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991.
Magnetic resonance imaging (MRI) data were correlated with clinical and cerebrospinal fluid (CSF) findings in one cat and two dogs with brain lesions. In all three cases, localization of the lesions, as determined clinically, was confirmed using MRI. Magnetic resonance imaging also helped us to define the full extent of the lesion(s) in each case. In one case, the lesion would have been diagnosed as purely inflammatory based on the abnormalities in the CSF. The MRI study, however, showed a homogeneous mass with circumferential changes characteristic of peritumoral edema or inflammation. In two cases, the MRI findings were confirmed at necropsy. An MRI study was also done on a normal dog, demonstrating the variable contrast and anatomical detail possible using this technique. We also discuss difficulties in identifying tumor type using MRI.  相似文献   
992.
993.
Morbidity (greater than or equal to 1 disease condition) for pups sold from 3 pet stores from January 1987 through December 1988 ranged from 54 to 68%. In 1 store, morbidity was higher for store pups, compared with pups originating from private parties, for such disease conditions as "kennel cough," diarrhea, and several species of gastrointestinal parasites. In-store mortality ranged from 5 to 9.5% of pups arriving for sale.  相似文献   
994.
1. An experiment was conducted with laying hens to determine to what extent sweet white lupins (Lupinus albus, cv Buttercup) could be used as a protein source in their diets.

2. Twenty five individually caged 20 week‐old Hisex laying hens were used per treatment. The hens were housed in a convection house for the duration of the study which lasted 52 weeks. Two diets were formulated, one containing 300 g sweet lupins/kg and the other containing sunflower oil cake and fish meal as protein sources. These diets were blended to obtain seven diets with lupin inclusion rates of 0, 50, 100, 150, 200, 250 and 300 g/k.

3. Results indicated that up to 300 g lupins/kg diet can be fed to Hisex laying hens without a significant effect on egg production, egg mass, efficiency of food utilisation, egg shell thickness, Haugh units or yolk colour. Food intake was however, significantly (P<0.05) positively correlated with lupin inclusion rates.  相似文献   

995.
996.
From the first discovery of bluetongue virus activity in Canada in the Okanagan Valley of British Columbia in 1976 to the present, more than 175,000 sera from cattle in Canada have been tested for the presence of bluetongue antibody during the course of disease investigations and during regional or national surveys. Serological reactors have been detected only in cattle resident in the Okanagan Valley or in those originating in the United States.

Despite the regional nature of the distribution of antibody to bluetongue, international trade sanctions were applied on a nationwide basis. The strategy of the federal government for limiting the international, as well as the domestic, impact of bluetongue has evolved over the past 15 years as the epizootiology of bluetongue has become better understood. This new information is also ameliorating somewhat international attitudes toward nations which experience infections.

  相似文献   
997.
998.
999.
The right and left lungs of 5 healthy Minipigs and of 13 healthy Landrace piglets were isolated, perfused at constant pressure and maintained in an isogravimetric state under zone III conditions (pulmonary venous pressure>alveolar pressure). By applying the double, arterial and venous, occlusion technique, the total blood flow resistance (R t) was partitioned into four components: arterial (R a), pre-(R a) and post-capillary (R v) and venous (R v). The capillary filtration coefficient (K f,c) was evaluated by measuring the weight gained by the lungs when the arterial and venous pressures were suddenly increased. In the youngest Landrace piglets (5 weeks old), there was an uncontrolled vasoconstriction which sometimes prevented perfusion of the lungs and induced a large increase inR t. These high values ofR t were decreased by tolazoline administration. The values ofR t recorded in older pigs (12–13 weeks old) were lower in Minipigs (33.66±3.77 cmH2O min L–1 per 100 g of lungs;n=5) than in Landrace piglets (55.20±6.18 cmH2O min L–1 per 100 g;n=5). This breed difference was due to the differences inR a andR v. The mean values ofK f,c were 0.193±0.015 and 0.202±0.029 ml min (cmH2O)–1 per 100 g of the lungs in Minipigs and Landrace piglets respectively. All these parameters were stable for the 3 hours following the equilibrium period. It was concluded that: (1) There is an age-related maturation of the control of the vasomotor tone in porcine lungs. (2) Pulmonary microvascular haemodynamics are influenced by the breed of the pigs. (3) There was no difference in theK f,c values between both the breeds. (4) A comparison of the values reported for dogs and rabbits with our data shows that the pre- and post-capillary resistances and, to a lesser extent, the arterial and venous resistances are relatively high in pigs.  相似文献   
1000.
Twelve veterinarians were asked to estimate the percentage of lung surface that appeared consolidated in eleven projected colour transparencies of pneumonic ovine lungs. The estimates were compared to the pneumonic area measured by image analysis. Although all observers had some experience in veterinary pathology there was considerable variation between individuals in the accuracy of their estimates. Large lesions were underestimated and small lesions overestimated by most observers.  相似文献   
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