Somaticell® as a screening method for somatic cell count from bovine milk

Os objetivos do presente estudo foram avaliar a correlação entre a contagem eletrônica de células somáticas (eCCS) com o Somaticell® sob diferentes níveis de contagem de células somáticas (CCS) do leite e patógenos causadores de mastites, além de calcular a sensibilidade, especificidade e valores preditivos do Somaticell® utilizando diferentes limites de CCS estabelecidos pelos diferentes países. Trezentos e quarenta amostras de leite foram coletadas assepticamente após realização do California Mastitis Test (CMT). O Somaticell® e a eCCS foram realizados em todas as amostras de leite. A correlação entre o Somaticell® e a contagem eletrônica foi determinada de acordo com o CMT, patógeno isolado e escore de eCCS. de acordo com os escores de CCS estabelecidos, 26,5% das amostras de leite apresentaram escore 1 (69-166 x10³células mL-1), 26,8% escore 2 (167-418x10³células mL-1), 27,4% escore 3 (419-760x10³células mL-1) e 19,4% escore 4 (761 to 1970x10³células mL-1). A eCCS e o Somaticell® apresentaram correlação positiva em quase todos os escores estudados (exceto escore 2 e 3). O valor de r obtido entre CCS e o Somaticell® foi de 0,32. Observou-se que, quando o limite de CCS estabelecido aumentou, a sensibilidade decresceu e os valores de especificidade aumentaram. Os valores preditivos apresentaram-se constantes em todos os limites. Quando o limite de CCS era baixo (<760,000 células mL-1), Somaticell® forneceu resultados consistentemente mais elevados que os valores de CCS. Já para amostras com CCS elevada, Somaticell® resultou em menores contagens que a eCCS. A correlação entre os dois métodos permaneceu relativamente constante em todas as condições e os valores de sensibilidade e especificidade do teste são altamente dependentes do limite estabelecido. Os resultados deste trabalho sugerem que o Somaticell® não é útil para avaliar a CCS do leite, pois seus resultados são significativamente diferentes da eCCS, no entanto, pode ser utilizado como método de triagem, tal como o CMT, para a detecção do aumento da CCS do leite.

Peracute bovine mastitis caused by Klebsiella pneumoniae

Relata-se a ocorrência de graves sintomas de mastite hiperaguda em vaca, causada por Klebsiella pneumoniae, na terceira semana de lactação. Descrevem-se aspectos epidemiológicos, sintomas clínicos, procedimentos de diagnóstico microbiológico, conduta terapêutica e medidas de controle.

Molecular identification and thermoresistance to boiling of Nocardia farcinica and Nocardia cyriacigeorgica from bovine bulk tank milk

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

Relationship between teat-end condition, udder cleanliness and bovine subclinical mastitis

The aims of the present study were to relate intramammary infection (IMI) occurrence and somatic cell count (SCC) with teat-end condition (TEC) and udder cleanliness (UC). Milk samples from 1931 teats were evaluated according to the presence of IMI and SCC. Scores were applied to teats according to the TEC and to UC. Teats ends with a very rough ring had the largest number of IMI when compared to the other three categories, as well as animals with dirtier udders. The change in a TEC score increased by around 30% the chance of IMI. Also, the chance of the animal developing IMI increased by approximately 47% when the UC score increased. No significant association between both scores and quarter SCC was found. It can be concluded that animals with very rough teat end rings and very dirty udders have a greater predisposition to IMI. (C) 2011 Elsevier Ltd. All rights reserved.

Molecular detection of Streptococcus agalactiae in bovine raw milk samples obtained directly from bulk tanks

Mastitis is the most common infectious disease affecting dairy cattle; in addition, it remains the most economically important disease of dairy industries around the world. Streptococcus agalactiae, a contagious pathogen associated with subclinical mastitis, is highly infectious. This bacterium can cause an increase in bulk tank bacterial counts (BTBC) and bulk tank somatic cell counts (BTSCC). The microbiological identification of S. agalactiae in samples from bulk tanks is an auxiliary method to control contagious mastitis. Thus, there are some limitations for time-consuming cultures or identification methods and additional concerns about the conservation and transport of samples. Bulk tank samples from 247 dairy farms were cultured and compared through polymerase chain reaction (PCR), directed to 16S rRNA genes of S. agalactiae, followed by BTBC and S. agalactiae isolation. The mean value of BTBC was 1.08 x 10(6) CFU mL(-1) and the bacterium was identified through the microbiological method in 98 (39.7%; CI95% = 33.8-45.9%) and through PCR in 110 (44.5%; CI95% = 38.5-50.8%) samples. Results indicated sensitivity of 0.8571 +/- 0.0353 (CI95% = 0.7719-0.9196) and specificity of 0.8255 +/- 0.0311 (CI95% = 0.7549-0.8827). The lack of significant difference between microbiological and molecular results (kappa = 0.6686 +/- 0.0477 and CI95% = 0.5752-0.7620) indicated substantial agreement between the methods. This suggests that PCR can be used for bulk tank samples to detect contagious mastitis caused by S. agalactiae. (C) 2011 Elsevier Ltd. All rights reserved.

In vitro algaecide effect of sodium hypochlorite and iodine based antiseptics on Prototheca zopfii strains isolated from bovine milk

Prototheca zopfii has been considered one of the most important causes of environmental mastitis in Brazil. These algae are refractory to conventional therapy and cause great damage to the mammary gland. The present study evaluated the in vitro algaecide effect of sodium hypochlorite and iodine based antiseptics on 27 P. zopfii strains isolated from the milk of cattle. Low concentrations of sodium hypochlorite (0.0390625-0.15625%) and iodine (0.15625-0.625%) were effective against the isolates. These antiseptics may be recommended for hygiene routines, pre and postdipping and cauterization of bovine mammary glands infected by P. zopfii. (C) 2009 Elsevier Ltd. All rights reserved.

Importance of Antirabies Revaccination for an Adequate Antirabies Protection in Bovine Newborns

The transfer of antirabies immunoglobulins in cows that were prime vaccinated and cows that were revaccinated against rabies correlated to the serum titers in their offspring was evaluated. The results demonstrated that revaccination against rabies during pregnancy induces neutralizing antibody titers at a protective level that are transferred directly to calves through colostrum and reinforce the importance of revaccination for improved colostral antibody transfer and offspring protection against rabies.

Identification and characterization of polymorphisms within the 5' flanking region, first exon and part of first intron of bovine GH gene

The aim of the present study was to identify and characterize polymorphisms within the 5' flanking region, first exon and part of first intron of the bovine growth hormone gene among different beef cattle breeds: Nelore (n = 25), Simmental (n = 39), Simbrasil (n = 24), Simmental x Nelore (n = 30), Canchim x Nelore (n = 30) and Angus x Nelore (n = 30). Two DNA fragments (GH1, 464 bp and GH2, 453 bp) were amplified by polymerase chain reaction and then used for polymorphism identification by SSCP. Within the GH1 fragment, five polymorphisms were identified, corresponding to three different alleles: GH1.1, GH1.2 and GH1.3 (GenBank: AY662648, AY662649 and AY662650, respectively). These allele sequences were aligned and compared with bovine GH gene nucleotide sequence (GenBank: M57764 and AF118837), resulting in the identification of five insertion/deletions (INDELs) and five single nucleotide polymorphisms (SNPs). In the GH2 fragment two alleles were identified, GH2.1 and GH2.2 (GenBank: AY662651 and AY662652, respectively). The allele sequences were compared with GenBank sequences (M57764, AF007750 and AH009106) and three INDELs and four SNPs were identified. In conclusion, we were able to identify six new polymorphisms of the bovine GH gene (one INDEL and five SNPs), which can be used as molecular markers in genetic studies.

Traceability of bovine meat and bone meal in poultry by stable isotope analysis

Bovine meat and bone meal (MBM) was widely used in animal diets until outbreaks of Bovine Spongiform Encefalopathy (BSE) occurred in some countries. It has not been confirmed yet whether or not BSE may be transmitted to man through chicken meat originated from poultry that had been fed diets containing MBM. Therefore, consumers nowadays express preference for meat originated from birds fed exclusively vegetable diets. This study analyzed samples of major breast muscle (Pectoralis major) using mass spectrometry of stable isotopes (carbon and nitrogen) as a means to assess the presence of MBM in broiler diets, a technique that might be used in the certification of poultry quality. A total of 150 day-old chicks were reared in five randomized treatments with increasing MBM dietary inclusion levels (0, 1, 2, 4 and 8%). on day 42, breast muscle samples were collected from three birds per treatment and used in the determination of 13C/12C and 15N/14N isotope ratios. The breast muscle isotope values were expressed as delta in parts per thousand (delta ). The following carbon isotope values (13C) were found: 18.74 ±0.11, 18.51 ±0.19, 18.24 ±0.10, -17.79 ±0.12, and -17.15 ±0.15 for 0, 1, 2, 4 and 8% MBM dietary levels, respectively. Nitrogen isotope values (15N) were 1.65 ±0.14, 1.65 ±0.28, 1.72 ±0.08, 1.95 ±0.16, and 2.52 ± 0.09 for 0, 1, 2, 4 and 8% MBM dietary levels, respectively. This study showed important differences in delta13C and delta15N values in breast meat, evidencing a simultaneous enrichment of this isotopic pair, which allowed tracing MBM in bird diets. Analysis of carbon and nitrogen stable isotopes may be used to ensure feeding with exclusively vegetable diets, and might also be used as a reliable evaluation tool in broiler meat certification. The diet with 1% inclusion level of MBM and the exclusively vegetable diet showed similar results.

Alternative genotyping method for the single nucleotide polymorphism A2959G (AF159246) of the bovine CAST gene

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

Detection and quantification of Duffy antigen on bovine red blood cell membranes using a polyclonal antibody

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Bovine gene polymorphisms related to fat deposition and meat tenderness

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

Plasma progesterone concentration in beef heifers receiving exogenous glucose, insulin, or bovine somatotropin

Three experiments were conducted to evaluate plasma concentrations of glucose, insulin, IGF-I, and progesterone (P4) in pubertal beef heifers receiving exogenous glucose, insulin, or sometribove zinc. All heifers used had no luteal P4 synthesis but received a controlled internal drug-releasing device containing 1.38 g of P4 to estimate treatment effects on hepatic P4 degradation. In Exp. 1, 8 pubertal, nulliparous Angus x Hereford heifers (initial BW = 442 +/- 14 kg; initial age = 656 +/- 7 d) were randomly assigned to receive, in a crossover design containing 2 periods of 10 h, intravenous (i.v.) infusions (10 mL) of insulin (1 mu g/kg of BW; INS) or saline (0.9%; SAL). Treatments were administered via jugular venipuncture in 7 applications (0.15 mu g insulin/kg BW per application) 45 min apart (from 0 to 270 min). Blood samples were collected immediately before each infusion as well as at -120, -60, 330, 390, and 450 min relative to the first infusion. Heifers receiving INS had greater (P < 0.01) plasma insulin, reduced (P <= 0.04) plasma glucose and IGF-I, and similar (P = 0.62) plasma P4 concentrations compared with SAL heifers. In Exp. 2, the same heifers were assigned to receive, in a similar experimental design as Exp. 1, i.v. infusions (10 mL) of 1) insulin (1 mu g/kg BW) and glucose (0.5 g/kg BW; INS+G) or 2) SAL. Heifers receiving INS+G had greater (P <= 0.02) plasma insulin, glucose, and P4 but reduced (P = 0.01) plasma IGF-I concentrations compared with SAL heifers. In Exp. 3, the same heifers were assigned to receive, in a crossover design containing 2 periods of 14 d, subcutaneous (s.c.) injections of 1) 250 mg of sometribove zinc (BST) or 2) SAL. Blood samples were collected 3 h apart (0900, 1200, 1500, and 1800 h) from heifers on d 6, 8, and 10 relative to treatment administration (d 1). Heifers receiving BST had greater (P < 0.01) plasma glucose and IGF-I and similar (P >= 0.67) plasma insulin and P4 concentrations compared with SAL heifers. Results from this series of experiments suggested that concurrent increases in glucose and insulin are required to reduce hepatic catabolism and increase plasma concentrations of P4 in bovine females.