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1.
Disease clusters were retrospectively explored at national level using a geo-referenced dataset from the 2001 Uruguayan Foot-and-Mouth Disease (FMD) epidemic. Disease location and time (first 11 epidemic weeks) were analysed across 250 counties (of which 160 were infected), without and with control for human mobility related factors (human population and road densities). The null hypothesis of random disease distribution over space and/or time was assessed with: (i) purely temporal; (ii) purely spatial; and (iii) space/time tests. At least within epidemic weeks 2 and 6, a principal disease cluster was observed in 33 contiguous counties (P < 0.01). Two secondary clusters, located at >100 km from each other, were also observed (P < 0.01). The purely spatial test that controlled for human population density identified two non-contiguous clusters (P < 0.01). Space and time analysis also revealed the same 33 counties as members of the principal cluster, of which 31 were also clustered when human population was controlled (P < 0.01). No clusters were reported by the spatial test when road density was assessed. The hypothesis that human mobility related factors autocorrelate with disease was empirically supported by two pieces of information: (i) removal of human population/road densities eliminated >93.9% of the counties included in the principal disease cluster; and (ii) statistically significant correlations (P < 0.05) were observed in the first three epidemic weeks between road density and the number of cases. Clusters where human population density was associated with 47% greater number of cases/sq. km than that of the principal cluster indicated possible roles as disease vectors (vector clusters). Selective control policy in vector clusters is recommended. Periodic (i.e. weekly) cluster and correlation analyses of both disease and other covariates may facilitate disease surveillance and help design space-specific control policy.  相似文献   

2.
Geo‐referenced data from the 2001 Uruguayan foot‐and‐mouth disease (FMD) epidemic were explored to assess whether spatial analysis could lead to cost‐benefit based policies. Four variables were analysed: (i) location and size of 4022 individual rural land parcels, of which 574 were infected over 60 days, (ii) animal density, (iii) percentage of dairy farms per county, and (iv) road density. Each variable was categorized into two to five classes (e.g. small/medium/large) and the proportion of cases per class reported at days 1–3 of the epidemic was compared with that reported at days 4–6. A higher proportion of cases was found at days 4–6 than at days 1–3 in areas with: small and medium size land parcels, high animal density, >20% farms specialized in dairy production, and high road density (P < 0.03 for each). Each of these classes showed a greater proportion of cases at days 7–60 than the proportion of the total territory covered by each class's area (early case concentration ratios: 1.14–1.37). Land parcel clusters were indicated by Moran's I‐test (P < 0.01). A new region was constructed by intersecting the four spatial classes associated with higher proportions of cases at days 4–6. At days 7–60, this region included 50.4% of all cases and represented 30.6% of the territory under study (final case concentration ratio: 1.65). The final area per case in this region was at least 33% lower and covered at least 45% less territory than any of the four single‐variable approaches. Bio‐statistical, multivariate spatial analysis of early cases may greatly increase the efficiency of epidemiologic policy.  相似文献   

3.
Vascular endothelial growth factor (VEGF) and metalloproteinase (MMP) 2 and 9 are useful biomarkers in human lymphoma. During cancerogenesis, transforming growth factor beta (TGF‐β) stimulates VEGF and MMPs production. VEGF and TGF‐β plasma levels were tested by ELISA, MMP‐2 and MMP‐9 by gelatine zymography in 37 dogs with lymphoma, 13 of which were also monitored during chemotherapy. Ten healthy dogs served as control. Lymphoma dogs showed higher act‐MMP‐9 (P < 0.01) and VEGF (P < 0.05), and lower TGF‐β than controls, and a positive correlation between act‐MMP‐9 and VEGF (P < 0.001). Act‐MMP‐9 and VEGF were significantly higher in T‐cell lymphomas, and in stage V compared with stages III–IV disease, regardless of immunophenotype. VEGF was higher in high‐grade compared with low‐grade T‐cell lymphomas. No correlation was found between cytokines levels at presentation and outcome. During chemotherapy, act‐MMP‐9 and VEGF decreased in B‐cell lymphomas (P < 0.01), suggesting a possible predictive role in this group of dogs.  相似文献   

4.
Twenty‐four Chinese Holstein growing steers were randomly divided into three groups and fed a diet containing 0 (the control group), 15 (treatment I group, or TG1) or 25 (treatment II group, or TG2) g/day 2‐hydroxy‐4‐(methylthio) butanoic acid isopropyl ester (HMBi). Compared with the control group, the final body weights, total gains and average daily gains in the treatment groups increased (P < 0.01). The concentration of total protein (TP) for TG1 increased (P < 0.01). The levels of albumin in TG1 were higher than those in TG2 and the control group (P < 0.05). The concentration of alanine aminotransferase (ALT) in TG2 increased (P < 0.05), but concentrations of aspartate aminotransferase (AST) in the treatment groups decreased (P < 0.05). HMBi improved the concentrations of selenium in both TG1 (P < 0.05) and TG2 (P < 0.01). The levels of glutathion peroxidase (GSH‐Px) in TG2 were higher than those of the control group (P < 0.05). Moreover, HMBi increased the concentrations of growth hormone (GH) in both TG1 (P < 0.05) and TG2 (P < 0.01). These results indicate that the addition of HMBi increases growth performance, serum concentrations of GH and AST; 15 g/day HMBi increases concentrations of total protein and albumin, and 25 g/day HMBi increases concentrations of ALT and GSH‐Px.  相似文献   

5.
We investigated 10 suckling cross‐bred calves (Japanese Black (Wagyu) × Holstein) and collected data on the physiological stress responses of the young calves to long‐haul road transportation. All calves were male and 21–47 days of age. The calves were obtained at a livestock market and were transported from the market to the university in a commercial livestock vehicle. The total haul distance and time were 306.9 km and 7 h, respectively. The calves were deprived of food and water during transportation. Blood samples, electrocardiograms, and rectal temperatures were collected immediately after transportation and after one week of habituation at the university. Serum pH was significantly lower (P < 0.01), while serum triiodothyronine, aspartate aminotransferase, non‐esterified fatty acids (all P < 0.05), and heart rate (P < 0.01) were significantly higher immediately after transportation. The concentrations of blood lactic acid (P = 0.08) and serum alanine aminotransferase (P = 0.06) tended to be higher after transportation. These physiological responses suggest that the stress caused by long‐haul transportation causes significant effects on liver function in young calves.  相似文献   

6.
Two hundred and forty 1‐day‐old male Arbor Acres broiler chickens were randomly assigned to five dietary treatments with six replicates of eight chickens per replicate cage for a 42‐day feeding trial. Broiler chickens were fed a basal diet supplemented with 0 (control), 250, 500, 750 or 1000 mg/kg betaine, respectively. Growth performance was not affected by betaine. Incremental levels of betaine decreased the absolute and relative weight of abdominal fat (linear P < 0.05, quadratic P < 0.01), low‐density lipoprotein cholesterol (LDL‐C), triglyceride (TG) and total cholesterol (TC) (linear P < 0.05), and increased concentration of nonesterified fatty acid (NEFA) (linear P = 0.038, quadratic P = 0.003) in serum of broilers. Moreover, incremental levels of betaine increased linearly (P < 0.05) the proliferator‐activated receptor alpha (PPARα), the carnitine palmitoyl transferase‐I (CPT‐I) and 3‐hydroxyacyl‐coenzyme A dehydrogenase (HADH) messenger RNA (mRNA) expression, but decreased linearly (P < 0.05) the fatty acid synthase (FAS) and 3‐hydroxyl‐3‐methylglutaryl‐CoA (HMGR) mRNA expression in liver of broilers. In conclusion, this study indicated that betaine supplementation did not affect growth performance of broilers, but was effective in reducing abdominal fat deposition in a dose‐dependent manner, which was probably caused by combinations of a decrease in fatty acid synthesis and an increase in β‐oxidation.  相似文献   

7.
In order to investigate the effect of dietary soybean phospholipid supplement on hepatic and serum indexes relevant to fatty liver hemorrhagic syndrome (FLHS) in layers, 135 300‐day‐old Hyline Brown layers were randomly divided into three groups (control, pathology and prevention), and each group had 45 layers with three replicates. Birds in the three groups were respectively fed the control diet, high‐energy low‐protein diet and high‐energy high‐protein diet affixed with 3% soybean phospholipid instead of maize. Results showed in the 30th day, birds’ livers in the pathology group became yellowish, enlarged in size and had hemorrhagic spots, while the prevention and control groups’ layers did not have such pathological changes. Contents of triglyceride, total cholesterol, low‐density lipoprotein – cholesterol, non‐esterified fatty acid and malondialdehyde in serum or liver homogenate in prevention and control groups were remarkably lower than those in the pathology group (P < 0.05 or P < 0.01), as with the activities of glutamic oxalacetic transaminase and glutamic‐pyruvic transaminase (P < 0.01); high‐density lipoprotein – cholesterol value was strikingly higher than that of the pathology group (P < 0.01). It is suggested dietary soybean phospholipids supplement may effectively improve hepatic and blood indexes relevant to FLHS, which provides a new point for preventing FLHS occurrence rate in laying flocks and treating human non‐alcohol fatty liver disease.  相似文献   

8.
The effects of the administration of four Lactobacillus strains as probiotics on the constitution of microbial populations in the intestine of pigs were investigated by using a litter of pigs. The experimental group was fed a diet blended with the freeze‐dried powder containing lactobacilli at a concentration of 0.2% (W/W). After 4 weeks of probiotics administration, the total viable count of anaerobes in the feces was not significantly different between the pigs fed a diet supplemented with probiotics and the pigs given the non‐supplemented diet. However, viable counts of eubacteria were significantly higher (P < 0.01) in the feces of pigs fed a diet supplemented with probiotics than in the pigs given the non‐supplemented diet. Conversely, viable counts of clostridia were significantly lower (P < 0.01) in the feces of pigs fed a diet supplemented with probiotics than the pigs given the non‐supplemented diet. The total volatile fatty acid concentrations in the feces of pigs that were given a diet supplemented with probiotics were significantly lower (P < 0.05) than those given the non‐supplemented diet. Further, the molar proportion of n‐butyric acids in the feces of pigs that were given a diet supplemented with probiotics, was significantly lower (P < 0.05) than those given the non‐supplemented diet.  相似文献   

9.
10.
Five hundred and twenty‐eight newly weaned pigs were given four treatments, with eight replicates per treatment. Sixteen to 18 pigs were assigned per replicate and were fed diets supplemented with 0 or 3% medium‐chain triglyceride (MCT) and 0 or 40 ppm colistin sulfate (CS) in a 2 × 2 factorial arrangement for 2 weeks. The results showed that dietary supplementation with MCT improved the gain‐to‐feed ratio during days 3‐7 and in the overall period (P < 0.05). Dietary supplementation with MCT decreased coliforms counts (C) in colon and rectum content (P < 0.05). Dietary supplementation with CS decreased C and lactic acid bacteria plus C counts (L + C) in cecum (P < 0.05), and C, L + C (P < 0.01) and ratio of L and C (P < 0.05) in colon and rectum contents. The lack of interactions between MCT and CS indicates different modes of action and additive effects between the two supplementations. In conclusion, supplementation with MCT in diet with or without CS could improve the intestinal microbial environment and the feed utilization efficiency of newly weaned pigs.  相似文献   

11.
This study evaluated the differences of physico‐chemical and nutritional qualities between abnormal colored chicken livers (ANCCLs) and normal colored chicken livers (NCCLs) and the safety of the both livers. Compared with NCCLs, ANCCLs were lower in protein, water contents (P < 0.01), pH and pigment contents (P < 0.05). NCCLs contained higher polyunsaturated fatty acid (PUFA) and saturated fatty acids (SFA) (P < 0.05). The PUFA/SFA ratio of NCCLs was 0.453, higher (P < 0.05) than that of ANCCLs. The contents of alanine, valine, tyrosine, lysine and histidine in NCCLs were higher (P < 0.05) than in ANCCLs. The contents of K, Na, P, Cu, Fe and Se of NCCLs were higher (P < 0.05), but the Ca content was lower (P < 0.05). The content of the heavy metals (As, Hg, Pb and Cd) of the two types of livers complied with food safety requirements. Although NCCLs had higher nutritional value than ANCCLs, both livers were acceptable for human consumption.  相似文献   

12.
Insulin‐independent actions of glucagon‐like peptide‐1 (GLP‐1) are not yet clear in ruminants. Four Suffolk mature wethers (60.0 ± 6.7 kg body weight (BW)) were intravenously infused with insulin (0.5 mU/kg BW/min; from 0 to 90 min) and GLP‐1 (0.5 μg/kg BW/min; from 60 to 150 min) with both hormones co‐administered from 60 to 90 min, in a repeated‐measure design under euglycemic clamp for 150 min, to investigate whether GLP‐1 has insulin‐independent actions. Jugular blood samples were taken at 15‐min intervals for plasma hormones and metabolites analysis. Compared to baseline concentrations (at 0 min), insulin infusion decreased (P < 0.05) plasma concentrations of glucagon, non‐esterified fatty acids (NEFA), lactate, nonessential amino acids (NEAA), branched‐chain amino acids (BCAA), total amino acids (TAA) and urea nitrogen (UN). Insulin plus GLP‐1 infusion induced a greater increase (P < 0.05) in plasma concentrations of insulin and triglyceride (TG), but decreased (P < 0.05) glucagon, total cholesterol (T‐Cho), NEAA and UN plasma concentrations. GLP‐1 infusion increased (P < 0.05) NEFA, β‐hydroxybutyrate and TG, but decreased (P < 0.05) glucagon, T‐Cho, NEAA, BCAA and UN plasma concentrations. In conclusion, GLP‐1 exerts extrapancreatic roles in ruminants not only insulin‐independent but probably, in contrast to non‐ruminants, antagonistic to insulin effects.  相似文献   

13.
To investigate the role of polysaccharide from Acanthopanax senticosus (ASPS) on lipopolysaccharide (LPS)‐induced intestinal injury, mice in three treatments were administrated orally with or without ASPS (300 mg/kg body weight) for 14 days, followed by challenge with LPS or saline. At 4 h post‐injection, blood and intestinal samples of six mice / treatment were collected. The results showed ASPS ameliorated LPS‐induced intestinal morphological deterioration, proven by improved villus height (P < 0.05) and villus height : crypt depth ratio (P < 0.05). ASPS also elevated the mucosal barrier of LPS‐challenged mice, supported by reduced plasma diamine oxidase (DAO) activity (P < 0.05) and L‐lactate (P < 0.05), increased mucosal DAO activity (P < 0.05) as well as enhanced intestinal tight junction proteins expression involving occludin‐1 (P < 0.05) and zonula occludens‐1 (P < 0.05). In addition, ASPS decreased LPS‐induced secretion of inflammatory mediators, including tumor necrosis factor (TNF)‐α (P < 0.05) and prostaglandin E2 (P < 0.05). Also, ASPS down‐regulated messenger RNA expression of toll‐like receptor 4 (TLR4) and its downstream signals, including myeloid differentiation factor 88 (P < 0.05), TNF‐α receptor‐associated factor 6 (P < 0.05), as well as nuclear factor (NF)‐κB p65 (P < 0.05) and its protein expression. These findings suggest that ASPS improves intestinal integrity under inflammation conditions connected with inhibiting TLR4/NF‐κB signaling pathways.  相似文献   

14.
We describe multiple‐aetiology infections involving non‐O157 Shiga toxin‐producing Escherichia coli (STEC) identified through laboratory‐based surveillance in nine FoodNet sites from 2001 to 2010. A multiple‐aetiology infection (MEI) was defined as isolation of non‐O157 STEC and laboratory evidence of any of the other nine pathogens under surveillance or isolation of >1 non‐O157 STEC serogroup from the same person within a 7‐day period. We compared exposures of patients with MEI during 2001–2010 with those of patients with single‐aetiology non‐O157 STEC infections (SEI) during 2008–2009 and with those of the FoodNet population from a survey conducted during 2006–2007. In total, 1870 non‐O157 STEC infections were reported; 68 (3.6%) were MEI; 60 included pathogens other than non‐O157 STEC; and eight involved >1 serogroup of non‐O157 STEC. Of the 68 MEI, 21 (31%) were part of six outbreaks. STEC O111 was isolated in 44% of all MEI. Of patients with MEI, 50% had contact with farm animals compared with 29% (< 0.01) of persons with SEI; this difference was driven by infections involving STEC O111. More patients with non‐outbreak‐associated MEI reported drinking well water (62%) than respondents in a population survey (19%) (< 0.01). Drinking well water and having contact with animals may be important exposures for MEI, especially those involving STEC O111.  相似文献   

15.
To clarify muscle type‐specific effect of myostatin on myogenic regulatory factors (MRFs), we examined mRNA expression of MRFs in five skeletal muscles of normal (NM) and myostatin‐deficient double‐muscled (DM) adult Japanese Shorthorn cattle by quantitative reverse‐transcribed PCR. Among the four MRFs, namely, Myf5, MyoD, myogenin, and MRF4, MyoD expression was different among the muscles of the DM cattle (P < 0.01) but not of the NM cattle. Meanwhile, MyoD expression was significantly elevated only in masseter (MS) muscle in the DM cattle due to the myostatin deficiency (P < 0.05). Myf5 and MRF4 expression in semitendinosus (ST) was higher in the DM than in the NM cattle (P < 0.05). According to analysis of myosin heavy chain (MyHC) isoform expression, more MyHC‐2x and ‐2a and less ‐slow isoforms were expressed in the longissimus and ST muscles compared to the MS muscle in both cattle (P < 0.05), but no significant difference in MyHC expression was observed between the NM and DM cattle. Taken together, myostatin has influences on Myf5 and MRF4 expression in faster‐type muscles and on MyoD expression in slower‐type muscles, suggesting a possible muscle type‐specific effect of myostatin in skeletal muscle growth and maintenance.  相似文献   

16.
Rodent pest population outbreaks occur frequently in grassland ecosystems in northern China. The Mongolian gerbil (Meriones unguiculatus) is a dominant pest rodent which is distributed across the semi‐desert grasslands of Inner Mongolia, China. In 2009, we studied the contraceptive effect of levonorgestrel‐quinestrol (EP‐1), concentration 50 ppm, on a wild Mongolian gerbil population. The one‐off contraceptive treatment was compared with a control group using a semi‐monthly live trapping method in the Ordos Semi‐desert Grassland Region of Inner Mongolia. The results show that juveniles were not recruited in spring in the treatment group. Ratios of juveniles in the control and treatment groups showed significant semi‐monthly differences from spring to summer (one‐way ANOVA, F2, 14= 7.53, P < 0.05). Between both groups, annual fluctuations of juvenile and total population densities were significantly different respectively (F2, 14= 4.64, P < 0.05; F2, 18= 7.72, P < 0.05). The contraceptive EP‐1 delayed the normal reproductive pattern of Mongolian gerbil populations. This suppressed birth rates of gerbil populations, reduced their densities, and changed their age structures. The period of EP‐1 baiting should be extended but it could be an ideal method for controlling Mongolian gerbil populations during each breeding season.  相似文献   

17.
A total of 64 5‐month‐old Pietrain pigs were randomly allocated to four treatments with four replicates per treatment according to body weight. The pigs were fed either a standard corn‐soybean meal based control diet (treatments 1 and 2), the standard diet with 1% Lycium barbarum (LB) (treatment 3), or the standard diet with 1% Polygala tenuifolia Willd (PT) (treatment 4). Serum lactic acid and glucose concentrations were increased in stressed pigs (P < 0.05). Addition of the herbs in the diet had no effect on the serum lactic acid concentration, but 1% LB decreased (P < 0.05) serum glucose concentration in the stressed pigs. Pre‐slaughter stress also decreased (P < 0.01) liver glycogen concentration and the decrease could be inhibited by addition of 1% LB in the diet (P > 0.05). Pre‐slaughter stress increased the concentration of maleic dialdehyde (MDA) (P < 0.05) and decreased glutathione peroxidase (GSH‐Px) activity in serum, while dietary 1% LB increased (P < 0.05) the activity of GSH‐Px and decreased the concentration of MDA in the serum. In conclusion, pre‐slaughter stress induces oxidative stress in pigs and dietary supplementation with 1% LB improves antioxidant capacity in stressed pigs before slaughtering.  相似文献   

18.
Transitional cell carcinoma (TCC) is a urinary bladder tumour associated with high mortality in dogs. In this study, we investigated the feasibility of using p63, Ki67 or β‐catenin as a clinical marker for predicting biological behaviour and prognosis in canine TCC. Expression levels of these proteins in TCC (n = 25), polypoid cystitis (n = 5) and normal urinary bladder (n = 5) were scored after immunohistochemical staining. The staining scores for p63 (P < 0.01) and β‐catenin (P < 0.05) in TCC were significantly lower than those in normal urinary bladder and polypoid cystitis. In contrast, Ki67 (P < 0.01) staining scores in TCC were significantly higher than those in normal urinary bladder and polypoid cystitis. In TCC, low p63 expression was significantly related to the presence of vessel invasion (P < 0.05) and metastasis (P < 0.01) as well as short survival time (P < 0.05). These findings show that p63 could be a reliable marker for predicting prognosis in canine TCC.  相似文献   

19.
To investigate effects of Aspergillus oryzae culture (AOC) and 2‐hydroxy‐4‐(methylthio) butanoic acid (HMB) on milk performance and rumen fermentation of dairy cows. Sixty‐four multiparous Chinese Holstein cows were randomly allocated into four experimental diets: (i) Control diet; (ii) AOC diet: 5 g AOC/day per head; (iii) HMB diet: 25 g HMB/day; and (iv) AH diet: 5 g AOC plus 25 g HMB/day. Added HMB tended to increase the yield of milk protein (P = 0.06) and 3.5% fat‐corrected milk (P = 0.08) and milk fat content (P = 0.09). Milk fat yield (P = 0.03) and the contents of milk protein (P = 0.05) were increased by adding HMB. The cows fed on AOC diet had a tendency for higher body weight (BW) gain (P = 0.08). Addition of AOC, HMB and AH increased content of microbial protein (MCP) and total volatile fatty acids (VFA) (P < 0.01) in rumen fluid. Populations of rumen fungi, Fibrobacter succinogenes and Ruminococcus flavefaciens relative to total bacterial 16S rDNA (P ≤ 0.03) and activity of carboxymethylcellulase (CMCase) (P < 0.01) were increased with added AOC or HMB. It is inferred that added AOC or HMB can increase the contents of MCP and total VFA potentially by stimulating rumen microbe populations and CMCase activity.  相似文献   

20.
α‐Ketoglutarate (AKG) is an extensively used dietary supplement in human and animal nutrition. The aim of the present study was to investigate effects of dietary AKG supplementation on the energy status and anti‐oxidative capacity in liver and intestinal mucosa of Cherry Valley ducks. A total of 80 1‐day‐old ducks were randomly assigned into four groups, in which ducks were fed basal diets supplemented with 0% (control), 0.5%, 1.0% and 1.5% AKG, respectively. Graded doses of AKG supplementation linearly decreased the ratio of adenosine monophosphate (AMP) to adenosine triphosphate (ATP) in the liver, but increased ATP content and adenylate energy charge (AEC) in a quadratic and linear manner, respectively (< 0.05). Increasing dietary AKG supplemental levels produced linear positive responses in ATP content and AEC, and negative responses in AMP concentration, the ratio of AMP to ATP and total adenine nucleotide in the ileal mucosa (P < 0.05). All levels of dietary AKG reduced the production of jejunal hydrogen peroxide and hepatic malondialdehyde (P < 0.05). Hepatic and ileal messenger RNA expression of AMP kinase α‐1 and hypoxia‐inducible factor‐1α were linearly up‐regulated as dietary AKG supplemental levels increased (P < 0.05). In conclusion, dietary AKG supplementation linearly or quadratically enhanced hepatic and intestinal energy storage and anti‐oxidative capacity of Cherry Valley ducks.  相似文献   

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