RU2311759C2 - Method and device for predicting subclinical mastitis in cows - Google Patents

Abstract

FIELD: veterinary science.

SUBSTANCE: the present innovation deals with detecting the average value of milk electroconductivity by stock and electroconductivity of the sample under testing. It is necessary to fill the tank with milk, put there a sensor's edge, mix for 10 sec and compare the difference between standard and tested samples, at obtaining the difference being equal to 10% it is possible to diagnose subclinical mastitis. The device suggested has got a power pack, a measuring block supplied with an indicator and a sensor with active and passive electrodes, passive electrode is designed as a hollow cylinder with inner coaxially located active electrode as a metal rod, the space between electrodes is filled with sealing agent. The innovation in question enables to shorten the time for measurements.

EFFECT: higher efficiency and accuracy of diagnostics.

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Description

The invention relates to veterinary medicine, and in particular to methods for diagnosing subclinical mastitis in cows.

A known method and device for determining the subclinical form of mastitis of cows "SOMATOS", including mixing milk with the drug mastoprim, and then measuring the viscosity of the mixture and determining the number of somatic cells according to the data obtained (see Solopov A.A. Express analyzers for monitoring the quality of milk. / / Practice. - St. Petersburg: Beresta, No. 9-10, 2004, S.13-15).

The disadvantage of this method for the diagnosis of mastitis is the need to use an additional diagnostic drug, low diagnostic rate. The disadvantage of this device is the large weight (5 kg), large dimensions.

The closest in technical essence to the claimed and selected as a prototype is a device and method for diagnosing mastitis, including mixing milk with a mastidine preparation, then determining the conductivity of the mixture with a device, comparing the data with the reference data (see RF patent No. 2210768, class G01N 33/48 from 2003).

The disadvantages of this device and method are the need to use an additional diagnostic drug, the complexity of the diagnosis associated with constant monitoring of non-mastitis milk for each sample.

An object of the invention is to change the design of the measuring sensor and circuitry of the device for determining subclinical mastitis in cows, simplifying the method.

The problem is achieved in that in a method for diagnosing subclinical mastitis in cows, including determining the electrical conductivity in a milk sample from a group of cows and comparing the obtained indicator with a reference, according to the invention, subclinical mastitis is diagnosed when a difference of 10% between the reference and test samples is obtained.

The problem is achieved in that the device for the diagnosis of subclinical mastitis in cows, consisting of a power supply, a measuring unit with an indicator and a sensor, according to the invention, is additionally equipped with active and passive electrodes, the passive electrode being made in the form of a hollow cylinder, inside of which there is an active coaxial an electrode made in the form of a solid metal rod, and the space between the electrodes is filled with an insulating sealant.

The invention also consists in the fact that to control the purity of the electrode system, the active electrode is equipped with an additional switch and exemplary resistance

The invention is illustrated by drawings.

Figure 1 shows the structural diagram of the device, figure 2 is the same sensor, section.

The device contains a harmonic oscillation generator - 1, an exemplary resistance - 2 for controlling the purity of the electrode system in the form of a key, a measuring sensor - 3, a rectifier - 4, an analog-to-digital converter - 5, a digital liquid crystal indicator - 6. The circuit for generating the reference voltage, power on, power off and backlight on / off switches are not shown in the block diagram. The listed elements are interconnected as follows: the output of the harmonic oscillator through normally closed contacts is connected with the key-input to the input of the measuring sensor 3, through the normally open contacts of the key key with exemplary resistance 2, the output of the rectifier 4 is connected to the input of the analog-to-digital converter 5, the output of which connected to a digital liquid crystal display 6.

The sensor is a brass electrodes with a Nickel coating - 7, between which the space is filled with an insulating polymer composite - 8 (figure 2).

The device operates as follows.

After applying the voltage, the harmonic oscillation generator 1 starts, at the output of which an alternating voltage of a sinusoidal shape is formed, stable in frequency and amplitude. From the output of the generator, an alternating sinusoidal voltage is supplied simultaneously to the measuring sensor 3 and the normally open contacts of the key of the key. In preparation for operation, to check the purity of the measuring sensor 4, close the key, the voltage drop on the parallel-connected (when the key is closed) the model resistance 2 and the measuring sensor 3 will carry information about the cleanliness of the electrode system of the measuring sensor. In the measurement mode, the key-key is in the open state, the measuring sensor 3 is placed in the test milk, the interelectrode voltage drop carries information about the total resistance of the test milk. The voltage drop proportional to the total resistance of the milk from the output of the sensor 3 is fed to the input of the rectifier 4, where it is converted to a constant voltage supplied to the information input of the analog-to-digital converter 5. In the analog-to-digital converter, the input DC voltage is converted to a seven-segment digital code with subsequent display digital value of the total electrical resistance of milk (Ohms) on a digital liquid crystal display 6.

The method is as follows.

After turning on the power of the device, rinse the electrode system of the sensor in boiled cold water.

Filling the container with milk to approximately one level of 80-90% of the volume, the end face of the sensor is placed in the center of the lower half of the volume of milk poured, do not touch the bottom of the container, the walls of the container, the foam layer with the electrode system. After weak mixing, the measurement time should not exceed 10 seconds, during which the measurement result is read from a digital indicator. After each measurement, it is necessary to rinse in water and wipe the end of the measuring sensor with a cotton swab with alcohol.

To determine the average value of the herd, it is necessary to measure the indicator of milk samples from a group of clinically healthy cows and determine the arithmetic average value. The obtained value will be the norm of electrical resistance of milk for a given farm for this period of time.

If the obtained value is below the norm by 10% or more, then for this cow it is necessary to check each lobe of the udder with a mastitis device (the device’s action is based on the conductometric method for detecting abnormal milk).

The invention is illustrated by the following example.

The diagnostic efficiency of the apparatus was evaluated in comparison with the widely used diagnostic method for the subclinical form of mastitis with mastidine 10% (Volga Biological Factory TU 10.19.25-88).

To conduct diagnostic efficacy, 20 heads of black-motley cattle with signs of a subclinical form of mastitis were taken, which were determined by the above-described device technique. The results of the study of milk meet the quality requirements in accordance with GOST 52054-2003 from 01.01.2004.

According to GOST 52054-2003, premium milk must contain somatic cells no more than 300 thousand / ml, 1 grade no more than 500 thousand / ml; microbial contamination should be no more than 500 CFU / ml for milk of the highest grade, and no more than 1000 CFU / ml for 1 grade.

Diagnostic effectiveness of detecting cows in the stage of subclinical mastitis No. Animal number The indicator of electrical resistance of milk, Ohm The average resistance of milk to the herd, Ohm Test with mastidine The number of somatic cells, thousand / ml Microbial contamination, m CFU / ml one 6577 167 202 Put it. 1650 1300 2 4571 177 Doubts. 1600 1220 3 4022 153 Put 1750 1023 four 2877 166 Put 1745 1010 5 7132 151 Put 1830 1460 6 7634 163 Put 1740 1090 7 3211 159 Put 1890 1240 8 3455 160 Put 1735 1100 9 7815 174 Denied. 1538 1090 10 7895 177 Denied. 1530 1050 eleven 7677 173 Doubts. 1545 1090 12 7865 171 Put 1561 1120 13 3477 168 Put 1622 1260 fourteen 5656 163 Put 1643 1350 fifteen 3344 160 Put 1660 1390 16 8137 167 Put 1610 1270 17 3429 161 Put 1631 1280 eighteen 3455 172 Denied. 1556 1100 19 3569 171 Put 1536 1090 twenty 3587 165 Put 1680 1270

In this case, according to the invention, by definition of the subclinical form of mastitis, sick animals are those whose rate is 10% lower or more than the average herd score (202-20.2 (10%) = 181.8).

Diagnostic studies by the claimed method showed that the detection of a subclinical form of mastitis in cows was noted in 20 cases (100%). When diagnosing mastidine breakdown - 16 (80%).

The research results show that the diagnostic efficiency of the proposed device is 20% higher than the mastidine test, in addition, the amount of time spent on one study of the mastidine test was 1.5 ± 0.25 min, while using the device it was 10.0 ± 4.0 sec.

Thus, the proposed method and device can reduce by several times the measurement time, the cost of measurements, increase the reliability of determining patients with mastitis animals, improve the convenience of measurements. The present invention is also industrially applicable, because can be manufactured industrially.

Claims (3)

1. A method for diagnosing subclinical mastitis in cows, including determining the electrical conductivity of average milk in a herd from a group of clinically healthy cows and determining the electrical conductivity of the test milk sample, for which they fill the tank with milk, place the sensor end in the center of the lower half of the milk volume and, after gentle mixing, measurement is 10 s, characterized in that they compare the difference in the electrical conductivity of milk between the reference and the test samples and when receiving a difference of 10% diagnose subclinical mastitis. 2. A device for diagnosing subclinical mastitis, including a power supply, a measuring unit with an indicator and a sensor, characterized in that the measuring sensor is equipped with active and passive electrodes, the passive electrode being made in the form of a hollow cylinder, inside of which an active electrode is coaxially located, made in the form a solid metal rod, and the space between the electrodes is filled with insulating sealant. 3. The device according to claim 2, characterized in that for monitoring the purity of the electrode system, the active electrode is equipped with an additional switch and exemplary resistance.

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