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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Utilization of electrolytes to encourage early feed and water consumption in newly weaned piglets

Gigiel, Agnieszka 22 September 2010 (has links)
Four experiments were conducted to determine a management strategy for providing effective electrolyte concentrations in the drinking water of newly weaned piglets to encourage early fluid and feed intake [weaning age=19±1 d, n=360]. In Exp. 1, electrolytes (Vetoquinol, QC, Canada) were provided at the label dose of 60 ml/L of water for 0, 6, 12, 18 or 24 h on d1-d3. In Exp. 2, electrolytes were given ad lib at 100, 75, 50, 25 or 12.5 % of the label dose on d1-d3 (72 h). In Exp. 3, electrolytes, at the label dose, or water (control) were given ad lib on d1, d1 and d2, d1-d3, or d1 and d3. In Exp. 4, based on the results of the previous experiments, the most effective combinations of "hours/concentration/days"(12 h of 25 % or 50 % on d1 or alternate days) were tested. All piglets had water ad lib from d4-d14. In Exp. 1, higher feed disappearance was observed in the 0, 6 and 12 h/d than 18 h/d and 24 h/d electrolyte groups (P<0.05). In Exp. 2, by d14 piglets in the 12.5, 50, 75, and 100 % groups experienced lower weight gain and daily FI than those in the 25 % group (P<0.05). In Exp. 3, piglets that received electrolytes on d1 only had comparable FI to those in the water group (respectively; 64.55 g/pig/day vs. 75.59 g/pig/day; SEM=8.61). Overall, evidence indicated that weanlings tended to benefit from electrolyte administration at 25 % of the label dose and durational period of ≤ 12 h/d. However, in Exp. 4 testing neither 25 % or 50 % concentration for 12 h/d result in improved daily FI despite the increased FLI in groups given electrolytes on alternate days. The results suggest that high electrolyte intake occurred at the expense of feed intake.
2

Utilization of electrolytes to encourage early feed and water consumption in newly weaned piglets

Gigiel, Agnieszka 22 September 2010 (has links)
Four experiments were conducted to determine a management strategy for providing effective electrolyte concentrations in the drinking water of newly weaned piglets to encourage early fluid and feed intake [weaning age=19±1 d, n=360]. In Exp. 1, electrolytes (Vetoquinol, QC, Canada) were provided at the label dose of 60 ml/L of water for 0, 6, 12, 18 or 24 h on d1-d3. In Exp. 2, electrolytes were given ad lib at 100, 75, 50, 25 or 12.5 % of the label dose on d1-d3 (72 h). In Exp. 3, electrolytes, at the label dose, or water (control) were given ad lib on d1, d1 and d2, d1-d3, or d1 and d3. In Exp. 4, based on the results of the previous experiments, the most effective combinations of "hours/concentration/days"(12 h of 25 % or 50 % on d1 or alternate days) were tested. All piglets had water ad lib from d4-d14. In Exp. 1, higher feed disappearance was observed in the 0, 6 and 12 h/d than 18 h/d and 24 h/d electrolyte groups (P<0.05). In Exp. 2, by d14 piglets in the 12.5, 50, 75, and 100 % groups experienced lower weight gain and daily FI than those in the 25 % group (P<0.05). In Exp. 3, piglets that received electrolytes on d1 only had comparable FI to those in the water group (respectively; 64.55 g/pig/day vs. 75.59 g/pig/day; SEM=8.61). Overall, evidence indicated that weanlings tended to benefit from electrolyte administration at 25 % of the label dose and durational period of ≤ 12 h/d. However, in Exp. 4 testing neither 25 % or 50 % concentration for 12 h/d result in improved daily FI despite the increased FLI in groups given electrolytes on alternate days. The results suggest that high electrolyte intake occurred at the expense of feed intake.
3

Níveis de fibra em detergente neutro em rações para leitões na fase de creche / Levels of neutral detergent fiber in diets for piglets in nursery phase

Nepomuceno, Rafael Carlos January 2014 (has links)
NEPOMUCENO, Rafael Carlos. Níveis de fibra em detergente neutro em rações para leitões na fase de creche. 2014. 117 f. Tese (doutorado em zootecnia)- Universidade Federal do Ceará, Fortaleza-CE, 2014. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-04-22T19:07:50Z No. of bitstreams: 1 2014_tese_rcnepomuceno.pdf: 7901393 bytes, checksum: e16f51399ddce2290b9b82e4c5350ec5 (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-05-27T17:51:48Z (GMT) No. of bitstreams: 1 2014_tese_rcnepomuceno.pdf: 7901393 bytes, checksum: e16f51399ddce2290b9b82e4c5350ec5 (MD5) / Made available in DSpace on 2016-05-27T17:51:48Z (GMT). No. of bitstreams: 1 2014_tese_rcnepomuceno.pdf: 7901393 bytes, checksum: e16f51399ddce2290b9b82e4c5350ec5 (MD5) Previous issue date: 2014 / Two experiments were conducted involving 120 piglets castrated males, weaned at 21 days of age. In the first experiment where used 30 animals of average weight of 7.48 ± 0.46 kg with the objective of evaluating the effects of NDF levels in diets for piglets 21-42 days old on the pH and viscosity of the gastric and intestinal contents, the concentration of short chain fatty acids in cecal contents, gastrointestinal transit time of digesta, apparent digestibility of energy and nutrients in the diets, impacts on the intestinal mucosa, weight of digestive organ, productive performance, diarrhea occurrence, composition and deposition rate nutrients and energy body. In the second experiment 90 piglets of average body weight of 6.84 ± 0.47 kg with the objective of evaluating the effects of NDF levels in diets for piglets 21-70 days old on productive performance and occurrence of diarrhea. The piglets were distributed following a randomized block design with five treatments, considering the levels of neutral detergent fiber (NDF) of 8.5; 10.5; 12.5; 14.5 and 16.5% and six replications per treatment, one animal per plot, in the first trial, and three piglets per plot in the second test, and the initial weights of the animals the criterion used for the formation of blocks. It was found that levels of NDF did not affect the pH and viscosity of the digesta in the different sections of the gastrointestinal tract, as well as the concentration of short chain fatty acids. Quadratic effect was detected for villus height in the duodenum and jejunum and crypt depth in the jejunum, with a higher level ships in diets with 12.2% NDF. Effect linear increase was observed for the weight of the stomach and cecum and cólon. It was found that NDF levels below or above 10.2 to 13.5% reduced the transit time of digesta. Quadratic effect was observed in the digestibility of all variables, as well as weight gain and feed conversion of pigs at 70 days of age. In contrast, linear effect on the occurrence of diarrhea with the increased level of NDF in the diets was observed. The increased level of NDF caused a linear increase in fat in the carcass, blood and body, while the energy in the carcass, viscera and body showed an inverse response. Quadratic effect on deposition rates of nutrients and energy in the body, with the exception of mineral matter which linear decreasing effect mediated there was na increased level of NDF (Table 5), with the best deposition rates of water, protein gross, fat, and estimated in diets with 10.3 energies; 10.3; 11.8; 8.5 and 8.6% NDF, respectively Considering the maximum animal performance is concluded that the level of NDF in diets for pigs from 21 to 70 days of age should not exceed 10%. / Foram conduzidos dois experimentos envolvendo 120 leitões, machos castrados, desmamados aos 21 dias de idade. No primeiro experimento foram utilizados 30 animais de peso vivo médio de 7,48±0,46 kg com o objetivo de avaliar os efeitos de níveis de FDN em rações de leitões de 21 a 42 dias de idade sobre o pH e viscosidade dos conteúdos gástricos e intestinais, a concentração de ácidos graxos de cadeia curta no conteúdo cecal, tempo de trânsito gastrointestinal da digesta, digestibilidade da energia e nutrientes das rações, impactos sobre a mucosa intestinal, peso dos órgão digestivos, desempenho produtivo, ocorrência de diarreia, composição e taxa de deposição de nutrientes e energia corporal. No segundo experimento foram utilizados 90 leitões de peso vivo médio de 6,84±0,47 kg com o objetivo de avaliar os efeitos de níveis de FDN em rações de leitões de 21 a 42 dias de idade sobre o desempenho produtivo e ocorrência de diarreia. Em ambos os experimentos os leitões foram distribuídos seguindo um delineamento em blocos casualizados, em cinco tratamentos, considerando os níveis de fibra em detergente neutro (FDN) de 8,5; 10,5; 12,5; 14,5 e 16,5% e seis repetições por tratamento, sendo um animal por parcela, no primeiro ensaio, e, três leitões por unidade experimental, no segundo ensaio, sendo os pesos iniciais dos animais o critério utilizado para a formação dos blocos. Constatou-se que os níveis de FDN não afetaram o pH e viscosidade da digesta nas diferentes seções do trato gastrointestinal, bem como a concentração dos ácidos graxos de cadeia curta. Foi detectado efeito quadrático para altura de vilosidade no duodeno e jejuno e na profundidade de cripta do jejuno, com melhor nível estimado para as rações com 12,2% de FDN. Foi constatado efeito linear crescente para o peso do estômago, ceco e colón. Verificou-se que níveis FDN abaixo ou acima de 10,2 a 13,5% reduziu o tempo de trânsito da digesta. Foi observado efeito quadrático no coeficiente de digestibilidade para todas as variáveis, bem como no ganho de peso e conversão alimentar dos leitões aos 70 dias de idade. Em contrapartida, foi observado efeito linear decrescente da ocorrência de diarreia com o aumento do nível de FDN nas rações. O incremento do nível de FDN promoveu aumento linear do teor de gordura na carcaça, sangue e corpo, enquanto que a energia na carcaça, vísceras e corpo apresentou resposta inversa. Observou-se efeito quadrático nas taxas de deposição de nutrientes e energia no corpo, com exceção da matéria mineral que apresentou efeito linear decrescente a medida que houve aumento no nível de FDN, sendo as melhores taxas de deposição de água, proteína bruta, gordura, e energias estimadas em rações com 10,3; 10,3; 11,8; 8,5 e 8,6% de FDN, respectivamente. Tendo em vista o máximo desempenho dos animais conclui-se que o nível de FDN em rações para leitões de 21 a 70 dias de idade não deve ultrapassar 10%.
4

Dietary means for enhanced gastrointestinal health and function in weaned pigs: An evaluation of carbohydrase enzymes targeting non-starch polysaccharides

Kiarie, Elijah 07 May 2008 (has links)
A major challenge for the pig industry is to formulate starter diets that primarily fit the digestive capacity, maintain GIT health and promote growth without recourse to in-feed antimicrobials. Experiments were conducted to evaluate the efficacy of carbohydrase enzymes (CE) targeting non-starch polysaccharides (NSP) in enhancing gut health and function in piglets. First, an experiment was conducted to evaluate the effects of adding CE in piglet diets on growth performance, GIT bacterial activity and nutrient digestibility. Pigs fed diets containing CE had a higher ileal lactobacilli count, total organic acids concentrations, NSP digestibility and low ammonia compared with control. The effectiveness of CE targeting NSP was further evaluated using enterotoxigenic E. coli (ETEC) in a challenge model to evaluate the impact on gut health and function. Two approaches for the ETEC challenge were adopted; an in situ small intestine segments perfusion model and an in vivo model. Initially, a pilot study was conducted to establish and validate the in situ model. In the pilot study, conventional anti-diarrhea agents; fumaric acid, ZnO, egg yolk antibodies against ETEC K88 fimbriae and carbadox, attenuated fluid losses in ETEC-infected jejunal segments. Following the establishment of the in situ model, four experiments were conducted to study the effects NSP hydrolysis products (HP) from various feedstuffs (i.e. wheat, soybean meal, canola meal and flaxseed) on ETEC-induced secretory diarrhea. The results demonstrated that HP protected against ETEC-induced fluid and electrolyte losses. A further study was conducted to investigate the response of piglets fed diets containing HP and EYA singly or in combination upon oral challenge with ETEC. Feeding HP and EYA alone or in combination attenuated ETEC-enteritis symptoms such that piglets fed additives showed less pronounced acute phase responses and superior performance. Piglets fed diets containing additives had lower gastric pH, fewer ETEC adhered to ileal mucosa and lower incidence of diarrhea. Overall, reduction of intestinal pathogens or toxic bacterial metabolites contributes to enhanced GIT health and function. These novel results expand the scope of enzyme technology in animal nutrition within the new paradigm of dietary approaches to gut health and function.
5

Dietary means for enhanced gastrointestinal health and function in weaned pigs: An evaluation of carbohydrase enzymes targeting non-starch polysaccharides

Kiarie, Elijah 07 May 2008 (has links)
A major challenge for the pig industry is to formulate starter diets that primarily fit the digestive capacity, maintain GIT health and promote growth without recourse to in-feed antimicrobials. Experiments were conducted to evaluate the efficacy of carbohydrase enzymes (CE) targeting non-starch polysaccharides (NSP) in enhancing gut health and function in piglets. First, an experiment was conducted to evaluate the effects of adding CE in piglet diets on growth performance, GIT bacterial activity and nutrient digestibility. Pigs fed diets containing CE had a higher ileal lactobacilli count, total organic acids concentrations, NSP digestibility and low ammonia compared with control. The effectiveness of CE targeting NSP was further evaluated using enterotoxigenic E. coli (ETEC) in a challenge model to evaluate the impact on gut health and function. Two approaches for the ETEC challenge were adopted; an in situ small intestine segments perfusion model and an in vivo model. Initially, a pilot study was conducted to establish and validate the in situ model. In the pilot study, conventional anti-diarrhea agents; fumaric acid, ZnO, egg yolk antibodies against ETEC K88 fimbriae and carbadox, attenuated fluid losses in ETEC-infected jejunal segments. Following the establishment of the in situ model, four experiments were conducted to study the effects NSP hydrolysis products (HP) from various feedstuffs (i.e. wheat, soybean meal, canola meal and flaxseed) on ETEC-induced secretory diarrhea. The results demonstrated that HP protected against ETEC-induced fluid and electrolyte losses. A further study was conducted to investigate the response of piglets fed diets containing HP and EYA singly or in combination upon oral challenge with ETEC. Feeding HP and EYA alone or in combination attenuated ETEC-enteritis symptoms such that piglets fed additives showed less pronounced acute phase responses and superior performance. Piglets fed diets containing additives had lower gastric pH, fewer ETEC adhered to ileal mucosa and lower incidence of diarrhea. Overall, reduction of intestinal pathogens or toxic bacterial metabolites contributes to enhanced GIT health and function. These novel results expand the scope of enzyme technology in animal nutrition within the new paradigm of dietary approaches to gut health and function.
6

Caracterização genotípica e fenotípica de cepas de Escherichia coli associadas à diarreia pós-desmame em suínos / Genotypic and phenotypic characterization of Escherichia coli strains associated with from post-weaning swine

Moreno, Marina 24 February 2015 (has links)
A Escherichia coli é um dos principais agentes envolvidos na síndrome da diarreia pós-desmame em suínos, sendo a infecção de difícil controle devido à elevada capacidade deste agente em desenvolver e disseminar mecanismos de resistência aos antimicrobianos utilizados para o tratamento da doença. No presente estudo foi estabelecido o perfil de virulência de cepas de E. coli isoladas de 621 leitões com sintomas de diarreia na fase de creche (21 a 40 dias de vida), provenientes de 52 granjas de suínos no Brasil. Foram selecionadas 148 cepas de E. coli, positivas para fímbria F4 e /ou F18 e destas foi determinado o perfil de resistência à antimicrobianos por determinação da concentração inibitória mínima para os seguintes antimicrobianos: ampicilina, clindamicina, clortetraciclina, danofloxacina, enrofloxacina, florfenicol, gentamicina, neomicina, oxitetraciclina, sulfadimetoxina, espectinomicina, trimetoprima / sulfametoxazole, tiamulina, tilmicosina, tulatromicina, tilosina, ceftiofur e enrofloxacina. Dos 621 animais observados, 321 animais foram positivos para pelo menos um fator de virulência. Das cepas estudadas, todas as 148 foram resistentes a tilosina, clindamicina, tiamulina, tilmicosina e sulfadimetoxina. A frequência de cepas resistentes foi elevada também para o oxitetraciclina, clortetraciclina, danofloxacina, ampicilina e ao florfenicol. Considerando-se o fato de 100% das cepas terem apresentado resistência a mais de três classes de antimicrobianos pode-se concluir que todas as cepas de E.coli do presente estudo foram multirresistentes sendo frequente a resistência aos principais antimicrobianos utilizados na terapia da diarreia em leitões de creche / Escherichia coli is one of the agents involved in the syndrome of post-weaning diarrhea in swine. The infection is difficult to control because of high ability of this agent to develop and spread antimicrobial resistance mechanisms against commonly used antibiotics. This study has as goal determine the virulence profile of E. coli strains isolated of 621 piglets with diarrhea symptoms in the nursery with 21-40 days of age, from 52 pig farms in Brazil. Of the isolated strains, we selected 148 strains of E. coli, positive for F4 fimbriae and / or F18 and these were tested for antimicrobial resistance for determining the minimum inhibitory concentration for the following antibiotics: ampicillin, clindamycin, chlortetracycline, danofloxacin, enrofloxacin, florfenicol, gentamicin, neomycin, oxytetracycline, sulfadimethoxin, spectinomycin, trimethoprim / sulfamethoxazole, tiamulin, tilmicosin, tulathromycin, tylosin, ceftiofur and enrofloxacin. Of the 621 observed animals 321 animals were positive for at least one virulence factor. Of the studied strains, all 148 were resistant to tylosin, clindamycin, tiamulin, tilmicosin and sulfadimethoxin. The frequency of resistant strains was also high for oxytetracycline, chlortetracycline, danofloxacin, ampicillin and florfenicol. Considering the fact that 100% of the strains have shown resistance to more than three classes of antimicrobials can be concluded that all E. coli strains in this study were multidrug-resistant and are frequent the resistance to the main antimicrobials used in therapy of diarrhea in nursery pigs
7

Calcium anacardate as an alternative growth promoter for piglets at nursery phase / Anacardato de cÃlcio como promotor de crescimento alternativo para leitÃes na fase de creche

Amanda Veruska Silva de Matos 20 March 2015 (has links)
FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / The objective was to evaluate the calcium anacardate as an alternative growth promoter in feed for piglets at nursery phase, on performance, occurrence of diarrhea, serum parameters, intestinal morphology and pH of the gastrointestinal contents. A total of 60 piglets were used, weaned at 21 days of age, distributed among 5 treatments: negative control (CN) - feed without growth promoter inclusion; positive control (CP) - feed with antibiotic growth promoter (AGP); AC 0.4% - feed with 0.4% calcium anacardate; AC 0.8% - feed with 0.8% calcium anacardate; AC 1.2% - feed with 1.2% calcium anacardate, with 6 replicates per treatment, considering the pen containing 2 piglets as experimental unit. The experiment lasted 22 days, divided in period I (21-32 days) and period II (21-42 days). It was observed that the performance of piglets fed with calcium anacardate didnât differ from those fed with AGP. The inclusion of calcium anacardate from 0.8% in the feed resulted in serum globulin levels similar to those animals receiving the feed with AGP. Although the occurrence of diarrhea was lower in animals that received AGP, the villus height (VH) and villus height-to-crypt depth ratio (V/C) in the animals who received calcium anacardate in the diet was similar to the treatment with AGP. Calcium anacardate can act as a replacement for AGP in diets for piglets at nursery phase, considering that from the inclusion of 0.8% showed benefits in intestinal morphology and serum parameters of animals. / Objetivou-se avaliar os efeitos da utilizaÃÃo do anacardato de cÃlcio como promotor de crescimento alternativo em raÃÃes para leitÃes na fase de creche, quanto ao desempenho, ocorrÃncia de diarreia, parÃmetros sanguÃneos, morfologia intestinal e pH dos conteÃdos gastrintestinais. Foram utilizados 60 leitÃes desmamados aos 21 dias de idade, distribuÃdos entre 5 tratamentos : controle negativo (CN) â raÃÃo sem inclusÃo de promotor de crescimento; controle positivo (CP) â raÃÃo com inclusÃo de antibiÃtico promotor de crescimento (APC); AC 0,4% - raÃÃo com inclusÃo de 0,4% de anacardato de cÃlcio; AC 0,8% - raÃÃo com inclusÃo de 0,8% de anacardato de cÃlcio; AC 1,2% - raÃÃo com inclusÃo de 1,2% de anacardato de cÃlcio, com 6 repetiÃÃes por tratamento, considerando a gaiola contendo 2 animais como unidade experimental. O perÃodo experimental foi de 22 dias, sendo divididos em perÃodo I (21 a 32 dias) e perÃodo II (21 a 42 dias). Observou-se que o desempenho dos leitÃes alimentados com raÃÃo contendo anacardato de cÃlcio nÃo diferiu daqueles alimentados com raÃÃo contendo APC. A inclusÃo de anacardato de cÃlcio a partir de 0,8% na raÃÃo resultou em valores de globulina sÃrica semelhantes aos dos animais que receberam APC na raÃÃo. Embora a ocorrÃncia de diarreia tenha sido menor nos animais que receberam APC, os valores de altura de vilosidade (AV) e relaÃÃo altura de vilosidade / profundidade de cripta (AV/PC) nos animais que receberam anacardato de cÃlcio na raÃÃo foram similares ao tratamento com APC. O anacardato de cÃlcio pode atuar como um substituto aos APC em raÃÃes para leitÃes na fase de creche, considerando que a partir da inclusÃo de 0,8% houve benefÃcios na morfologia intestinal e nos parÃmetros sÃricos dos animais.
8

NÃveis de fibra em detergente neutro em raÃÃes para leitÃes na fase de creche / Levels of neutral detergent fiber in diets for piglets in nursery phase

Rafael Carlos Nepomuceno 09 May 2014 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Foram conduzidos dois experimentos envolvendo 120 leitÃes, machos castrados, desmamados aos 21 dias de idade. No primeiro experimento foram utilizados 30 animais de peso vivo mÃdio de 7,48Â0,46 kg com o objetivo de avaliar os efeitos de nÃveis de FDN em raÃÃes de leitÃes de 21 a 42 dias de idade sobre o pH e viscosidade dos conteÃdos gÃstricos e intestinais, a concentraÃÃo de Ãcidos graxos de cadeia curta no conteÃdo cecal, tempo de trÃnsito gastrointestinal da digesta, digestibilidade da energia e nutrientes das raÃÃes, impactos sobre a mucosa intestinal, peso dos ÃrgÃo digestivos, desempenho produtivo, ocorrÃncia de diarreia, composiÃÃo e taxa de deposiÃÃo de nutrientes e energia corporal. No segundo experimento foram utilizados 90 leitÃes de peso vivo mÃdio de 6,84Â0,47 kg com o objetivo de avaliar os efeitos de nÃveis de FDN em raÃÃes de leitÃes de 21 a 42 dias de idade sobre o desempenho produtivo e ocorrÃncia de diarreia. Em ambos os experimentos os leitÃes foram distribuÃdos seguindo um delineamento em blocos casualizados, em cinco tratamentos, considerando os nÃveis de fibra em detergente neutro (FDN) de 8,5; 10,5; 12,5; 14,5 e 16,5% e seis repetiÃÃes por tratamento, sendo um animal por parcela, no primeiro ensaio, e, trÃs leitÃes por unidade experimental, no segundo ensaio, sendo os pesos iniciais dos animais o critÃrio utilizado para a formaÃÃo dos blocos. Constatou-se que os nÃveis de FDN nÃo afetaram o pH e viscosidade da digesta nas diferentes seÃÃes do trato gastrointestinal, bem como a concentraÃÃo dos Ãcidos graxos de cadeia curta. Foi detectado efeito quadrÃtico para altura de vilosidade no duodeno e jejuno e na profundidade de cripta do jejuno, com melhor nÃvel estimado para as raÃÃes com 12,2% de FDN. Foi constatado efeito linear crescente para o peso do estÃmago, ceco e colÃn. Verificou-se que nÃveis FDN abaixo ou acima de 10,2 a 13,5% reduziu o tempo de trÃnsito da digesta. Foi observado efeito quadrÃtico no coeficiente de digestibilidade para todas as variÃveis, bem como no ganho de peso e conversÃo alimentar dos leitÃes aos 70 dias de idade. Em contrapartida, foi observado efeito linear decrescente da ocorrÃncia de diarreia com o aumento do nÃvel de FDN nas raÃÃes. O incremento do nÃvel de FDN promoveu aumento linear do teor de gordura na carcaÃa, sangue e corpo, enquanto que a energia na carcaÃa, vÃsceras e corpo apresentou resposta inversa. Observou-se efeito quadrÃtico nas taxas de deposiÃÃo de nutrientes e energia no corpo, com exceÃÃo da matÃria mineral que apresentou efeito linear decrescente a medida que houve aumento no nÃvel de FDN, sendo as melhores taxas de deposiÃÃo de Ãgua, proteÃna bruta, gordura, e energias estimadas em raÃÃes com 10,3; 10,3; 11,8; 8,5 e 8,6% de FDN, respectivamente. Tendo em vista o mÃximo desempenho dos animais conclui-se que o nÃvel de FDN em raÃÃes para leitÃes de 21 a 70 dias de idade nÃo deve ultrapassar 10%. / Two experiments were conducted involving 120 piglets castrated males, weaned at 21 days of age. In the first experiment where used 30 animals of average weight of 7.48 Â 0.46 kg with the objective of evaluating the effects of NDF levels in diets for piglets 21-42 days old on the pH and viscosity of the gastric and intestinal contents, the concentration of short chain fatty acids in cecal contents, gastrointestinal transit time of digesta, apparent digestibility of energy and nutrients in the diets, impacts on the intestinal mucosa, weight of digestive organ, productive performance, diarrhea occurrence, composition and deposition rate nutrients and energy body. In the second experiment 90 piglets of average body weight of 6.84 Â 0.47 kg with the objective of evaluating the effects of NDF levels in diets for piglets 21-70 days old on productive performance and occurrence of diarrhea. The piglets were distributed following a randomized block design with five treatments, considering the levels of neutral detergent fiber (NDF) of 8.5; 10.5; 12.5; 14.5 and 16.5% and six replications per treatment, one animal per plot, in the first trial, and three piglets per plot in the second test, and the initial weights of the animals the criterion used for the formation of blocks. It was found that levels of NDF did not affect the pH and viscosity of the digesta in the different sections of the gastrointestinal tract, as well as the concentration of short chain fatty acids. Quadratic effect was detected for villus height in the duodenum and jejunum and crypt depth in the jejunum, with a higher level ships in diets with 12.2% NDF. Effect linear increase was observed for the weight of the stomach and cecum and cÃlon. It was found that NDF levels below or above 10.2 to 13.5% reduced the transit time of digesta. Quadratic effect was observed in the digestibility of all variables, as well as weight gain and feed conversion of pigs at 70 days of age. In contrast, linear effect on the occurrence of diarrhea with the increased level of NDF in the diets was observed. The increased level of NDF caused a linear increase in fat in the carcass, blood and body, while the energy in the carcass, viscera and body showed an inverse response. Quadratic effect on deposition rates of nutrients and energy in the body, with the exception of mineral matter which linear decreasing effect mediated there was na increased level of NDF (Table 5), with the best deposition rates of water, protein gross, fat, and estimated in diets with 10.3 energies; 10.3; 11.8; 8.5 and 8.6% NDF, respectively Considering the maximum animal performance is concluded that the level of NDF in diets for pigs from 21 to 70 days of age should not exceed 10%.
9

Caracterização genotípica e fenotípica de cepas de Escherichia coli associadas à diarreia pós-desmame em suínos / Genotypic and phenotypic characterization of Escherichia coli strains associated with from post-weaning swine

Marina Moreno 24 February 2015 (has links)
A Escherichia coli é um dos principais agentes envolvidos na síndrome da diarreia pós-desmame em suínos, sendo a infecção de difícil controle devido à elevada capacidade deste agente em desenvolver e disseminar mecanismos de resistência aos antimicrobianos utilizados para o tratamento da doença. No presente estudo foi estabelecido o perfil de virulência de cepas de E. coli isoladas de 621 leitões com sintomas de diarreia na fase de creche (21 a 40 dias de vida), provenientes de 52 granjas de suínos no Brasil. Foram selecionadas 148 cepas de E. coli, positivas para fímbria F4 e /ou F18 e destas foi determinado o perfil de resistência à antimicrobianos por determinação da concentração inibitória mínima para os seguintes antimicrobianos: ampicilina, clindamicina, clortetraciclina, danofloxacina, enrofloxacina, florfenicol, gentamicina, neomicina, oxitetraciclina, sulfadimetoxina, espectinomicina, trimetoprima / sulfametoxazole, tiamulina, tilmicosina, tulatromicina, tilosina, ceftiofur e enrofloxacina. Dos 621 animais observados, 321 animais foram positivos para pelo menos um fator de virulência. Das cepas estudadas, todas as 148 foram resistentes a tilosina, clindamicina, tiamulina, tilmicosina e sulfadimetoxina. A frequência de cepas resistentes foi elevada também para o oxitetraciclina, clortetraciclina, danofloxacina, ampicilina e ao florfenicol. Considerando-se o fato de 100% das cepas terem apresentado resistência a mais de três classes de antimicrobianos pode-se concluir que todas as cepas de E.coli do presente estudo foram multirresistentes sendo frequente a resistência aos principais antimicrobianos utilizados na terapia da diarreia em leitões de creche / Escherichia coli is one of the agents involved in the syndrome of post-weaning diarrhea in swine. The infection is difficult to control because of high ability of this agent to develop and spread antimicrobial resistance mechanisms against commonly used antibiotics. This study has as goal determine the virulence profile of E. coli strains isolated of 621 piglets with diarrhea symptoms in the nursery with 21-40 days of age, from 52 pig farms in Brazil. Of the isolated strains, we selected 148 strains of E. coli, positive for F4 fimbriae and / or F18 and these were tested for antimicrobial resistance for determining the minimum inhibitory concentration for the following antibiotics: ampicillin, clindamycin, chlortetracycline, danofloxacin, enrofloxacin, florfenicol, gentamicin, neomycin, oxytetracycline, sulfadimethoxin, spectinomycin, trimethoprim / sulfamethoxazole, tiamulin, tilmicosin, tulathromycin, tylosin, ceftiofur and enrofloxacin. Of the 621 observed animals 321 animals were positive for at least one virulence factor. Of the studied strains, all 148 were resistant to tylosin, clindamycin, tiamulin, tilmicosin and sulfadimethoxin. The frequency of resistant strains was also high for oxytetracycline, chlortetracycline, danofloxacin, ampicillin and florfenicol. Considering the fact that 100% of the strains have shown resistance to more than three classes of antimicrobials can be concluded that all E. coli strains in this study were multidrug-resistant and are frequent the resistance to the main antimicrobials used in therapy of diarrhea in nursery pigs
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Fiber growth of goats as influenced by the doe’s genotype, plane of nutrition and physiological stage (gestation and lactation)

Livhuwani, Ngwekhulu 21 September 2010 (has links)
The aim of this thesis was to investigate how fiber growth of goats is determined by genotype, (purebred Angora and crossbred between Angora and Boer goat), physiological stages of the females from mid pregnancy until fifty days after the kids had been weaned and the plane of nutrition. Twelve Angora (pure bred) and ten Angora x Boer goat doe's with an initial mass of 28.70±4.42, between three and five years of age were used. Half of them received 120% NRC energy requirements and the other half received 80% requirements. Mohair patches of 100cm2 were collected from the animals at parturition, mid-lactation, weaning and fifty days post weaning. The fiber greasy weight started declining with commencement of lactation in crossbred animals of both high and low nutrition. The greasy mass again increased from the period of weaning until fifty days post weaning suggesting that crossbred animals do not produce a lot of fiber at the expense of fetal and kid growth. Since fiber production from the crossbred animals is lower, I recommend that the Angora genotype be increased to gain more fiber and further research be done on the topic. / Dissertation (MInstAgrar)--University of Pretoria, 2010. / Animal and Wildlife Sciences / unrestricted

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