Calving in double muscled cows: why
cows do not strain abdominally during
parturition and prediction of
parturition
Student: Tom Broeze
Begeleider: dr. Herman Jonker
Tabel of content
Abstract .................................................................................................................................................................. 3
Introduction ............................................................................................................................................................ 4
Materials en methods............................................................................................................................................. 6
Animals and management .................................................................................................................................. 6
Prodromi: the forecast of the moment of parturition ........................................................................................ 6
Behavior .......................................................................................................................................................... 6
Posture............................................................................................................................................................ 7
Physical parameters........................................................................................................................................ 7
Parturition........................................................................................................................................................... 8
Post parturient evaluation of the newborn calf ............................................................................................. 8
Post parturient evaluation of the cow ............................................................................................................ 8
Statistics .............................................................................................................................................................. 9
Prodromi ......................................................................................................................................................... 9
Analysis of the parturition .............................................................................................................................. 9
Results .................................................................................................................................................................. 10
Animals ............................................................................................................................................................. 10
Prodromi ........................................................................................................................................................... 10
Behavior ........................................................................................................................................................ 10
Posture.......................................................................................................................................................... 13
Physiological parameters .............................................................................................................................. 14
Parturition......................................................................................................................................................... 19
Discussion ............................................................................................................................................................. 21
Prodromi ........................................................................................................................................................... 21
Behavior ........................................................................................................................................................ 21
Posture.......................................................................................................................................................... 22
Physiological parameters .............................................................................................................................. 22
Parturition......................................................................................................................................................... 23
Conclusion ............................................................................................................................................................ 25
Prodromi ........................................................................................................................................................... 25
Parturition......................................................................................................................................................... 25
Recommendations ............................................................................................................................................ 25
References ............................................................................................................................................................ 26
Abstract
In this pilot study we looked at the parturition of 14 double mouscled ‘verbeterd roodbont’ cattle on a
commercial farm in the Netherlands. Before parturition we reviewed several clinical and behavioral
parameters to predict the exact time of parturition (1) since this proves to be a difficult matter for a lot of
farmers. During parturition we attempted to find a cause for the lack of abdominal strain that some animals
tended to show when in partu (2) despite the fact that they should be able to deliver naturally according to
size of the calf and size of the pelvis.
1: Cows were monitored every 12 hours before parturition until 12 hours before expected calving, based on
prodromiafter which they were monitored every 4 hours . Rectal temperature showed a drop 24-36 hours
before calving and keeping the tail away from the body proved to be a useful parameters for upcoming
parturition in 1-6 hours as well, also relaxation of the sacrosciatic ligaments, swelling of the udder and restless
behaviour showed some relation (however not significant) with the onset of parturition.
2: The hypothesis of the high birthweight of the calves causing a late onset of straining could neither be
rejected nor confirmed. Only one cow was able to calve per vaginam, most calves were delivered by
Cesaerean Section. However, cows were able to strain abdominally on the appearance of the amniotic sac
indicating that breeders did not unintentionally select on ‘non straining’ animals. Also the number one cause
for lack of abdominal straining in dairy cattle, milk fever, could be ruled out since none of the cows had low
calcium levels within one hour after calving. To confirm the hypothesis’ in this study further research is needed
with more cows and a higher proportion of cows that are able to calve naturally.
Introduction
The objective of every beef cattle farm is to breed calves either for slaughter or for further breeding purposes.
The double muscled cows (i.e. Belgian Blue and Verbeterd Roodbont, translated: Improved Red and White,)
are a type of beef cattle with extreme muscularity, that is known for its exclusive meat quality and high
slaughter weight.
However, in double muscled cows, calving occurs virtually never in a natural way and is performed in most
cases by a Caesarean Section (CS). In double muscled Belgium Blue cows the percentage of cattle calving with
the aid of CS even ranges from 95-99.9% (Kolkman et al. 2007). Despite some differences in behavior between
animals that delivered in a natural way or animals that delivered with the aid of CS, it is still not scientifically
proven that animals suffer more from either one of them (Kolkman et al. 2010). However some ethical
problems may arise in case of gestation and parturition of an animal that most likely cannot deliver its young in
a natural way. There is an increase in resistance among the population of the Netherlands and Europe.
Marianne Thieme (Dutch politician) for example inquired the former minister of agriculture, nature and food
quality on behalf of the ‘Partij voor de Dieren’ about this matter in the House of Representatives in 2008.
Today, there is a trend towards a double muscled breed that is able to calve in a natural way. The ‘Verbeterd
Roodbont’ (VR) breed of cattle is a Dutch beef breed and originates from MRIJ-cows, a dual purpose breed,
having dairy purposes as well as beef. The MRIJ-cows have been developed to a double muscled breed with
solely beef purposes. There are initiatives in the VR sector for more natural calvings and therefore less CS in
this double muscled breed. In the project ‘Natuurlijk luxe’, farmers select their cows and bulls on hereditary
characters like tall cows, especially with a large pelvic cavity (Vereniging Nederlands stamboek verbeterd
roodbont vleesvee, 2012). The determination of the height and width of the pelvis is done with the aid of a
Rice pelvimeter (fig.1). With the pelvimeter the pelvis is measured in the tallest and widest point as described
by Kolkman et al. (2009): after epidural anesthesia the pelvimeter was inserted in the empty rectum under
manual guidance. Then, the pelvic height was measured by opening the device within the pelvic canal between
the pubic symphysis and the sacral vertebrae and the pelvic width was measured as the horizontal distance
between the shafts of the ilium at the widest point. These measurements were done three times and the
mean value was further analyzed. The farmer where this study was done also strived to select on small calves
at time of birth.
Fig 1: Rice Pelvimeter (Nasco, Fort Atkinson, Wisconsin)
Farmers that tend to achieve natural calving by selecting suitable animals notice another problem. They now
report a phenomenon which they describe as lack of abdominal straining of the cow when she is in labour. It is
not clear where this phenomenon originates from. In literature there are not so many leads to what causes the
absence of abdominal straining. For instance Gundelach et al. (2009) only found in German dairy cattle that
cows aided with extraction or CS had significantly less abdominal straining than animals that were not.
However several suggestions can be done. One of the most common diagnoses for not straining in dairy cattle
is milk fever, too low blood calcium concentration. This also causes over all muscle weakness in worse cases
and is caused by the huge transition of quantities of milk produced at the end of gestation. Another cause
could be that the calf is too heavy to be brought in the pelvic cavity or it may take longer. Thereby the
Ferguson reflex would be delayed. The Ferguson reflex is a neural-hormonal reflex that releases oxytocin in the
brain when stimulated by pressure in the cervix. One of the effects of oxytocin is contraction of the uterus.
When the uterus contracts too little it will take longer for the calve to enter the birth channel. This way the
stimulation resulting in abdominal straining would be less and the process would take longer. This is a problem
in the judgment of the progress during calving in double muscled cows and may influence the moment of
intervening. A third possibility, suggested by some breeders, may be that the animals are, unintentionally,
selected on their disability to push.
The consequences of dystocia during calving are often stillbirth (Mujibi and Crews Jr., 2009). Citek et al. (2011)
did research towards obstetrical problems in various cattle breeds. They investigated 5970 calvings among
different breeds and found in general 4.29% of the cows suffered dystocia. This resulted in 70.31% in stillbirth
whereas the stillbirth in calvings with a normal course is only 4.15%. In beef cattle the percentage of dystocia is
much higher than in dairy cows. (Mujibi and Crews Jr., 2009) investigated the percentage of Charolais that is
able to calve in a natural way. They found a percentage of 83%, meaning 17% of the Charolais in the study
suffered dystocia. 70% of the dystocia cases resulted in stillbirth.
To be able to assist in time in cases of dystocia, it is very important for preventing complications with the calve
as well as with the cow to predict the time of calving as accurately as possible. Various attempts have been
made to establish a model for predicting calving time accurately in dairy cattle (Miedema et al. 2011; Streyl et
al. 2011; Wehrend et al. 2006; Huzzey et al. 2007). This appears to be a difficult matter. There are many
differences between individual cows. Furthermore the time of parturition needs to be estimated relatively
precise: normally the parturition ranges from 1 up to 6 hours (Syllabus: voorplanting en obstetrie, 3e jaar
Bachelor, faculteit diergeneeskunde Utrecht) or 2-6 hours according to Senger (2003). The farmer needs to
know relative precise when the parturition starts because the chances on stillbirth and less vital calves
increase when the parturition takes longer (Syllabus: voorplanting en obstetrie, 3e jaar Bachelor, faculteit
diergeneeskunde Utrecht). However, based on the experience of several farmers, predicting calving time in
double muscled beef cattle proves even more difficult than in dairy cattle. Therefore an attempt has been
made to establish a model for predicting the time of calving.
This study had two aims: one was to find parameters to predict the time of calving more accurately in double
muscled cows. The other one was to study the course of parturition and the occurrence of abdominal straining
in calving double muscled cows.
Materials en methods
Animals and management
The study was conducted during February 2012 among a group of 14 VRB cattle in the Netherlands. The farm
was selected because the owners tended to let their cows calve in a natural way and had succeeded several
times. This would provide natural calving animals as well as animals with dystocia for statistical analysis.
All animals in the study where so called ‘double-muscled’ cows, named after their genetically determined
extreme muscularity. The cows were normally held in a nature reserve in a herd of approximately 30 animals.
Around calving they were kept in tie-stalls, thus they were tethered by neck chains during the study.
Exceptions were two cows which were held in boxes with straw bedding. The cows were brought in when the
farmer saw some changes in physiology of the cow. The decision was based mainly on changes of the udder
(i.e. reddening, growing and filling of the udder) and general behavior. When these two parameters started to
change the decision was made to bring them in. Another criterion taken in to account was the day of
parturition based on the estimated gestation length during a pregnancy check by a veterinarian at
approximately 3 months gestation.
The feeding regimen consisted of grass silage in the morning and evening, and concentrates and bread only in
the morning. However, two cows were fed with hay instead of silage due to their relative bad conditions.
The cows were allowed to drink water ad libitum. However until the 15 th of February (i.e. during approximately
the first half of the study) the cows were only allowed to drink ad libitum water twice daily, due to an
extremely cold period where temperatures reached -22°C which froze the water supply system.
The temperature in the stalls was highly dependent of the weather. And despite they were not measured the
estimated conditions varied from minus 5 degrees to 10 degrees Celsius.
Prodromi: the forecast of the moment of parturition
The cows were monitored from the day they stood in the tie-stalls. Every twelve hours the cows were
observed by the same observer. Based on the criteria published by Wehrend et al. (2006) who did research to
parameters that would indicate dystocia in dairy cattle and (Miedema et al. 2011) who established a protocol
for determining the moment of parturition in dairy cattle, the animals were monitored on the following
parameters twice daily during a 15 min period:
Behavior
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Restlessness: Cows were monitored for frequency in change of behavior and overall nervousness for
one quarter of an hour and scored on a 1-3 scale: 1 being very calm, 2 slightly restless with frequent
change of activities and laying/standing bouts and 3 very restless with frequent change of activities
and laying/standing bouts and permanent interruption of behavior in the case of the slightest
environmental change.
Dragging leg while laying down: Cows were monitored for the frequency of dragging with a hind leg
while laying down. This was not based on Wherend et al. (2006) but the farmer tended to monitor
this behavior which would in her experience increase when approaching parturition.
Scraping and stamping: Cows were monitored for frequency of scraping and stamping. Only the
stamping and scraping in the last 36 hours before calving was conducted in this study. Only 8 cases of
(repeated) stamping were observed of which 5 occurred with the same cow. Hence, no relation could
be found and it was not used in further analysis.
Vocalization: Cows were monitored for frequency of vocalization during fifteen minutes. Only 2 cases
of vocalization were observed, therefore no pattern could be discovered as the parturition
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approached. Despite the fact that the vocalization occurred in cases close to parturition it was not
included in the statistical analysis of this study.
Food intake: Cows were monitored for duration of eating. Despite the attempts to monitor the
animals on a regular time (before feeding) this was not always possible.
Water intake: Cows were monitored for duration of drinking. However drinking could not be analyzed
in this study since the animals were allowed to drink water only twice daily. This because of an
extremely cold period which caused a malfunctioning water supply system and that lasted for more
than half the period of this study.
Ruminating: Cows were monitored for duration of ruminating.
Rubbing/scratching + skin condition: Cows were monitored for frequency and duration of rubbing. In
addition condition of the skin was scored on a scale of 1-3 (1 meaning no visible skin lesions, 2 few,
little affected skin, 3 severe affected skin). None of the cows had a serious skin condition and were
thus scored a 1 except for one cow which had lice and was therefore scored a 3.
Grooming: Cows were monitored for frequency and duration of grooming. Since only 7 cases of
grooming were observed it was excluded from further analysis in this study.
Urinating: Cows were monitored for frequency and duration of urinating. Since there were too few
cases of urinating (6) observed it was excluded from further analysis in this study.
Defecating: Cows were monitored for frequency and duration of defecating. Since there were too few
cases of defecating (5) observed it was excluded from further analysis in this study.
Walking: Miedema et al. (2011) found that Simmental cows within twelve hours before parturition
would spend less time on walking than cows in which parturition was more than twelve hours away.
However we could not investigate this behavior in this study since the cows stood in tiestalls.
Wehrend et al. (2006) describes that the animals separate themselves from the group when
parturition is at hand. Animals were held in tiestalls. Therefore they could not separate themselves.
Posture
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Keeping off tail: Scored was if the cows kept their tail distant from their bodies on a 1-3 scale. 1 tail
against body, 2 tail slightly away (approximately 10 degrees), 3 far off (more than 10 degrees).
Arching back: Cows were monitored for frequency and duration of arching of the back during fifteen
minutes. Since there were only 3 cases of arching back observed it was not included in the statistical
analysis of this study.
Laying and standing: Cows were monitored for duration of laying down and standing up.
Physical parameters
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Movement of the rumen: The frequency of movements of the rumen was monitored during 3 min.
Further, the strength and length of the contractions was determined and noted when considered odd.
Rectal temperature: Measured with a ‘microlife Vet-temp’-thermometer. The thermometer was put
in the rectum until the screen and held there against the intestine wall until it gave a beeping signal.
Broad pelvic ligaments (sacrosciatic ligaments) relaxation: Scored on a scale from 1-5. 1 being
completely stiff/bonelike and 5 being completely relaxed/hardly or not palpable.
Swelling of the vulva: Scored on a scale from 1-5. 1 being wrinkled and not swollen and 5 being
extremely swollen and tense.
Color of the vulva: The color of the vulva was not conducted in this study. There was hardly any
variation visible between cows approaching parturition and cows far off.
Udder development: Scored on a scale from 1-5. 1 being small (relative to age and parity) and pale
and 5 being big and with pink teats.
Filling of the udder: Scored on a scale from 1-5. 1 being empty, 4 being filled with poor teat filling and
5 being filled completely
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Udder edema: The cows were monitored for edema in the median suspensory ligament and under
the belly. Since no correlation could be indicated, either with the help of a graph or with the aid of
correlation analysis in SPSS v.20, edema around the udder was not included in the statistical part of
this study.
Vulva secretion: length measured in cm. Since no correlation could be indicated, either with the help
of a graph or with the aid of correlation analysis in SPSS v.20, secretion from the vulva was not
included in the statistical part of this study.
Breathing frequency: determined at sight and with a stopwatch during 15 sec. Since no correlation
could be indicated, either with the help of a graph or with the aid of correlation analysis in SPSS v.20,
breathing frequency was not included in the statistical part of this study.
Pulse frequency: measured during 15 sec with the aid of a stethoscope and a stopwatch. Since no
correlation could be indicated, either with the help of a graph or with the aid of correlation analysis in
SPSS v.20, pulse was not included in the statistical part of this study.
The frequency of the observations was increased to every 4 hours when the estimated time until parturition,
based on prodromi and the expertise of the farmer and the observer, was expected to be less than 12 hours.
Parturition
The cows in parturition were observed for:
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First occurrence of abdominal straining: Noted was how often and how long the abdominal strain
occured. A score on a scale of 1-3 was given (1: no pushing, 2:not long and/or often enough, 3:
pushing).
Tone on uterus: The tonus on the uterus was determined by vaginal exploration and/or during the CS
through the incision. A score on a scale of 1-3 was given (1: little tone, 2: moderate tone, 3: firm,
much tone).
Appearance or breaking of the amniotic sac: Noted was when the amniotic sac appeared and broke.
Appearance of the legs: Noted was when the (front)legs appeared.
Appearance of the head of the calf: Noted was when the head appeared.
Time of birth: Noted was when the calf was completely delivered.
However, appearance of the amnion sac, appearance of the legs, appearance of the head and time of birth
were not conducted in this study since there was only a single natural parturition. At time of calving the
decision was made whether or not a CS would be performed. When it was decided to perform a CS, the cow
was placed in a specifically designed CS box and the CS was performed by a local vet.
Post parturient evaluation of the newborn calf
Noted was whether the calf was dead or alive. In case of the latter it was examined for an APGAR-score, which
consists of determining breathing frequency, pulse frequency, color of the mucous membranes, inter digital
claw reflex and muscle tone. The APGAR-score was determined twice: directly after birth (within 3 minutes)
and about 15 minutes after birth. Further bodyweight, circumference of the phalanx and the shank, and time
to sternal recumbency, standing and drinking were determined. However the APGAR-score would serve as an
indication of the course of the partus (light or heavy) in case of a natural calving. Since there were too few
cases of natural calving evaluation of the calf was not analyzed in this study.
Post parturient evaluation of the cow
Within an hour after calving a blood sample was taken from the cow out of the tail artery/vein. The blood was
then left standing for a few hours until the serum was separated from the blood cells. After that the plasma
was collected and frozen. At the end of the study the progesterone and calcium levels were determined in all
the samples.
The first two days postpartum the cow was monitored every 12 hours and scored on the thickness of the
vulva, excretions of the vulva and color of her vulva and her rectal temperature was measured. Also expulsion
of the placenta was monitored. These findings were not conducted in this study for their purpose was to
estimate the difficulty of the natural parturition. There was too little information on natural calving cows since
only one cow calved in a natural way.
Statistics
Prodromi
Time until parturition was classified in time blocks: 0-6 hours, 7-12 hours, 13-24 hours, 25-36 hours, 37-48
hours, 49-60 hours, 61-72 hours, 73-84 hours and 85-96 hours.
At first the data were checked for usefulness. Four cows were not included in the statistical analysis because
there were too little observations for them to be useful.
After that for each parameter was determined, with the aid of a graphic and determination of the correlation,
whether or not they would be useful in further statistical analysis. The graphics were build in Microsoft Excel
2007 and the correlations were determined in SPSS v.20.0. The graphics were simple plots with the parameter
on the X-axis and the time until parturition on the Y-axis. The data used were of the individual cows as well as
means for all cows.
The statistical analyses were performed in SPSS v.20.0. For the continuous as well as the ordinal predictors the
linear mixed model was attempted. However, due to too little observations the statistical analysis was
excluded and a diagram could only indicate whether a relationship existed or not.
Analysis of the parturition
No statistical analysis could be done with the data from cows in parturition since no comparison could be
made between the group calving with aid of a caesarean section and the group calving naturally. However with
the aid of diagrams and comparisons with findings in literature several assumption could be made.
Results
Many of the results were not statistically significant, partially due to a low number of animals. However,
keeping off of the tail and a drop in rectal temperature could be identified as significantly relevant indicators
for the onset of calving.
Other factors, including restlessness, weakening of the sacrotuberous ligaments and development of the
udder, appeared change when calving approached but statistically they were not significant.
Animals
Table 1 is a summary of the parity, age of the cow, whether or not they pushed during parturition, tone on the
uterus and the gender and birth weight of the calf. Also the concentration of progesterone (P4) (ng/ml) and
calcium (ml/l) is presented.
Only three animals had calved before. There were seven animals that did not push, also six animals had to low
tone on the uterus. No abnormalities were seen in calcium levels. In progesterone levels one cow with a dead
fetus showed an elevated P4 level.
Cow
Parity
Age
Pushin
Tone on
Gender Weight
Serum calcium Serum proges(years) g (1-3)
uterus (1-3)
calf
calf (kg)
(ml/l)
terone (ng/ml)
A
1
2
3
3
Male
45
2,14
0,4
B
1
2
1
1
Female 52
2,30
0,2
C
1
2
1
2
Male
46
2,27
0,4
D
1
3
Male
46
E
1
3
3
3
Female 62
F
1
3
2
1
Female 54
G
1
3
3
Male
54
H
1
3
2
3
Male
42
2,55
0,3
I
1
3
1
Female 58
2,20
0,2
J
1
3
1
1
Male
50
2,23
0,4
K
2
5
1
2
Female 53
L
3
6
1
3
Female 56
M
56
2,12
0,5
N
4
8
1
2
Male
42
2,11
5,7
Table 1: Several parameters (parity, age, pushing, tone on uterus, gender and weight of the calf and serum
calcium and progesterone levels) summarized per cow.
Prodromi
3 cows were expelled from the study due to a lack of information which left 11 remaining for further analysis.
Behavior
Restlessness
In figures 2 and 3 the score for restlessness has been plotted during the last 36 hours before parturition. An
increase in restlessness is visible from the last 6-12 hours before parturition. However, it was not statistically
significant.
Restlessness
Cow A
2.5
Cow B
Cow C
2
Cow D
1.5
Cow E
Score (1-3)
Cow G
1
Cow I
Cow J
0.5
Cow K
0
24-36
12-24
6-12
0-6
0
Hours before parturition
Cow L
Cow N
Fig 2: Cows were scored for restlessness on a scale of 1-3 (1: calm, 2: frequent change of behavior, 3:
frequent change of behavior and disruptance of the current behavior at the slight environmental changes)
Restlessness (mean)
1.8
1.6
1.4
1.2
1
Score (1-3)
0.8
0.6
0.4
0.2
0
24-36
12-24
6-12
0-6
0
Hours before parturition
Fig 3: Mean restlessness score. Cows were scored for restlessness on a scale of 1-3. Error bars indicate 95%
CI.
Dragging leg while laying down
Figures 4 and 5 show the frequency of dragging with one of the hind legs during fifteen minutes during the last
4 days before parturition. Due to the wide variation (error bars are overlapping) it was excluded from further
analysis.
Dragging leg while laying down (mean)
2.5
2
1.5
Frequency
1
0.5
0
84- 72- 60- 48- 36- 24- 12- 6-12 0-6
96 84 72 60 48 36 24
Hours before parturition
0
Fig 4: Cows were monitored for dragging with their legs while laying down during 15 minutes. Error bars
indicate 95% CI.
Food intake
No relation was found between eating and the onset of parturition and showed a wide variation. Eating was
not further analyzed.
Food intake (mean)
12
10
8
6
Minutes
4
2
0
24-36
12-24
6-12
0-6
Hours before parturition
0
Fig 5: Cows were monitored for food intake during 15 minutes. Error bars indicate 95% CI.
Ruminating
No pattern could be seen for ruminating in relation to parturition (figure 6). Ruminating was not included in
the statistical part of this study because of the wide variation.
Ruminating (mean)
14
12
10
8
Minutes
6
4
2
0
24-36
12-24
6-12
0-6
Hours before parturition
0
Fig 6: Cows were monitored for ruminating during 15 minutes. Error bars indicate 95% CI.
Rubbing/Scratching
Since no relation could be indicated with the help of a scatterplot and variation is wide, scratching was not
further analyzed.
Rubbing/Scratching (mean)
4
3.5
3
2.5
Frequency 2
1.5
1
0.5
0
24-36
12-24
6-12
0-6
0
Hours before parturition
Fig 7: Cows were monitored for rubbing/scratching during 15 minutes. Error bars indicate 95% CI.
Posture
Keeping tail off
Animals kept their tail off more in the last hours before calving. With the aid of an ANOVA-test was
determined that there was a significant difference (P<0,05) in keeping the tail off in cows just before calving
(<0 hours) and longer away from calving (>6 hours) (figure 8).
Keeping of tail (mean)
2.5
2
1.5
Score (0; 1
or 2)
1
0.5
0
24-36
12-24
6-12
0-6
0
Hours before parturition
Fig 8: Average score of keeping tail off. Cows were scored for the degree of keeping their tail of their body.
Error bars indicate 95% CI. Time 0 significant different from the previous time points (P< 0.05)
Laying/ standing
Only standing in the last 36 hours before calving was conducted in this study. However, there was no relation
visible with the aid of a scatterplot and it showed wide variation (figure 9).
Standing (mean)
18
16
14
12
Minutes
10
8
6
4
2
0
24-36
12-24
6-12
0-6
0
Hours before parturition
Fig 9: Cows were monitored for standing during 15 minutes. Error bars indicate 95% CI.
Physiological parameters
Findings of several physiological parameters indicated a trend towards a relationship with the onset of
parturition. However, analysis of the data of the data (except for rectal temperature) with linear regression
model in SPSS v.20.0 was not possible due to a lack of data. Because of this, swelling of the vulva, development
of the udder and filling of the udder could also not be analyzed by the linear logistic regression model.
Rectal temperature
When the temperature is measured every 12 hours there is a drop from about -0,5 °C (95% confidence interval
of -0,3 till -0,7) visible between 24 and 36 hours before parturition (model based on observations by Burfeind
et al (2011)). This model was confirmed by the observations in this study. With the aid of an ANOVA test
temperatures close to parturition (less than 24 hours) were determined significantly lower (P<0,05) than those
further off (36 hours or more) (figure 11).
4067.0
Rectal temperature
40
3511.0
4000.0
39.5
4059.0
Degrees
Celsius
39
4064.0
4070.0
38.5
4072.0
38
4073.0
4074.0
37.5
84- 72- 60- 48- 36- 24- 12- 6-12 0-6
96 84 72 60 48 36 24
Hours before parturition
0
9123.0
9124.0
Fig 10: Individual cows rectal temperature measured before parturition.
Rectal temperature (mean)
40
39.5
39
Degrees
Celsius
38.5
38
37.5
8496
7284
6072
48- 36- 24- 12- 6-12 0-6
60 48 36 24
Hours before parturition
0
Fig 11: Average rectal temperature. Cows rectal temperatures were measured.
Weakening of the sacrotuberous ligaments
Visually there seems to be a correlation (0,65, P<0,01) between weakening of the pelvic ligaments and the
time until parturition. With figures 12 and 13 an attempt has been made to visualize this relationship. However
no statistical relation could be proven with the linear mixed model.
Time group antepartum
Score
36-24
24-12
12-6
6-0
0
1
0,30
0,09
0
0
0
2
0,60
0,64
0,33
0
0
3
0
0,27
0,33
0,50
0,40
4
0,10
0
0,33
0,38
0,20
5
0
0
0
0,13
0,40
Fig 12: Overview of the relative score administered per time group. The left column indicates the score, and
the upper row indicates the time until parturition. The remaining numbers represent the percentage of a
certain score relative to the total of observations in the corresponding time group. Darker blue indicates a
higher proportion in that group.
Time group antepartum
Score
36-24
24-12
12-6
6-0
0
1
0,75
0,25
0
0
0
2
0,38
0,44
0,19
0
0
3
0
0,25
0,25
0,33
0,17
4
0,13
0
0,38
0,38
0,13
5
0
0
0
0,33
0,67
Fig 13: Overview of the chance that a certain score for pelvic ligament relaxation belongs in a certain time
group. The left column indicates the score, and the upper row indicates the time until parturition. The
remaining numbers represent the percentage of a certain score in a certain time group relative to the total
number of this score. Darker blue indicates a higher proportion in that group.
Weakening of the sacotuberal ligaments (mean)
5
4.5
4
3.5
3
Score 2.5
2
1.5
1
0.5
0
24-36
12-24
6-12
0-6
0
Hours before parturition
Fig 14: Average score of weakening of the pelvic ligaments. Cows were scored for the degree of weakening
of the pelvic ligaments. Error bars indicate 95% CI.
Swelling of the vulva
Only a very small tendency could be found between time of calving en swelling of the vulva. This was not
significant. Figures 15 and 16 indicate a small correlation on the long term.
Time group antepartum
Score
36-24
24-12
12-6
6-0
0
1
0,00
0,00
0,00
0,00
0,00
2
0,30
0,18
0,11
0,00
0,00
3
0,10
0,27
0,22
0,25
0,40
4
0,30
0,27
0,22
0,38
0,20
5
0,30
0,27
0,44
0,38
0,40
Fig 15: Overview of the relative score administered per time group. The left column indicates the score, and
the upper row indicates the time until parturition. The remaining numbers represent the percentage of a
certain score relative to the total of observations in the corresponding time group. Darker blue indicates a
higher proportion in that group.
Time group antepartum
Score
1
36-24
0,00
24-12
0,00
12-6
0,00
6-0
0,00
0
0,00
2
0,33
0,33
0,17
0,00
0,00
3
0,10
0,20
0,10
0,10
0,10
4
0,25
0,25
0,17
0,25
0,08
0,20
0,20
0,27
0,20
0,13
5
Figure 16: Overview of the chance that a certain score for swelling of the vulva belongs in a certain time
group. The left column indicates the score, and the upper row indicates the time until parturition. The
remaining numbers represent the percentage of a certain score in a certain time group relative to the total
number of this score. Darker blue indicates a higher proportion in that group.
5
4.5
4
3.5
3
Score 2.5
2
1.5
1
0.5
0
Swelling of vulva (mean)
24-36
12-24
6-12
0-6
Hours before parturition
0
Fig 17: Average score of swelling of the vulva. Cows were scored for the degree of swelling of the vulva. The
vertical axis indicates the score on a scale from 1-5, the horizontal axis indicates the time until parturition.
Error bars indicate 95% CI.
Development of the udder
The development of the udder appeared to have a correlation with the approach of parturition (figure 18 and
19). This correlation was 0,32 (P<0,05) when a time frame up to 60 hours was considered. However during the
last days it appears only useful for the prediction of the time of parturition in addition to others, since in 30%
of cows score 5 was already reached 48 hours before calving (figure 18). Also, no statistical relation could be
proven with the linear mixed model.
Time group antepartum
Score
36-24
24-12
12-6
6-0
0
1
0,00
0,00
0,00
0,00
0,00
2
0,00
0,00
0,00
0,00
0,00
3
0,30
0,40
0,11
0,13
0,14
4
0,40
0,40
0,33
0,25
0,14
5
0,30
0,20
0,56
0,63
0,71
Fig 18: Overview of the relative score administered per time group. The left column indicates the score, and
the upper row indicates the time until parturition. The remaining numbers represent the percentage of a
certain score relative to the total of observations in the corresponding time group. Darker blue indicates a
higher proportion in that group.
Time group antepartum
Score
36-24
24-12
12-6
6-0
0
1
0,00
0,00
0,00
0,00
0,00
2
0,00
0,00
0,00
0,00
0,00
3
0,30
0,30
0,10
0,10
0,10
4
0,21
0,29
0,14
0,07
0,07
5
0,15
0,10
0,25
0,25
0,20
Fig 19: Overview of the chance that a certain score for development of the udder belongs in a certain time
group. The left column indicates the score, and the upper row indicates the time until parturition. The
remaining numbers represent the percentage of a certain score in a certain time group relative to the total
number of this score. Darker blue indicates a higher proportion in that group.
Udderdevelopment (mean)
5
4.5
4
3.5
3
Score 2.5
2
1.5
1
0.5
0
8496
7284
6072
4860
3648
2436
12- 6-12 0-6
24
0
Hours before parturition
Fig 20: Average score of development of the udder. Cows were scored for the degree of udderdevelopment.
The vertical axis indicates the score on a scale from 1-5, the horizontal axis indicates the time until
parturition. Error bars indicate 95% CI.
Filling of the udder
Filling of the udder showed a similar tendency (figure 21 and 22) as the udder development but no significant
correlation could be found. There was an increase in the content of the udder closer to parturition. However
this parameter was 48 hours before parturition scored 5 in 40% of the cows (figure 21). Therefore other
predictors should also be taken into account.
Score
1
2
3
4
5
Time group antepartum
36-24
24-12
12-6
6-0
0
0,00
0,00
0,00
0,00
0,20
0,00
0,00
0,00
0,20
0,18
0,22
0,13
0,20
0,45
0,22
0,38
0,40
0,36
0,56
0,50
0,00
0,00
0,00
0,40
0,60
Fig 21: Overview of the relative score administered per time group. The left column indicates the score, and
the upper row indicates the time until parturition. The remaining numbers represent the percentage of a
certain score relative to the total of observations in the corresponding time group. Darker blue indicates a
higher proportion in that group.
Score
1
2
3
4
5
Time group antepartum
36-24
24-12
12-6
6-0
0
0,00
0,00
0,00
0,00
1,00
0,00
0,00
0,00
0,14
0,29
0,29
0,14
0,14
0,29
0,07
0,14
0,20
0,20
0,25
0,20
0,00
0,00
0,00
0,07
0,15
Fig 22: Overview of the relative score for filling of the udder in a certain time group in relation to the total
number of this score in all time groups. The left column indicates the score, and the upper row indicates the
time until parturition. The remaining numbers represent the percentage of a certain score in a certain time
group relative to the total number of this score. Darker blue indicates a higher proportion in that group.
Filling of the udder (mean)
5
4.5
4
3.5
3
Score 2.5
2
1.5
1
0.5
0
24-36
12-24
6-12
0-6
0
Hours before parturition
Fig 23: Average score of filling of the udder. Cows were scored for the degree of udderfilling. The vertical
axis indicates the score on a scale from 1-5, the horizontal axis indicates the time until parturition. Error bars
indicate 95% CI.
Parturition
Only one cow did not calve with the aid of a caesarean section, i.e. together with the local vet an attempt was
made to deliver the calf per vaginam. However, much assistance was needed during parturition and in the end
it proved to be a wrong decision for the calve did not survive. Therefore this parturition could not be
considered as completely natural since both the cow needed assistance and parturition was so heavy the calve
did not survive.
Hence, a comparison between cows able to calve naturally and cows that delivered per CS could not be made
based on the information obtained in this study.
As all alive calfs were born by CS the APGAR-score was not evaluated in this study. Its purpose was to relate
the score to the course of the parturition. Since there were no natural parturitions resulting in a living calf the
APGAR-score was of no use for further analysis.
Pushing and birth weight
Five of the 12 cows showed abdominal straining after the amnionsac broke. Based on the findings in this study
there was no relation between pushing and the birth weight of the calves (figure 24). When corrected for
height of the cow, height and/or weight of the pelvis, parity of the cow no significant correlation could be
found either.
Pushing in relation to birth weight
1
Pushing (1) or no
pushing (0)
0
42
42
45
46
50
52
53
54
Birth weight calf (kg)
54
56
58
62
Fig 24: Relation between (not) pushing and birth weight of the calf. The vertical axis indicates whether the
cow was pushing (1) or not (0) when in labor. The horizontal axis indicates the birth weight of the calf.
Discussion
For the parameters keeping off of tail and rectal temperature a significant relation was shown with the onset
of parturition. Some other indications, restlessness, weakening of the sacrotuberous ligaments and
development of the udder, appeared to have a relationship despite the fact that it could not be significantly
proven. Other factor had showed no relationship. In the studies from Berglund et al. (1987), Huzzey et al.
(2005), Wehrend et al. (2006), Huzzey et al. (2007), Miedema et al. (2011) and Streyl et al. (2011) a stronger
relation was described between the parameters and the onset of parturition that were not proven indicative in
this study. However in the later studies dairy breeds were used.
No risk factors could be identified between animals that were or were not able to calve without assistance.
The main obstacles during this research were the low number of animals that calved naturally (only one),
furthermore this cow needed much help resulting in a stillborn calf. Another factor that had a possibly
negative impact on the study was the extremely cold weather during more than half of the experiment.
Prodromi
Behavior
Possibly due to a low number of animals the variation (as seen in figure 3, 4, 5, 6, 7 and 9) of restlessness,
dragging leg while laying down, food intake, ruminating, rubbing/scratching and standing time was large.
Furthermore the feeding regime was possibly not ideal for measuring this parameter since there was no
constant food supply. The food was given twice daily and despite the attempt to monitor the behavior on the
same moment (i.e. before feeding) this was not always possible. Therefore none of these parameters was a
significant indicator for the onset of parturition.
Despite the fact that there seems to be an increase in restlessness in the average cow we have not enough
evidence to confirm this. Wehrend et al. (2006) found restlessness a predictor for dystocia in cows after the
appearance of the amniotic sacs. Cows which would later suffer dystocia would express more restless behavior
in the second stage of labour. Huzzey et al. (2005) found that standing bouts increased in frequency closer to
parturition (11.7 ± 1.07 bouts/d prepartum and 17.3 ± 1.08 bouts/d around parturition; P = 0.002). The cows
used in this experiment stood in tie stalls while normally they were held in a nature reserve. This might have
affected their behavior concerning the standing and lying bouts. Also the cows were only monitored for 15
minutes concerning their behavior. The average frequency of lying/standing bouts was 17 at most found by
Huzzey et al. (2005) indicating that the average bout lasted for more than an hour. Jensen (2012) found an
increase in activity within six hours of calving.
The farmer relied partially on dragging with the legs as one of the predictors for the onset of calving. We could
not confirm this. Also in literature this parameter is not known.
Miedema et al. (2011) found that Simmental cows within twelve hours of parturition spend less time eating
(control: 63 ± 6.1 min., 12h until parturition:24 ± 3.6 min. P<0.001). This is confirmed by results from other
studies (Houwing et al, 1990; Huzzey et al, 2005; Huzzey et al, 2007, Shirmann et al, 2013). However, we could
not confirm this in the current study. This is probably due to the feeding schedule in which the cows were not
offered feed continuously.
Several cows (2) even continued ruminating during CS. We found it doubtful that this parameter would be
useful as a predictor for the moment of parturition. Houwing et al. (1990) however found that there was a
linear decline in ruminating activity during the last 6 hours before parturition. Schirmann et al. (2013)
however, showed a decrease in rumination time 4 hours before parturition. This was confirmed by a research
done by Pahl et al. (2014) who additionally found that on average, cows stopped ruminating 123 minutes
before calving. However, 3 cows ruminated within 1 hour before parturition.
Rubbing/scratching might help though in the judgment of the course of the parturition: Wehrend et al. (2006)
Found that rubbing behavior was increased in animals that would suffer from dystocia. It may not be a useful
parameter for the prediction of parturition but it might be helpful in predicting the course of parturition.
Wehrend et al. (2006) also discovered stamping and scraping to be a predictor for dystocia in cows after the
appearance of the amniotic sacs. Cows which would later suffer dystocia would express more stamping
behavior in the first stage of labour and thus might be useful in judging whether or not to call a vet. This
behavior was only observed a very few times in the current study. Also, since none of the cows calved in a
natural way with good result all calving can be considered distotic.
Note that one of the cows not included in the analysis of this study showed more vocalization in the last day
towards the end of her gestation. However the same behavior could not be found in any of the other animals.
Although we can’t draw any conclusions on urinating and/or defecating based on this study, we find it
plausible that their frequencies increases and volumes decreases when parturition approaches. It might help
also in the judgement of the course of the parturition: Wehrend et al. (2006) found that frequency of urinating
was increased in animals that would suffer from dystocia.
Posture
There seems to be a correlation between the onset of parturition and keeping off of the tail. However, this
posture change occurs very short before parturition (<6 hours). It is therefore a useful parameter but the cows
need to be monitored at least every 6 hours and possibly even more often. These findings were confirmed by
(Miedema et al. 2011) who found that an increase in tail raising 0-12 hours before calving occurred (control: 7
± 0.9 min., 0-12h before parturition: 95 ± 12.2 min. P<0.001). This change in posture was seen first in heifers 46 hours before calving, cows only showed it mainly in the last 2 hours.
Despite arching of the back was observed in several cases during parturition, we could not find a relationship
with the onset of parturition.
Laying and standing might be more significant in a larger test group, when measured more frequently over a
longer period of time, or in other conditions than a tie stall. Miedema et al. (2011) found a significant
difference in Simmental cows. Laying occurred more frequently in the group within four hours before
parturition. Huzzey et al. (2005) found that standing bouts increased in frequency closer to parturition (11.7 ±
1.07 bouts/d prepartum and 17.3 ± 1.08 bouts/d around parturition; P = 0.002). However the total time
standing did not differ. Jensen (2012) also found that laying bouts occurred more frequently within 6 hours
before parturition.
Physiological parameters
The temperature of the cows measured rectally dropped in all cows but one >0,4°C. However the moment
varied among the animals from 12-36 hours before parturition. On 3 occasions we measured a drop of more
than 0,4°C in cows that did not calve within 48 hours, however this drop in temperature was not consistent
and the next measurement would be ‘normal’ again. Therefore this is a useful parameter to determine time of
parturition but not a very accurate one, it should always be judged in combination with other signs and
consecutive rectal temperate must show a constant drop in temperature during at least 12 hours. Furthermore
the temperature of the cow should be measured at least twice daily which means more work for the farmer.
There seems to be a positive correlation between weakening of the pelvic ligaments and the time until
parturition. The weakening occurred from before 48 hours before parturition but is very useful to estimate the
onset of parturition since the complete relaxation occurs most often within 12 hours of parturition. According
to Berglund et al. (1987) weakening of the pelvic ligaments starts from up to 10 days before parturition and
the mean of complete relaxation occurs 12 hours before calving (fig. 25). Streyl et al. (2011) also found
relaxation of the pelvic ligaments a useful parameter: they found an AUC with the help of ROC analysis of
0,775 (fig. 26).
The swelling of the vulva appears to have a positive correlation with the time until parturition. However this
was more seen in the last days (i.e. last week) than in the last 48 hours. This predictor is particularly useful in
addition to others. According to Berglund et al. (1987) swelling of the vulva starts from up to 15 days before
parturition and the mean of prominent swelling occurs 66 hours before calving (fig. 25). Streyl et al. (2011) also
found swelling of the vulva rather poor: they found an AUC with the help of ROC analysis of 0,666 (fig. 26).
We did not find any relationship between the color of the vulva and the onset of parturition.
The development of the udder appears to have a positive correlation with the time until parturition. However
this was more seen in the last days (i.e. last week) than in the last 48 hours. This predictor is particularly useful
in addition to others. According to Berglund et al. (1987) development of the udder starts from up to 13 days
before parturition and the mean of complete relaxation of the broad pelvic ligaments occurs 2-4 hours before
calving (fig. 25). Streyl et al. (2011) also found development of the udder, relaxation of the ligaments and teat
filling in particular, a useful parameter: they found an AUC with the help of ROC analysis of respectively 0,732,
0,733 and 0,775(fig. 26) all indicating a relative strong relationship.
Fig. 25 : External signs of impendent calving. Estimated means ± standard deviations for cow effects ( ± σ c) in
different parities.(Berglund et al. 1987)
Fig 26: The predictive value of individual clinical signs for predicting calving within 12 hours (Streyl et al.
2011).
Parturition
Based on the findings in this study we could not make our hypothesis on pushing and birth weight plausible
since both cows with heavy calves and small calves did (and did not) push on the calf. Neither could we reject
it because none of the cows calved naturally so there is no guarantee that they would not push again in a
further stadium of parturition. However, all cows but one pushed on the amnion sac indicating that they did
not lose this ability because of unintended selection. The cow that did not push delivered a calf that was
already dead for at least 2 days.
Blood progesterone was normal in all cows considered they were taken very close to parturition. There was
only one exception: a cow with 5,7 ng/ml progesterone in her blood. This was probably due the intrauterine
death of her calf, which occurred an estimated 2 days before parturition since the hairs had started loosening.
Shenavai et al. (2012) did research towards the hormonal mechanisms controlling parturition and used four
cows as a control group (fig. 27).
Fig 27: progesterone levels in relation to parturition (Shenavai et al. 2012)
The normal range of calcium for cows is 2-2,5 ml/l according to DeGaris and Lean (2008). None of the cows had
a value below 2. Therefore clinical hypocalcemia (<1,4) as well as subclinical hypocalcemia (1,4-2 ml/l) can be
excluded as possible causes for not pushing.
Conclusion
Prodromi
In conclusion we can state that predicting the time of calving can be partially determined by various
physiological parameters. Of these we found the drop in temperature, the weakening of the pelvic ligaments,
development of the udder, restless behavior and keeping of the tail the most useful. However, to make the
best judgment these parameters should be added up.
Especially acting upon rectal temperature alone, like some Belgium farmers tend to do, could result in weak,
premature calves.
However a great factor in predicting the time until parturition is based on the experience and expertise of the
observer. This ‘expert’-factor is also applicable to the parameters stated in the paragraph above since the
score is open for more than one interpretation. It makes the parameters we have used much less distinct.
Still, there remains a indefinite part in predicting the onset of parturition were even an expert has his or her
limits to predict onset of parturition accurately.
Parturition
The question where to look for the reason of a lack of abdominal straining remains unanswered. However we
have no indication it has anything to do with hypocalcaemia. We can also state that the breed is not directly
selected on this disability since most of the cows did push on the amnionic sac, even some that did not push
on the calf later on.
Therefore we still believe that the lack of abdominal straining is caused by (too) heavy calves. It would take
more time to bring the calves into the birthing channel. Since the abdominal straining is stimulated by pressure
in the birthing channel this would then result in an extended parturition. (Schuenemann et al. 2011) found that
after a 80 minute period of time without progress the calving cows needs assistance. However, if our
hypothesis is true 80 minutes might not be long enough for the calf to enter the birthing channel. In this study
the vet was called as soon as the animal was in labor and when became clear that the calf was too big to be
delivered naturally.
Recommendations
For further research on this topic several things could be improved relative to the current study. First of all a
larger number of cows could be of use to increase significance overall and a bigger proportion of cows that are
able to calve naturally is needed to evaluate the lack of abdominal strain. Furthermore, to evaluate the cows
more optimally (especially in case of nest building behavior, separating from the group) cows should not be
kept in a tie stall. To optimally evaluate the feeding system ad libitum feeding is required and the cold during
this period was the cause that the cows could only drink ad libitum during specified times of day. Lastly for
some parameters a better, more accurate value would be obtained when monitored constantly instead of the
certain time intervals chosen in this study (this because of resemblance to the possibilities of a farmer and
from a practical point of view). For example: rumination (Pahl et al, 2014) and feeding (Miedema et al, 2011;
Shirmann et al, 2013).
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