RU2802503C1 - Method of predicting late toxicosis in pregnant cows - Google Patents

Abstract

FIELD: veterinary medicine; veterinary obstetrics.

SUBSTANCE: invention relates can be used to predict late toxicosis (preeclampsia) in pregnant cows. The method includes determining the thrombin time in blood plasma on days 60–65 or 135–150 of pregnancy. If its value is less than 87.3 seconds, late toxicosis of pregnant women is predicted.

EFFECT: invention provides prediction of late toxicosis in pregnant cows, which allows to timely start the treatment to normalize metabolic processes in the body of pregnant animals, aimed at obtaining a viable offspring.

1 cl, 2 tbl, 2 ex

Description

The invention relates to the field of veterinary medicine, in particular to veterinary obstetrics, and can be used to predict late toxicosis (preeclampsia) in pregnant cows.

Late toxicosis of pregnancy (preeclampsia) is a pathological condition of pregnant animals, manifested by the syndrome of multiple organ functional failure.

Clinically, gestosis is diagnosed on average in 12-40% of deep-pregnant cows and heifers in the last 1.5-2 months of pregnancy. The frequency of its manifestation is predetermined by genetic predisposition, the presence of one or another extragenital pathology, the state of animal nutrition and the degree of metabolic disorders. The highest probability of manifestation of this pathology is inherent in highly productive animals, as well as heifers [Nezhdanov A.G., Retsky M.I., Alekhin Yu.N., Safonov V.A. and others. Clinical, hematological and biochemical status of cows with gestosis // Agricultural biology. - 2010. - No. 4. - P. 118-123].

With the development of gestosis, the pathological process involves the kidneys, liver, fetoplacental complex, cardiovascular, pulmonary and central nervous systems. In this case, the intrauterine development of the fetus is disrupted, the birth of a low-viability offspring is noted, and in postpartum women - the development of severe forms of complications of the birth act and the early postpartum period. The frequency of their manifestation in comparison with clinically healthy animals increases by 2.5-3 times [Safonov V.A. Hemomorphological changes in cows during different periods of reproduction // Bulletin of the Russian Academy of Agricultural Sciences. - 2008. - No. 5. - P. 64-67].

Normal pregnancy is accompanied by many changes aimed at ensuring the growth and development of the fetus. During pregnancy, changes also occur in the hemostatic system. Disturbances in the hemostatic system play a significant role in the development of late toxicosis in pregnant women. During the normal course of pregnancy, the activity of the blood coagulation system as a whole increases. The balance between the coagulation and anticoagulation systems is maintained through the interaction of platelets, coagulation factors and the process of fibrinolysis. A disorder affecting any of these links can cause serious pregnancy complications. Among these complications, the most dangerous is disseminated intravascular coagulation (DIC), which develops due to activation of the coagulation system, on the one hand, and the fibrinolysis system, on the other. One of the indicators of the activity of the blood coagulation system is thrombin time, the shortening of which indicates increased formation of a blood clot, the risk of developing vascular thrombosis, decreased blood supply to the fetus and the development of late toxicosis of pregnancy.

There is a known method for predicting gestosis in pregnant women, which consists in determining the concentration of placental alkaline phosphatase and lactoferrin in the daily urine of pregnant women at 20-22 weeks of pregnancy and again after 2 weeks, and based on the sum of the concentrations of placental alkaline phosphatase and lactoferrin concentrations above 16.0 ng/ml, the development of gestosis is predicted . The accuracy of the forecasting method is 75.0% [RU 2553624С1, G01N 33/48, 06/20/2015 Bull. No. P].

The disadvantage of this method of predicting gestosis in pregnant women is its low accuracy, as well as the ability to predict gestosis starting only from 20-22 weeks of pregnancy, when clinical signs begin to appear and the need for therapeutic measures arises.

There is a known method for predicting gestosis, which consists in determining the concentration of antibodies to neurospecific enolase and gliofibrillary acid protein in the blood serum of pregnant women. The development of gestosis is predicted when the level of anti-NSE antibodies is more than 0.6 μg/ml or anti-NSE antibodies is more than 0.9 μg/ml. The specificity of the prediction method is 93.2% [RU 2287823С1, G01N 33/53, G01N 33/68, 11/20/2006 Bull. No. 32].

The disadvantage of this method of predicting gestosis in pregnant women is that it is labor intensive and requires special equipment and diagnostic test systems when conducting laboratory blood tests.

The prior art does not know any method for predicting late toxicosis in pregnant cows. In veterinary medicine, gestosis is diagnosed when it is clinically manifest.

The invention solves the problem of developing a method for predicting late toxicosis in pregnant cows, which would allow timely initiation of treatment to normalize metabolic processes in the body of pregnant animals, aimed at producing a viable offspring, which will reduce the incidence of illness during childbirth and in the postpartum period.

To solve this problem, a method has been proposed for predicting late toxicosis in pregnant cows, including determining the thrombin time in blood plasma on days 60-65 or 135-150 of pregnancy and, if its value is less than 87.3 seconds, predicting late toxicosis in pregnant women.

Thrombin time is the rate of transformation of fibrinogen into fibrin. Thrombin is formed at the end of the blood coagulation cascade, ensures the polymerization of fibrinogen and the formation of a fibrin clot. Due to the general activation of blood coagulation, thrombin time tends to decrease slightly during pregnancy. Determination of thrombin time is used to determine the functional activity of fibrinogen, to monitor heparin therapy and fibrinolytic therapy, to diagnose the activation of fibrinolysis.

The method is carried out as follows.

On days 60-65 or 135-150 of cows' pregnancy, venous blood is collected. Thrombin time is determined in blood plasma using a set of reagents for determining thrombin time. Based on the research results, late toxicosis of pregnant women or the physiological course of gestation is recorded.

The essence of the technical solution is illustrated by examples:

Example 1. Venous blood samples were obtained from 16 highly productive cows of the black-and-white breed on days 60-65 of pregnancy. Thrombin time was determined in blood plasma using a set of reagents for determining thrombin time (Thrombin test) from RENAM MBOOI (Russia). Clinical and laboratory assessment of the course of pregnancy was carried out on days 60-65, 135-150 and 210-230 of gestation using transrectal palpation and ultrasound scanning using an Easy-Scan-5 ultrasound scanner (Ireland) equipped with a linear sensor with a frequency of 7.5 MHz . During the same period of pregnancy, blood pressure in the tail artery, the presence/absence of protein in the urine and edema of the subcutaneous tissue, which characterize the development of late toxicosis of pregnancy, were determined in animals. Based on the results of these studies, late toxicosis of pregnant women or the physiological course of gestation was recorded.

The results obtained are presented in Table 1. From the data in Table 1 it follows that from 16 cows examined during 7 months of pregnancy and blood tests were performed to determine thrombin time on days 60-65 of gestation, the following results were obtained:

True positive result (IP) - 7

False positive result (FP) - 1

True negative result (TN) - 8

False negative result (FN) - 0

The accuracy of the method was: (IP+IO):N×100%=(7+8):16×100=93.8%

The specificity indicator of the method was: AI:(IO+LP)×100%=8:(8+1)×100=88.9%

Example 2. The experiment included 16 cows of the black-and-white breed. Blood for analysis to determine thrombin time was obtained on days 135-150 of pregnancy. To assess the condition of pregnant cows and thrombin time indicators, clinical and laboratory diagnostic methods were used, described during the first experiment.

The data obtained are presented in Table 2. From the data in Table 2 it follows that from 16 cows examined during 7 months of pregnancy and blood tests were performed to determine thrombin time on days 135-150 of gestation, the following results were obtained:

True positive result - 8

False positive result - 0

True negative result - 7

False negative result - 1

When calculated using the above formulas, the accuracy of the method was 93.8%, specificity - 100%.

A comparison of the data from the first and second experiments indicates that the accuracy and specificity of the claimed method in determining the thrombin time in blood plasma on days 135-150 of pregnancy corresponds to the indicators on days 60-65 of pregnancy.

Thus, a close relationship is revealed between the thrombin time in the blood plasma on days 60-65 and 135-150 of pregnancy and the subsequent clinical manifestation of late toxicosis in pregnant women. The accuracy and specificity of the claimed method for predicting late toxicosis in pregnant cows is achieved in the early period of gestation (60-65 and 135-150 days).

Claims (1)

A method for predicting late toxicosis in pregnant cows, including determining the thrombin time in the blood plasma on days 60-65 or 135-150 of pregnancy, if its value is detected to be less than 87.3 seconds - predicting late toxicosis in pregnant women.