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1.
Bushmeat, defined as meat derived from wild animals, is a potential source of zoonotic pathogens. Bushmeat from restricted animals is illegal to import into the United States under US federal regulations. We reviewed US Centers for Disease Control and Prevention (CDC) port of entry surveillance records from September 2005 through December 2010 and conducted focus group studies to describe trends in and reasons for bushmeat importation into the United States. In total, 543 confiscated bushmeat items were recorded. Half of the confiscated bushmeat items identified were rodents. Africa was the most frequent continent of origin. Seasonality was evident, with bushmeat confiscations peaking in late spring to early summer. Four times more bushmeat was confiscated during an enhanced surveillance period in June 2010 compared with the same period in previous years, suggesting that routine surveillance underestimated the amount of bushmeat detected at US Ports of Entry. Focus groups held in three major US cities revealed that bushmeat importation is a multifaceted issue. Longstanding cultural practices of hunting and eating bushmeat make it difficult for consumers to acknowledge potential health and ecologic risks. Also, US merchants selling African goods, including bushmeat, in their stores have caused confusion among importers as to whether importation is truly illegal. Enhancing routine surveillance for bushmeat and consistent enforcement of penalties at all ports of entry, along with health education aimed at bushmeat importers, might be useful to deter illegal importation.  相似文献   
2.
A monitoring program of the pre-treatment susceptibility of clinical isolates of bacteria from diseased dogs and cats was active between the years 2002 and 2009. Susceptibility of each isolated strain to a panel of nine antibiotics (amoxicillin/clavulanic acid, ampicillin, penicillin, clindamycin, doxycycline, enrofloxacin, marbofloxacin, trimethoprim and trimethoprim/sulfamethoxazole) was assessed. The Minimum Inhibitory Concentration (MIC) of marbofloxacin was also determined by a standardized microdilution technique following CLSI recommendations. In total, 1857 bacterial strains were collected throughout Europe from cases of otitis, respiratory, urinary and dermatological infections. Although bacterial susceptibility varied for each of the antibiotics within the panel, patterns of susceptibility were similar to those described in the literature for comparable time periods and geographical areas. With a clinical resistance varying from 0 to 14.48% against the isolated strains, marbofloxacin susceptibility was very high and remains an effective antibiotic for the treatment of otitis, urinary, respiratory and dermatological infections in companion animals.  相似文献   
3.
The pea root rot complex is a major concern for green pea production worldwide. This study aimed at characterizing its composition and dynamics throughout a cropping season in northern France. To this end, fungi and oomycetes were isolated from green pea plant roots with symptoms sampled at the flowering stage in 22 fields in 2017, and at the pea emergence, elongation and flowering stages in two fields in 2018. Out of 646 isolates collected, 317 were identified using molecular markers. Fusarium oxysporum, F. solani and F. redolens were highly predominant. Pathogenicity tests separated the isolates into four aggressiveness groups. F. solani isolates were the most aggressive. Phylogenetic analysis of their TEF1 sequences showed that they mainly belonged to the F. pisi lineage, and that F. oxysporum isolates were genetically close to isolates from the UK that did not belong to the forma specialis pisi. In addition, several Clonostachys rhizophaga isolates are reported for the first time to cause pea root rot. The oomycetes were rarely found and were represented by a few Pythium spp. isolates. Lastly, this study shows that the fungal and oomycete communities associated with pea root rot change during the cropping season. The level of dissimilarity of the root-rot-associated communities decreased throughout the cropping season towards a more similar composition at the flowering stage, dominated by F. solani, F. oxysporum and F. redolens. The proportion of nonpathogenic to weakly pathogenic isolates decreased progressively during the growing season in favour of moderately to highly pathogenic isolates.  相似文献   
4.
Metabolic and production responses are reported for 72 cows treated with bovine somatotropin (BST) for 30 days starting at day 70 of lactation. Of these 72 cows, 48 had been exposed in the preceding lactation to long-term treatment with BST at 3 dosages and 24 (controls) had not been given BST. Approximately half of the cows in each group were parity-2 cows, the rest were older. Comparisons between groups were made separately for parity-2, and older cows. Analyses, using pretreatment values of each variable as a covariate, indicated that older cows, but not parity-2 cows, significantly (P less than 0.05) increased milk production during treatment. Parity-2 cows, however, had a significantly higher milk fat percentage than controls following treatment. Cows treated with 51.6 or 86 mg BST/d in both parity groups had significantly higher serum-free fatty acids than controls. Estimated net energy balances were significantly lower for older treated cows, but did not significantly differ from controls for parity-2 treated cows. Older cows in the 86 mg of BST/d group tended to have higher concentrations of blood glucose than did older control-group cows. Treatment with BST did not significantly increase serum ketone concentrations in any group of animals, and none of the cows developed clinical ketosis during this period. Estimated net energy balance (ENEB) during treatment was a significant (P less than 0.05) covariate for free fatty acid concentrations in older cows and for milk fat percentage in parity-2 cows. Covariate adjusted analyses, using ENEB during treatment as a covariate, indicated that lipolytic stimuli already acting may be enhanced by treatment with BST, but a negative energy balance was not a necessary precondition for free fatty acid concentrations to increase following somatotropin treatment. Similarly, milk fat percentages for parity-2 treated cows were significantly (P less than 0.05) higher during treatment than controls when ENEB during treatment was used as a covariate. Increased milk fat concentrations in parity-2 treated cows were not associated with significant increases in the ratio of C18:C4-10 milk fatty acids, indicating that increased milk fat resulted from either an increase in incorporation of C18 fatty acids into milk fat coupled with an increase in de novo mammary synthesis of C4-10 milk fatty acids or an increase in C12-16 fatty acids that may arise either from increased tissue mobilization, from diet, or from de novo mammary synthesis.  相似文献   
5.
OBJECTIVE: To assess the effect of maternal cells or cellular components on neonatal immune responses to intracellular pathogens in calves. ANIMALS: 15 Holstein calves. PROCEDURES: Calves were fed whole colostrum, frozen colostrum, or cell-free colostrum within 4 hours after birth. Leukocytes were obtained from calves before feeding colostrum and 1, 2, 7, 14, 21, and 28 days after ingestion. Proliferative responses against bovine viral diarrhea virus (BVDV) and mycobacterial purified protein derivatives were evaluated. Dams received a vaccine containing inactivated BVDV, but were not vaccinated against mycobacterial antigens. RESULTS: All calves had essentially no IgG in circulation at birth, but comparable and substantial concentrations by day 1. Calves that received whole colostrum had enhanced responses to BVDV antigen 1 and 2 days after ingestion of colostrum. In contrast, calves that received frozen colostrum or cell-free colostrum did not respond to BVDV. No differences were identified among the 3 groups in response to mycobacterial antigens. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that transfer of live maternal cells from colostrum to neonatal calves enhanced responses to antigens against which the dams had previously responded (BVDV), but not to antigens to which the dams were na?ve (mycobacterial purified protein derivatives). Results suggested that cell-mediated immune transfer to neonates can be enhanced by maternal vaccination.  相似文献   
6.
Results are presented for monitoring Salmonella infection by bacteriological culture and immune response (enzyme linked immunosorbent assay (ELISA) and haptoglobin) testing of samples collected from beef cattle at a single feedyard sampled over time. A total of 120 beef steers were examined on entry to the feedyard and at days 30, 60, and at time of slaughter (120-150 days). Isolations of Salmonella decreased over time from 40% of the steers sampled at day 0 to 0% at slaughter, whereas serological results varied by serogroup. Seropositivity increased for Salmonella group B up to day 60, and subsequently decreased to about half of the 60-day positivity rate at the time of slaughter. No significant changes in seropositivity were detected during the course of the study for the four other Salmonella serogroups (C1, C3, D1, and E1). Haptoglobin measurements were not a good indicator of Salmonella infection status. Sequential Salmonella testing either by culture, ELISA, or both could be used to monitor pathogen control practices.  相似文献   
7.
European Journal of Plant Pathology - Fusarium verticillioides is a soil-borne plant pathogen of maize plants (Zea mays L.) responsible for major yield losses by causing root, stalk, and ear rot...  相似文献   
8.
Instruments on the Cassini spacecraft reveal that a heat source within Saturn's moon Enceladus powers a great plume of water ice particles and dust grains, a geyser that jets outward from the south polar regions and most likely serves as the dominant source of Saturn's E ring. The interaction of flowing magnetospheric plasma with the plume modifies the particle and field environment of Enceladus. The structure of Saturn's magnetosphere, the extended region of space threaded by magnetic-field lines linked to the planet, is shaped by the ion source at Enceladus, and magnetospheric dynamics may be affected by the rate at which fresh ions are created.  相似文献   
9.
Rabies prevention and control efforts have been successful in reducing or eliminating virus circulation regionally through vaccination of specific reservoir populations. A notable example of this success is the elimination of canine rabies virus variant from the United States and many other countries. However, increased international travel and trade can pose risks for rapid, long‐distance movements of ill or infected persons or animals. Such travel and trade can result in human exposures to rabies virus during travel or transit and could contribute to the re‐introduction of canine rabies variant or transmission of other viral variants among animal host populations. We present a review of travel‐ and trade‐associated rabies events that highlight international public health obligations and collaborative opportunities for rabies prevention and control in an age of global travel. Rabies is a fatal disease that warrants proactive coordination among international public health and travel industry partners (such as travel agents, tour companies and airlines) to protect human lives and to prevent the movement of viral variants among host populations.  相似文献   
10.
A monitoring programme conducted in Europe since 1994 to survey the marbofloxacin susceptibility of bacterial pathogens isolated from cattle has established the susceptibility of bacterial strains isolated before any antibiotic treatment from bovine mastitis and bovine respiratory disease (BRD) cases between 2002 and 2008. Minimum inhibitory concentration (MIC) was determined by a standardised microdilution technique. For respiratory pathogens, Pasteurella multocida and Mannheimia haemolytica isolates (751 and 514 strains, respectively) were highly susceptible to marbofloxacin (MIC≤0.03 μg/ml for 77.39 per cent of the strains) and only 1.75 per cent of M haemolytica strains were resistant (MIC≥4 μg/ml). Histophilus somni isolates (73 strains) were highly susceptible to marbofloxacin (0.008 to 0.06 μg/ml). Mycoplasma bovis MIC (171 strains) ranged from 0.5 to 4 μg/ml. For mastitis pathogens, the majority of Escherichia coli isolates were highly susceptible to marbofloxacin (95.8 per cent of 617 strains). Staphylococcus aureus and coagulase-negative staphylococci (568 and 280 strains) had a homogenous population with MIC centred on 0.25 μg/ml. Streptococcus uberis and Streptococcus dysgalactiae (660 and 217 strains) were moderately susceptible with MIC centred on 1 μg/ml. Marbofloxacin MIC for these various pathogens appeared stable over the seven years of the monitoring programme and was similar to previously published MIC results.  相似文献   
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