A COMPARISON OF RADIOGRAPHIC AND COMPUTED TOMOGRAPHIC FINDINGS IN 31 DOGS WITH MALIGNANT NASAL CAVITY TUMORS

Nasal cavity radiographs and CT images from 31 dogs with nasal cavity cancer were compared. All dogs had abnormal clinical signs relating to -nasal cancer and histologic confirmation of malignant nasal cavity neoplasia. No dog had cyto reductive surgery prior to imaging. All radiographic and CT examinations were abnormal. CT was more accurate than radiographs in identifying unilateral versus bilateral nasal cavity disease and tumor extension into adjacent structures such as the cranial cavity, hard palate, and pterygopala-tine fossa. The improved accuracy of CT in these respects was not of benefit in the confirmation of nasal cavity disease because radiographs were abnormal in every instance. However, CT may be useful for more accurate tumor staging, predicting possible treatment-related complications, and planning of surgery and radiation therapy. It was also determined that one dorsally located radiation therapy portal bounded laterally by the medial ocular canthi, as described in previous reports, would not have been adequate for encompassing all abnormal tissue in 28 of the 31 dogs evaluated.     

Antibody response to experimental Salmonella typhimurium infection in chickens measured by ELISA

An indirect ELISA has been developed to detect Salmonella typhimurium antibodies in chicken sera, using whole bacterial cell protein, flagellar protein or lipopolysaccharide as antigens. In experimental infections high concentrations of S typhimurium-specific IgG persisted after the faecal excretion of S typhimurium had ceased, whereas the specific IgM response was transitory. Some uninfected chickens placed in contact with experimentally infected birds developed high IgG titres in the absence of detectable faecal excretion. Other S typhimurium strains, which varied in their invasive abilities, also induced high titres of IgG. The ELISA allowed chickens infected experimentally with S typhimurium to be differentiated from chickens infected with 10 other serotypes, including S enteritidis. The use of whole blood in place of serum in the ELISA reduced the titres slightly. The storage of serum dried on to filter paper strips for four weeks produced little change in ELISA antibody titre, and the treatment of such strips with phenol or chloroform vapour had little or no effect on the antibody titre.     

Property Rights and Public Interests: A Wyoming Agricultural Lands Study

Rocky Mountain states have experienced unprecedented growth as agricultural land is converted to residences. Preservation efforts meet with protest from private landholders claiming public efforts undermine private property rights. This paper explores the degree to which respondents think management of agricultural lands is a public versus a private matter. Data are from a Sublette County, Wyoming, mail survey. Results are relevant to many western counties having public lands and high growth rates. They suggest that landowners, wage earners, college graduates, and those who value the county’s rural community lifestyle support public management strategies. Well‐established residents and those with economic reasons for living in the county support private management strategies.     

PREDICTING ORGANIC-MATTER DIGESTIBILITY FROM IN VIVO AND IN VITRO DETERMINATIONS OF DRY-MATTER DIGESTIBILITY

The DM digestibility (DMD) and organic matter digestibility (OMD) of 36 tropical grass samples were determined both in vivo and in vitro. Regressions relating OMD to DMD were calculated. In vivo OMD=1·02 in vivo DMD+ 0·1, r=0·99. In vitro OMD=1·05 in vitro DMD—4·7, r=0.99. At the same DMD, the in vitro method predicted OMD 2·8 to 3·4 percentage units lower than the in vivo method. This difference was caused by the difference in mean apparent digestibility of the ash, in vitro 71%, in vivo 47%. In vivo DMD was correlated (r=0·92, P<0·01) with in vitro DMD and the regression relating these two factors had a residual standard deviation of ±1·42 digestibility units. This deviation was reduced to ±1·9 digestibility units when OMD was determined. For both DMD and OMD significant differences were found between grass species in the relation between in vivo and in vitro digestibility. To overcome biased estimates of OMD it was suggested that conversion equations should be avoided, and that the in vitro method be standardized with samples of known in vivo OMD as similar as possible to those being tested.     

Spatial patterns of recreational exploitation in eastern Australian ROFAs: implications for zonal management

Effective management of recreational fisheries requires information on fine‐scale spatial patterns of recreational exploitation. Such information is particularly important for specially designated regions such as recreational‐only fishing areas (ROFAs). Using data acquired through progressive counts and interview‐based surveys, this study quantitatively compared recreational effort, harvest‐per‐unit‐effort (HPUE) and species composition among zonal habitats in three representative estuarine ROFAs in eastern Australia. The zones compared were as follows: (1) entrance channels; (2) lake areas; (3) artificial reefs; (4) tributary creeks; (5) rivers; and (6) canals. In most cases, effort was concentrated in the lake zones, which had the greatest access to fisheries resources. The lake and channel zones were associated with some of the highest HPUEs for key taxa [Acanthopagrus spp. (hybrid complex of Acanthopagrus butcheri (Munro) × Acanthopagrus australis (Owen)), Platycephalus fuscus (Cuvier), Sillago ciliata (Cuvier) and Girella tricuspidata (Quoy & Gaimard)] and a greater number of highly sought‐after species. Drawing on specific examples from these findings, this paper concludes by illustrating how spatial information on exploitation gained from this type of research can be used to meet the fundamental goals of recreational fisheries management at fine spatial scales.