The symptoms of photosensitization decreased rapidly in the stable and after 5 minutes a definite improvement was observed. Conclusion.-Since the reaction to sunlight in the sheep averaged with 0 · 25 gm. An area over the back of the sheep was shaved as described in the previous experiment.
The most severe clinical symptoms were observed in the sheep exposed during the incubation and reaction periods (group 2). Intramuscular hemorrhages in the diaphragmatic columns were noted in one sheep, a lesion which had not. The clinical symptoms in the exposed sheep were much milder than in any of the exposed sheep in the previous trials.
A summary of the various environmental factors affecting the sheep during the exposure periods in the previous four experiments is given in 'plot 1. may be briefly summarized as follows. These graphs also show the air temperatures measured in the stable and in the camp. 1 and 2 that the body temperatures of the sheep in the camp were usually lower at 7 a.m. and at 2 a.m.
A comparison of daily body temperature fluctuations measured in the camp and in the barn is presented in fig.
O. NEITZ AND GERTRUD RIEMERSCHMID
5, where the height of the columns indicates the number of sheep that showed the respective symptom, and the numbers at the bottom the number of days after the injection of the.
UNS-HORN
The total amount of radiation falling from sunrise to sunset over a period of 21 days was 11,520 gram calories per square centimeter, an average of about 550 grams. Body temperatures (Experiment 6). - The group average values of body temperatures for 6 o'clock in the morning are presented in fig. are presented in fig. 6.-Body temperatures of sheep with bluetongue disease and air temperatures at 6 a.m. 7.-Body temperatures of sheep with bluetongue disease and air temperatures at 1 p.m. sunrise at 5:50 a.m.) body temperatures were the lowest in both groups of shorn sheep during the first three days.
During the peak of the febrile response, all four groups of sheep showed very similar boy temperatures at that time of day, despite a relatively large difference (up to 12°F) in ambient air temperature. camp and in the stable. Once again it appears that this was not due to a difference in air temperature that was the same in both places, but that it must be attributed to the influence of solar radiation. This was also evidenced by the fact that on cloudy days the temperatures of the sheep in the camp approached those of the sheep in the stable, while on cloudless days the differences between the temperatures were more apparent.
7 is that in the camp and in the stable the sheared sheep showed higher temperatures than the unshorn during the height of the febrile reaction. The daily fluctuation of body temperatures was, as in the previous experiment, much greater in the exposed than in the barn sheep (see Fig.
This difference was very marked in shorn sheep, for which no satisfactory explanation can be given. 10.-Comparison of body temperatures between healthy sheep and those that reacted to the bluetongue disease in the barn. The remarkable fact is that this difference could. notice already on the first day the fact is that this difference could. seen on the first day after artificial infection, long before any sign of reaction to bluetongue disease has developed. shorn sheep with bluetongue showed a higher than normal body temperature during the first 14 days; higher than normal body temperature on uncut days; in uncut. in sheep it was only during the peak of the febrile reaction.
12.- Comparison of body characteristics between healthy sheep and sheep reacting to bluetongue in the camp. The variation in the different groups was similar to that observed in the previous experiment. In the exposed sheep, especially in the sheared group, the symptoms were even more pronounced than in the same groups during the previous test.
The respiratory rate of the sheep in the barn remained normal, but in the camp it showed a similar increase as in the previous experiment. In the two groups of normal sheep in the camp, the respiratory rate was not as high as in the immunized animals. 13.-Comparison of body temperatures between healthy sheep and those that reacted to the bluetongue disease in the camp.
Experiment 6.)-The details of the post-mortem examinations are given in Tahle 6 of the Appendix. In the normal sheep, which were killed at the end of the experiment, Oestrus ovis larvae could be detected. The trials on 120 sheep undergoing the bluetongue vaccine immunization process showed that body temperature responses and the incidence and severity of clinical symptoms were much more pronounced in the exposed sheep than in those kept in a barn.
When considering the difference in the environmental factors affecting the sheep in the stable and in the camp, not only solar radiation, but also air temperature, wind and rain had to be taken into account. The air temperature during the day showed very little difference in the two localities; however, after sunset the temperature in the camp dropped. However, during the day, when the air temperature in the stable and in the camp was almost equal, the clinical symptoms in the sheep remained constant in the stable group, while the severity increased in the camp in the afternoon and during the afternoon, when the solar radiation was very intense and the exposure had already lasted for several hours.
Whether this difference in the air temperature during the night has only had an influence on the course of the disease cannot be determined until a sufficient experiment has been carried out.
HYPERAEMIA EROSION SWOLLEN UPS NASALDISCHARGE COR.ONITI5
S'HORN
- Experiments \Yhich clearly indicate the rletrimental in-fluence of solar radiation on the course of bluetongue are described
- In order to Yer·ify these obserYations, t\YO experiments on a large scale (60 sheep each) were undertaken on sheep subjected to the immunizatiou
- The body temperatures and the natme of the clinical symptoms showed that the reactions were much more pronounced in the camp than iu
- Bronchopneumonia in sheep photoserisitized with methyleneblue occurred on several occasions and developed sometimes very rapidly. This
- During the course of the above investigations, multiple haemorrhages and muscular degeneration, a lesion which had not been p1·eviously associated
- The unthriftiness frequently observed iu sheep after immunization or natural infection can also be attributed to the muscular degeneration
- Since the infl.uence of solar radiation on the course of bluetongue has definitely been established, p articular attention should be paid to the time of
- The provision of shade for sheep which have been vaccinated or which contracted the disease naturally should be promoted wherever possible
- CLINICAL 0 SYMPTOMS
During two experiments it was observed that the increase in the severity of clinical symptoms during the day occurred even on calm days, where the influence of wind could be excluded. This observation and the fact that the air temperature is practically equal during the day in both localities proves that the deterioration of the condition of the sheep during the day can only be attributed to the influence of solar radiation. However, it is suggested that the heating effect of sunlight plays a dominant role.
During the course of the disease, the sheep were exposed to solar radiation for several hours every day. Exposure in winter (June) had practically no influence on the course of the disease. This observation provides an explanation for the general stiffness, torticollis and rigidity of the sheep responding to bluetongue.
Ulcers on the lips; subendocardial bleeding; edema under the skin of the back and intracutaneous hemorrhage1 of the spleen; mild degree of esophagostomiasis. hydropericardium; hydrothorax; subepi- and subendocardial hen and pulmonary edema; fatty degeneration of the liver; ac~. Hyperemia and pulmonary edema; bilateral bronchopneumonia; cl pigmentation of perijugular tissue and cecum mucosa1.
Cyanosis; severe hyperemia and edema of the lungs; acute bilmonia; hydropericardium; very few epicardial hemorrhages; h1 kidneys, small intestine and large intestine; superficial erosions at the bottom of the subcutaneous tissues, especially under the shaved area; bleeding from the trapezius and cutaneous muscles. Emaciation; mild anemia; mild hyperemia and edema of hydropericardium; hyperemia of the liver; , mild tumor splenia; intestinal tract and of the subcutaneous tissues under the sheared a]. Emaciation; mild anemia; coronitis; acute hemorrhagic enteritis; pigmentation of the pericular tissues with methylene blue; enlargement of the lymphatic glands;.
Killed on the 12th day from the multiple intramuscular hemorrhages in the cutaneous, brachio-cephalic and trapezius. 2 unshorn sheep, stable 5th day Hyperaemia of the oral mucosa; moderately swollen lips; superficial erosions on nostrum; slight edema of the lungs and 'tumor spleen. 5th day Hyperemia of the oral mucosa; swollen lips; superficial erosions on nostrum; tumor spleen; multiple localized hemorrhages in the longissimus dorsi.
12th day Mild hydropericardium ;· subendocardial haemorrhages; intramuscular bleeding in the columns of the diaphragm. 12th day Multiple localized bleeding in the subcutaneous tissue of the back artd in the chest muscles.
