Trabajos originales Preferencia termal de machos adultos de Cryphiops caementarius previamente aclimatados a diferen- tes temperaturas / Thermal preference of adult males of Cryphiops caementarius previously acclimated at different temperatures

Resumen El objetivo fue determinar la preferencia termal de machos adultos de Cryphiops caementarius previamente aclimatados a diferentes temperaturas. Los camarones se colectaron del río Pativilca. En laboratorio, los camarones se aclimataron durante 30 días en nueve acuarios, cada uno con 10 recipientes circulares. En cada recipiente hubo un camarón (10 por acuario). Las temperaturas de aclimatación fueron de 19, 24 y 28 °C. El sistema de gradiente de temperatura (12 a 33 °C) fue una canaleta de PVC (3 m de longitud y 10 cm de profundidad) con 18 compartimentos. En un extremo de la canaleta se colocaron termorreguladores sumergibles (100W) y en el otro extremo, bolsas con hidrogel congeladas. La preferencia termal se determinó por el método agudo y las pruebas se realizaron entre las 08:00 y 14:00 h. Los camarones aclimatados a 24 °C se desplazaron a compartimentos cuyas temperaturas fueron más altas que la temperatura de aclimatación. Los camarones aclimatados a 24 °C se desplazaron a compartimentos cuyas temperaturas fueron alrededor de la temperatura de aclimatación. Los camarones aclimatados a 28 °C se desplazaron a compartimentos donde las temperaturas fueron más bajas que aquella de aclimatación. La preferencia termal de los camarones aclimatados a 19 °C fue de 22.7 °C, y la de los aclimatados a 24 °C fue de 24.8 °C, ambos sin diferencias significativas (p>0.05). En cambio, en los aclimatados a 28°C fue de 21.1 °C, que solo difirió (p<0.05) con los aclimatados a 19 °C. La preferencia termal final fue de 24.5 °C.

Abstract In this work, we establish the thermal preference of Cryphiops caementarius adult males, previously acclimated at different temperatures. Shrimp were collected from the Pativilca River. In the laboratory, shrimp were acclimated for 30 days in nine aquariums, each with 10 circular containers. In each container, there was a shrimp (10 per aquarium). Acclimation temperatures were 19, 24 and 28 °C. The gradient temperature system (12 to 33 °C) consisted for a PVC gutter (3 m long and 10 cm deep) with 18 compartments. Submersible thermoregulators (100W) were placed at one end of the gutter and the other end, frozen hydrogel bags. The thermal preference was determined by the acute method and the tests were performed between 08:00 and 14:00 h. Shrimp acclimated at 24 °C moved to compartments whose temperatures were higher than the acclimation temperature. Shrimp acclimated at 24 °C moved to compartments whose temperatures were around the acclimation temperature. Shrimp acclimated at 28 °C moved to compartments where temperatures were lower than acclimation. The thermal preference of acclimated shrimp at 19 °C was 22.7 °C, and those acclimated at 24 °C were 24.8 °C, both without significant differences (p>0.05). On the other hand, in acclimated ones at 28 °C it was 21.1 °C, which only differed (p<0.05) with those acclimated at 19 °C. The final thermal preference was 24.5 °C.

Microfiltración apical entre dos cementos de obturación: biocerámico y resinoso en premolares unirradiculares preparadas con protaper, y obturadas con condensación lateral / Apical microfiltration between two filling cements: bioceramic and resinous in unirradicular premolars prepared with protaper and sealed with lateral condensation

Resumen Objetivo: Comparar in vitro la microfiltración apical en premolares unirradiculares obturados con cemento a base de resina epóxica y cemento biocerámico. Método: 40 piezas dentales unirradiculares fueron seleccionadas y divididas en dos grupos para ser obturadas esperando el tiempo de fraguado de acuerdo con las instrucciones del fabricante. El grupo A se obturó con cemento biocerámico Endosequence y, el grupo B, con cemento a base de resina epóxica AH-Plus: posteriormente los dos grupos fueron sellados con barniz de uñas hasta 3mm de la parte apical, luego se colocaron las muestras en la incubadora a 37ºC. Ambos fueron sometidos a 750 ciclos de termociclado, para reproducir el ambiente parecido a la cavidad oral. Para análisis de microfiltración se utilizó el método de difusión del colorante, se sumergieron en azul de metileno al 2 % por 6 días, posteriormente los especímenes fueron sometidos en una bomba de vacío. Los dientes fueron cortados longitudinalmente para ser evaluadas mediante el estereomicroscopio. El análisis estadístico fue hecho mediante T-Student y Chi-Cuadrado. Resultados: El grupo A corresponde a Endosequence obtuvo una medida de 0,55mm y el grupo B corresponde a AH-Plus 1,20mm con un estimado de significancia de p=0,013. Conclusión: El análisis de ambos cementos de obturación demostró que Endosequence posee menor microfiltración apical que AH-Plus.

Abstract Aim: To compare in vitro by the stereomiscroscope the lesser apical microfiltration in uniradicular premolars, between the cement based on Epoxy Resin and Bioceramic cement. Method: The study was performed on 40 uniradicular dental pieces divided into two groups, the samples were prepared using the protaper system and the obturation was performed using the lateral condensation technique, the first group was sealed withEndosequence bioceramic cement and the second group with Cement based on AH-Plus epoxy resin, then sealed with nail varnish up to 3mm from the apical part, then the samples were placed in the incubator at 37ºC, waiting for the set time corresponding to each group according to the manufacturer's instructions . The two groups of the present study were submitted to 750 cycles of thermocycling, to provide an environment similar to the oral cavity, then longitudinal cuts were made to the samples. The microfiltration was evaluated using the dye diffusion method, immersed in 2% methylene blue for 6 days, then the specimens were subjected to a vacuum pump. The teeth were cut longitudinally to be evaluated by the stereomicroscope. The statistical analysis was through T-Student and Chi-Square. Results: Group A corresponds to Endosequence obtained a mean of 0,55mm and Group B corresponds to AH-Plus 1,20mm with an estimated significance of p = 0,013. Conclusion: Both obturation cements have significant differences, therefore Endosequence has less apical microfiltration than AHPlus.

Características termorreguladoras no início da gestação e índices reprodutivos de matrizes suínas de diferentes ordens de parto / Thermoregulatory characteristics in early pregnancy and reproductive efficiency of sows of different parity orders

Neste estudo objetivou-se avaliar algumas características termorreguladoras no início da gestação, bem como obter alguns índices reprodutivos de matrizes suínas de diferentes ordens de parto. Matrizes de 0 a 11ª ordem de parto (98) foram divididas em nulíparas, primíparas, de segundo ao sexto parto e do sétimo ao décimo primeiro para quantificar a frequência respiratória, temperatura retal e temperatura da pele em três momentos da gestação: no dia da primeira inseminação artificial, do segundo ao quarto dia de gestação e do décimo ao décimo terceiro dia. Também calcularam-se os gradientes térmicos entre temperaturas retal e da pele (TR-TP), temperaturas retal e do ar (TR-TA) e temperaturas da pele e do ar (TP-TA). Outras 164 matrizes de 1ª a 12ª ordens de parto: primíparas, de segundo parto, do terceiro ao sétimo e do oitavo ao décimo segundo parto foram utilizadas para obter o período de gestação e número de leitões nascidos vivos. Os diferentes momentos da gestação e ordem de parto não influenciaram as médias da frequência respiratória e da temperatura da pele. Matrizes de 7ª a 11ª ordem de parto apresentaram menor média de temperatura retal que as demais ordens. Em relação aos momentos da gestação, foi observada menor temperatura retal do segundo ao quarto dia de gestação comparado ao dia da primeira inseminação e do décimo ao décimo terceiro dia de gestação. O gradiente TR-TP de leitoas foi maior em comparação às demais ordens de parto. Matrizes de 7ª a 11ª ordem de parto apresentaram valores dos gradientes TR-TA e TP-TA maiores em relação às demais ordens de parto. O gradiente TR-TP aumentou conforme se distanciou do dia da inseminação artificial e os gradientes TR-TA e TP-TA, diminuíram. Matrizes de 8ª a 12ª ordem de parto apresentaram maior período de gestação (114,87±1,55 dias) comparada aos demais grupos de ordem de parto (113,28±1,43 para primíparas; 113,09±1,77 para 2º parto e 113,83±1,33 dias para 3º ao 7º). O número de leitões nascidos vivos não diferiu entre as diferentes ordens de parto. Momentos da gestação até o 13º dia e a ordem de parto não influenciam a temperatura da pele medida pela manhã e a frequência respiratória avaliada às 14 horas. Entretanto, matrizes suínas mais velhas (7ª a 11ª ordem de parto) apresentam menor temperatura retal pela manhã e maior período de gestação. A ordem de parto não interfere no número de nascidos vivos na linhagem comercial PenArlan.

The aim of this study was to evaluate some of the thermoregulation characteristics during early pregnancy, and obtain reproductive parameters of sows of different birth orders. Sows 0-11 the parity orders (98) were divided into groups consisting of nulliparous; primiparous; sows from the second to sixth; and sows from the seventh to eleventh birth, in order to quantify the respiratory rate, rectal temperature and skin temperature at three time intervals of pregnancy: the day of first artificial insemination, the second to the fourth day of gestation and the tenth to the thirteenth day. The thermal gradients between rectal and skin temperatures (RT-ST), rectal temperatures and air (RT-AT) and skin temperatures and air (ST-AT) were also calculated. Another 164 sows from 1st to 12th parity orders were grouped as follows: primiparous, second parity, the third to the seventh, and the eighth to twelfth parity orders were used to obtain data on gestation period and number of piglets born alive. The different stages of gestation and parity orders did not influence the average respiratory rate and skin temperature. Sows of 7th to 11th parity orders showed lower mean rectal temperature than the other orders. As regards gestation times, lower rectal temperature was observed on second to fourth day of gestation compared with the first day of insemination and the tenth to the thirteenth day of gestation. The RT-ST gradient of gilts was higher compared with that of other parity orders. Sows of groups from 7th to 11th parity orders showed higher values of gradients RT-AT and ST-AT compared with other parity orders. The RT-ST gradient increased as time passed after the day of insemination, and RT-AT and ST-AT gradients decreased. Sows from 8th to 12th parity orders showed longer gestation period (114.87 ± 1.55 days) compared with the other groups of parity order (113.28 ± 1.43 for primiparous; 113.09 ± 1.77 to 2nd parity orders and 113.83 ± 1.33 days for the group from 3rd to 7th parity orders. The number of piglets born alive did not differ between the different parity orders. Time intervals of pregnancy until the 13th day and the parity orders did not influence the skin temperature measured in the morning, and respiratory rate measured at 14 hours. However, older sows (7th to 11th parity order) had a lower rectal temperature in the morning and longer gestation period. The parity order did not interfere in the number of live births in the commercial line PenArlan.