## 4 Discussion
### Marbling Scores  
The marbling scores assessed by VIA at both rib positions in this investigation were slightly higher than marbling scores of young bull carcasses that were assessed at the 10 th rib position using the Australian MSA grading scheme with trained graders [12]. The comparison of the results with other assessed marbling scores is difficult as there are only a few studies about VIA-assessed marbling scores of young bull carcasses. carcasses from bulls are mostly classified using EUROP traits or intramuscular fat content. Although VIA marbling scores and the analysis of intramuscular fat content reached high correlations [20; 21], visual marbling and intramuscular fat content describe different carcass traits. [PERSON] et al. [24] investigated very low mean values for the amount of intramuscular fat content at the 8 th rib section of _longissimus thoracis_ for double-muscled bulls (0.9%) and higher mean values for non-double-muscled bulls of different Belgian breeds (3.0%) that had higher carcass weights (413 kg) than in the current study. [PERSON] et al. [25] found low intramuscular fat contents (2.5%) of German Charolais crossbreeds and German Holstein bulls. In contrast to a recent study [18], the assessed marbling scores were slightly higher at the 12 th/13 th rib-eye section. In the same recent investigation [18], carcasses of young German heifers of different breeds reached slightly lower marbling scores than in the current study assessed with VBG 2000 at the 10 th/11 th rib-eye position of _longissimus thoracis_. However, the authors emphasized the low quality of the German carcasses in comparison to carcasses used in US studies with larger samples [18]. Based on the large number of studies which emphasize that heifers and steers tend to show higher marbling scores than bulls [26], these differences may be explained by the very low quality of the assessed carcasses from these particular heifers.  
The variation of marbling scores (385 to 942 marbling points) obtained in the current study was higher than that found in other studies [18]. This is mainly due to the targeted heterogeneity of the carcass samples to include beef and dairy cattle of different age and slaughter weight, and deriving from different farms and genotypes. Although the carcasses were heterogeneous, they were all produced for the German beef market and reflect high inconsistency in beef quality. Thus, the need for viable tools to standardly assess and classify the different marbling levels of German carcasses is obvious.  
EUROP fat classes showed only weak correlations with the marbling scores at both positions. In accordance with this, a study done by [PERSON] et al. [3] indicated that EUROP fat classes were not useful for predicting sensory eating quality traits. In contrast, [PERSON] and [PERSON] [18] found higher correlations between visually assessed EUROP fat classes and VIA-assessed marbling scores of carcasses from heifers at the 10 th/11 th rib position (r = 0.40) and the US position (r = 0.36). [PERSON] et al. [16] determined slightly lower correlations (r = 0.30) between EUROP fat class and MSA marbling scores of male and female beef and dairy breed carcasses at the 12 th/13 th rib-eye section. In the current study, EUROP trade grades showed even higher correlations with marbling scores than with EUROP fat classes. Since the relationships between the degree of marbling and the amount of fat of the whole carcass have been discussed at length [27], weak relations between EUROP fat class and marbling were expected. However, the precision of EUROP fat classes is not sufficiently guaranteed. The current results support the conclusions made by others [1; 3; 8; 12; 16] that EUROP traits are not suitable for classifying beef quality attributes and need to be modified.