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21.
Molecular detection of virulence genes in Campylobacter species isolated from livestock production systems in South Africa 下载免费PDF全文
Campylobacter species are a major cause of foodborne bacterial infections in both developed and developing countries worldwide. Campylobacter jejuni is responsible for the majority of infections. This study was conducted to identify virulenceassociated genes in Campylobacter species isolated from livestock production systems in South Africa. A total of 250 fecal samples consisting of cattle(n=50), chickens(n=50), goats(n=50), sheep(n=50) and pigs(n=50) were randomly collected from livestock in Eastern Cape and KwaZulu-Natal provinces of South Africa between April and October 2018. The samples were analyzed for the presence of virulence genes in Campylobacter species using molecular PCR-based methods. It was found that 77 and 23% of Campylobacter jejuni and Campylobacter coli respectively were isolated from all the livestock samples. There were positive significant(P0.05) correlations amongst all the virulence genes that were investigated. Chisquare and Fisher's exact tests were implemented to test for the effect of livestock species on the presence or absence of virulence genes. The study demonstrated that most of livestock species can potentially cause zoonotic infections and food poisoning due to the high prevalence of Campylobacter. The high prevalence of virulence genes highlights the significance of Campylobacter in livestock production systems in South Africa. This requires the implementation of one-health approaches to reduce the impact of foodborne and zoonotic diseases for the welfare of human and animal health. 相似文献
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The liquid limits, degrees of dispersion, and moisture retention of a Tropical Red Earth consisting predominantly of kaolin and iron oxides were independent of the nature of the saturating cation. The same three properties of a Tropical Black Earth consisting predominantly of montmorillonite were dependent upon the nature of the saturating cation, with Na giving the highest values and K the lowest. Ca and Mg gave intermediate and essentially equal values. The effects of the four cations have generally been explained in terms of the balance between attractive and repulsive forces in soil solutions and pastes. Unexpected behaviour due to K saturation has been explained by specific adsorption of K in a manner similar to but weaker than irreversible fixation. Linear regression equations were derived to express the dependence of the three properties on the saturating cations. The regression equations, which were all highly significant, show that the four cations examined were acting independently. Small positive interactions between Na × K, Mg × K, and Ca × K indicated that the effect of K fixation was important only when the Black Earth was nearly saturated with K ions. 相似文献
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Distribution Pattern(s) of Sperm Protein at 22 kDa (SP22) on Fresh,Cooled and Frozen/Thawed Equine Spermatozoa and Expression of SP22 in Tissues from the Testes and Epididymides of Normal Stallions 下载免费PDF全文
LMJ Miller EM Woodward JR Campos EL Squires MHT Troedsson 《Reproduction in domestic animals》2015,50(2):275-282
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In a study of some of the factors that are believed to affect fruit-setting in Eichhornia crassipes under Sudan conditions, the average number of flowers per inflorescence was twelve (range 4–26) while the average number of capsules per inflorescence was 1·5 (range 0–16). The problem of low fruit-setting was suggested to be basically due to the ecological factor of high temperature and low relative humidity. The flowers were preponderantly meso-stylic with the long and short-stylic ‘races’ absent or very rare. Recherches stir la biologic d'Eichhornia crassipes (Mart.) Solms dans le Nil Dans une étude sur quelques-uns des facteurs que l'on suppose actifs sur la mise à fruits de l’Eichhornia crassipes. dans les conditions du Soudan le nombre moyen de fleurs par inflorescence fut de 12 (s'étendent de 4 à 26), cependant que le nombre moyen de capsules par inflorescence fut de 1,5 (s'étendant de 0 à 16). Le probléme de la faible mise à fruit suggere qu'elle pourrait etre due a des facteurs écologiques: température élevée et faible humidity relative. Les fleurs étaient en majorité meso-stylées, les races à long style ou à style court étaient absentes ou tres rares. Generative Vermehrung von Eichhornia crassipes (Mart.) Solms. im Nil In einer Untersuchung über einige Faktoren, von denen angenommen wird, dass sie die Fruchtbildung von Eichhornia crassipes unter sudanesischen Bedingungen beeinflussen, war die durchschnittliche Anzahl von Blüten, 12 Blüten pro Inflorescenz (4–26), wáhrend die durchschnittliche Anzahl von Kapseln nur 1.5 Kapseln pro Inflorescenz war (0–16), Das Problem der geringen Fruchtausbildung wurde folgenden okologischen Faktoren zugeschrieben; hohe Temperatur und niedrige Luftfeuchtigkeit. Bei den Blüten wurden überwiegend Stempel miltlerer Länge gefunden, während die ‘Rassen’ kurzer und langer Stempel nicht oder nur sehr selten anzutreficn waren. 相似文献
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Imazapyr owes its importance in Morocco to its success in controlling the perennial weed Solanumelaeagnifolium Cav., which infests the Tadla area. Persistence and mobility of imazapyr has been studied in two Moroccan soils from the Rabat area, with differing organic matter content (red and organic soils), under laboratory conditions at 75% of their field capacities and 25–28 °C. Residue analysis was performed on the basis of a bioassay test using lentil (Lens culinaris Medic.) as indicator species. The residual activity of imazapyr accounted for 69%, 25%, 50% and 62%, 46%, 66% of the initial activity for the red and organic soils at 1, 5 and 10 mg L?1 respectively. The half-lives varied between 25 and 58 days for the red soil and 55 and 58 days for the organic soil. In the organic soil, imazapyr was highly mobile under the irrigation regime applied. Most of the activity was found in the first 3 × 75 mL of the effluents. A following biotest with the leached soil showed low remaining residual activity. 相似文献
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TATUM EL 《Science (New York, N.Y.)》1959,129(3365):1711-1715
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AIMS: To investigate public attitudes towards barking dogs in New Zealand in order to quantify the extent to which people perceive barking dogs to be a problem, to compare tolerance of barking with that of other common suburban noises, to assess the level of public understanding about the function of barking, to determine risk factors for intolerance of barking and to assess knowledge of possible strategies for the investigation and management of problem barking.METHODS: A 12-page questionnaire was sent to 2,000 people throughout New Zealand randomly selected from the electoral roll. Risk factors for being bothered by barking were examined using logistic regression analysis.RESULTS: A total of 1,750 questionnaires were successfully delivered; of these, 727 (42%) were returned. Among respondents, 356/727 (49.0%) indicated that frequent barking during the day would bother them while 545/727 (75.0%) would be bothered by barking at night. Barking and howling were ranked above other suburban noises as a cause of annoyance. Risk factors for being bothered by daytime barking were not being home during the day, not owning a dog, and considering a dog bite to be a serious health risk. Risk factors for being bothered by night-time barking were not being home during the day, marital status, considering dog bites to pose a serious health risk, and having been frightened by a dog. Overall, 510/699 (73%) respondents understood that barking was a form of communication.Action likely to be taken by 666 respondents hearing frequent barking included notifying and offering to help the owner (119; 17.8%), complaining to the owner (127; 19.1%) or the authorities (121; 18.2%), or doing nothing (299; 48%). Possible responses by 211 dog owners if they had a barking dog included seeking help from dog trainers (59; 28%) or behaviourists (54; 26%), buying an anti-barking device (33; 15%) or getting rid of the dog (20; 10%).CONCLUSIONS: Barking was considered to be potentially disturbing by respondents to this survey. Attitudes towards barking were most influenced by age, dog ownership, past experience with dogs and attitude towards dog bites. Public understanding of the possible reasons for barking and appropriate methods of managing the behaviour when it becomes a problem could be improved by better education and the provision of information through veterinary clinics and social media. 相似文献