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31.

Cattle production is the major livestock production activity and the mainstay of Namibia’s economy. Sustained beef exports are contingent on a sound sanitary environment where diseases such as brucellosis are under control. In this retrospective study, 49,718 bovine brucellosis testing results from 2004 to 2018 were analyzed to determine the proportion of sero-positive cattle and herds, and the spatial distribution of positive reactors from commercial and communal areas. In total, 244 positive reactors were identified based on the Rose Bengal Test (RBT) and the Complement Fixation Test (CFT) in series, giving an overall proportion of infected animals of 0.49% (244/49,718; 95% CI, 0.43–0.56%) and an overall proportion of infected herds of 9.26% (78/842; 95% CI, 7.49–11.41%). There was a higher proportion of sero-positive communal herds (33.09%) and cattle (10.27%) than commercial herds (4.67%) and cattle (0.24%; p < 0.05). Annually, the proportion of positive reactors was 0–1.37% in the commercial area and 0–52.38% in the communal areas, with a clear decline in positive reactors in the communal areas. Within the commercial sector, the proportion of positive reactor dairy, beef, and export cattle was 0.19% (51/27,067; 95% CI, 0.14–0.25%), 0.30% (48/16,098; 95% CI, 0.22–0.40%), and 0.33% (16/4811; 95% CI, 0.20–0.54%), respectively. Abortions were found to be the major reason for Brucella testing in the communal areas. About 12.65% (96/759) of abortion-linked sera tested positive in the communal areas, but none were positive in beef or dairy cattle. Widespread vaccination of cattle and robust planned surveillance is recommended to reduce the incidence of the disease, its associated production losses and public health risk.

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Tropical Animal Health and Production - This study retrospectively investigated the effect of breed and season on the lambing/kidding dynamics, growth performance, neonatal viability, and weaning...  相似文献   
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OBJECTIVE: To identify risk factors for development of excessive tibial plateau angle (TPA) in large-breed dogs with cranial cruciate ligament disease (CCLD). DESIGN: Case-control study. ANIMALS: 58 dogs with excessive TPAs (ie, TPA >or= 35 degrees ; case dogs) and 58 dogs with normal TPAs (ie, TPA or= 35 degrees in both limbs were 13.6 times (95% confidence interval, 2.72 to 68.1) as likely to have been neutered before 6 months of age as were control dogs with TPA 相似文献   
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Michael SF  Templeton CN  Greene E 《Science (New York, N.Y.)》2005,310(5748):620-1; author reply 620-1
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This paper describes a screening method for antioxidant potential determination based on luminol/hemin/hydrogen peroxide chemiluminescence. The emission depletion, caused by an antiradical compound added during the chemiluminescence decay, is proportional to the number of reactive species trapped. Therefore, the difference between the areas of the emission decay curves, obtained in the absence and in the presence of the potential antioxidant, is a measure for the antiradical capacity of the sample. The technique has been applied to measure the antiradical capacity of pure compounds and complex mixtures from natural origin, providing reliable results that indicate the method's feasibility.  相似文献   
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An experiment evaluating three fertilizer types (granular, liquid, and controlled released fertilizer) with nitrate ranging from 0% to 44% was conducted over two seasons on southern highbush blueberry ‘Star’ at the University of Georgia’s blueberry farm in Alapaha, GA. The objective was to identify the effect on fruit quality, plant growth, and plant tissue nitrogen status. This work demonstrated that the applications of fertilizer had similar effects on fruit quality and growth for ‘Star’ grown in sandy organic soils. In addition, fertilizers with 36.5% or 44% nitrate did not appear to have significant accumulation of nitrate in the leaves. Soil analysis revealed that none of the fertilized soils significantly increased cation exchange capacity; however, soil pH increased in soils with 36.5% and 44% nitrate applications. This suggests these nitrate levels will require continued soil monitoring and possible soil acidification to maintain appropriate soil pH for blueberry production (4.0–5.5 pH).  相似文献   
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The ABCB gene subfamily of ABC (ATP-binding cassette) transporters is responsible for transporting a wide spectrum of molecules including peptides, iron, bile salts, drugs, and phospholipids. In humans, ABCB4 appears to be exclusively expressed on the apical membrane of hepatocytes where it translocates phosphatidylcholine from the inner to the outer leaflet of the canalicular membrane. Functional alterations in the ABCB4 transporter are associated with a number of cholestatic syndromes in humans. Because of its role in biliary lipid homeostasis in humans, investigation of the ABCB4 gene in dogs is warranted. Thus, the full cDNA sequence of canine ABCB4 was elucidated and its mRNA and protein expression levels in tissues were determined. Canine ABCB4 consists of 3804 nucleotides spanning 26 exons and is 89% identical to human ABCB4. Expression of ABCB4 in canine liver supports a potential role for the protein in normal biliary function similar to that in humans. The function of ABCB4 expressed in brain tissue has yet to be determined.  相似文献   
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Tropical Animal Health and Production - Trichinellosis is a worldwide zoonosis with genotypes affecting different domestic and wild animals and is widely distributed throughout the world. Species...  相似文献   
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