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91.
Fátima Carvalho Paula Lima Fernando Gonçalves Fernanda Russell-Pinto Jorge Machado 《Journal of the World Aquaculture Society》2004,35(2):189-198
Selenastrum, Chlorella and the Cyanophyta groups, important components of the phytoplankton in the natural habitat of Anodonta cygnea in Mira Lagoon, were used separately as experimental diet for Anodonta cygnea. To assess the effects of the different diets, several organic and inorganic compounds of the haemolymph and extrapallial fluid were measured. Protein content was significantly reduced with experimental Non Feed, and carbohydrate content with Non Feed, Selenastrum, Chlorella , and Cyanophyta diets compared to the control in the lagoon. Lipid contents in body fluids were similar among the different diet groups, with the exception of the Chlorella diet, which showed a higher value. In all diets, the inorganic elements, magnesium and chloride, presented a non-significant variation profile. The concentration of sodium and potassium was significantly affected in Selenastrum and Chlorella diets, observing in the Non Feed diet a minimum value for potassium. The non-significant variation of osmolality suggests the presence of a specific osmotic regulatory mechanism independent of the diet. A particular regulation mechanism seems to exist for both calcium and manganese ion inducing similar profiles for all experimental diets with higher contents in Selenastrum and Cyanophyta diets, respectively. The higher calcium ion concentration appears associated with lower protein-carbohydrate contents, probably due to weak calcium aggregation and deposition mechanism, except for the control and Mixture diets. In general, the concentrations of organic and inorganic compounds in the body fluids of Mixture-fed A. cygnea , were more similar to those found in the control diet group. This suggests that an equal mixture of the three algae, Selenastrum, Chlorella , and Cyanophyta, is more appropriate diet to provide the necessary nutrients for a normal maintenance of A. cygnea in the wild. 相似文献
92.
de Souza HJ Amorim FV Corgozinho KB Tavares RR 《Journal of Feline Medicine and Surgery》2005,7(2):129-133
Management of a traumatic oronasal fistula with a prosthetic device in an 8-year-old male neutered domestic shorthair cat is described. The animal had fallen from a height of three stories at the age of 1 year. The fall had resulted in a fracture of the hard palate and a split in the palatal mucosa. Two surgical attempts to close the defect had been unsuccessful and an autopolymerizable acrylic resin prosthesis had produced unsatisfactory results. The management of the chronic traumatic fistula with a conical prosthetic device was fast, easy and efficient. The device was removed and a second one was put in place after 2 years. This method would appear particularly useful for obturation of large palatal defects that have failed to heal after attempts at surgical closure and is an alternative treatment for debilitated cats which may not be candidates for longer surgical procedures. 相似文献
93.
The aspartate aminotransferase family in conifers: biochemical analysis of a prokaryotic-type enzyme from maritime pine 总被引:1,自引:0,他引:1
Plant aspartate aminotransferase (AAT, EC 2.6.1.1) plays a key role in primary nitrogen assimilation, the transfer of reducing equivalents and the interchanges of carbon and nitrogen pools between subcellular compartments. We investigated the AAT family in conifers using maritime pine as the experimental model. Genes for cytosolic, mitochondrial and two plastidic isoenzymes (eukaryotic- and prokaryotic-types) were identified and their deduced amino acid sequences compared. The primary structure of the eukaryotic-type enzymes is quite well conserved, whereas the prokaryotic-type AAT is highly divergent (15% of identity). These molecular data were confirmed by the absence of immunological cross-reactivity between the two types of native AATs. The mature prokaryotic-type polypeptide was overexpressed in Escherichia coli, and the native enzyme was purified to apparent homogeneity and its molecular properties determined. The fully active recombinant holoenzyme showed highest catalytic activity at 50-60 degrees C and was moderately thermostable, retaining about 50% of its activity after incubation at 70 degrees C for 5-10 min. The presence of pyridoxal 5'-phosphate significantly increased the thermostability of the enzyme. These molecular characteristics were exploited to develop a rapid protocol for the purification of this prokaryotic-type enzyme from pine cotyledons. The results will be useful for studying aspartate and amino acid metabolism in trees. 相似文献
94.
Jennifer S. Taintor DVM Terri HathcockMarta Barba DVM Fernanda Cesar Heather Gossett 《Journal of Equine Veterinary Science》2014
This pilot study was performed to determine the need for future investigation of the effect of transportation, environmental changes, and athletic competition on fecal shedding of Salmonella spp. in sport horses. Fecal samples were collected once daily from 20 healthy horses that were competing in National Collegiate Athletic Association equestrian event that occurred over a 3-day period. The horses were divided into four groups with five horses per group. The groups were divided based on travel distance. Fresh fecal samples were collected daily and cultured for Salmonella spp., through bacterial culture, for a minimum of 3 days for three groups that traveled to compete and for 15 days for a group that was housed at the competition location. All fecal samples were negative for Salmonella spp. Although this was a pilot study with a small sample size and limited collection days, the results of this study question the effects of the stress of transportation, new environment, and athletic activity on fecal shedding of Salmonella spp. in horses. A larger study, however, is needed to further investigate these findings. 相似文献
95.
Mary Alexandra da Costa Fernanda Pinto‐Ferreira Roblia Pond Amorim de Almeida Felippe Danyel Cardoso Martins Adriene Lino Pires Marcelle Mareze Regina Mitsuka‐Bregan Roberta Lemos Freire Rosalynd Vinicios da Rocha Moreira Juliene Meira Borges Italmar Teodorico Navarro 《Zoonoses and public health》2020,67(2):122-129
96.
Vanessa de Freitas Ferreira Fernanda Carolina Ribeiro Dias Kyvia Lugate Cardoso Costa Sérgio Luis Pinto da Matta Fabiano Rodrigues de Melo Fabiana Cristina Silveira Alves de Melo 《Anatomia, histologia, embryologia》2021,50(2):379-386
Philander frenatus is an important marsupial for the maintenance and conservation of the Atlantic Rainforest, however, it has biological characteristics that are still little explored. The study of the reproductive biology is an important key to understand the species reproductive strategies and to improve the development of conservation and management activities. The present study aimed to conduct a histological and morphometric investigation of the testis structure and function of P. frenatus. The average body and testicular weight were 445 g and 0.74 g, respectively, with a gonadosomatic index of 0.17%. The seminiferous tubules occupying 64.95% of the organ, totalising 9.26 m per gram of testis. The tubulesomatic and epitheliumsomatic indexes were 0.10% and 0.07%, respectively. Philander frenatus showed cell loss of approximately 98% during the proliferative phase and the spermatogenic yield was 10.3 cells. The high loss during the mitotic phase contributed to the low spermatogenic yield. The testicular parenchyma was composed of 35% of intertubular components, one of the highest proportions observed in mammals. Leydig cells were responsible for approximately 25% of the testes, followed by lymphatic space (6.44%), blood vessels and connective tissue (4% together). The organisation of the intertubular components resembles the Fawcett III category. The volume and number of Leydig cell per gram of testis were 2,627.12 µm3 and 91.28 × 106 cells, respectively. High investment in the intertubular compartment, specifically number and volume of Leydig cells in P. frenatus is consistent with territorial behaviour and polygynic mating system, which have greater androgenic capacity. 相似文献
97.
Fernanda Gabriela Fumuso Mariana Lucía Bertuzzi Nicolás Velásquez González Marcelo H. Miragaya Maria Ignacia Carretero 《Reproduction in domestic animals》2021,56(7):958-964
Semen cryopreservation is not available for massive use in South American Camelids (SACs) due to the lack of an efficient protocol and the low pregnancy rates obtained with artificial insemination (AI). The use of a single cryoprotectant (CP) is commonly used in SACs frozen semen. The objective of the study was to evaluate the combined cryoprotective capacity of two permeable CPs at different stages of the cryopreservation protocol in llama semen. Sixteen ejaculates from 4 llama males were analysed, and sperm quality was assayed in raw semen, at 5°C, after equilibration of samples with the CPs and when samples were thawed. The following CPs and combination were used: 6% glycerol (GL), 6% dimethylformamide (DMF) and the combination of both CPs: 3% GL and 3% DMF. A Kruskal–Wallis test and an experimental factorial design, considering one factor with four levels (raw semen, 6% GL, 6% DMF and GL/DMF), were used. Total sperm motility and live sperm with intact acrosomes remained unchanged after equilibration of samples (p > .05). A significant decrease in the percentage of functional membrane, motile and live sperm with intact acrosomes was observed when samples were thawed (GL, DMF and GL/DMF). Nevertheless, the cryopreservation protocols used preserved sperm DNA quality; thus, sperm chromatin condensation and DNA fragmentation were unaffected (p > .05) when GL, DMF and GL/DMF were used. To conclude, no superiority was found between the use of a single or a combination of permeable cryoprotectants to freeze llama semen. 相似文献
98.
Pereira FM Rosa E Fahey JW Stephenson KK Carvalho R Aires A 《Journal of agricultural and food chemistry》2002,50(21):6239-6244
Broccoli inflorescences have been recognized as components of healthy diets on the basis of their high content of fiber, vitamin C, carotenoids, and glucosinolates/isothiocyanates. Broccoli sprouts have been recently shown to have high levels of glucoraphanin (4-methylsulfinylbutyl glucosinolate), the precursor of the chemoprotective isothiocyanate, sulforaphane. This study evaluated the effects of temperature and developmental stage on the glucosinolate content of broccoli sprouts. Seedlings cultivated using a 30/15 degrees C (day/night) temperature regime had significantly higher glucosinolate levels (measured at six consecutive days postemergence) than did sprouts cultivated at lower temperatures (22/15 and 18/12 degrees C; p < 0.001). Both higher (33.1 degrees C) and lower (11.3 degrees C) constant temperatures induced higher glucosinolate levels in sprouts grown to a uniform size. Glucosinolate levels were highest in cotyledons and lowest in roots of sprouts dissected both early and late in the 11 day developmental span investigated. Nongerminated seeds have the highest glucosinolate levels and concordantly greater induction of mammalian phase 2 detoxication enzymes. Levels decline as sprouts germinate and develop, with consistently higher glucosinolate content in younger developmental stages, independent of the temperature regime. Temperature stress or its associated developmental anomalies induce higher glucosinolate levels, specific elevations in glucoraphanin content, and parallel induction of phase 2 chemoprotective enzymes. 相似文献
99.
100.
Radan Elvis Matias de Oliveira Giovanna Almeida Santoro Augusto Carlos da Bôaviagem Freire Fernanda Löffler Niemeyer Attademo Stella Almeida Lima Aline da Costa Bomfim Ana Bernadete Lima Fragoso Flávio José de Lima Silva Simone Almeida Gavilan Moacir Franco de Oliveira 《Anatomia, histologia, embryologia》2020,49(1):25-30
The aortic arrangement is an important structure associated with the maintenance of homeostasis. Based on this information, this study was conducted to describe the collateral arteries of the aortic arch of Antillean manatee and define the standard model for the species. Three specimens, an adult male, adult female and a male neonate, all strandings on the coast of the state of Rio Grande do Norte, Brazil, were used. The study was performed in the Laboratory of Morphophysiology of Vertebrates of the Federal University of Rio Grande do Norte, where in situ photographs were taken to demonstrate their topography. Subsequently, their hearts were removed and fixed in 10% formaldehyde and after 72 hr were dissected and analysed, obtaining schematic drawings and photographs of the vascular arrangement. The aortic arch was represented by three collateral arteries identified as the brachiocephalic trunk, left common carotid artery and left subclavian artery. This arrangement was similar to that found for other sirenians, and yet, for other mammals like hooded seal, murine, margarita island capuchin, black-handed tamarin, Mongolian gerbil and human. The morphological similarity presented in this study with different species of mammals, including humans, may contribute valuable information from an evolutionary point of view. 相似文献