The present trial verified the effects of spraying microbial agents on odor reduction in commercial pig farms of different operating sizes and barn types. Farms without microbial agent spraying and those sprayed with microbial agents at two different intervals were compared. The treatments included spraying of water alone every day or a mixture of water plus microbial agent at 24 and 72 h intervals. The experimental farms were divided according to size into 1,000-, 3,000-, and 5,000-head farms and according to barn type into gestation, farrowing, nursery, and grower-finisher farms. To compare odor concentration within each housing barn, ammonia and hydrogen sulfide gas levels were measured. The average concentrations of ammonia (p<0.01) and hydrogen sulfide (p<0.05) gas were the lowest in all types of farms sprayed with the microbial agent at a 24 h interval. In farms sprayed with the microbial agent at a 24 h interval, the decrease in ammonia concentration according to barn type was in the following order: farrowing (p<0.01) (11.0 to 1.8 ppm), nursery (p<0.05) (17.0 to 9.2 ppm), grower-finisher (15.3 to 8.8 ppm), and gestation (9.7 to 6.4 ppm) farms. Moreover, spraying the microbial agent at a 24 h interval significantly (p<0.01) decreased ammonia concentration from 19.9 to 10.4 ppm, from 11.1 to 4.1 ppm, and from 8.8 to 5.1 ppm in 5,000-, 3,000-, and 1,000-head farms, respectively. Overall, spraying microbial agents every day may be the most effective method to reduce odor in commercial pig farms.

This study was conducted to investigate the potential of toy provision for stress reduction, welfare improvement and toy preference in finishing pigs. Toy shape was expected to exert effects on stress related behaviors including fighting, bothering, and feed competition. Three different toy shapes (i.e. square, round, and oval) were given to groups of finishing pigs. A no toy control group was also included. The duration and frequency of abnormal behaviors and use time for toy preference were compared among groups. The duration and frequency of stress related behaviors was higher (p<0.01) among the non-toy-using finishing pigs on 20 minutes and 118 times than 16 minutes and 57 times of toy-using finishing pigs. Toy shape exerted no significant effects, however, toy use displayed a clear ability to reduce stress related behaviors among finishing pigs. Toy use time and shape both displayed no clear effect on the duration of stress related behaviors. These behaviors were most frequently displayed in the afternoons when the finishing pigs become most active, and were not affected by toy shape. Overall, the square shaped toy was used much longer (9.7 hours) and more frequently (566 times) in a 24 hour period by the finishing pigs (p<0.01). In conclusion, providing toys to finishing pigs reduces stress and stress related behaviors. This finding is expected to positively impact welfare and improve finishing pig productivity. Square shaped toys were most preferred by the finishing pigs, therefore adopting toys with square features is recommended.