# Physicochemical Properties and Oxidation Status of Pork from Three Rearing Systems
## 2 Materials and Methods  
### Rearing Conditions of Animals and Sample Preparation  
Samples of meat were obtained directly from breeders at their slaughterhouses. The samples of organic pork were from Biofarma Sasov (Sasov 2, 58601 Jihlava, Czech Republic), conventional pork from slaughterhouse Sebkovice, s.r.o. (Sebkovice, 675 45, Czech Republic) and traditional pork were from Farma roolny Nemcovy (Netin 78, 594 44 Radostin nad Oslavou, Czech Republic). Information about the age and weight of pigs at slaughter as well as the genotypes of pigs is shown in Table 1. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Rearing** & **Age (months)** & **Live Weight (kg)** & **Genotype** \\ \hline Organic & 7 & 80 & Prestice Black-Pied (meat/bacon breed) \\ Conventional & 6 & 110–120 & Czech Improved White (meat type) \\ Traditional & 7 & 90–100 & Prestice Black-Pied \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Characteristics of pigs from organic, conventional and traditional rearing systems. Organic pig farming: after birth, piglets stayed with their mothers till 35 days of age, then with their mothers were moved to the stables. In these stables, there are usually 5 to 6 sows with piglets and always 1 boar. Piglets were fed sow milk that provides them nutrition and protection against diseases. The animals had constant access to the outdoors to encourage natural life processes as in nature. Weaning occurred at 3 months of age of the piglets. After weaning, the piglets remained in the same environment, in the same stable as before. The period of feeding was 7 months. Feed rations were balanced, full-value, composed exclusively of organic feed and the permitted amount of permitted conventional feed--no extracted meal, no meat-and-bone meal, growth promoters, hormonal substances, synthetic amino acids, antibiotics, etc. Ecological slaughter was ensured by slaughterhouses directly on the farm. During all movements within the farm, the pigs walk on their own and are not stressed by transport, including the journey to the slaughterhouse. The entire breeding process of livestock on the farm is based on the greatest possible animal welfare and their most natural living conditions. Conventional pig farming: after birth, piglets stay with their mothers for the first 3 weeks of their lives. Consequently, the weaning was conducted at the earliest at 3 weeks of age. Then, animals were divided into groups according to sex and breeding plan immediately after weaning. Pigs were in permanently closed stables with controlled air conditioning. Animals were grown (for 6 months of their life) in the region of Vysocina, Sebkovice, the Czech Republic. The conditions in the housing were the following: minimum pen area for one animal according to the weight: up to 50 kg = 0.40 m\({}^{2}\); up to 85 kg = 0.55 m\({}^{2}\); up to 110 kg = 0.70 m\({}^{2}\). Traditional pig farming: the farm is located in the Vysocina region (village of Netin). The farm operates on 150 hectares of agricultural land and owns approx. 70 pigs of the Prestice Black-Pied breed. The farm combines modern technology with rural experience and skills. The Prestice Black-Pied genotype is the original Czech breed [19] and is appropriate for use on small farms and organic system production. This genotype is not suitable for conventional systems and on large farms. The growth period was extended to 7 months; pigs received a tailor-made feed ration without use of GMO feed. Sample preparation: a total of 30 samples (out of 30 individual barrows) from three different rearing systems were used for analysis. Ten meat samples of about 150 g from _M. biceps femoris_ were taken from each farm. The meat samples were transported in a cold atmosphere (around 4 \({}^{\circ}\)C) to the University of Veterinary Sciences Brno where the analyses were conducted. Physicochemical and oxidative analysis was performed 3 days after slaughtering.