Influence of educational level of dairy farmers, suitability of facilities, and milk production profile on bacterial contamination of milk and milking environment

The objective of this study was to verify whether there is an association between bacterial contamination of milk with their milking practices and the socioeconomic profile of milkers. Fourteen farms were studied, which were characterized in terms of workers' socioeconomic backgrounds and microbiological profiles of the main contamination sites during the milking. Results were compared statistically. Aerobic mesophiles (AM), total coliforms (TC), and coagulase positive staphylococci (CPS) were enumerated, and Salmonella spp. was surveyed in water, hands, teats, equipment, utensils, and milk (from the cooling tank). The average age of farmers was 47 years old, 24 of which were dedicated to dairy farming. Only one farm had an outsourced workforce. Of all farmers, 93% performed two milkings a day through a mechanical bucket milking system, using piped well-water. In the milking parlors, there were sinks and/or faucets, floor, ceiling, and electric lighting. Before milking, milkers had their hands washed, discarded the first three milk jets, washed the cows' udders, and dried them with disposable tissue paper, but did not perform pre- and/or post-dipping. Raw milk was refrigerated in all evaluated farms immediately after milking, mostly in an expansion tank. Average contamination by AM was 3.19 log CFU/cm² or mL and by TC of 0.77 log CFU/cm² or mL. CPS was not detected in water, but in the other samples, the average count was 0.75 log CFU/cm² or mL. Salmonella spp. was not detected in the samples obtained in the evaluated farms. There were significant differences among farms, and raw milk contamination was influenced by farmers' schooling level, performance or not of good practices, conditions of the facilities, and production volume

Relationship between milking time, feeding behavior and performance of dairy cows

Os sistemas de criação de vacas leiteira a pasto possuem muitos benefícios, incluindo econômicos, ambientais e bem-estar animal e social. Porém variações na estrutura das pastagens, nas condições climáticas, estado fisiológico e sanitário do animal podem provocar oscilações na produção e composição do leite, afetando o retorno econômico da produção. Os bovinos seguem um ciclo circadiano, intensificando o pastejo ao amanhecer e entardecer. Neste sistema, as vacas não ficam o tempo todo na pastagem. Geralmente são retiradas do piquete para serem manejadas, principalmente para a ordenha e suplementação. Os horários de ordenha compreendidos entre 5h30 e 7h e 17h e 18h30 se sobrepõem aos momentos de maior pastejo. Pouco se tem descrito na literatura sobre este assunto, sendo os horários de ordenha determinados em função da disponibilidade de mão-de obra, intervalo entre ordenhas e recolhimento do leite. O objetivo deste estudo foi avaliar o efeito de alterar o horário das ordenhas do habitualmente realizado pelas propriedades leiteiras para às 8h e às 16h sobre o comportamento ingestivo e desempenho produtivo de vacas leiteiras mantidas em sistema pastoril. Trinta e seis vacas, de duas fazendas (A e B) foram avaliadas durante o manejo convencionalmente feito na propriedade e após a troca do horário de ordenha. Coletaram-se parâmetros referentes a produção e composição do leite, bem como os tempos em atividades do repertório alimentar. A produção de leite manteve-se inalterada em ambas as propriedades, porém o teor de gordura, sólidos totais e nitrogênio ureico do leite apresentou diferença entre os tratamentos na fazenda B. O tempo de pastejo total e vespertino na fazenda B aumentou após a troca. A mudança no horário de ordenha, sobretudo da tarde, pode beneficiar a atividade de pastejo nos momentos de maior motivação do animal em colher o alimento, mostrando-se uma alternativa de manejo em sistemas pastoris.Grazing systems for dairy cows have many benefits, including economic, environmental, social animal and welfare benefits. However, variations in pasture structure, weather conditions, physiological and health status of the animal can cause fluctuations in milk yield and composition that may affect the economic return. Cattle’s activities follow a circadian cycle, with two intense grazing bouts at dawn and dusk. Generally, cows do not stay in the pasture all the time. They are usually taken out from the pasture to be managed, mainly for milking and supplementation few times a day. The conventional milking times overlap with the main grazing periods. Little has been described in the literature about this subject, and milking times are determined according to the availability of labor, milk collection and transport schedules and milking intervals. The aim of this study was to evaluate the effects of milking at 8:00 a.m. and 4:00 p.m. in contrast to the milking times usually used in dairy farms, on the ingestive behavior, productive performance and feed intake of grazing dairy cows. Thirty-six cows from two farms were evaluated in the conventional management and after changing milking times to 8 am and 4 pm. Milk yield and milk composition parameters were collected, as well as the time spent on feeding repertoire activities. Milk production remained unchanged on both farms, but the fat content, total solids, and urea nitrogen content of the milk increased between treatments on farm B. Total and afternoon grazing time on farm B increased after the change. Change in milking schedule especially anticipating milking at the afternoon can favor grazing activity at times of greater motivation of the animal to collect food, proving to be a management alternative to dairy farms in pasture systems