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The influence of various ranges of dry cooling /average 22,1 mW/cm² - BCD and 60,2 aW/cm² - CD/ on the heat management have been studied in 15 rabbits. They were exposed to various ranges of temperature and air movement. The skin temperature at shorn and not shorn sites and heat flow were measured. The effect of cooling and air movement on skin temperature, thermal gradient and external thermoinsulation were calculated using statistical methods. It has been found that cooling, especially CD, clearly reduced the skin temperature, whereas the influence of air movement on skin temperature has been susceptible of various interpretations. Thermal gradients /skin temperature - air temperature/ increased as the cooling rlsed but their increase was higher at lower values of cooling /BCD/ than at higher values /CD/. The same relationship could be found in case of heat flow. The external insulation was dependet on cooling and at higher cooling values /CD/ it was lower than at lower values of cooling /BCD/. It proves that lower critical temperature for rabbits was exceeded when the experimental factor /CD/ appeared.
The purpose of study was the evaluation of different types of measurers /surface temperature and heat flux intensity measurers/, especially detectors connected to apparatuses, to determine the usefulness for the studies on the thermoregulation processes in animals. Besides of testing of devices, the selection of measurement sites on the surface of animals, which could be the most accurate for the demonstration of thermal variations, was done. The study included the manner of data collection, like the way of the detectors placement on the surface of body, the proper time needed to take the readings, results repetition and the methods of animal restriction.
Investigations were conducted on two groups of dairy cows, housed into the structures differed considering the systems of feeding and maintenance /structure I was free-stand, concrete barn; structure II - tethered, litter bedding barn including pasture during summer/. Cows selected for an experimental trials, /3 and h months of pregnancy/, were clinically examined and the blood was taken for hematology and biochemistry assignments. The procedure was repeated in 8 and 9 month of pre-delivery period. The quality of silage, fed during the pregnancy, was estimated. Among of blood indicators, the greatest variations from the physiological standards were referred to ketone bodies and' acid-base balance parameters. One can suppose, that the reason of variations was the a low quality of silage, composed too large part of cows diet. Evaluating the course of periparturient period, it appeared, that increased level of ketone bodies and acid-base balance disorders, were accompanied by the frequent number of disease incident's, like placenta detention, uterine mucus membrane inflammation, post-parturition paralysis, delayed uterus involution and udders inflammation.
The purpose of study was to determine the effect of supplements added to the diet of cows during the "dried" period, on the subsequent milk production and offspring performances. The IInd experimental group of cows was fed with MONOMIX supplement, the IIIth group with Na₂HCO₃+MgO, the IVth group with B-composition, while the Ist group was settled as a control. It was concluded, that both, MONOMIX and Na₂HCO₃+MgO supplements had an advantageous influence on milk yield in cows, because the level of lactation in these cows was higher when compared to the previous production. Calves delivered from MONOMIX cows were characterized by the highest growth parameters, moreover, the highest total protein and gamma-globulin level were assigned in blood serum.Reversely, the lowest daily gain, total protein, gamma-globulin, glucose, carotin levels and the lower AP activity were found in those calves born from cows assigned to the Ist /control/ group.
Celem pracy były badania dotyczące wielkości strat ciepła zachodzących z organizmów owiec w zależności od warunków meteorologicznych środowiska oraz przewodnictwa cieplnego ich runa. Wykonano je u 5 dorosłych owiec w 3 fazach - przed strzyżą, bezpośrednio po strzyży oraz po kolejnych 4 miesiącach i częściowym odroście runa. Badano temperaturę rektalną (tr), temperaturę skóry w 7 punktach termostabilnych (ts) i 5 termolabilnych (tl) oraz wielkość przepływu strumienia ciepła całkowitego (QT), konwekcyjnego (QC) i radiacyjnego (QR). Jednocześnie wykonano pomiary warunków mikroklimatycznych: temperatury powietrza (tp), wilgotności względnej (f) ochładzania suchego (H) i prędkości ruchu powietrza. Analizując układ ich wartości stwierdzono, że poza f odbiegały one od normatywnych, co narażało owce na zbyt duże straty ciepła z ich organizmów. Jeszcze większy wpływ na wielkość tych strat miało runo owcze. W okresie po strzyży u owiec pozbawionych tej izolacji termicznej dochodziło, przy niesprzyjających warunkach bioklimatycznych, do zachwiania u nich bilansu cieplnego organizmów.
The exchange of heat energy between the body and the environment in homothermal animals depends among others on the temperature gradient. The increase in the body and skin temperature caused by the decrease in the ambient temperature is to reduce the thermal gradient which protects animals against stress of heat and cold. In the present study the authors examined the rate of changes of thermal gradient between the skin and the environment and changes in skin temperature, the rate of heat flow and insulating power of hair cover in rabbits according to the changes of environmental temperature. The measurements were made at various sites of the skin: thermostabile and thermolabile, not shorn and shorn. Considerable dopendence of skin temperature on the environmental temperature, especially at the thermostabile sites, shorn has been observed although the drop in skin temperature did not catch up with the drop in air temperature. The values of those gradient influenced the value of heat flow from the body to the environment.
The temperature of the skin surface was measured with a termistor thermometer /Leeds and Northrup/. The studies embraced six halfblood and six primitive horses. The range of skin temperature was from 20.3 to 30.3 degrees C. /halfbloods/ and from 25.3 to 31.3 /primitive horses/. Sites selected on the body surface were divided into thermostabile and thermolabile places. The results were elaborated statistically. The dependence of the temperature of these sites on meteorological factors was indicated. There was however no essential dependence either between the skin temperature and other investigated physiological factors or between the two groups of horses.
The study concerned the development of thermoregulation in calves at age of 1 to 50 days of life. Rectal temperature /tr/, skin temperature at thermostable /ts/ and thermolabile /tl/ sites and heat flux /Q/ at these points were measured. At the same time, microclimatic conditions of barn /t, e, f, V, H/, were controlled. One concluded some independence of rectal temperature from the age of animals and slight relationship between tr and skin temperature. Together with the animal growth, skin temperature at thermostable points increased, whereas at thermolabile sites decreased. Moreover, decreasing correlation between skin temperature and cooling factor was demonstrated, what can suggest the development of thermoregulatory abilities in calves. Heat flux was markedly correlated with skin temperature.
The purpose of the study was to determine the degree of interrelationship between the udder surface temperature, heat flux and microclimatic conditions in the cow-shed, and different periods of lactation. A considerable diffe- rentation of udder temperature was found depending on the place of measurement. The highest temperature was found in the milk antrum and the lowest at teats. Udder skin temperature and the magnitude of heat flux from its surface were dependent mainly on air temperature, air velocity and cooling. External udder temperature was the lowest at air temperature ranging from 16.4 to 17.4°C. At the same time heat flux from the udder surface was the highest. Above the temperature range there occurred an increase of skin temperature and the value of heat flux decreased. The highest temperature of the udder was observed at 6-7 months after delivery, although that increase could have been the outcome of seasonal air temperature growth during that period. No marked influence of lactation period on the biothermic indices of the udder was found.
17 thermostabile and 9 thermolabile sites were used to measure the skin and body surface temperatures and the heat flux flow of 12 dairy cows. Obtained data supplied Burton's indicator of blood circulation, external and internal thermal insulation. Results indicate that in the range of the trunk /thermostabile sites/ the anterior body parts of examined cows were warmer than their posterior parts; the thermal situation was contrariwise as regards limbs /thermolabile sites/, where the fore legs were warmer than the hind legs. The remaining biothermal indexes corresponded to the temperature levels of the skin and body surface: the warmer parts were characterized by higher values of heat flow and Burton's circulation indicator only by lower levels of thermal external and internal insulation than the cooler parts. Differences between the warmer and cooler body parts of animals were statistically essential in relation to each of the discussed factors.
Celem pracy było określenie wpływu dodatków paszowych, takich jak kwasy huminowe wyekstrahowane z węgla brunatnego oraz ich mieszanki z węglem brunatnym, torfem i kaolinem lub tymi trzema kopalinami łącznie, na rozwój i zdrowotność cieląt, kształtowanie się parametrów biochemicznych w surowicy krwi oraz stan równowagi kwasowo-zasadowej. Stwierdzono, że wszystkie dodatki wykazywały właściwości przeciwbiegunkowe, a najkorzystniej na przyrosty masy ciała wpłynął dodatek kwasów huminowych z kaolinem i węglem brunatnym, natomiast dodatek kwasów huminowych łącznie z węglem brunatnym miał działanie długotrwałe i powodował wyrównanie zaburzeń stanu równowagi kwasowo-zasadowej.
Przedmiotem badań bylo określenie wpływu wybranych parametrów mikroklimatu pomieszczenia na podstawowe wskaźniki termoregulacji fizycznej i podstawowe parametry fizjologiczne u cieląt w pierwszych 20 dniach ich życia i u dorosłego osobnika. Na podstawie uzyskanych wyników i wyliczonych zależności stwierdzono wpływ temperatury powietrza na temperaturę skóry cieląt w punktach termostabilnych i termolabilnych oraz na temperaturę wewnętrzną ciała. U osobnika dorosłego nie odnotowano wpływu mikroklimatu na temperaturę rektalną Ponadto u niego stwierdzono wpływ ochładzania suchego na wskaźnik ukrwienia skóry punktów termolabilnych oraz wpływ tp na liczbę oddechów, co mogło świadczyć o sprawniejszym fiinkcjonowaniu u niego mechanizmów termoregulacji fizycznej w przeciwieństwie do badanych cieląt.
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