Incidence of milk leakage after dry-off in European dairy herds, related risk factors, and its role in new intramammary infections

Abstract

DO, where the herd incidence varied between 0.0 and 77.8%. The reduction in number of milkings in the weeks before DO had statistically significant effect on the ML incidence. When the milking frequency was reduced from 3 times/d to 2 or maintained at twice a day, cows had 11 (95% CI = 3.43-35.46) or 9 (95% CI = 1.85-48.22) times higher odds of leaking milk, respectively, compared with cows where the milking frequency was reduced from twice to once a day. Also, the milk production 24 h before DO was associated with ML incidence. Hence, cows with a milk production between 13 and 21 L or above 21 L had 2.3 (95% CI = 1.48-3.53) and 3.1 (95% CI = 1.79-5.3) times higher odds of leaking milk, respectively, compared with cows with a milk production below 13 L. A higher ML incidence was present in the group of cows with an average ISCC in the last 3 mo before DO ≥200,000 cells/mL (odds ratio = 1.7; 95% CI = 1.13-2.41) compared with cows with an average ISCC <100,000 cells/mL. Quarters with ML tended to have 2.0 times higher odds of developing clinical mastitis compared with quarters not leaking milk. Cows with ML tended to have 1.5 times higher odds of intramammary infections (i.e., an increase of ISCC or clinical mastitis) compared with cows without ML.

Drying-off practices on Swiss dairy farms: Status quo and adoption potential of integrating incomplete milking

“…Our results offer the opportunity to discuss observations of milk leakage, increased vocalizations, and decreased lying time associated with dry-off in more detail. First, milk leakage poses a risk to udder health because the likelihood of developing new IMI is higher for cows with milk leakage than for cows without milk leakage (De Prado-Taranilla et al, 2020). The risk of developing milk leakage after dry-off increases with higher milk yield at dry-off (Bertulat et al, 2013;Gott et al, 2016;De Prado-Taranilla et al, 2020).…”

“…First, milk leakage poses a risk to udder health because the likelihood of developing new IMI is higher for cows with milk leakage than for cows without milk leakage (De Prado-Taranilla et al, 2020). The risk of developing milk leakage after dry-off increases with higher milk yield at dry-off (Bertulat et al, 2013;Gott et al, 2016;De Prado-Taranilla et al, 2020). About one quarter of our participants reported observing milk leakage associated with dry-off rather often to always, but increased annual milk yields were not significantly associated with the frequency of observed milk leakage.…”

“…Consistent with our findings, De Prado-Taranilla et al (2020) also did not observe a significant association between 305-d milk production and milk leakage, although milk production before dry-off was associated with milk leakage. Therefore, the authors suggested that most milk leakage after dry-off may be prevented if milk production in high-yielding cows is reduced before dry-off (De Prado-Taranilla et al, 2020). Second, increased vocalizations were observed when cows were fed a nutrient-restricted diet before dry-off, likely due to hunger (Valizaheh et al, 2008;Tucker et al, 2009;Franchi et al, 2021).…”

“…With the increased milk production potential of the modern dairy cow (Barkema et al, 2015), drying-off has become more challenging. High milk yield at dry-off was found to increase the risk for developing milk leakage (Bertulat et al, 2013;Gott et al, 2016;De Prado-Taranilla et al, 2020) and IMI during the dry period (Rajala-Schultz et al, 2005;Newman et al, 2010) because the keratin plug formation in the teat canal was impaired (Dingwell et al, 2004). In addition, high milk yield at dry-off was associated with increased udder pressure and stress levels after dry-off, and abrupt cessation of milking may cause discomfort and pain (Bertulat et al, 2013;Silanikove et al, 2013;Zobel et al, 2015).…”

Cows enrolled in a pilot randomized clinical trial evaluating pegbovigrastim administered to dairy cows at dry-off had reduced incidence of intramammary infection

“…It is well established that cows are most susceptible to new IMI during early dry and peripartum periods, 2 due to increased risk of milk leakage, impairment of neutrophils, 1 and persistence of IMI acquired during the previous lactation. 2,6,28 Cows are more resistant to new IMI when the mammary gland reaches a steady involution phase. 2 Thus, acceleration of mammary gland involution could help reduce risks of IMI during the dry and subsequent peripartum periods.…”