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The aim of this study was to identify possible effects of different vaccination strategies (concomitantly or not) against brucellosis and clostridia on intake, performance, feeding behavior, blood parameters, and immune responses of dairy heifers calves. Fifty heifers calves were enrolled [38 Gyr (Zebu, Bos taurus indicus) and 12 5/8 Holstein Gyr]. At 120 d of age, animals were randomly distributed among 3 groups: B (n = 18), vaccinated against brucellosis; C (n = 14), vaccinated against clostridia and CB (n = 18), vaccinated concomitantly for both. Rectal and thermographic temperatures were evaluated on days 1, 0, 1, 2, 3, 5, 7,10, 14, and 28 relatives to the vaccination day. Feed and water intake, body weight (BW), and feeding behavior were monitored daily by an electronic feeding system. Blood was sampled on days 0, 3, 7, 14, and 28, relative to the vaccination day for determination of glucose and -hydroxybutyrate (BHBA) concentrations. Blood sampled on day 0 (prevaccination) and on days 28 and 42 were used to evaluate the immune response against Brucella abortus and clostridia. There was an increase in rectal temperature between the first and the third day postvaccination in the 3 groups. The thermography revealed an increase of local temperature for 7 d on groups B and CB. Group C had increased local temperature for a longer period, lasting for up to 14 d. Dry mater intake was reduced for groups B and CB, but no alteration was observed for group C. No alterations regarding initial BW, final BW, average daily weight gain, and feed efficiency were observed. No differences were observed for the 3 vaccination groups for blood parameters throughout the evaluation period. The concomitant vaccination against brucellosis and clostridia led to lower neutralizing antibody titers against epsilon toxin of Clostridium perfringens and botulinum toxin type C of C. botulinum (C > CB > B). When cellular proliferation assay and serological tests to B. abortus were evaluated, no differences were observed between groups B and CB. The present results indicate that the concomitant vaccination against brucellosis and clostridia has no relevant impact on the intake, performance, and feeding behavior of dairy calves. However, the concomitant vaccination of vaccines against these 2 pathogens impacts animal immunity against clostridial infections.  相似文献   
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ABSTRACT Three field experiments were conducted in 1997, 1998, and 1999 to investigate the effects of angular leaf spot and rust, separately or combined, on host growth and yield of individual bean plants (Phaseolus vulgaris). In each experiment, three treatments were established by inoculating cv. Carioca with Phaeoisariopsis griseola, Uromyces appendiculatus, or with both pathogens. An additional control treatment was not inoculated, but was sprayed with a fungicide. In the 1997 and 1999 experiments, angular leaf spot reached higher disease levels than rust, whereas in 1998, rust was more severe than angular leaf spot. Host growth, expressed as healthy leaf area duration (HAD), and yield were the highest in 1997 and lowest in 1998. In each experiment, the treatments did not differ significantly to the area under leaf area progress curve, HAD, and healthy leaf area absorption (HAA). All inoculated treatments had significantly more severe disease and less yield than the control treatment. Based on the analysis of 60 plants in each experiment, yield was not related to the areas under disease progress curve for either or both diseases. In 1997 and 1999, yield was related to HAD (R(2) = 0.57 and 0.43) and HAA(R(2) = 0.60 and 0.55). Based on the combined analysis of all 36 plots, angular leaf spot reduced the leaf area because of defoliation, whereas rust did not affect the leaf area. Rust reduced yield more than four times that of angular leaf spot, although the decrease in photosynthesis to angular leaf spot was twice that of rust.  相似文献   
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New concepts in phytopathometry continue to emerge, such as the evolution of the concept of pathogen intensity versus the well-established concept of disease intensity. The concept of pathogen severity, defined as the quantitative measurement of the amount of pathogen per sampling unit has also emerged in response to the now commonplace development of quantitative molecular detection tools. Although the concept of disease severity, i.e., the amount of disease per sampling unit, is a well-established concept, the accuracy and precision of visual estimates of disease severity is often questioned. This article will review disease assessment concepts, as well as the methods and assessment aides currently available to improve the accuracy and precision of visually-based disease severity data. The accuracy and precision of visual disease severity assessments can be improved by quantitatively measuring and comparing the accuracy and precision of rates and/or assessment methods using linear regression, by using computer-based disease assessment training programmes, and by developing and using diagrammatic keys (standard area diagrams).  相似文献   
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New Forests - During seed development, plant hormones are involved in processes such as the accumulation of reserves, cellular activity and physiological responses. The present study aimed to...  相似文献   
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The present study was designed to verify whether frutalin (FTL) affords gastroprotection against the ethanol-induced gastric damage and to examine the underlying mechanism(s). Gastric damage was induced by intragastric administration of 0.2 ml of ethanol (96%). Mice in groups were pretreated with FTL (0.25, 0.5 and 1 mg/kg; i.p.), cimetidine (100 mg/kg; p.o.), or vehicle (0.9% of NaCl, 10 mL/kg; p.o.), 30 min before ethanol administration. They were sacrificed 30 min later, the stomachs excised, and the mucosal lesion area (mm2) measured by planimetry. Gastroprotection was assessed in relation to inhibition of gastric lesion area. To study the gastroprotective mechanism(s), its relations to capsaicin-sensitive fibers, endogenous prostaglandins, nitric oxide, sulphydryls, ATP-sensitive potassium channels, adrenoceptors, opioid receptors and calcium channels were analyzed. Treatments effects on ethanol-associated oxidative stress markers GSH and MDA were measured in gastric tissue. FTL afforded a dose-unrelated gastroprotection against the ethanol damage. However, it failed to prevent the ethanol-induced changes in the levels of GSH and MDA. It was observed that the gastroprotection by FTL was greatly reduced in animals pretreated with capsazepine, indomethacin, L-NAME or glibenclamide. Considering the results, it is suggested that the FTL could probably be a good therapeutic agent for the development of new medicine for the treatment of gastric ulcer.  相似文献   
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The present study was aimed at investigating the effect of experimental infection by Trypanosoma vivax in different stages of pregnancy, determining the pathogenesis of reproductive failure, and confirming transplacental transmission. We used 12 pregnant ewes distributed into four experimental groups: G1, was formed by three ewes infected with T. vivax in the first third of pregnancy (30 days); G2 comprised three infected ewes in the final third of pregnancy (100 days); G3 and G4 were composed of three non-infected ewes with the same gestational period, respectively. Each ewe of G1 and G2 was inoculated with 1.25 × 105 tripomastigotes. Clinical examination, determination of parasitemia, serum biochemistry (albumin, total protein, glucose, cholesterol, and urea), packed cell volume (PCV), serum progesterone, and pathological examination were performed. Placenta, amniotic fluid, blood and tissues from the fetuses and stillbirths were submitted to PCR. Two ewes of G1 (Ewe 1 and 3) presented severe infection and died in the 34th and 35th days post-infection (dpi), respectively; but both fetuses were recovered during necropsy. In G2, Ewe 5 aborted two fetuses on the 130th day (30 dpi) of pregnancy; and Ewe 6 aborted one fetus in the 140th day (40 dpi) of gestation. Ewes 2 and 4 delivered two weak lambs that died five days after birth. Factors possibly involved with the reproductive failure included high parasitemia, fever, low PCV, body score, serum glucose, total protein, cholesterol, and progesterone. Hepatitis, pericarditis, and encephalitis were observed in the aborted fetuses. The presence of T. vivax DNA in the placenta, amniotic fluid, blood, and tissues from the fetuses confirms the transplacental transmission of the parasite. Histological lesion in the fetuses and placenta also suggest the involvement of the parasite in the etiopathogenesis of reproductive failure in ewes.  相似文献   
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Plant Foods for Human Nutrition - Obesity is an important public health concern and is directly related with chronic noncommunicable diseases that affect the health of millions of people around the...  相似文献   
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This study investigated the secondary stress responses of Paralichthys orbignyanus exposed to ammonia and nitrite and after recovery. Fish were exposed to 0.12, 0.28, and 0.57 mg NH3‐N/L, or 5.72, 10.43, and 15.27 mg NO2‐N/L for 10 d followed by the same time length for recovery. Ammonia‐ and nitrite‐free water was used as a control treatment. Blood samples were collected after 1, 5, and 10 d of exposure and after recovery. Fish exposed to ammonia presented lower and higher glucose levels after 10 d of exposure and recovery, respectively. Ammonia induced initial and transient ionic disturbances and metabolic alkalosis. Nitrite exposure caused hyperglycemia, increased plasma K+ levels, and respiratory alkalosis, whereas metabolic acidosis was observed after recovery. Increased proportion of monocytes and/or granulocytes and reduced number of lymphocytes were demonstrated in fish exposed to 0.28 mg NH3‐N/L (Day 1) and 10.43 mg NO2‐N/L (Day 5) and after recovery in the 0.28 and 0.57 mg NH3‐N/L treatments. Exposure to ammonia decreased the proportion of granulocytes on Day 5. In conclusion, exposure to concentrations at 0.12 mg NH3‐N/L and 5.72 mg NO2‐N/L provoked physiological disorders in Brazilian flounder. Nonetheless, fish exposed to 5.72 mg NO2‐N/L following a 10‐d recovery period showed complete resumption of homeostasis.  相似文献   
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