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41.
Histopathological and behaviour effects of formaldehyde treatment in juvenile mullet,Mugil liza (Valenciennes) 下载免费PDF全文
Eduardo Pahor‐Filho Kleber Campos Miranda Filho Marta Klosterhoff Luis Alberto Romano Joaber Pereira Júnior 《Aquaculture Research》2015,46(12):3040-3045
Considerable losses may be related to diseases caused by parasites in aquaculture. Formaldehyde (37% gas dissolved in water) is an effective chemotherapeutic, widely used to control ectoparasites in fish. However, for many species of fish used in aquaculture, the control of external parasites and the deleterious effects of formaldehyde in short‐term baths are still uncertain. In order to clarify some gaps, 1 h‐prophylactic baths (67.5, 135, 270, 405 and 540 mg L?1 formaldehyde in triplicate) were performed in juvenile mullet, Mugil liza (Valenciennes). Results showed that prophylactic baths of 135 mg L?1 formaldehyde by 1 h did not cause death in tested mullets. At this concentration, histopathologies were mild and fish survival was high. However, fish exposed to increasing concentrations of formaldehyde presented severe histopathologies in the gills besides behavioural and morphological alterations. The histopathological and behavioural implications of formaldehyde use in aquaculture are discussed. 相似文献
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Vikas Kumar Harinder P. S. Makkar Nicholas Romano Klaus Becker 《Journal Of Applied Aquaculture》2019,31(1):48-67
Detoxified Jatropha kernel meal (DJKM) was created through heat and solvent extraction and replaced fish meal (FM) at 0% (Control), 50% (J50), or 62.5% (J62.5) in common carp Cyprinus carpio fingerling (initial mean weight ± SD; 22 ± 0.12 g) diets over 16 weeks. Growth performance and feeding efficiencies were similar (P > 0.05) among groups, but nutrient digestibilities and digestive enzyme activities were significantly higher (P < 0.05) in Control than others. The slightly lower growth and significantly lower nutrient digestibility in carp fed DJKM indicates a need to improve the nutritive value of DJKM as a promising and sustainable FM alternative. 相似文献
44.
Delgado F Etchechoury D Gioffré A Paolicchi F Blanco Viera F Mundo S Romano MI 《Veterinary microbiology》2009,134(3-4):383-387
Paratuberculosis or Johne's disease is a chronic infectious disorder caused by Mycobacterium avium subsp. paratuberculosis (Map). The disease produces diarrhea and weight loss in cattle and other animal species, and it is characterized by granulomatous enteritis and lymphadenitis. Histopathology and in situ techniques can be used as a diagnostic test, but the performance of these methods was not previously compared. The aim of this paper was to evaluate the ability of immunohistochemistry and in situ hybridization to detect Map in formalin-fixed tissue samples from infected cattle. Samples (ileum or ileocecal lymph node) from four animals that had positive Map culturing, lesions and detectable acid fast bacilli, as well as from two control animals, were tested by immunohistochemistry and in situ hybridization. Immunostaining and positive hybridization were observed in areas with lesions from infected animal samples, inside the cytoplasm of macrophages, epithelioid and giant cells. Immunostaining was intense in three samples and weak in one, while hybridization was weak in all cases. In situ hybridization was positive in negative areas of tissues analyzed by immunohistochemistry, which could be related to spheroplast detection as it was previously described for this method. Control samples resulted negative by these two methods. Both techniques were able to detect Map in formalin fixed and paraffin embedded tissues, however immunohistochemistry produced higher intensity staining and was easier to perform. Therefore, we believe that immunohistochemistry and in situ hybridization to be useful for the post-mortem diagnosis and research of Paratuberculosis. 相似文献
45.
A 7-y-old, intact male Alaskan Malamute was presented with a 3-mo history of stertor and epistaxis. Computed tomography of the skull revealed generalized loss of gas throughout both nasal passages with replacement by a soft tissue mass that traversed the cribriform plate. Histopathology revealed neoplastic neuroblast cells arranged in anastomosing cords, as well as separately located aggregates of ganglion cells. Both neoplastic cell populations demonstrated immunoreactivity to MAP-2, TuJ-1, and synaptophysin. Neuroblastic cells additionally exhibited punctate immunoreactivity to MCK and CK8/18. We document here both the positive neural immunohistochemical markers for this neoplasm, as well as propose possible histomorphologic variants. 相似文献
46.
SUMMARY: Selection indices were developed for combining marker information and animal model PTA for offspring, grandoffspring, and great-grandoffspring of sires. The sires had marker-QTL linkages identified in granddaughter designs (GDD). Effects of size and s. e. of marker effects and of weight given to own and progeny records in PTA on gain in accuracy of selection due to a marker were quantified. Gains were negligible for high weight or large s. e., even if the marker effect was substantial. Gains were compared among offspring (O), grandoffspring (GO), and great-grandoffspring (GGO), when the marker effect in the sire was the only marker information. Gains decreased strongly for GO and were smallest for GGO. Assuming that progeny test (PT) daughters of some sons of the sire were also marker genotyped, the selection index was mo dified to incorporate this marker information on sons in addition to that on the sire from the GDD for selection of GO. For the current size of the PT, gain from including marker data on PT daughters was negligible, requiring 200 to 1000 PT daughters. Polymorphism Information Content (PIC) was computed as the fraction of O, GO, and GGO with marker allelic inheritance traceable to the sire. PIC in GO exceeded .8 and approached PIC in O only if a marker had at least 10 alleles at equal frequencies. ZUSAMMENFASSUNG: Verwendung von genetischen Markern bei Enkelin-Selektionspl?nen Selektionsindices wurden hergeleitet, um Information von Markergenorten zu kombinieren mit Tiermodell-Zuchtwerten für Nachkommen der ersten, zweiten und dritten Generation von Vatertieren. Die Vatertiere hatten Marker-QTL Kopplungsbeziehungen, die in "granddaughter designs (GDD)" nachgewiesen worden waren. Die Einflüsse von Gr??e und Standardfehlern der Markereffekte und der Gewichtung von Eigen- und Nachkommenleistungen im Tiermodell-Zuchtwert auf die Verbesserung der Selektionsgenauigkeit durch die Markerinformation wurden ermittelt. Verbesserungen waren gering für hohe Gewichtung oder gro?e Standardfehler. Verbesserungen wurden verglichen für Nachkommen der ersten, zweiten und dritten Generation, wenn die Markerinformation nur aus dem GDD stammte. Verbesserungen waren stark reduziert bzw. sehr gering für Nachkommen der zweiten bzw. dritten Generation. Der Selektionsindex wurde modifiziert, um begrenzte Markerinformation von T?chtern aus der Nachkommenprüfung von S?hnen eines Vatertieres miteinzubeziehen. Diese Information war nur hilfreich, wenn mindestens 200 bis 1000 T?chter getestet waren. Der Polymorphismus-Informationsgehalt (PIC) wurde berechnet als der Anteil von Nachkommen der ersten, zweiten und dritten Generation, für den die Vererbung eines Markeralleles zum Vatertier zurückverfolgt werden konnte. Zumindest 10 Allele mit gleichen Frequenzen waren notwendig, um ein PIC von .8 und ein PIC in Nachkommen der zweiten Generation von ?hnlich hohen Wert wie für Nachkommen der ersten Generation zu erhalten. 相似文献
47.
Alexandre Lima NEPOMUCENO Renata FUGANTI-PAGLIARINI Maria Sueli Soares FELIPE Hugo Bruno Correa MOLINARI Edivaldo Domingues VELINI Eduardo Romano de Campos PINTO Maria Lucia Zaidan DAGLI Galdino ANDRADE FILHO Patr cia Machado Bueno FERNANDES 《农业科学与工程前沿(英文版)》2020,7(2):204-210
Globally, the area of land cultivated with genetically modified (GM) crops has increased a thousand-fold over the last two decades. Although this technology has become important for food production, the regulatory frameworks that underpin these outcomes are based on a list of requirements for a risk assessment that differ from country to country. In recent years, policymakers have had the opportunity to learn from the controversies over transgenics to create effective regulatory milestones for emerging technologies, allowing them to reach their potential for a more sustainable agriculture, ensuring food security. In Brazil, Law No. 11.105 of 24 March 2005 established a framework with four main organizations responsible for risk assessment and management. However, most of new breeding technologies did not exist at that time and were not considered in this law. In 2016, Normative Resolution No. 16 of the National Biosafety Technical Commission (CTNBio) was established to address this gap based on the evaluation of the products obtained through these techniques (termed Innovative Precision Improvement Techniques in the resolution), in a case-by-case consultation system. Briefly, if the product is designated to be a GM, the developer will have to go through the biosafety requirements and will be approved only after CTNBio risk assessment. If the product is designated not to be GM (for the purposes of the legislation), then it can be registered using the existing procedures. Currently, 152 GM products are commercially approved in Brazil. In 2018, CTNBio assessed the first consultation on commercial release of plants generated using the new breeding technologies and has subsequently approved six products. It is expected that many institutions would be able to participate in Brazilian and world markets, developing and introducing new biotechnological solutions and products through a more sustainable approach and without facing public disapproval, a common issue for GM crops. 相似文献
48.
Grecica Mariana Colombo Cleber dos Santos Simio Marcos Josu Schmitz Virgínia Fonseca Pedrosa Luis Alberto Romano Marcelo Borges Tesser Patrícia Baptista Ramos Wilson Wasielesky Jos María Monserrat 《Aquaculture Research》2020,51(4):1551-1566
This study investigated the effects of the use of the inclusion of açaí on the diet of shrimp Litopenaeus vannamei on antioxidant and histopathological responses after exposure to ammonia. The shrimps were fed two experimental diets: control and with 10% of açaí inclusion (W/W), for 35 days. Afterwards, the organisms were exposed at four concentrations of ammonia (0.01‐control; 0.26; 0.48 and 0.91 mg NH3‐N L?1) for 96 hr. The total antioxidant capacity (ACAP) of the gills decreased significantly in both diets when exposed to ammonia, whereas in the muscle, the açaí promoted an increase in ACAP. Concomitantly, lipid peroxidation levels increased in the gills and decreased in muscle. After exposure to ammonia, glutathione‐S‐transferase activity increased in hepatopancreas in shrimps fed with açaí facilitating the detoxification of lipid peroxidation by‐products, and the concentration of protein sulfhydryl groups decreased in the gills and muscle of the shrimp of the control diet, evidencing protein damage, an unobserved response in shrimps that received the açaí diet. Histopathological changes decreased in açaí‐fed shrimps about the control diet after exposure to ammonia. It is concluded that açaí mitigated ammonia‐induced histopathological changes, improved the antioxidant defence system (gills and muscle) and attenuated the lipid damage in the muscle. 相似文献
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50.
Romano Dallai Vittoria Cavallo Luigi Federico Falso Pietro Paolo Fanciulli 《Pedobiologia》2000,44(3-4)
The fine structure of the male reproductive system of Allacma fusca (L.) is described. The system consists of testes, deferent ducts, seminal vesicles, ejaculatory duct and accessory glands. The nature of each part is established. Secretions from the seminal vesicles are stored in the lumen of these organs, then flow into the ejaculatory duct and are used to produce spermatophores. The epithelium of this tract has secretory activity and osmoregulatory function. Secretions and spermatozoa are stored into two distinct parts of the ejaculatory duct, divided by a transverse cuticular septum. 相似文献