The effect of dietary halloysite supplementation on the performance and meat quality of pigs and some air indices in piggery.

Halloysite, a clay mineral of the kaolin, has specific properties, characteristic for the conditions in which it was formed. The aim of the study was to determine the effect of halloysite from the Dunino deposit in a complete diet for pigs on daily body weight gain (BWG), feed conversion ratio (FCR), blood parameters, chemical composition of meat and chosen environment indices in the piggery. The trial was conducted on 144 piglets from weaning (d 29) to 85th day of life, then on 40 porkers divided into two groups. Animals were fed diets without (group C) or with halloysite (group E; 1.5% until d 128, then 1.0%). Pigs from group E were characterized by a lower number of days with diarrhea. The average BWG in E group was 44 g higher than in group C (P < 0.01). In turn, during the fattening period, the difference in BWG between groups was 60 g in favor of E (P < 0.05) and average FCR in group E was 4.9% lower compared to group C (P < 0.05). At the end of the study, the pigs from group E had 6.9% higher final body weight (P < 0.01). During both the morning and evening measurements, ammonia concentration in the air was lower by 16.3% and 23.8%, respectively. The use of halloysite enabled improvement of pig fattening efficiency, while reducing the costs of pork production and the negative effect of ammonia on the animals' welfare and environment.