An experiment was conducted to compare the bioavailability of dl-alpha-tocopherol acetate (TA) with that of dl-alpha-tocopherol nicotinate (TN) when administered to sheep, as a single dose, either into the rumen or the peritoneal cavity. A total of 16 sheep were used in a factorial design, with 4 sheep/treatment at the interaction level. In addition, 5 sheep that received no supplemental alpha-tocopherol, were euthanatized at the end of the trial to provide baseline data for tissue alpha-tocopherol concentrations. Curves were fitted to the plasma alpha-tocopherol concentration values, taken over 180 hours after administration of the esters. Availability of TA was greater than TN, as evidenced by the significantly higher curve parameter values (P < 0.05) and tissue concentrations (P < 0.05). Route of administration had a marked effect on availability of TA (P < 0.001), but not of TN.

Oxytetracycline (OTC) pharmacokinetic values in plasma and bile were ascertained after IV administration of the drug. At 6 hours after administration of 1 mg of OTC/kg of body weight, 2.15% of the dose was found in the bile and 37.6% was found in the urine. At 2 hours after administration, the peak bile-to-plasma OTC concentration ratio was 60:1. Bioavailability of OTC was 47.6% when it was administered orally to fasted turkeys and was 9.4% when administered to fed turkeys.

Pharmacokinetic variables of skeletal muscle creatine kinase (CK) activity after IV administration of a muscle extract; CK bioavailability after IM administration of the muscle extract; and effect of IM administration of saline solution, to appreciate the possible release of CK consecutive to muscle puncture, were determined in 6 cows. A general equation for the quantitative estimation of skeletal muscle damage also was derived. Administration of saline solution IM had no effect on plasma CK activity (ANOVA, P > 0.05) in any of the cows. After IV administration of the muscle extract (150 U/kg of body weight), mean volume of the central compartment, plasma half-life, and plasma clearance of CK were 0.027 +/- 0.007 L/kg, 520 +/- 109 minutes, and 6.43 +/- 2.29 ml/kg/h, respectively. After IM administration (150 U/kg), mean bioavailability of CK was 51 +/- 17% and maximal plasma CK activity (500 +/- 97 U/L) was observed at 454 +/- 131 minutes. The rate of CK activity entry into plasma was determined by use of deconvolution analysis. Two peaks were observed; the first appeared before the 30th minute after IM administration, and the second appeared at 3.3 +/- 1.1 hours. Amplitudes were 6.31 +/- 4.45 and 6.57 +/- 3.08 U/kg/h, for the first and the second peaks, respectively. The quantity of CK liberated from control muscle was 0.69 +/- 0.12 U/kg/h, corresponding to a normal daily catabolism of 5.8 +/- 1.0 mg of muscle/kg. From these results, the following equation can be proposed to determine the corresponding mean equivalent of destroyed muscle (Qmuscle, test article) after IM administration of a test article: Qmuscle, test article (g/kg) = 4.41 X 10(-6) AUC (U/h/L), with AUC being the CK plasma activity area under the curve.

The pharmacokinetics and bioavailability of rifampin were determined after IV (10 mg/kg of body weight) and intragastric (20 mg/kg of body weight) administration to 6 healthy, adult horses. After IV administration, the disposition kinetics of rifampin were best described by a 2-compartment open model. A rapid distribution phase was followed by a slower elimination phase, with a half-life (t1/2[beta]) of 7.27 +/- 1.1 hours. The mean body clearance was 1.49 +/- 0.41 ml/min.kg, and the mean volume of distribution was 932 +/- 292 ml/kg indicating that rifampin was widely distributed in the body. After intragastric administration of rifampin in aqueous suspension, a brief lag period (0.31 +/- 0.09 hour) was followed by rapid, but incomplete, absorption (t1/2[a] = 0.51 +/- 0.32 hour) and slow elimination (t1/2[d] = 11.50 +/- 1.55 hours). The mean bioavailability (fractional absorption) of the administered dose during the first 24 hours was 53.94 +/- 18.90%, and we estimated that 70.0 +/- 23.6% of the drug would eventually be absorbed. The mean peak plasma rifampin concentration was 13.25 +/- 2.70 microgram/ml at 2.5 +/- 1.6 hours after dosing. All 6 horses had plasma rifampin concentrations > 2 microgram/ml by 45 minutes after dosing; concentrations > 3 microgram/ml persisted for at least 24 hours. Mean plasma rifampin concentrations at 12 and 24 hours after dosing were 6.86 +/- 1.69 microgram/ml and 3.83 +/- 0.87 microgram/ml, respectively. We tested 162 isolates of 16 bacterial species cultured from clinically ill horses for susceptibility to rifampin. All strains of coagulase-positive staphylococci, Streptococcus zooepidemicus, Str equi, Str equisimilis, Rhodococcus equi and Corynebacterium pseudotuberculosis were highly susceptible to rifampin (minimal inhibitory concentration [MIC] less than or equal to 0.25 microgram/ml).

Napier grass (Pennisetum purpureum) has been the most promisingand high yielding fodder giving dry matter yields. This experiment was conducted to determine the effect of cutting intervals on the yield and nutrient composition of six cultivars of Napier grass (Pennisetum purpureum) which is 3rd Generation Napier, India Napier, Kobe Napier, Red Napier, Taiwan Napier and Zanzibar Napier. The grasses were cut close to the ground levelto get a uniform stand on day 70 after planting and the cutting intervals were at 35 and 42 days and carried out for 3 times.After each harvest, the rates of maintenance fertiliser used were 150 kg of nitrogen, 60 kg of phosphorus and 100 kg of potassium per hectare per year. Harvested plant material was weighed, pre-dried in a forced-air drying oven at 60 °C overnight before grinding. Ground samples were used to determine dry matter (DM), crude protein (CP), crude fibre (CF) and metabolised energy. The data were analysed using Statistical Analysis System (SAS™) followed by Tukey’s post-hoc test. AP value of less than 0.05 (p<0.05) are considered statistically significant. Results showed that increasing the cutting interval (i.e. advancing age of maturity) increased dry matter and crude fibre significantly.However, in terms of nutrient content, crude protein and metabolised energy percentage was markedly decreased as thecutting interval increased. From the results presented, it is clear that cutting a stand of Napier grass at 35 days will achieve greater yield and nutrient content.

This study was conducted to investigate whether dietary enzymes alter the caecal microbial profile of broilers fed sorghum-based diets. Four sorghum-based diets (918 g sorghum/kg diet) were prepared. One was the control diet and three had enzymes (xylanase, phytase andprotease) added. Broilers, 35-day-old, were reared (8 birds/cage) in an environmentally controlled shed and randomly allocated to replicated (n=4) assay diets and free access to feed and water all time. On day-42, birds were euthanized and caecal contents collected, pooled on a per/pen basis and frozen (-20 °C). The DNA was extracted from caecal samples using a bead-beating protocol and the V2V3 regionof the bacterial 16S rRNA gene amplified by PCR. Amplicons were separated on sequence difference using Denaturing Gradient Gel Electrophoresis (DGGE) and microbial profiles generated and compared.The DGGE profiles, when analysed, indicated that there was approximately 80% similarity between caecal microflora in all types of the diet treatments. This suggests that there was no overalldifference between any of the profiles and therefore the addition of different types of feed enzymes in a sorghum-based diet had no impact on the overall composition of the broiler caecal microflora.

In the conditions of the Republic of Belarus there was determined the productivity and foraging advantages of fodder galega (Galega officinalis) in comparison with the traditional perennial leguminous grasses (alfalfa (Medicago sativa); alsike clover (Trifolium hybridum); cookshead (Onobrychis viceaefolia)) and influence of the analyzed crop of state and internal microbiota of agricultural animals. There was studied the qualitative structure of galega in accordance with the phases of crop development and its influence on physiological functions of animals. It is established, that in the conditions of northern region of Belarus the fodder galega provided the yielding capacity of dry matter of 11,3 t/ha that exceeded the indices of alfalfa on 13,9%, alsike clover - in 2,7 times and cookshead - in 2,1 times. By the third decade of May it formed 18-20 tons green mass that made it possible to feed animals on 10-15 days earlier, than with other leguminous grasses. High degree of leafage (65,7%) preconditioned its high nutritional value. Fodder galega has high level of calcium, potassium, phosphorus and some microelements: copper, zinc, manganese, cobalt. Studying of vitamin value of fodder galega showed that its green mass was vitamin-rich, had enough of irreplaceable amino acids. It was established, that hay of fodder galega had high level of the non-decomposed protein (68,6-71%) that was very important for feeding of highly productive cows. It increased the level of crude protein in experimental animals on 8%.

Belarus is included into number of the leading countries of the world which provide the increasing of the expansion rates of milk production and dairy products on a per capita basis. However, the agricultural enterprises of the Republic of Belarus annually spend approximately 800 thousand tons of whole milk that makes about 20% from the general milk yield for manufacturing expenditures in the process of livestock operation. The purpose of research was working out of a new premix structure and zootechnic requirements to its use in structure of milk replacer, produced on hydrodynamic installation. The optimum doses of amino acids, vitamins and mineral substances promoted the increasing of calves daily average weight gain during the dairy period on 5,4% (788,5 g instead of 748,1 g), reducing of expenses for forages per 1 kg of weight gain - on 6,5% (2,9 fodder units against 3,1 fodder units) and the decreasing of the prime cost production for fodder expenses - on 4,7%. There was presented the composition and nutritive value of the analysed whole milk replacer. Usage of local sources of protein-fatty raw materials of plant origin, and also secondary resources of processing of whole milk in the content of milk replacer for young cattle allows to completely refuse from expensive components delivered from abroad and to lower their cost

Research on preserving ability of the biological preserving agent Bioplant for grass and maize silage making was realized in the conditions of the Republic of Belarus. Application of Bioplant in course of grasess and maize encilaging promoted the faster accumulation of the significant amount of milk acid and decreasing of рН up to 4,1-4,2. Silage which was prepared with preserving agent Bioplant corresponded to the top grade of quality. Application of Bioplant for preparation of siloed forages promoted the reduction of losses at their storage. For example, in grass-legume and cereal silage there was a reduction of dry matter losses in comparison with control silage - on 4,7 and 4,2%, crude protein - on 5,6 and 5,0%, respectively. In maize silage the addition of the preserving agent there was stated the decreasing of nutrient losses in comparison with the control: dry matter - on 5,2%, crude protein - on 6,2%. Feeding of wedder hogs with the silage preserved by the preserving agent Bioplant provided higher digestibility of crude protein in comparison with the control group: on 3,2% in the conditions of grass-legume silage use, on 2,4% - in the conditions of feeding with cereals, and on 2,9% - in the conditions of feeding with maize silage

There was studied the width of distribution and peculiarity of clinical manifestation of mineral exchange diseases at pregnant sows, and also perfection of preventive actions at pathology of mineral metabolism in the conditions of prophylactic medical examination. Results of research have shown, that diseases of mineral metabolism widespread (84,7%) among pregnant sows in the conditions of industrial production, are most extended scarce conditions on Zn (17,7%) and Fe (22,5%). Clinically this insufficiency was expressed by oppression, appetite distortion, occurrence on a skin of specifically red stains correct roundish the form: with the clarified sites in the centre, are registered as abortions at final stages of pregnancy. It is established, that the way of preventive maintenance of hypomicroelementosis of pregnant sows with use of chelated forms of microelements is more preferable than sows, as reduces percent of clinical display of Zn and Fe deficiency, stabilize level of hematological and biochemical indicators of blood more effectively, and also raise industrial indicators of pregnant sows. | Целью работы было изучение широты распространения и особенностей клинического проявления заболеваний минерального обмена у супоросных свиноматок, а также совершенствование профилактических мероприятий при патологии минерального обмена веществ в условиях диспансеризации. Результаты исследований показали, что болезни минерального обмена веществ широко распространены (84,7%) среди супоросных свино¬маток в условиях промышленного производства, наиболее распространены дефицитные состояния по Zn (17,7%) и Fe (22,5%). Клинически эта сочетанная недостаточность выражалась угнетением, залеживанием, понижением и извращением аппетита, появлением на коже специфически красных пятен правильной округлой форма: с просветленными участками в центре, зарегистрированы так же аборты на конечных стадиях супоросности. Установлено, что способ профилактики гипомикроэлементозов супоросных свиноматок с использованием хелатных форм микроэлементов предпочтительнее, поскольку сокращает процент клинического проявления дефицита цинка и железа, эффективнее стабилизируют уровень гематологических и биохимических показателей крови, а также повышают производственные показатели супоросных свиноматок.