The metabolic responses of equine articular cartilage to incubation with bacterial lipopolysaccharide (LPS) were studied, using explant cultures of articular cartilage obtained from the metatarsophalangeal joints of 15 horses, age of which ranged from 3 months to 20 years. For comparison, explants were also established from the metatarsophalangeal joints of 3 calves. Explants were cultured for 3 days in medium containing various concentrations of LPS from 0 (control) to 100 microgram/ml. Glycosaminoglycan (GAG) released during the 3-day incubation was determined by a spectrophotometric assay, using the dye 1,9-dimethylmethylene blue. Newly synthesized GAG content was assayed by measuring [35S]sulfate incorporation during a 3-hour pulse labeling period. In addition, prostaglandin E2 (PGE2) synthesis was quantified, using a [3H]PGE2 radioimmunoassay kit and magnetic separation. Finally, explants from 3 animals were used to evaluate the effect of supplementing culture medium with 5% serum on the response of explants to LPS, and explants from 1 horse were used to compare responses to stimulation with LPS derived from 2 bacterial sources. Equine explants cultured with bacterial LPS had a dose-dependent decrease in synthesis and increase in release of GAG, and these responses were significantly (P < 0.0001) greater in explants from younger horses. In addition, equine explants had a significant (P = 0.0001) dose-dependent increase in concentration of PGE2 released into the culture medium in response to incubation with LPS. Comparison of data for GAG synthesis from equine and bovine explants revealed a significant (P = 0.025) difference in responsiveness to LPS between the 2 species. Equine explants tended to have a greater suppression of GAG synthesis in response to incubation with increasing concentrations of LPS than did age-corrected bovine samples.

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