Management practices and forage quality affecting the contamination of milk with anaerobic spore-forming bacteria

Abstract

BACKGROUND Anaerobic spore‐forming bacteria (ASFB) in milk derive from the farm environment, and the use of silages and management practices are the main responsible of milk ASFB contamination. The aim of this study was to evaluate the relationships between feeding, milking routine and cow hygiene and milk and Grana Padano cheese (produced with and without lysozyme) ASFB contamination. RESULTS The study involved 23 dairy farms. ASFB in corn silage were on average 2.34 ± 0.87 log10 MPN g−1. For grass, Italian ryegrass and alfalfa, ASFB (log10 MPN g−1) were numerically higher for silages (3.22) than hays (2.85). The use of corn silages of high quality (high lactic and acetic acids concentrations) decreased the milk ASFB contamination, whilst the use of herbage silages did not affect it. The presence (>40%) of cows with dirty udders increased the ASFB contamination of milk, while forestripping had a positive effect (−9% ASFB). Ripened Grana Padano had an ASFB count below the analytical limit; Clostridium tyrobutyricum DNA was found only in wheels produced without lysozyme, which also showed late blowing. CONCLUSION The factors increasing milk spore contamination were corn silage quality, cow udder hygiene and inadequate milking routine. Late blowing was present only in cheeses without lysozyme. © 2014 Society of Chemical Industry

New assessment based on the use of principal factor analysis to investigate corn silage quality from nutritional traits, fermentation end products and mycotoxins

“…Borreani and Tabacco and Vissers et al . reported a higher number of clostridia spores in peripheral than core corn silage samples, confirming that aerobic deterioration could raise concentrations of clostridia spores in silages, thus increasing the possible risk of milk contamination . In accordance with this, a higher concentration of fermentation end‐products ascribable to clostridia activity was observed in peripheral than core samples, particularly in samples collected from lateral parts of the working face.…”

“…However, data variability associated with PC2 subject‐based scores (standard deviations of 0.43, 0.93 and 1.44 for core, lateral and apical samples, respectively) suggested that fermentation end‐products associated with clostridia strains occurred at high concentrations also in core and apical samples. A possible transfer of clostridia spores could occur from silage to milk via faecal contamination of the teats, with negative impact on cheese quality …”

Occurrence of Clostridium spp. in ewe’s milk: enumeration and identification of isolates

“…Indeed, while for cow's milk, high clostridial spore counts are mainly recorded in winter, due to silage feeding (Driehuis 2013;Zucali et al 2015), for ewe's milk, high MPN counts have also been observed in summer. This could be due to environmental factors, husbandry and feeding practices other than silage feeding, such as wool spore contamination, milking hygiene, and an incorrect management of the bedding, especially during anomalous summer seasons (i.e., particularly rainy or dry).…”

Multi-dimensional assessment and scoring system for dairy farms

“…In order to create an easy-to-use tool for multiple quality aspects (animal welfare, environmental and economic sustainability of dairy farms, microbiological, nutritional and nutraceutical quality of milk), 19 variables were selected according to their informative characteristics and importance, resulted from previous studies Zucali et al 2014), and to their prevalence and variability in the sample (Figure 1).…”