AHEAD IN ANIMAL HEALTH
128
Monitoring of biotin concentrations in bulk milk in Dutch dairy herds Saskia van der Drift, Marian Aalberts, Menno Holzhauer, Laurie Bruinsma, Bert Koppejan and Jet Mars Royal GD, Deventer, The Netherlands
Aim of the study Biotin is a B vitamin important for milk production and claw health of dairy cows. GD offers a voluntary bulk milk monitoring program to help farmers to improve claw health. This program includes routine analysis of biotin concentrations to indicate the biotin status of dairy herds. The objective of this study was to describe the variation in biotin concentrations in bulk milk across Dutch dairy herds in a two-year monitoring period.
• November
• February
Materials & Methods
• Descriptive statistics are shown in Table 1, Figure 2 and Figure 3. • Biotin concentrations were <30 µg/L in 39,6% of the samples. • Large variation existed between farms (Table 1). • The within-herd coefficient of variation of biotin concentrations in bulk milk was on average 56,0% (range 3,8% - 149,3%).
Conclusion • Monitoring of biotin concentrations in bulk milk using an automated ELISA procedure can support optimization of the biotin status and improve claw health of dairy herds.
Q3 20/21
Q2 20/21 • May
Figure 1: Sampling scheme bulk milk samples for the voluntary monitoring program to improve claw health (including the analysis of biotin concentrations).
Table 1: Descriptive statistics of biotin concentrations in 4824 bulk milk samples from 630 herds.
Biotin (µg/L)
N
Mean
SD
Median
IQR
Min*
Max*
All samples
4824
57.8
48.1
39.0
21.0 – 81.0
15.0
200.0
Herd averages
603
57.8
32.5
51.5
31.9 – 76.3
15.6
195.6
*The minimum and maximum biotin concentration in individual samples represent the limits of the measurement range of the assay.
600
500
Frequency
Results
Q1 20/21
• August
400
300
200
100
0 0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
170
180
190
200
Biotin concentration in bulk milk (µg/L)
Figure 2: Frequency distribution of biotin concentrations in 4824 bulk milk samples from 603 Dutch dairy farms analysed in 2020 en 2021.
Biotin concentrations bulk milk (µg/L)
• Data from dairy herds participating in the program from Q1 2020 until Q4 2021 were selected. • From these herds, bulk milk was sampled four times per year (Figure 1). • Biotin concentrations were assessed in duplicate in skimmed bulk milk samples using a quantitative competitive ELISA in an automated procedure. • Acceptance criteria were set for duplicate results and, if valid, mean duplicate results were reported. • The measurement range of the biotin assay was 15 - 200 µg/L. • A cut-off value of <30 µg/L, based on earlier studies, was used to indicate a suboptimal biotin status. • Only complete herd records were included in the dataset. • Final dataset: 4824 observations from 603 farms. • Descriptive statistics were performed using Statistix.
Q4 20/21
220 200 180 160 140 120 100 80 60 40 20 0 2020 Q1
2020 Q2
2020 Q3
2020 Q4
2021 Q1
2021 Q2
2021 Q3
2021 Q4
Year - Quarter
Figure 3: Biotin concentrations in bulk milk samples from 603 Dutch dairy farms analysed in every quarter during 2020 en 2021. Boxes represent median and interquartile range; whiskers include all cases except outliers (asterisks) and extreme cases (circles).
j.mars@gdanimalhealth.com www.gdanimalhealth.com
GD2685/09-22