Breed‐specific variation of hematologic and biochemical analytes in healthy adult Bernese Mountain dogs

Background: Hematology and serum biochemistry reference intervals in dogs may be affected by internal factors, such as breed and age, and external factors, such as the environment, diet, and lifestyle. In humans, it is well established that geographic origin and age may have an impact on reference intervals and, therefore, more specific reference intervals are sought for subpopulations. Objective: The objective of this study was to validate and transfer standard laboratory reference intervals for healthy Bernese Mountain dogs and to create new intervals for analytes where the established laboratory reference intervals were rejected. Methods: The procedure was performed using the human Clinical and Laboratory Standards Institute‐approved model modified for veterinary use. Thirty‐two dogs were included in the study using a direct a priori method, as recommended. Results: While 23 of the standard laboratory reference intervals were readily validated, 7 of the analytes (eosinophils, MCHC, alkaline phosphatase [ALP], γ‐glutamyltransferase, total bilirubin, amylase, and cholesterol) required new reference intervals according to the standard. These were calculated using the robust method. In particular, the new reference range for ALP was wide compared with the established laboratory reference interval. No clinical causes were found for differences in the results of these analytes. Conclusion: We found significant differences in 7 hematologic and serum biochemical analytes for which a breed‐specific variation appears to be the most plausible explanation. Breed‐specific reference intervals for Bernese Mountain dogs will help avoid misinterpretation of laboratory results in the diagnostic process.     

Role of predominant rumen bacteria in the cause of polioencephalomalacia (cerebrocortical necrosis) in cattle

Rumen contents of 2 heifers with acute polioencephalomalacia (cerebrocortical necrosis) were compared with rumen contents from a healthy steer fed a fibrous diet. Also examined were (i) the quantitative nature of the predominant rumen microflora, (ii) the distribution of morphologic types of bacteria in the rumen contents, (iii) the extent that morphologic groups produced or degraded thiamine, and (iv) the cumulative effects of metabolic activities of the predominant rumen bacteria concerning the net production or degradation of thiamine. The differences in the frequency of occurrence of particular bacterial morphologic groups, the extent of growth, and the amount of thiamine metabolism in relationship to growth were also evaluated. The cumulative thiamine metabolism of the predominant bacteria associated with the rumen of polioencephalomalacia-affected heifers led to substantial net thiamine destruction, whereas metabolism associated with the rumen of a normal steer led to thiamine production. Polioencephalomalacia may occur as a consequence of alteration of the metabolic activities of the predominant resident ruminal bacteria associated with diseased cattle.     

Muscular cysticercosis from Taenia ovis in feedlot lambs.

From a Colorado enterprise annually fattening about 50,000 lambs, 3,664 animals were examined for muscular cysticercosis. Of the total number, 406 (11.1%) were parasitized, wheras an estimated 0.1% of Colorado lamb carcasses are infected. Of the infected lambs, 60% had cardiac lesions. Two types of cysticerci-viable and degenerated-were found. The lambs probably acquired infection from grazing summer ranges and pastures where coyotes or dogs infected with Taenia ovis contaminated the forage.     

Pathology of liver granulomas in turkeys

Liver granulomas from five- and seven-week-old turkeys were studied by light and electron microscopy and by bacterial culture. Granulomas of five-week-old poults were composed of a caseous, necrotic center surrounded by consecutive zones of heterophils, giant cells, macrophages, and finally by lymphocytes. Tissue Gram and modified Dieterle stains demonstrated numerous gram-positive, filamentous bacteria in necrotic centers with radial extension of the bacteria to the zone of giant cells. Electron microscopic examination revealed septate, filamentous bacteria within an electron-dense milieu between heterophils, macrophages, and giant cells. An anaerobic, gram-positive bacillus and a staphylococcus were isolated from most granulomas examined. In broth, the bacillus formed long filaments or chains morphologically similar to those in tissue sections. The bacillus was identified tentatively as Eubacterium tortuosum. The staphylococcus had cultural reactions typical for Staphylococcus epidermidis. Intravenous inoculation of three-week-old poults with a mixture of E. tortuosum and S. epidermidis produced granulomas in liver and spleen and multiple mucosal ulcers in the duodenum and colon.     

The microflora and concentrations of volatile fatty acids in the rumen of cattle fed on single component rations

The composition of the rumen microflora and the volatile fatty acids were examined in cattle free-grazing on grass or stall-fed on hay, grass pellets, oats or dried beet pulp with molasses. Total and viable counts of anaerobic bacteria were highest on the grass feeding, but viable counts as a percentage of total counts were highest when oats or beet pulp with molasses were fed. Counts of cellulolytic bacteria were lowest on these latter 2 diets, and highest on grass or grass pellet diets. Studies of the anaerobic flora showed that the composition in animals fed on grass pellets resembled more that found in animals free-grazing on grass than in those fed on hay. Counts of aerotolerant bacteria were only a small percentage of the total count, but were highest on the hay diet. On this latter diet and on grass-feeding the streptococci (identified as Streptococcus bovis) were predominant, but contrary to expectation, streptococci were found only in small numbers on the oats diet, where coryneform rods were the major type present. Although a period of 4–6 weeks was allowed for the animals to adapt to the feeds, the 2 periods of feeding on oats and dried beet pulp with molasses markedly affected the composition of the rumen flora in the subsequent periods of feeding grass pellets and hay. Ruinen volatile fatty acid analysis showed a propionogenic effect of oats and the highest percentage of butyric acid when beet pulp with molasses was fed. The expected propionogenic effect of grass pellets was not observed.