Activity of amylolytic, proteolytic, and lipolytic enzymes in the content and mucosa of intestinal tract, alkaline phosphatase in mucosa of intestinal tract, as well as the determination of calcium and phosphorous concentration in gastro-intestinal tract of hens were analyzed in the conditions of the Republic of Belarus. Results of analysis of the obtained experiment results of laying hens of parental stock by influence of various vitamin-mineral additives were presented. The highest activity of amylolytic, proteolytic, and lipolytic enzymes in 170-330 days old laying hens of Belarus-9 cross was marked in small intestine. There was stated the decreasing of enzymatic activity in proportion to removal from a stomach. At the same time, activity of alkaline phosphatase decreasds. Activity of alkaline phosphatase, proteolytic and starch-reducing enzymes in a mucous membrane of a duodenal gut was a bit higher than in mucosae of jejunal. Lipolytic enzymes showed high degree activity in mucosae of jejunal. Enzymic activity in large bowel was low. Addition of iodine-containing preparation Kajod into hen layer diets increased the activity of alkaline phosphatase, of amylolytic, proteolytic, and lipolytic enzymes in intestines. Enzymic activity of mucous intestines at hens of breed Plimutrok in process of removal from stomach decreased. In course of the period from 240 to 330-days old age the activity of studied enzymes in hen intestines decreased. Replacement of mineral additive Cockleshell by Pikumin did not render negative influences on changes in digestive enzyme activity. In 170-days old laying hens of Belarus-9 crossbreed the calcium content increased from the stomach to the small intestine, and then decreased in thick department. In the 200-days old hens the calcium concentration in a stomach increased in both groups and gradually decreased in the department of small intestine, but in rectum its quantity increased in both groups. In the period of intensive egg-laying (280 days) the general calcium content in thin department of intestines was less than in the stomach, later it increased in cecum and decreased in rectum. By the end of the experiment (330 days) the concentration of calcium in control group decreased from the stomach to the beginning of thick department of intestines, but in rectum its quantity increased. In experimental group the calcium content increased from a stomach to cecums and then decreased in rectum. In distribution of inorganic phosphorus in gastrointestinal tract departments at hens of various age groups the tendency to increase in its quantity in small intestine and the beginning of thick department of intestines, and then to reduction in rectum was observed. And at hens receiving premix Ajdeko, the phosphorus content, since 200-day age, was higher, than at hens receiving the basic ration

There was studied the activity of alaninaminotransferase and aspartataminotransferase, alkaline phosphatase, gamma-glutamiltranspeptidase, lactate dehydrogenase, cholinesterase, alpha amylase in blood serum, liver and pancreas of replacement young hens. At carrying out of immunization of replacement young hens by a vaccine against infectious laryngotracheitis, developed in Institute of experimental veterinary science, reaction from the party not only bodies of immune system, but also such bodies, as liver and pancreas, takes place. Biochemical reaction of the specified bodies to immunization is a consequence of adaptability of an organism to vaccinal stress. Biochemical changes of display enzymes in blood serum, pancreas and liver are found out. It was marked increase of activity of the given enzymes in liver, pancreas and blood serum so, activity of alaninaminotransferase and aspartataminotransferase, alkaline phosphatase, gamma-glutamiltranspeptidase, lactate dehydrogenase increased at birds of trial group in 1,3-1,9 times in comparison with the control. In the tabular form data on activity of alaninaminotransferase, aspartataminotransferase, alkaline phosphatase in liver, pancreas and blood serum of repair young growth of the hens vaccinated against infectious laryngotracheitis are presented. | Целью наших исследований явилось изучение активности аланин- и аспартатаминотрансфераз, щелочной фосфатазы, гамма-глутамилтрансферазы. лактатдегидрогеназы, холинэстеразы, альфа-амилазы, в сыворотке крови, печени и поджелудочной железе ремонтного молодняка кур. При проведении иммунизации ремонтного молодняка кур вакциной против инфекционного ларинготрахеита, разработанной в Институте экспериментальной ветеринарии им. С.Н. Вышелесского НАН РБ имеет место реакция со стороны не только органов иммунной системы, но и таких органов, как печень и поджелудочная железа. Биохимическая реакция указанных органов на иммунизацию является следствием адаптивности организма к вакцинному стрессу. Выяснены биохимические изменения индикаторных ферментов в сыворотке крови, поджелудочной железе и печени. Отмечалось сочетанное повышение активности данных ферментов в печени, поджелудочной железе и сыворотке крови, так, активность АлТ, АсТ, ЩФ, ЛДГ, ГГТФ повышалась у птиц опытной группы в 1,3-1,9 раза по сравнению с контролем. В табличной форме представлены данные по активности аланинаминотрансферазы (АлТ), аспартатаминотрансферазы (АсТ), щелочной фосфатазы (ЩФ) в печени, поджелудочной железе и сыворотке крови ремонтного молодняка кур, вакцинированных против ИЛТ