Made available in DSpace on 2014-06-11T19:23:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-21Bitstream added on 2014-06-13T19:08:43Z : No. of bitstreams: 1 bassetto_cc_me_botib.pdf: 208428 bytes, checksum: c0a49413b34832ecc2265e91d1560b39 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Neste estudo avaliou-se a eficácia de uma vacina constituída de glicoproteínas obtidas da membrana do intestino de Haemonchus contortus em bezerros desafiados com H. contortus ou H. placei. Bezerros holandeses machos, criados livres de infecções por helmintos, foram distribuídos em quatro grupos com nove animais cada. Dois grupos foram vacinados com 50 μg do imunógeno diluído no adjuvante QuilA, enquanto os outros dois grupos foram os controles, receberam apenas adjuvante. A vacina foi administrada três vezes com intervalo de 21 dias entre as aplicações. Os bezerros foram artificialmente infectados sete dias após a última imunização e sacrificados para contagem dos vermes 43 dias depois. Os bezerros de um dos grupos vacinados receberam 8000 larvas infectantes (L3) de H. contortus enquanto os do outro grupo foram infectados com o mesmo número de L3 de H. placei. Os controles foram infectados na mesma ocasião com o mesmo número de L3 de H. contortus ou H. placei. A vacinação reduziu significativamente a contagem de ovos por grama de fezes (OPG) e a carga parasitária (P<0,01). A titulação de anticorpos nos animais controle permaneceu perto de zero enquanto nos animais vacinados verificou-se elevada titulação de anticorpos no soro. Os bezerros vacinados e desafiados com H. contortus não eliminaram ovos nas amostras de fezes, enquanto os controles apresentaram média máxima (± erro padrão) de 61,1 (±42,3) OPG 31 dias após a infecção. A partir deste dia, a contagem de OPG diminuiu progressivamente neste grupo controle com apenas um animal eliminando ovos nas fezes 42 dias após a infecção. Nos controles de H. placei, o ápice na contagem de OPG ocorreu 35 dias após a infecção (61,1 ± 21,7) e permaneceu relativamente constante até o final do estudo, enquanto no grupo vacinado apenas dois animais eliminaram ovos nas fezes, na última coleta. Os animais controle... / This study evaluated the efficacy of a vaccine containing integral membrane glycoproteins from the intestine of Haemonchus contortus in calves challenged with H. contortus or Haemonchus placei. Males Holstein calves, raised worm free, were distributed into four groups with nine animals each. Two groups were vaccinated with 50 μg of antigen diluted on QuilA adjuvant, while the others two groups were the controls and received only adjuvant. The vaccine was administered three times 21 days apart. Either vaccinated or not and challenged with either 8,000 H. contortus or H. placei infective larvae. The calves were challenged 7 days after the last immunization and killed for worm counts 43 days later. Vaccination significantly reduced faecal egg counts (FEC) and worm burdens (P< 0.01). Antibody titres in the calves control stayed close to zero meanwhile in the calves vaccinated was observed high antibody titres in the serum. Calves vaccinated and challenged with H. contortus did not shed eggs in faecal samples, while the controls showed a maximum mean (± standard error) FEC of 61.1 (±42.3) at 31 days post infection. Then, FEC progressively declined in this group with only one animal shedding eggs in faeces 42 days post infection. With H. placei the controls FEC peaked at 35 days post infection (61.1 ±21.7) and remained relatively constant until the end of the study, while in the vaccinated group only two animals shed eggs and only on the last collection date. With H. placei the controls contained a mean of 551.1 (±93.7) parasites, while the vaccinates had 174.4 (±56.3) worms. The establishment rate of H. contortus was lower than that of H. placei (P< 0.01) with an average of 163.9 (±39.4) and 74.4 (±20.4) specimens in the control and vaccinated groups, respectively. It was concluded that vaccination of calves with antigens obtained from H. contortus conferred protection against both H. placei and H. contortus

Made available in DSpace on 2014-06-11T19:23:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-05-26Bitstream added on 2014-06-13T20:49:48Z : No. of bitstreams: 1 silva_mb_me_botib.pdf: 435647 bytes, checksum: 214eaf077d57cf98dfcad34295798f53 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O estudo foi conduzido no intuito de avaliar a resistência e o desempenho produtivo de cordeiras puras Santa Inês (SI), Ile de France (IF) e animais produtos do cruzamento entre matrizes Santa Inês e reprodutores Dorper (DOxSI), Ile de France (IFxSI), Suffolk (SUxSI) e Texel (TExSI) artificialmente infectadas por Haemonchus contortus. Foram utilizadas cento e oito cordeiras com idade inicial de três meses. O experimento foi dividido em duas fases. Na primeira fase (18/09/2007 a 19/12/2007) os animais foram infectados com 500 larvas infectantes (L3) de H. contortus, três vezes por semana (segunda feira, quarta feira e sexta feira), totalizando 20, 500 L3. Após um período de 26 dias de suspensão das infecções, iniciou-se a segunda fase do experimento (14/01/2008 a 11/02/2008), quando os animais foram desafiados com uma dose única de 10, 000 L3, seguido de infecções seriadas com 1, 000 L3, três vezes por semana. Ao final do experimento totalizou-se 41, 500 L3 administradas a cada animal. Animais controles de cada um dos grupos genéticos foram mantidos livres de infecções helmínticas. Inicialmente as cordeiras receberam dieta de 16% PB, na proporção 90% concentrado e 10% volumoso ad libitum, na segunda fase a dieta passou a ser restrita, na proporção 50% de concentrado e 50% de volumoso. A cada 14 dias, o desempenho dos animais foi avaliado e exames parasitológicos e hematológicos foram realizados. Ao final do experimento, os animais foram sacrificados para a recuperação, contagem e classificação dos parasitas e para a colheita de amostras de tecido e muco do abomaso para análises histológicas e imunológicas. Os animais SUxSI mostraram-se os mais susceptíveis às infecções, demonstrando maior prejuízo do ponto de vista produtivo. Animais IF mostraram-se ineficientes em impedir o estabelecimento e desenvolvimento da infecção, contudo, seu desempenho produtivo... / This trial was carried out to evaluate the resistance status and produtivity to a artificial infection with Haemonchus contortus in purebred Santa Ines (SI) and Ile de France (IF) lambs, also in animals produced by crosses of Santa Ines dams and rams Dorper (DOxSI), Ile de France (IFxSI) Suffolk (SUxSI) and Texel (TEXSI) breed. The experiment was divided into two phases. At first, (18/09/2007 to 19/12/2007), a total of 108 three-month-old worm-free lambs were infected with 500 third-stage larvae (L3), three times a week, totaling 20.500 larvaes. After a period of 26 days of suspension in infections, began the second phase (14/01/2008 the 11/02/2008), when the lambs were challenged with trickle infection of 10.000 L3, followed by sequential infections with 1000 L3, a total of 2100 larvae. At the end of the experiment, each animal received 41.500 L3. Control animals were kept free of helminth infections. Initially, the lambs received a diet with 16% CP, the proportion was 90% concentrate and 10% forage ad libitum. In the second phase, the diet became restricted in the proportion of 50% concentrate and 50% forage. Every fourteen days, animals were weighed and blood and faecal samples were collected for measurement of parasitological and hematological tests. Respectively, twenty two weeks after infections, the animals were slaughtered to determine the worm burden and sampling of tissue and mucus from the abomasums were collected to histological and immunological analysis. Parasitological and productive results showed that SUxSI lambs were most susceptible to nematode infections. The IF group were ineffective in preventing the establishment and development of infection, however, its growth performance was superior to the other genetic groups, thus, this animals were classified as tolerant to infection. The SI group were the most resistant, with low FEC and worm burden and hematologic ... (Complete abstract click electronic access below)

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The blood feeding nematode Haemonchus contortus infects the abomasum of small ruminants and compartment three (C-3) of camelids. Heavy infections may cause severe anemia and death. Alpacas were first introduced into the U.S. in the 1980s. Although not true ruminants, alpacas may become infected with H. contortus and develop the same clinical signs as sheep and goats. Even though alpacas may become infected with the parasite, prior research by Hill et al. (1993) and Green et al. (1996) indicates alpacas may be more resistant to parasitic infection because they found lower numbers of eggs in the feces of alpacas compared to small ruminants. For our research, we hypothesized that given the same exposure to experimental infection, alpacas would be less susceptible than sheep to H. contortus. Experiment 1 was conducted with adult male alpacas (23) and sheep (12) housed in pens to prevent additional exposure to H. contortus. All animals were dewormed orally with a cocktail of fenbendazole, levamisole, and ivermectin. Haemonchus contortus infective larvae were administered orally to alpacas and rams in the following groups:1) 20,000 larvae as a single dose (bolus, n=6 both alpacas and sheep), 2) 20,000 larvae in daily doses of 4,000 larvae for 5 days (trickle, n=5 for alpacas, n=6 for sheep). Two additional groups of alpacas (n=6 each) received either 50,000 larvae as a bolus infection, or in daily doses of 10,000 larvae for 5 days (trickle). Fecal egg counts (FEC) were determined every 2 days from 14 to 42 days post infection (PI) and then at 5 day intervals until day 62 PI. Packed cell volume (PCV), FAMACHA scores, weight, and body condition scores were evaluated weekly. In general, mean FEC were lower in alpacas than sheep (p<0.01), and mean alpaca PCV was affected less by infection than sheep PCV. Experiment 1 results are consistent with our hypothesis that alpacas are less susceptible to H. contortus infection than sheep; however we were unable to determine whether alpaca FEC reflected fewer adult worms or only reduced H. contortus egg production compared to sheep. Experiment 2 was conducted with 16 alpacas and 12 rams and all animals were orally dewormed as in Experiment 1. Haemonchus contortus infective larvae were administered orally to alpacas in the following groups: 1) 20,000 larvae as a single dose (bolus, n=8), and 2) 20,000 larvae in daily doses of 4,000 larvae for 5 days (trickle, n=8). Ram groups (n=6 each) were the same as the alpaca groups. Fecal egg counts were determined at 5 day intervals from days 14 to 49 PI for bolus infected animals and to day 54 PI for trickle infected animals. FAMACHA scores were evaluated weekly. Packed cell volume was evaluated at the beginning and end of the study. All animals were euthanized 49 days after the last infection day. At euthanasia, abomasa and C-3 were harvested for determination of total worm burden and the pH was determined for each sheep rumen and abomasum and each alpaca C-1 and C-3. Mean FEC and total worm burden were significantly lower in alpacas than sheep (p<0.0001 for both FEC and total worm burden). Rumen pH in sheep was higher than C-1 pH in alpacas, but abomasal pH in sheep was significantly lower than C-3 pH in alpacas. Bolus infected sheep had lower FAMACHA scores than the other groups, and PCV was lower on the last day of sampling than the first day of sampling in all groups. The results of Experiment 2 also support our hypothesis that alpacas are less susceptible to H. contortus infection than sheep. However, it is unclear whether the differences are the result of physiological stomach differences between host species or whether other factors, such as immunity or parasite strain are important. / Master of Science

Resumo: O uso indiscriminado de anti-helmínticos tem resultado no surgimento de parasitas com resistência aos princípios ativos existentes no mercado. Dessa forma, este trabalho teve por objetivo avaliar in vitro o potencial antiparasitário de extratos vegetais sobre ovos e larvas do parasita gastrintestinal de ovinos, Haemonchus contortus e do parasita de ratos Strongyloides venezuelensis. Os extratos vegetais de Carapa guianensis, Hura crepitans, Lippia sidoides, Mentha piperita e Piper tuberculatum, produzidos em diferentes instituições de pesquisa, foram analisados quimicamente e testados in vitro pelos testes de inibição de eclodibilidade (EHT) e de desenvolvimento larvar (TDL) em H. contortus. A ação anti-helmíntica do extrato de P. tuberculatum (150 e 250 mg.Kg-1 de peso corporal) foi avaliada em Rattus norvegicus infectados experimentalmente com S. venezuelensis. No EHT, as CL50 e CL90 (concentrações letais que matam 50 e 90% dos ovos) dos extratos foram as seguintes: 0,031 e 0,09 mg.ml-1 para P. tuberculatum, 0,04 e 0,13 mg.ml-1 para L. sidoides, 0,037 e 0,10 mg.ml-1 para M. piperita, 2,16 e 17,13 mg.ml-1 para H. crepitans e 2,03x10-6 e 1,22x10-12 mg.ml-1 para C. guianensis. No TDL, as CL50 e CL90 (concentrações letais que matam 50 e 90% das larvas) foram respectivamente: 0,02 e 0,031 mg.ml-1 para P. tuberculatum, 0,002 e 0,04 mg.ml-1 para L. sidoides, 0,018 e 0,03 mg.ml-1 para M. piperita, 0,36 e 0,91 mg.ml-1 para H. crepitans e 17,65 e 1,890 mg.ml-1 para C. guianensis. O extrato de P. tuberculatum apresentou as seguintes substâncias: (Z)-piplartina, (E)-piplartina, 8,9-dihidropiplartina, piperina, 10,11-dihidropiperina; 5,6 dihidropiperlongumina e pelitorina. Os principais compostos dos óleos essenciais foram: timol (76,6%) para L. sidoides, mentol (27,5%) para M. piperita e ácido oléico (46,8%) para C. guianensis. Em relação ao teste in vivo, ambas as doses do extrato... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The indiscriminate use of anthelmintics has resulted in the establishment of parasite resistance. Thus, this study aimed to evaluate the in vitro antiparasitic effect of plant extracts on Haemonchus contortus of sheep and in vivo on rats infected with Strongyloides venezuelensis. The plant extracts from Piper tuberculatum, Lippia sidoides, Mentha piperita, Hura crepitans and Carapa guianensis, produced in different research institutions, were chemically analyzed and evaluated through the egg hatch test (EHT) and larval development test (LDT) in H. contortus. P. tuberculatum (150 and 250 mg.Kg-1 of body weight) was evaluated for its anthelmintic action in Rattus norvegicus experimentally infected with S. venezuelensis. In the EHT, the LC50 and LC90 (letal concentration that kill 50 and 90% of the eggs) from extracts were respectively as follow: 0.031 and 0.09 mg.ml-1 for P. tuberculatum, 0.04 and 0.13 mg.ml-1 for L. sidoides, 0.037 and 0.10 mg.ml-1 for M. piperita, 2.16 and 17.13 mg.ml-1 for H. crepitans and 2.03x10-6 and 1.22x10-12 mg.ml-1 for C. guianensis. In the LDT, the LC50 and LC90 (letal concentration that kill 50 and 90% of the larvae)were respectively: 0.02 and 0.031 mg.ml-1 for P. tuberculatum, 0.002 and 0.04 mg.ml-1 for L. sidoides, 0.018 and 0.03 mg.ml-1 for M. piperita, 0.36 and 0.91 mg.ml-1 for H. crepitans and 17.65 and 1890 mg.ml-1 for C. guianensis. The extract from P. tuberculatum showed the following substances: piperamides as (Z)-piplartine, (E)-piplartine, 8.9-dihydropiplartine, piperine, 10.11-dihydropiperine; 5.6 dihydropiperlongumine and pellitorine. The major compounds of the essential oils were thymol (76.6%) for L. sidoides, menthol (27.5%) for M. piperita and oleic acid (46.8%) for C. guianensis. Regarding the in vivo test, both doses of P. tuberculatum extract did not cause any significant reduction (P>0.05) in worm burden and egg count... (Complete abstract click electronic access below) / Orientador: Alessandro Francisco Talamini do Amarante / Coorientador: Ana Carolina de Souza Chagas / Banca: Kátia Denise Saraiva Bresciani / Banca: Lucia Helena O'Dwyer de Oliveira / Mestre