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11.
Ramos Silva JC Marvulo MF Dias RA Ferreira F Amaku M Adania CH Ferreira Neto JS 《Preventive veterinary medicine》2007,78(3-4):286-295
From September 1995 to February 2001, blood samples were collected from 865 neotropical felids belonging to 8 different species. These animals were housed in 86 institutions located in 78 cities of 20 Brazilian states. Our goal was to identify the risk factors associated with sero-positivity to Toxoplasma gondii in captive neotropical felids from Brazil. All serum samples were tested by the modified agglutination test (MAT), using formalin-fixed whole tachyzoites and mercaptoethanol. For each animal an individual questionnaire was filled with questions about tattoo number, felid species, age, sex, origin, number of animals in the group, introduction of new animals in the group, time in the institution, eating meat previously frozen for a period <7 days in the last 6 months, eating meat of run-over or euthanized animals in the last 6 months, predation of rodents or birds in the last 6 months and presence of domestic cats near the enclosures in the last 6 months. The total sero-prevalence was 55% (95% CI: 52%, 57%). We estimated a prevalence of 46% (95% CI: 40%, 54%) for jaguarundi (Puma yagouaroundi); 58% (95% CI: 53%, 63%) for ocelot (Leopardus pardalis); 50% (95% CI: 45%, 56%) for oncilla (L. tigrinus); 54% (95% CI: 46%, 62%) for margay (L. wiedii); 12% (95% CI: 4%, 31%) for Pampas-cat (L. colocolo); 83% (95% CI: 65%, 93%) for Geoffroy's-cat (L. geoffroyi); 64% (95% CI: 50%, 68%) for jaguar (Panthera onca) and 48% (95% CI: 42%, 54%) for puma (Puma concolor). Multiple logistic regression was used to evaluate the association between the variables in the questionnaire and sero-positivity to T. gondii. We concluded that the independent risk factors for toxoplasmosis were: age >3 years (OR = 4.75 [2.75; 8.2]), eating meat previously frozen for a period <7 days (OR = 2.23 [1.24; 4.01]), and consumption of animals that were run-over or euthanized (OR = 1.64; [1.14; 2.37]). 相似文献
12.
Lina Maria Correa E Ricardo D. Moreno José Luis Riveros 《Anatomia, histologia, embryologia》2023,52(2):336-340
This is the first morpho-histological comparison of guanaco ovaries between reproductive (long-days) and non-reproductive (short-days) seasons, and oestrogen receptor-alpha (ERα) and beta (ERβ) detection. Different stages of follicle development were found in the cortical area, but no corpus luteum was detected. The size and frequency of antral follicles and large atretic follicles were higher in long-day ovaries than short-days, consistent with ovarian activity in this season. Differential expression of ERα and ERβ was observed in follicles at different stages of development between short and long days. These data reveal histological and molecular differences between reproductive and non-reproductive seasons of guanaco ovaries. 相似文献
13.
Lasmar Chaim J. Queiroz Antônio C. M. Rosa Clarissa Carvalho Nathália S. Schmidt Fernando A. Solar Ricardo R. C. Paolucci Lucas N. Cuissi Rafael G. Ribas Carla R. 《Landscape Ecology》2021,36(9):2583-2597
Landscape Ecology - Harmful effects of habitat loss and fragmentation can be detected across multiple spatial scales, yet most studies that aim to characterize these effects take place at a single... 相似文献
14.
Robson RV Alves Tatiana Soares Elinaldo FL Bento Ricardo S Roldan‐Filho Brbara SS Souza Marcele KN Lima Jssica S Nascimento Luana CBB Coelho Roberto A S Thmarah A Lima Gabriel GA Gonalves Fbio A Brayner Luiz C Alves Daniela MAF Navarro Thiago H Napoleo Patrícia MG Paiva 《Pest management science》2020,76(2):730-736
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16.
Genetic parameters for spawning and growth traits in the Pacific white shrimp (Penaeus (Litopenaeus) vannamei) 下载免费PDF全文
Alejandra Caballero‐Zamora Eugenia Guadalupe Cienfuegos‐Rivas Hugo H Montaldo Gabriel Ricardo Campos‐Montes Alfonso Martínez‐Ortega Héctor Castillo‐Juárez 《Aquaculture Research》2015,46(4):833-839
The aim of this study was to estimate genetic parameters for spawning traits and growth traits in a breeding line of Pacific white shrimp, Penaeus (Litopenaeus) vannamei, selected for growth and survival. Traits studied were number of eggs (NE) and number of nauplii (NN) and female body weight at insemination (FWI) and body weight at 130 days of age (BW130). Genetic parameters were estimated using a multivariate animal model. Heritability for NE and NN were estimated as 0.13 ± 0.04 and 0.03 ± 0.04 respectively. The contribution to NN total variation due to ‘factors associated with male’ effect was estimated as 0.47 ± 0.07. In the cases of FWI and BW130, heritability was estimated as 0.44 ± 0.08 and 0.19 ± 0.03 respectively. Genetic correlation between FWI and NE was estimated as 0.49 ± 0.15, between FWI and NN as 0.54 ± 0.39 and between NE and NN as 0.27 ± 0.41, whereas the genetic correlations of FWI, NE and NN with BW130 were 0.30 ± 0.13, ?0.21 ± 0.19 and ?0.25 ± 0.38 respectively. Although it is important to perform more studies on this issue, our results found no evidence of a genetic antagonistic effect between female reproductive traits and body weight at harvesting (130 days of age) in P. vannamei. 相似文献
17.
Frederic Vandeperre Ruth M. Higgins Julio Sánchez‐Meca Francesc Maynou Raquel Goñi Pablo Martín‐Sosa Angel Pérez‐Ruzafa Pedro Afonso Iacopo Bertocci Romain Crec’hriou Giovanni D’Anna Mark Dimech Carmelo Dorta Oscar Esparza Jesús M. Falcón Aitor Forcada Ivan Guala Laurence Le Direach Concepción Marcos Celia Ojeda‐Martínez Carlo Pipitone Patrick J. Schembri Vanessa Stelzenmüller Ben Stobart Ricardo S. Santos 《Fish and Fisheries》2011,12(4):412-426
Marine protected areas (MPAs) are often promoted as tools for biodiversity conservation as well as for fisheries management. Despite increasing evidence of their usefulness, questions remain regarding the optimal design of MPAs, in particular concerning their function as fisheries management tools, for which empirical studies are still lacking. Using 28 data sets from seven MPAs in Southern Europe, we developed a meta‐analytical approach to investigate the effects of protection on adjacent fisheries and asking how these effects are influenced by MPA size and age. Southern European MPAs showed clear effects on the surrounding fisheries, on the ‘catch per unit effort’ (CPUE) of target species, but especially on the CPUE of the marketable catch. These effects depended on the time of protection and on the size of the no‐take area. CPUE of both target species and the marketable catch increased gradually by 2–4% per year over a long time period (at least 30 years). The influence of the size of the no‐take area appeared to be more complex. The catch rates of the entire fishery in and around the MPA were higher when the no‐take areas were smaller. Conversely, catch rates of selected fisheries that were expected to benefit most from protection increased when the no‐take area was larger. Our results emphasize the importance of MPA size on its export functions and suggest that an adequate, often extended, time frame be used for the management and the evaluation of effectiveness of MPAs. 相似文献
18.
Ricardo Vieira Rodrigues Luis Alberto Romano Michael Hans Schwarz Brendan Delbos Luís André Sampaio 《Aquaculture Research》2014,45(7):1133-1139
This study evaluated the median lethal concentration values (LC50) and the histopathological effects of un‐ionized ammonia (NH3‐‐N) on juvenile maroon clownfish Premnas biaculeatus. After 96 h of exposure to different concentrations of ammonia, juveniles were sampled for histopathological evaluation. The 24 and 96 h LC50 values of NH3?‐N determined were 1.68 and 0.89 mg L?1 respectively. Maroon clownfish exposed to different ammonia concentrations displayed histopathological alterations in the gills, kidney, liver and brain. Gill tissue damage included lamellar hyperplasia, lamellar shorting and hyperplasia and hypertrophy of mucous cells. The kidney showed hyperanaemia, enlarged sinusoids within an apparently decreased amount of haematopoietic tissue, oedema on tubular cells and tubular necrosis, and an enlarged Bowman's capsule. The liver presented dilatation of hepatic sinusoids, fatty deposition in hepatocytes and Mallory bodies. Examination of the brain revealed a proliferation of glial cells, and the Virchow‐Robin space indicated a severe perivascular oedema and signs of neuronal suffering with satellitosis. The results of this study indicate that juvenile maroon clownfish are relatively sensitive to ammonia and particular attention must be given to this toxic compound in culture systems. 相似文献
19.
Neil J Duncan Leonardo Ibarra-Castro & Ricardo Alvarez-Villaseñor 《Aquaculture Research》2008,39(4):427-433
Spotted rose snapper, Lutjanus guttatus (Steindachner), eggs were incubated under different photoperiods to examine the effect of photoperiod on incubation. The eggs from two fish were incubated under five artificial photoperiods: constant dark (D), constant light (L) from 06:00 hours and 6, 10 and 14 h of light from 06:00 hours. The eggs from seven other fish were incubated under a natural photoperiod. Different spawning times (21:00 – 01:00 hours) and different photoperiods combined to give the start of the dusk photoperiod change after 11–23 h of incubation. Constant light or applying the dusk photoperiod change after ≥20 h of incubation appeared to extend the hatching period. The mean hatching period for groups of eggs incubated in darkness or that received the dusk photoperiod change after ≤19 h of incubation (n=8 different groups) was 2 h 15±10 min, which was significantly lower (P<0.05) than the mean hatching period of 4 h±37 min for groups that did not receive the dusk photoperiod change or that received the dusk photoperiod change after ≥20 h of incubation (n=9 groups). However, despite these differences, the majority of the eggs hatched during a 2–3 h period from 17 to 20 h of incubation, and a sigmoid regression (r2=0.9) explained the relationship between percentage hatch and hours of incubation for all photoperiod groups. 相似文献
20.
Effects of density on growth and survival of juvenile Red Swamp Crayfish, Procambarus clarkii (Girard), reared under laboratory conditions 总被引:2,自引:0,他引:2
Ricardo Oliveira Ramalho Alexandra Marçal Correia & Pedro Manuel Anastácio 《Aquaculture Research》2008,39(6):577-586
The aim of this study was to quantify the importance of population density on the growth and survival of juvenile red swamp crayfish, Procambarus clarkii (Girard), and to understand the effects of density on both the period between moults and the increment per moult at high densities without food limitation. A laboratory experiment was performed to determine growth and survival of juvenile crayfish at five densities (20, 40, 60, 80 and 100 crayfish m?2). Density clearly affected crayfish growth. The impact of density on final weight was higher than on total length increase, growth rate and final length (FL) (by decreasing order of effect). When comparing minimum and maximum densities, we observed that FL suffered a 34% reduction. Number of moults, mean intermoult period (IP) and survival were not significantly affected by density. Our results indicated that the IP and the percentage of increment per moult are affected by the size of crayfish before moult and we provide equations for these relations. Our findings are relevant both for crayfish aquaculture management and for the management of wild or harvested rice‐field crayfish populations. 相似文献