The paper presents the results of a study on the formation of colostral immunity and the determination of its duration during the first months of life of calves according to the indications of the level of total IgG and antigen-specific antibodies to pathogens of рarainfluenza 3, respiratory syncytial infection and viral diarrhea of cattle. It has been established that blood serum of newborn calves does not contain antigen-specific immunoglobulins of class G to pathogens of viral diarrhea, respiratory syncytial infection and parainfluenza-3, and the level of total IgG is 2.2 ± 0.61 g/dm3. The concentration of total IgG is increased to 50.50 ± 6.33 g/dm3, and decreases to 27.25 ± 5.82 g/dm3 for 28 days, which contributes to the formation of the immunosuppressive state at the 7th day of a calf life. Starting from 35th day, there is an increase in the concentration of total IgG due to seroconverting of its own antibodies by the body of calves. Immunization of cows-mothers against viral diarrhea, respiratory syncytial infection and parainfluenza-3 contributes to the formation of antigen-specific colostral immunity in calves in the first days of life, which is preserved in diagnostic titers during 63 days after birth.
The increase in the duration of productive longevity of highly productive cows remains a problematic issue and in recent years has attracted increasing attention of domestic and foreign scientists. Accelerated herd turnover and significant premature retirement of Holstein animals in herds may subsequently have negative economic and biological consequences. The analysis of the lifetime productivity of the Holstein cattle of European breeding and their daughters under the conditions of industrial milk production technology has been carried out; the reasons for the culling of animals due to diseases have been clarified. It is established that under the conditions of an industrial complex the period of productive use of Holstein cattle is sharply reduced. The duration of the lactation period in cows-daughters compared with mothers significantly decreased by 463.6 days (by 32.5%) and amounted to only 2.5 lactations (P < 0.01). At the same time, lifelong milk yield was lower by 8427.1 kg (25.9%), and during life from them was received on one calf less. The main reasons for premature departure from the herd of imported animals were: a violation of reproductive capacity (25.6%) and postpartum complications (7.4%), diseases of the digestive system (22.3%), limbs (21.5%) and mastitis (6.6%). Excessive exploitation of animals led to a decrease in natural resistance, which manifested itself in an increase in the number of pathologies of reproductive organs (6.7%), digestive organs (5.5%) and mammary glands (8.5%) among the first-generation cows. Accelerated herd turnover as a result of premature retirement of highly productive cows, necessitates the search for rational ways to increase the natural resistance of the animal organism in conditions of industrial milk production technology aimed at prolonging their productive longevity.
The lifetime productivity of European Holstein cows and their offspring under conditions of industrial milk production technology was studied. It is established that the productive longevity of European Holstein cow offspring in the conditions of the industrial complex was reduced by 1.0 lactation (td = 5.6 or P≥ 0.999), an average of 2.6 lactations. The lifetime milk yield was lower by 20.9% (td = 2.6 or P≥0.99), and the yield of milk fat and protein by 23.0 (td = 3.3 or P≥ 0.999) and 24.1% (Td = 4.8 or P≥ 0.999). At the same time, the influence of origin on lifelong milk yield was 9.5% (P≥0.95), on fat content -22.7% (P≥0.999) and on milk protein -37.5% (P≥0.999). The variation coefficient (Cv = 12.1 ... 79.2%) of animal signs has a sufficient level for carrying out effective breeding work. Revealed high phenotypic and genotypic correlation coefficients between the indices of lifetime productivity (r = + 0.92 ... + 0.98) showed that the breeding of any signs will have a positive effect on others ones. The coefficients of productive qualities heredity (h2 = 0.18 ... 0.23), prove that breeding based on the lifetime productivity signs will have a positive effect on the progress in dairy cattle breeding. Evaluation of dairy cattle productive longevity has great scientific and practical importance. Studies were carried out on Holstein cows using the data of the dairy cattle management system "Orsek". Biometric processing was carried out with the help of Stat Soft software "Statistica 7.0". The advantage of the study lies in the fact that the Holstein of different origins were kept in the same environmental conditions. Intra-breed differences in lifelong productivity of imported cows were revealed. The lifetime milk yield of Danish animals exceeded the average by 1336 kg, fat by 73.4 and protein by 60.7 kg. However, the offspring of imported Hungarian cows were the most suitable for industrial technology. They surpassed the Danish and German opponents by 0.4 and 0.5 lactation in productive longevity, by 9213 and 9688 kg in lifetime milk yield, by 106 and 239 kg in fat and by 72 and 202 kg in milk protein. In general, in conditions of industrial milk production technology, the duration of first-generation cow productive life was reduced by 1.0 lactation (td = 5.6 or P≥ 0.999), in average it was 2.6 lactations. At the same time, the lifetime milk yield of imported animal offspring was significantly lower by 7167 kg, that is, by 20.9% -decreased from 34245 to 27078 kg (td = 2.6 or P≥0.99). As a consequence, the first generation cows' milk fat and protein were lower by 23.0 (td = 3.3 or P≥ 0.999) and 24.1% (td = 4.8 or P≥0.999). It was found that the variability of the signs (Cv) ranged from 14.7 ... 15.4 (protein content) to 42.0 ... 52.6% (milk yield), increasing in the first generation from 11.4 ... 16, 8 to 53.6 ... 56.1%, which indicates the possibility of carrying out effective breeding. Female offspring of imported cows have a low heritability in lifetime milk yield (h2 = 0.02 ... 0.18), in milk fat yield (h2 = 0...
The results of the determination of the efficiency of the cleaning and disinfection protocol of pig farms contaminated by the porcine epidemic diarrhea virus are presented in this study. The research was conducted in the Scientific Research Center of Biosafety and Environmental Control AIC of the Dnipro State Agrarian and Economic University. The experimental part was carried out on the basis of a permanently infected pig breeding farm of the southern region of Ukraine. In order to determine the critical points, a selection of samples of washings/scraps from the surfaces of the pig farm’s premises and the objects of the environment was carried out before cleaning and disinfection and after 1 and 2 premises’ sanitation. A total of 204 tests were analyzed. Disinfection of the territory of pig farms and livestock premises was carried out in accordance with generally accepted methods. Before disinfection, a thorough mechanical cleaning of livestock premises was carried out, with subsequent irrigation of all surfaces with cold tap water. Disinfection of premises and the territory of the pig complex was carried out by the wet cleaning of surfaces with a solution of disinfectant based on glutaraldehyde after preparatory operations in the absence of animals. After disinfection the premises were additionally processed with Ca(OH)2 solution. Washes were obtained with a sterile swab from a surface of 10.0 cm2 by inserting a swab into a test tube with a sterile physiological solution. Scraps from the surfaces were obtained with a disposable sterile blades from the scalpel. The obtained material was placed in disposable sterile plastic 1.5–2.0 cm3 test tubes. The study of the presence of the PEDV was performed using a real-time polymerase chain reaction with the previous reverse transcription of RNA. It was established that the causative agent of PED in a permanently infected farm contaminates most of the production and auxiliary premises and objects of the environment. The one-time cleaning and disinfection protocol does not allow free the farm from the PEDV completely. Only two-time sanitation of premises and objects of the environment with the laboratory control of the efficiency of cleaning and disinfection contributes to the effective eradication of the PEDV.
The current question of today is the formation of effective immune protection in young pigs against infectious diseases, achieved by piglets vaccination in the first weeks of their life. It is known that one of the factors influencing the quality of vaccination is colostral antibodies, which are able to deactivate the vaccine antigen. Considering this, it is important to determine the duration of colostral immunity of piglets to antigens of the Aujeszky’s disease virus during active sows immunization. For this, was formed a group of sows of 2nd-3rd gestation periods with 25 animals in each. Sows were immunized parenterally against Aujeszky’s disease with the «Adivak» vaccine at a dose of 2 ml, by mass vaccination, three times per year. The level of specific antibodies to glycoproteins E (gE) and B (gB) was determined in the blood serum of piglets before sucking colostrum and every 7 days of life until 77 days from birth by enzyme-linked immunosorbent assay (ELISA). It was revealed that before consuming colostrum, piglets did not have specific antibodies to the antigens of the Aujeszky disease virus. From 7th till 70th days of life, all piglets had specific IgG to the antigens gB and gE of the Aujeszky disease virus, and by the seventy-seventh day, 29% of the animals were seronegative. Thus, newborn piglets before colostrum suckling do not have specific immune protection against the Aujeszky disease virus against the background of sow immunization. Consumption of colostrum by piglets promotes their formation of colostral immunity, specific to the antigens of the Aujeszky disease virus. The duration of colostral antibodies’ circulation specific to the antigens of the Aujeszky disease virus in the piglets peripheral blood is 70 days. On the seventy-seventh day from birth, the level of colostral immunoglobulins decreased sharply, which contributed to the appearance of seronegative animals and an increase in their sensitivity to the action of an epizootic strain of the virus.
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