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81.
Otolith geochemistry in young‐of‐the‐year peacock bass Cichla temensis for investigating natal dispersal in the Rio Negro (Amazon – Brazil) river system
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Raniere C. S. Garcez Robert Humston David Harbor Carlos E. C. Freitas 《Ecology of Freshwater Fish》2015,24(2):242-251
This study examined otolith geochemistry as a natural marker of natal origins in young‐of‐the‐year (YOY) Cichla temensis in the Negro River Basin of Brazil. We analysed trace element and isotopic composition of otoliths of YOY collected off spawning nests from the main stem and major tributaries. These were compared with regional bedrock geologic composition to explore underlying mechanisms of differences in otolith geochemistry. Our results suggest that spatial differences in otolith geochemistry can be used to distinguish natal origins based on 87Sr/86Sr, Sr/Ca and Ba/Ca ratios. This approach allowed us to correctly classify 99% of juvenile fish to their natal streams using cross‐validation in a linear discriminant function analysis (LDFA). Patterns of otolith isotopic composition correspond with patterns in regional geology as expected based on previously demonstrated correlations, although some fine‐scale spatial differences cannot be accounted for by available geologic information. These results demonstrate that otolith chemistry is valuable as a natural marker of natal origins in this system and suggest that inferences from geologic maps may be useful for interpreting movements based on otolith geochemical signatures. This information provides the basis for future work to investigate the early life history and spatial ecology of this important cichlid. 相似文献
82.
Zanoni JN De Freitas P Pereira RV Dos Santos Pereira MA De Miranda Neto MH 《Anatomia, histologia, embryologia》2005,34(3):149-153
We investigated the effect of ascorbic acid (AA) supplementation on the NADPH-diaphorase (NADPHd) and myosin-V myenteric neurons in the ileum of rats, after 4 months of treatment. Two groups were compared, i.e. controls rats (C) and AA-treated rats (CA). Myosin-V immunohistochemistry and NADPHd histochemistry were employed. We investigated the areas of 500 cell bodies of myosin-V neurons and of 500 NADPHd stained neurons from all groups. The quantitative analysis was performed using an area of 8.96 mm2 from each ileum. There was an increase of 21.9% in the myosin-V immunoreactive myenteric neurons (P > 0.05) and of 22.5% in the NADPHd in group CA when compared with C (P < 0.05). There were no significant differences when we compared the area of myosin-V stained neurons between groups C and CA. However, we verified an area reduction of 7.5% in NADPHd neurons when comparing group C to group CA (P < 0.05). 相似文献
83.
Buzinaro MG Freitas PP Kisiellius JJ Ueda M Jerez JA 《Veterinary journal (London, England : 1997)》2003,166(2):185-187
To determine the incidence of rotavirus infection among dairy herds in the State of S?o Paulo, Brazil, 576 faecal samples obtained from calves aged 1-45 days with and without diarrhoea, reared on 63 dairy cattle farms, were analyzed. Polyacrylamide gel electrophoresis (PAGE) identified 28 samples positive for group A rotavirus, while four samples, two diarrhoeic and two non-diarrhoeic, showed a bisegmented genome with a typical picobirnavirus pattern. Electron microscopy revealed spherical virus particles with a diameter of 37 nm and without a defined surface structure. The present study is the first report of a bisegmented virus identified in cattle in Brazil. 相似文献
84.
Chagas AC Vieira LS Freitas AR Araújo MR Araújo-Filho JA Araguão WR Navarro AM 《Veterinary parasitology》2008,151(1):68-73
Gastrointestinal nematodes are becoming increasingly resistant to the commercial products used to control them. The cost of routine vermifuge applications on herds and the problem of residues in animal products and the environment have prompted research on the anthelmintic activity of plant extracts. This work examines the anthelmintic action of neem and the homeopathic product Fator Vermes in sheep kept in a pasture for 18 months. Forty sheep of the Morada Nova breed were divided into four treatments and the control, according to the EPG. During the experiment, each animal received 100 g/day of shredded corn and did not receive protein supplementation. In treatment 1 (control), the animals received only shredded corn. Treatment 2 received 1.6 g/(animal day) of the homeopathic product mixed with the shredded corn, and treatments 3, 4 and 5 received, respectively, 12.5, 25.0 and 37.5 g/(animal day) of dried Azadirachta indica leaves mixed with the shredded corn. The neem was administered for alternating 15-day periods and the homeopathic product daily for 18 months. There were 39 fortnightly fecal collections made to count the EPG, and fecal cultures were performed monthly. The following genera, in percentage, were identified: Haemonchus: 65.58+/-3.27, Trichostrongylus: 15.92+/-7.38 and Oesophagostomum: 18.50+/-6.22. The treatments evaluated were not effective in controlling gastrointestinal nematodes (P>0.05), whose mean log(10) counts (EPG +1) and standard errors for treatments 1-5 were respectively 3.55+/-0.28; 3.48+/-0.31; 3.90+/-0.29; 2.78+/-0.29 and 3.48+/-0.30. A significant effect (P<0.0001) was observed of the periods of the year when the 39 collections occurred. Because of the diet deficient in raw protein, the sheep had higher average EPG counts, for all the treatments, at the end of the dry season, and the opposite occurred in the middle of the rainy season. 相似文献
85.
Quinelato S Couto MC Ribeiro BC Santos CN de Souza LS Dos Anjos DH Sampaio IB Rodrigues LM 《Veterinary parasitology》2008,153(1-2):100-107
Experimental studies about the recovery, survival and migration to pasture of cyathostomin infective larvae (L(3)) from fresh feces depositions were conducted from February 2005 to March 2007 in a tropical region of southeast Brazil. Grass and feces were collected weekly at 8 a.m., 1 and 5 p.m. and processed by the Baermann technique. Multivariate analysis (principal components method) showed the influence of time and environmental variables on the number of infective larvae recovered from the feces and pasture. In the rainy period (October-March), more infective larvae were recovered on the feces and grass apex. In contrast, in the dry period (April-September), the recovery was higher only on the grass base, as well as the L(3) survival on feces and grass. More larvae were recovered at 8 a.m., except from the grass apex, where the highest recovery was at 1 p.m. Few studies investigating the seasonal transmission of equine cyathostomin have been conducted in South American tropical climates. These results demonstrate that in tropical conditions L(3) are available on feces and pasture throughout the year. Knowledge of climatic influences on the development and survival of L(3) is crucial to designing integrated parasite control programs that provide effective protection while slowing the development of anthelmintic resistance. 相似文献
86.
Claudia C. Medugno Jos M. G. Ferraz Aline de H. N. Maia Cludio C. L. Freitas 《Pest management science》1997,51(2):153-156
The influence of different carriers on the physical and biological stability of Baculovirus anticarsia wettable powder formulations was studied. The formulations were obtained by mixing the purified polyhedra of B. anticarsia with a carrier and drying the suspension in a bench spray dryer. Bioassays with Anticarsia gemmatalis Hübner showed that activity was maintained with the amorphous silica, attapulgite and kaolinite after a year of storage. In the presence of bentonite, activity declined 50% in the same period. All formulations, except kaolinite, maintained the physical parameters required of a good wettable powder. Kaolinite formulation showed reduction in wettability and particle agglomeration in storage. © 1997 SCI 相似文献
87.
88.
Adriano Carvalho Costa Hortência Aparecida Botelho Richardson Cesar da Silva Gomes Sergio Augusto de Sousa Campos Rafael Vilhena Reis Neto Marcio Balestre Fernanda Dotti do Prado Diogo Teruo Hashimoto Diego Galetti Martins Fbio Porto‐Foresti Mrio Lima Rilke Tadeu Fonseca de Freitas 《Aquaculture Research》2019,50(3):717-724
This work was carried out to predict the combining abilities, both general and specific, for performance traits and bodily yields of Serrasalmidae. Ninety‐six 30‐day‐old juveniles were purchased from two commercial fish farms, 12 of each of the following eight genetic groups: pacu, pirapitinga, tambaqui, tambacu, tambatinga, patinga, paqui and piraqui. Six fish from each genetic group were grown in 500‐L fibreglass tanks (two tanks per genetic group) until they were 495 days old. At the end of the growth period fish were weighed, subjected to morphometric analysis and processed to obtain their bodily yields. Two nuclear markers and one mitochondrial marker were used to confirm the identity of the animals. Combining abilities were obtained using the method proposed by Griffing in 1956 (Australian Journal of Biological Science, 4, 463–493) adapted to a mixed models analysis, environmental effects were estimated by the empirical best linear unbiased estimator method and genetic effects (general and specific combining abilities) were estimated with the empirical best linear unbiased predictor. Predictions of the combining abilities of advanced hybrids were obtained by the mixed models mixture method with normal distributions. Tambaqui showed higher general and specific combining abilities than the other groups for most of the variables, making it the most important genetic group. General combining ability makes a greater contribution to phenotypic variance than specific combining ability for most variables, indicating a predominance of genes with an additive effect in the control of evaluated traits. 相似文献
89.
Yugo Moraes Pastrana Danilo Pedro Streit Raycon Roberto Freitas Garcia Bruno Silveira Becker Jos Luiz Rodrigues Leandro Godoy 《Aquaculture Research》2019,50(2):521-528
Our study assessed the efficiency of a formulated new extender in maintaining viability and morphological integrity of Colossoma macropomum spermatozoa under chilling storage. Semen was diluted in the test extender and BTS? (Beltsville Thawing Solution) and exposed to a short‐term storage at 4.6 ± 0.6°C for 96 hr. Both extenders were able to maintain 17% ± 8% motile spermatozoa by the end of experiment. Sperm dilution in test extender did not affect the morphologically normal cells (61% ± 6%) up to 48 hr of chilling, being higher than in BTS? (50% ± 6%) (p < 0.05). After 96 hr, samples kept in the test extender had 50% of normal spermatozoa, whereas those kept in BTS? presented only 38% of normal cells. Chilling storage increased the incidence of cells with strongly coiled flagella in BTS?. Our study is the first to evaluate in detail the spermatozoa morphology as indicative of C. macropomum semen viability. The new extender was able to protect the spermatozoa against increase in coiled flagellum injuries. 相似文献
90.
Barros Lílian Moreira Prochnow Daiane de Oliveira Victoria Freitas da Silva Airton Rosa de Oliveira Antonio Costa da Maia Luciano Carlos 《Journal of Crop Science and Biotechnology》2019,22(1):31-36
Journal of Crop Science and Biotechnology - The morphological characterization allows one to estimate and evaluate the genetic distance among different varieties, identifying heterotrophic groups... 相似文献