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81.
82.
Six shipments totaling 3452 mummies of the blackmargined aphid,Monellia caryella (Fitch), parasitized withAphelinus perpallidus Gahan, were obtained by air freight during the years 1982-1985 from Texas A&M Research Center, El Paso, Texas. About two-thirds of the mummies did not yield parasites. A colony ofA. perpallidus was established in the laboratory. Under laboratory conditions the percentage of emerged parasites was higher than that in the imported mummies, and the parasite had very limited impact on the aphid population. Field releases of the parasite were made but no establishment ofA. perpallidus was observed through the years. 相似文献
83.
Adetunji A Pascoe PJ McDonell WN Horney FD 《The Canadian veterinary journal. La revue veterinaire canadienne》1984,25(9):342-346
A retrospective morbidity and mortality study was carried out on 125 case records of cattle involving xylazine/halothane anesthesia at the Ontario Veterinary College, Guelph between May 1979 and February 1983. 相似文献
84.
Specificities of antinuclear antibodies detected in dogs with systemic lupus erythematosus 总被引:4,自引:0,他引:4
O Costa C Fournel E Lotchouang J C Monier M Fontaine 《Veterinary immunology and immunopathology》1984,7(3-4):369-382
Five hundred and eighty dogs with at least one clinical sign compatible with a systemic lupus erythematosus (SLE) were entered in a prospective study aimed at evaluating the prevalence of antinuclear antibodies (ANAb). SLE was diagnosed in 38 of these dogs (group A) which fulfilled at least four American Rheumatism Association (ARA) criteria; of these, sixteen had ANAb titers greater than or equal to 4096. The 23 dogs which met three or two ARA criteria (group B) had an ANAb geometric mean titer (GMT) of 259. Dogs (group C) with only 1 criterium had an ANAb GMT of 75. Anti-ds-DNA Ab were present in 6 dogs from group A (16%), and 2 dogs from group B (9%). Anti-histone Ab were present among dogs from group A, B and C with frequencies of 81%, 67% and 26%, respectively. Among dogs from group A, the ANAb titers and the levels of anti-histone Ab correlated positively when individual sera were considered. Antibodies against the soluble nuclear antigen (SNA) were detected in 74%, 39% and 13% of the dogs from groups A, B and C, respectively. Antibodies initially described in human SLE also exist in SLE dogs. Anti-Sm Ab were found in 24% of dogs in group A. With anti-RNP Ab the frequency was still lower (10%). However, two other types of anti-SNA Ab against RNAse and trypsin-resistant antigens, not found in human "reference sera", were often detected. The first type (anti-type 1 Ab) was found in 26% and 9% of group A and group B, The first type (anti-type 1 Ab) was found in 26% and 9% of group A and group B, respectively; the second type (anti-type 2 Ab) is less frequent, and was found in 13% and 17% of group A and B, respectively. It appears that testing for anti-Sm, anti-type 1 and anti-histone Ab should be performed in order to improve the diagnosis of SLE in dogs. 相似文献
85.
86.
Perera FP 《Science (New York, N.Y.)》1986,234(4774):372-373
87.
88.
89.
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
90.
Examination of the origin of increased equine serum alkaline phosphatase concentrations 总被引:2,自引:0,他引:2
Trueman KF Lumsden JH McSherry BJ 《The Canadian veterinary journal. La revue veterinaire canadienne》1983,24(4):108-111
Serum alkaline phosphatase activity was found to be increased in 32.6% of equine samples analyzed at the Ontario Veterinary College over an 18 month period. An attempt was made using sensitivity to L-phenylalanine and heat to identify the origin of increased serum alkaline phosphatase isoenzymes present in 44 clinical cases. No difference in sensitivity to either procedure was observed for serum alkaline phosphatase from groups of foals and horses representing different clinical problems. Alkaline phosphatase of osseous tissue origin appeared to be the major source of activity for each group of animals reported. 相似文献