[0001] The invention relates to a device that can be used to assist the cow during calving.
[0002] It is necessary to give help to the animal when delivery is difficult. This is done
by attaching ropes to the legs of the calf. During the cow's contractions, traction
is applied to the calf's legs. The force that needs to be exerted often exceeds the
strength of one person, so the assistance of several people is often required when
helping the cow during calving. Since this is not always possible, there are calving
aids on the market. An appliance of this sort often consists of a support that is
placed against the animal's rear and a traction bar along which a lever mechanism
moves.
[0003] In order to carry out the right actions in all cases during a delivery, a calving
aid should satisfy the following conditions: at all stages of the birth, it must be
possible to apply traction in a controlled manner and it must be possible to pull
in the right direction during the different stages of the birth and in the different
types of birth (forwards or backwards presentation). In addition, since births often
occur at night and the farmer is therefore usually alone, it must be possible for
deliveries to be carried out by a single person. It is also important that the appliance
does not need to be held in place continuously, so that the farmer has his hands free
to carry out other actions that are necessary during a delivery. This is not possible
with existing calving aids. The calving aid that comes closest to satisfying these
requirements is described in patent application
EP0221101. With this appliance, however, it is not possible to exert a sideways force, because
the support not only rests against the rear of the cow but also encloses this. In
this way, it is so completely fixed that traction to the left or right is not a possibility.
The impossibility of moving the traction bar to the left or right of the cow also
has the disadvantage that if the cow is in a small area, there is a safety risk for
the cow or the farmer, since if the cow moves or falls over, the bar can make a striking
movement that cannot be halted. Besides this, although the support is constructed
in such a way that, as described in the patent document mentioned above, the appliance
cannot slide away downwards or sideways, the fact that the point at which the fork
hinges on the support is positioned below the birth canal and the support point, the
traction point (the legs) and the traction mechanism are therefore not in one line
means that the traction bar moves upwards as soon as it is released. On the other
hand, the support has the tendency to slide upwards, so that the birth canal is blocked
by the forked section of the support because in the case of a pulling movement directly
backwards or upwards, the calf is pulled against the fork.
[0004] The purpose of the invention is to provide a construction of the type described above
that does not have the disadvantages mentioned above.
[0005] In the calving aid according to the invention, a fork is attached to the traction
bar along which the pulling mechanism can move backwards. This fork is attached to
the support by two hinges, so that the bar can be moved upwards or downwards and the
traction direction can therefore be adjusted upwards or downwards.
[0006] The support consists of a U-shaped bent tube that rests against the body of the cow,
against the rear and closely surrounding the birth canal of the animal. The top two
ends of the U-shape are bent back so that they rest on top of the cow's back at the
rear. They prevent the support from sliding downwards. The calf moving down the birth
canal causes the canal to bulge slightly and the traction exerted on this pushes the
curve of the U-shape to some extent into the soft areas around the birth canal, the
support is therefore fixed firmly against the rear of the cow and cannot slide away.
Because the support rests against the hindquarters of the animal in the same plane
and unlike the existing constructions as described in the patent document mentioned
above, does not enclose the cow's hindquarters, the bar can also be moved sideways
so that if necessary because of the position of the calf, traction can also be exerted
to some extent in a sideways direction. Moreover, damage is less likely to be caused
to the cow, the assisting operator or the appliance itself if the cow makes an unexpected
movement or suddenly falls down while calving, while because of the tension on the
traction mechanism, as soon as the bar is released, it will automatically return to
the middle position.
[0007] The position of the round pin that forms the rotatable connection between the fork
and the traction bar is such that it forms an angle of about 90 degrees with the plane
of the support if the fork rests against the base of the support while traction is
being exerted. In this way, the birth canal is never completely or partially blocked
by the fork, independent of the position of the bar and therefore of the traction
direction, while the support does not have the tendency to slide upwards because the
support point (the place where the fork hinges on the support), the point where traction
is exerted (the legs) and the traction mechanism are in line with each other.
[0008] Further information is given in the drawings which show a model version of the construction.
[0009] Fig.1 shows the calving aid according to the invention with traction bar (1), the
bent-back ends (3), the vertical support sections (4) the fork (5) and the connecting
pin (6).
[0010] Fig. 2 shows the calving aid as described in patent application
EP0221101 with the hinge where the fork joins the support point (7) below the birth canal and
in which the support point (7), the traction point (8) and the traction mechanism
(9) are not located in the same line.
[0011] Fig. 3 shows the position of the calving aid on the cow during a normal forwards
presentation in which the front legs of the calf emerge first. The U-shaped support
(2) rests against the hindquarters of the cow and in the same plane, with the bent-back
ends (3) resting on the animal's back. The traction direction is straight backwards,
and the connecting pin (6) forms an angle of 90 degrees with the fork (5) so that
the birth canal remains entirely free and the hinge where the fork joins the support
point (10), the traction point (11) and the traction mechanism (12) are located in
the same line.
[0012] Fig. 4 shows the position of the calving aid on the cow for a backwards presentation
in which the back legs of the calf emerge first. In that case, traction is required
in an upwards direction, and the position of the connecting pin (6) ensures that here,
too, the hinge where the fork joins the support point (10), the traction point (11)
and the traction mechanism (12) are located in the same line and the birth canal is
not blocked.
[0013] Fig. 5 shows three views from above, demonstrating that the construction according
to the invention allows traction directions both directly backwards (2) and sideways
in both directions (1 and 3), in which if the appliance is released, it returns to
the straight position.
1. A calving aid for cows in which the support is placed against the rear of the cow
while the traction bar hinges on this by means of a fork, so that traction can take
place towards the tail and towards the udder, characterised in that the support (2) on which the traction bar (1) hinges by means of the fork (5) is
supported on three sides closely surrounding the birth canal against the rear of the
cow, while the upper side of the support remains open and the two ends of the support
pointing upwards are bent forwards (3) and therefore rest on the top of the hindquarters
of the animal, so that the support (2) cannot slide downwards, while because the vertical
sections of the support (4) are supported close to the birth canal and in the same
plane as this, the traction bar (1) can also be moved to the left and the right.
2. A calving aid in accordance with claim 1 characterised in that the round connecting pin (6) that forms the rotatable connection between the fork
(5) and the traction bar (1) forms an angle of about 90 degrees with the plane of
the rear of the cow when the appliance is in place and the fork (5) rests against
the base of the support (2), so that irrespective of the position of the traction
bar (1), the birth canal is not blocked and the hinge where the fork joins the support
point (10), traction point (11) and the traction mechanism (12) are always in the
same line, so that the traction bar behaves neutrally and the support does not slide
upwards.
REFERENCES CITED IN THE DESCRIPTION
This list of references cited by the applicant is for the reader's convenience only.
It does not form part of the European patent document. Even though great care has
been taken in compiling the references, errors or omissions cannot be excluded and
the EPO disclaims all liability in this regard.
Patent documents cited in the description