The purposes of this study were to describe the clinical signs observed in PRRS positive herds during a porcine reproductive and respiratory syndrome (PRRS) outbreak in Ontario and to determine associations between these clinical signs and herd demographics and PRRS control strategies. All PRRS polymerase chain reaction-(PCR)-positive submissions to a diagnostic laboratory between September 1, 2004 and August 31, 2007 were identified (n = 1864). After meeting eligibility requirements and agreeing to voluntary study participation, producers from 455 of these submissions were surveyed for information on clinical signs observed in their herds, herd demographics, and PRRS control strategies used in their herds at the time that the PCR-positive samples were taken. Larger herd size was associated with an increased risk of reporting abortion, weakborn piglets, off-feed sows, and sow mortality in sow herds, and with an increased risk of reporting mortality in finishing herds. When disease control strategies were examined, use of a commercial PRRS vaccine in sows and gilts was associated with a decreased risk of reporting weakborn pigs and high pre-weaning mortality, while the use of serum inoculation in breeding animals was associated with an increased risk of reporting off-feed sows and sow mortality. Providing biofeedback of stillborn/mummified piglets, placenta or feces to gilts was associated with an increased risk of reporting respiratory disease and mortality in finishing pigs while all-in/all-out flow in farrowing rooms was associated with an increased risk of reporting sow mortality and weakborn piglets.

In the conditions of the Republic of Belarus there were studied biochemical indexes of calf blood serum against the background of application of probiotic preparations Bilavet C. Results of research showed that administration of probiotic preparations from the first day till the six day and from the fourteenth day till the nineteenth day of calf life with the preventive purpose rendered the simulative influence on indexes of natural resistance, which were accompanied with the increasing of total protein quantity in blood on 2,9-5,9%, as well as the increasing of protein fractions, in particular, globulin-rich fraction on 4,2-6,4%. Administration of probiotic preparation Bilavet С to calves rendered the positive influence on blood biochemical indexes, promoted the uptaking and better accumulation of mineral substances: content of crude calcium, inorganic phosphorus, magnesium, iron increased on 15,3%, 10,5%, 13,2% and 3,6%, respectively.

In the conditions of the Republic of Belarus there were studied circadian rhythms of some haemotological and biochemical blood indexes of clinically healthy calves and calves with a respiratory syndrome. There was analyzed the efficiency of administration a new complex mineral preparation CMP for correction of internal desynchronoses in complex therapy of calves with respiratory pathologies. Diseases of calves with a respiratory syndrome were accompanied by infringements of circadian fluctuations rhythm (internal desynchronosis) of haemotological and biochemical blood indexes. Application of an antimicrobial preparation Ampicillin for treatment of respiratory diseases of calves promoted the recovery of calves. Introduction of CМP preparation into therapeutic regimen of calves with respiratory syndrome proved to be rather effective; it promoted the correction of metabolic desynchronoses which accompanied the basic disease. Combined application of CМP and Ampicillin made it possible to speed up the clinical recovery of calves and on 30% to prevent animal mortality.

In the conditions of the Republic of Belarus there was studied a comparative efficacy of methods of drug administration for diseased animals with respiratory diseases. It was stated that enteral (internal) administration of Tromexin in a complex therapy of calves with respiratory pathology possesses rendered low therapeutic efficacy and could have a lethal outcome. Parenteral (intramuscular) administration of Enrotil and Dexafort for a complex therapy of calves with respiratory pathology rendered a moderate therapeutic efficacy and could lead to animal's state improvement. Parenteral (intravenous) administration of hypertonic solutions of norsulfazol, calcium chloride, sodium chloride and glucose in complex therapy of calves diseased with a respiratory pathology proved to render a high therapeutic efficacy and may lead in a complete clinical recovery.

In the conditions of the Republic of Belarus there was analyzed the influence of inclusion into broiler chickens diets of probiotoc preparation Bifidoflorin zhidkij (liquid) and prediotic veterinary drug Biofon AIL on the natural resistance, hematopoiesis, growth, metabolic function, development and viability of broiler chickens. In course of the study there was analyzed the dynamics of total haemoglobin, total protein of blood serum, albumins and globulins of broiler chickens which were fed with veterinary drugs probiotoc Bifidoflorin zhidkij and prediotic Biofon AIL. Indexes of chicken viability and life weight gain were marked. Research results showed that application of the presented veterinary preparations rendered the growth promoting action, lowering of disease incidence, increasing of chicken viability, increasing of live weight gain and stimulation of metabolic processes in the most intense period of poultry growing. All these factors were expressed in highest degree after the combined application of the probiotic and prebiotic veterinary drugs.

In the conditions of the Republic of Belarus annually in 25-50% of total number cattle there was stated ketosis (milk fever); as a result, from each cow in cattle breeding farms receive less milk per lactation on 10-15%, as well as there is a lowering of fat and protein (and biological value) content in milk. In course of the study there was analyzed the influence of mineral and energy supplement Felutsen K-1-2 for the preventive treatment of ketosis of highly productive cows. Research results showed that application of the analyzed additive rendered the positive influence on morphological and biochemical blood indexes. In particular, there was an increasing of hemoglobin level, content of total protein, albumins, magnesium, calcium, and phosphorous. It also rendered positive influence on lipid exchange. In course of the study it was marked, that the prophylactic efficacy of mineral and energy supplement Felutsen K-1-2 in the experimental groups was 100%, and the control one – 80%.

In the conditions of the Republic of Belarus there was studied the influence of herbal infusion, tincture, liquid and dry extracts of elecampane (Inula helenium) on morphological and biochemical indexes of pig blood. In course of the study it was established, that preparative forms of elecampane stimulated the formation of blood corpuscle, and also increased of the hemoglobin level in blood of pigs. Administration of elecampane preparations did not cause any authentic changes in blood leukogram of swine; all indicators were within normal limits. Elecampane preparations did not cause changes on the part of biochemical blood indexes of and did not influence the activity of enzymes. Research results showed that herbal infusion, tincture, liquid and dry extracts of elecampane did not render negative influence on swine.

In the conditions of the Republic of Belarus there was studied the antihelmintic characteristics of the preparative forms of marsh cinquefoil (Comarum palustre): herbal infusion, infusion, liquid, extract, pulvis. The research has shown that these preparative forms in the specified dozes had a rather high therapeutic efficiency against strongylatosis of gastro-intestinal tract of young ruminants. The highest therapeutic effect was rendered by a liquid extract of Comarum palustre after its administration to animals in a dose of 0,2 ml/kg twice with 24 hour interval. In this case during the strongylatoses of a gastroenteric tract the antiparasitic intensefficiency of sheep and cattle by the end of experience was 98,1% and 97,3% respectively, and antiparasitic extensefficiency was 90% for both kinds of animals. After herbal infusion application of Comarum palustre for animals (in a dose of 7 ml/kg of live weight before feeding once a day within 3 days continuously) by the end of the 14 day of the experiment made it possible to obtain intensefficiency of 70% for both animal species, and extensefficiency of 60% for sheep and 70% - at calves. Tincture application of marsh cinquefoil for animals in a dose of 1 ml/kg of live weight of twice with 24 hours interval, provided the intensefficiency of 85% for sheep and 84% - for cattle, and extensefficiency of 70% and 80%, respectively. In the conditions of application of a pulvis of marsh cinquefoil in a dose of 500 mg/kg of live weight twice with 24 hours interval, made it possible to obtain the 63,4% intensefficiency for sheep and 67,8% - for calves, and extensive efficiency - 50% and 40%, respectively.

In the conditions of the Republic of Belarus there was developed and a simple and applicable for industrial production method of immunoglobulin production against animal salmonellosis. The following initial raw materials were used for production of the specific immunoglobulin: blood serum of bulls which were hyperimmunized with formolated antigen on the basis of four serovars: S. typimurium; S. abortusovis; S. dublin; S. choleraesuis. In course of the study there were analyzed chemical and biological indexes of immunoglobulin of experimemtal series; determination of the preparation doses for white mice and pigeons. The experimental work on production of immunoglobulin against salmonellosis made it possible to develop a technological scheme of the analyzed preparation production. In course of the experiment there were found optimal conditions for serum fractionation; there were developed methods of its conservation, sterilization and quality control of the specific immunoglobulin.

In the conditions of the Republic of Belarus there was studied the activity of alaninaminotranspherase (AIT) and aspartate aminotransferases (AsT), alkaline phosphatase, lactic dehydrogenase, cholinesterase, alpha amylase in blood serum, liver and pancreas of 130-158-day old replacement chicks vaccinated against Newcastle disease. Research results showed that the most essential changes were observed from such enzymes, as AsT and AIT. Increasing of AIT activity in a liver, pancreas and blood serum of immunized hens was stated on the seventh day after vaccine administration. Character of changes can testify both the increasing of synthesis of the mentioned enzymes, and also their posttransmitting activation which took place due to intensification of transamination processes. Changes of activity of alkaline phosphatase, cholinesterase and alpha amylase were the most expressed on the 14th and 21st days of research. It was possible to assume, that there was a stimulation of synthetic function of hepatocytes under the influence of the vaccine. It was possibly the decreasing of enzymatic functions pancreas.