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811.
Ângela Piauilino Campos Dayane Francisca Higino Miranda Huanna Waleska Soares Rodrigues Micherlene da Silva Carneiro Lustosa Gustavo Henrique Chaves Martins Ana Lys Bezerra Barradas Mineiro Vanessa Castro Sérgio Santos Azevedo Silvana Maria Medeiros de Sousa Silva 《Tropical animal health and production》2017,49(5):899-907
Leptospirosis is an endemic disease in Latin America, caused by pathogenic bacteria of the genus Leptospira. It is considered one of the main causes responsible for the negative economic impact on global livestock by causing reproductive problems. The research aimed to determine the prevalence of leptospirosis in cattle, sheep, and goats at consorted rearing in the micro-region of Teresina, Piauí state, northeastern Brazil, as well as to identify prevalent serovars and risk factors associated with seroprevalence. Serum samples were analyzed in 336 sheep, 292 goats, and 253 cattle using microscopic agglutination test (MAT). Overall, 378 samples were positive to MAT, with seroprevalence of 42.9%. The prevalences in cattle, sheep, and goats were 50.5, 40.5, and 34.6%, respectively. All herds presented at least one seropositive animal; the Hardjo/Wolffi serovar association was the most common in cattle and Icterohaemorrhagiae in goats and sheep. Beef production (OR?=?4.9), cattle herd over 35 animals (OR?=?4.0), feeding on pasture (OR?=?6.4), weir and/or stream as water source (OR?=?2.1), and no veterinary services (OR?=?2.9) were risk factors for cattle infection. For sheep, intensive management system (OR?=?5.3), suspended slatted facilities (OR?=?2.2), more than 20 sheep in reproductive age (OR?=?1.9), and absence of deworming (OR?=?3.5) were the risk factors, while for goats, the identified risk factors were sheep herd over 52 animals (OR?=?1.9) and no veterinary services (OR?=?1.8). We conclude that the infection was spreading in consorted herds in this region. Thus, it would be interesting and important to conduct educative activities to farmers on the economic impacts of this disease and the need of preventive and control strategies mainly focused on sanitary measures and animal handling. 相似文献
812.
Manoel Delintro de Castro Neto Daniel Valadão Silva Autieres Teixeiras Faria Antônio Alberto da Silva Gustavo Antônio Mendes Pereira 《Archives of Agronomy and Soil Science》2017,63(7):897-906
Herbicides with high mobility can leach to deeper layers of the soil and to contaminate underground aquifers. The potential of herbicide leaching in soil can be monitored by chromatography or bioassay methods. This study evaluated the leaching of imazethapyr, imazapic and its commercial mixture (imazethapyr + imazapic) in three tropical soils via a bioassay method. The herbicides were applied in a polyvinyl chloride column and an 80 mm rainfall was simulated. The bioindicator species sorghum (Sorghum vulgare) BRS 655 was sown. Imazethapyr, imazapic and the commercial herbicide mixture showed high leaching in the soils. The presence of imazethapyr and the commercial mixture was detected up to 25 cm deep in Haplic Plinthosol and Oxisol. Imazapic showed less leaching to tree soil, being found at depth 10–15 cm. The pH, texture and iron oxide amount levels affected herbicide leaching. The mobility of the herbicides imazethapyr and imazapic in the Haplic Plinthosol and the Oxisol at depth 25 cm indicates a high risk of groundwater contamination. 相似文献
813.
Jaqueline B. Azevedo Gustavo S. Silva Priscylla S. Rocha Letícia C. Pitchenin Valéria Dutra Luciano Nakazato Anderson Castro Soares de Oliveira Caroline A. Pescador 《Tropical animal health and production》2017,49(2):311-316
Ureaplasma diversum infection in bovine females may result in various reproductive problems, including granular vulvovaginitis, abortion, weak calves, salpingitis, and spontaneous abortion. The presence of U. diversum in a dairy bovine population from midwestern Brazil has not been established. The aim of this study was to determine whether U. diversum was present in dairy cattle from midwestern Brazil using polymerase chain reaction (PCR). Vulvovaginal mucus was analyzed from 203 cows located in six municipalities in the north region of Mato Grosso State, Brazil. A total of 25% of dairy cows with vulvovaginitis were positive for U. diversum. The factors evaluated were included in a multivariable logistic regression model with the presence of at least one positive cow in the herd serving as the dependent variable. Three variables were significantly associated with a U. diversum-positive PCR and were included in the final multivariable model: number of parities, vulvar lesions, and reproductive problems. For each new parity, the chance of U. diversum infection decreased 0.03-fold, indicating that cows with the highest number of parities were more protected. The presence of vulvar lesions was increased 17.6-fold in females positive for U. diversum, suggesting that this bacterium could be related to the red granular lesions in the vulvar mucosa, whereas reproductive problems were increased 7.6-fold. However, further investigations should be conducted to ascertain the effects of U. diversum in association with other mycoplasma species in the herds studied. 相似文献
814.
We screened for Japanese Black and Holstein bull sire samples to detect single nucleotide polymorphisms (SNPs) involving animo‐acid substitutions in the bovine prion gene in the entire coding region of the PRNP gene. Although three silent SNPs were found, we could not detect any SNP with animo‐acid substitution. We also examined the polymorphism of the octapeptide repeat number in these samples. There was no homozygous bull with repeat number 5. The frequency of heterozygous (6/5) bulls was 8% in the Japanese Black bull and 4% in the Holstein bull, respectively. The bull samples used in this study contain popular elite sires, so it appears that the polymorphisms of prion protein (PrP) are rather difficult to find in these two breeds in Japan, except for polymorphism of the octapeptide repeat number. 相似文献
815.
Pandolfi JM Bradbury RH Sala E Hughes TP Bjorndal KA Cooke RG McArdle D McClenachan L Newman MJ Paredes G Warner RR Jackson JB 《Science (New York, N.Y.)》2003,301(5635):955-958
Degradation of coral reef ecosystems began centuries ago, but there is no global summary of the magnitude of change. We compiled records, extending back thousands of years, of the status and trends of seven major guilds of carnivores, herbivores, and architectural species from 14 regions. Large animals declined before small animals and architectural species, and Atlantic reefs declined before reefs in the Red Sea and Australia, but the trajectories of decline were markedly similar worldwide. All reefs were substantially degraded long before outbreaks of coral disease and bleaching. Regardless of these new threats, reefs will not survive without immediate protection from human exploitation over large spatial scales. 相似文献