Mortality Rate in Male and Female Guinea-pigs on a Scorbutogenic Diet

Nature ◽  
1973 ◽  
Vol 242 (5399) ◽  
pp. 522-523 ◽  
Author(s):  
M. J. BARNES ◽  
B. J. CONSTABLE ◽  
S. G. IMPEY ◽  
E. KODICEK
Author(s):  
Nancy G. Wehner ◽  
Michael Skov ◽  
George Shopp ◽  
Meredith S. Rocca ◽  
Janet Clarke

2017 ◽  
Vol 24 (3) ◽  
Author(s):  
A Romanova ◽  
O Krasko

Aim of the study: to evaluate the dynamics and to make a comparative analysis of male and female mortality among the population of Belarus Republic during 1959 – 2015.Materials and methods. The data on natural population movement in the Republic of Belarus during 1959 – 2015 have been analyzed in the research work. Crude and standardized mortality rates have been calculated using the direct standardization according to the world standard (Standard “World”), approved by WHO. JoinPoint software was used to investigate time trends as well as office suite MSEXCEL 2010.Results of the study. The minimum values of male and female crude and standardized mortality rates were established in 1964. Throughout the study period, the male population mortality rate grew 1.8-fold (based on crude rates – 2.4-fold), the female population mortality rate – 1.6-fold (based on crude rates – 2.2-fold). During 1985 – 2005, the differences in crude mortality rates among men and women grew 1.2-fold, and during 1962 – 2011, the differences in standardized rates increased 1.8-fold. Since 2003, the mortality rate among men and since 1999, the death rate among women has declined with an annual decrease rate to be more than twice as high as compared to an annual mortality increase registered during its growth.Conclusion. Since the 1960s, the changes in population age structure of the male and female population affected the crude mortality rates. The male and female mortality growth is due to an increased unfavorable impact of combined environmental factors. The adaptive capacity of women to sustain environmental changes contributed to their later entry into the period of mortality growth, as compared to men. The mortality rate reduction in men since 2003 and the excess of a decrease over an increase rate is associated with a set of state measures aimed at protecting and strengthening the public health in the republic.


2014 ◽  
Vol 7 (3) ◽  
pp. 193-198 ◽  
Author(s):  
Solange Ribeiro Peixoto ◽  
José Jurberg

Rhodnius stali Lent, Jurberg & Galvão vetor da Doença de Chagas domiciliado na região do Alto Beni, Bolívia é uma espécie com a biologia pouco conhecida. Com o objetivo de ampliar o conhecimento acerca de sua biologia, observamos parâmetros de seu ciclo de vida, nos estádios de ninfa, comparando-os com Rhodnius pictipes Stål, espécie morfologicamente semelhante e filogeneticamente próxima. Os seguintes parâmetros foram observados: tempo de eclosão dos ovos, ciclo biológico de ovo-adulto (em machos e fêmeas separadamente), taxa de mortalidade, idade do primeiro repasto sanguíneo e volume de sangue ingerido pelas ninfas. De maneira geral observou-se que as R. stali tem um ciclo de vida mais longo do que R. pictipes e, em ambas espécies, o tempo entre a eclosão do ovo até a fase adulta é menor em fêmeas. Curiosamente para R. stali, que é sabidamente capaz de colonizar domicílios, foi observada uma taxa de mortalidade das ninfas mais alta que em R. pictipes, algo inesperado para a espécie que coloniza estruturas artificiais e foi observada em ambiente artificial. Para R. stali, o primeiro repasto sanguíneo ocorreu, em média, quatro dias mais tarde do que em R. pictipes, espécie que ingeriu um volume total de sangue maior, possivelmente pelo fato de seu corpo ser maior. Conhecendo-se com profundidade os aspectos biológicos dessas espécies será possível direcionar o controle vetorial com mais precisão, principalmente em regiões onde colonizam casas, como no Alto Beni, Bolívia. Biology of Rhodnius stali Lent, Jurberg & Galvão and Rhodnius pictipes Stål (Hemiptera, Reduviidae, Triatiminae) in Laboratory Conditions Abstract. Rhodnius stali Lent, Jurberg & Galvão is a Chagas Disease vector that colonize houses in the Alto Beni region, Bolivia and its biology is poorly known. Aiming to enhance the understanding about their biology, we observed a few parameters of its life cycle, at nymphal stages, comparing them with Rhodnius pictipes Stål a morphologically similar and phylogenetically close species. The following parameters were observed: time of hatching, development time from egg to adult (male and female separately), mortality rate, age at first blood meal and blood volume ingested by nymphs. In general, it was observed that the R. stali has longer cycle than R. pictipes, and in both species, the time between hatching the egg to adult in females is lower. Interestingly for R. stali, which is known to be capable of colonizing households, the mortality rate of nymphs was higher than observed in R. pictipes, something unexpected for species that colonize artificial structures and was observed in artificial environment. For R. stali, the first blood meal was, on average, four days later than for R. pictipes, species that ingested a greater total blood volume, possibly because of its bigger size. By knowing in depth the biological aspects of these species it will be possible to direct vector control more accurately, especially in regions where they colonize houses, as in the Alto Beni, Bolivia.


1964 ◽  
Vol 42 (3) ◽  
pp. 367-385 ◽  
Author(s):  
Reino S. Freeman

Male and female mice developed a leucocytosis in peritoneal fluid and blood after intraperitoneal injection with cysticerci of Taenia crassiceps. Free mast cells declined intraperitoneally from normal range of 650 to 1500 cells per cu. mm to less than 100 per cu. mm; eosinophils increased from less than 100 per cu. mm to 95,000 per cu. mm, with a logarithmic rise during the first 1 to 2 weeks in mice overcoming the cysticerci. Cells of the monocyte–lymphocyte series also increased intraperitoneally, but heterophils remained scarce. Leucocytosis and eosinophilia were most pronounced in mice just overcoming cysticerci, less when cysticerci were alive, and least when cysticerci were overcome. Males generally developed higher eosinophilia faster than females and overcame cysticerci more successfully. Females which were fed eggs developed peripheral eosinopenia during the first 2 weeks, then changed to an eosinophilia without concomitant leucocytosis. Those mice which develop high eosinophilia quickly overcome injected cysticerci most successfully. Female mice with intraperitoneal cysticerci showed strong resistance against challenge feedings of eggs 28 days later, but were less resistant after only 14 days. Mate and female guinea pigs, which are refractory to intraperitoneally injected cysticerci, developed a blood eosinophilia, and eosinophilia and leucocytosis in the peritoneal fluid. No free mast cells were seen.


1966 ◽  
Vol 66 (1) ◽  
pp. 97-100 ◽  
Author(s):  
J. C. M. Trail ◽  
G. D. Sacker

1. The effects of birth weight, sex, twinning, parity of dam and dry season on mortality rates of lambs were studied between birth and weaning at 20 weeks in a flock of East African Blackheaded sheep.2. The mean birth weights of non-surviving lambs were lower than those of surviving lambs. Singles from gimmers and twins from ewes were 0.5 and 1.0 lb., respectively, lighter at birth, and had higher mortality rates than singles from ewes. The overall mortality rate of singles from ewes was 16%, singles from gimmers 20% and twins from ewes 28%. Male and female lambs born alive had similar mortality rates (18%).


1974 ◽  
Vol 63 (3) ◽  
pp. 483-488 ◽  
Author(s):  
M. DALLE ◽  
P. DELOST

SUMMARY Concentrations of cortisol and corticosterone in the plasma and adrenal glands of male and female guinea-pigs were estimated throughout the first postnatal day and thereafter at intervals up to 3 weeks of age. In the guinea-pig, the basal level of cortisol secretion is established more slowly than in other species. The concentration of plasma cortisol is very high at birth, with a marked fall between days 1 and 10 post partum and then a steady level from day 10 to 20, the time of weaning. At day 10 the values for plasma cortisol and corticosterone approach the lower ones found in the adult. There were peaks in the amounts of corticosteroids found in the adrenal gland at 50 h, 4 and 7 days and these may have been due to increased hormonal synthesis between days 2 and 8.


2007 ◽  
Vol 42 (2) ◽  
pp. 357-366 ◽  
Author(s):  
Judith Brouillette ◽  
Marie-Andrée Lupien ◽  
Chantale St-Michel ◽  
Céline Fiset

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