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1.
Eric Lim Teik Chung Michael Predith Frisco Nobilly Anjas Asmara Samsudin Faez Firdaus Abdullah Jesse Teck Chwen Loh 《Tropical animal health and production》2018,50(8):1727-1732
Brachiaria decumbens is an extremely productive tropical grass due to its aggressive growth habit and its adaptation to a varied range of soil types and environments. As a result of the vast availability, treated B. decumbens demonstrates as a promising local material that could be utilised as an improved diet for sheep and goats. Despite the fact that the grass significantly increases weight gains in grazing farm animals, there were many reports of general ill-thrift and sporadic outbreaks of photosensitivity in livestock due to the toxic compound of steroidal saponin found in B. decumbens. Ensiling and haymaking were found to be effective in removing toxin and undesirable compounds in the grass. Biological treatments using urea, activated charcoal, polyethylene glycol, and effective microorganisms were found to be useful in anti-nutritional factor deactivation and improving the nutritive values of feedstuffs. Besides, oral administration of phenobarbitone showed some degree of protection in sheep that fed on B. decumbens pasture. In this review, we aim to determine the effect of B. decumbens toxicity and possible treatment methods on the grass to be used as an improved diet for small ruminant. 相似文献
2.
Daniel A. Truchado Michaël A. J. Moens Sergio Callejas Javier Pérez-Tris Laura Benítez 《Veterinary research communications》2018,42(2):111-120
Papillomaviruses are non-enveloped, DNA viruses that infect skin and mucosa of a wide variety of vertebrates, causing neoplasias or simply persisting asymptomatically. Avian papillomaviruses, with six fully sequenced genomes, are the second most studied group after mammalian papillomaviruses. In this study, we describe the first oral avian papillomavirus, detected in the tongue of a dead Yorkshire canary (Serinus canaria) and in oral swabs of the same bird and other two live canaries from an aviary in Madrid, Spain. Its genome is 8,071 bp and presents the canonical papillomavirus architecture with six early (E6, E7, E1, E9, E2, E4) and two late open reading frames (L1 and L2) and a long control region between L1 and E6. This new avian papillomavirus L1 gene shares a 64% pairwise identity with FcPV1 L1, so it has been classified as a new species (ScPV1) within the Ethapapillomavirus genus. Although the canary died after showing breathing problems, there is no evidence that the papillomavirus caused those symptoms so it could be part of the oral microbiota of the birds. Hence, future investigations are needed to evaluate the clinical relevance of the virus. 相似文献
3.
Leonard Omadang Martin Chamai Emmanuel Othieno Andrew Okwi Francis Olaki Inangolet Francis Ejobi Peter Oba Michael Ocaido 《Tropical animal health and production》2018,50(1):11-17
A cross-sectional study was done from March 2013 to May 2014 to assess knowledge, attitudes, and practices towards cystic echinococcosis (CE) or hydatidosis among selected pastoral and agro-pastoral communities in Uganda. A structured questionnaire was administered to 381 respondents. Multivariate logistic regression analysis was done to find the relationship between knowledge about CE and factors such as age, sex, and level of education across all regions. The odds ratio and confidence interval were used to determine the difference in responses across regions. It was shown that age above 36 years was significantly (p < 0.001) associated with awareness about CE in livestock. Likewise, uneducated (p < 0.0001) and agro-pastoralists (p = 0.01) were significantly less knowledgeable than the educated and pastoralists across all regions. The overall knowledge towards CE in livestock was low 17.8% (95% CI = 14.0–21.6). Dog ownership was high and they never dewormed their freely roaming dogs. Dogs shared water with livestock. In conclusion, knowledge about CE in livestock was low across all regions. Therefore, public health education and formulation of policies towards its control by the relevant stakeholders should be done. Also, the true prevalence of CE in livestock needs to be done so that the magnitude and its public health significance are elucidated. 相似文献
4.
A蛋白斑点免疫金染色和双抗体夹心酶联检测齿兰环斑病毒的比较 总被引:15,自引:1,他引:15
A蛋白斑点免疫金染色检测齿兰环斑病毒提纯病毒的灵敏度为1.56 ng/μl,检测病汁液的稀释倍数为640倍.同时采用碱性磷酸酯酶标记抗体IgG.IgG包被酶联板的浓度为1 μg/ml,酶标抗体以1 /1000稀释使用.DAS-ELISA技术检测ORSV提纯病毒的灵敏度为0.048 ng/μl,检测病汁液的稀释倍数为20480倍. 相似文献
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为研究甘油超临界水气化制氢过程及转化动力学,采用正交试验和单因素试验,在连续式反应器中,分析不同工艺参数对甘油超临界水气化气体产物分布和气化转化效率的影响,对气体产物进行气相色谱分析。利用集总动力学研究方法,优化甘油超临界水气化转化动力学模型,增加CO2甲烷化反应路径,探讨甘油超临界水气化过程中动力学参数和气相产物生成及消耗路径。结果表明:甘油超临界水气化制氢的最佳工况为温度600 ℃、甘油浓度0.015 mol/L、压力27 MPa和停留时间18 s,此时H2产量为2.411 mol/mol,气化效率为76.49 %。单因素试验结果可知,较高反应温度和压力、较低原料浓度和适当延长停留时间有利于提高H2产量和甘油气化效率。反应速率常数随着温度的升高而增加,甘油热解路径Ⅱ和中间体蒸汽重整路径Ⅰ的活化能分别高于甘油热解路径Ⅰ和中间体蒸汽重整路径Ⅱ。H2主要通过甘油热解和水气变换反应生成,CO2主要通过甘油热Ⅰ和水气变换反应生成,CO2甲烷化是H2和CO2消耗的主要路径。中间体热解是CO和CH4的主要生成路径,CO的主要消耗路径是水气变换反应。 相似文献
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8.
ABSTRACT: The present study reports the annual variation in consumption of the sea urchin Strongylocentrotus intermedius by avian predators on a rocky shore where the culture of sea urchins has been conducted. Carrion crow and a few gull species were the most abundant avian predators and consumed a large number of sea urchins. Crows consumed mostly natural sea urchins, approximately 36 kg ww/ha per year on the intertidal rocky bench, but the gull species consumed mostly cultured sea urchins, approximately 100 kg ww/ha per year in the culture area. The seasonal variation in the amount of sea urchins consumed by crows was higher than that by the gull species, presumably because of the difference in foraging behavior in association with the seasonal tidal cycle. The natural sea urchins consumed are an allochthonous input from the subtidal to the intertidal habitat, and thus, crow predation may not affect the natural and the cultured populations of the sea urchin. The gull species consumed much of the cultured sea urchin, and thus, may be regarded as an effective predator causing damage to sea urchin culture. The results suggest that further studies are needed to determine why the gull species selectively feed on cultured sea urchins. 相似文献
9.
One hundred and forty-seven Chinese barley varieties maintained at the Gene Bank of the National Barley Improvement Centre,
Zhejiang, and 84 progenies from these varieties were tested at the seedling stage for their reaction to 32 selected pathotypes
of Blumeria graminis f. sp. hordei. Eighteen resistance spectra were identified comprising single or combined resistances from eight known (Ml(Bw), Ml(Ch), Mla7, Mla8, Mla9, Mla13, MlaRu4 and Mlg) and six unknown resistance genes. The most frequent gene was Ml(Bw), which was found in 69 varieties and previously detected in only a few European winter barley varieties. The genes Mla8 and Ml(Ch) were also often present, but other resistance genes were rare. After inoculation, considerably fewer pathogen colonies were
observed in ‘Aiganqi’ and one line of ‘Tong5’. Twenty varieties were composed of lines with different resistance genes. China
is likely to be a region of origin of the genes Ml(Bw), Mla7, as well as three unknown genes found in original landraces and perhaps another three unknown genes detected in cultivars
bred in China. The resistances of varieties from the Zhejiang province and those originating from 11 other Chinese provinces
were quite different. Unfortunately, none of the varieties are promising sources of resistance to powdery mildew and China
does not seem to be a region suitable for identifying such sources. 相似文献
10.
Sarah I. Beldin Bruce A. Caldwell Phillip Sollins Elizabeth W. Sulzman Kate Lajtha Susan E. Crow 《Biology and Fertility of Soils》2007,43(6):837-841
The cation exchange capacity (CEC) of a soil depends on the type and amount of both mineral and organic surfaces. Previous
studies that have sought to determine the relative contribution of organic matter to total soil CEC have not addressed differences
in soil organic matter (SOM) composition that could lead to differences in CEC. The objectives of this study were (1) to compare
the CEC of two distinct SOM pools, the “light fraction (LF)” composed of particulate plant, animal, and microbial debris,
and the “heavy fraction (HF)” composed of mineral-bound organic matter; and (2) to examine the effects of differences in aboveground
vegetation on CEC. Soil samples were collected from four paired grassland/conifer sites within a single forested area and
density fractionated. LF CEC was higher in conifer soils than in grassland soils, but there was no evidence of an effect of
vegetation on CEC for the HF or bulk soil. LF CEC (but not HF CEC) correlated well with the C concentration in the fraction.
The mean CEC of both fractions (per kg fraction) exceeded that of the bulk soil; thus, when the LF and HF CEC were combined
mathematically by weighting values for each fraction in proportion to dry mass, the resulting value was nearly twice the measured
CEC of bulk soil. On a whole soil basis, the HF contributed on average 97% of the CEC of the whole soil, although this conclusion
must be tempered given the inflation of CEC values by the density fractionation procedure. 相似文献