Milking procedure can affect anaerobic spore-forming bacteria in milk

during the ripening of hard cheeses. The relationship between ASFB content in dairy cows feed and milk is well documented, while there are only few evidences on the effects of different milking hygienic procedures on milk contamination. Three milking schemes were applied in an intensive dairy farm (70 lactating cows; 24.7 kg milk/d per cow on average) for three consecutive weeks during autumn over 2 years: forestripping (F), forestripping + postdipping (FP) or predipping + forestripping + postdipping (PFP). The pre and post dipping were carried out with commercial detergent solutions. Milk, feed and faeces samples and swabs of teat skin were collected in the last three days of each experimental week. The ASFB contents of hays and silages were not different between the years: maize silage had a slightly higher contamination compared to lucerne and Italian ryegrass hays (4.17±0.42 vs. 2.22±0.22 log10 MPN/g, average of the two hays), total mixed ration showed a different level of ASFB in the two years: 5.66 and 4.18 log10 MPN/g. The different milking procedure determined a decrease in the standard plate count and coliform count of milk: from 4.51 to 3.94 log10 CFU/mL and from 4.68 to 1.48 log10 CFU/mL respectively for F and PFP treatments. Milk ASFB was positively affected by the introduction of predipping: ASFB counts in milk were 2.48, 2.63 and 1.95 log10MPN/l in the first year and 2.45, 2.94 and 1.82 log10 MPN/l in the second year for treatment F, FP and PFP, respectively. The higher FP value suggests that the postdipping procedure does not have any effect on the reduction of ASFB contamination. Faeces showed a higher contamination of ASFB in comparison with milk: 3.52, 4.16 and 3.47 log10 MPN/g in the three treatments (average of the two years). The intensification of milking procedures had a positive effect also on the ASFB count of swabs applied on teat skin before clusters attachment: 2.18, 1.94 and 1.30 log10 MPN/swab for F, FP and PFP treatments, respectively, probably because the predipping reduced the faeces load on teat. The results obtained from this study underline the importance of the application of a proper milking procedure, in particular predipping, to reduce the ASFB contamination of milk.