Eight female piglets from each of three farrowed crossbred (75% Hampshire x 25% Local) gilts grouped as A, B and C were weaned at 28, 42 and 56 days respectively. Piglets of each weaned groups were divided into two sub-groups _ 'a' and 'b' consisting of 4 piglets in each. Piglets of sub-groups _ 'a' were supplemented with strategic mineral mixture while the piglets of sub-group 'b' were offered commercial mineral mixture. There was significant (P0.01) rise of serum oestradiol-17â at the pubertal oestrus compared to the levels before puberty in gilts. Oestradiol concentration did not differ significantly among piglets weaned at different days of age and between piglets supplemented with strategic and commercial mineral mixture. Serum progesterone was lowest during oestrus and highest on day 10 of the oestrus cycle in all the groups. Progesterone concentration in the piglets weaned at different days of age did not differ significantly. However, the level was found significantly (P 0.05) high in piglets supplemented with strategic mixture over the piglets supplemented with commercial mineral mixture.

Analysis of national studies and literary sources on problems of haemophilus pleuropneumoniae of swine was realized in the conditions of the republic of Belarus. Research was realized in the conditions of Agricultural Production Co-operative Uritskoe (Gomel region, Belarus). It was established that medical actions gave positive result only at early stages of disease.

Investigation of dynamics of indexes of carbohydrate and lipid exchange at piglets with various body weight at after weaning period, determination of possibility of their application as energy deficit markers, as well as studying the influence of vitamin and energy additive based on rapeseed oil on the indexes of carbohydrate lipid exchange in blood of piglets and their economic indexes were realized in the conditions of the Republic of Belarus. Research results showed that at the weaning period and after it there were changes in piglet organisms caused by adaptation to new housing conditions and that subsequently led to transformation of energy metabolism. After the weaning period there was stated increasing of level of lipid exchange in the energy supply of adaptation process, that was proved by the increased level of total lipids and triglycerides. Low indexes of carbohydrate and lipid exchange of the group piglets with low growth indicated to the insufficient level of energy supplying, needed for growth and adaptation. The studied vitamin and energy additives based on rapeseed oil corrected the level of carbohydrate and lipid exchange and could be used as a prophylactic agent against energy deficiency conditions of weaning piglets