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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.
341

Ajuste de modelos nÃo-lineares para descriÃÃo da curva de crescimento de diferentes grupos geneticos de novilhas holandÃs x gir / Adjustment of nonlinear models for description of the curve of growth of different genetic groups of heifers dutch x to gir

Bartolomeu Neto Oliveira Martins 25 July 2008 (has links)
FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / As informaÃÃes utilizadas neste estudo foram referentes aos dados de pesos de 228 novilhas leiteiras de diferentes grupos genÃticos das raÃas Holandesa e Gir (1/2, 3/4, 5/8, 7/8 e 15/16 HolandÃs x Gir), com o objetivo de ajustar modelos para descrever as curvas de crescimento de cada um dos grupos genÃticos. Para descriÃÃo das curvas de crescimento em funÃÃo do peso e idade desses animais foram ajustados os modelos de Brody, Von Bertalanffy, Richards, LogÃstico e Gompertz. O mÃtodo utilizado para o ajuste foi o interativo de Gauss Newton, por meio da tÃcnica dos modelos nÃo lineares usando-se o procedimento NLIN (SAS, 2001). AdequaÃÃo dos modelos foi observada atravÃs dos desvios encontrados atravÃs da diferenÃa entre os valores dos pesos estimados pelos modelos e os pesos observados nas pesagens dos animais nas idades 1, 210, 240, 270, 300, 330, 360, 390, 420 e 450 dias. Foi ainda avaliado, qual grupo genÃtico mostrou-se ser mais passÃvel a estimaÃÃo de pesos por modelos nÃolineares. O modelo LogÃstico foi o que melhor se adequou a maioria dos grupos genÃticos HolandÃs x Gir, pois apesar de superestimar os valores dos pesos, foi o mais indicado para representar pesos de animais 5/8, 7/8 e 15/16 HolandÃs x Gir. O grupo genÃtico 1/2 HolandÃs x Gir se apresentou como o mais passÃvel de estimaÃÃo atravÃs dos modelos estudados, em virtude de ser bem representado por todos os modelos, principalmente pelo modelo de Von Bertalanfy / The sub-basins of the Cipà and Carrapateira belong to the districts of Barra Nova and Santo AntÃnio, which are part of Tauà Town in Cearà State, Brazil. These sub-basins are situated in one of the most degraded areas in Tauà Town, according to studies of the WAVES Project. Tauà Town has 1,906.3 km of degraded areas susceptible to desertification, what represents 44.3% of the municipal area, being characterized, according to the indexes established by the United Nations Organization, as a semi-arid area with a high critical index (0.4), what expresses the fragility of the dry lands. It has the following natural geo-ecological limitations: predominance of rocks having a crystalline base, average temperature around 25ÂC to 28ÂC, enabling a high evaporation rate and, as a result, negative values in the annual water balance; shallow and stony soils; a degraded ciliary plant cover due to the secular agro-extractivist activity, favoring sediment deposition in the riverâs bed and the river marginsâ widening, what endangers the water and pedological potential of the region. The combined action of the weather, of the geological conditions and the shallow soils of the region produces a fragile ecosystem, which reflects on the vegetation in the area, in which the caducifolia formation, with an arboreous and shrubby physiognomy, is unable to offer protection to the soils against the erosive effects, as observed in the study area. Because the ciliary vegetation is seriously threatened by the inadequate soil use, there is a need of detailed studies, such as: floristic composition and structure of the community, to check the plant community's condition in its current state in order to enable its rational use and sustainability in view of the unbalance in which it is. It is worth pointing out that the protection of the ciliary forest is of utmost importance for the good condition of water resources. It is important to preserve and restore the forests along the rivers and around lakes and reservoirs because that vegetation brings lots of benefits to the ecosystem, having the function of protecting the biotic and abiotic natural resources. This way, the research had the following main objectives: a) to analyze the ecosystem of the ciliary forest of the brooks Cipà and Carrapateiras, in order to obtain indicators of environmental degradation by checking the effects of agricultural activities and of the vegetable extractivism on the conditions of the potential communities of that vegetation conditions, combining those activities with other environmental factors, and; b) to make a phytosociological survey of the ciliary forest, supplying information to a database that leads to the sustainable land use to avoid or stop the degradation process, enabling a better life quality for the local population. The phytosociological studies showed significant differences between the two sample areas, in which the forest of the brook Cipà was more conserved with specimen of the ciliary forest, while the forest of the brook Carrapateiras totally is completely uncharacterized because of the high anthropic action.
342

Avaliação de diferentes protocolos de extração de DNA para detecção de Brucella abortus a partir de diferentes tecidos de vacas infectadas experimentalmente com a cepa 2308 / Evaluation of different protocols of DNA extraction for Brucella abortus detection from different tissues from experimentally infected cows with 2308 strain

Maria Del Pilar Vejarano Ruibal 19 June 2009 (has links)
Este estudo comparou o desempenho de quatro protocolos de extração de DNA a partir de homogeneizados de diferentes órgãos provenientes de vacas infectadas experimentalmente com a B. abortus 2308. Os protocolos de extração comparados foram o método de GT (lise com isotiocianato de guanidina), Boom (lise com GT e tratamento com suspensão carreadora Diatomaceous earth), PK (lise com proteinase K) e Santos (lise por fervura e congelamento com nitrogênio líquido). Foram constituídos os grupos padrão ouro positivo e negativo baseados na bacteriologia clássica e compostos por: 54 cotilédones (27 pos. e 27 neg.), 39 linfonodos supra mamários (12 pos. e 27 neg.), 44 pré-escapulares (17 pos. e 27 neg.), 33 fígados (6 pos. e 27 neg.), 37 baços (10 pos. e 27 neg.), e 34 úberes (7 pos. e 27 neg.). Todas as amostras foram submetidas aos quatro protocolos de extração e a um mesmo processo de amplificação com os primers B4 e B5. Nos resultados consolidados por órgãos, a proporção de positivos no cotilédone foi maior do que a encontrada no linfonodo supramamário (p=0,0001), linfonodo pré-escapular (p<0,0001), fígado (p=0,0006), baço (p<0,0001) ou úbere (p=0,0019). Os resultados acumulados para os métodos de extração mostraram que o protocolo de Santos teve maior sensibilidade relativa do que o método de Boom (p=0,003) e GT (p=0,0506), e foi igual ao PK (p=0,2969). As demais comparações de proporções não resultaram em diferenças estatisticamente significantes. No estudo verificou-se amostas positivas a PCR e negativas ao isolamento e viceversa. Assim, apesar das desvantagens do método bacteriológico clássico, a melhor estratégia para o diagnóstico direto da infecção de vacas por B. abortus em homogeneizado de órgãos é a utilização conjunta do isolamento e da PCR, examinando os cotilédones e utilizando os métodos de extração de DNA Santos ou PK. / This study compared the performance of four protocols of DNA extraction from suspensions of different tissues from experimentally infected cows with 2308 strain. The compared extraction protocols were GT protocol (lyse with guanidine isotiocianate), Boom (lyse with GT and treated with the carrying suspension Diatomaceous earth), PK (lise with proteinase K) and Santos (lyse by boiling and freezing with liquid nitrogen). Based on classical bacteriology, positive and negative gold standard groups were built and consisted of 54 cotyledons (27 pos. and 27 neg.), 39 supramammary lymph nodes (12 pos. and 27 neg.), 44 prescapulars (17 pos. and 27 neg.), 33 livers (6 pos. and 27 neg.), 37 spleens (10 pos. and 27 neg.), and 34 udders (7 pos. and 27 neg.). All the samples were submitted to the four DNA extraction protocols and the same amplification process using the primers B4 and B5. According to consolidated results by tissue, the proportion of positives in cotyledon was bigger than supramammary lymph node (p=0,0001), prescapular lymph node (p<0,0001), liver (p=0,0006), spleen (p<0,0001) and udder (p=0,0019). The consolidated results for the extraction methods show that Santos protocol had bigger relative sensitivity than Boom method (p=0,003) and GT (p=0,0506), and was equal than PK (p=0,2969). There were not significant statistical differences in the others comparisons of proportions. In the study, PCR-positive and isolation-negative samples and vice-versa were verified. However, the disadvantages of the classic bacteriological method, the best strategy for direct diagnosis of the infection of cows for B. abortus in homogenized of tissues is combined use of isolation and PCR, examining the cotyledons and using the methods of DNA extraction from Santos or PK.
343

Efeito do intervalo entre a inseminação e a ovulação na taxa de concepção de vacas Nelore inseminadas em tempo fixo com sêmen sexado / Effect of interval between insemination and ovulation in conception rates in Nelore cows timed AI with sex-sorted semen

Kedson Alessandri Lobo Neves 20 September 2010 (has links)
A identificação do momento mais apropriado para realizar a inseminação artificial em tempo fixo (IATF) utilizando sêmen sexado pode aumentar a prenhez por inseminação (P/IA) e aumentar a utilização do sêmen sexado em fazendas de corte. Este trabalho teve por objetivo avaliar o melhor intervalo entre a inseminação e a ovulação na P/IA de vacas Nelore lactantes submetidas ao protocolo de IATF utilizando sêmen sexado. Um total de 339 vacas Nelore apresentando 30 a 60 dias pós-parto da fazenda experimental da APTA, em Colina-SP foram utilizadas. No início do tratamento as fêmeas receberam um dispositivo intravaginal contendo 1g de progesterona (Sincrogest®,Ourofino Saúde Animal) e a aplicação i.m de 2mg de BE (Sincrodiol®, Ourofino). Após oito dias, o dispositivo foi removido e aplicados via i.m 0,25 mg de cloprostenol sódico (Sincrocio® , Ourofino) e 300UI de eCG (Folligon® , Intervet-Schering Plough). As vacas foram homogeneamente distribuídas para receberem IATF com sêmen sexado de um único touro da raça Angus (2.1milhões de espermatozóides por dose) às 36, 48 e 60 horas após a retirada dos dispositivos. O intervalo entre as inseminações e ovulações foi determinado e as análises realizadas comparando a taxa de prenhez entre os intervalos. Exames ultrassonográficos (7.5MHz, CTS-3300V, SIUI, China) foram realizados duas vezes ao dia, a partir da retirada do implante até 96 horas após e aos 30 pós IA para realização do diagnóstico de gestação. A P/IA foi definida como o número de fêmeas prenhes divididas pelo número de fêmeas inseminadas em cada intervalo. Os dados encontrados foram analisados usando o programa estatístico SAS. A taxa de ovulação após o protocolo foi de 92.0 % (312/339), o diâmetro do folículo ovulatório de 14,7 ± 2,3 mm e o intervalo entre retirada do dispositivo e ovulação de 71.8 ± 7.7 horas [48 horas (6.73%; 21/312), 60 horas (0.64%; 2/312), 72 horas (80.77%; 252/312), 84 horas (11.22%; 35/312), e 96 horas (0.64%; 2/312)]. A P/IA aumentou conforme se atrasou o momento da inseminação: 36 horas (5,8%; 5/86)c, 48 horas (20.8%; 27/130)b e 60 horas (30.9%; 38/123)a. A P/IA foi maior quando as inseminações foram realizadas próximas ao momento da ovulação (0 a 12 horas antes da ovulação = 37,9 %; 35/95) do que as realizadas entre 12,1 a 24 horas (19,4%; 21/108; P = 0,05) ou com mais de 24 horas (5,8%; 5/87; P = 0,0001) antes da ovulação sincronizada. Vacas recentemente ovuladas tiveram P/IA semelhante às realizadas próximo ao momento da ovulação (36,4%; 8/22; P = 0,95). Concluiu-se que a P/IA utilizando sêmen sexado é aumentada quando as inseminações são realizadas próximas a ovulação sincronizada. No experimento 2, de ressincronização, foram avaliadas, as taxas de serviço, concepção e prenhez em vacas previamente sincronizadas e inseminadas em tempo fixo. Foram formados dois grupos: observação de estro e IATF, utilizando na IA sêmen sexado e convencional. Os resultados para os grupos observação de estro e IATF foram, respectivamente: taxa de serviço [(63,5% (61/96); 100% (88/88)], taxa de concepção [(41% (25/61); 11,4% (10/88)], taxa de prenhez [(26% (25/96); 11,4% (10/88)]. Os resultados para os grupos observação de estro e IATF de acordo com o tipo de sêmen utilizado foram, respectivamente: sêmen convencional taxa de concepção [(43,3% (13/30); 14,9% (7/47))]; taxa de prenhez [(27,49% (13/61); 14,9% (7/47))]; sêmen sexado taxa de concepção [(38,7% (12/31); 7,3% (3/41))]; taxa de prenhez [(24,57% (12/61); 7,3% (3/41))]. / The identification of most appropriate moment to perform the timed artificial insemination (TAI) using sex-sorted semen following synchronization protocol can be important to improve the fertility of sex-sorted semen and increase the use sexed semen technology in commercial beef farms. The aim of this study was evaluated the better interval to perform the TAI relative to synchronized ovulation in suckled cows. A total of 339 suckled multiparous Nelore cows from an experimental farm (APTA), in Colina-SP, were evaluated in this study. The protocol started between 30 and 60 days post-partum. Cows received one synchronization protocol using an intravaginal device containing 1.0g of progesterone (Sincrogest®, Ouro Fino) plus an i.m. injection of 2.0mg of EB (Sincrodiol®, Ouro Fino). Eight days later, the device was removed and 0.25mg i.m. injection of cloprostenol sodium (Sincrocio®, Ouro Fino) and 300IU of eCG (Folligon®, Intervet-Shering Plough) were administered. Cows were homogenously assigned to receive TAI using sex-sorted semen from a single sire (2.1 millions of sperm cell per straw) at 36, 48 or 60 hours after device removal. The TAI to ovulation interval of synchronized cows was determined and the analysis was performed to compare the pregnancy for TAI performed at various intervals before ovulation using 12 hours time intervals. Ovarian ultrasonographic examinations (CTS-3300V, SIUI, China) were performed twice daily from day of the device removal to 96 hours afterwards, to evaluate ovarian follicular dynamics and interval from device removal to ovulation. All females were examined for pregnancy 30 days after AI. The data were analyzed using the SAS program.Incidence of ovulation after the estrous synchronization protocol was 92.0 % (312/339). Diameter of ovulatory follicle was 14.7 ± 2.3 mm and the interval between the P4 device removal and synchronized ovulation occurrence was 71.8 ± 7.7 hours. The distribution of the synchronized ovulation relative to the device removal was: 48 hours (6.73%; 21/312), 60 hours (0.64%; 2/312), 72 hours (80.77%; 252/312), 84 hours (11.22%; 35/312), and 96 hours (0.64%; 2/312). The pregnancy per artificial insemination (P/AI) was increased (P <0.001) when the TAI was delayed 36 hours (5.8%; 5/86)c, 48 hours (20.8%; 27/130)b and 60 hours (30.9%; 38/123)a. Higher P/AI was achieved on TAI performed closer to ovulation (0 to 12 hours before ovulation = 37.9 %; 35/95) than TAI performed on 12.1 to 24 hours (19.4%; 21/108; P = 0.05) or > 24 hours (5.8%; 5/87; P = 0.0001) before the synchronized ovulation. Recently ovulated cows had P/AI similar to those performed around the time of ovulation (36,4%; 8/22). In conclusion, P/AI is increased when the TAI using sex-sorted is performed closer to synchronized ovulation in suckled Nelore cows. In experiment 2, resynchronization, were assessed the service rates, conception and pregnancy in cows previously synchronized and timed AI. Two groups were formed: estrous detection and TAI, using in AI, sexed and unsexed semen. The results for groups of estrus detection and TAI were, respectively, service rate [(63.5% (61/96) 100% (88/88)], conception rate [(41% (25/61), 11.4% (10/88))], pregnancy rate [(26% (25/96), 11.4% (10/88))]. The results for groups of estrus detection and TAI according the type of semen used were: conventional semen conception rate [(43.3% (13/30), 14.9% (7 / 47))] ; pregnancy rate [(27.49% (13/61), 14.9% (7 / 47))]; sexed semen conception rate [(38.7% (12/31) 7.3% (3 / 41))]; pregnancy rate [(24.57% (12/ 61), 7.3% (3 / 41))].
344

Perfil das citocinas no prognóstico da mamite bovina após antibioticoterapia / Profile of cytokines in bovine mastitis prognosis after antibiotic therapy

Maria Gabriela Barbosa Lima 31 March 2014 (has links)
O presente estudo objetivou-se avaliar o perfil das citocinas como indicador prognóstico em diferentes protocolos de tratamento da mamite bovina. De um total de 130 vacas em lactação da raça holandesa foram selecionadas cinco vacas sem alteração ao exame do leite (C-), cinco vacas sem grumos no leite, mas com CMT positivo e 30 vacas com mamite clínica. Os animais com mamite clínica foram alocados em três grupos. O grupo G1 (n=10) recebeu tratamento com antibiótico sistêmico (enrofloxacina), enquanto o grupo G2 (n=10) recebeu somente antibiótico intramamário (sulfato de cefquinoma) e o grupo G3 (n=10) foi tratado com os dois princípios (enrofloxacina sistêmico e sulfato de cefquinoma intramamário). Os grupos controle foram formados respectivamente por animais negativos para as duas provas (C1; n=5), e negativos para a prova de fundo escuro e positivos para CMT (C2; n=5). Amostras de leite e sangue foram colhidas antes do tratamento (M0) e no segundo (M1), quinto (M2) e décimo segundo dia (M3) após o término do tratamento para serem submetidas a exame bacteriológico do leite, antibiograma do leite, dosagem de citocinas no leite e no sangue (IL-1, IL-2, IL-4, IL-6, IL-8, IL-10, TNF-&alpha; INF-&gamma;) e dosagem de imunoglobulinas no leite e no sangue (IgG1, IgG2, IgM e IgA). Foi verificada a normalidade da distribuição dos resultados, utilizando-se teste de Anderson-Darling. Para a avaliação das diferenças entre as médias dos resultados obtidos, foram realizados os testes de análise de variância ANOVA One-way (Unstacked) (para dados com distribuição normal) e Mann-Whitney (para dados que não apresentaram distribuição normal), sendo as análises consideradas significativas as que apresentaram P&le;0,05. Todos os animais do G3 apresentaram cura clínica e 80% cura bacteriológica nos momentos subsequentes ao tratamento (M1a M3). Ao se avaliar a resposta imunológica desse grupo, notou-se primeiramente o aumento de IL-6 sérico no M1 acompanhado de IgG1 e IgG2, os quais juntamente com o aumento de IL-4 e TNF-&alpha; perpetuaram a inflamação até o M2, enquanto que na glândula mamária já se iniciava a resolução da inflamação com o aumento de IL-10. Por outro lado, os animais do grupo G2 apresentaram cura clínica e bacteriológica no M1, porém esta não se manteve. Imunologicamente, após o tratamento, o perfil predominante desse grupo foi o Th2 com aumento de IgG1 e IL-4. Ao final do experimento, alguns animais do grupo G2 voltaram a manifestar a doença clinicamente, e tal fato foi acompanhado da diminuição das concentrações de IL-4, IgG1 e de IL-6 no leite. Nos animais do grupo G1 houve cura clínica não absoluta e 40% de cura bacteriológica no M3. Imunologicamente, observou-se altos níveis de IL-6 e IL-8 no leite durante todo o período de tratamento e diminuição de IgG2 sérico no M3 correlacionado negativamente com a IgG2 láctea, caracterizando uma resposta local tardia. Os resultados permitem inferir que o acompanhamento por mais de duas semanas da dinâmica da resposta imunológica depende da eficiência do protocolo antimicrobiana para se estabelecer um prognóstico. Além disso, a definição precoce da resposta imune pode ser dificultada pelo mais intenso tratamento antimicrobiano observado nos animais do tratamento combinado (G3) sendo insuficiente para debelar precocemente a infecção quando usado um tratamento antimicrobiano ineficiente. / The present study aimed to evaluate the cytokine profile as a prognostic in different treatment of bovine mastitis indicator. A total of 130 lactating cows of Holstein cows five without change to the examination of milk (C -), five cows in milk without lumps , but with positive CMT and 30 cows with clinical mastitis were selected . Animals with clinical mastitis were divided into three groups. The G1 (n = 10) received treatment with systemic antibiotics (enrofloxacin), while the G2 (n = 10) received only antibiotic intramammary (Cefquinome sulfate) and G3 (n = 10) group was treated with the two principles (systemic enrofloxacin and intramammary cefquinome sulfate). Control groups were formed respectively by the two negative tests (C1, n = 5) animals, and negative for evidence of dark and positive background for CMT (C2, n = 5). Milk and blood samples were collected before treatment (M0) and second (M1) , fifth (M2) and the twelfth day (M3) after completion of treatment to undergo bacteriological examination of milk , milk antibiogram, dosage cytokines in milk and blood (IL-1 , IL-2 , IL-4 , IL-6 , IL-8 , IL-10 , TNF- &alpha; IFN- &gamma; ) and serum immunoglobulin in milk and blood (IgG1 , IgG2 , IgM and IgA) . Normal distribution of the results was verified using the Anderson- Darling test. For the evaluation of differences between the means of the results obtained , tests of ANOVA One -way (unstacked) (for data with normal distribution) and Mann - Whitney test ( for data that were not normally distributed) were performed and the analyzes considered significant if P &le; 0.05 showed that . All G3 animals showed clinical cure and bacteriological cure in 80 % subsequent to treatment time (M1a M3). In evaluating the immune response of this group was noted primarily increased serum IL-6 in M1 together with IgG1 and IgG2, which together with the increased IL -4 and TNF- &alpha; to perpetuate inflammation M2 while mammary gland that has already started the resolution of inflammation with increased IL-10. On the other hand, the G2 group showed clinical and bacteriological cure in M1, but this was not maintained. Immunologically, after treatment, the predominant profile of this group was to increase the Th2 IgG1 and IL-4. At the end of the experiment, some animals from G2 again manifesting the disease clinically, and this fact was accompanied by decreased concentrations of IL - 4 , IgG1 and IL - 6 in milk. In animals of G1 there was no absolute clinical cure and bacteriological cure 40 % of the M3. Immunologically , it was observed high levels of IL-6 and IL-8 in the milk during the treatment period and a decrease in serum IgG2 M3 negatively correlated with milk IgG2 , featuring a late local response . The results may imply that monitoring for more than two weeks of the dynamics of the immune response depends on the efficiency of the antimicrobial protocol to establish a prognosis. In addition, the early definition of the immune response may be complicated by better antimicrobial treatment of animals observed in combined treatment (G3) being insufficient to overcome the infection early inefficient when used antimicrobials.
345

Manejo aversivo em bovinos leiteiros e efeitos no bem-estar , comportamento e aspectos produtivos / Aversive management in dairy cattle and effects on well-being, behavior and productive aspects

Peters, Mônica Daiana de Paula 06 March 2008 (has links)
Made available in DSpace on 2014-08-20T14:38:49Z (GMT). No. of bitstreams: 1 Dissertacao_ Monica_ Peters.pdf: 878946 bytes, checksum: b7413c46a3fb8157f851699145fb57ab (MD5) Previous issue date: 2008-03-06 / The human-animal interaction, determined by the type of management, is of fundamental importance in the dairy cattle production. And furthermore, the highest or lowest stress levels will be reached according to the nature of this particular interaction and so, consequently, the productivity and animal well-being. The study had the objective to evaluate the effects of aversive management on behavior, production and milk composition of cows. Thirty-two 60-96-month-old Holstein cows raised under extensive system were assessed. Behavior responses of reactivity (Re), defecation (De), urination (Mi), as well as the time spent in the milking parlour (TPO), duration of milking (TOR), milk production, chemical composition of the milk and somatic cell counting were registrated. Significative differences were found among managements regarding reactivity (P<0.0001), defecation (P=0.0208) e urination (P=0.0007). The cows aversively managed were the most reactive and showed the highest frequency of defecation in the milking parlour. However, cows submitted to aversive management had the lowest of urination. There was significative interaction (P<0.0001) among management and the days, regarding to TPO e TOR, demonstrating that in the end of the experiment the cows got used to the treatments. Looking at milk production, there was significative interaction (P=0.0062) between management and cow age; the aversive management negatively affected cow production with average age of 60 months. Nevertheless, there was no effect of the management on milk chemical composition and somatic cells counting. The aversive management alters the behavior of dairy cattle in the milking parlour, decreasing the well-being and reducing milk production of cows with an average age of 60 months. / A interação entre homem e animal, influenciada pelo tipo de manejo, é de fundamental importância na pecuária leiteira, pois de acordo com a sua natureza serão atingidos maiores ou menores níveis de estresse, com efeitos no bem-estar e na produtividade animal. O estudo teve como objetivo avaliar os efeitos do tipo de manejo: aversivo e não aversivo no comportamento, produção e composição do leite de vacas. Foram utilizadas 32 vacas holandesas, com idade entre 60 e 96 meses, criadas em sistema extensivo. Foram registradas respostas comportamentais de escore de reatividade (Re), freqüência de defecação (De) e micção (Mi), além do tempo de permanência na sala de ordenha (TPO), tempo de ordenha (TOR), produção de leite, composição química do leite e contagem de células somáticas. Foram encontradas diferenças significativas entre os tipos de manejos, com relação à reatividade (P<0,0001), freqüência de defecação (P=0,0208) e de micção (P=0,0007). Vacas manejadas aversivamente foram mais reativas e apresentaram maior freqüência de defecação na sala de ordenha. No entanto, vacas submetidas ao manejo aversivo apresentaram menor freqüência de micção. Houve interação significativa (P<0,0001) entre os tipos de manejos e os dias com relação ao TPO e TOR. No período final do experimento, as vacas se habituaram aos tratamentos e deixaram de responder ao estímulo. Na produção de leite houve interação significativa (P=0,0062) entre manejo e idade das vacas, onde o manejo aversivo afetou negativamente a produção de vacas com idade média de 60 meses. Entretanto, não houve efeito dos tipos de manejo sobre a composição química do leite e contagem de células somáticas. Concluiu-se que o manejo aversivo altera o comportamento das vacas na ordenha, reduzindo o bem-estar animal, com diminuição da produção de leite de vacas com idade média de 60 meses.
346

Efeitos da administração de Butafosfan e Cianocobalamina após o parto, sobre parâmetros metabólicos e produtivos de vacas leiteiras / Effects of administration of Butafosfan and Cyanocobalamin postpartum on metabolic parameters and production of dairy cows

Pereira, Rubens Alves 26 February 2010 (has links)
Made available in DSpace on 2014-08-20T13:32:54Z (GMT). No. of bitstreams: 1 dissertacao_rubens_alves_pereira.pdf: 581091 bytes, checksum: 129866c31d5af8b07ef3e33c3e342067 (MD5) Previous issue date: 2010-02-26 / The aim of this study was to determine the effects of intramuscular injection of Butaphosphan and Cyanocobalamin on the parameters of energy metabolism, protein, enzyme, mineral and livestock of dairy cows in the postpartum period. We used 52 animals of the Holstein breed. The experimental period ranged from birth to 150 days of lactation. These cows were divided into 3 groups: BC10 (n=18), who received 5 doses of 10mL of solution of Butaphosphan+Cyanocobalamin, BC20 (n=18), who received 5 doses of 20mL of Butaphosphan+Cyanocobalamin; and CG (n=16), used as a control group received 5 doses of 10mL of saline (NaCl 0.9%). Administrations were performed with an interval of 5 days, intramuscularly, and blood samples every 5 days. Evaluations were performed on body condition score (BCS) and productive performance during the postpartum period and measurements of metabolic parameters such as blood glucose, nonesterified fatty acid (NEFA), urea, calcium (Ca), phosphorus (P), magnesium (Mg), aspartate aminotransferase (AST), gamma-glutamyltransferase (GGT) and ketone (CC) in urine. The measurements of blood glucose were not changed during the study period. The blood levels of NEFA were higher (P<0.05) for the GC compared to BC10 and BC20, which also differed (P<0.05). Urea levels did not differ between groups (P>0.05). There were no differences (P>0.05) in the metabolites Ca, P, Ca: P, Mg and CC in the urine. The same finding was common to liver enzymes, AST and GGT. The animals in groups BC10 and BC20 had a milk production higher than the GC (P<0.05), but did not differ (P>0.05). The analysis of milk components were similar (P>0.05) between groups. These results demonstrated that the use of Butaphosphan and Cyanocobalamin in dairy cows during the postpartum period, is effective in alleviating the negative energy balance and improving the productive performance, without causing liver overload. / O objetivo deste estudo foi determinar os efeitos da administração de Butafosfan e Cianocobalamina sobre os parâmetros do metabolismo energético, protéico, enzimático, mineral, produção e composição do leite de vacas leiteiras durante o período pós-parto. Foram utilizados no experimento 52 vacas da raça Holandês, avaliadas do parto até 150 dias de lactação. Estas vacas foram divididas em 3 grupos experimentais: o BC10 (n=18), que recebeu 5 doses de 10mL de solução aquosa de Butafosfan+Cianocobalamina; o BC20 (n=18), que recebeu 5 doses de 20mL de solução aquosa de Butafosfan+Cianocobalamina; e o grupo controle (GC n=16), que recebeu 5 doses de 10mL de solução fisiológica (NaCl 0,9%). Foram realizadas administrações logo após o parto, com intervalo de 5 dias, por via intramuscular. Foi coletado sangue a cada 15 dias a partir do terceiro dia pós-parto para a determinação dos níveis de glicose, ácidos graxos não esterificados (NEFA), β-hidroxibutirato (BHBA), uréia, cálcio (Ca), fósforo (P), magnésio (Mg), aspartato aminotransferase (AST) e gama-glutamiltransferase (GGT). Foi coletada urina a cada 15 dias a partir do terceiro dia pós-parto para a determinação de corpos cetônicos (CC). Avaliou-se o escore de condição corporal (ECC) e produção leiteira. Todos os grupos diferiram entre si quanto aos níveis de NEFA, sendo maiores no GC. Os grupos BC10 e BC20 diferiram entre si, sendo superiores no BC10. Os níveis de BHBA foram maiores no GC em relação ao BC10 e BC20, os quais não diferiram entre si. Quanto às avaliações zootécnicas, os grupos BC10 e BC20 apresentaram uma produção leiteira maior que o GC, porém não diferiram entre si. As concentrações dos componentes do leite não foram alteradas até 150 dias da lactação. Estes resultados demonstraram que a solução de Butafosfan e Cianocobalamina, administradas em vacas leiteiras após o parto, reduz o balanço energético negativo e aumenta a produção de leite, sem sobrecarregas o fígado.
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Dynamiques individuelles et interactions entre santé mammaire, déséquilibres nutritionnels et l'établissement de la gestation chez la vache laitière / Individual dynamics and interactions of udder health, nutritional disorders and conception establishment in dairy cows

Albaaj, Ahmad 04 July 2017 (has links)
La fertilité des vaches laitières s’est beaucoup dégradée au cours des dernières décennies, tant à l’échelle nationale qu’internationale. L’objectif poursuivi est d’apporter un éclairage épidémiologique sur les relations dynamiques entre la conception (réussite à l’insémination artificielle ; IA), les mammites subcliniques et les déséquilibres métabolico-nutritionnels que sont la cétose subclinique et les déséquilibres azotés de la ration. Un premier chapitre bibliographique dresse l’état de l’art des liens entre performances de reproduction et (i) mammites, (ii) cétose subclinique et (iii) excès de protéines dégradables, en identifiant clairement les interactions et associations croisées entre ces différents composants, et en quantifiant autant que possible ces liens. Les trois parties suivantes mobilisent des données exhaustives du contrôle laitier français sur la période 2008-2012, qui ont été confrontées aux données d’IA. La variable d’intérêt retenue est la conception après IA, soit pour la première IA (IA1) ou pour toutes les IA. Les variations des concentrations de cellules somatiques (CCS) autour de l’IA ont été utilisées pour décrire la dynamique des mammites subcliniques autour de l’IA, selon 4 classes (Bas-Bas, Bas-Haut, Haut-Bas et Haut-Haut) et pour différents seuils de CCS. Le statut de cétose subclinique a été évalué grâce aux taux butyreux et protéique du lait. Les concentrations d’urée du lait sont utilisées pour caractériser les déséquilibres azotés. Le second chapitre propose une description succincte des résultats de production et de reproduction des troupeaux bovins laitiers français sur la période d’étude. Le troisième chapitre focalise sur l’interaction entre les CCS et la cétose subclinique dans un modèle de régression de Poisson expliquant la conception. Les chances de conception à l’IA1 sont réduites de 14% (Risque relatif = 0,86 [IC 95%=0,85–0,87]) pour les groupes Bas-Haut et Haut-Haut, comparé au groupe Bas-Bas, et de 3 à 17 %, selon les définitions retenues, lors de cétose subclinique comparé à son absence. Les résultats identifient et quantifient clairement l’interaction entre la cétose subclinique et les mammites subcliniques dans leur association avec la conception : la baisse de la conception est jusqu’à 2 fois supérieure lors de la présence simultanée d’une augmentation des CCS et d’une cétose subclinique par rapport à la situation où il y a seulement augmentation des CCS. Le quatrième chapitre, mobilisant des méthodes proches de celles du chapitre précédent, montre que la baisse de la concentration d’urée dans le lait autour de l’IA (en dessous de 150 mg/kg, 2,6 mmol/L) est associée à une baisse de la conception de 5 à 9% (Risque relatif = 0.91 (IC95%=0,87-0,96)]) par rapport à des concentrations d’urée du lait qui restent stables (250 - 450 mg/kg ou 4,3-7,7 mmol/L). Ceci révèle l’importance de la stabilité du métabolisme azoté autour de la conception, y compris pour des variations d’urée du lait ou du sang à la baisse, alors que seule la hausse de la concentration d’urée était identifiée comme un facteur de risque de dégradation des résultats de reproduction jusqu’alors. La dernière partie permet de mettre en perspective ces éléments originaux. Une des principales limites de ces travaux est la définition imprécise de la cétose subclinique réalisée à partir des taux du lait ; les résultats actuels bénéficieraient d’une actualisation avec un indicateur plus précis de ce trouble. Ces résultats soutiennent qu’une inflammation locale peut affecter la réponse de l’ensemble de l’organisme et altérer les fonctions d'autres organes dans les semaines qui suivent son apparition. Ils illustrent la complexité et les interactions entre les différents troubles chez un même animal. Par ailleurs, maintenir des concentrations basses de l’urée est légèrement pénalisant pour la conception, et ne garantit pas de meilleurs résultats de reproduction. / Reproductive performances of dairy cows are recognized as a key parameter for the profitability of dairy farms, but they are getting worse continuously in many countries during the last decades. Infectious and nutritional disorders are possible contributors to these changes. Mammary infection, nitrogen imbalance and metabolic disorders have been reported to be negatively associated with conception, but their interactions and dynamics are not fully understood. The objective of the present work is to better describe the relationship between fertility, udder health, subclinical ketosis (SCK) and nitrogen imbalance accounting for the temporal variations of these events and their interactions. The first section reviews the link between reproductive performances and (i) mastitis, (ii) metabolic disorders and (iii) nitrogen imbalance in dairy cows in order to clarify the complex interaction among these events. The three other sections are based on exhaustive data from the national French dairy milk improvement system and data on the artificial inseminations (AI) from 2008 to 2012. Fertility was explained as conception at the first (AI1) or at all AI. The udder health status was evaluated through the somatic cells counts (SCC). Several proxies based on the milk fat and protein contents were proposed to define SCK. Milk urea concentration was used to investigate the exposure to nitrogen imbalance. The second section aims to describe the actual situation of milk production and reproduction in French dairy herds. The third section focuses on the interaction between SCC and SCK and their association with conception. On average, the risk of conception at AI1 was 14% lower when the SCC increased or remained high within 40 days before and after AI (Relative risk [and 95% CI] = 0.86 [0.85–0.87]), compared to low SCC before and after AI. The reduction in conception rate associated with SCK (fat and protein contents changes) varied from 3% to 17% depending on the SCK proxy used. Including the interaction term SCC*SCK clearly showed that the association of increased SCC around AI with conception was modified by the presence of SCK. A cow that already has SCK and experiences an increase in SCC around or after AI exhibits up to 2 times further decrease in conception, compared with a cow with a high SCC and no SCK. The fourth section, using similar methods as the previous one, shows that low milk urea concentrations after AI are negatively associated with conception. Cows with a low urea (< 150 mg/kg, 2.6 mM) after AI have a reduced conception (Relative risk RR [and 95% CI] = 0.96 [0.94–0.99]) compared to cows with intermediate urea (250-450 mg/kg, 4.3 - 7.7 mM) after AI. Furthermore, the risk of conception was 5 to 9% lower (relative risk [and 95% CI] = 0.91 [0.87–0.96]) when urea concentrations decrease from intermediate before to low after AI, compared with cows with constant intermediate urea values. This work revealed that a decrease in urea from intermediate (before AI) to low (after AI) is a risk factor for conception failure in addition to the previously known risk factor that is nitrogen excess. The final section aims to highlight the perspectives of these results. The definition of SCK used in this work was identified as the main limitation and the present results would benefit from an update with a better indicator of this disorder. The present work supports that a local inflammation may affect the entire body response and alters the functions of other organs like those of the reproductive tract. Furthermore, maintaining low urea concentrations does not provide any particular advantage and might be negatively associated with conception.
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Terminorientierte Besamung nach Presynch- oder Ovsynch-Behandlung sowie ein Vergleich verschiedener Methoden der Trächtigkeitsfeststellung bei Milchkühen

Marthold, Daniela 05 November 2012 (has links)
No description available.
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Improving the value of cull cows through antemortem management practices and postmortem enhancement technologies

Hutchison, Shanna January 1900 (has links)
Doctor of Philosophy / Department of Animal Sciences and Industry / John A. Unruh / Sixty cows were utilized to investigate the use of zilpaterol, implanting, and concentrate feeding on performance, carcass traits, subprimal yield, steak retail display, and meat palatability of cows fed for 70 d. The 5 treatments were: 1) grass-fed on pasture (Grass); 2) concentrate-fed (C); 3) concentrate-fed and implanted (CI) with a trenbolone acetate/estradiol implant, DE); 4) concentrate-fed and fed zilpaterol beginning on d 38 of the feeding period (CZ); and 5) concentrate-fed, implanted and fed zilpaterol (CIZ). Hot carcass weights and dressing percentages were higher (P < 0.05) for all concentrate-fed cows than grass-fed cows. The CIZ cows had the largest and grass-fed cows the smallest longissimus muscle (LM) areas. Total subprimal weights were lightest for cuts from the grass-fed cows; and CIZ cows had greater weights than those from C cows. Sensory panelists found LM steaks from C and grass-fed cows were more tender than steaks from CZ and CIZ cows; and steaks from CI cows were more tender than steaks from CIZ cows. However, no tenderness differences were observed among treatments for knuckle (KN) steaks. In another study, carcasses from 31 fed cows and 24 fed steers were used to investigate the effects of aging (7 or 28 d) on LM retail display; aging and enhancement (blade tenderization and enhancement solution injection) on LM tenderness; and aging on enhanced KN, top blade, and top sirloin steaks. Steaks (LM) aged 7 d had less discoloration and were more color stable than steaks aged for 28 d. A sensory panel found enhanced-cow LM steaks were more tender than non-enhanced steaks; and aging for 28 d improved tenderness compared to 7 d aging for non-enhanced steaks only. Aging for 28 d compared to 7 d improved Warner-Bratzler shear (more tender) for enhanced cow top sirloin, steer top sirloin, and steer top blade steaks. Feeding cull cows a concentrate diet improved lean meat yields. When feeding a concentrate diet a combination of an implant and feeding zilpaterol can further increase lean meat yields. Enhancement provides an opportunity to improve tenderness of steaks from fed cows and steers.
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Effects of prepartum whole cottonseed or whole raw soybean supplementation on response to timed artificial insemination in suckled mature beef cows following ovulation synchronization

Thomas, Melissa Deann January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / K C Olson / Prepartum fat supplementation has been associated with improved reproductive performance by cows managed for AI. Our objective was to evaluate the effects of prepartum supplementation with whole cottonseed or whole raw soybeans on response to ovulation synchronization and timed artificial insemination in mature beef cows. Cows (n = 188; average initial BW = 579 [plus or minus] 54 kg) were stratified by BCS and BW and assigned to 3 supplementation treatments: whole raw soybeans (21.6 % fat, 38.6% CP), whole fuzzy cottonseed (21.7% fat, 21.1% CP), or a 50:50 mixture of ground corn and soybean meal (2.6% fat, 30.6% CP). Supplements were fed at 1.8 kg per animal daily for 45 d before the first projected calving date (April 1). Supplementation was continued until each cow calved; thereafter, all cows received the control supplement until May 1. Ovulation was synchronized using the CoSynch + CIDR protocol and cows were bred via AI on June 21. Eleven d after AI, cows were exposed for natural service breeding for 50 d. Conception to AI was assessed 33 d after AI. Overall conception was assessed and conception to AI reaffirmed 126 d after AI. Body weight of cows fed control or oilseed supplements was similar (P > 0.3) at calving, initiation of ovulation synchronization, and at the end of the breeding season. Cottonseed-supplemented cows lost more BW and more BCS (P < 0.03) from the beginning of the trial to calving than those fed soybeans. Proportion of cycling cows was similar (P = 0.57) between treatments. Pregnancy to timed AI and final pregnancy rates were similar (P > 0.75) between control and oilseed-supplemented cows. Conversely, supplementation with cottonseed was associated with increased AI conception (P = 0.08; 54 and 39%, for cottonseed and soybeans, respectively) and greater final pregnancy rate compared to soybean-fed cows (P = 0.03; 100 and 93% for cottonseed and soybeans, respectively). Calf birth weights and calf weights at the end of the breeding season were similar (P > 0.24) between treatments. Effects of cottonseed and soybean supplementation on response to ovulation synchronization and timed AI by beef cows warrant further study.

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