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The changes of cortisol, red blood cells (RBC), hemoglobin (Hb), hematocrit (Hct), heart rate (HR), respiratory rate (RR) and rectal temperature (RT) were evaluated after a reining training session in eight Quarter Horses. All parameters were measured before exercise (T0), immediately after exercise (T1), 1 h after exercise (T2), 2 h after exercise (T3) and 24 h after exercise (T4). One‐way analysis of variance (ANOVA) for repeated measures, followed Bonferroni's post hoc test, showed a significant effect of the reining training session (P < 0.0001) on cortisol, RBC, Hb, Hct, HR, RR and RT. Simple linear regression analysis showed the positive correlation (P < 0.05) between cortisol changes and variations of studied parameters in T1, T3 and T4. Exercise‐induced cortisol concentrations reflect the physiological response of reining training, suggesting that the changes observed are useful to assess the performance in reining horses and their reining training adaptability.  相似文献   
3.
Finnish isolates of Beauveria bassiana (8 isolates), Metarhizium anisopliae (7), Tolypocladium sp. (2), Paecilomyces farinosus (2), P. fumosoroseus (1), Steinernema feltiae (3) and Bacillus thuringiensis ('Muscabac') were tested for efficacy against mixed populations of Delia radicum and D. floralis under field conditions in 1986–90. All pathogens were applied preventatively, the fungi as aqueous conidial or mycelial suspensions, dry conidia or dry mycelial powder. In only two of the nine experiments did B. bassiana or M. anisopliae give some control. In 1986, B. bassiana SF85–2 and Tolypocladium sp. SF85–4 (both at rate 1.2 x 109 conidia plant‐ 1), and ‘Muscabac’ (25 g 1?1, 1 dl plant?1) reduced the number of pupae by 80%, 60% and 50%, respectively, as compared with untreated and chemical (isophenphos) controls. In 1990, M. anisopliae SF86–39 at rate 1.6 x 109conidia plant?1 and 1.5 x 108 CFU plant?1 and S. feltiae SFS‐22 (35000 plant?1), increased the yield of cauliflower 2.2, 1.8, and 2.3‐fold, respectively, as compared with the untreated control, but these yields were only 19%, 15% and 19% of those of the chemical (diazinon) control. Paecilomyces isolates were ineffective in the 1986 experiment in which they were included. Our results suggest that it is difficult to find efficient control agents among the fungal and nematode species tested for use as biopesticides against cabbage root flies, but that the potential of M. anisopliae against these pests deserves further study.  相似文献   
4.
The effect of some physical factors on the processes (hydrolysis, volatilisation) regulating the persistence of methyl bromide in fresh surface waters was investigated to complement previous research. It has been confirmed that electromagnetic radiation in the visible field has no influence on the hydrolysis kinetics of the fumigant. The removal of methyl bromide by volatilisation from stirred and ventilated solutions appears to be of greater importance in practice. It has been shown that under these conditions the half-life is directly proportional to the liquid depth. Without stirring volatilisation is greatly reduced, due to the low diffusivity of methyl bromide in the aqueous phase.  相似文献   
5.
OBJECTIVE: To determine prevalence of FeLV infection and serum antibodies against feline immunodeficiency virus (FIV) in unowned free-roaming cats. DESIGN: Cross-sectional serologic survey. ANIMALS: 733 unowned free-roaming cats in Raleigh, NC, and 1,143 unowned free-roaming cats in Gainesville, Fla. RESULTS: In Raleigh, overall prevalence of FeLV infection was 5.3%, and overall seroprevalence for FIV was 2.3%. In Gainesville, overall prevalence of FeLV infection was 3.7%, and overall seroprevalence for FIV was 4.3%. Overall, FeLV prevalence was 4.3%, and seroprevalence for FIV was 3.5%. Prevalence of FeLV infection was not significantly different between males (4.9%) and females (3.8%), although seroprevalence for FIV was significantly higher in male cats (6.3%) than in female cats (1.5%). CONCLUSIONS AND CLINICAL RELEVANCE: Prevalence of FeLV infection and seroprevalence for FIV in unowned free-roaming cats in Raleigh and Gainesville are similar to prevalence rates reported for owned cats in the United States. Male cats are at increased risk for exposure to FIV, compared with female cats.  相似文献   
6.
We have analyzed the influence of the stage of ripeness on L-phenylalanine ammonia-lyase (PAL) gene expression, accumulation of anthocyanins and total phenolics, and on antioxidant activity in the skin of table grapes treated with 20% CO2 + 20% O2 + 60 % N2 for 3 or 6 d at low temperature (0 °C). The residual effect of high CO2 treatment after transfer to air was also studied. In early harvested grapes, neither the anthocyanin content nor the accumulation of VcPAL mRNA was affected by any of the CO2 treatments applied. However, in late harvested grapes, the duration of high CO2 treatment determined its effect and a 6 d treatment with CO2 sustained higher levels of total phenolics and anthocyanin accumulation, and VcPAL expression than observed in untreated late harvested grapes. The increased antioxidant capacity was correlated with the total amount of phenolics and anthocyanins. Conversely, in grapes treated for 3 d with CO2 the phenylpropanoid pathway did not appear to be induced and a relationship between antioxidant activity and anthocyanins was not observed. Thus, further studies are needed to identify the most important antioxidants in these treated fruit.  相似文献   
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This study compared the responses shown by lactating dairy cows to four different P4-based protocols for AI at estrus. Cows with no estrous signs 96 h after progesterone intravaginal device (PRID) removal were subjected to fixed-time AI (FTAI), and their data were also included in the study. In Experiment I, follicular/luteal and endometrial dynamics were assessed every 12 h from the beginning of treatment until AI. The estrous response was examined in Experiment II, and fertility was assessed in both experiments. The protocols consisted of a PRID fitted for five days, along with the administration of different combinations of gonadotropin releasing hormone (GnRH), equine chorionic gonadotropin and a single or double dose (24 h apart) of prostaglandin F. In Experiment I (40 cows), animals receiving GnRH at the start of treatment showed a significantly higher ovulation rate during the PRID insertion period while estrus was delayed. In Experiment II (351 cows), according to the odds ratios, cows showing luteal activity at the time of treatment were less likely to show estrus than cows with no signs of luteal activity. Treatment affected the estrous response and the interval from PRID removal to estrus but did not affect conception rates 28–34 days post AI. Primiparous cows displayed a better estrous response than multiparous cows. Our findings reveal acceptable results of 5-day P4-based protocols for AI at estrus in high-producing dairy cows. Time from treatment to estrus emerged as a good guide for FTAI after a 5-day P4-based synchronization protocol.  相似文献   
9.
An outbreak of human leishmaniosis was confirmed in the southwest of the province of Madrid, Spain, between July 2009 and December 2012. Incidence of Leishmania infection in dogs was unchanged in this period, prompting a search for alternative sylvatic infection reservoirs. We evaluated exposure to Leishmania in serum samples from animals in the area with an indirect immunofluorescence test (IFAT). Using promastigotes from six culture passages and a 1/25 threshold titer, we found anti-Leishmania infantum seroreactivity in 9.3% of cats (4 of 43), 45.7% of rabbits (16/35) and 74.1% of hares (63/85). Use of promastigotes from >10 in vitro passages resulted in a notably IFAT lower titer, suggesting antigenic changes during extended culture. Postmortem inspection of seropositive animals showed no clinical signs of infection. The results clearly suggest that asymptomatic hares were the main reservoir in the outbreak, and corroborate IFAT as a sensitive serological surveillance method to detect such cryptic Leishmania infections.  相似文献   
10.
Dendroclimatological studies in a dry inner Alpine environment (750 m a.s.l.) revealed different growth response of co-occurring coniferous species to climate, which is assumed to be caused by a temporal shift in wood formation among species. The main focus of this study therefore was to monitor intra-annual dynamics of radial increment growth of mature deciduous and evergreen coniferous species (Pinus sylvestris, Larix decidua and Picea abies) during two consecutive years with contrasting climatic conditions. Radial stem growth was continuously followed by band dendrometers and modelled using Gompertz functions to determine time of maximum growth. Histological analyses of tree ring formation allowed determination of temporal dynamics of cambial activity and xylem cell development. Daily fluctuations in stem radius and radial stem increments were extracted from dendrometer traces, and correlations with environmental variables were performed. While a shift in temporal dynamics of radial growth onset and cessation was detected among co-occurring species, intra-annual radial growth peaked synchronously in late May 2011 and early June 2012. Moist atmospheric conditions, i.e. high relative air humidity, low vapour pressure deficit and low air temperature during the main growing period, favoured radial stem increment of all species. Soil water content and soil temperature were not significantly related to radial growth. Although a temporal shift in onset and cessation of wood formation was detected among species, synchronous culmination of radial growth indicates homogenous exogenous and/or endogenous control. The close coupling of radial growth to atmospheric conditions points to the importance of stem water status for intra-annual growth of drought-prone conifers.  相似文献   
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