Predicting Beef Carcass Fatness Using an Image Analysis System

Image analysis traits of multiple muscles and intermuscular/subcutaneous fat influence Japanese Black beef carcass price and genetic parameters

OBJECTIVE

The purposes of this study were to investigate the relationship between carcass unit price per 1 kg (UP) and multiple muscles and intermuscular fat (IF)/subcutaneous fat of beef carcasses using image analysis of cross-section images for Wagyu beef cattle in Japan, and to estimate their genetic parameters.

METHODS

The carcasses used in this study were 1,807 Japanese Black (Wagyu) cattle (1,216 steers and 591 heifers). An analysis of variance was conducted with UP as the dependent variable and market date, age in months, sex, and image analysis traits (IAT) as fixed effects, and standard partial regression coefficients were calculated for each IAT on UP. Also, the heritability of each IAT that affected UP and genetic correlation among IAT vs carcass grading traits were estimated.

RESULTS

Not only IAT related to carcass grading traits, M. trapezius dorsi, M. latissimus dorsi, and IF traits were significant differences in UP (p<0.05). The heritability of IAT associated with UP was estimated at 0.38 to 0.85. The genetic correlations between the area and thickness of M. trapezius dorsi and M. latissimus dorsi vs rib eye area (REA) were estimated to be moderately positive (0.53 to 0.66), while the genetic correlations between the IF area percentage vs carcass weight, REA, and yield score were estimated to be negative (-0.40, -0.56, and -0.34).

CONCLUSION

UP was influenced by various traits, including M. trapezius dorsi, M. latissimus dorsi, and IF traits, as well as image analysis associated with carcass grading traits. Since these IAT associated with UP had hereditary and desirable genetic correlations with carcass grading traits, these traits were also important for genetic improvement.

Using in-abattoir 3-dimensional measurements from images of beef carcasses for the prediction of EUROP classification grade and carcass weight

Imaging technology can aid the automatic extraction of measurements from beef carcasses, which can be used for objective grading. Many abattoirs, however, rely on manual grading due to the required infrastructure and cost, making technology unfeasible. This study explores 3-dimensional (3D) imaging technology, requiring limited infrastructure, and its ability to predict carcass weight, conformation class and fat class for non-invasive, objective classification. Time-of-flight near-infrared cameras captured 3-dimensional point clouds of beef carcasses, on-line in one commercial abattoir in Scotland, over a 6-month period. Thirty-five 3D images were captured per carcass and processed using machine vison software. Seventy-four measurements were extracted from each point cloud. Removal of extreme outliers resulted in 285,109 datapoints for 17,250 carcasses. Coefficients of variation (CV) for each measurement on a per-animal basis were low and consistent, and measurements were averaged across images. Using a training and validation dataset (70:30), multiple linear regression models predicted EUROP conformation class, fat class, and carcass weight. Stepwise models included fixed effects (sex, breed type, kill date (and cold carcass weight for conformation and fat class)), and 3D image measurements. Including 3D measurements resulted in prediction accuracies of 70%, 50% and 23% for cold carcass weight, conformation, and fat class respectively. Mapping predictions on the traditional EUROP grid used in the UK showed that 99% of conformation classes and 93% of fat classes were classified within the correct or neighbouring grade. The results of this study indicate the potential for non-invasive, in-abattoir technology requiring limited infrastructure to predict carcass traits objectively.

A New Insight on Carcass and Meat Quality in Ruminants

Ruminant production systems are very important in many areas of the world and a key aspect of the economy and culture [...].

The influence of the rotational speed of the meat cutter knives and bowl on the microstructure of meat products

The aim of the study was to determine the structure of meat batter and processed meat products, depending on the chopping time and rotational speed of the cutter knives and bowl, by means of histochemical methods combined with the computer image analysis system. Finely comminuted meat batters and processed meat products were investigated. Four variants of the rotational speed of cutter knives and bowl were applied in the experiment: 1500/10 rpm, 1500/20 rpm , 3000/10 rpm and 3000/20 rpm. The chopping process lasted 10 min. After 5, 6, 8 and 10 min of chopping samples of meat batter and processed meat products were collected for histological analyses. The microstructure of structural elements (fat globules and collagen fibres) was measured using computer image analysis. The following parameters were included in a characteristic of the images: the area, circumference, length and width of fat fields; the number of fat fields analysed; the percentage of fat fields in the field under analysis; the area, circumference, length and width of collagen fibres. The computer image analysis showed that the optimal speed of the cutter knives and bowl was 3000/20 rpm. The chopping time was reduced from 10 to 8 min.