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221.
After improvement of hygiene protocols on boots in a bovine operation (farm A) in Ibaraki, Japan in September 2017, mortality of calves and the detection of 4 viral pathogen indicators, including bovine rotavirus A (RVA), became significantly low for one year. Subsequently, in the present study, these indicators and mortality were monitored and confirmed all were still low, except for the detection rate of bovine RVA in calves less than 3 weeks old. The present study aimed to investigate G and P genotypic profiles of RVAs in farm A from 2018 to 2020. Molecular analysis using semi-nested multiplex RT-PCR of positive RVAs (n=122) and sequencing of selected samples revealed the presence of G6, G8, G10, P[1], P[5] and P[11] genotypes and the prevalence of G and/or P combination and mixed infections. The most common combination of G and P types was G10P[11] (41.8%), followed by mixed infection with G6+G10P[5] (11.5%). Phylogenetic analysis of RVAs showed clustering with bovine and other animal-derived RVA strains, suggesting the possibility of multiple reassortant events with strains of bovine and others animal origins. Noteworthy as well is that vaccinated cattle might fail to provide their offspring with maternal immunity against RVA infections, due to insufficient colostrum feeding. Our findings further highlight the importance of RVA surveillance in bovine populations, which may be useful to improving effective routine vaccination and hygiene practices on bovine farms.  相似文献   
222.
Analysis of environmental samples obtained from the Live Poultry Markets (LPMs) of Dhaka City, Bangladesh, has revealed that the highest degree of prevalence of highly pathogenic avian influenza A (HPAI, H5N1), besides other subtypes of the LPAI virus, poses the plausible risk of transmission of these viruses between human and poultry species. The present study was conducted using the OIE risk analysis framework to assess the risk level of each pathway successively. The estimated risk parameters were integrated towards to obtain the overall risk level for each specific HPAI transmission pathway using the matrix adapted by Cristobel Zepeda accompanying other expert consultations. The relevant data obtained from published and unpublished sources, together with survey data of field observations, were used to formulate and confirm the risk pathways and their associated risks. The results revealed that the risk of the release of the HPAI virus was medium when exposure was high. Additionally, the consequence would be considered very high with a medium degree of uncertainty for all parameters. Ultimately, the overall risk for transmission was estimated as medium with a medium degree of uncertainty. The findings of this study reveal that there is a significant threat that HPAI virus transmission could occur among poultry and humans and effectively sustain within the environment of the LPMs. Our findings are primarily focused on public health considerations, the hygienic slaughter of poultry and the relevant cleaning and sanitation practices conducted in the LPMs to support evidence‐based decision‐making processes. The findings of the study have the potential to be used to formulate effective risk reduction measures and can be further adapted in low‐resource settings without major infrastructural changes required of the LPMs. All of which would reduce the risk of HPAI virus release and further lessen the degree of exposure and transmission in established LPMs.  相似文献   
223.
Milk, especially colostrum, contains different kinds of macromolecules abundantly, such as immunoglobulin G (IgG), lactoferrin (Lf), transferrin (Tf), and growth factors. These are essential for the development and maintenance of health, which greatly depends on the absorption and transportation of macromolecules to the target organs. To evaluate the macromolecular transport, and concentrations in plasma and cerebrospinal fluid (CSF), colostrum was fed to newborn calves followed by milk and milk replacer, and maintained up to the 4th week under farm conditions. Plasma and CSF were collected at different times, and were analyzed for Lf, Tf, IgG and iron concentrations. Lf, Tf and IgG concentrations were steeply increased in plasma and CSF after colostrum feeding, and fluctuating patterns were observed during the experiments. Furthermore, intraduodenal administration of bovine Lf alone in young calf experiments revealed that the Lf concentration reached a peak at 4 hr, and was 7 and 4 times higher than preadministration in plasma and CSF, respectively. To explore the transport mechanism of Lf into CSF in young calves, epithelial membranes of the choroid plexus were prepared and a binding assay for Lf receptors (Lf-R) was carried out with 125I-Lf. The saturation kinetics revealed that the Bmax of epithelial membranes was 26.15 nmol/mg protein with a Kd of 0.11 microM, which also showed that Lf-R is saturable and specific. Scatchard plot transformation showed the presence of a single type of Lf-R in the choroid plexus. These results suggest that Lf is transported into the CSF through receptor mediated transcytosis in young calves, and that Lf may play an important role(s) in brain function.  相似文献   
224.
Several statistical models used in genome‐wide prediction assume uncorrelated marker allele substitution effects, but it is known that these effects may be correlated. In statistics, graphical models have been identified as a useful tool for covariance estimation in high‐dimensional problems and it is an area that has recently experienced a great expansion. In Gaussian covariance graph models (GCovGM), the joint distribution of a set of random variables is assumed to be Gaussian and the pattern of zeros of the covariance matrix is encoded in terms of an undirected graph G. In this study, methods adapting the theory of GCovGM to genome‐wide prediction were developed (Bayes GCov, Bayes GCov‐KR and Bayes GCov‐H). In simulated data sets, improvements in correlation between phenotypes and predicted breeding values and accuracies of predicted breeding values were found. Our models account for correlation of marker effects and permit to accommodate general structures as opposed to models proposed in previous studies, which consider spatial correlation only. In addition, they allow incorporation of biological information in the prediction process through its use when constructing graph G, and their extension to the multi‐allelic loci case is straightforward.  相似文献   
225.
ABSTRACT

This paper discusses fish consumption and preference patterns for fish species by income groups, and by urban/rural divide in Bangladesh, China, India, Indonesia, the Philippines, Thailand, and Vietnam. The analysis is based on primary data collected by the WorldFish Center and its partner institutes by means of a survey of 5,931 households in the selected countries. The FAO database and other published materials were also used to analyze trends in fish consumption. Freshwater fish species constitute a major share in total per capita fish consumption in most of these countries. Pelagic and demersal marine fish are the main contributor to per capita total fish consumption in the countries with longer coastal boundaries (such as Indonesia, the Philippines and Thailand), and in the coastal regions within each country. Results suggest that fish contributes between 15% and 53% of the total animal protein intake in these countries. Fish consumption varies widely with economic position of the households, in terms of both per capita consumption and type of fish species. Per capita fish consumption increases with increase in income. The share of fish protein in total animal protein expenditure is higher for lower income groups, demonstrating their dependence on fish as a source of animal protein. Poor people consume mostly low-price fish and rich people spend a significant portion of their fish budget on expensive fish. Per capita fish consumption is substantially higher in rural areas than in urban areas.  相似文献   
226.
Studies of the effects of host-immunity on the life cycle of Hyalomma rufipes were carried out by allowing the ticks to feed on New Zealand white rabbits under laboratory conditions. The immunity of the rabbit host significantly affected the life cycle of this tick, reducing the percentage recovery of engorged females, their engorged weights and the total number of eggs laid by these females. The viability of the eggs laid by them was also considerably reduced compared to the eggs laid by females fed on naive rabbit hosts. The effects of host immunity were also revealed in the tendency towards three-host development of this species, which otherwise behaved as a two-host tick when fed on non-immune rabbit hosts.  相似文献   
227.
The ethanol leaf extract of Cymbidium aloifolium (L.) was evaluated for its analgesic and antiinflammatory activities. The extract, at the dose of 200 and 400 mg kg(-1) body weight, exerted the analgesic activity by observing the number of abdominal contractions and anti-inflammatory activity against Carrageenin induced paw edema in mice by measuring the paw volume. The ethanolic extract of Cymbidium aloifolium (L.) showed statistically significant (p < 0.05) reduction of percentage of writhing of 33.57 and 61.31% at 200 and 400 mg kg(-1) oral dose, respectively, when compared to negative control. The Ethanolic plant extract also showed significant (p < 0.05) dose dependent reduction of mean increase of formation of paw edema. The results of the experiment and its statistical analysis showed that the ethanolic plant extract had shown significant (p < 0.05) dose dependent analgesic and anti-inflammatory activities when compared to the control.  相似文献   
228.
Parental condition‐dependent offspring fitness is a well‐discussed issue in animal breeding research, while offspring environment and its interaction with parental condition are currently another very interesting topic to investigate the plasticity of phenotypic traits across an environmental gradient. The present study was, therefore, conducted following a half‐sib breeding design to test the effects of (a) paternal body size, (b) offspring feeding strategy (everyday and every other day) and (c) their interactions on fitness‐related traits (e.g., survival, total length and body area) of offspring of a commercially important aquaculture species, the Indian major carp (Labeo rohita). The analysis revealed that paternal body size had significant effects on offspring survival rate and total length, while no significant influence was found in body area. The study also showed that the offspring feeding strategy significantly affected all offspring traits. Interestingly, the study unveiled the significant interactive effects of paternal condition and offspring feeding for offspring survival rate and total length. These findings suggest that paternal size, offspring rearing environment and their interactions can influence offspring fitness‐related traits which are very essential information for the sustainable production of good quality larvae under variable dietary conditions.  相似文献   
229.
This study was carried out to investigate the effects of different levels of clove bud (Syzygium aromaticum) powder and vitamin E on serum lipid profile, enzyme activities and antioxidant indices, as well as hepatic biochemical and histological alterations in laying hens receiving different n‐6 to n‐3 ratios. A total of 160 laying hens, 43 weeks of age, were allotted to 8 experimental diets with 5 cages of 4 birds each. Dietary treatments consisted of two ratios of n‐6 to n‐3 (16.71 and 2.35), three levels of clove bud (0.0, 2.0 and 4.0 g/kg) and a high vitamin E level (200 mg/kg, as a positive control in each level of n‐6 to n‐3 ratio) in a 2 × 4 factorial arrangement during 70 days of the experiment. Results showed that a decline in the n‐6 to n‐3 ratio led to a reduction in serum cholesterol concentration (p < 0.05) and an increase in serum HDL content (p < 0.05). Additionally, decreasing n‐6 to n‐3 ratio and increasing clove bud level caused a remarkable decline in serum aspartate aminotransferase (p < 0.05 and p < 0.001) and alanine aminotransferase (p < 0.05 and p < 0.05) enzyme activities. Furthermore, total antioxidant capacity (p < 0.05 and p < 0.001) as well as serum vitamin E concentration (p < 0.05 and p < 0.001) was decreased and enhanced by low n‐6 to n‐3 ratio diets (LRD) and clove bud powder respectively. Decreasing the n‐6 to n‐3 ratio lowered hepatic lipid (p < 0.05) and glycogen contents (p < 0.01) as well as tissue integrity (p < 0.05), and raised liver MDA concentration (p < 0.001), markedly. Nevertheless, increments in clove bud content led to a reduction (p < 0.01) in liver relative weight (p < 0.05) and hepatic fat vacuole numbers. In general, the best synergistic responses on modulating of blood lipids and serum enzyme activities were observed when the highest level of clove bud was supplemented in the diets with low n‐6 to n‐3 ratio. Likewise, antioxidant indices were improved by administration of dietary clove bud powder although feeding fish oil was observed to elevate the susceptibility of blood and hepatocytes to lipid peroxidation.  相似文献   
230.
Postmortem radiographic examinations of animals are commonly performed in judicial investigations to rule out gunshot and fractures. However, there was no available data on radiographic postmortem changes of animals. Forty-one sets of abdominal radiographs of feline cadavers made within 12 h of death were evaluated for postmortem changes. Intravascular gas was detected in 11 of 41 (27%) cadavers. The most common site of intravascular gas was the liver. Intravascular gas was also present in the aorta, femoral artery, celiac and cranial mesenteric arteries, and caudal superficial epigastric artery. Intrasplenic gas was detected in two cadavers. Only two cadavers had distended small intestine. One cadaver had pneumatosis coli. The changes detected were most likely due to putrefaction.  相似文献   
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