From 2 to 4.5 months of age, 80 crossbred gilts were reared in a conventional grower unit where they were naturally exposed to mycoplasmal and bacterial pathogens that cause pneumonia and atrophic rhinitis. At 4.5 months of age, gilts were moved to environmentally regulated rooms (4.9 X 7.3 m) and assigned at random to 1 of 2 treatment groups: low aerial concentration of ammonia (4 to 12 ppm; mean, 7 ppm) or moderate aerial concentration of ammonia (26 to 45 ppm, mean, 35 ppm). Low concentration of ammonia was obtained by flushing of manure pits weekly, whereas moderate concentration of ammonia was maintained by adding anhydrous ammonia to manure pits that were not flushed. Gilts were weighed biweekly. Mean daily gain (MDG) was less (P < 0.01) for gilts exposed to moderate concentration of ammonia than for gilts exposed to low concentration of ammonia after 2 weeks in their respective environments. By 4 and 6 weeks, however, MDG was similar between the 2 treatment groups. After 6 weeks in these environments, 20 gilts from each treatment group were slaughtered, and prevalence and severity of lung lesions and snout grades were determined. At slaughter, body weight was greater (P < 0.01) in gilts exposed to low, rather than moderate, ammonia concentration (94.5 vs 86.8 kg; SEM, 3.3 kg). Percentage of lung tissue containing lesions (18 vs 12) and snout grade (2.8 vs 3.1) were similar between gilts exposed to low or moderate concentration of ammonia. The remaining 20 gilts in each treatment group were maintained in their respective environments, exposed daily to mature boars and bred at first estrus. Age at puberty was similar between gilts exposed to low or moderate concentration of ammonia (208 vs 205 days; SEM, 1.3 days), even though weight at puberty was less (P < 0.03) for gilts exposed to low concentration of ammonia than for gilts exposed to moderate concentration of ammonia (109.7 vs 118.2 kg; SEM, 4.5 kg). At day 30 of gestation, number of live fetuses (10.6 vs 11.7), fetal length (2.53 vs 2.57 cm), and fetus-to-corpus luteum ratio (0.85 vs 0.78) were similar between gilts at low and moderate ammonia environments. These data indicate that exposure of gilts to mean aerial ammonia concentration of 35 ppm in environmentally regulated rooms depressed MDG for 2 weeks, but failed to alter onset of puberty or litter size at day 30 of gestation.

Environmental variables in 10 commercial turkey confinement buildings, representing 2 natural ventilation designs, were measured during summer and the following winter. Sliding doors spaced at intervals along the walls of 5 of the buildings provided about 35% opening, and continuous wall curtains provided 60 to 80% opening in the other 5 buildings. Environmental variables assessed included airspeed; temperature; relative humidity; gases; particle number, size, and mass per cubic meter of air; and colonies of bacteria, yeasts, and other fungi per cubic meter of air. Colonies of yeasts and other fungi were quantitated in feed and litter. For most of the variables evaluated, significant differences were not attributable to building ventilation design; however, in winter, the total mass of particulate matter per cubic meter of air was higher in the curtain-type houses, compared with sliding door-type houses. Ammonia concentration in the air of sliding door-type houses progressively increased during summer and winter sampling periods. A significant effect of building ventilation design on turkey performance was not detected when using mortality, average daily gain, feed conversion, condemnations at slaughter, or average individual bird weight as measures of production.

Results of researches are stated according to efficiency of various ways warmed pigs. It is established, that application of warmed panels allows forming more comprehensible conditions of rest for pigs. Thus within 31 days at 137,13 kw – hour or the charge of the electric power on heating of one jack of pigs is reduced to 68,48% in comparison with use of lamps of infra-red radiation without essential decrease of growth rate and safety of young growth

During the sanitary-hygienic evaluation of livestock-rearing farm building (cow kennel and calf pens) by means of industrial and traditional technology there were revealed the infringements of constructive and exploit matter in ventilation system which proved to be the reason for formation of dissatisfactory stable climate. In case of the appropriate estimation, adherence to specification of ventilation construction and rather attentive attitude to the problem of ventilation regulation there could be obtained the positive results in optimization of air medium in animal husbandry houses. Support of air physical properties in livestock houses at the optimum hygienic level was possible only by means of ventilation and a choice of construction materials corresponding to the veterinary and hygienic requirements. The necessity of heat accumulation in livestock houses unites all mentioned above requirements. In some animal husbandry farms in the Republic of Belarus there was applied the mechanical ventilation. However, it was a great mistake to install only the air-moving device without heat exchanger installation. Therefore, an important point for optimization of microclimate livestock houses should be the determination of building thermal balance

In the pig enterprises of Belarus the most widespread sources of heat for pigs heating proved to be the infrared radiation lamps. In recent years there was stated the wide application of electric heated rugs of various designs or the electric heated floors. The special brooders, equipped with various sources of heat, passed the experimental check possibility of use for heating of pig houses. Their advantage was in decreasing of heat losses in the sleeping areas of pigs that demanded lower expenses of energy for heating of stores. However, till the present the effective brooder design, which could be convenient in use, cheap, easily sanitized and providing an optimum microclimate for piglets, was not offered for the production yet. Agricultural enterprise Kadehks has developed a design and the pre-production model of a warmed den for pigs under the name Logovo Dlya Porosyat UKhL-4 (Logovo). Application of brooder Logovo in combination with the warming plate made it possible to design more favorable mode for sleeping areas of pigs, to reduce preheating time of plates up to 10 days, to save (in comparison with incandescent lamps) up to 155 kw/h of electric power used for heating of pig sleeping area without decreasing their growth rate and safety. Application of the presented device in combination with heating plates made it possible to reduce the expenses for pig production and for the equipment of heating plates temperature regulators. Application of the differentiated heating mode with the possibility to deactivate the heating plates from the electric power sources after 10 days of the suckling period made it possible to lower the expenses for production of female socket of pigs

The researches were carried out in 2005-2006 at swine complex Zazerye of Mozyr region (the Republic of Belarus), that counts 54 thousand heads annually. The aim of the research is to develop perfect ventilation systems in reconstructed buildings for farrow and weanlings growing, that will provide resource saving and comfort conditions for animals. It is determined that providing perfect microclimate in buildings and energy spends cut for this climate creation in winter period is possible if technological qualities of fence constructions is higher from 0,97 to 2,5 m2 and natural ventilation is used. Microbe semination of the buildings for farrow and weanlings growing at this periods is 1,4-3,6 times lower. During the summer the combination usage of natural and imitation air ventilation is necessary

Perfect norms of floor area and feeding front are determined for replacement heifers on free stall management. These norms promote creation of more comfortable conditions of management, increase of average daily live weight gains at 9,1%, hemoglobin content – at 4,8%, erythrocyte quantity – at 6,3%