The effect of feeding monensin, with or without dry hay plus wilted forage, on ruminal formation of 3-methylindole (3MI) was investigated in pastured cattle. Eighty-two cows were allotted to 3 groups. Cows of group-1 served as controls and were given a daily energy supplement (1 kg/head) without monensin for 1 day before and for 7 days after being allowed access to lush pasture. Cows of groups 2 and 3 were given the same daily energy supplement, which also contained monensin (200 mg/kg of supplement). Cows of group 3 also were fed dry hay for 5 days before the start of the study and continued to be given supplemental hay for 4 days after being allowed access to lush pasture containing a layer of wilted forage. Ruminal 3MI and indole concentrations increased on day 1 after all groups were allowed access to lush pasture. By day 7, 3MI concentration in all cows had decreased to pregrazing concentration. Indole concentration did not reach pregrazing concentration until day 10 for cows of groups 1 and 2. Group-3 cows had pregrazing indole concentration on day 7. Ruminal indole concentration did not differ (P > 0.05) between groups 1 and 2. Ruminal indole concentration was lower (P < 0.01) in group-3 cows on all sample collection days, except day 10, compared with that in the other groups. Monensin reduced (P < 0.01) 3MI formation on days 1 and 7 in group-2 cows, compared with group-1 cows. Group-3 cows had lower 3MI concentration than did group-1 cows (P < 0.01) on days -1, 1, 4, and 7. Monensin, when fed with dry hay and wilted forage, reduced (P < 0.01) 3MI formation on days 4 and 7 in group-3 cows, compared with cows that were only given monensin (group 2). Group-3 cows also had lower (P < 0.05) 3MI concentration, compared with group-2 cows on day 1. Results indicated that monensin reduced ruminal formation of 3MI. Feeding dry hay and wilted forage to cattle during the change to lush pasture resulted in further reduction in the amount of 3MI formed by ruminal microorganisms. To maximize the effectiveness of monensin in reducing 3MI formation, dry hay plus wilted forage should be fed to pastured cattle for at least 4 days after they are allowed access to lush pasture.

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%.