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Like other fatty oils from plants, olive and peanut oils, the most commonly used vehicles for the injection of juvenile hormone and its analogs, contain substances that show effects similar to those of this hormone. A dose of olive oil smaller than that used to dissolve a single injection of juvenile hormone will cause nuclear enlargement in the cells of the prothoracic gland of the desert locus and advance the succeeding molt.  相似文献   
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The procedures of manual and machine catching acted as short-term stressors, and induced a state of fear in 8-week-old broiler chickens. The heart rate of birds caught by both methods rose to similar high values but that of birds caught by machine returned to near normal rates more quickly, suggesting that they were less stressed. The duration of tonic immobility, a response which increases with fearfulness, was much longer in manually-caught birds. These results suggest that stress could be reduced and welfare improved by catching and picking up broiler chickens by a carefully designed machine, rather than by hand.  相似文献   
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The causes of perinatal mortality in farmed fallow deer in the Camden region of New South Wales were determined between 1982 and 1987. The results of 144 necropsies on fawns showed that ante-parturient and parturient deaths occurred in 33 (22.9%) of cases, with post-parturient deaths accounting for 99 (69.8%), and undiagnosed causes the remaining 12 (8.3%). The most common cause of post-parturient death (43.1%) was exposure/starvation of fawns that had birthweights lower than the average for surviving fawns on these same farms (3.01 kg and 4.12 kg, respectively). These results provide good evidence of the correlation between low birthweight and perinatal mortality in fallow deer on Australian deer farms.  相似文献   
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A method for systematic examination of the livers was developed, based on identification of the hepatic and portal veins in sixteen dogs. The right medial, quadrate, left medial and lateral hepatic veins and the hepatic branches of the portal veins were easily located with the dog in dorsal recumbency. The right lateral and caudate hepatic veins were identified more easily from the right side with the transducer positioned between the ninth to the eleventh intercostal spaces. Visibility was affected by the fullness of the stomach but this effect could be minimized by changing the position of the transducer to select a more suitable anatomical approach. Identification of the two systems depended on their echogenicity, the anatomical position of the main branches and their pattern of distribution. As in humans, the portal veins were in general, more echogenic than the hepatic veins and the hepatic veins could be traced from their junctions with the caudal vena cava. Identification of the branches of the hepatic and portal veins was complicated by the anatomical shape, the nutritional status and respiratory stage of the animal. A systemic approach based on a knowledge of the distribution patterns produced by the hepatic and portal veins ensures that all liver lobes are identified and all important structures are assessed.  相似文献   
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