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111.
112.
Klopfer LE 《Science (New York, N.Y.)》1986,232(4753):1010-1011
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Pemphigus foliaceus of the footpads in three dogs 总被引:1,自引:0,他引:1
P J Ihrke A A Stannard A A Ardans C E Griffin A J Kallet 《Journal of the American Veterinary Medical Association》1985,186(1):67-69
Severe hyperkeratinization and villous hypertrophy of the footpads were seen in 3 middle-aged dogs. Peeling, fissuring, swelling, and ulcerations were noted on the margins of severely affected pads. Pain was evident in palpation and ambulation. Lesions were compatible with the traditional diagnosis of "hard pad disease". Histopathologic findings were diagnostic for canine pemphigus foliaceus in all 3 dogs, and direct immunofluorescence in an intercellular pattern was seen in both dogs that were tested. All 3 dogs responded to immunosuppressive dosages of corticosteroids. 相似文献
118.
The modern role of meat inspection and food hygiene 总被引:2,自引:2,他引:0
Feltmate TE 《The Canadian veterinary journal. La revue veterinaire canadienne》1985,26(1):29-32,33
119.
Sources of variation and prospects for improvement of productive efficiency in the dairy cow: a review 总被引:4,自引:0,他引:4
D E Bauman S N McCutcheon W D Steinhour P J Eppard S J Sechen 《Journal of animal science》1985,60(2):583-592
In this review, "productive efficiency" in dairy cows is defined as the yield of milk obtained in ratio to the nutritional costs associated with maintenance, milk synthesis and loss of body condition during lactation. Improvements in efficiency could occur as a result of changes in digestion and nutrient absorption, maintenance requirement, utilization of metabolizable energy for production or nutrient partitioning. Digestibility can be greatly enhanced by appropriate dietary manipulation. Likewise, it may be possible to reduce maintenance requirements and improve the efficiency with which metabolizable energy is used for milk synthesis by manipulation of the pattern of nutrients presented to tissues. However, these factors apparently do not respond to selection for increased milk yield, and little variation is observed among cows. In contrast, individual cows differ substantially in feed intake and in the partitioning of nutrients among body tissues. Techniques associated with genetic engineering and the early prediction of genetic merit have the potential to improve productive efficiency by manipulation of these processes. However, changes in nutrient partitioning and feed intake during lactation are coordinated by a complex network of controls that accommodate the nutrient requirements of each tissue while maintaining homeostatic balance. Future improvements in productive efficiency will therefore depend on our ability to understand the manner in which these controls operate. 相似文献
120.
1. Automatic weighing equipment was tested on a flock of 752 roaster chickens reared on litter to 10 weeks of age.
2. Mean body weights obtained automatically were lower than those obtained manually, mainly because of birds perching on the automatic weighing perch with part of their body in contact with the floor.
3. Birds observed on the weighing perch on one day of the week were 3–5 times more likely to use the perch again on the following 2 d than expected on the basis of random perch use by flock members. These birds were also more likely to be seen in the area immediately surrounding the perch than in similar areas elsewhere in the pen. 相似文献