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排序方式: 共有264条查询结果,搜索用时 20 毫秒
1.
Hilton C Diniz Neto Mayara C Lombardi Mariana M Campos Andrey P Lage Rodrigo O S Silva Elaine Maria Seles Dorneles Camila Flvia A Lage Wanessa A Carvalho Fernanda S Machado Luiz Gustavo R Pereira Thierry R Tomich Carolina P Ramos Ronnie A Assis Francisco Carlos F Lobato Jordana A Santana Ethiene Luiza S Santos Rafaella S Andrade Sandra G Coelho 《Journal of animal science》2021,99(5)
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
2.
de Jesus WC do Vale FX Coelho RR Hau B Zambolim L Costa LC Filho AB 《Phytopathology》2001,91(11):1045-1053
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
3.
Paranhos-Silva M Oliveira GG Reis EA de Menezes RM Fernandes O Sherlock I Gomes RB Pontes-de-Carvalho LC dos-Santos WL 《Veterinary parasitology》2003,114(2):97-111
In this study, we compare the development of infection and/or disease in Beagle dogs intradermally infected with Leishmania chagasi, in the presence or absence of Lutzomyia longipalpis saliva, with those of intravenously infected animals.Spleen samples of all the animals inoculated with parasites had positive polymerase chain reaction tests for Leishmania DNA. Positive spleen cultures for Leishmania were detected earlier (P < or = 0.018) and were more frequent (five out of the five animals) in intravenously infected animals than in the intradermally infected animals, in presence (two out of the six animals) or absence (three out of the five animals) of salivary gland lysate of L. longipalpis. Significant increase in serum antibodies against Leishmania was observed only in the intravenously infected group (P = 0.004). In addition, dogs with infection confirmed by isolation of amastigotes or detection of parasite DNA were, nevertheless, negative for anti-Leishmania antibodies up to 5 months or more after infection. Only animals of the intravenously infected group developed progressive decreases in hematocrit (Pearson r = -0.8076, P = -0.0026) and hemoglobin (Pearson r = -0.8403, P = 0.0012) during the infection period. No significant difference in the course of infection was observed between groups of intradermally infected animals. The data presented herein confirms that the intradermal inoculation of dogs with Leishmania produces an asymptomatic form of infection. It also fails to show an advantage in using L. longipalpis saliva as an infection-enhancing agent in experimental canine leishmaniasis. 相似文献
4.
Forrest W. Nutter Jr Paul D. Esker Rosalee A. Coelho Netto 《European journal of plant pathology / European Foundation for Plant Pathology》2006,115(1):95-103
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
5.
Shibata Marília Coelho Cileide M. M. de Garighan Julio A. dos Santos Henrique P. Araldi Cristhyane G. Maraschin Marcelo 《New Forests》2021,52(5):759-775
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
6.
Daiane Güllich Donin Raquel de Arruda Leme Alice Fernandes Alfieri Geraldo Camilo Alberton Amauri Alcindo Alfieri 《Tropical animal health and production》2014,46(3):523-528
Porcine teschovirus (PTV), Porcine sapelovirus (PSV) and Enterovirus G (EV-G) have been associated with enteric, respiratory, reproductive and neurological disorders. Although Brazil is the world’s fourth largest producer and exporter of pork, no information on the occurrence of PTV, PSV and EV-G infections is available for Brazilian pig herds. This study aimed to investigate the occurrence of Porcine enteric picornavirus infections in pig farms located in three distinct geographical regions of Brazil. Forty randomly selected diarrhoeic and normal consistency faeces of suckling (n?=?22) and nursery (n?=?18) pigs from farms located in 21 distinct cities of the Southern, Southeast, and Midwest regions of Brazil were evaluated by nested-RT-PCR assays. Suckling piglets presented the expected amplicon size for PTV (158 bp) and EV-G (313 bp) in single and mixed infections in 40.9 % (9/22) of the faecal samples. PSV amplicon (212 bp) was not detected in this age group. For nursery pigs, Porcine enteric picornaviruses amplicons were present in 77.8 % (14/18) of the faecal samples. PTV and EV-G were detected in single and mixed infections, while PSV was detected only in two samples in co-infection with PTV and EV-G in this age group. The Brazilian regions evaluated presented at least two of the tested viruses. Sequencing analysis revealed high similarities to the related viruses (95.3 to 99.2 % for PTV, 94.2 to 98.5 % for PSV and 86 to 100 % for EV-G). For the first time PTV, PSV and EV-G have been molecularly detected and characterised in pig faecal samples in Brazil. 相似文献
7.
The in vitro hemolytic activity of Tritrichomonas foetus was investigated. The parasite was tested against human erythrocytes of groups A, B, AB, and O, and against erythrocytes of nine adult animals of different species (the rabbit, rat, chicken, cat, dog, swine, horse, bovine, and sheep). The results showed that T. foetus strains (ATCC KV1, K, PAL, 5022, RJ, 90) did not present any hemolytic activity against any human erythrocyte group nor against rabbit, rat, chicken, cat, dog and swine erythrocytes. T. foetus strains, however, lysed horse, bovine, and sheep erythrocytes. No hemolysin released by the parasites could be identified. Hemolysis did not occur with trichomonad culture supernatants, with sonicated extracts of T. foetus, nor with killed organisms. Scanning electron microscopy (SEM) showed that human erythrocytes did not adhere to the trophozoites, in contrast horse erythrocytes adhered to the surface of the parasites and were phagocytosed for up to 90 min. The parasites are able to exert their cytopathic effects through: (a) physical contact established between the two cell surfaces, (b) toxins released from parasites into the interaction media, or (c) the association of both mechanisms. Further studies are necessary to clarify the importance of the hemolytic activity in the biology of T. foetus. 相似文献
8.
de Vasconcellos Abdon AP Coelho de Souza G Noronha Coelho de Souza L Prado Vasconcelos R Araújo Castro C Moreira Guedes M Pereira Lima RC de Azevedo Moreira R de Oliveira Monteiro-Moreira AC Rolim Campos A 《Fitoterapia》2012,83(3):604-608
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
9.
Taciana MF Silva Roberio G Olinda Carla MF Rodrigues Ant?nio CL Camara Francisco C Lopes Wesley AC Coelho Múcio FB Ribeiro Carlos IA Freitas Marta MG Teixeira Jael S Batista 《Veterinary research》2013,44(1):1
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
10.
Robson RV Alves Tatiana Soares Elinaldo FL Bento Ricardo S Roldan‐Filho Brbara SS Souza Marcele KN Lima Jssica S Nascimento Luana CBB Coelho Roberto A S Thmarah A Lima Gabriel GA Gonalves Fbio A Brayner Luiz C Alves Daniela MAF Navarro Thiago H Napoleo Patrícia MG Paiva 《Pest management science》2020,76(2):730-736