RU2263467C1 - Method for detecting pulmonary insufficiency in calves - Google Patents

Abstract

FIELD: veterinary science.

SUBSTANCE: as functional loading one should apply respiratory cessation for 30 sec to detect the index of pulmonary insufficiency (IPI) by the following formula: IPI=R₂/R₁, where R₁ - the quantity of respiratory movements per min at rest time; R₂ - the quantity of respiratory movements per min after 30-sec-long cessation of respiration, and at IPI value 1.5 one should diagnose the pathology in respiratory organs. The present innovation enables to detect latent pulmonary insufficiency in calves in shorter terms.

EFFECT: higher efficiency of detection.

3 ex, 1 tbl

Description

The invention relates to the field of veterinary medicine, relates to a method for detecting pulmonary failure in calves.

Pulmonary insufficiency - the inability of breathing to ensure normal oxygen saturation of the blood and at the same time remove carbon dioxide. The main clinical syndrome of respiratory pathology is pulmonary failure, which is accompanied by weakness, cyanosis of the mucous membranes, shortness of breath. Depending on the severity of shortness of breath, pulmonary failure is divided into three degrees: 1 (latent) - shortness of breath occurs only with intense physical exertion; 2 - shortness of breath occurs with little physical exertion; 3 - shortness of breath is observed constantly both at rest and under load / 1, 2 /.

With pulmonary insufficiency of the first and second degrees, compensation for gas exchange and oxygen deficiency in the blood is not possible. With pulmonary insufficiency of the third degree, hypoxia and / or hypercapnia occurs, which can cause a coma and result in death.

A known method for detecting pulmonary failure in animals, which consists in the use of dosed physical activity for 15 minutes. In animals, the frequency of respiratory movements at rest is determined immediately after an easy 15-minute run, and then periodically until the respiratory rhythm is restored to its original values. After the run, the number of respiratory movements in healthy animals is restored after 7-10 minutes. In case of insufficiency of external and internal respiration, the number of respiratory movements after the run is restored in 20-30 minutes or more / 3 /.

However, this method is very laborious (not carried out directly at the location of the calves in the machine, on a leash), in addition, when using this method, the time for detecting pulmonary insufficiency is lengthened.

The technical result of the invention is the acceleration of the detection of pulmonary failure in calves and the reduction of its complexity.

The technical result is achieved by the use of artificial respiratory arrest (APNE) for 30 seconds and the detection of an index of pulmonary failure. Experimental studies found that a 30-second artificial respiratory arrest in clinically healthy calves leads to an increase in the partial pressure of carbon dioxide - pCO ₂ from 44.6 to 49 mm RT. Art. (9.9%) and a decrease in the partial pressure of oxygen pO ₂ from 38.6 to 33.5 mm RT. Art. (13.2%). In calves that are in the recovery phase as in remission, with bronchopneumonia, the partial pressure of carbon dioxide increased from 54.4 to 67.1 mm Hg. Art. (24.3%), and the partial pressure of oxygen decreased from 48.7 to 29.5 mm Hg. Art. (39.4%). That is, in calves with pathology of the respiratory system more carbon dioxide accumulates and a greater oxygen deficiency occurs, which affects the number of respiratory movements and restoration of breathing. So, in calves with a pathology of the respiratory system, after a 30-second breath hold, the number of respiratory movements increased from 26 to 42 (by 61%), and in healthy - from 26 to 32 (by 23%) respiratory movements.

The method is as follows.

In calves in a calm state, the number of respiratory movements per minute is determined. Then, while exhaling, stop breathing, closing the nostrils for 30 seconds. Then the number of respiratory movements is calculated. The ratio of the number of respiratory movements after the cessation of breathing to the number of them at rest determines the index of pulmonary insufficiency. That is, the index of pulmonary insufficiency (ILI) is calculated by the following formula:

where D ₁ - the number of respiratory movements at rest;

D ₂ - the number of respiratory movements after a 30-second breath hold.

With an index of pulmonary failure> 1.5, a pathology of the respiratory system is diagnosed.

The invention can be used to detect hidden pulmonary insufficiency in calves both in large livestock complexes and in small farms, which is very important when selecting calves for rearing, buying and selling animals, and monitoring the effectiveness of treatment of calves with respiratory pathology.

The detection of pulmonary insufficiency using the proposed method was carried out in 3 farms of the Voronezh region - AOZT “Paris Commune” of the Verkhnekhavsky district, STOO “Zarechye” of the Rossoshansky district and at the experimental station of the Voronezh State Agrarian University (Voronezh) at 172 calves 1-3, 5 months of age.

Using the proposed method in practice showed its main advantages:

1. Conducting directly at the location of the animal;

2. Reduction of more than 10 times the time of detection of latent pulmonary insufficiency.

The essence of the method is illustrated by examples.

Example 1

The rationale for the relationship of the index of pulmonary failure with the acid-base state and the gas composition of the blood of healthy calves with pathology of the respiratory system.

In a long-term respiratory illness farm, 8 calves of 1.5 - 2 months of age were selected, 4 of them were patients with bronchopneumonia in the recovery phase and 4 clinically healthy. Blood was taken from calves to determine indicators of the acid-base state and to determine the index of pulmonary insufficiency. The results of the studies are presented in the table.

Table. Indicators of the acid-base state and gas composition of blood in healthy and sick calves with bronchopneumonia No animal Index
pulmonary insufficiency, units PH, units PCO ₂ , mmHg Standard Bicarbonates (SB), mM / L Excess base (BE), mM / L H ₂ CO ₄ , mg / L The ratio SB / H ₂ CO ₄ Buffer bases (BB), mM / l PO ₂ , mmHg Diagnosis 1 2.1 7.44 54,2 27.8 +4.2 1,60 1:17 46.8 42.5 is ill 2 1,6 7.43 48.7 33.5 +10 1,60 1:21 53.0 54,4 is ill 3 2.0 7.38 52,4 26.6 +4 1,57 17: 1 46.5 26.1 is ill 4 1.7 7.35 54.7 25.7 +3.1 1.65 16: 1 45.1 24.7 is ill 5 1,1 7.36 36.7 23.6 -0.5 1.22 19: 1 39.5 40.6 is healthy 6 1,2 7.35 38.6 23,2 -1.0 1.34 17: 1 40.3 44.6 is healthy 7 1.4 7.33 33.0 23.7 -0.3 1.48 16: 1 40,0 49.3 is healthy 8 1,5 7.36 40,0 24.4 -10 1.20 1:20 43.7 33 is healthy

The table shows that in calves suffering from bronchopneumonia, in the stage of recovery, the acid-base state (No. 1-No. 3) was characterized as decompensated metabolic alkalosis, as evidenced by high blood pH, excess bases (metabolic component of the acid-base state of the blood) and increased partial pressure of carbon dioxide (the gas component of the acid-base state of the blood). In calf No. 4, the acid-base state was characterized as a compensated metabolic alkalosis — normal blood pH, excess of bases, and increased partial pressure of carbon dioxide. Due to the violation of the acid-base state and the high content of carbon dioxide in these animals, the index of pulmonary failure ranged from 1.6 to 2.1 units.

In clinically healthy calves, the acid-base state was characterized as compensated respiratory alkalosis, as evidenced by normal blood pH, excess of bases, normal partial pressure of carbon dioxide. Due to the normal acid-base state of the blood and the normal partial pressure of carbon dioxide in these animals, the index of pulmonary failure did not exceed 1.5 units.

Example 2

Justification of the relationship of the index of pulmonary failure with morphological changes in the respiratory system.

In the farm STTO "Zarechye" 28 calves were determined by ILI according to the claimed method. Of these, 8 calves ILN exceeded 1.5 units. In the same animals (with pathology of the respiratory system), morphological studies of the respiratory system were performed. As a result, it was found that the earliest structural changes are found in the mucous membrane of the upper respiratory tract, which is manifested by an increase in the number of goblet cells and their hypersecretion, and mucosal degeneration of the epithelium of the terminal sections of the tubular-alveolar serous glands of the submucosal layer of the nasal septum. Alternative processes with desquamation of the epithelium of the mucous membrane and serous glands in the nasal cavity and trachea were observed. The mucous membrane was edematous, swollen, its surface was tuberous with an increase in the number of hypertrophied goblet cells. Moreover, the relative proportion of pure alveoli is significantly reduced, sometimes more than 2 times. Changes in the surfactant complex were electron microscopically manifested by the destructive processes of the system of lamellar bodies of type 2 alveolocytes and the destruction of the surfactant lining on the surface of the pulmonary alveoli.

Macroscopic changes in the lungs of calves were characterized by the presence in the bronchi of foamy-mucous exudate, hyperemia of the mucous membrane of the bronchi. During incision and alveolar tissue, a gray-brown exudate of mucus-like consistency was extruded. The lungs in the total mass were enlarged, had a color from light pink to reddish cherry and dense texture.

Thus, morphological studies showed the presence of respiratory pathology in these 3 calves, which confirmed the relationship between respiratory pathology and IDN. With pathology of the respiratory system, the flow of air into the lungs decreases, which leads to a deterioration of gas exchange in them in these animals and an excess of pulmonary insufficiency index of 1.5 units.

Example 3

Justification of effectiveness.

In the farm for the selection of calves for rearing, a group of calves of 1.5-2.5 months of age was formed. To detect pulmonary failure, two methods were used: the claimed one and the known one. For this purpose, all animals were subjected to functional load - a 15-minute run. In calves, the number of respiratory movements at rest was determined, and after loading, the time of restoration of respiratory movements to the initial values was determined. As a result, it was found that in 17 calves the number of respiratory movements returned to their original state in more than 10 minutes.

In the same 17 calves, when detecting pulmonary insufficiency by the claimed method, after 4 hours, the index of pulmonary insufficiency exceeded 1.5 units.

As a result, pulmonary failure was detected by both methods to the same extent. At the same time, the use of the proposed method has significantly reduced the time to detect pulmonary failure and minimize the complexity of the process.

Sources of information

1. Zilber A.P. Respiratory failure [Guide for doctors] - M .: Medicine, 1989, 512 p.

2. Clinical diagnosis workshop with radiology / Belyakov IM, Dugin GL and etc./. - M.: Kolos, 1992 .-- 286 p.

3. Clinical diagnosis of internal non-communicable diseases of farm animals. - V.I. Zaitsev et al. - 3rd edition, revised. and add. - M., 1971 - p. 135-136.

Claims (1)

A method for detecting pulmonary insufficiency in calves, including the use of a functional load on the body, characterized in that respiratory arrest for 30 s is used as a functional load, after which the pulmonary insufficiency index (PPI) is determined by the following formula:

, where D ₁ - the number of respiratory movements per minute at rest; D ₂ - the number of respiratory movements per minute after a 30-second breath hold; with a value of ILI> 1.5, a pathology of the respiratory system is diagnosed.