Factors Affecting Levels of Airborne Bacteria in Dairy Farms: A Review

Abstract

This review attempts to reflect the importance of different factors that affect the environmental quality of dairy farms and must, therefore, be taken into account when considering the importance of environmental microbiology as a tool in the improvement of the quality of milk and dairy products. The effect of a factor such as temperature is vital for the dairy farm environment, especially when the temperatures are extreme, because a proper choice of temperature range improves the quality of the air and, thus, animal welfare. Similarly, the appropriate level of relative humidity in the environment should be taken into consideration to avoid the proliferation of microorganisms on the farm. Air quality, well-designed livestock housing, proper hygienic practices on the farm, stocking density, and the materials used in the livestock houses are all important factors in the concentration of microorganisms in the environment, promoting better welfare for the animals. In addition, a ventilation system is required to prevent the pollution of the farm environment. It is demonstrated that proper ventilation reduces the microbial load of the environment of dairy farms, enhancing the quality of the air and, therefore, the wellbeing of the animals. All this information is very useful to establish certain standards on dairy farms to improve the quality of the environment and, thereby, achieve better quality milk and dairy products.

MILK Symposium review: Microbiological quality and safety of milk from farm to milk collection centers in Rwanda

“…Our results are in the range of those reported in a study in Tanzania, where a prevalence of 10.1% was found in raw milk (Schoder et al, 2013). Farm environment is likely where reservoirs and vehicles for the Salmonella can be found (Quintana et al, 2020). It is possible that the Salmonella found in milk originated from milkers' hands, which may have touched reservoirs of Salmonella such as infected calves, shedding cows, or contaminated water (Marth, 1969).…”

A Combined Metabolomic and Metagenomic Approach to Discriminate Raw Milk for the Production of Hard Cheese

“…In particular, some specific dominant bacteria play an important role in udder homeostasis, which guarantees high milk quality [ 14 ]. Furthermore, the raw milk microbiota could be deeply influenced by specific aspects of the farm environment, including the teat surface, air, dust, barn conditions, and milking parlor environment, which are responsible for milk contamination [ 15 , 16 ]. Overall, it is fairly accepted that the microbial community in milk farm samples differs significantly from that of dairy plant samples; in this regard, according to the literature, psychrotolerant communities (mainly Pseudomonadales ) present in farm samples can proliferate during milk storage at refrigeration temperature [ 17 , 18 ].…”

Historical Evolution of Cattle Management and Herd Health of Dairy Farms in OECD Countries

“…Farms with a lower or appropriate stocking density have animals with normal behavior, which lie down for longer periods, and show greater ruminative comportment [ 114 , 115 ]. In addition, the concentration of disease-causing micro-organisms or particles in the environment is inversely proportional to the space available to animals [ 116 ]. The incidence of pathologies such as lameness, mastitis, and uterine disorders also increases with stocking density [ 96 ].…”