9 research outputs found
UPPER AIRWAY EVALUATIONS OF THOROUGHBRED RACEHORSES IN A PRIVATE CLINIC IN CURITIBA, BRAZIL – RESTING ENDOSCOPIC FINDINGS IN 587 HORSES
Obstructive upper airway diseases are an important cause of poor performance in athletic horses. The present study aimed to determine the prevalence of common URT abnormalities (pharyngeal lymphoid hyperplasia - PLH, dorsal displacement of the soft palate - DDSP and recurrent laryngeal neuropathy - RLN) in a population of Thoroughbred racehorses in training submitted to resting endoscopy in a private clinic in Curitiba, Paraná, Brazil. 587 URT resting endoscopies, 385 2-year-old and 202 3-year-old-plus horses, were performed during the period of the study and the clinical records of all the examinations were reviewed and analysed. 340 (57.9 %) horses were evaluated for routine athletic follow up, 15 (2.6%) were pre-purchase examinations, 83 (14.1%) were examined as an investigation for cough, 58 (9.9%) horses had poor performance, 48 (8.2%) had abnormal respiratory noise, 35 (6.0%) had epistaxis and 8 (1.4%) had nasal discharge. Pharyngitis (Grades III, IV PLH) was diagnosed in 198 (33.7%) horses and was more prevalent in the 2-year-old group than in the older horses (40.5% vs. 20.8%, P<0.05). DDSP was identified in 185 (31.5%) horses, Grade III RLN in 13 (2.2%) and Grade IV was seen in 21 (3.6%) horses. The present study gives a prevalence of upper airway abnormalities in resting endoscopic evaluation in a racehorse population in Brazil
Pyrethroid toxicity in silver catfish, Rhamdia quelen Toxicidade dos piretróides sobre Jundiás, Rhamdia quelen
This study aimed to determine both the lethal and sublethal concentrations of Cypermethrin in young Silver Catfish (Brazilian "Jundiá", Rhamdia quelen) on aquatic environment during 96 hours, as well as to determine the Cypermethrin and Deltamethrin sublethal concentrations during the initial embryonic development period of Rhamdia quelen, and to verify their respective rates of fertilization, hatching and survival. Pyrethroid nowadays is a widely used insecticide, which presents a high toxicity to fish. In order to determine lethal and sublethal concentrations, 120 silver catfish were used; each one had an average weight of 59.58±4.50g and an average size of 20.33±2.34cm. Concentrations used were 0, 1.0, 1.5, 2.0, 2.5, 3.0, 5.0, 10.0, 15.0 and 20.0mg of Cypermethrin per liter of water (mg/L). Fish were exposed to the product in 30-liter fish tanks. In each fish tank there were four fishes and the product was applied three times, i.e., a total of twelve fish were exposed to the product at each application, and a total of 120 fish during the entire experiment (n=120). In order to determine the Cypermethrin and Deltamethrin sublethal concentrations during the initial embryonic development, ovulation induction was performed on female fishes using hormones, and then and egg collection was performed. The eggs were then hydrated and fertilized in Cypermethrin and Deltamethrin in different concentrations: 0.001, 0.01, 0.1, 1.0 and 10.0mg/L of Cypermethrin and 0.001, 0.01, 0.1, 0.5 and 1.0mg/L of Deltamethrin, in addition to the control group (0mg/L). After fertilization, the eggs were kept in containers with the respective pesticides of Cypermethrin and Deltamethrin until hatching, when hatching rate was verified. Then the alevins, from the hatching, were kept on their respective concentrations of Cypermethrin and Deltamethrin so that the survival rate could be analyzed regarding the tested insecticides, during both 12-hour and 24-hour periods. Concerning the sublethal and lethal concentrations, Silver Catfish was sensitive to the tested concentrations of Cypermethrin, showing symptoms of poisoning, such as loss of balance, swimming alteration, dyspnea (they kept their mouths and opercula open), upright swimming and sudden spiral swimming movements. The intensity of such symptoms varied in proportion to the concentration used. The concentrations above 3.0mg/L were considered lethal to the species, since every animal exposed to concentrations between 3.0 and 20.0mg/L had died, while concentrations between 1.0 and 2.5mg/L were considered sublethal. Lethal concentration of Cypermethrin to Silver catfish, in 96 hours, was 1.71 milligram per liter of water. Concerning the sublethal concentration of Cypermethrin and Deltamethrin during the initial embryonic development, the results show that both pyrethroids had significantly decreased the analyzed parameters when comparing them with the control group. It was concluded that, even with the fish being more resistant to pyrethroids in comparison with other species, both the young animals and the ones in stage of embryonic development were susceptible to the effects of these pesticides.<br>O presente estudo teve o objetivo de determinar a concentração letal e subletal da cipermetrina por via hídrica em 96 horas em jundiás (Rhamdia quelen) jovens, determinar a concentração subletal da cipermetrina e da deltametrina durante o período inicial do desenvolvimento embrionário do Rhamdia quelen e verificar suas respectivas taxas de fertilização, eclosão e sobrevivência. Os piretróides são inseticidas amplamente utilizados atualmente e apresentam alta toxicidade para peixes. Para determinação da concentração letal e subletal foram utilizados 120 jundiás com peso médio de 59,58±4,50g e comprimento médio de 20,33±2,34cm. As concentrações utilizadas foram 0; 1,0; 1,5; 2,0; 2,5; 3,0; 5,0; 10,0; 15,0 e 20,0mg de cipermetrina por litro de água (mg/L). Os peixes foram expostos ao produto dentro de aquários com capacidade para 30 litros. Em cada aquário foram colocados quatro peixes e cada tratamento teve três repetições, totalizando doze peixes por tratamento. Para determinar a concentração subletal da cipermetrina e deltametrina na fase de desenvolvimento embrionário foi realizada a indução da ovulação em fêmeas de jundiá através de hormônios, com posterior coleta dos ovos. Os ovos foram hidratados e fertilizados em soluções de cipermetrina e deltametrina em diferentes concentrações, sendo estas: 0,001; 0,01; 0,1; 1,0 e 10,0mg/L para cipermetrina e 0,001; 0,01; 0,1; 0,5 e 1,0mg/L para deltametrina, além do grupo controle (0mg/L). Após a fertilização, os ovos permaneceram em recipientes com os respectivos pesticidas até o momento da eclosão onde foi analisada a taxa de eclosão. Em seguida as larvas, a partir da eclosão dos ovos, foram mantidas nas respectivas concentrações de cipermetrina e deltametrina para analisar a taxa de sobrevivência frente aos inseticidas testados, durante 12 e 24 horas. Em relação as concentrações letais e subletais de jundiás jovens, estes apresentaram-se sensíveis à cipermetrina nas concentrações testadas, apresentando sinais de intoxicação como perda de equilíbrio, alteração na natação, dispnéia mantendo a boca e os opérculos abertos, nados verticais e movimentos súbitos de natação em forma de espiral. A intensidade destes sinais variou proporcionalmente a concentração utilizada. As concentrações acima de 3,0mg/L foram consideradas letais para a espécie em 96 horas, pois todos os animais expostos a concentrações entre 3,0 e 20,0mg/L vieram a óbito, enquanto que as concentrações entre 1,0 e 2,5mg/L são subletais. A CL50 96 horas da cipermetrina para o jundiá foi 1,71mg/L. Em relação aos efeitos da cipermetrina e deltametrina sobre a fase de desenvolvimento embrionário, os resultados mostraram que ambos os piretróides diminuíram significativamente os parâmetros analisados em comparação com o grupo controle. Conclui-se que mesmo o jundiá mostrando ser mais resistente aos piretróides em comparação com outras espécies, tanto animais jovens como animais em fase de desenvolvimento embrionário mostraram-se sensíveis aos efeitos destes pesticidas
Pyrethroid toxicity in silver catfish, Rhamdia quelen
This study aimed to determine both the lethal and sublethal concentrations of Cypermethrin in young Silver Catfish (Brazilian "Jundiá", Rhamdia quelen) on aquatic environment during 96 hours, as well as to determine the Cypermethrin and Deltamethrin sublethal concentrations during the initial embryonic development period of Rhamdia quelen, and to verify their respective rates of fertilization, hatching and survival. Pyrethroid nowadays is a widely used insecticide, which presents a high toxicity to fish. In order to determine lethal and sublethal concentrations, 120 silver catfish were used; each one had an average weight of 59.58±4.50g and an average size of 20.33±2.34cm. Concentrations used were 0, 1.0, 1.5, 2.0, 2.5, 3.0, 5.0, 10.0, 15.0 and 20.0mg of Cypermethrin per liter of water (mg/L). Fish were exposed to the product in 30-liter fish tanks. In each fish tank there were four fishes and the product was applied three times, i.e., a total of twelve fish were exposed to the product at each application, and a total of 120 fish during the entire experiment (n=120). In order to determine the Cypermethrin and Deltamethrin sublethal concentrations during the initial embryonic development, ovulation induction was performed on female fishes using hormones, and then and egg collection was performed. The eggs were then hydrated and fertilized in Cypermethrin and Deltamethrin in different concentrations: 0.001, 0.01, 0.1, 1.0 and 10.0mg/L of Cypermethrin and 0.001, 0.01, 0.1, 0.5 and 1.0mg/L of Deltamethrin, in addition to the control group (0mg/L). After fertilization, the eggs were kept in containers with the respective pesticides of Cypermethrin and Deltamethrin until hatching, when hatching rate was verified. Then the alevins, from the hatching, were kept on their respective concentrations of Cypermethrin and Deltamethrin so that the survival rate could be analyzed regarding the tested insecticides, during both 12-hour and 24-hour periods. Concerning the sublethal and lethal concentrations, Silver Catfish was sensitive to the tested concentrations of Cypermethrin, showing symptoms of poisoning, such as loss of balance, swimming alteration, dyspnea (they kept their mouths and opercula open), upright swimming and sudden spiral swimming movements. The intensity of such symptoms varied in proportion to the concentration used. The concentrations above 3.0mg/L were considered lethal to the species, since every animal exposed to concentrations between 3.0 and 20.0mg/L had died, while concentrations between 1.0 and 2.5mg/L were considered sublethal. Lethal concentration of Cypermethrin to Silver catfish, in 96 hours, was 1.71 milligram per liter of water. Concerning the sublethal concentration of Cypermethrin and Deltamethrin during the initial embryonic development, the results show that both pyrethroids had significantly decreased the analyzed parameters when comparing them with the control group. It was concluded that, even with the fish being more resistant to pyrethroids in comparison with other species, both the young animals and the ones in stage of embryonic development were susceptible to the effects of these pesticides