Sudden dry-off is an established management practice in the dairy industry. But milk yield has been increasing continuously during the last decades. There is no information whether the dry-off procedure, which often results in swollen and firm udders, causes stress, particularly in high-producing dairy cows. Therefore, we evaluated the effect of a sudden dry-off on extramammary udder pressure and the concentration of fecal glucocorticoid metabolites (i.e., 11,17-dioxoandrostane, 11,17-DOA) as an indirect stress parameter. Measurements were carried out within the last week before dry-off and until 9d after dry-off considering 3 groups of milk yield (i.e., low: <15 kg/d, medium: 15-20 kg/d, and high: >20 kg/d). Udder pressure increased in all yield groups after dry-off, peaked at d 2 after dry-off and decreased afterwards. Pressures were highest in high-yielding cows and lowest in low-yielding cows. But only in high-yielding cows was udder pressure after dry-off higher than before dry-off. Baseline 11,17-DOA concentrations depended on milk yield. They were highest in low-yielding (121.7 ± 33.3 ng/g) and lowest in high-yielding cows (71.1 ± 30.0 ng/g). After dry-off, 11,17-DOA increased in all yield groups and peaked at d 3. Whereas in medium- and high-yielding cows 11,17-DOA levels differed significantly from their respective baseline during the whole 9-d measuring period, low-yielding cows showed elevated 11,17-DOA levels only on d 3 after dry-off. However, especially the increase in 11,17-DOA after dry-off between the 3 yield groups was considerably different. Mean 11,17-DOA increase from baseline to d 3 was highest in high-yielding cows (129.1%) and considerably lower in low-yielding cows (40.1%). The highest fecal 11,17-DOA concentrations were measured on d 3 after dry-off, indicating that the stress was most intense on d 2, which is due to an 18-h time lag; at about the same time, udder pressure peaked. Our results showed a negligible effect of a sudden dry-off on low-yielding cows. High-yielding cows, however, faced high extramammary pressures and increased glucocorticoid production. Considering animal welfare aspects, a review of the current dry-off strategies might be warranted.

While dry cow management is important for health, milk production and fertility information on drying-off procedures implemented on commercial dairy farms is lacking. Current drying-off management procedures on commercial dairy farms were evaluated using a questionnaire and results compared with recommendations given in the current literature. Ninety-one participants from a farmer education event completed the survey. On average, cows were dried off seven weeks before calving. Only 9.9 per cent of the farms had a dry period length of five weeks or less. A continuous milking regime without dry period was not established on any farm participating in the survey. Most farmers performed an abrupt drying-off (73.0 per cent). Only 11.8 and 15.0 per cent attempted to lower milk yield prior to drying-off by reducing milking frequencies and adjusting feed rations, respectively. While a blanket antibiotic dry cow treatment was carried out on 79.6 per cent of the farms, selective dry cow treatment was not mentioned by any farmer. Although 77.4 per cent preponed the drying-off date in low-yielding cows, an altered drying-off procedure in high-yielding dairy cows was rare (9.7 per cent). This survey provides an insight into drying-off procedures currently applied on commercial dairy farms in northern Germany.

Most measurements of udder pressure are based on devices connected to the gland cistern via cannulas. These devices are either inserted in the teat canal or surgically implanted into the udder tissue. In this study, instead of invasively measuring intramammary udder pressure, we measured the udder firmness noninvasively on the udder surface via a dynamometer. These are commonly used in food research to determine crispiness and firmness of fruits. The objective of this study was to validate a hand-held dynamometer for measuring udder firmness in dairy cows. Specifically we set out to determine inter-investigator repeatability considering potential confounders such as investigator, location, and cow. Through modifications in the standard operating procedure for the measurements, inter-investigator repeatability increased from correlation coefficient=0.80 (n=275) to correlation coefficient=0.94 (n=634). Measurements in different locations within the left hind quarter revealed a firmness gradient from the upper to the lower measuring point. Measurements between the 4 quarters within a cow displayed differences, except between both hind quarters. In 94.8% of the udders, firmness decreased due to milking. The correlation coefficient, however, between firmness changes and milk yield was low (r=0.42, n=153). Our data provide evidence that the dynamometer, although imperfect, does provide a reasonable measure of udder firmness and can be a useful tool in research related to animal health and welfare. However, a standardized operating protocol should be followed to minimize confounding by investigator, location, and quarter.

In recent years, relationships between high milk yield at dry off, higher prevalence for new intramammary infections, and stress were evaluated. Considering increasing milk yield, dry off methods need to be refined to ensure udder health and animal welfare, especially in high-yielding dairy cows. The present work evaluated the effect of a single cabergoline injection (Velactis, Ceva Santé Animale, Libourne, France) at dry off on udder pressure, milk leakage, and signs of udder pain after dry off. A total of 234 high-yielding (≥16 kg of milk/d) dairy cows was enrolled 7 d before and followed up until 14 d after dry off. Cows were dried off without preparation (i.e., no feed change or intermittent milking before dry off) and treated with a single i.m. injection of 5.6 mg of cabergoline (n = 115) or placebo (n = 119) after last milking. Udder characteristics were measured 4 d before (i.e., before and after milking) and 1, 2, 3, 7, 10, and 14 d after dry off. Udder pressure was evaluated utilizing a hand-held dynamometer. Milk leakage and signs of udder pain were noted as binary variables. Whereas udder pressure baseline values after last milking did not differ between treatment groups (0.541 ± 0.15 kg), cabergoline significantly reduced udder pressure in primiparous but not in multiparous cows after dry off. Differences between cabergoline- and placebo-treated primiparous cows could be evaluated until 3 d after dry off. The first day after dry off, udder pressure in placebo- and cabergoline-treated cows increased by 115% and 42.3%, respectively. Whereas pressure values in placebo cows were highest on the first day after dry off (1.16 ± 0.61 kg) and slowly decreased afterward, udder pressure in cows treated with cabergoline had a slower increase and peak only 2 d after dry off (0.94 ± 0.44 kg). Furthermore, cabergoline caused a reduction of milk leakage, a known factor for new intramammary infections. Only 11.3% of cows treated with cabergoline showed milk leakage compared with 21.0% placebo-treated cows. Additionally, cows with placebo treatment were 2.8 times as likely to show signs of udder pain compared with cows treated with cabergoline. An effect of cabergoline on udder pressure, milk leakage, and udder pain was limited to the first week after dry off. Our data provide evidence that a single injection of cabergoline reduces risk factors for udder health and animal welfare problems around dry off in high-yielding dairy cows with more than 16 kg of milk/d. Further research is warranted, however, to investigate if cabergoline at dry off can also be used to reduce new intramammary infection rates and improve animal welfare after dry off.

The objective of this study was to assess the efficacy of ketoprofen compared with ceftiofur hydrochloride for the treatment of acute puerperal metritis (APM). Specifically, we set out to compare the incidence of extended treatment (extT) between treatment groups, to determine the prevalence of purulent vaginal discharge (PVD) and milk yield on the first 3 milk tests postpartum, and to analyze reproductive performance of cows treated with ketoprofen or ceftiofur. Cows with rectal temperature ≥39.5°C and reddish-brown fetid vaginal discharge within the first 10 d in milk (DIM) were diagnosed with APM. Day of enrollment and first day of treatment was considered study day 1. Rectal temperature was recorded daily until study day 7. A total of 610 dairy cows with APM were enrolled in this randomized clinical trial. Cows meeting the inclusion criteria were allocated to treatment with ketoprofen (3mg/kg of body weight, n=300) or treatment with ceftiofur (1mg/kg of body weight, n=310) on study days 1, 2, and 3. Cows that showed rectal temperature ≥39.5°C between study days 4 and 7 received an extT with ceftiofur for 3 (ketoprofen group) or 2 (ceftiofur group) more days. Cows were examined with the Metricheck device (Simcro, Hamilton, New Zealand) between DIM 21 and 40, and vaginal discharge was categorized on a 5-point scale according to the presence of pus. Cows with a score ≥2 were classified as having PVD. Fifty-two cows (35 from ketoprofen group, 17 from ceftiofur group) were excluded from analysis due to missing protocol compliance (n=37) or concurrent disease (n=15). Cows treated with ketoprofen were more likely to have an extT than cows treated with ceftiofur (61 vs. 31%). Prevalence of PVD did not differ between the 2 treatment groups (ketoprofen, 56%; ceftiofur, 53%). Cows, however, that needed an extT after the initial 3-d treatment were more likely to develop PVD than cows without extT (64 vs. 46%). Treatment group did not affect milk yield (ketoprofen group, 35.5±0.4kg; ceftiofur group, 35.2±0.3kg), first artificial insemination pregnancy risk (ketoprofen group, 20% vs. ceftiofur group, 25%), median days to first artificial insemination [ketoprofen group, 73 d, 95% confidence interval (CI): 70-75 d vs. ceftiofur group, 75 d, 95% CI: 72-76 d] and median days to pregnancy (ketoprofen group, 144 d, 95% CI: 132-158 d vs. ceftiofur group, 133 d, 95% CI: 119-153 d). These results indicate that although cows initially treated with ketoprofen were more likely to receive extT, fewer doses of ceftiofur (1.83) were required compared with cows initially treated with ceftiofur (3.63). Moreover, the prevalence of PVD was not increased and milk yield and reproductive performance were not negatively affected by the initial treatment with ketoprofen.