Kamphuis & huijps, ECPLF, milan, 2015 ss
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Transcript of Kamphuis & huijps, ECPLF, milan, 2015 ss
Using successful inseminations to evaluate
sensitivity of automated heat detection systems
Claudia Kamphuis, WURKirsten Huijps, CRV
Challenges of detection-Time consuming-Error prone-Increased herd sizes
The importance of heat detection
New Zealand survey 500 farmers25% wants it7% has it70% listed it in top 3 of technologies that gained benefit for farm(Edwards et al., 2014, APS)
Survey 212 farmers stating to have sensor technology41% of AMS farmers has it70% of CMS farmers has it(Steeneveld and Hogeveen, 2015, JDS)
Survey 109 farmers globally41% has itRated as useful to very useful(Borchers and Bewley, 2015, JDS)
35% of US respondents(Bewley, 2014, EAAP/EU-PLF conference)
Adoption rates
What are the success factors?
Associated with clear management actions
What are the success factors?
Associated with clear management actions
Investment is economically beneficial (Rutten et al., 2014)
for Dutch circumstances
What are the success factors?
Associated with clear management actions
Investment is economically beneficial (Rutten et al., 2014)
for Dutch circumstances
Sensitivity 80% with specificity 95% (Rutten et al., 2013, JDS)
performance is OK
But a specificity of 95%....
Still requires visual confirmation
701-05-2023
But a specificity of 95%....
Still requires visual confirmation
100 cow herd:~1 cow in heat / day99 cows not in heat / day5 falsely alerted cows / day
801-05-2023
Alerts around P4 determined heat events(Kamphuis et al., 2014, EAAP/EU-PLF, Copenhagen, Denmark)
84% of all alerts generated +/- 3 days around P4 heatOnly 30 P4 heats included
Use successful inseminations
Avoid high costs and intensiveness of P4 method
Relatively easy way to increase numbers
Additional: study differences in performance between parities and lactation stages
Data collection: January-July 2014
Insemination data from CRVHeat alert data from systems’ software
Farm A Farm B
Herd size 450 250
Milking system Conventional AMS
Milk production (kg/cow/year)
9,500 9,800
Heat detection system A and B B and C
Defining successful inseminations
For cows with just 1 insemination
31 July1 January
Insemination>56 d
Successful GS+
Defining successful inseminations
For cows with >1 insemination
Insemination
>56 d
Successful GS+
Insemination
≤56 d
Unsuccessful
31 July1 January
Insemination
≤ 56 d
Unsuccessful
Insemination
>56 d
SuccessfulGS+
Insemination
≤56 d
Unsuccessful
1 January 31 July
Matching inseminations with alerts
Insemination data at daily level
Heat alerts per h or per 2h time blocks‘summarized at daily level’≥1 alert per day is an alerted day
Data collection: January-July 2014
Farm A Farm B
Herd size 450 250
Milking system Conventional AMS
Milk production (kg/cow/year)
9,500 9,800
Heat detection system A and B B and C
Cows with ≥1 successful inseminations
145 119
GS positive inseminations
153 129
Heat alerts A: 352B: 532 B: 117
C: 887
Matching inseminations with alerts
Sensitivity using a 1 day time-window
GS+
day
Matching inseminations with alerts
Sensitivity using a 2 day time-window
GS+
day
Detection performance differed between heat detection system
Sensitivity (%)A: 31B: 58C: 92
Detection performance differed between heat detection system
Sensitivity (%)A: 35B: 87C: 94
Detection performance did not differ between parity / lactation stage
Sensitivity 2 day time- window
System A System B System C
Parity
1 23 85 90
2 48 90 97
≥3 36 90 94
Lactation stage
≤56 days 44 100 91
>56 days 34 87 94
Discussion / conclusion
Lower performance of System A• consistent with EAAP/EU-PLF 2014• technical problems in data exchange
Discussion / conclusion
Lower performance of System A
Sensitivity may be overestimatedSummarizing h / 2h alerts to daily alertsexcluding data from cows that were
not detected by a systemnot visually confirmed by farmerinseminated incorrectlynot inseminated at all
Discussion / conclusion
Sensitivity in line with previous research (Rutten et al., JDS, 2013)
around 80-90% using a 2 day time-window
System C also alerts often 1 day after a successful insemination
No apparent differences in parity/lactation stageno apparent need for specific algorithmsfocus on getting more accurate and precise alerts
Ongoing data collection
Confirm or refute current findings statistically
Analyze data using hourly or 2hourly alert basis
Where to from here
Thank you for your attention
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