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1.
ABSTRACT Fusarium oxysporum f. sp. ciceris and the root-lesion nematode Pratylenchus thornei coinfect chickpeas in southern Spain. The influence of root infection by P. thornei on the reaction of Fusarium wilt-susceptible (CPS 1 and PV 61) and wilt-resistant (UC 27) chickpea cultivars to F. oxysporum f. sp. ciceris race 5 was investigated under controlled and field conditions. Severity of Fusarium wilt was not modified by coinfection of chickpeas by P. thornei and F. oxysporum f. sp. ciceris, in simultaneous or sequential inoculations with the pathogens. Root infection with five nematodes per cm(3) of soil and 5,000 chlamydospores per g of soil of the fungus resulted in significantly higher numbers of propagules of F. oxysporum f. sp. ciceris with the wilt-susceptible cultivar CPS 1, but not with the wilt-resistant one. However, infection with 10 nematodes per cm(3) of soil significantly increased root infection by F. oxysporum f. sp. ciceris in both cultivars, irrespective of fungal inoculum densities (250 to 2,000 chlamydospores per g of soil). Plant growth was significantly reduced by P. thornei infection on wilt-susceptible and wilt-resistant chickpeas in controlled and field conditions, except when shorter periods of incubation (45 days after inoculation) were used under controlled conditions. Severity of root necrosis was greater in wilt-susceptible and wilt-resistant cultivars when nematodes were present in the root, irrespective of length of incubation time (45 to 90 days), densities of nematodes (5 and 10 nematodes per cm(3) of soil), fungal inocula, and experimental conditions. Nematode reproduction on the wilt-susceptible cultivars, but not on the wilt-resistant one, was significantly increased by F. oxysporum f. sp. ciceris infections under controlled and field conditions.  相似文献   
2.
We investigated the effects of liposome encapsulation at prolonging the systemic exposure of buprenorphine following subcutaneous administration in cats. Seven healthy male cats were dosed intravenously with 0.02 mg/kg buprenorphine solution (STD‐BUP), followed 14 days later by a subcutaneous injection of 0.2 mg/kg buprenorphine as a liposomal suspension (SUS‐BUP) containing drug molecules both in liposomes and the suspending vehicle. Buprenorphine time plasma concentration data for both dosing routes were analyzed simultaneously with four compartmental models. Goodness of fit was assessed both graphically and with the Akaike information criterion. The time‐course of intravenous STD‐BUP was biphasic, with a 4.39 h average terminal half‐life. The subcutaneous SUS‐BUP produced plasma buprenorphine concentrations above 0.5 μg/L for more than 96 h, with three distinct peaks in the first 15 h. The model with best fit comprised a central and a peripheral compartment, plus three subcutaneous absorption compartments: one of dissolved drug molecules that were absorbed through a first‐order process, and two of liposome‐encapsulated drug molecules that were transferred to the solution compartment through separate zero‐order processes. Liposomes effectively prolonged the systemic exposure of buprenorphine in cats.  相似文献   
3.
Feline immunodeficiency virus (FIV) is a lentivirus that causes a progressive disruption of immune function in cats. The neuroendocrine and immune systems communicate bidirectionally, mediated by cytokines such as tumour necrosis factor-α (TNF), several interleukins (IL-1, IL-6, IL-10), and through signals induced by the ratio of IL-10 to IL-12. FIV can affect both pituitary adrenal and thyroid axis function. Twenty FIV-infected cats in similar stages of the disease were evaluated for six months. A cross-sectional study in which the twenty cats were divided into two groups was performed. Ten were treated with Zidovudine (ZDV: 5mg/kg/d, PO, q12h, for six months) and 10 were untreated. Plasma concentrations of adrenocorticotropic hormone (ACTH), cortisol, T4, FT4, T3, IL-10, IL-12 and viral load (VL) were evaluated after six months. ACTH was found in significantly lower concentrations (p<0.0001) in the treated group whereas cortisol did not show significant differences between the two groups. Both T4 and FT4 had high values in untreated individuals (p<0.001) compared with Zidovudine treated cats. T3 did not show significant differences between the two groups. Both IL-10 and IL-12 were found in significantly higher concentrations in ZDV treated cats (p<0.001). By contrast, the IL10/IL-12 ratio values were significantly lower in untreated cats. Viral load was significantly lower in the treated cats after six months of therapy, compared with values detected pre-treatment (p<0.002). Untreated cats showed a significant increase of VL (p<0.04) compared with the values at the beginning of the study. In treated cats, VL showed lower numbers of viral copies than in untreated cats (p<0.01). In summary, Zidovudine treatment appeared to contribute to the normalization of both the adrenal and thyroid axes. This effect could be attributed to the decrease observed in VL, resulting in a change in cytokine patterns.  相似文献   
4.
Although the second largest chromosome of the genome, the X chromosome is usually excluded from genome-wide association studies (GWAS). Considering the presence and importance of genes on this chromosome that are involved in reproduction, the aim of this study was to evaluate the effect of its inclusion in GWAS on reproductive traits (scrotal circumference [SC], early pregnancy [P16] and age at first calving [AFC]) in a Nelore herd. Genotype data from 3,263 animals with the above-mentioned phenotypes were used. The results showed an increase in the variances explained by the autosomal markers for all traits when the X chromosome was not included. For SC, there was an increase of more than 10% for the windows on chromosomes 2 and 6. For P16, the effect was increased by almost 20% for windows on chromosome 5. The same pattern was found for AFC, with an increase of more than 10% for the most important windows. The results indicate that the noninclusion of the X chromosome can overestimate the effects of autosomes on SC, P16 and AFC not only because of the additive effect of the X chromosome itself but also because of its epistatic effect on autosomal genes.  相似文献   
5.
6.
We applied capture–recapture methodology (CRC) to data from three surveillance sources (statutory notification, abattoir survey (AS) and fallen stock (FS) survey) to estimate the number of holdings infected with scrapie in Great Britain and to assess the sensitivity of the surveillance network. Between January 1, 2002 and March 31, 2003, 144 holdings were identified by the three sources. Using CRC modelling techniques, we estimated a minimum lower bound for the total number of holdings infected as 642. A biologically plausible positive dependence between the statutory reporting and the fallen stock survey was found statistically significant. The sensitivity of the three sources combined was very low. The integration of the three overlapping sources provided a better understanding of the interactions within the surveillance network. However, the scarcity of the data and reduced overlapping among sources only allowed for very cautious inferences to be drawn about the true proportion of scrapie affected holdings in the national population. Future surveys and surveillance activities should be planned such that the resulting data can be used more effectively as part of CRC modelling approaches.  相似文献   
7.
Salmonella and Yersinia are important enteropathogens in poultry and can affect birds of all ages, including embryos. These food-borne zoonotic enteropathogens are of great economic and medical concern worldwide and are intensely studied in poultry. Information regarding the prevalence of these bacteria in wild birds is scarce and biased toward avian species ecologically linked to humans, which have often been incriminated as both reservoirs and disseminators of these enteropathogens. The prevalence of Salmonella and Yersinia recovered from both the feces and eggs in a population of female pied flycatchers (Ficedula hypoleuca) breeding in nest-boxes in central Spain was evaluated. Salmonella arizonae was recovered from the feces of one female but was not recovered from eggs. Yersinia was not detected in either the feces or eggs. These results may suggest that Salmonella and Yersinia may be uncommon in this population studied and may indicate that these birds are unlikely reservoirs of Salmonella and Yersinia.  相似文献   
8.
To determine the relationship between first service conception rate (FSC) and the postpartum period (PP), 6160 calvings from 2250 crossbred dual-purpose cows were analysed. The effects of breed predominance (BT: Bos taurus and BI: Bos indicus), season of service (dry, intermediate and humid), parity (1 or 2 and more), agroecological region (Sub-humid and Dry Tropical Forest) and milk production were studied. The postpartum period was grouped according to the calving–first service interval as G1 ≤ 60 days (n = 1889); G2 > 60 ≤ 90 days (n = 1436); G3 > 90 ≤ 120 days (n = 1030); and G4 > 120 days (n = 1805). Data were analysed by chi-squared test. The overall mean for FSC was 58.2% and was lower in G1 (p < 0.01). All PP showed a breed effect on FSC, with mean values of 61.6% and 53.3% for BI and BT, respectively. Season of service also affected FSC, which was significantly lower during the humid period: 51.2% versus 57.4% and 61.5% for the intermediate and dry periods (p < 0.01), respectively. Parity and environmental effects were not observed on FSC. Levels of milk yield did influence the FSC, which decreased from 66.7% and 61.0% for milk yields of < 1500 kg and between 1501 and 2000 kg to 46.0% in milk yields > 2000 kg (p < 0.01).  相似文献   
9.
Recently, it has been noted that porcine circovirus type 2 (PCV2) infection adversely affects the protective efficacy of Lapinized Philippines Coronel (LPC) vaccine, an attenuated strain of classical swine fever virus (CSFV), in pigs. In order to investigate the possible mechanisms of the PCV2-derived interference, an in vitro model was established to study the interaction of LPC virus (LPCV) and PCV2 in porcine alveolar macrophages (AMs). The results showed that PCV2 reduced the LPCV infection in AMs and the levels of PCV2-derived interference were dose-dependent. The PCV2-derived interference also reduced the replication level of LPCV in AMs. The full-length PCV2 DNA and its fragment DNA C9 CpG-ODN were involved in the reduction of LPCV infection in AMs, whereas UV-inactivated PCV2 was not. In addition, a moderate negative correlation between the LPCV antigen-containing rate and IFN-γ production was observed, and had a dose-dependent trend with the level of PCV2-inoculation. The results of the present study may partially explain how PCV2 infection interferes with the efficacy of LPC vaccine.  相似文献   
10.
Eco-tourism depending on wildlife is becoming increasingly profitable and landowners are beginning to favor game farming and ecotourism. In these areas, large-scale translocation of wildlife involves a diversity of species and large populations. The African buffalo (Syncerus caffer) is one of the major tourist attractions in Zambia. It accounts for 8.7% and 12.4% of the total animal species hunted in the Game Management Areas and the total hunting revenue earned in Zambia, respectively. It is ecologically an important animal species essential for the purpose of habitat control and facilitating the provision of suitable grazing pastures. However, the rearing of the African buffalo on game ranches has been hampered by its carrier state of the Southern Africa Terroritory (SAT) serotypes of foot and mouth disease virus (FMD). The African buffalo is also known to be a carrier of Theileria parva lawrencei, the causative agent of corridor disease (CD) that continues to have devastating effects on the livestock industry in Zambia. In addition, the importation of buffaloes from countries with populations endemic to bovine tuberculosis is highly restricted. Veterinary regulations in Zambia, strongly advocate against the translocation of buffaloes from protected areas to private ranches for disease control purposes thereby mounting a considerable constraint on the economic and ecological viability of the industry. It is hoped that this review will motivate the relevant government authorities in exploiting ways in which this animal species play a central role in eco-tourism.  相似文献   
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