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91.
Leptospirosis is a global zoonotic disease that the transmission is driven by complex geographical and temporal variation in demographics, animal hosts and socioecological factors. This results in complex challenges for the identification of high‐risk areas. Spatial and temporal epidemiological tools could be used to support leptospirosis control programs, but the adequacy of its application has not been evaluated. We searched literature in six databases including PubMed, Web of Science, EMBASE, Scopus, SciELO and Zoological Record to systematically review and critically assess the use of spatial and temporal analytical tools for leptospirosis and to provide general framework for its application in future studies. We reviewed 115 articles published between 1930 and October 2018 from 41 different countries. Of these, 65 (56.52%) articles were on human leptospirosis, 39 (33.91%) on animal leptospirosis and 11 (9.5%) used data from both human and animal leptospirosis. Spatial analytical (n = 106) tools were used to describe the distribution of incidence/prevalence at various geographical scales (96.5%) and to explored spatial patterns to detect clustering and hot spots (33%). A total of 51 studies modelled the relationships of various variables on the risk of human (n = 31), animal (n = 17) and both human and animal infection (n = 3). Among those modelling studies, few studies had generated spatially structured models and predictive maps of human (n = 2/31) and animal leptospirosis (n = 1/17). In addition, nine studies applied time‐series analytical tools to predict leptospirosis incidence. Spatial and temporal analytical tools have been greatly utilized to improve our understanding on leptospirosis epidemiology. Yet the quality of the epidemiological data, the selection of covariates and spatial analytical techniques should be carefully considered in future studies to improve usefulness of evidence as tools to support leptospirosis control. A general framework for the application of spatial analytical tools for leptospirosis was proposed.  相似文献   
92.
ABSTRACT

1. The aim of this study was to assess the incidence of pathogens and the development of spoilage microflora in organic chicken meat originating from a small poultry slaughterhouse and stored for 14 days at 2°C aerobically (control) or in one of two modified atmosphere packaging systems (MAP1: 80% O2, 20% CO2 and MAP2: 70% N2, 30% CO2).

2. Campylobacter jejuni survived well during storage; and was found on the skin in 95% of samples (262/276).

3. In general, both the skin and meat samples showed a good initial microbiological quality with total viable counts of less than 3 log cfu/g in meat and approximately 5 log cfu/g on skin.

4. No difference was found between breast and thigh samples during the experiment.

5. Shelf life was limited mainly by the development of mesophilic and psychrotrophic microflora on skin which were found at 7-day storage for the control and MAP1 and 10 days for MAP2.  相似文献   
93.
This study was conducted using 120 multiparous Awassi ewes during the breeding season to compare the effects of using previously used controlled internal drug release (CIDR) on the hormone profiles, reproductive performance and economic measures of ewes. Ewes were randomized to receive one of five previously used CIDR (previously used for 6, 12, 18, 24 or 30 days) or the new CIDR as a control for 6 days (CIDR6, CIDR12, CIDR18, CIDR24, CIDR30, and CIDR0 [control], respectively). Blood samples were collected on four occasions, at the time of CIDR insertion, after 3 days of insertion, and at the time of withdrawal and insemination. Serum estradiol (E2) and progesterone (P4) concentrations were measured. Timed insemination was performed 48 hr post‐CIDR withdrawal. Pregnancy was diagnosed by ultrasonography 23 days after insemination and confirmed on day 35. The heat detection rate was significantly (p < 0.05) higher in the CIDR0 and CIDR6 groups than in the CIDR18 and CIDR30 groups. The total pregnancy rate and fecundity were significantly (p < 0.05) higher in the CIDR6 group than in other groups. P4 level was significantly (p < 0.05) higher in the CIDR0 group than in the CIDR30 group at the time of removal. At each time point, the E2 level was significantly (p < 0.05) higher in the CIDR6 group than at the other groups. The total variable cost, total cost, return and net profit were higher in the CIDR6 and CIDR0 groups than in the other groups. In conclusion, although previously used CIDRs are efficient at synchronizing oestrus in ewes, the duration of previously usage significantly affected the reproductive parameters and economic profit. CIDRs previously used for 6 days and new CIDRs provided the highest fertility and fecundity rates, besides return and net profit. Economically, it is not advisable to use CIDRs that previously used for 12 days or more.  相似文献   
94.
Dormant meristems of fascicles explanted from 10-year-old, field-grown trees of Pinus brutia Ten. were cultured in vitro. Browning of cultured fascicles was reduced by including 150 mg l(-1) sodium diethyldithiocarbamate (SDD) in a cytokinin-containing medium. The stage of development of fascicles when placed in culture affected both shoot-bud production and the degree of browning. Only fascicles at an advanced stage of development had a high rate of shoot-bud production. Fascicles cultured for 6 weeks in initiation medium containing 150 mg l(-1) SDD and then for 4 weeks in initiation medium containing 1 mg l(-1) insoluble polyvinylpolypyrrolidone showed the highest rate (23%) of shoot-bud development and the lowest rate (15%) of browning. Elongation of activated shoot buds was considerably enhanced by reducing the concentration of cytokinin in the culture medium. Only shoots >/= 20 mm in height were capable of producing further crops of buds and shoots. When treated with a combination of auxin and cytokinin, only 16% of the elongated shoots produced roots.  相似文献   
95.
Objective To develop a simple and effective surgical technique for third‐compartment cannulation in alpacas. Design Prospective study using six adult male alpacas. Methods General anaesthesia was induced and a polyurethane gastrostomy tube was surgically implanted into the distal portion of the third compartment. Results Three of the alpacas retained their cannulas for a 100‐day period; however, three cannulas were dislodged during the study. Two of the three dislodged cannulas were replaced during a second surgical procedure. Cannulas were well tolerated by the alpacas and all animals remained clinically healthy during the study period. Third compartment contents did not leak from the cannulation site. The tubes were manually removed following the completion of the study and the small defect in the body wall quickly healed over in all animals. Conclusion Surgical placement of polyurethane tubes designed for percutaneous endoscopic gastrostomy is a useful method of cannulating the third compartment in camelids. This technique can be used for experimental studies and possibly could be used for nutritional support and fluid therapy in sick camelids that might need long‐term care.  相似文献   
96.
The effect of using crushed Nigella sativa seeds (NSS) as a natural growth promoter instead of the antibiotic growth promoter bacitracin methylene disalicylate (BMD) in broiler rations that contain one of two types of anticoccidials (either lasalocid Na or 3-nitro) on growth performance, blood constituents and some selected antibody titers was studied. An experiment was conducted on five dietary groups with two different growth promoter's supplementation from one to 42 days of age. The statistical findings of this experiment prove that replacing BMD by crushed NSS significantly improve growth performance. The serum levels of cholesterol, triglyceride were significantly decreased, while, high density lipoprotein (HDL) was significantly increased. Concerning the findings that pertain to immunity, antibody titer against Newcastle and infectious bursal diseases were significantly improved by replacing BMD by crushed NSS, but no significant effects were noticed in antibody titer against infectious bronchitis. In conclusion, from the results of the current study it could be speculated that crushed NSS could be of value to replace BMD in broiler diets. Further studies must be performed to detect the proper level of NSS before field application.  相似文献   
97.
1. The effects of a mixture of 12 Lactobacillus strains (LC) on the growth performance, abdominal fat deposition, serum lipids and weight of organs of broiler chickens were studied from 1 to 42 d of age. 2. One hundred and thirty-six 1-d-old male broiler chicks were assigned at random to two dietary treatments: a basal diet (control), and a basal diet with 0.1% LC. 3. The supplementation of LC in broiler diets improved the body weight gain and feed conversion rate from 1 to 42 d of age and was effective in reducing abdominal fat deposition but only after 28 d of age. 4. The LC diets reduced serum total cholesterol, low density lipoprotein (LDL) cholesterol and triglycerides in broilers from 21 to 42 d of age. However, there was no significant difference in serum high density lipoprotein (HDL) cholesterol between control and LC-fed broilers. There was also no significant difference in the weights of organs of control and LC-fed broilers. 5. The results indicated that the mixture of 12 Lactobacillus strains have a hypolipidaemic effect on broilers.  相似文献   
98.
AIM: To study the molecular mechanism of Chinese medicine formula Bushen Bugu Tang (BSBGT) for the treatment of postmenopausal osteoporosis (PMO). METHODS: Forty female SD rats were divided into four groups: the sham group, OVX group, estrogen treatment group and BSBGT treatment group, ten for each, difference operation and treatment were given. Subsequently, bone mineral density (BMD), bone histomorphometric changes and collagen type I expression in the femur of these rats were examined. In order to position the target of the formula acting on bone, the effect of BSBGT on regulation of mRNA levels of RANKL and OPG, two key factors for regulating osteoclastogenesis, by using rat calvarial-derived stromal cell cultrues, was elucidated. RESULTS: The BSBGT formula was found as effective as estrogen in preventing the reduction of BMD, the trabecular area and trabecular numbers in femora and also the decrease in collagen type I expression following ovariectomy. RT-PCR resulted showed that both estrogen and BSBGT significantly up-regulated OPG mRNA level and down-regulated RANKL mRNA level, resulting in an increased ratio of OPG/RANKL in cultured rat stromal cells. CONCLUSIONS: The ratio of OPG/RANKL within the osseous environment determines whether bone formation predominates bone resorption. We therefore concluded that the BSBGT formula might be as effective as estrogen in prevention of postmenopausal osteoporosis through the mechanism of up-regulating RANKL expression and down-regulating OPG expression in osteoblast/stromal cells.  相似文献   
99.
Precision Agriculture - Poor land leveling of paddy fields leads to irrigation problems which affect crop establishment and ultimately yield. One way to manage this is to vary the seeding rate...  相似文献   
100.
Journal of Crop Science and Biotechnology - Flash flood causes a serious damage to rice crops in northern and eastern parts of Bangladesh almost every year. This study was designed to identify...  相似文献   
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