Assessment of the possibility of replacing imported protein sources with alternative domestic protein feeds in the feeding of fattener pigs in terms of their fattening, slaughter and economic value

The aim of the research is to evaluate the replacement of post-extraction soybean meal with high-protein plants grown in Poland in the diet of fattener pigs in terms of their fattening and slaughter value as well as production profitability. Peas, faba beans, sunflower meal and hemp and linseed cake were the main source of protein in the experimental group. The experiment was carried out on 60 fatteners of the Puławska breed and lasted 119 days, and the average age at slaughter for both groups was 184.90 days. The body weight on the day of slaughter ranged from 105 to 128 kg (control group) and 105 to 124 kg (experimental group). The study included an assessment of: fattening value, slaughter value (including detailed dissection of the 5 most valuable cuts) and the economic and commercial value of the carcass. Based on the analysis of the results, a positive effect of substituting protein from post-extraction soybean meal with a mixture of domestic protein components was demonstrated. Although the experimental group was characterised by lower daily gains, higher feed intake, and thus a less favourable feed conversion ratio, the cost of feeding these fattening pigs was significantly lower. It was also found that the carcasses of the fattened pigs in the experimental group had statistically significantly lower backfat thickness and higher loin ‘eye’ height and carcass leanness, which in turn resulted in higher weight of valuable cuts. There was no effect of the feeding modifications on the economic and commercial value of the carcass, however it was shown that feeding fattener pigs with a mixture of domestic protein components in the experimental group increased the profit from their production.