Classifications

• • A—HUMAN NECESSITIES
  • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
  • A01J—MANUFACTURE OF DAIRY PRODUCTS
  • A01J5/00—Milking machines or devices
  • A01J5/013—On-site detection of mastitis in milk
  • A01J5/0133—On-site detection of mastitis in milk by using electricity, e.g. conductivity or capacitance

Definitions

• the invention relates to a method of detecting mastitis in cows by means of a mastitis detector of the flow type which includes a measuring unit with a measuring chamber for each cow's teat with inlet and outlet openings allowing passage of milk from the cow's teat, said measuring chamber being provided with a pair of electrodes for measuring the conductivity of the milk flow.
• Such a mastitis detector is advantageous in that it can be mounted on a milk hose extending from each cow's teat to the milk collecting centre. As a result the milk can be checked each time the cow is milked.
• the flow detector is suited for mounting in the short milk hose extending between the milk collecting centre and the teat cups. The mounting of a mastitis detector of the flow type in each of the short milk hoses renders it possible to detect very early signs of mastitis, and in addition it is possible to determine the location of origin of the disease in the udder.
• Measurements of the conductivity render it possible to determine whether said conductivity is considerably increased at a specific time.
• the electric conductivity is for instance measured by means of electrodes, cf. the description of Dutch Patent Application No. 8301231.
• SE 508458 discloses a device for measuring the electric conductivity of milk.
• the milk from each cow's teat flows through a separate chamber in which two electrodes are arranged for measuring the conductivity.
• the measuring value is transmitted to a particular evaluation unit. No specific type of signal processing has, however, been described.
• GB 2256278 describes an apparatus for detecting the conductivity of milk. The measured conductivity is compared with a pre-set reference value.
• This known apparatus is encumbered with the draw-back that it is necessary to subject the measuring results to a considerable signal processing, and in addition this known apparatus is not particularly flexible.
• the object of the invention is to provide a method of detecting mastitis, and which is far more simple than hitherto known.
• a method of the above type is according to the invention characterised in that the conductivity of the milk from one cow's teat is compared with the conductivity of milk from one or more of the remaining cow's teats, and that an alarm is optionally activated in case the difference exceeds a predetermined value.
• the invention relates also to an apparatus of the type indicated in the preamble of claim 5, said apparatus being characterised by the subject matter indicated in the characterising clause of the claim.
• Fig . 1 is an outline sectional view of a conventionally known milking unit connected to the udder of a cow, a mastitis detector according to the invention being associated with said milking unit and being connected to a measuring unit mounted in the milking centre by means of an electric wire,
• Fig. 2 illustrates a measuring chamber with inlet and outlet openings for the passage of milk from a cow's teat, said measuring chamber being provided with electrodes for measuring the conductivity of the passing milk,
• Fig. 3 is a sectional view of the measuring chamber of Fig. 2,
• Fig. 4 illustrates how the milk is directed from the four cow's teats to their respective measuring chambers
• Fig. 5 illustrates an example of associated values of the conductivity measured in each measuring chamber
• Fig. 6 illustrates a signal graph showing how the measuring signals are handled
• Fig. 7a-7d show a flow chart of a program for processing the measuring signals.
• Fig. 1 illustrates a milking unit 20 connected to the udder 21 of a cow.
• Fig. 1 is a sectional view showing all the four teat cups 22 connected to their respective inlets 25 of the milking centre 24 through the respective four short milk hoses 23.
• the four inlets 25 are uniformly arranged at a distance of 90° from the top side of the milking centre.
• the milk is collected in an outlet 26 from the bottom of the milking centre and subse- quently transferred to a collecting container not shown through a hose 27.
• Fig. 1 shows also the pulsator tubes 28 extending from the pulsator not shown to the individual teat cups 22, as well as a suspension 29 for the milking unit 20.
• Fig. 1 shows a mastitis detector 30 according to the invention.
• This mastitis detector is connected to a measuring unit 32 through an electric cable 31 with seven conductors in the present embodiment, said measuring unit 32 being mounted in the milking centre 24.
• the measuring unit 32 comprises four measuring chambers, viz. one chamber below each inlet 25 in such a manner that during the milking these measuring chambers are filled with milk from their respective cow's teat passing said measuring chambers, but only a representative portion thereof. The remaining milk bypasses the measuring chambers and goes directly into the bowl at the bottom of the milking centre, cf. the more detailed explanation below.
• the measuring chamber 1 , 1 ' is provided with a pair of electrodes 5, 6 for measuring the conductivity of the passing milk.
• a too high conductivity indicates an infection in the teat in question or in the associated milk-producing gland in the udder of the cow. It is, of course, desired to detect such an infected state as early as possible.
• the latter has according to the invention been solved by means of a particular milk collecting housing or milking centre 24, cf. Fig. 1 , in which four separate measuring chambers 1 , 1 ' are provided, viz.
• each chamber 1 , 1 ' is provided with two electrodes 5, 6.
• a temperature measuring device can be inserted, optionally in connection with one of the electrodes 5, 6. The principle is that the conductivity of the milk from each of the teats HB, VB, HF, VF is measured. An increase, if any, of the conductivity of the milk from one of the teats HB, VB, HF, VF is caused by salts, such as NaCl, being hberated, and a relative deviation from the conductivity of the milk from one cow's teat is an early sign of an infection.
• the milk collecting housing 24 in Fig. 1 is connected to a junction cable 31 described in connection with Fig. 1 and being provided with seven conductors, a common earth wire, a conductor for each chamber and two conductors for carrying out a measuring of the temperature.
• the junction cable 31 is as mentioned in connection with Fig. 1 connected to the measuring unit 32.
• the measuring signals in question were transmitted to a so-called management system including historical data on each cow. Furthermore, these data were comparable with the remaining activity of the cow. A high activity, viz. the cow is moving much around, is a sign of the cow being in heat. These activities are detected by means of small electromagnetic markers or radio transmitters secured to each cow.
• the measuring device 30 is a mini version of the above management system. However, it is only adapted to indicate a possible infected stated in one of the teats HB, VB, HF, VF or in the associated gland, cf. Fig. 4 showing the parts in question of the udder.
• the particular advantage of the mini version is that it is portable and able to indicate very early signs of an infected state. Ordinarily, an infection is not discovered until it is obvious due to an visibly changed milk, which occurs 1 to 3 days and nights after the conductivity has been increased.
• the portable measuring device 30 can indicate the te ⁇ nination of the milking.
• a state is also reflected by way of changes in the conductivity and the milk producing capacity.
• the measurements are indicated in form of flashes on the device, the frequency of said flashes representing a measurement of the relative increase of the conductivity.
• a relative increase of the conductivity by 15 % results in a predetermined flashing frequency, an increase of the conductivity by 25 % a higher flashing frequency and a relative increase of the conductivity by 40% an even higher flashing frequency on a light indicator corresponding to the teat in question.
• the observed values are always the highest conductivity values, and in order to ensure that said values are obtained, the measuring is performed a predetermined number of times before the maximum value is measured.
• the measuring of the conductivity is carried out by means of a 50 kHz signal transmitted through a screened cable.
• a Kalman-filter can optionally be inserted, said filter serving to provide the continuous average.
• measuring chambers 1 , 1 ' are provided for measuring the conductivity of passing milk from each of the four cow's teats HB, VB, HF, VF.
• Each new measuring of the conductivity is compared with a variable (reference).
• a variable reference
• a new, mea- sured conductivity presents a higher value than the above variable, viz. the maximum value
• another new variable viz. a maximum value
• VF max : (1-x) • VF max + X • VF where 0 ⁇ x ⁇ 1
• a reference is made to a Table containing the above reference values resulting from a measuring on the system by means of reference fluids presenting different conductivities. Then calculations are made on the resulting data.
• a conductivity value for instance 50 (arbitrary units) has been measured, it is desired to know the conductivity values to be applied to the remaining cow's teats in order to activate an alarm.
• Three alarm levels apply.
• the first alarm level can optionally be 60, i.e.
• Fig. 1 shows the mastitis detector where the lamps for each cow's teat are designated HB, VB, HF and VF like the respective measuring chambers in Fig. 4.
• the temperature indicator is designated T, a status contact S and a switch on con- stant K.
• Fig. 7b showing the checking whether HF max > AD min. If not all the comparisons with HF max are left out and the next program section is started , cf. Fig. 7c showing the checking whether VB max > AD min. If not all the comparisons with VB max are left out and the next and final program section is started, cf. Fig. 7d showing the checking whether HB max > AD min. If not, all the compari- sons with HB max are left out. In other words, the comparisons with conductivity values are only carried out if it makes sense. The advantage of the latter is that the equipment can also be used in the situation where the cow is dry on one or two teats.
• a continuous average is calculated in order to take into account possible erroneous values in such a manner that a possible erroneous value does not form a significant part of the calculation.
• the program does not include a temperature measurement because such a temperature measurement only serves to indicate whether the cow is feverish. Such a measurement is not used for correction. It is only a question of Table references and comparisons with said references.
• the program is controlled by a microprocessor.
• the Table values are encoded in an associated ROM.
• a small RAM is associated. As nothing but comparisons and Table references are to be made, i.e. no actual calculations, it is not required to use a particularly powerful computer.
• Fig. 6 shows a signal graph illustrating how the measuring signals are handled.
• the four measuring signals are fed together with a temperature measurement to a measuring circuit 7 (gate circuit), which determines whether or not the signals are to be transferred to a data processing unit 8.
• This data processing unit 8 is furthermore supplied with the reference values from Table 1 , 2 and 3.
• the data processing unit 8 transmits a signal to the milking control 9 in order to check whether a milking is running. In the affirmative a signal is transmitted to a measuring control 11 so as to open the gate circuit 7.
• a signal is transmitted to the alarm unit 10 which is to check when data are to be erased and another alarm cycle, viz. from cow to cow, is to be started, the old data being erased and a new cycle being started.

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

Family

ID=8102784

Family Applications (1)

Country Status (5)

Cited By (4)

Citations (8)

• 1998
  • 1998-10-05 DK DK199801255A patent/DK174163B1/da not_active IP Right Cessation
• 1999
  • 1999-10-01 EP EP99945964A patent/EP1119236A1/en not_active Ceased
  • 1999-10-01 WO PCT/DK1999/000518 patent/WO2000019807A1/en not_active Application Discontinuation
  • 1999-10-01 AU AU58507/99A patent/AU5850799A/en not_active Abandoned
  • 1999-10-04 AR ARP990105023A patent/AR020708A1/es unknown

Patent Citations (9)

Non-Patent Citations (2)

Also Published As

Similar Documents

Legal Events