RESUMO: A mastite é considerada o maior problema dos animais destinados à produção de leite. Altera a sua composição e aumenta a contagem de células somáticas (CCS). Os micro-organismos envolvidos na doença podem ser origem infecciosa, como Staphylococcus aureus, ou ambiental, tal como Escherichia coli. A cultura bacteriana é uma ferramenta de diagnóstico e auxilia na detecção do patógeno causador da mastite. No entanto, fatores como fagocitose podem desencadear um resultado negativo. Quando estabelecido um programa de controle de mastite, o diagnóstico precoce e o início do tratamento adequado dos casos clínicos são fundamentais para se atingir os objetivos e seu sucesso, está relacionado com o patógeno envolvido. A indicação do tratamento de longa duração, ou terapia estendida, tem melhorado a resposta ao tratamento em casos de mastite por S. aureus, no entanto, com 30-50% de cura. Do ponto de vista do manejo dos animais, devido a alta contagiosidade deste patógeno, sua persistência no rebanho e custo em função ao tratamento, muitas vezes, o descarte do animal tem sido priorizado a fim de controlar os casos de mastite em propriedades. As medidas de controle são muito importantes para contribuir com a redução de casos de mastite por este patógeno. A indicação do tratamento intramamário associada com sistêmico tem poder efetivo em casos de mastite por E. coli, cujos casos agudos apresentam-se com sepse e toxemia. São abordados ainda aspectos de tratamentos alternativos das mastites, utilizados principalmente no processo orgânico de produção leiteira.

No abstract

The genus Mycoplasma includes more than 200 bacterial species that cause disease in animals. It is responsible for causing mastitis in bovines and may be related to other manifestations, such as arthritis and pneumonia in calves and heifers. The present study aimed to detect Mycoplasma bovis isolated from milk samples of bovine clinical mastitis, and to compare the isolation rates in two culture media: Hayflick and SP4. An initial screening was performed in order to detect the presence of the class Mollicutes in 1166 milk samples from clinical mastitis by the conventional Polymerase Chain Reaction (PCR) technique. According to the 1166 milk samples evaluated, 8.6% (100/1166) were positive to class Mollicutes. Regarding molecular analyses, 1.1% (13/1166) of conventional PCR for positive M. bovis was obtained and 0.9% (11/1166) in real-time PCR. The results of the microbiological culture of the 100 samples previously screened demonstrated that 6% (6/100) of colony growth have been developed when using the Hayflick medium, and 11% (11/100) when using the SP4 medium (including the positive on Hayflick medium). Concerning the 11 isolates obtained in the microbiological culture, conventional PCR confirmed M. bovis in nine of them, and two cultures were negative. In the phylogenetic analysis of the isolates, all of them were grouped in M. bovis and M. agalactiae clusters. The results confirmed the importance of the presence of M. bovis in the etiology of bovine clinical mastitis and reinforced the need for further studies to elucidate other Mycoplasma species that may be involved in bovine clinical mastitis in Brazil.

RESUMO.-Propriedades da agricultura familiar tem contribuído para aumentar a produção leiteira, e podem ser considerados importantes para cadeia produtiva do leite. A higiene no processo produtivo deve ser o foco principal para garantir maior produção e qualidade do leite. Monitorou-se a qualidade do leite de vacas, em propriedades da agricultura familiar, no município de Bofete/SP, antes e após a adoção de medidas de controle. Avaliaram-se 21 propriedades, selecionadas por conveniência. Após período inicial de 13 coletas para monitoramento de CCS e CBT, os proprietários dos dois grupos (G1 e G2) receberam orientações técnicas sobre mastite e qualidade do leite, em atividade de dia de campo. Os proprietários do G1 além dessas atividades receberam Family operated dairies have contributed to increase milk production and can be considered important in the milk production chain. Hygiene in the productive process must be the major focus to assure greater milk quality and production. The quality of milk from cows in family farms in the city of Bofete/SP was monitored before and after the establishment of control measures. Twenty-one dairy family farms, selected for convenience, were evaluated. After the initial period of 13 collections for SCC and TBC monitoring, farmers of the two groups (G1 and G2) received technical guidance about mastitis and milk quality during a day of field activity. G1 farmers, besides these activities, received intervention in the adopted management by means of technical visit and individual guidance as to adequate milking manner and hygienic milk production. Then, new fortnight collections (n=12) were performed, as previously, of a set of milk samples from each farm and both groups, as well as from the community tank. Climate variables were considered, such as rainfall, temperature and relative humidity. There was a variation in the results of each collection for both SCC/mL milk and TBC/mL milk in the two periods. As to SCC in G1, there was a statistically significant decrease (P < 0.02), while for TBC there was a slight increase, rather lower compared to the median value, which was 381x10 3 CFU/mL milk in G2. The median results of SCC/mL milk and TBC/mL milk from the community tank were greater in the two stages (periods), but much superior for TBC. Analysis of the climate variables evidenced an increase in the medians for all three evaluated parameters. The correlation between these variables and milk quality did not show differences for Log 10 of SCC and TBC. It can be concluded that the milking management hygiene was precarious.

Bovine mastitis has a negative impact on milk production and can pose risks to public health. The present study aimed to evaluate the quality of bovine milk from small farms in the Botucatu/SP region. Somatic cell counts (SCC), identification of pathogens involved in mastitis, and sensitivity antimicrobial profile of staphylococci isolated were performed. The presence of enterotoxin encoding genes in isolates of staphylococci obtained from milk was investigated. Milk samples from individual mammary quarters of cows were submitted to the California mastitis test (CMT) and SCC. Of the 239 dairy cows from 21 dairy herds evaluated (mean = 11.4 animals/property), two cows (0.8%) presented clinical mastitis and 86 (35.9%) subclinical mastitis. Bacterial culture was performed in 177 quarter milk samples. Staphylococci were identified in 55 (31.1%), corynebacteria in 45 (25.4%), streptococci in 25 (14.1%) and coliforms in four (2.3%) milk samples. Average SCC from culture-positive samples was 1598x103 cells/mL, in case of staphylococci was 1362x103 cells/ml, streptococci was 2857x103 cells/mL, corynebacteria was 976x103 cells/mL and in the cases of coliforms 1161x103 cells/mL were obtained. Staphylococci showed a high sensitivity (>95%) to cephalothin, cotrimoxazole, enrofloxacin, and gentamicin, with a 41.2% resistance to penicillin and 11.8% to oxacillin. Both coagulase positive (CPS) and negative staphylococci (CNS) carried genes encoding enterotoxins in 21.6% of the first group and 41.9% in the second. The sea gene was the most detected 45.8% (n=24) between them, followed by seb with 29.2% and sec with 25.0%. The sed gene was not identified. We highlight the potential risk to public health in the possibility of strains of Staphylococcus spp. enterotoxin-producing genes that can cause staphylococcal food poisoning.