estrus detection dr. ray nebel dept. of dairy science virginia tech
TRANSCRIPT
Estrus DetectionEstrus Detection
Dr. Ray NebelDept. of Dairy Science
Virginia Tech
Estrus DetectionEstrus Detection
Estrus BehaviorEvaluation of Estrus DetectionFactors Affecting Estrous
BehaviorMethods to Enhance Efficiency
of Estrus Detection
Estrous BehaviorEstrous Behavior
Primary sign of estrus– “Standing to be mounted”
Secondary signs of estrus– Attempting to mount other cows– Mucous discharge – Swelling & reddening of the vulva– Restlessness, bellowing, chin
resting, trailing other cows
What Causes Cows to What Causes Cows to Express Estrus? Express Estrus? High blood level of estrogen in
presence of a low level of progesterone– pre-ovulatory follicle in absence of a
functional corpus luteum Involuntary expression
– edema & hyperemia of vulva, mucus secretions
Voluntary expression– Influenced by environment
Days of the Estrous Cycle
-4 -3 -2 -1 Estrus 1 2 3 4 onset ovulation
walking
Time eatingmilk yield
Mounting activity
Standing to be mounted
Variation in Estrus Variation in Estrus ActivityActivity Beef heifers: 16 8 h 60 19 std Dairy cows:
– Holstein: 7 7 h 7 7 std(17 Herds) 7 5 h 9 7 std
– Jersey: 8 5 h 10 7 std Dairy heifers:
– Holstein: 11 7 h 17 7 std– Jersey: 14 6 h 30 17 std
(Duration) ( Intensity)
Factors Affecting Estrus Factors Affecting Estrus BehaviorBehavior Influence of Herdmates Environmental Temperature Footing Surface Foot and Leg Problems Nutrition and Level of Milk
Production
Calving IntervalCalving Interval
Days to First Service– Breeding Season– Max. Number of Services
Estrus Detection
Conception Rate
Evaluation of Estrus Evaluation of Estrus DetectionDetection
Pre-Service
Post-1st Service
Pre-service Estrus Pre-service Estrus Detection EfficiencyDetection Efficiency
Days in estrous cycle
((Days 1st Service - VWP) + 11)
21 (95 - 55) + 11
X 100
X 100 = 41.2%
Post-1st Service EstrusPost-1st Service Estrus Detection Efficiency Detection Efficiency
(S/P-1) (ADO - DFS) 21
(2.5 - 1) (146 - 95) 21
X 100
X 100 = 61.7%
Characteristics of Herds Characteristics of Herds with Inefficient Estrus with Inefficient Estrus DetectionDetection Very few estrus periods observed
or recorded before first service Average days to first service
greater than 20 days beyond the VWP
Excessive interval between services. Average interestrual interval greater than 30 days.
Characteristics of Herds Characteristics of Herds with Inefficient Estrus with Inefficient Estrus DetectionDetection More than 15% of the cows
open at pregnancy examination 35 to 45 days
Palpation confirms cows are cycling normally but estrus periods are not detected
Less than 50% heats observed on DHI 202 Herd Summary
Seasonal effects on the duration of estrus (h) inHolstein and Jersey heifers and cows.
0
2
4
6
8
10
12
14
Dec.-Feb. March-May June-Aug. Sept.-Nov.
Me
an
Est
rus
Du
rati
on
(h
)Cow sHeifers
Seasonal effects on standing activity for cowsby breed.
0
2
4
6
8
10
12
14
Dec.-Feb. March-May June-Aug. Sept.-Nov.Me
an
No
. of
Sta
nd
ing
Eve
nts
HolsteinsJerseys
Seasonal effects on standing activity for heifers
by breed.
0
5
10
15
20
25
30
35
40
Dec.-Feb. March-May June-Aug. Sept.-Nov.
Mea
n N
o. o
f S
tan
din
g E
ven
ts
HolsteinsJerseys
Estrus Detection AidsEstrus Detection Aids
Record systems and estrus expectancy chart
Pressure-sensitive mount detectors– Kamar and Beacon
Tailhead chalk, paint, or crayon Estrus-detector animals
– vasectomized or surgically altered bulls, androgenized females
Automated Estrus Automated Estrus Detection SystemsDetection Systems 24-h continuous surveillance Accurate and automatic identification of
cows in estrus Operational for productive life of the
cow Reduce or eliminate labor requirements Highly accurate ID of estrus
– Senger, 1994
Available Estrus Detection Available Estrus Detection SystemsSystems Pedometry
– Integrated with milking system
– Walking activity increases 2 to 5 times
– Compared to within cow baseline within defined period of time
HeatWatch– electronic
pressure sensing system
– Radio Frequency Data Transmission
– Transmitter/sensor glued to tailhead
– Software - “standing list”, “suspect list”, individual cow files
HeatWatch®
Configuration
HWHW
TransmitterReceiver
Buffer
RepeaterHWHW
When is the beginning When is the beginning of Standing Heat!?of Standing Heat!?
Why is it important to know the beginning of standing heat?
How many times per day are cows visually observed?
Ova viability
24 - 32 h
Onset of Estrus Ovulation
Sperm Viability
12 to 30 h
8 to 12 hsperm transport
6 h
Timing of AI for Dairy Timing of AI for Dairy Cows ID in Estrus by Cows ID in Estrus by HeatWatch SystemHeatWatch System
Interval from first standing event to AI
%Pregnant
2661 inseminations, 17 herds
Time of first standing event (estrus onset) for Holstein and Jersey cattle as determined by the
HeatWatch® estrus detection system
21%
27%
31%
21%
24%
30%22%
24%
00:00-
06:00
12:00
12:00-
18:00
18:00-
24:00
18:00-
24:00
12:00-
18:00
06:00-
12:00
00:00-
06:00
06:00
31%
21%
21%
27%
24%
22%30%
24%
Timing of InseminationTiming of Insemination
HeatWatch – 5 to 16 hrs after 1st stand
Frequency of visual observation– Every 4 to 6 hours “AM-PM”
guideline– Twice or less daily - within 6 hrs
Management Management Requirements for Requirements for Enhanced Estrus DetectionEnhanced Estrus Detection Improved Cow ID Cow Interaction Nutrition & Health Provide Good Footing Surface Utilize Records Employee Responsibility Establish an Aggressive Program
If a Cow is Mounted and No One Sees It, Did It Happen?