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排序方式: 共有204条查询结果,搜索用时 15 毫秒
91.
92.
Roberta Garbelini Gomes Reginaldo Luís Oliveira Carlos Guilherme de Castro Schutzer Thales Ricardo Rigo Barreiros Marcelo Marcondes Seneda 《Journal of Equine Veterinary Science》2014
The objective of this study was to compare the rate of ovulation when deslorelin and/or human chorionic gonadotropin (hCG) was administered in mares in both the transition period and the ovulatory season. A total of 200 Paint Horses, Quarter Horses, and crossbred mares were used during the transition season (July to September) and the ovulatory season (October to February) of the southern hemisphere. The animals were divided into four groups. In the control group (n = 72), mares received 1 mL of saline; in deslorelin group (n = 171), 1.5 mg of deslorelin was administered by intramuscular (IM) injection; in hCG group (n = 57), 1,667 IU of hCG was administered IV; and in hCG + deslorelin group (n = 438), 1.5 mg of deslorelin (IM) and 1,667 IU of hCG (IV) were administered. The drugs were administered after follicles ≥35 mm in diameter were identified and grade III uterine edema was observed. At 48 hours after application, ultrasonography was performed to detect ovulation. During the transition period, the ovulation rates were 4.3% (control), 78.6% (deslorelin), 50% (hCG), and 73.3% (hCG + deslorelin). During ovulatory season, the ovulation rates were 16.4% (control), 68.8% (deslorelin), 60% (hCG), and 73% (hCG + deslorelin). There was no significant difference (P > .05) in the ovulation rate between the groups or the periods, except that the control group was lower than all others. Furthermore, both hCG and deslorelin are viable options for inducing ovulation during the transition period before ovulation season. 相似文献
93.
Juliana R. Peiró Geison M. Nogueira Guilherme P. Nogueira Silvia H.V. Perri Daniel Cardoso 《Canadian journal of veterinary research》2009,73(3):237-240
The main objective of this study was to evaluate a recumbent left flank approach to bilateral ovariectomy in prepubertal heifers and to develop an optimal surgical technique for this procedure. Both ovaries were removed from 6 Nelore heifers by left flank approach without any complications, except in 1 heifer, which was believed to have had only 1 ovary based on ultrasound and exploration during surgery, but was later found to have a remaining functional ovary. Ovariectomy via left flank approach in recumbent prepubertal heifers is feasible and technically easy. This procedure does not involve special instrumentation and, despite the invasive approach, it allows optimal visualization of the ovaries and uterus. 相似文献
94.
da Silva JK Sousa PJ Andrade EH Maia JG 《Journal of agricultural and food chemistry》2007,55(23):9422-9426
The leaves and fine stems, bark, and trunk wood oils of Aniba canelilla showed yields ranging from 0.2 to 1.3%. The main volatile constituent identified in the oils was 1-nitro -2-phenylethane (70.2-92.1%), as expected. The mean of DPPH radical scavenging activity (EC 50) of the oils (198.17 +/- 1.95 microg mL(-1)) was low in comparison with that of wood methanol extracts (4.41 +/- 0.12 microg mL(-1)), the value of which was equivalent to that of Trolox (4.67 +/- 0.35 microg mL(-1)), used as antioxidant standard. The mean amount of total phenolics (TP) (710.53 +/- 23.16 mg of GAE/g) and this value calculated as Trolox equivalent antioxidant capacity (TEAC) (899.50 +/- 6.50 mg of TE/g) of the wood methanol extracts confirmed the high antioxidant activity of the species. On the other hand, in the brine shrimp bioassay the values of lethal concentration (LC50) for the oils (21.61 +/- 1.21 microg mL(-1)) and 1-nitro-2-phenylethane (20.37 +/- 0.99 microg mL(-1)) were lower than that of the wood methanol extracts (91.38 +/- 7.20 microg mL(-1)), showing significant biological activities. 相似文献
95.
Guilherme Gomes Verocai Lauro Nogueira Lopes Leonardo Burlini Thaís Ribeiro Correia Clarissa Pimentel de Souza Katherina Coumendouros 《Tropical animal health and production》2009,41(7):1241-1242
This paper reports the occurrence of parasitism by the Oriental eye-fluke, Philophthalmus gralli in ostriches reared in a commercial flock from the State of Minas Gerais State, Southeastern Brazil. The two affected birds
presented lacrimation, inflammatory reaction and loss of body condition. After physical examination the birds revealed, 17
and 15 trematodes each, only in the right eyes. The economic impact of this parasite on Brazilian ostrich industry is still
undetermined, requiring further studies. 相似文献
96.
Celina Emiko OKAMOTO-OKUBO Renata Navarro CASSU Jean Guilherme Fernandes JOAQUIM Luciane dos REIS MESQUITA Sheila Canevese RAHAL Hugo S Salvador OLIVEIRA Regina TAKAHIRA Isadora ARRUDA Leandro MAIA Fernanda da CRUZ LANDIM Stelio Pacca Loureiro LUNA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(5):881
97.
Joaquim Henriques Ricardo Felisberto Bruno Almeida Joana Ramos Fernando Constantino‐Casas Jane Dobson Raquel Matos Ana Santos Rita de Sousa Margarida Alves 《Veterinary and comparative oncology》2021,19(1):183-190
Lymphoma is the most common haematological malignancy in dogs and its aetiology is largely unknown. The presence of canine vector‐borne agents (CVBD) in lymphoma tissues has been described and its causative effects questioned. We intended to evaluate the presence and extent of Leishmania infantum, Ehrlichia canis, Anaplasma phagocytophilum and Bartonella henselae infection in dogs with lymphoma. Sixty‐one dogs, living in the Lisbon metropolitan area, with a diagnosis of lymphoma were enrolled. Immunofluorescence assays were used to detect serum IgG's. The presence of DNA from CVBD agents in tumour tissue was assessed by PCR. All dogs tested negative for B. henselae, A. phagocytophilum and E. canis by both serology and PCR. Regarding L. infantum, 8.2% (n = 5) of the dogs had a positive serologic result. L. infantum DNA was detected in two samples of diffuse large B‐cell lymphoma (DLBCL). These results show an increased, but not significant, seropositivity (8.2% vs 7.9%) and molecular detection (3.3% vs 1.2%) for L. infantum in dogs with lymphoma, when compared to the reported canine population in the same geographical area. We could not identify an association between lymphoma and E. canis, A. phagocytophilum, B. henselae or Leishmania infantum infection in the studied population. Nevertheless, further studies, following dogs trough their CVBD disease evolution, are worthwhile and may help clarify a possible role of CVBD agents in lymphomagenesis. 相似文献
98.
Murakami PS Monego F Ho JL Gibson A Vilani RG Soresini GC Brockelt SR Biesdorf SM Fuverki RB Nakatani SM Riediger IN Grazziotin AL do Santos AP de Barros Filho IR Biondo AW 《Journal of zoo and wildlife medicine》2012,43(2):338-341
Mycobacterium tuberculosis complex, which includes Mycobacterium bovis, infrequently causes severe or lethal disease in captive wildlife populations. A dead coati from a wildlife triage center showing pulmonary lesions compatible with tuberculosis had raised suspicion of a potential disease caused by mycobacteria species and was further investigated. Four native coatis (Nasua nasua) with suspected mycobacterial infection were sedated, and bronchoalveolar lavages and tuberculin skin tests (TSTs) were performed. All animals tested positive upon TST. Mycobacterial culturing, Ziehl-Neelsen staining, and genetic testing were performed on postmortem samples and the etiologic agent was identified as M. bovis. Molecular genetic identification using a polymerase chain reaction panel was crucial to achieving a definitive diagnosis. 相似文献
99.
Pelegrino Marcelo Henrique Procópio Silva Sérgio Henrique Godinho de Faria Álvaro José Gomes Mancini Marcelo Teixeira Anita Fernanda dos Santos Chakraborty Somsubhra Weindorf David C. Guilherme Luiz Roberto Guimarães Curi Nilton 《Precision Agriculture》2022,23(1):18-34
Precision Agriculture - Precision agriculture provides detailed information on the spatial variability of soil properties, including nutrient content, allowing for local-specific decision making.... 相似文献
100.
Jennifer K. Balch Daniel C. Nepstad Lisa M. Curran Paulo M. Brando Osvaldo PortelaPaulo Guilherme Jonathan D. Reuning-SchererOswaldo de Carvalho Jr. 《Forest Ecology and Management》2011,261(1):68-77
Anthropogenic understory fires have affected large areas of tropical forest in recent decades, particularly during severe droughts. Yet, the mechanisms that control fire-induced mortality of tropical trees and lianas remain ambiguous due to the challenges associated with documenting mortality given variation in fire behavior and forest heterogeneity. In a seasonally dry Amazon forest, we conducted a burn experiment to quantify how increasing understory fires alter patterns of stem mortality. From 2004 to 2007, tree and liana mortality was measured in adjacent 50-ha plots that were intact (B0 - control), burned once (B1), and burned annually for 3 years (B3). After 3 years, cumulative tree and liana mortality (≥1 cm dbh) in the B1 (5.8% yr−1) and B3 (7.0% yr−1) plots significantly exceeded mortality in the control (3.2% yr−1). However, these fire-induced mortality rates are substantially lower than those reported from more humid Amazonian forests. Small stems were highly vulnerable to fire-induced death, contrasting with drought-induced mortality (measured in other studies) that increases with tree size. For example, one low-intensity burn killed >50% of stems <10 cm within a year. Independent of stem size, species-specific mortality rates varied substantially from 0% to 17% yr−1 in the control, 0% to 26% yr−1 in B1, and 1% to 23% yr−1 in B3, with several species displaying high variation in their vulnerability to fire-induced mortality. Protium guianense (Burseraceae) exhibited the highest fire-induced mortality rates in B1 and B3, which were 10- and 9-fold greater than the baseline rate. In contrast, Aspidosperma excelsum (Apocynaceae), appeared relatively unaffected by fire (0.3% to 1.0% mortality yr−1 across plots), which may be explained by fenestration that protects the inner concave trunk portions from fire. For stems ≥10 cm, both char height (approximating fire intensity) and number of successive burns were significant predictors of fire-induced mortality, whereas only the number of consecutive annual burns was a strong predictor for stems <10 cm. Three years after the initial burn, 62 ± 26 Mg ha−1 (s.e.) of live biomass, predominantly stems <30 cm, was transferred to the dead biomass pool, compared with 8 ± 3 Mg ha−1 in the control. This biomass loss from fire represents ∼30% of this forest's aboveground live biomass (192 (±3) Mg ha−1; >1 cm DBH). Although forest transition to savanna has been predicted based on future climate scenarios, our results indicate that wildfires from agricultural expansion pose a more immediate threat to the current carbon stocks in Amazonian forests. 相似文献