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101.
Mezo M González-Warleta M Castro-Hermida JA Ubeira FM 《Veterinary parasitology》2008,157(3-4):235-243
Fasciola hepatica infection is an important cause of lost productivity in livestock worldwide. Effective control of fasciolosis is difficult, especially in milking cows, which can only be treated during dry periods, a control strategy that has not been yet evaluated. In this cross-sectional study, we investigated the effect of the type of flukicide treatment on the prevalence and intensity of infection in dairy cattle from Galicia, an area where fasciolosis is endemic and which is also the main milk-producing region in Spain. Faecal samples were taken from 5188 dairy cows on 275 randomly selected farms for measurement of the concentration of F. hepatica coproantigens by a monoclonal antibody based immunoassay (MM3-COPRO ELISA). On the same day as the sampling, each farm owner/manager was questioned about the types of treatment used on the farm. Three groups of farms were considered according to the fasciolicide treatment: (A) flukicides were not used, (B) an anthelmintic effective against mature stages of flukes was used (albendazole or netobimin) and (C) a fasciolicide effective against immature and mature stages was used (triclabendazole: TCBZ). Results indicated that 16.0% (832/5188) cows from 61.1% (168/275) herds were infected by F. hepatica. The mean coproantigen concentration in infected herds was 13.0ng/ml (range 0.9-112.6ng/ml). The highest individual concentration recorded was 496.6ng/ml. Herd and within-herd prevalences of F. hepatica were similar in all three groups, but surprisingly, individual prevalence and antigen concentration were higher in Group C (p<0.05). The percentage of farms with within-herd prevalences >25% was very high in all three groups, and no significant differences were observed. In contrast, the percentage of herds with mean antigen concentrations >20ng/ml was significantly lower (p<0.05) in Groups A and B (14.4% and 14.9%, respectively) than in Group C (50.0%). The proportion of herds that exceeded both limits (25% for prevalence and/or 20ng/ml for coproantigen concentration) was also significantly higher (p<0.05) in Group C than in untreated animals (Group A). The survey showed that most dairy farmers are unaware of the existence of F. hepatica infection on their farms, and treatments, when given, are administered without prior diagnosis. Treatment with TCBZ administered only at drying off did not show advantages over other measures including no treatment, or treatment with other benzimidazoles. Consequently, TCBZ should only be used to treat individual animals after correct diagnosis of the infection, and correct management measures taken to control re-infection. 相似文献
102.
Yabsley MJ McKibben J Macpherson CN Cattan PF Cherry NA Hegarty BC Breitschwerdt EB O'Connor T Chandrashekar R Paterson T Perea ML Ball G Friesen S Goedde J Henderson B Sylvester W 《Veterinary parasitology》2008,151(2-4):279-285
To identify the tick-borne pathogens in dogs from Grenada, we conducted a serologic survey for Ehrlichia canis in 2004 (104 dogs) and a comprehensive serologic and molecular survey for a variety of tick-borne pathogens in 2006 (73 dogs). In 2004 and 2006, 44 and 32 dogs (42.3% and 43.8%) were seropositive for E. canis, respectively. In 2006, several tick-borne pathogens were identified by serology and PCR. DNA of E. canis, Anaplasma platys, Babesia canis vogeli, Hepatozoon canis, and Bartonella sp. were identified in 18 (24.7%), 14 (19.2%), 5 (7%), 5 (7%), and 1 (1.4%) dogs, respectively. Six (8.2%) dogs were seropositive for Bartonella vinsonii subsp. berkhoffii. All dogs were seronegative and PCR-negative for Rickettsia spp. Coinfection with two or three pathogens was observed in eight dogs. Partial 16S rRNA E. canis and A. platys sequences were identical to sequences in GenBank. Partial 18S rRNA gene sequences from the Grenadian H. canis were identical to each other and had one possible mismatch (ambiguous base) from H. canis detected from Spain and Brazil. Grenadian B. c. vogeli sequences were identical to B. c. vogeli from Brazil and Japan. All of the detected pathogens are transmitted, or suspected to be transmitted, by Rhipicephalus sanguineus. Results of this study indicate that dogs from Grenada are infected with multiple tick-borne pathogens; therefore, tick-borne diseases should be included as differentials for dogs exhibiting thrombocytopenia, leukopenia, fever, or lethargy. One pathogen, E. canis, is also of potential public health significance. 相似文献
103.
Woclawek-Potocka I Piskula MK Bah M Siemieniuch MJ Korzekwa A Brzezicka E Skarzynski DJ 《The Journal of reproduction and development》2008,54(5):358-363
The present study compared the changes in isoflavones (daidzein and genistein) and their metabolite (equol and para-ethyl-phenol) concentrations in the blood plasma of cyclic and pregnant heifers after feeding with soy bean. Twelve healthy heifers were divided into three groups: cyclic heifers (days 8-12 of the estrous cycle; control group; n=4), an early pregnancy group (2 months pregnant; n=4) and a late pregnancy group (8 months pregnant; n=4). All heifers were fed a single dose of 2.5 kg of soy bean and then blood samples were taken from the jugular vein for 8 h at predetermined intervals. The concentrations of soy bean-derived isoflavones and their active metabolites were measured in the blood plasma on an HPLC system. In the blood plasma of the early- and late-pregnant heifers, we found lower concentrations and time-dependent decreases in daidzein and genistein in comparison to cyclic heifers (P<0.05). Moreover, we noticed significant increases of equol and para-ethyl-phenol in the blood plasma of the early-pregnant heifers (P<0.05). In contrast, in the blood plasma of the late-pregnant heifers, we did not find an increase in the isoflavone metabolite concentrations compared with the early-pregnant heifers (P>0.05). In conclusion, physiological status (cyclicity or pregnancy) of the females influenced the concentrations of isoflavone metabolites in the blood plasma of the heifers. The stage of pregnancy affects isoflavone absorption, biotransformation and metabolism differently and results in higher concentrations of active metabolites of isoflavones during early pregnancy in comparison to their lower concentrations during late pregnancy. Therefore, we surmise that cows are more sensitive to active isoflavone metabolite actions during early pregnancy than cyclic heifers and heifers in late pregnancy. 相似文献
104.
105.
106.
Amalia Agut Marta Soler Francisco G Laredo Francisco J Pallares Juan I Seva 《Veterinary radiology & ultrasound》2008,49(1):65-67
Solitary renal cysts are benign and in the majority of instances asymptomatic and do not require treatment. Nevertheless, treatment may be required if abdominal discomfort or pain, hypertension, infection or renal outflow obstruction occur. Under these circumstances, percutaneous management of the cyst is the easiest and fastest procedure, and no major complications are generally encountered. In this report we describe a patient with a solitary renal cyst treated successfully by a single injection of ethanol into the cyst. The sonographic appearance of the cyst changed from a well-defined hypoechoic structure to an ill-defined hyperechoic region. Canine renal cysts may be successfully managed in some instances by a single ethanol injection. 相似文献
107.
Cardoso Daniel Barros Véras Robson Magno Liberal de Carvalho Francisco Fernando Ramos Magalhães André Luiz Rodrigues de Vasconcelos Gustavo Araújo Maciel Maria Inês Sucupira Madruga Marta Suely Urbano Stela Antas de Lima Silva Janaina 《Tropical animal health and production》2019,51(6):1515-1521
Tropical Animal Health and Production - The objective of this study was to evaluate the effect of the replacement of corn by cassava dregs (0, 33, 66, and 100%) in the diet of lamb on... 相似文献
108.
Miguelangel Moncayo‐Donoso Johana M. Guevara Kalenia Mrquez-Flrez Marta R. Fontanilla Luis A. Barrera Diego A. Garzn‐Alvarado 《Anatomia, histologia, embryologia》2019,48(2):117-124
In mammals, long bones are formed by ossification of a cartilaginous mould during early stages of development, through the formation of structures called the primary ossification centre, the secondary ossification centres (SOCs) and the physeal cartilages (PCs). The PC is responsible for long bone growth. The morphology of the PC and the SOCs varies during different stages of femoral growth. In this respect, several details involving the process of murine femoral development are lacking. In the present study, a morphological characterization of femur development from the embryonic period to adulthood in mice was studied using micro‐computed tomography (micro‐CT). To achieve this aim, femora were collected at embryonic day (E) 14.5, E16.5 and E18.5 and at postnatal day (P)1, P7, P14, P35, P46 and P52. CT images were obtained using a micro‐CT scanner (X‐SkyScan 1172; Micro Photonics) and analysed using the micro‐CT 3D visualization software Mimics (Materialise NV, Leuven, Belgium) and NRecon (Micro Photonics). The results of the present study revealed that the femur and its PCs and SOCs undergo morphological changes during different stages of development, including changes in their shape as well as position and thickness. These changes may be due to the response of the femur to mechanical loads imposed by muscle surrounding the bone during these stages of development. The result of the present study is important to improve our knowledge related to ossification and growth patterns of mouse femur during development. 相似文献
109.
Marta Tikhomirov Baej Po
niak Andrzej Smutkiewicz Marcin
witaa 《Journal of veterinary pharmacology and therapeutics》2019,42(1):116-120
The pharmacokinetics of florfenicol (FF) and thiamphenicol (TP) after single intravenous (IV) and oral (PO) administration was investigated in Mulard ducks. Both antibiotics were administered at a dose of 30 mg/kg body weight, and their concentrations in plasma samples were assayed using high‐performance liquid chromatography with ultraviolet detection. Pharmacokinetic parameters were calculated using a noncompartmental method. After IV administration, significant differences were found for the mean residence time (2.25 ± 0.21 hr vs. 2.83 ± 0.50 hr for FF and TP, respectively) and the general half‐life (1.56 ± 0.15 hr vs. 1.96 ± 0.35 hr for FF and TP, respectively) indicating slightly slower elimination of TP as compared to FF. The clearance, however, was comparable (0.30 ± 0.07 L/hr/kg for FF and 0.26 ± 0.04 L/hr/kg for TP). The mean volume of distribution was below 0.7 L/kg for both drugs. Pharmacokinetics after PO administration was very similar for FF and TP suggesting minor clinical importance of the differences found in the IV study. Both antimicrobials showed rapid absorption and bioavailability of more than 70% indicating that PO route should be an efficient method of FF and TP administration to ducks under field conditions. 相似文献
110.