I.A., Pereira, D.F., Baracho, M.S., Garcia, R., Assessment of broiler surface temperature variation when exposed to different air temperatures. (2011) Brazilian Journal of Poultry Science, 13 (4), pp. 259-263. , CampinasNascimento, G.R., Pereira, D.F., Nääs, I.A., Rodrigues, L.H.A., Índice fuzzy de conforto térmico para frangos de corte. (2011) Engenharia Agrícola, 31 (2), pp. 219-229. , JaboticabalNeves, D.P., Romanini, C.E.B., Nascimento, G.R., Nääs, I.A., Menezes, A.G., Estimativa da perda de calor em pintos de um dia dentro do incubatório. (2009) CONGRESSO BRASILEIRO DE ENGENHARIA AGRÍCOLA, 38. , Juazeiro. Anais. Jaboticabal: Associação Brasileira de Engenharia Agrícola, 2009. 1 CD-ROMItsan, Z., En-Avraham, G., Zoref, Z., Nir, I., Growth and development of digestive organs and some enzymes in broiler chicks after hatching. (1991) British Poultry Science, 32, pp. 23-515. , BristolSouza, V.L.F., Buranelo, G.S., Gasparino, E., Cardozo, R.M., Barbosa, M.J.B., Efeito da automatização nas diferentes estações do ano sobre os parâmetros de desempenho, rendimento e qualidade da carne de frangos de corte. (2010) Acta Scientiarum- Animal Sciences, 32 (2), pp. 175-181. , MaringáTzschentke, B., Plagemann, A., Imprinting and critical periods in early development. (2006) World's Poultry Science Journal, 62 (4), pp. 626-637. , CambridgeVieira, S.L., Digestão e utilização de nutrientes após a eclosão de frangos de corte. (2004) SIMPÓSIO BRASIL SUL DE AVICULTURA, 5, pp. 26-41. , Chapecó. AnaisYahav, S., Straschnow, A., Luger, D., Shinder, D., Tanny, J., Cohen, S., Ventilation, sensible heat loss, broiler energy, and water balance under harsh environmental conditions (2004) Poultry Science, 83 (2), pp. 253-258. , Champaig