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21.
The influence of fruit ripeness (half ripe, fully ripe, overripe) at the time of seed extraction on seed germination behaviour, at 25 °C and 13 °C, was studied in two Spanish pepper cultivars for canning. Seeds from half ripe fruits had a poorer behaviour than those taken from fully ripe fruits, especially at 13 °C. Room ripening and overripening of half ripe fruits improved the germination behaviour of the seeds although this behaviour was poorer than that of seeds extracted from fully ripe fruits that were allowed to overripen. Overripening of fully ripe picked fruits slightly improved germination behaviour.  相似文献   
22.
A unique, "honeycomb" pattern was found on ultrasonographic evaluation of the liver of 5 dogs with canine superficial necrolytic dermatitis (hepatocutaneous syndrome). This pattern consisted of variably-sized, hypoechoic regions measuring 0.5–1.5 cm in diameter surrounded by highly echogenic borders. Histologically, the hypoechoic regions corresponded to distinct regenerative nodules bounded by severely vacuolated (fat-laden) hepatocytes, numerous bile ductules, and a network of reticulin and fine collagen fibers representing remnants of collapsed hepatic lobules. While certain features of the architectural disruption were characteristic of cirrhosis, the lesion lacked the extensive fibrosis and reduced liver size usually associated with chronic cirrhosis. To our knowledge, this hepatic ultrasonographic pattern has only been seen with canine superficial necrolytic dermatitis. Therefore, it appears to be pathognomonic in a dog with questinable skin lesions. A liver biopsy is required to confirm the unique histopathologic features of the hepatopathy found in this syndrome.  相似文献   
23.
Chlamydophila abortus is the aetiological agent of enzootic abortion in small ruminants in which it infects the placenta to cause abortion during the last trimester of gestation. In a mouse model, a Th1 immune response involving IFN-gamma production and CD8+ T cells is necessary for the infection to be resolved. The authors previously demonstrated that infection with Nippostrongylus brasiliensis, a rodent gastrointestinal nematode extensively used in experimental models to induce Th2 responses, alters the specific immune response against C. abortus infection, increasing bacterial multiplication in liver and reducing specific IFN-gamma production. The aim of the present work was to clarify whether a Th2 immune response has any influence on the success of vaccination using both inactivated and attenuated vaccines. The results showed that the Th2 response established prior to vaccination did not influence the induction of protection offered by the vaccines. However, the effectiveness of this protective response can be altered, depending on the adjuvant employed in the inactivated vaccines, when the Th2 response is established after vaccination, just before challenge with C. abortus.  相似文献   
24.
Multifocal interstitial nephritis in pigs has been associated with several infectious agents. The objective of the present study was to investigate several different potential infectious agents associated with "white-spotted" kidneys in pigs suffering from wasting at slaughter (aged 6-8 months). Twenty-nine case kidneys (with a "white-spotted" gross appearance) classified into 3 macroscopic lesional grades, and 15 control kidneys (lacking gross lesions), were obtained from a pig abattoir. Laboratory analyses to detect potential associations with the aforementioned pathological condition with Leptospira spp., porcine circovirus type 2 (PCV2), porcine parvovirus (PPV), porcine reproductive and respiratory syndrome virus (PRRSV), and bacteria, were carried out. Microscopically, interstitial nephritis with a lymphofollicular inflammatory pattern (follicular nephritis) was observed in both case and control kidneys, with a higher frequency seen in the former ones. No leptospires were identified, although antibodies to the Pomona and Bratislava serovars were detected. Some pyogenic bacteria were also isolated from both case and control kidneys. PCV2 nucleic acid was only detected in 1 case kidney. PRRSV antigen was not found in any tested sample. Some pigs were tested positive for PPV by serology. Apparently, none of the studied agents were specifically associated as being the potential cause of the renal lesions in the studied wasted pigs. The fact that these chronic lesions may have been the consequence of a previous infection with one of these studied microorganisms, or more, and eventually with other non-tested infectious agents during the growing-finishing period, cannot be ruled out.  相似文献   
25.
The Nc-Spain 7 isolate of Neospora caninum, which was newly obtained from an asymptomatic congenitally infected calf, demonstrated a similar virulence as Nc-1 strain in mouse models. The aim of this study was to characterize the pathogenesis of Nc-Spain 7 isolate in cattle after experimental infection at 65 days of gestation. For this purpose, thirteen pregnant heifers were divided into three groups as follows: group A: 7 heifers inoculated with 1×10(8) tachyzoites of Nc-Spain 7 isolate; group B: 4 heifers inoculated with 1×10(8) tachyzoites of Nc 1 strain; and group C: 2 heifers received PBS. Serum samples were collected weekly and heparinized blood samples were collected three times (0, 28 and 42 days after inoculation) by jugular venipuncture. Placenta and fetal tissue samples were collected at time of necropsy. Specific antibody response in the dams was tested by IFAT, indirect ELISA, and rNcGRA7 and rNcSAG4 based-ELISA. Specific antibody response in fetal fluids was tested by IFAT. IFN-γ production was measured after in vitro culture of PBMC and the supernatant was assessed using a commercial kit (BOVIGAM). A significant increase in N. caninum antibody responses was detected in groups A and B by IFAT and by i-ELISA from day 14 after inoculation onwards. Besides, antibody response against rNCGra7 protein was also detected in all inoculated heifers by rNcGra7-based ELISA. Four fetuses from group A and one from group B were aborted between 3 and 5 weeks after infection. In the recovered fetuses, only 3 out of 4 fetal fluids from fetuses of group A and 1 out of 3 of group B were seropositive by IFAT, but all of them were positive by PCR. Transplacental transmission could be determined in all fetuses from groups A and B by PCR and/or IHC. Heifers of group C and their fetuses remained negative by all techniques. The results of this study demonstrate that the NC-Spain 7 isolate could be transmitted transplacentally, and produced fetal death and abortion in cattle.  相似文献   
26.
This article analyzes curriculum offerings related to aquaculture and/or aquatic-animal health taught in veterinary medical schools or colleges in Mexico. The information database of the Mexican Association of Schools and Colleges of Veterinary Medicine and the Web sites of veterinary institutions indicate that 60% of veterinary colleges include courses related to aquaculture in their curriculum, but most of these are optional courses. There are few specialized continuing education programs or graduate level courses. There is also a lack of veterinary participation, in both public and private sectors, in aquatic-animal health. It is evident that there should be a greater involvement by the veterinary profession in Mexico's aquaculture to ensure food production in a safe and sustainable manner; to achieve this, veterinary medical institutions must include more aquaculture and aquatic-animal health courses in their curricula.  相似文献   
27.

Tree growth and wood density are influenced by forest management. Nevertheless, few studies have evaluated their variability responses to fertilizer treatments at inter-annual, inter-tree and stand-production levels. Therefore, the annual ring width (RW) and density (RD) of sixty 17-year-old-Pinus taeda trees fertilized with six doses of composted pulp-mill sludge (CPMS) were analyzed. Ten trees for each treatment were felled and from which wood discs were taken at different trunk heights. The annual RW and RD were provided by X-ray microdensitometry, synchronized and the trunk basic specific gravity (SGB) and biomass calculated. The effects of CPMS treatments were explored using interaction of variables RW and RD with cambial age, diameter, trunk SGB and biomass production. Trees treated with CPMS grow faster, increasing their biomass (up to 108%), presenting lower wood density values (significant up to the 6th year) and reaching the mature wood later than untreated trees. Furthermore, the potential use of RW and RD in allometric equations showed good accuracy to predict trunk SGB and biomass. Altogether, our results indicated that ring width and density revealed the impacts of fertilization treatment on wood quality and production. Our study also provides useful information for forest managers on the fertilization monitoring process.

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28.
The vascular endothelial growth factor (VEGF) is essential for follicular development by promoting follicular angiogenesis, as well as for the proliferation and survival of granulosa cells. The biological effects of VEGF are regulated by two membrane receptors, VEGFR1 and VEGFR2, and two soluble receptors, sVEGFR1 and sVEGFR2, which play an antagonistic role. Thus, the objective of this study was to identify the mRNA expression pattern of total VEGF, VEGFR1, VEGFR2, sVEGFR1 and sVEGFR2 in bovine preselected follicles (PRF) and post‐selected follicles (POF). The mRNA expression of these five genes in both granulosa cells (GC) and theca cells (TC) was compared between follicles classified as PRF and POF based on their diameter and on their ratio of estradiol/progesterone (E2/P4). Results showed a lower expression of mRNA of sVEGFR1 and sVEGFR2 in POF than in PRF (p < .05). Regarding the mRNA expression of total VEGF, VEGFR1 and VEGFR2, there was no difference between POF and PRF follicles (p > .05). Our results showed that the mRNA expression of VEGFR2 and sVEGFR1 was more abundant than the expression of VEGFR1 and sVEGFR2, while GC was the main source of mRNA for total VEGF. On the other hand, TC was the follicular compartment where the receptors were most expressed. Our results suggest that non‐dominant follicles maintain a greater concentration of the mRNA expression of both membrane and soluble VEGF receptors. On the other hand, follicular dominance is related to a reduction in the mRNA expression of sVEGFR1 and sVEGFR2, which may favour VEGF binding with VEGFR2 and, hence, improve the follicular health and development.  相似文献   
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