Lívia Castelani | Universidade de São Paulo (original) (raw)

Uploads

Papers by Lívia Castelani

2010 Pittsburgh, Pennsylvania, June 20 - June 23, 2010, 2010

... SA de A. Fernandes, PhD, Animal Scientist ... 37p. (Documento 34). FAÇANHA, DAE et al. Compor... more ... SA de A. Fernandes, PhD, Animal Scientist ... 37p. (Documento 34). FAÇANHA, DAE et al. Comportamento fisiológico de bezerros da raça holandesa, submetidos a diferentes instalações e dietas líquidas, durante o período hibernal, em Santa Maria, RS. ...

Animal Science Journal, 2014

Biofilm formation and antimicrobial resistance of Staphylococcus aureus are important virulence f... more Biofilm formation and antimicrobial resistance of Staphylococcus aureus are important virulence factors in cases of mastitis in dairy cows. However, few studies have investigated mastitis strains isolated from heifers. Within this context, the objective of the present study was to investigate biofilm formation on Congo red agar, the presence of the icaA and icaD genes by polymerase chain reaction (PCR), and the percentage of in vitro antimicrobial resistance of 110 S. aureus isolates from mammary gland secretions of heifers and cows with mastitis. PCR detected the icaA and icaD genes in 98% and 100% of isolates, respectively. However, only 55.5% of all isolates produced a biofilm on Congo red agar. Antimicrobial susceptibility testing revealed that 47.0% of isolates from heifers and 70.4% of isolates from cows were resistant to at least one of the antimicrobial agents tested. Resistance to penicillin and/or ampicillin was the most frequent (44.5%). These results indicate the need to implement prophylactic and control measures of mastitis for heifers. Heifers and cows can carry resistant strains with the capacity of biofilm production, a fact representing a threat to public health and animal well-being and generating losses to dairy farmers.

International Journal of Molecular Sciences, 2013

Staphylococcus aureus is among the main etiologic agents of bovine mastitis. A total of 83 isolat... more Staphylococcus aureus is among the main etiologic agents of bovine mastitis. A total of 83 isolates of S. aureus from mammary glands of primiparous heifers were collected in the prepartum, calving and during lactation. For lactating cows, a total of 27 isolates of S. aureus from mammary glands were collected during lactation. The samples were taken in two dairy farms located in Sao Paulo State, Brazil. The highest frequency of S. aureus isolation in heifers was at the end of lactation. Strains were typified through Pulsed-field gel electrophoresis (PFGE) and grouped according to patterns of restriction enzyme SmaI. PFGE generated seven clonal profiles that were grouped into three different lineages, with the LA lineage being predominant and identified in heifers, as well as in the cows from the two regions studied. It was concluded that the cows showed a significant source of dispersion of S. aureus. At the first lactation the heifers were infected by the same clonal profiles of S. aureus which were isolated from multiparous lactating cows. The heifers were infected during milking over the months of lactation.

Italian Journal of Animal Science, 2014

Twenty-four dairy cows, with daily average milk production of 18.1 kg, were fed diets containing ... more Twenty-four dairy cows, with daily average milk production of 18.1 kg, were fed diets containing different selenium (Se) sources. The purpose of this paper is to evaluate the effects of such diets on milk production and quality, on the occurrence of mastitis, and on physiological variables. During the experimental period (124 days), all the cows received the same diet: a total mixed feed with 0.278 mg.kg -1 DM of selenium. In the inorganic Se treatment, the selenium source was sodium selenite and in the organic Se treatment the source was selenium yeast (Saccharomyces cerevisiae CNCM I-3060). There were no significant differences in milk yield or in Se concentration in the milk. No significant differences between the treatments were observed in protein, lactose, solids-not-fat andpercentage of total solids. The animals subjected to the organic Se treatment presented higher (P=0.013) percentage of milk fat and lower (P=0.014) somatic cell count (SCC) than those subjected to the inorganic Se treatment. There was no significant difference in subclinical mastitisas determined by the California Mastitis Test (CMT) between the treatments. However, both Se sources reduced the incidence of mastitis (subclinical positive mastitis and strongly positive mastitis) between the pre-experimental and experimental phases. There was no significant difference in rectal temperature (RT) between the treatments. Respiratory frequency (RF) was lower (P=0.027) in the inorganic treatment than in the organic one, whereas haircoat temperature (HT) was lower (P=0.007) in the organic treatment than in the inorganic one.

... Luiz Francisco Zafalon1 *, Juliana Rodrigues Pozzi Arcaro2, Antônio Nader Filho3, Luciano Men... more ... Luiz Francisco Zafalon1 *, Juliana Rodrigues Pozzi Arcaro2, Antônio Nader Filho3, Luciano Menezes Ferreira4, Lívia Castelani5, Fabiane Benvenutto5 ... coagulase lenta com plasma de coelho, seguidas pela verificação da produção de acetoína (HOLMBERG, 1973; HOLT et al ...

... Luiz Francisco Zafalon1 *, Juliana Rodrigues Pozzi Arcaro2, Antônio Nader Filho3, Luciano Men... more ... Luiz Francisco Zafalon1 *, Juliana Rodrigues Pozzi Arcaro2, Antônio Nader Filho3, Luciano Menezes Ferreira4, Lívia Castelani5, Fabiane Benvenutto5 ... foram submetidas aos testes diagnósticos, de acordo com procedimentos preconizados por Holmberg (1973) e Holt et al. ...

... Fundap Instituto de Zootecnia Centro de Bovinos de Leite, Nova Odessa-SP 4 Bolsista Tre... more ... Fundap Instituto de Zootecnia Centro de Bovinos de Leite, Nova Odessa-SP 4 Bolsista Treinamento técnico Fapesp / Processo no 06/50206-056 Endereço e autor para correspondência: Luiz Francisco Zafalon Embrapa ... CUNHA NETO, A.; SILVA, CGM; STAMFORD ...