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241.
Interaction of Beauveria bassiana and Metarhizium anisopliae with chlorpyrifos ethyl and spinosad in Spodoptera frugiperda larvae
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242.
J Duque B Macías‐García P Ruíz Tapia C Ortega Ferrusola C Zaragoza R Barrera FJ Peña 《Reproduction in domestic animals》2010,45(5):e199-e200
In this study, two unusual presentations of canine prostatitis are described; in the first case a 10‐years‐old neutered Boxer dog was presented to the Veterinary Teaching Hospital of the University of Extremadura with a complaint of anorexia, apathy and preputial discharge. In the second case, a local veterinarian referred an 8‐years‐old male Labrador to the Veterinary Teaching Hospital of the University of Extremadura. The dog had a history of pain in the caudal abdomen and preputial oedema. The final diagnosis in both cases was acute prostatitis. It is concluded that although canine prostatitis is a common disease, sometimes can have presentations that may differ from those classically described in the literature. 相似文献
243.
J.L. Alonso M.C. Simon O. Girones J.L. Muzquiz C. Ortega J. Garcia 《Research in veterinary science》1992,52(3):75-272
Fifteen ewes were inoculated subcutaneously with 2 x 10(6) cells of Corynebacterium pseudotuberculosis seven days before mating, during the embryonic stage of gestation and during the fetal stage of gestation. The clinical signs, antibody response and the consequences of the infection on reproduction were studied. None of the ewes showed any change in general condition during pregnancy. The effects of experimental infection during gestation were evident after incubation periods that ranged from 25 to 140 days after inoculation and were dependent on the time of the inoculation in relation to the period of gestation. Ewes inoculated before gestation can resolve infection. Ewes inoculated during the embryonic stage were severely affected and some aborted. In others lambs were stillborn or, if born alive, infected. Ewes inoculated during the fetal stage of gestation did not show reproductive disorders although some remained chronically infected. 相似文献
244.
Divergent selection for uterine capacity in rabbits. I. Genetic parameters and response to selection
A 10-generation divergent selection experiment for uterine capacity (UC) measured as litter size in unilaterally ovariectomized females was carried out in rabbits. A total of 2,996 observations on uterine capacity of does (up to four parities) was recorded. Laparoscopy was performed at d 12 of their second gestation, and ovulation rate (OR) and number of implanted embryos (IE) were recorded in 735 does. Prenatal survival (PS) was assessed as UC/OR, embryo survival (ES) as IE/OR, and fetal survival (FS) as UC/IE. Genetic parameters and genetic trends were inferred using Bayesian methods. Marginal posterior distributions of all unknowns were estimated by Gibbs sampling. Heritabilities of UC, OR, IE, ES, FS, and PS were 0.11, 0.32, 0.22, 0.04, 0.14, and 0.09, respectively. Genetic and phenotypic correlations between FS and ES were low, suggesting different biological mechanisms for the two periods of survival. After 10 generations of selection, the divergence was approximately 1.5 rabbits, or approximately 1% per generation. Approximately one-half of this response was obtained in the first two generations of selection, which may suggest the presence of a major gene segregating in the base population. 相似文献
245.
246.
Salvetti NR Ricci N Dallard BE Lorente JA Iguzquiza I Ortega HH 《Anatomia, histologia, embryologia》2000,29(3):129-134
Most studies on the biochemistry and structure of the corpus luteum have focused on elucidating the processes of progesterone synthesis and release. In the present work, the histochemical composition of the corpus luteum of the rat was evaluated using lectinhistochemistry on rats at the end of pregnancy (days 18-23). We also analysed the morphology of the luteal cells, to characterize the changes attributable to regression in this organ. Seven biotinylated lectins were used (CON-A, WGA, DBA, SBA, PNA, RCA and UEA-I) following pre-set protocols (ABC method). The average diameter and area of the cells and their nuclei were measured. High reactivity of the luteal cells was observed with CON-A and a lower reactivity with WGA. The capillary endothelium gave positive reactivity with WGA and to a certain extent with SBA, PNA and RCA. Vesicular structures were intensely stained with DBA, and were more abundant in sections from animals with more advanced pregnancy, which could be attributable to cellular debris, on the basis of their morphologic characteristics. There were no significant differences among the cytometric variables analysed in comparisons of the values corresponding to the different days of gestation. These observations, together with previous research, suggest that, on the day of delivery, the corpus luteum of the rat is in the very early stages of structural regression, with no changes at the morphological level, but with changes at the molecular level. 相似文献
247.
Changes in the phagocytic function of peritoneal macrophages from old mice after strenuous physical exercise 总被引:3,自引:0,他引:3
M. de la Fuente M. I. Martin E. Ortega 《Comparative immunology, microbiology and infectious diseases》1990,13(4):189-198
The effect of acute physical exercise (swimming until exhaustion) on the phagocytic function of peritoneal macrophages from old adult BALB/c mice (55 ± 5 weeks old) was studied. Adherence capacity of macrophages to substrate, spontaneous mobility and chemotaxis as well as digestion capacity measured by nitroblue tetrazolium (NBT) reduction in presence of ingested material (latex beads) were not modified with exercise. Adherence to nylon fiber, opsonization and ingestion of Candida albicans (either spontaneous or in presence of serum), ingestion of latex particles as well as nitroblue tetrazolium (NBT) reduction in absence of ingested material (oxidative metabolism measure) were increased in respect to controls with statistically significant differences (P < 0.001) in peritoneal macrophages after the exercise. 相似文献
248.
Nieves Ortega José A Navarro Laura Nicolás Antonio J Buendía María R Caro Laura Del Río Carlos M Martínez Francisco Cuello Jesús Salinas María C Gallego 《Journal of veterinary diagnostic investigation》2007,19(4):421-425
Polymerase chain reaction (PCR) has gained increasing importance as a tool for directly demonstrating the presence of Chlamydophila in the placentas of aborted sheep and goats. However, because of the zoonotic potential of the disease, it is advisable to use fixed materials. To evaluate 4 different DNA extraction protocols in paraffin-embedded sections for PCR, previously immunohistochemically diagnosed placental samples from outbreaks of abortions in goats and sheep were used. The samples were also used to evaluate the effect of the duration of fixation in formalin on PCR. A protocol that uses Tris-HCl pH 8.5 with EDTA and subsequent digestion with proteinase K was found to be an easy protocol for obtaining excellent PCR products for Chlamydophila abortus diagnosis from formalin-fixed and paraffin-embedded specimens. It was also found that if samples are fixed in formalin for more than 2 weeks, the PCR technique is affected more adversely than immunohistochemical methods. 相似文献
249.
Feng Y Ortega Y He G Das P Xu M Zhang X Fayer R Gatei W Cama V Xiao L 《Veterinary parasitology》2007,144(1-2):1-9
Recent studies in the United States reported that approximately 85% of pre-weaned dairy calves were infected with zoonotic Cryptosporidium parvum, whereas only 1-2% of post-weaned calves and 1-2-year-old heifers were infected with this species. Cryptosporidium bovis and Cryptosporidium deer-like genotype were much more prevalent in the post-weaned animals. It is not clear whether the same infection pattern also occurs in other geographic areas. In this study, to determine whether the same Cryptosporidium infection pattern was present in other geographic areas, we genotyped Cryptosporidium specimens collected from two farms in China and India, using specimens from farms in Georgia, USA for comparison. C. bovis was the most common species found in pre- and post-weaned calves in all three areas. In Georgia, the deer-like genotype was found frequently in pre- and post-weaned calves and Cryptosporidium andersoni was found in one post-weaned calf. Both C. bovis and the deer-like genotype were found in the few milking cows examined in Georgia. There were no differences in the small subunit rRNA gene sequences obtained from C. bovis or deer-like genotype among the three areas. One adult yak in China, however, was infected with a species similar to C. bovis, with only three nucleotide mutations in the target gene. All four common bovine Cryptosporidium spp. were differentiated from each other by restriction fragment length polymorphism analysis of PCR products with enzymes SspI and MboII. Thus, both C. bovis and the deer-like genotype are found in all age groups of cattle in diverse geographic areas and host adaptation of C. bovis might have occurred in yaks. 相似文献
250.
Patricio Planells Alandi José M. Tarjuelo Martín-Benito José Ortega Alvarez Maria Casanova Martínez 《Irrigation Science》2001,20(4):189-201
Three fundamental aspects are studied in the design and operating process of a water distribution network for on-demand irrigation. The first determines plot discharge as a function of the average application rate of system, Ars, in sprinkler irrigation or of the equivalent discharge per unit of area in drip/micro irrigation, and according to plot size. The second determines the maximum and minimum demand curves, aspects which have not yet been published. These constitute the possible operating points of the surrounding irrigation network. The third is the dimensioning and regulation of the pumping plant that minimises the investment and operating costs according to usage conditions in the irrigated area, with operation in different hourly periods with different energy costs. The results show that the use of hydraulic valves with limiting flow controllers makes the design of the network easier. Moreover, the installation cost decreases when adjusting the hydrant discharge to the exact size of each plot, thus eliminating excess discharge. The determination of the maximum demand curve allows dimensioning of the pumping plant, as well as its regulation and control in real time after including it into the PID (proportional, integral and derivative) logic of a programmable controller. Moreover, a simplified method for evaluating the energy consumption during the irrigation season is presented, valid for electricity tariffs with different hourly costs. 相似文献