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Search Results: 1 - 10 of 41276 matches for " Paulo Fernando;Coldebella "
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Métodos de conserva??o de amostras de leite para determina??o da contagem bacteriana total por citometria de fluxo
Cassoli, Laerte Dagher;Machado, Paulo Fernando;Coldebella, Arlei;
Revista Brasileira de Zootecnia , 2010, DOI: 10.1590/S1516-35982010000200029
Abstract: the objective of this study was to evaluate the effect of storage temperature and sample age on the total bacterial count (tbc) of milk samples preserved with azidiol to verify whether a single sample could be used to perform regulatory milk analysis under the normative instruction 51 (in-51). three hundred and twenty milk aliquots were used collected from an expansion tank to assess three storage temperatures (0 oc - frozen: 7 oc - refrigerated, and 24 oc - room temperature), three types of conservation (bronopol, azidiol and no preservative) and four sample ages (1, 3, 5, and 7 days). for the total bacteria count, refrigerated control samples, with azidiol and one day old samples, and for composition and somatic cell count (scc), the controls were defined as one day old refrigerated samples containing bronopol. samples conserved with bronopol presented lower total bacteria count than the control regardless of storage temperature and sample age. milk samples conserved with azidiol and stored refrigerated presented lower scc, regardless of age, compared to refrigerated samples conserved with bronopol. the fat and lactose contents decreased after the fifth day. two samples had to be collected: one for scc determination and composition containing bronopol and another for the total bacteria count containing azidiol. milk samples used for total bacteria count can be tested up to 7 days if they are kept at 7 oc with the addition of azidiol.
Contagem de células somáticas e produ o de leite em vacas holandesas de alta produ o
Coldebella Arlei,Machado Paulo Fernando,Demétrio Clarice Garcia Borges,Ribeiro Júnior Paulo Justiniano
Pesquisa Agropecuária Brasileira , 2003,
Abstract: A mastite bovina pode ser clínica, com sinais visíveis, e subclínica, diagnosticada pela contagem das células somáticas. As perdas econ micas causadas pela mastite subclínica devem ser quantificadas para atender à demanda nacional de produtos lácteos. O objetivo deste trabalho foi verificar se as perdas na produ o de leite, pelo aumento do número de células somáticas, s o proporcionais ou independentes do nível de produ o. Foram utilizadas 7.756 observa es, colhidas mensalmente de um único rebanho, de setembro de 2000 a junho de 2002. A curva de lacta o foi modelada pela fun o gama incompleta, e os efeitos de ordem de lacta o, época do parto, ocorrência de doen as no periparto e escore de condi o corporal ao parto também foram considerados. A contagem de células somáticas foi incluída nesse modelo como fator multiplicativo, representando perdas relativas, e como fator aditivo, representando perdas absolutas. A escolha do melhor modelo foi baseada no critério de informa o de Schwarz (BIC). As perdas s o absolutas, evidentes a partir de 14.270 células/mL e para cada aumento de uma unidade na escala do logaritmo natural a partir desse valor, estimam-se perdas de 184 e 869 g/dia para vacas primíparas e multíparas, respectivamente.
Valida o de modelos de predi o de nitrogênio uréico no leite, estimando-se o consumo individual pelo consumo do rebanho = Validation of models to predict milk urea nitrogen concentrations, using herd intake to estimate individual dry matter intake
Paula Marques Meyer,Paulo Fernando Machado,Arlei Coldebella,Laerte Dagher Cassoli
Acta Scientiarum : Animal Sciences , 2006,
Abstract: O objetivo deste trabalho foi validar modelos de predi o de nitrogênio uréico no leite (NUL), visando contribuir para avalia o nutricional de dietas de vacas. Foram utilizadas 8.833 observa es de vacas holandesas de um rebanho comercial. A produ o de leite, o pesovivo, o número de dias em lacta o e o número de lacta es foram coletados no dia da amostragem do leite. Amostras de leite foram coletadas mensalmente para determina o da sua composi o. Para a avalia o dos 3 modelos, foram medidas acurácia, precis o e robustez. O modelo 3, apesar de mais acurado (viés=-0,21 mg/dL), foi menos preciso (erro residual=5,24 mg/dL) que o modelo 2 (viés=-1,72 e erro residual=4,90 mg/dL), enquanto o modelo 1 foi o menos acurado (viés=2,93 mg/dL) e o menos preciso (erro residual=5,99 mg/dL). Houve falta de robustez para os 3 modelos. Os três modelos de predi o de NUL diferiram entre si quanto à acurácia, precis o e robustez. The objective of this study was to validate prediction models for milk urea nitrogen (MUN), aiming at evaluating utilization efficiency of diets for dairy cows. Data (8,833 observations) from Holstein cows were used. Milk production, body weight, days in milk and lactation number were collected on the milk sampling days. Milk samples were collected monthly for composition analysis. In order to evaluate the three models, accuracy, precision and robustness were tested. Despite being more accurate (mean bias=-0.21 mg/dL), model 3 was less precise (residual error=5.24 mg/dL) than model 2 (mean bias=-1.72 and residual error=4.90 mg/dL), while model 1 was the least accurate (mean bias=2.93 mg/dL) and the least precise (residual error=5.99 mg/dL). There was lack of robustness for the three models. Models for predicting MUN differ among themselves with regard to accuracy, precision and robustness.
Fatores de risco associados a falhas de concep o ao primeiro servi o em vacas leiteiras de alta produ o = Risk factors associated with failure of first breeding pregnancy in dairy cows
Carlos Humberto Corassin,Paulo Fernando Machado,Arlei Coldebella,Sérgio Soriano
Acta Scientiarum : Animal Sciences , 2009,
Abstract: Este estudo investigou os fatores de riscos para falhas na concep o ao primeiro servi o pós-parto (CPS). Vacas Holandesas (n = 427) tiveram seu desempenho reprodutivo, sanitário e nutricional acompanhados do período pré-parto até a CPS, sendo registrados as ocorrências de doen as e os escores de condi o corporal (ECC), no pré e pós-parto, e as composi es do leite. Análises de regress o logística foram utilizadas para se modelar os fatores de risco e na associa o entre os diversos riscos para sucesso ou falha naCPS. As variáveis ordenadas foram: número da lacta o, época do ano ao primeiro servi o, ocorrência de doen as no periparto (DP), rela o entre as porcentagens de gordura e proteína do leite (RGP) e altera es no ECC. Animais primíparos apresentaram maior chance de sucesso ao primeiro servi o do que os multíparos. Vacas cobertas no inverno apresentaram, aproximadamente, cinco vezes mais chances de CPS do que as cobertas no ver o. Animais com DP tiveram menor sucesso de concep o que os animais sadios. Vacas com melhor condi o ruminal, determinada pela RGP, tiveram melhor concep o do que vacas com RGP reduzida. O ECC, adequado nas diferentes fases produtivas, demonstrou ser importante ferramenta para se identificar vacas com risco de insucesso na CPS. This study investigated the risk factors for failure in the conception to the first postparturition service (CFS). Holstein cows (n = 427) had their reproductive, health and nutritional status monitored from the period of pre-parturition to the CFS. Occurrence of diseases and body condition scores (BCS), at pre- and post-parturition, as well as milk composition, were recorded. Logistic regression models were used to isolate the risk factors and associations among the several risks for success or failure in CFS. The variables studied were lactation number, season of the first service, occurrence of peripartum diseases (PD), ratio of fat and protein of milk (RFP) and alterations in BCS. Primiparous cows presented larger success chance for first service than multiparous specimens. The inseminated cows in the winter presented, approximately, five times more chances of CFS than the cows inseminated in the summer. Cows that presented PD had smaller conception success than healthy cows. The animals that presented a better ruminal condition, determined by RFP, had better conception than the animals with reduced RFP. BCS, appropriate in the different productive phases, proved to be an important tool to identify cowswith failure risk in the CFS.
Importance of calving diseases and risk factors on milk production of Holsteins cows Importancia das desordens do periparto e seus fatores de risco sobre a produ o de leite de vacas Holandesas
Carlos Humberto Corassin,Paulo Fernando Machado,Arlei Coldebella,Laerte Dagher Cassoli
Semina : Ciências Agrárias , 2011,
Abstract: This correlational study investigated the effects of the peripartum health disorders and your respective risk factors about the milk production, in the peak and to the 305 days in lactation. Holsteins cows (n = 522) of a commercial herd of the State of S o Paulo, had your health and nutritional status accompanied since the beginning of the period pre-calving to the end of the lactation. Occurrence of diseases, score of body condition (at the dry off and calving), daily milk productions and milk compositions, were recorded. For statistical analysis of the data, the logistics regression and the analysis of multiple regression were used. The obtained results demonstrated that the diseases of the peripartum and your risk factors affected the milk production with different effects in function of the lactation numbers, demanding this way, larger care with the prophylactic measures to avoid the diseases, and to maximize the production of milk and the reproduction of the animals. Este estudo correlacional investigou os efeitos das ocorrências sanitárias do periparto e seus respectivos fatores de risco sobre a produ o de leite, no pico e aos 305 dias em lacta o. Vacas Holandesas (n = 522) de um rebanho comercial do Estado de S o Paulo tiveram seu desempenho sanitário e nutricional acompanhados desde o início do período pré-parto até o final da lacta o. A ocorrência de doen as, os escores de condi o corporal (no pré-parto e parto), as produ es de leite e as composi es do leite foram registradas. Para análise estatística dos dados, foram utilizadas a regress o logística e a análise de regress o múltipla. Os resultados obtidos demonstraram que as doen as do periparto e seus fatores de risco afetaram a produ o de leite com efeitos diferentes em fun o do número de lacta es, exigindo desta maneira maior cuidado com ado o de medidas profiláticas para se evitar as doen as e maximizar a produ o de leite dos animais.
DETERMINA O DO PERFIL FíSICO-QUíMICO DE AMOSTRAS DE LEITE DE BúFALAS, POR MEIO DE ANALISADORES AUTOMATIZADOS
Karyne Oliveira Coelho,Paulo Fernando Machado,Arlei Coldebella,Laerte Dagher Cassoli
Ciência Animal Brasileira , 2006,
Abstract: No período de janeiro de 2001 a junho de 2002, foram realizadas análises físico-químicas em amostras de leite de búfalas, de dezenove rebanhos do estado de S o Paulo. Procedeu-se à determina o da contagem de células somáticas (CCS) e de componentes: gordura (G), proteína(P), lactose (L) e sólidos totais (ST) em 6.564 amostras. Os valores médios e coeficientes de varia o foram, respectivamente: 6,81% e 22,60%, para G; 4,20% e 11,73%, para P;5,02% e 7,09%, para L; 17,23% e 9,53%, para ST e 137 mil células/mL e 378,15% para CCS. Esses valores poder o contribuir para o estabelecimento e o aperfei oamento de normas para controlar a qualidade de leite cru de búfalas. PALAVRAS-CHAVE: Búfalos, composi o do leite, qualidade do leite.
Validation of models for predicting milk urea nitrogen concentrations, estimating dry matter intake by the NRC (2001)
Meyer, Paula Marques;Machado, Paulo Fernando;Coldebella, Arlei;Cassoli, Laerte Dagher;Coelho, Karyne Oliveira;Rodrigues, Paulo Henrique Mazza;
Revista Brasileira de Zootecnia , 2012, DOI: 10.1590/S1516-35982012000500026
Abstract: the objective of this study was to validate three different models for predicting milk urea nitrogen using field conditions, attempting to evaluate the nutritional adequacy diets for dairy cows and prediction of nitrogen excreted to the environment. observations (4,749) from 855 cows were used. milk yield, body weight (bw), days in milk and parity were recorded on the milk sampling days. milk was sampled monthly, for analysis of milk urea nitrogen (mun), fat, protein, lactose and total solids concentration and somatic cells count. individual dry matter intake was estimated using the nrc (2001). the three models studied were derived from a first one to predict urinary nitrogen (un). model 1 was mun = un/12.54, model 2 was mun = un/17.6 and model 3 was mun = un/(0.0259 × bw), adjusted by body weight effect. to evaluate models, they were tested for accuracy, precision and robustness. despite being more accurate (mean bias = 0.94 mg/dl), model 2 was less precise (residual error = 4.50 mg/dl) than model 3 (mean bias = 1.41 and residual error = 4.11 mg/dl), while model 1 was the least accurate (mean bias = 6.94 mg/dl) and the least precise (residual error = 5.40 mg/dl). they were not robust, because they were influenced by almost all the variables studied. the three models for predicting milk urea nitrogen were different with respect to accuracy, precision and robustness.
Fatores n?o-nutricionais e concentra??o de nitrogênio uréico no leite de vacas da ra?a Holandesa
Meyer, Paula Marques;Machado, Paulo Fernando;Coldebella, Arlei;Cassoli, Laerte Dagher;Coelho, Karyne Oliveira;Rodrigues, Paulo Henrique Mazza;
Revista Brasileira de Zootecnia , 2006, DOI: 10.1590/S1516-35982006000400024
Abstract: the objective of this study was to evaluate the association of non-dietary factors on the concentration of milk urea nitrogen (mun), as an indicator of efficiency of nutrient utilization by lactating dairy cows. a dataset containing 7,006 observations from 855 lactating holstein cows were used. milk yield, body weight, days in milk and number of lactation were collected on the milk sampling days. monthly samples of milk were collected to determine contents of milk fat, protein, lactose, total solids, mun and somatic cells count (scc). yield of milk components (fat, protein, lactose and total solids) as well as 4% fat-corrected milk (fcm) were also used in the study. regression analyses of mun, as the dependent variable, on fcm, scc and content and yield of milk components were done to analyze the data. mean mun and milk yield averaged 13.3 mg/dl and 35.8 kg/day, respectively. milk contents of fat, protein, lactose and total solids as well as scc (natural logarithm transformed) were negatively associated with mun while the opposite was observed for yields of milk lactose and total solids and milk production. yields of milk fat and milk protein (kg), fcm, days in milk and number of lactation all were correlated with mun, however there was lack of fit for the linear equation. no significant correlations between mun and body weight and mun and fat:protein ratio were observed. among the non-dietary factors, milk yield and milk protein concentration correlated most with mun.
Desempenho de frangos de corte alimentados com ingrediente de alta digestibilidade nas fases de cria??o pré-inicial e inicial
Dallmann, Henrique Müller;Avila, Valdir Silveira de;Brum, Paulo Antonio Rabenschlag de;Costa, Paulo Tabajara Chaves;Coldebella, Arlei;Dallmann, Paulo Roberto;Maier, Jo?o Carlos;Rutz, Fernando;
Pesquisa Agropecuária Brasileira , 2010, DOI: 10.1590/S0100-204X2010000900002
Abstract: the objective of this work was to evaluate the effect of the diet, with the inclusion of an energetic-protein nucleus (epn) composed of highly digestible ingredients, on the productive performance and carcass traits of broiler chicks. the nucleus was composed by degummed soybean oil, pre-gelatinized corn, twice-processed soybean, mannanoligosaccharides and peptides. the total of 864 male agross 508 broiler, with one day of age, were weighed individually and distributed in a randomized block design. treatments consisted of: t1, control, 0% epn; t2, 7% epn (1-7 days) and 3.5% epn (8-21 days); t3, 14% epn (1-7 days) and 7% epn (8-21 days); and t4, 21% epn (1-7 days) and 10.5% epn (8-21 days of age). at 21 days of age, body weight, weight gain, average feed intake, feed conversion and carcass and cut-ups yield were not significantly affected by treatments. the epn inclusion in the diets did not influence the performance, carcass traits and cut-ups of broilers.
Contagem de células somáticas e produ??o de leite em vacas holandesas de alta produ??o
Coldebella, Arlei;Machado, Paulo Fernando;Demétrio, Clarice Garcia Borges;Ribeiro Júnior, Paulo Justiniano;Corassin, Carlos Humberto;Meyer, Paula Marques;Cassoli, Laerte Dagher;
Pesquisa Agropecuária Brasileira , 2003, DOI: 10.1590/S0100-204X2003001200012
Abstract: the goal of this paper was to evaluate if losses in milk yield due to increase in somatic cells count are proportional or independent of the level of production. a total of 7,756 observations, monthly collected from a single herd from september/2000 up to june/2002, were used. the lactation curve was modeled by the incomplete gamma function, considering the effects of lactation order, calving season, peripartum disorder incidence and body condition score at calving. somatic cells count was added to the model as a multiplicative factor, representing relative losses, and as an additive factor, representing absolute losses. the best model was chosen based on the information criteria of schwarz (bic). the losses are absolute, becoming evident from 14,270 cells/ml, and they are 184 and 869 g/day for each increase of one unit in the natural logarithm scale, starting from that somatic cells count, for primiparous and multiparous cows, respectively.
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