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Abstract: Although it has been demonstrated that European roe deer (Capreolus capreolus (L. 1758)) may migrate seasonally in areas with snow gradients, this behaviour remains scarcely understood. From 1999 to [...]

The aims of this study were 1) to apply computer image analysis to obtain measures of lean and fatty areas on the cross section of dry-cured hams, 2) to investigate variation of these measures, and 3) to evaluate reproducibility and repeatability of these techniques. Traits of concern were the cross-sectional area (SA), lean, or muscles, area (LA), and the fatty area (FA) centered on the cross section and surrounded by biceps femoris, semimembranosus, semitendinosus, and quadriceps femoris, as well as the FA-to-SA ratio (FESR). Hams were obtained from crossbred pigs (n = 279) slaughtered at 9 mo of age (mean BW of 169 [+ or -] 17 kg). Digital images of the cross section of dry-cured hams were captured using standardized procedures. Three replicated measures of areas were collected by three operators using three image analysis techniques (automatic, automatic-assisted, and manual). Variance components were estimated using a linear model that included slaughter group, gender, and gender x slaughter group as fixed effects and operators, pig, and operator x pig as random effects. Statistical analyses considered all measures (n = 7,533) or measures collected after reinstruction of all operators for spatial calibration of the analysis system (n = 4,428). Average SA, LA, FA, and FESR were 350 [cm.sup.2], 220 [cm.sup.2], 8.7 [cm.sup.2], and 2.5%, respectively. Variability of FA (CV = 42%) and of FESR (CV = 39%) was four times greater than that of SA and LA. Slaughter group, pig, operator, and operator x pig effects were the most (P < 0.01) important sources of variation of measures. Correlations between measures obtained with different techniques were greater (P < 0.01) than 0.90, with the exception of LA measures. Coefficients of reproducibility for SA and LA ranged from 87 to 94%, whereas those for FA and FESR ranged from 88 to 98%. Coefficients of repeatability ranged from 92 to 99%. Automatic-assisted and manual methods provided more reproducible and repeatable measures than the automatic technique. Spatial calibration of the software system was a key issue affecting reproducibility and repeatability. Reinstructing the analysts for spatial calibration enhanced both reproducibility and repeatability of all methods of analysis. Computer image analysis is a technique suitable for measuring lean and fatty areas in cross-sectioned hams, providing reproducible and repeatable measures, and it might be used in large sample-based studies to investigate causes of defective fatty areas. Key Words: Computer Image Analysis, Fat, Ham, Pigs, Repeatability, Reproducibility

The aim of this study was to assess the prevalence of spondylosis deformans and to investigate genetic aspects of the degree of osteophytes development (DOD) in the Italian Boxer dog population. A total of 849 Boxer dogs was radiographed on the thoracic, lumbar, and sacral regions of the spine and scored for DOD. Grading of DOD was performed for all 20 intervertebral sites comprised within the first thoracic site (site T1-T2) and the site between the seventh lumbar and the first sacral vertebra (site L7-S1). Scores for DOD ranged from 0 (no osteophytes development) to 3 (presence of a bony spur formed by osteophytes on adjoining vertebrae). The first five thoracic sites exhibited no variation for DOD and were not considered in the analysis. The prevalence of spondylosis deformans was 84%, and frequency of dogs showing at least one intervertebral site that scored 3 for DOD was 50%. Scores for DOD at different sites were analyzed as different traits. Nongenetic effects influencing DOD scores were sex, age at screening, and the kennel. Posterior densities of heritability ([h.sup.2]) were estimated using a univariate Bayesian analysis. Eight sites exhibited a posterior probability greater than 0.8 for [h.sup.2] > 10% and were considered in a multivariate restricted maximum likelihood analysis. Estimated [h.sup.2] from multivariate analysis ranged from 25 to 48% (SE from 5 to 7%). Three sites exhibited [h.sup.2] estimates greater than 40%. Genetic correlations for DOD scored at different sites ranged from 0.07 to 0.96. All thoracic sites had estimated correlations larger than 0.85 with other thoracic sites. Genetic correlation between the first and the second lumbar site was 0.91. Correlations between thoracic sites and the first two lumbar sites ranged from 0.5 to 0.9. Sites L6-L7 and L7-S1 also exhibited weak relationships with all remaining sites. Breeding values of dogs for DOD at the eight sites were predicted using estimated covariance matrices. A selection index for DOD was computed from predicted breeding values and a set of relative weighting factors produced by a panel of veterinarians. The index was the most important effect influencing phenotypic differences between dogs for average DOD score, number of affected sites, and number of sites with a DOD score > 1 (P < 0.001). The degree of osteophytes development is a trait showing exploitable additive genetic variance, and breeding programs for decreasing prevalence and severity of spondylosis deformans might focus on this trait. Key Words: Boxer, Dog, Genetic Correlations, Heritability, Osteophytes Development, Spondylosis Deformans