INFLUENCE OF FEED SUPPLEMENTS TO COW DIETS DURING FIRST 100 DAYS OF LACTATION ON MILK NUTRITIONAL VALUE

Currently, it has been understudied which forms of feed supplements ensure the most positive effect onincreasing milk nutritional value and processing properties. In this regard, an experiment was conducted in comparable groups of 90 cows. The animals of the 1st (control) group were fed compound feed concentrate that included the following ingredients: a rumen-protected fatsupplementMegalac (3.1%); a buffering agent -sodium bicarbonate (1.4%); protein digestion stimulator Farmatan TM (0.57%); mineral and vitamin premixRindavit 51 ATG RV (3.6%); the animals of the 2nd (trial) group were giventhe following feed supplements: protected fat Nutracor (3.0%); a buffer-ing agent Rumenbuffer (0.9%); protein-mineral-vitamin concentrate Cowfit 5 Plus (3.75%); mineral and vitamin premix Cowfit Immuno Fertil(0.75%). In the 2nd (trial) group, the levels of milk components increased as follow-ing: lactose -by 20%; butterfat -by 15%; casein -by 25%; calcium -by 33%; phosphorus -by 53%; copper by 45%, zinc -by 89%; vitamin A -by 67%; vitamin E -by 30%; that was indicative of milk nutritional value increase

METHOD FOR OBTAINING A PROTEIN-VITAMIN CONCENTRATE FOR DISEASE PREVENTION IN FARM ANIMALS

Regional feed supplies in Yakutia include hay stocks, succulent feeds, as well as own production and import of concentrated feeds to the republic. Main winter feeds include hay, silage, and haylage; in summer grass of natural pastures is available. Annual provision of livestock with nutrients reaches 60-65% of normal, which is a limiting factor for the development of the genetic potential of local cattle breeds in Yakutia. Understanding of general patterns in digestive processes and physiological and biochemical mechanisms of assimilation of nutrients was based on the results of the studies of domestic ruminant animals (cattle, sheep). Issues of increasing feed security remain urgent for agro-industrial production. The authors describe in detail a method of obtaining a protein-vitamin concentrate having pharmacological properties. Most of these processes involve gas components, liquid or solid substances. Complex hydrodynamic, thermal, and mass exchange processes occur simultaneously in fermenters. A method for expanding the production of feed protein using a combination of hydrodynamic and mass transfer characteristics and parameters with simultaneous optimization of the fermenter design and its operation modes is proposed, taking into account minimum energy consumption for oxygen dissolution and biomass production, based on technical capacity. Various types of devices are currently available; basically, they provide oxygen supply, as it is an integral part of device design, for the cultivation of microorganisms based on microbial synthesis. It should be emphasized that a fermenter is the main device of any microbiological production and largely determines its economic effectiveness. The obtained results will allow considerable acceleration of finalizing works for the development and improvement of perspective fermenter designs.

CLINICAL CHEMISTRY OF GRAIN-FED CATTLE. II. LIVER FUNCTION

The rate of plasma clearance of bilirubin (BCR), as a test of liver function, was followed in three hay-fed and four grain-fed Hereford steers over the first 77 days of a 106-day feeding period. The grain diet was 90% steam rolled barley, 5% beet pulp pellets and 5% of a protein/mineral/vitamin concentrate given together with a hay supplement of 0.9 kg/head/day. The grain was introduced slowly over a 10-day period. Fluctuations in hematocrit values occurred during the adaptation to the grain diet. Periodic episodes of markedly reduced liver function occurred synchronously in test animals during the introduction of the grain diet. Similar episodes of reduced liver function were observed with decreasing frequency and severity as the feeding progressed. After 25 days of grain feeding, loss of synchrony also occurred, so that high values were observed in only one test animal at any one time. As the feeding period progressed, the time required for the distribution and equilibration of the bilirubin in the blood increased in the grain-fed animals causing interference with the BCR tests. The effects on liver function indicated a reduction in the efficiency of the liver which probably contributes to pathologic conditions in feedlot cattle.

CHRONIC POISONING DUE TO EXCESS OF VITAMIN A

The clinical manifestations, the roentgenographic changes in the skeleton and the elevation of blood vitamin A are reported in a group of seven infants and younger children poisoned by ingestion of excessive quantities of vitamin concentrates A and D over periods of several months. The differential features of vitamin A poisoning and infantile cortical hyperostosis are discussed. Three types of vitamin concentrate A and D, commonly used in routine pediatric prophylaxis, were found to be toxic when ingested in sufficiently large quantities over sufficiently long periods. The minimal preclinical latent period of vitamin A poisoning was about six months and the minimal toxic daily dose was about 75,000 units. Excessive dosage was due to overenthusiasm for vitamins and ignorance of the dangers of high vitamin intake. The hazards of vitamin A poisoning from the routine prophylactic feeding of vitamin concentrates A and D to healthy infants and children on good diets are considerably greater than the hazards of vitamin A deficiency in healthy infants and children not fed vitamin concentrates.