Hemodynamic effects of spontaneous ventilation, intermittent positive-pressure ventilation (IPPV), and high-frequency oscillatory ventilation (HFOV) were compared in 6 dogs during halothane anesthesia. Anesthesia was induced with IV thiamylal Na and was maintained with halothane (end-tidal concentration, 1.09%). During placement of catheters, dogs breathed spontaneously through a conventional semiclosed anesthesia circuit. Data were collected, and dogs were mechanically ventilated, using IPPV or HFOV in random order. Ventilation was adjusted to maintain PaCO2 between 38 and 43 mm of Hg during IPPV and HFOV. Cardiac index, aortic blood pressure, and maximum rate of increase of left ventricular pressure were significantly (P less than 0.05) less during HFOV than during spontaneous ventilation, whereas right atrial and pulmonary artery pressure were significantly greater during HFOV than during spontaneous ventilation. During IPPV, only the maximum rate of increase of left ventricular pressure was significantly less than that during spontaneous ventilation.

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.

A cross-sectional epidemiologic study associating air quality with swine health was conducted on 28 swine farms in southern Sweden. Correlation of housing air environment to swine diseases and productivity (data collected over the preceding 12 months) were investigated. The most prevalent swine health problems detected at slaughter were pneumonia and pleuritis. In farrowing and nursery operations, the most prevalent problem was neonatal pig mortality. Several air contaminants (dust, ammonia, carbon dioxide, and microbes) were found to be correlated with these swine health problems. Maximal safe concentrations of air contaminants were estimated on the basis of dose-response correlation to swine health or human health problems. Recommended maximal concentrations of contaminants were: dust, 2.4 mg/m3; ammonia, 7 ppm; endotoxin, 0.08 mg/m3; total microbes, 10(5) colony-forming units/m3; and carbon dioxide, 1,540 ppm. The overall quality of the ventilation system was correlated with lower concentration of ammonia, carbon dioxide, microorganisms, and endotoxin, but not with dust concentrations. High animal density was related to high ammonia and air microbe concentrations. Animal density measured as kilograms of swine per cubic meter (compared with kilograms of pig weight or swine per square meter) had the highest correlation to animal health and air contaminants.

An indexing system for hygiene variables associated with egg production was developed by use of datacollected from chicken flocks in southern California. The data were analyzed by factor and regression analysis. On the basis of our findings, hygiene index in relation to egg production consists of ventilation system, cooling system, manure removal, and truck movement. Flocks kept under natural ventilation produced, on the average, 2% more hen-day eggs than flocks kept under artificial ventilation. Flocks placed in houses with roof sprinklers produced 3.3% more hen-day eggs, compared with flocks placed in houses with inside foggers and pad. Flocks kept under the system of frequent removal of manure produced 2% more hen-day eggs than flocks kept under the system for which the manure was removed less frequently. Flocks kept in farms that restricted trucks collecting dead birds from entering the premises produced 3.4% more hen-day eggs than those that allowed such trucks to enter the farm.

Quail closed-house system is a house that support quails’ optimumrequirements as far as temperature, relative humidity, ventilation and light are concerned. One of the four units of quail closed-house systems at the Institute of Poultry Technology, Malacca was used in this study. The objective of this project was to evaluate the performance of the quail closed-house system by comparing the condition of the house under current management condition and after the Standard Operating Procedure determined by DVS was adhered. Thehouse performance was evaluated by observing its ability to achieve an optimum temperature range of 20°C to 27°C with a relative humidity between 60% to 80% as perfect surroundings for quails. At the end of the experiments, the results showed a decline in internal temperature at almost 3°C and increasing in a relative humidity of 10% after all the specifications and procedures were followed.

The present study objective was to determine whether ventilation of rats with room air is possible and whether this technique has advantages when compared to pure oxygen ventilation. Twenty rats were divided into two groups of ten animals each. In one group, the animals were ventilated with cylinder of compressed air, 0.21 of oxygen, (air group), while the other group animals were ventilated with cylinder of compressed oxygen, assumed 1.00 of oxygen, (O2 group). Blood gas parameters and oxygenation index were compared between groups. The O2 group had hyperoxia at the beginning and end of artificial ventilation. The PaO2 were adequate in animals of air group. No significant difference in PaCO2 was observed between the two groups at the beginning or end of mechanical ventilation. The mean oxygenation index (PaO2/FiO2ratio) was significantly higher in the air group compared to the O2 group at the beginning and end of artificial ventilation (5 min: p < 0.001 and 60 min: p < 0. In conclusion, ventilation of rats with room air is more advantageous than with pure oxygen since it permits adequate oxygenation without causing hyperoxia.

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

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

Results of realized in the conditions of the Republic of Belarus energy estimation of veterinary and hygienic methods of microclimate organization in livestock buildings were presented. As a result of the conducted veterinary and hygienic estimation of conditions of cattle maintenance in premises at cattle breeding farm in Vitebsk region (Belarus) it was found out, that one of the reasons of decreasing in productivity and livability of calves was the unsatisfactory microclimate at livestock buildings. In particular, air temperature in calf houses was marked below standard on 25-29%. Indices of the relative moisture exceeded the standard requirements on the average on 7% and concentration of ammonia - on 19-24%. Natural and artificial light exposure at premises did not correspond to veterinary and hygienic requirements. Research results analysis showed that a principal reason of unsatisfactory microclimate condition was the unsatisfactory system of ventilation, application of artificial prompting of air that involved the exceeding expenses for the electric power. The veterinary and hygienic measures with regard for power economy were characterized. It was stated that the proper use of ventilation, manure removing, feed-supplying and lighting systems made it possible to save up to 30% of power energy