Aplicação de modelos de regressão aleatória utilizando diferentes estruturas de dados

A total of 3.035 lactations of Holstein cows from four farms in the Southeast, to check the influence of data structure of milk yield on the genetic parameters. Four dataset with different structures were tested, weekly controls (CW) with 122.842 controls, monthly controls (CM) 30.883, bimonthly controls (CB) with 15,837 and quarterly controls (CQ) with 12,702. The random regression model was used and was considered as random additive genetic and permanent environment effects, fixed effects of the contemporary groups (herd-year-month of test-day) and age of cow (linear and quadratic effects). Heritability estimates showed similar trends among the data files analyzed, with the greatest similarity between dataset CS, CM and CB. The dataset submitted all the CB estimates of genetic parameters analyzed with the same trend and similar magnitude to the CS and CM dataset, allowing the claim that there was no influence of the data structure on estimates of covariance components for the dataset CS, CM and CB. Thus, milk recording could be accomplished in a CB structure.

Genetic heterogeneity of Escherichia coli isolated from pasteurized milk in State of Paraná, Brazil

Food contamination caused by enteric pathogens is a major cause of diarrheal disease worldwide, resulting in high morbidity and mortality and significant economic losses. Bacteria are important agents of foodborne diseases, particularly diarrheagenic Escherichia coli. The present study assessed the genetic diversity and antimicrobial resistance of E. coli isolates from pasteurized milk processed in 21 dairies in northwestern State of Parana, Brazil. The 95 E. coli isolates were subjected to antimicrobial susceptibility testing according to the recommendations of the Clinical and Laboratory Standards Institute and assessed genotypically by Enterobacterial Repetitive Intergenic Consensus-Polymerase Chain Reaction (ERIC-PCR). The highest rate of resistance was observed for cephalothin (55.78%). ERIC-PCR revealed high genetic diversity, clustering the 95 bacterial isolates into 90 different genotypic patterns. These results showed a heterogeneous population of E. coli in milk samples produced in the northwestern region of Parana and the need for good manufacturing practices throughout the processing of pasteurized milk to reduce the risk of foodborne illnesses.

Fluoride concentrations of milk, infant formulae, and soy-based products commercially available in Brazil

To assess the fluoride (F) content in commercially available milk formulae in Brazil and to estimate the F intake in children from this source in the first year of life. Samples of cow's milk (n = 51), infant formulae (n = 15), powdered milk (n = 13), and soy-based products (n = 4) purchased in Araçatuba (Brazil) had their F content measured using an ion-specific electrode, after hexamethyldisiloxane-facilitated diffusion. Powdered milk and infant formulae were reconstituted with deionized water, while ready-to-drink products were analyzed without any dilution. Using average infant body masses and suggested volumes of formula consumption for infants 1-12 months of age, possible F ingestion per body mass was estimated. Data were analyzed by descriptive analysis. Mean F content ranged from 0.02 to 2.52 mg/L in all samples. None of the cow's milk provided F intake higher than 0.07 mg/kg. However, two infant formulae, one powdered milk, and one soy-milk led to a daily F intake above the suggested threshold for fluorosis when reconstituted with deionized water. Assuming reconstitution of products with tap water at 0.7 ppm F, two infant formulae, five powdered milk, and four soymilks led to daily F intake ranging from 0.108 to 0.851 mg/kg. The results suggest that the consumption of some brands of infant formulae, powdered milk, and soy-based milk in the first year of age could increase the risk of dental fluorosis, reinforcing the need for periodic surveillance of the F content of foods and beverages typically consumed by young children.

Óleo funcional na dieta de vacas leiteiras

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo genômico da produção de leite e seus constituintes em bovinos da raça Guzerá

Pós-graduação em Genética e Melhoramento Animal - FCAV

Fontes proteicas para vacas leiteiras

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Intramammary coinfection by vaccinia virus and staphylococcus aureus in a bovine vaccinia outbreak

Introduction: Bovine vaccinia virus (VACV) is a well-known zoonotic agent related to exanthemous lesions in skin and mucous membranes of dairy cattle and humans, characterized by the formation of vesicles, pustules and ulcers. Mastitis is one of the most common infectious diseases of dairy herds. Bovine mammary infections are caused mainly by bacterial microorganisms, especially staphylococci. To the best of our knowledge, intramammary coinfection with VACV and Staphylococcus aureus in cows has not been reported previously. Case presentation: During an outbreak of exanthematic bovine VACV infection with animals showing vesicles, pustules and haemorrhagic ulcers on the teats, milk samples were collected for mastitis detection. Conclusion: The present report describes a case of intramammary coinfection by VACV and S. aureus in a bovine VACV outbreak.

Yield of different white button strains in sugar cane by product-based composts

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação in vitro da eficácia de extratos de plantas medicinais do Cerrado frente Staphylococcus aureos isolado de difetentes fontes de propriedades leiteiras

The objective of this study is to evaluate the potencial microbial activity in-vitro from the extract of some endemic plants from Cerrado such as Baccharis dracunculifolia, Cochlospermum regium, Croton antisyphiliticus, Eugenia dysenterica and Lippia sidoides, against the agent Staphylococcus aureus isolated from bovine mastitic milk, osteo from cow’s teat, milker equipament, nasal cavitites and milker’s gullet. The extracts were prepared from aerial parts as well as the reticular systems of plants using the solvents methanol, hexane and chloroform at a concentration of 10%. To evaluate the antimicrobial activity, the technique of microdilution in broth was used for determining the Minimal Inibitory Concentration (MIC) followed by the determination of Minimal Bactericidal Concentration (MBC). The extracts from Baccharis dracunculifolia and Croton antisyphiliticus, followed by extracts from Lippia sidoides, reported respectively, presented better inhibitory activity against the multiplication of the bacteria Staphylococcus aureus. Furthermore, the results demonstrate that the isolated strains from the milk and nasal cavities of the milker showed strong resistance against gentamicin, active agent commonly applied to combat mastitis bovine. However, there was sensitivity against extracts from the reported plants, reinforcing the importance of the medicinal plants as a therapeutic resource and its aplicability.

Análise multivariada de características reprodutivas e produtivas de vacas da raça Holandesa

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

The feeding activity of Colossoma macropomum larvae (tambaqui) in fishponds with water hyacinth (Eichhornia crassipes) fertilizer

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effects of hot and cold smoking processes on organoleptic properties, yield and composition of matrinxa fillet

Foi avaliado o efeito do processo de defumação a quente (45-90ºC/5 horas) e a frio (27-45ºC/10 horas) nas propriedades organolépticas, no rendimento e na composição dos filés de matrinxã (Brycon cephalus). Não houve diferença significativa no rendimento de filés defumados e não-defumados. As perdas no processo de defumação foram significativamente maiores para defumação a quente (19,37%) em comparação à defumação a frio (17,08%). O processo de defumação reduziu a umidade (in natura = 72,91%; defumado a quente = 58,51%; e defumado a frio = 59,68%) e aumentou os teores de proteína bruta, lipídios e cinzas. Houve diferença significativa somente nos teores de proteína no defumado a quente (28,07%) e defumado a frio (27,14%). O processo a frio resultou em melhor aparência e cor de filé, enquanto o processo a quente melhorou o sabor, o teor de sal e a aparência geral. O aroma e a textura não diferiram significativamente entre os processos. O processo de defumação a quente melhora as propriedades organolépticas e os níveis de proteína do filé de matrinxã.

Parâmetros Genéticos para a Produção de Leite, Gordura e Proteína em Bubalinos

The objective of this study was to estimate the genetic parameters affecting milk production (MP), fat (%F) and protein (%P) contents of buffalo milk. Restricted Maximum Likelihood (REML) using MTDFREML program under animal model analyzed a total of 1744 lactations records from 1268 cows. The means were: MP = 1259.47 +/- 523.09 kg, %F = 6.87 +/- 0.88% and %P = 3.91 +/- 0.61%. The estimates of repeatability and heritability coefficients were: MP = 0.38 and 0.24, %F = 0.28 and 0.21 and %P = 0.30 and 0.26, respectively. The estimated genetic and phenotypic correlations were MP x %F = -0.18 and -0.62, MP x %P = -0.23 and -0.59 and %F x %P = 0.50 and 0.77, respectively. According to these results it is possible to conclude that selection is a proper way to increase milk yield, fat and protein percentage. Although negative low values of genetic correlations among traits, it should be take into account that simultaneous selection based on these traits could not be so efficient.

Índices de seleção para um rebanho Caracu de duplo propósito

Neste trabalho, objetivou-se determinar índices de seleção para um rebanho da raça Caracu de duplo propósito, cujo objetivo de seleção (H) incluiu a venda de bezerros desmamados e a produção de leite. As características que compuseram H foram: produção total de leite, idade ao primeiro parto, período de serviço, peso à desmama e duração da vida produtiva. Foram propostos dois índices de seleção para H. Os critérios de seleção adotados no índice 1 foram: produção de leite na primeira lactação, primeiro período de serviço, peso à desmama (PD) e perímetro escrotal. No índice 2, foram consideradas as mesmas características, sendo, entretanto, o ganho médio diário do nascimento à desmama empregado como critério de seleção para PD. As análises estatísticas para a obtenção dos componentes de (co)variâncias e das estimativas dos parâmetros genéticos e fenotípicos foram realizadas pelo método da máxima verossimilhança restrita livre de derivada, por um modelo animal (uni e bi-característica). As informações zootécnicas e genealógicas, os preços e as quantidades dos insumos e dos produtos foram obtidos no escritório da empresa estudada. Os custos de produção e as receitas da atividade pecuária foram determinados para o período de 1994 a 2000. A equação de lucro foi tomada em base anual, usando-se valores médios para número de animais por categoria, características biológicas e preços..¹ O valor econômico para cada característica foi obtido pela derivada parcial da função de lucro em relação à característica em questão. Os dois índices econômicos de seleção trariam considerável resposta para o objetivo proposto. Entretanto, o índice 1, que incluiu PD, seria um pouco mais eficiente em termos de resposta à seleção total.

Genetic associations between accumulated productivity, and reproductive and growth traits in Nelore cattle

The total meat yield in a beef cattle production cycle is economically very important and depends on the number of calves born per year or birth season, being directly related to reproductive potential. Accumulated Productivity (ACP) is an index that expresses a cow's capacity to give birth regularly at a young age and to wean animals of greater body weight. Using data from cattle participating in the "Program for Genetic Improvement of the Nelore Breed" (PMGRN - Nelore Brasil), bi-trait analyses were performed using the Restricted Maximum Likelihood method based on an ACP animal model and the following traits: age at first calving (AFC), female body weight adjusted for 365 (BW365) and 450 (BW450) days of age, and male scrotal circumference adjusted for 365 (SC365), 450 (SC450), 550 (SC550) and 730 (SC730) days of age. Median estimated ACP heritability was 0.19 and the genetic correlations with AFC, BW365, BW450, SC365, SC450, SC550 and SC730 were 0.33, 0.70, 0.65, 0.08, 0.07, 0.12 and 0.16, respectively. ACP increased and AFC decreased over time, revealing that the selection criteria genetically improved these traits. Selection based on ACP appears to favor the heaviest females at 365 and 450 days of age who showed better reproductive performance as regards AFC. Scrotal circumference was not genetically associated with ACP. (C) 2007 Elsevier B.V. All rights reserved.